Spirulina platensis, an important source of bioactive compounds, is a multicellular, filamentous cyanobacterium rich in high-quality proteins, vitamins, minerals, and antioxidants. Due to its nutrient composition, the alga is considered a complete food and is recognized for its anti-inflammatory, antioxidant, antiobesity, and reproprotective effects. All of which are important for prevention and treatment of organic and metabolic disorders such as obesity and erectile dysfunction. The aim of this study was to investigate the modulatory role of Spirulina platensis food supplementation and the mechanisms of action involved in reversing the damage caused by a hypercaloric diet on the erectile function of rats. The animals were divided into a standard diet group ; a hypercaloric diet group ; a hypercaloric diet group supplemented with S. platensis at doses of 25 , 50 , and 100 mg/kg ; and a hypercaloric diet group subsequently fed a standard diet . In the rats fed a hypercaloric diet, dietary supplementation with S. platensis effectively increased the number of erections while decreasing latency to initiate penile erection. Additionally, S. platensis increases NO bioavailability, reduces inflammation by reducing the release of contractile prostanoids, enhances the relaxation effect promoted by acetylcholine (ACh), restores contractile reactivity damage and cavernous relaxation, reduces reactive oxygen species (ROS), and increases cavernous total antioxidant capacity (TAC). Food supplementation with S. platensis thus restores erectile function in obese rats, reduces production of contractile prostanoids, reduces oxidative stress, and increases NO bioavailability. Food supplementation with S. platensis thus emerges as a promising new therapeutic alternative for the treatment of erectile dysfunction as induced by obesity. The close relationship between diet and health has been evidenced in many studies where the presence of bioactive molecules is described as influencing various metabolic pathways and systems within the organism. Abnormal eating habits represent a critical concern, promoting health disorders including cancer, diabetes, cardiovascular diseases, obesity, and sexual dysfunction , 2.Arthrospira platensis, better known as Spirulina platensis, is known for its medicinal and nutritional potential which is often attributed to its complex chemical composition. Its biological and pharmacological activities are already described [In recent decades, researchers have demonstrated a growing interest in natural sources of bioactive compounds such as fruits, vegetables, fish, herbs, and seaweeds as effective health promoters that can play an important and promising role in the prevention and treatment of disease –4. Seaweescribed –8.Spirulina platensis is a blue-green filamentous microalga, a multicellular photosynthetic cyanobacteria [β-carotene, fucoxanthins, phycobilins, and allophycocyanin [S. platensis, when used as a food supplement for humans and animals [bacteria –11, oftebacteria –14 and ccocyanin , 15, 16.cocyanin –19, anticocyanin , 21, immcocyanin , 23, antcocyanin , 25, antcocyanin , antimiccocyanin , and repcocyanin  properti animals , is bene animals –33.Erectile dysfunction is characterized as an inability to achieve and/or maintain adequate penile erection for satisfactory sexual intercourse . ED is aS. platensis promotes beneficial effects on the NO signaling pathway in the aorta of healthy rats [It has recently been shown that food supplementation with thy rats , reducesthy rats , and prethy rats , 42, higSpirulina platensis in reversing the damage caused by a hypercaloric diet (16 weeks) on the erectile function of rats and contributes to its development as a potential therapeutic agent for the treatment of obesity-induced erectile dysfunction.Given the above, our study is aimed at investigating the modulatory effects of food supplementation with 2·2H2O), magnesium sulfate heptahydrate (MgSO4·7H2O), and glucose (C6H12O6) were purchased from Vetec . Sodium bicarbonate (NaHCO3), sodium chloride (NaCl), and potassium chloride (KCl) were purchased from Nuclear . Monobasic potassium phosphate (KH2PO4), monobasic sodium phosphate (NaH2PO4), sodium hydroxide (NaOH), and hydrochloric acid (HCl) were purchased from Dinâmica .Calcium chloride dihydrate (CaClω-nitro-L-arginine methyl ester (L-NAME), indomethacin, tempol, apocinin, ethylenediamine tetraacetic acid (EDTA), MDA, and 1,1-diPHEnyl-2-picrylhydrazyl (DPPH) were purchased from Sigma-Aldrich (Brazil). To obtain the stock solutions, substances used in the functional experiments were dissolved and diluted in distilled water , being, respectively, kept at 4 or -20°C. The carbogen mixture (95% O2 and 5% CO2) was obtained from White Martins (Brazil). All substances were weighed on an analytical balance, GEHAKA model AG 200 .Phenylephrine (PHE) was purchased from Pfizer (USA). ACh, R-(-)-apomorphine, NRattus norvegicus), 2 months old and weighing approximately 150 g, were obtained from the Animal Production Unit (APU). The animals were maintained under controlled ventilation and temperature (21 ± 1°C) with water ad libitum in a 12 h light-dark cycle (lights on from 600 to 1800 h). The experimental procedures  were performed following guidelines for the ethical use of animals in applied etiology studies [Wistar male rats  (Lot No. 20130320). To certify the extract, a sample was then analyzed by the Pharma Nostra Quality Control Laboratory  (Lot No. 1308771A). Preparation of the powder was performed by Dilecta Manipulation Pharmacy  (Lot No. 20121025).S. platensis powder was dissolved in saline solution (NaCl 0.9%) at doses of 25, 50, and 100 mg/kg. The supplemented groups  received administrations for 8 weeks [The  8 weeks . Oral adS. platensis at doses of 25 (HCD+SP25), 50 (HCD+SP50), and 100 mg/kg (HCD+SP100); and rats fed a hypercaloric diet and later with the standard diet (HCD+SD); the SD group continued while receiving only saline as supplementation. All experimental groups were fed for a total of 16 weeks (In phase I of the study (8 weeks), the animals were randomly divided into two groups (5 rats/group): rats given a standard diet (SD) of Presence® containing 7% moisture, 3% ashes, 23% protein, 63% carbohydrate, 4% lipids, with an energy density/g of 3.8 kcal; and rats fed a hypercaloric diet (HCD) consisting of the standard diet (Presence®), supplemented with milk chocolate, peanuts, and sweet biscuits at a ratio of 3 : 2 : 2 : 1 , 41. The16 weeks , and aftThe animals were euthanized by guillotine and the corpus cavernosum removed, being immersed in nutrient solution at room temperature and bubbled with a carbogen mixture. The penis was isolated near its attachment to the ischium bone, and the penile dorsal vein and urethra were removed. The corpus cavernosum was then separated into two 1 cm segments (approximately). After separation, the organ was suspended vertically through two stainless steel metal rods in an isolated organ bath (6 mL) containing Krebs-Ringer solution at 37°C. The upper stem was connected to the isometric force transducer, with the resting tension equivalent to 0.5 g . The pre2 (2.5), MgSO4 (1.2), KH2PO4 (1.17), NaHCO3 (25.0), and D-glucose (5.6). The pH was adjusted to 7.4 [The Krebs-Ringer solution used presented a composition (in mM) of NaCl (118.4), KCl (4.7), CaCld to 7.4 .μg/kg) prepared in saline, and filmed for 30 min using two digital cameras.Each rat was placed in a glass box for 30 min , receiving a subcutaneous dorsal region injection of R-(-)-apomorphine  were obtained [Emax) and the negative logarithm (base 10) of the PHE concentration producing 50% of the Emax (pEC50). This, being calculated from the cumulative concentration-response curves, was obtained.As previously described, the corpus cavernosum was assembled, and after the stabilization period (60 min), cumulative concentration-response curves for PHE  [−5 M) [−8 − 3 × 10−3 M) were obtained.The corpus cavernosum was assembled as previously described. After stabilization, incubations (in distinct preparations) for a period of 30 min using a nonselective NOS inhibitor-L-NAME (10−4 M)  and a no) [−5 M)  were perEmax and pEC50 values obtained in the absence and presence of L-NAME and indomethacin in the separate preparations. The effects of the inhibitors on the cumulative concentration-response curve for PHE were compared between the SD, HCD, HCD+SP25, HCD+SP50, HCD+SP100, and HCD+SD treatments.The contractile response of the corpus cavernosum in the presence of the inhibitors was calculated based on the mean amplitude of the curve obtained from the SD group. Contractile reactivity was assessed based on PHE −5 M) was induced. Upon formation of the tonic component, ACh (10−11 − 3 × 10−4 M) was cumulatively added (in distinct preparations) to the organ bath [The corpus cavernosum was assembled as previously described, and after the stabilization period, a contraction with PHE , an NADPH oxidase inhibitor [−3 M), a superoxide dismutase (SOD) mimetic [−5 M), and upon formation of the tonic component, ACh (10−11 − 3 × 10−4 M) was added to the bath.After stabilization, either apocinin  was incubated in a water bath at 37°C for 60 min, and the samples were then precipitated with 400 μL of 35% perchloric acid and centrifuged at 26,295 g for 10 min at 4°C. The supernatant was transferred to new Eppendorf tubes, and 400 μL of 0.6% thiobarbituric acid was added. This was followed by incubation at 95-100°C for 30 min. After cooling, the samples were read at 532 nm. The concentrations of malondialdehyde in the tissue samples  were determined using an MDA standard curve constructed using a solution standard . The tissue absorbance values obtained were normalized to the dry weight present in each given sample volume.Lipid peroxidation was measured using the chromogenic product of 2-thiobarbituric acid (TBA) reaction with malondialdehyde (MDA); a product formed as a result of membrane lipid peroxidation . Tissue μL of the supernatant homogenate to appropriate centrifuge tubes, vortexed, and allowed to stand for 30 min. They were centrifuged at 1207 g for 15 min at 20°C, and the absorbance of the supernatant was read at 515 nm. The results were expressed as a percentage of oxidation inhibition where AOA (antioxidant activity) = 100 − ((DPPH · R) T/(DPPH · R) B 100), where (DPPH · R) and (DPPH · R) B correspond to the concentration of DPPH · remaining after 30 min, measured in the sample (T) and blank (B) prepared with distilled water. The tissue samples were homogenized with 10% KCl at a 1 : 1 ratio. The absorbance values obtained for the tissue were normalized to the dry weight present in a given sample volume.The procedure was based on the method described by Brand-Williams et al. , where 1n = 5) and statistically analyzed for intergroup comparison using Student's t-test. The results were statistically analyzed using two-way analysis of variance (ANOVA) followed by Bonferroni's posttest. The differences between the means were considered significant when p < 0.05. The pCE50 values were calculated using nonlinear regression [Emax was obtained by averaging the maximum percentages of contraction or relaxation. All results were analyzed using GraphPad Prism version 5.01 .The functional results obtained were expressed as mean and standard error of the mean (S.E.M.)  and 100 mg/kg (1.2 ± 0.2), no difference was observed as compared to the HCD group. However, the HCD+SP50 (1.8 ± 0.5) and HCD+SD (1.8 ± 0.2) groups presented an increase in the number of penile erections as compared to the hypercaloric diet group (0.3 ± 0.2) (In the HCD group (0.3 ± 0.2), it was observed that the number of penile erections was lower than that in the SD group (2.0 ± 0.4). When rats consumed the hypercaloric diet and were supplemented with 3 ± 0.2) .The latency to obtain penile erection in the HCD group (26.7 ± 2.2 min) was higher than that in the SD group (8.0 ± 1.0 min). In the HCD+SP25 (12.8 ± 2.6 min), HCD+SP50 (15.3 ± 3.3 min), and HCD+SP100 (13.4 ± 1.0 min) groups , as well as in the HCD+SD group (12.2 ± 3.5 min), a reduced latency time was observed as compared to the HCD group .Emax = 161.5 ± 11.2%; pEC50 = 5.6 ± 0.1), when compared to the SD group   .S. platensis at a dose of 25 mg/kg , the contractile reactivity of the corpus cavernosum was unaltered by PHE. However, supplementation at a dose of 50 mg/kg  increased the contractile efficacy of PHE when compared to the SD, HCD, and HCD+SP25 groups. However, in the S. platensis supplemented group (100 mg/kg), a reduction in the contractile efficacy of PHE  was observed as compared to that in the HCD group  (Emax = 166.4 ± 19.3%), the contractile efficacy of PHE was higher as compared to that in the SD group (Emax = 100%) or the HCD+SP25 group (Emax = 147.3 ± 13.4%)  . In the ± 13.4%) .Emax = 153.8 ± 17.9%; pEC50 = 5.5 ± 0.04) in the presence of L-NAME (a nonselective inhibitor of NOS) was observed as compared to the SD group in the absence of L-NAME . In the presence of indomethacin (a nonselective COX blocker) in the SD group, no change was observed in the PHE curve  as compared to its absence   .Emax = 80.0 ± 9.5%; pEC50 = 5.6 ± 0.2) as compared to the absence of L-NAME . A reduction in contractile efficacy for indomethacin in the absence of L-NAME  was also observed  and indomethacin  as compared to their absences  doubled in the presence of L-NAME. Similarly, the contractile efficacy of the agonist was also augmented in the presence of indomethacin  as compared to its absence   .Emax = 80.5 ± 14.4%; pEC50 = 5.9 ± 0.1). In the presence of indomethacin, contractile efficacy diminished by 3.8 fold  as compared to the absence of these inhibitors   .Emax = 53.5 ± 1.5%; pEC50 = 7.9 ± 0.1) as compared to that in the SD group . In the hypercaloric diet groups, supplementation with S. platensis at doses of 25  and 100 mg/kg  did not alter ACh-promoted relaxation as compared to that in the HCD group  (The relaxation efficacy of ACh was lower in the HCD group (2 ± 0.2) .S. platensis algae at 50 mg/kg (pEC50 = 7.1 ± 0.2) in the HCD+SD group (pEC50 = 7.0 ± 0.1) reduced ACh contractile potency as compared to that in the HCD group (pEC50 = 7.9 ± 0.1). The best relaxation efficacy for this agonist was observed in the HCD+SP50 group (Emax = 75.9 ± 2.7%), this as compared to that in the HCD group (Emax = 53.5 ± 1.5%). However, ACh relaxation was reduced in the HCD+SD group (Emax = 53.6 ± 2.8%) when compared to that in the SD group (Emax = 72.7 ± 3.3%) (Supplementation with  ± 3.3%) .Emax = 90.7 ± 6.9%; pEC50 = 8.1 ± 0.3) as compared to its absence . In the presence of apocinin, a NADPH oxidase complex inhibitor, no change in efficacy or relaxation potency  was observed when compared to its absence   .Emax = 84.4 ± 6.6%; pEC50 = 8.1 ± 0.4) without change in potency when compared to its absence . Additionally, there was no change in efficacy or relaxation potency in the presence of apocinin  as compared to the inhibitor absence curve   .S. platensis at 50 mg/kg did not alter the relaxation efficacy of ACh either in the presence of tempol (Emax = 78.4 ± 5.8%) or apocinin (Emax = 62.3 ± 1.8%) as compared to their absence (Emax = 53.5 ± 1.5%). However, the relaxation response was potentiated in the presence of both tempol and apocinin  as to its absence (pEC50 = 7.1 ± 0.2) (Supplementation with 1 ± 0.2) .μmol/L) presented a higher MDA concentration as compared to the SD group (0.5 ± 0.05 μmol/L). However, supplementation with S. platensis at doses of 25 (0.5 ± 0.1 μmol/L), 50 (0.3 ± 0.02 μmol/L), and 100 mg/kg (0.4 ± 0 02 μmol/L) reduced MDA levels in relation to both the HCD and SD groups. There was no difference in MDA concentration in the corpus cavernosum of the HCD+SD group (0.5 ± 0.1 μmol/L) as compared to either the HCD group or the SD group (The HCD group (0.9 ± 0.40 SD group .S. platensis at a dose of 50 mg/kg (91.0 ± 0.8%), there was an increase in the organ's total antioxidant activity as compared to the HCD group. A difference was also observed between HCD+SP50 and HCD+SP100   and those fed a hypercaloric diet (74.4 ± 4.6%). In rats fed a hypercaloric diet supplemented with  ± 3.5%) .Spirulina platensis through mechanisms involving NO, COX, and oxidative stress pathways.In the present study, we investigated evidence of erectile dysfunction development in Wistar rats as induced by consumption of a hypercaloric diet. It was shown that hypercaloric food intake resulted in reduced erectile function, increased contractile efficacy, and reduced corpus cavernosum relaxation, with increased release of contractile prostanoids and ROS synthesis. In contrast, the deleterious effects were restored by food supplementation with S. platensis at 25, 50, and 100 mg/kg. Additionally, in order to simulate a dietary reeducation process, another group of animals was fed a hypercaloric diet during the first 8 weeks being replaced by the standard diet during the following 8 weeks.Male Wistar rats were fed a hypercaloric diet for 16 weeks, the first 8 weeks being fed only with the standard diet or the hypercaloric diet , the following 8 weeks included alimentary supplementation with 2-like receptors present in nucleoparaventricular oxytocinergic neurons of the hypothalamus [In order to evaluate the rats' erectile function, R-(-)-apomorphine, an inducer of penile erection, was used. The substance presents high affinity for Dthalamus , 58.S. platensis supplementation, the animals demonstrated an increase in the number of penile erections (at the dose of 50 mg/kg), and a reduction in onset times to initiate penile erection . Moreover, the HCD+SD group presented an increase in the number of penile erections as well as a reduction in latency to initiate penile erection, demonstrating the expected improvement in erectile function. Although less effective than supplementation with S. platensis, such “lifestyle” changes, specifically towards healthy eating habits and physical activity contributing to the improvement of sexual function , and consequent reduction of NO availability in the corpus cavernosum, as well as with an imbalance between the production of contractile and relaxation prostanoids –68.Based on this information, L-NAME, a nonselective NOS inhibitor , and indEvaluating the rats consuming hypercaloric diet, a decrease in the contraction curve induced by PHE in the presence of the COX inhibitor when compared to its absence was observed , inferriS. platensis at a dose of 100 mg/kg promoted an increase in contraction in the presence of L-NAME, which may infer that S. platensis acts as a potent antioxidant, positively modulating NO pathways, increasing the substrate production and expression of NOS, as well as NO itself, consequently, removing the superoxide anion free radical that favors vasoconstriction. Thus, NO bioavailability would increase, augmenting its vasodilator effect making contractions more difficult [Dietary supplementation with ifficult , 41, 72.S. platensis at 50 and 100 mg/kg, an increase in the PHE curve was observed in the presence of indomethacin  would alter relaxation of the corpus cavernosum through ROS modulation.Excessive free radical production is triggered by increased body adiposity and contributes to vascular damage, causing reduced erectile function , 74. GivThe preparations were incubated with apocinin, a nonselective NADPH oxidase inhibitor, and tempol, a superoxide dismutase (SOD) mimetic, previously cited as inducing relaxation with ACh –77. In tSimilarly, when analyzing the hypercaloric diet rats, the ACh relaxation curve in the presence of apocinin and tempol was unchanged when compared to their absence. Thus, it is suggested that dietary change does not promote changes in the production of superoxide anion by NADPH oxidase, since in the absence of apocinin and tempol, both SD and HCD group relaxation curves overlap with their ACh relaxation curves. However, the possibility of ROS production involving alternative pathways in this complex cannot be ruled out.S. platensis at the 25, 50, and 100 mg/kg doses reduced oxidative stress markers and MDA levels in the corpus cavernosum, restoring the damage caused by the hypercaloric diet on the ROS pathway , on in vivo erectile function, contractile and relaxation reactivity, and oxidative stress in cavernous smooth muscle. In conclusion, chronic dietary supplementation (in vivo) with S. platensis promoted a greater number of erections and reduced latency times to erection as compared to the HCD group, altered cavernous smooth muscle reactivity, and resulted in decreased contractile responsiveness to PHE. ACh further increases this relaxation response and reduces oxidative stress in obese rats. The mechanisms underlying these effects include increased production of relaxation prostanoids, contractile reduction, increased NO bioavailability, reduced lipid peroxidation, reduced levels of ROS, and increased antioxidant activity in the corpus cavernosum (This study evaluated the effects and therapeutic potential of dietary supplementation with vernosum .


Heart rate (HR) oxygen uptake (VO2), rating of perceived exertion, weight, blood lactate (mmol·L−1), haemoglobin (g·dL), haematocrit (%) and glucose (mmol·L−1), and nutrition and hydration were recorded. SG ran for 17.5 h/day, covering ~120 km/day at ~7 km/h. Energy expenditure for each 24 h period was 6878 kcal/day and energy intake (EI) was 2701 kcal/day. EE was 382 kcal/h, with 66.6% from fat and 33.4% from carbohydrate oxidation. 7 day EI was 26,989 kcal and EE was 48,147 kcal, with a total energy deficit (ED) of 21,158 kcal. Average VO2 was 1.2 L·min−1/24.7 mL·kg·min−1, Respriatory echange ratio (RER) 0.80 ± 0.03, HR 120–125 b·min−1. Weight increased from 48.6 to 49.5 kg. Haemoglobin decreased from 13.7 to 11 g·dL and haematocrit decreased from 40% to 33%. SG ran 833.05 km. SG exhibits an enhanced fat metabolism through which she had a large daily ED. Her success can be attributed to a combination of physiological and psychological factors.Ultra-running comprises running events longer than a marathon (>42.2 km). The prolonged duration of ultra-running leads to decrements in most or all physiological parameters and considerable energy expenditure (EE) and energy deficits. SG, 47 years, 162.5 cm, 49 kg, VO Ultra-running events take place on a variety of terrains, ranging from treadmills to remote wilderness, and these variations not only affect the biomechanical, physiological, nutrition, and psychological [Ultra-running comprises running events longer than a marathon >42.2 km), with races contested over multiple distances  or time periods  in single-day and multi-day formats. The longest event held over km is 1000 km and for events held in miles, the longest distance is the “Self-Transcendence 3100 Mile Race” (4989 km) . Historically, our athlete displayed very low energy intake (EI) during running events that is not commensurate with energy expenditure (EE). Despite this, her performance has not been affected in past events of very long duration and intensity. In fact, she has often won, placed very highly, or set new records, often beating men. Therefore, it was our aim to monitor closely the EE and EI during seven days of continuous exercise to quantify the large energy deficit (ED) and any concomitant decrements in performance, as well as describing haematological or physiological parameters.SG is a female ultra-endurance runner with almost 40 years’ competitive experience. At the time of the event in 2011, she was 47 years old. She was not athletic as a teenager and did not start running until she was 22 years old. SG ran her first marathon in 1986 and has competed internationally for Great Britain at 100 km and 24 h, has completed more than 50,000 km of racing, running more than 400 marathons and over 150 ultra-endurance events. She holds multiple world records, the most recent being set in July 2019, where she broke the Land’s End to John O’Groats World Record  by over 4 h .This study was approved by Teesside University and the Waikato Institute of Technology (12/2011-TSWT201112URWRSG).The record consisted of running as far as possible (cumulative distance) on a treadmill over seven days. SG successfully completed a world record attempt, in accordance with Guinness World Record requirements. To be eligible for a record, efforts must be based upon one variable that is breakable, measurable, standardisable, and verifiable , with supporting evidence submitted as per Guinness World Records requirements .2), and overall rating of perceived exertion (RPE) were assessed. The athlete had a complete rest from 1–5 a.m. and slept in the same room that the treadmill was located in. The accompanying research crew consisted of members of University staff who rotated in shifts throughout the record attempt.The attempt took place during December 2011 in an open area of Teesside University, in the UK. SG chose the location due to access to three suitable treadmills , general facilities, and scientific testing equipment. Temperature was kept at a constant 20 °C throughout the attempt. SG ran in 3 h blocks followed by 30 min recovery periods to use the toilet, eat/drink, receive treatment , and to allow for data collection. During each 3 h block, heart rate (HR), breath by breath oxygen uptake , haemoglobin , and glucose . Samples for haematocrit were collected in heparinised glass tubes and spun for 5 min at 14,000 rpm (HaematoSpin 1400). Spun blood was analysed using a Hawksley micro haematocrit reader  to determine the percentage of red blood cells in the whole blood.Body mass was assessed before the start of the attempt and during every 30 min break . Body mass (kg) was expressed as a mean weight per day. Prior to analysis, all blood samples were taken from a fingertip capillary of the ring finger of the left hand. Baseline values were collected pre-attempt and immediately after each 3 h running block and analysed for blood lactate (mmol·L−1) intakes for macronutrients per day using specialist software . Relative intake (g·kg−1) and percent contribution towards the total of each macronutrient for each day was also calculated.Nutritional intake was recorded at time of consumption by the support crew in real time and food was weighed pre and post in cases of prepared meals. Intake was analysed for total energy  and absolute  and pasta with bolognese sauce, mincemeat and rice, and bean stew with rice. SG reported not being able to consume such large quantities in such a short space of time, as well as the food not being prepared in sufficient time for it to cool enough for her to consume it quickly. Therefore, from the middle of day 2 onwards, she only consumed one more cooked meal, instead relying upon cold foods, such as sandwiches, cereal, fruit smoothies, fruit, energy drinks, and chocolate , avoidin2 to calculate EE and as such, did not rely on HR data. The corresponding VO2 data show minimal fluctuations, so we can confidently extrapolate that HR was stable throughout the event. Gas exchange data was determined for 3 min at the end of each 3 h block using breath by breath online gas analysis , for the derivation of VO2, VCO2, and RER. The average of each 3 min sample was calculated from the raw, unfiltered breath by breath data. From measures of VCO2 and VO2, total carbohydrate (CHO) and fat oxidation rates were calculated using the formulas of Frayn [Heart rate (HR) was recorded every five seconds via telemetry . Due to an equipment/software failure, we only have data for one 24 h period (Day 3) for HR. We used VOof Frayn :Total fAlthough not possible to assess protein oxidation with our methods, we must assume some contribution of protein metabolism of approximately 5–15% towards energy production ,32, as aOverall rating of perceived exertion (RPE) was assessed via the CR-10 scale  and was Data are reported as means ± standard deviations, unless otherwise stated.SG successfully broke the record for seven consecutive days on a treadmill, covering 833.05 km in a total running time of 120 h 54 min 28 s, beating the previous female record holder by 182.73 km and previous male record holder by 79.33 km.2max test from October 2011, she reached a vVO2max of 16 km/h and achieved a VO2max of 48 mL·kg−1·min−1 (2.37 L·min−1). Lactate threshold occurred at 13 km·h−1, at a HR of 157 b·min−1, corresponding to approximately 80% VO2max.SG was 162.5 cm and 49 kg and in a VO−1, consisting of 441 ± 137 g CHO, 97 ± 33 g protein, and 64 ± 21 g fat. Of the total calories, 65% were from CHO, 14% from protein, and 21% from fat. SG consumed a total of 26.2 litres of fluid over the 7 days, averaging 3.6 ± 1 L·day−1. Sodium intake was 33,540 mg over the 7 days, averaging 4577 ± 967 mg·day−1.Energy and absolute and relative macronutrient intakes for each day of the seven-day attempt are presented in 2 sample during every 3 h block. The average VO2 for the 7 days was 1.2 ± 0.1 L·min−1 and 24.7 ± 3.4 mL·kg−1·min−1. Therefore, SG performed at ~50% of her VO2max for the entirety of the event. Respiratory exchange ratio (RER) averaged 0.8 ± 0.03 for the 7 days, with SG oxidising 33.4% CHO and 66.6% fat on average, respectively  and contribution towards EE from CHO and fats was derived from an unfiltered 3 min breath by breath VOectively .−1 with rest periods and sleep, or 382 kcal·h−1 for active periods only. Energy deficit  was calculated from continuous VO2 files and was 29,229 kcal over the 7 days, or 4174 ± 760 kcal·day−1.SG expended 48,147 kcal over the 7 days (including rest periods). This equates to an EE of ~286 kcal·h−1 on day 1. The lowest and highest readings were on day 2, with values of 2.65 mmol·L−1 and 9.14 mmol·L−1, respectively  to Hard (6). RPE reached 6 once on day 3 and twice on day 6. At the start of day 4, at 8 a.m., RPE was recorded as 2, which coincided with a period of walking.RPE remained mostly stable throughout the seven-day attempt B, with aSG finished the event 1 kg heavier than she started; 48.5 kg day 1 vs. 49.5 kg day 7 (increase of 2.06%). Mean body weight for the attempt was 48.5 ± 0.71 kg; however, there was a trend for bodyweight to increase over the course of the seven days, as shown in 2), fluid intake, blood lactate, haematocrit, haemoglobin, blood glucose, body mass, and overall rating of perceived exertion every 3 h over the 7 day world record attempt.We present data from a successful world record attempt set in the UK in 2011. SG broke the previous record of 753.24 km by 79 km for running continuously on a treadmill for 7 days and set a new world record of 833.05 km. We assessed EI  during the event suggests that she utilises fat and CHO efficiently, thereby reducing the energetic cost of exercise [Although the research on ultra-endurance performance is growing, many of the studies are lacking important data on participants; e.g., lactate threshold, VOformance . SG’s reexercise .The main finding from our investigation was that running for 7 consecutive days led to a significant daily ED which did not result in a commensurate weight loss. SG did not consume a lot of food during the 3 h running blocks, mainly eating during breaks. This led to a relatively high, but mainly stable blood glucose level for much of the event B. A studDuring multi day events, ultra-running athletes seldom consume sufficient energy to meet the estimated requirements based upon extrapolation of daily EE predictions for typical activities ,37. CompIt is difficult to accurately predict the energetic cost of ultra-distance events and therefore to establish optimal nutritional strategies that both complement the physiological demands of the activity and prevent loss of lean and fat mass is challenging . The EE −1, and athletes should expect to complete a race with EI of 36% to 54% of EE [−1 (17 to 37 g·CHO·h−1) of running, with an EE of 286 kcal·h−1 including rest periods and sleep, or 382 kcal·h− 1 for active periods only. SG expended 48,147 kcal over the 7 days and her total EI was only 18,918 kcal, resulting in a daily ED of 4175 ± 760 kcal·day−1 . Food and fluid intake during a 100 km off road race equated to a similar 176 Kcals per hour, but almost double the fluid intake at 415 mls per hour. However, temperatures were higher during this outdoor event [SG’s EI throughout the event typifies the EI of ultra-running athletes, where the recorded EI may be ≤50% of estimated EE ,13,19. F4% of EE . Insuffi4% of EE ,17. Per or event . Savouryor event , indicator event . We assuor event .Initially, SG planned to eat a pre-cooked meal every 3 h during her 30 min break, but she was unable to consume such large quantities in such brief rest periods. Therefore, from the middle of day 2 onward, she relied on CHO dense foods such as sandwiches, cereal, fruit smoothies, fruit, energy drinks, and chocolate, avoiding heavier high fat foods that SG attributed to past GI distress during ultra-running. Fuelling with a combination of carbohydrates in this manner may attenuate GI distress ,19. Gluc−1 of O2 consumed produced when oxidising 100% CHO compared with 4.7 kcal·L−1 of O2 from 100% fat [2max) could theoretically be attained by fat adapted athletes oxidising exclusively fat , SG pri100% fat . The mai100% fat . Fatigue100% fat ,48,49 an100% fat . Energetcal·h−1; ,52,53). Costa ,23 and JRunners are advised to drink approximately 400–800 mL per hour depending upon weight and intensity of running . Some ex−1 of fluid, which is a modest ~200 mL·h−1, compared with 500–700 mL·h−1 in reported cases of oedema [We did not assess body composition, but data from previous work ,57 suggef oedema . Increasf oedema , increasf oedema , increasf oedema , or impaf oedema . Milledgf oedema  found thIncreases or stability in BW in spite of large ED may also be due to plasma volume expansion, as estimated from changes in haematocrit and haemoglobin . AlteratPain may contribute to event termination in ultra-running , but paiThe management of sleep deprivation is also central in prolonged ultra-marathons . SG repoAs well as her ability to exercise very economically, SG’s success can also be attributed to very consistent pacing and well-structured breaks. An even pacing strategy seems crucial in ultra-running to preserve exercise capacity. For example, in 24-h ultra-marathoners, the fastest runners start at lower relative intensities and employ a more even pacing strategy than slower runners . Holt et2max, velocity at lactate threshold, maximal heart rate, and muscle strength [2max typically declines by ~10% per decade after the age of 25–30, this rate of decline is ~50% smaller in endurance athletes [2max and skeletal muscle characteristics, these will have been compensated for by higher oxidative enzyme activity, enhanced mitochondrial function [2 kinetics [A final consideration is that of age as age may reflect not just training status, but intra-muscular adaptations and tactical experience, especially in ultra-running, as participant age for best performance in ultra-marathon appears to increase with increasing distance and/or duration . Knechtlstrength . Althougathletes ,72. Sub-athletes . The facathletes . Howeverfunction ,73, and kinetics , thus pr2 measurements throughout the event.We did not assess body composition, either via sum of skinfolds or bioelectrical impedance, which would have allowed assessment of  changes in body composition. However, collection of these data would likely have furthered time constraints and disrupted the athlete as the data collection that took place was already quite time intensive. Due to equipment failure, we only have heart rate data for one 24 h period, thus not allowing us to describe the full HR profile for the 7 days. However, previous calculations of EE have only been estimated via HR, which may be transiently elevated by factors such as heat, anxiety, stimulant use, and dehydration. We are confident that our EE calculations are representative due to our consistent VORunning for 7 days on a treadmill and covering a world-record beating 833.05 km led to a substantial ED of 21,158 kcal, but surprisingly no weight loss and instead, a 1 kg weight gain. The weight gain was possibly the result of an increase in TBW, which was likely due to sodium retention, leading to a positive water balance; this is supported by the drop in Hb from 13.7 g/dL to 11 g/dL. The ED was due to the difficulty of consuming sufficient energy-dense foods without GI distress, which led the athlete to rely more heavily on liquid nutrition and smaller, more frequent meals of snack-type food. Despite this large ED, the EI and oxidation of CHO, fat, and lactate were adequate enough to maintain blood glucose for the majority of the event.Consistent pacing and regular breaks for fueling and recovery are necessary to sustain performance throughout long ultra-running events such as this. This case study demonstrates the difficulty of consuming sufficient calories during ultra-running, even with careful nutritional planning and with the event taking place in a seemingly optimal environment. Future studies of this kind should include bioelectrical impedance analyses to track changes in body water, muscle, and fat mass.


Docetaxel (DTX) is a widely used anti-tumour drug, and its dosage is solely determined by body surface area (BSA). Adverse events, such as neutropenia or unsatisfied efficacy, likely occur because of differences in the pharmacokinetics (PK) and pharmacodynamics of patients. Thus, a feasible dosage adjustment method is needed.A total of 209 eligible patients who provided consent were enrolled and randomised into two groups to receive the BSA- and PK-guided dosage adjustments of DTX-based chemotherapy (3 weeks per cycle). The AUC of DTX was detected, and the therapeutic window for Chinese patients was determined. The proportion of patients within the therapeutic window was evaluated. Neutropenia was examined in accordance with the toxicity grading standard suggested by the World Health Organisation. Tumour response was assessed in accordance with Response Evaluation Criteria in Solid Tumors version 1.1. The primary endpoint was the incidence of neutropenia, and the secondary endpoints were disease control rate (DCR) and 3-year survival rate.P < 0.0001), and the incidence of neutropenia was 68.33% versus 38.89% (P = 0.001) in the experimental group versus the control group in the sixth cycle, respectively. DCR was 72% versus 85% (P = 0.018) in the control group versus the experimental group. The 3-year survival rate of the PK group was significantly higher than that of the BSA group (P = 0.034).The therapeutic window for Chinese patients was 1.7–2.5 mg·h/L. The proportion of patients within the therapeutic window was 63.89% versus 28.33% (The PK-guided dosage adjustment of DTX could significantly increase the proportion of patients within the therapeutic window, decrease the incidence of neutropenia and increase the DCR and the 3-year survival rate. The PK-guided dosage adjustment based on the dynamic monitoring of AUC could be a useful method for oncologists to improve individualised treatment options, optimise drug efficacy and reduce drug toxicity. Docetaxel (DTX) is a paclitaxel-based antineoplastic drug that plays an antineoplastic role by interfering with the microtubule network necessary for cell mitosis and mitotic interphase . DTX canSimilar to the dosage of other chemotherapeutic reagents, DTX dosage is calculated solely on the basis of a patient’s body surface area (BSA). However, clinical data suggest that administering patients with the same dosage of DTX results in significant pharmacokinetic (PK) differences because of internal or external factors, such as genomic composition, physiological status, genetic characteristics and living habits . RemarkaNeutropenia is one of the main dose-limiting toxic effects of DTX. It can induce neutropenic fever, reduce dosage and result in early treatment discontinuation . The risThe area under a curve (AUC) of blood concentration is an important index for evaluating the absorption and PK of drugs in vivo. Neutropenia is closely correlated with the AUC of DTX amongst patients receiving DTX-based chemotherapy . Bruno eIn the present study, 209 patients who had solid tumours and received DTX-based chemotherapy were enrolled and randomised into a PK-directed DTX dosage adjustment group  and a BSA-based dosage group (BSA group or control group). An optimised therapeutic window for the Chinese population was explored and defined, and the proportion of patients within this therapeutic window was evaluated. The objective response rate (ORR), disease control rate (DCR), 3-year survival rate and neutropenia incidence were also evaluated.The Ethical Committee of Jiangsu Cancer Hospital approved the study, and all the patients signed an informed consent for the use of their personal data for research purposes. This study was conducted in accordance with the Declaration of Helsinki, Guidelines for Good Clinical Practice and the local laws and regulations of China.This work was a single-centre, prospective, randomised controlled study.9/L, platelet count ≥ 75 × 109/L and haemoglobin ≥ 90 g/L; serum total bilirubin of less than 1.5 times the upper limit of the normal value; aspartate aminotransferase and alanine aminotransferase of less than 2.5 times the upper limit of the normal value and serum creatinine of less than 1.5 times the upper limit of normal value; or creatinine clearance rate of more than 50 mL/min. The exclusion criteria were as follows: (1) received surgery or radiotherapy in the past 3 months; (2) abnormal liver, kidney, heart function and blood routine; and (3) patients with insufficient compliance in this experiment or receiving other treatments during the treatment course.The eligibility criteria of the study were as follows: (1) male or female aged over 18 years; (2) histologically confirmed solid tumours that could not be subjected to surgery or radiotherapy; (3) Eastern Cooperative Oncology Group score of 0–2, life expectancy of not less than 12 weeks; and (4) organ function level that met the following requirements: absolute neutrophil count ≥ 1.5 × 10n = 109, also referred to as the PK group) and the control group . All eligible patients received DTX-based chemotherapy 3 weeks per cycle. Chemotherapy did not exceed six cycles. In accordance with the patient’s physical condition, dosage was calculated on the basis of a BSA of less than 75 mg/m2. The drug was administered via an intravenous drip and completed within 1 h. From the second cycle, the PK group received dosage adjustment based on the PK parameter AUC of DTX. The BSA group continued to receive BSA-guided dosage. If the disease progressed or patients developed intolerable adverse reactions, treatment was discontinued, and patients received the best support of care.Patients who consented to the study were randomly divided into the experimental group . AUC was calculated on the basis of DTX dosage, start and end time of intravenous drip, blood sample collection time and DTX blood concentration by using the population PK model software provided by Saladax Company.Efficacy was evaluated every two chemotherapy cycles. Response was assessed in accordance with the Response Evaluation Criteria in Solid Tumors (RECIST 1.1). DTX-related neutrophils were classified in accordance with the toxic grading standard suggested by WHO.This study was designed to evaluate the effects of AUC-based dosage adjustment on clinical outcomes, such as the population rate within the therapeutic window and the incidence rate of neutropenia. The primary endpoint was the incidence rate of grades 3 and 4 neutropenia. The secondary endpoint was disease control rate (DCR). ORR was defined as the percentage of patients with a complete response (CR) or a partial response (PR). DCR was defined as the percentage of patients with a CR, a PR or a stable disease (SD).Data were analysed with SPSS 20.0, and measurements were expressed as mean . P < 0.05 indicated significant differences . The incidence rate of neutropenia between the two groups was compared via a Chi square test. DCR was compared via a Mantel–Haenszel test, and survival was examined with Kaplan–Meier analysis.n = 109) and BSA (n = 100) groups. Of the 209 randomised patients, 130 (62%) were male and 79 (38%) were female. The patients were 20–84 years old (57 ± 12). The baseline characteristics were similar between experimental and control groups and had no significant differences. All patients received treatment as allocated.Patients diagnosed with solid tumours and scheduled to receive DTX-based chemotherapy in our hospital from January 2015 to December 2016 were screened, and 209 patients were enrolled in this study. The patient baseline characteristics are summarised in Table In the 100 patients in the BSA group, the AUC of DTX was 0.5–5.3 (1.96 ± 0.81) mg h/L in the first cycle, 0.7–4.7 (1.90 ± 0.66) mg h/L in the second cycle, 0.7–3.6 (1.89 ± 0.58) mg h/L in the third cycle, 1.5–3.7 (2.35 ± 0.58) mg h/L in the fourth cycle, 1.3–4.6 (2.68 ± 0.72) mg h/L in the fifth cycle and 1.8–4.2 (2.85 ± 0.59) mg h/L in the sixth cycle. In the 109 patients in the PK group, the AUC of DTX was 0.5–5.1 (1.87 ± 0.87) mg h/L in the first cycle, 0.6–3.7 (1.81 ± 0.62) mg h/L in the second cycle, 1.1–3.6 (2.11 ± 0.5) mg h/L in the third cycle, 1.2–3.1 (2.12 ± 0.42) mg h/L in the fourth cycle, 1.2–3.1 (2.1 ± 0.43) mg h/L in the fifth cycle and 1.4–3.1 (2.28 ± 0.43) mg h/L in the sixth cycle.P = 0.9166), 41.00% versus 50.46% (P = 0.1705), 50.00% versus 61.90% (P = 0.0928), 48.24% versus 62.64% (P = 0.0546), 36.62% versus 71.08% (P < 0.0001) and 28.33% versus 63.89% (P < 0.0001) in the control group versus the experimental group from cycles one to six, respectively  mg h/L after BSA-based dosage was administered in the first cycle, which was as dispersed as in the control group, but being less dispersed after the cycles of dosage adjustment as indicated by the decreased standard derivation Fig. . The pro P = 0.098, 48.24%The AUC of paclitaxel amongst patients with lung cancer, breast cancer and gastric cancer under BSA- and PK-guided medication was further analysed. In lung cancer and breast cancer, the AUC of cycles 5 and 6 of the PK group was significantly lower than that of the BSA group, but the difference in the AUC of cycles 1–4 between the PK and BSA groups was not significant Fig. . In gastP = 0.814), 32.00% versus 32.11% (P = 0.986) and 41.30% versus 36.19% (P = 0.467) in the control group versus the experimental group in the first, second and third cycles of chemotherapy, respectively. No significant differences were observed. In the fourth, fifth and sixth chemotherapy cycles, the incidence rates were 49.41% versus 34.07% (P = 0.039), 56.34% versus 36.14% (P = 0.012) and 68.33% versus 38.89% (P = 0.001) in the control group versus the experimental group  and 72% versus 85% (P = 0.018) in the control group versus the experimental group, respectively. The efficacy of the PK group was significantly higher than that of the control group. The 3-year survival rate of the PK group was significantly higher than that of the BSA group , indicating that the PK-guided dosage adjustment of DTX significantly affected the improvement of the survival rate  mg h/L and less dispersed compared with that of the BSA group with a range of 1.8–4.2 (2.85 ± 0.59). The proportion of the patients in the therapeutic window increased after each cycle of adjustment. After six cycles of adjustment, their proportion reached 63.89% versus 28.33% (P < 0.0001) in the experimental group versus the control group. Thus, PK-guided dosage adjustment can effectively optimise DTX dosage. The incidence of neutropenia (grade 3 or above) in the experimental group was also significantly lower than that of the control group after three cycles of dosage adjustment. PK-guided dosage adjustment significantly increased the DCR and improved the survival rate of patients. Therefore, PK-guided dosage adjustment based on AUC detection could be a potential therapeutic option to optimise efficacy, reduce toxicity and improve the living quality of patients.The effects of PK-guided medication on patients with lung cancer, breast cancer and gastric cancer were investigated. At the late stage of chemotherapy for lung cancer and breast cancer, the AUC of PK-guided therapy was significantly lower than that of BSA-guided one. In the whole course of chemotherapy for gastric cancer, the difference in AUC between the PK- and BSA-guided drugs was not significant. Therefore, the PK guidance for DTX was in applicable to all malignant tumours. The value of PK-guided DTX for patients with lung cancer and breast cancer was higher than that for patients with gastric cancer.This study has several limitations. The proportion of the patients within the therapeutic window and the incidence of neutropenia significantly differed after several cycles of adjustment. However, the first two cycles were not significant, indicating that dosage adjustment should be further optimised. The PK-guided dosage adjustment based on AUC detection did not prolong the patients’ life in our study although their quality of life significantly improved. With limited data, the difference in the therapeutic window between Chinese, European and American populations could not be explained. Further studies are needed to answer these questions.The PK-guided dosage adjustment of DTX could significantly increase the proportion of patients within the therapeutic window, decrease the incidence of neutropenia and increase the DCR and the 3-year survival rate. The PK-guided dosage adjustment based on the dynamic monitoring of AUC could be a useful method for oncologists to improve individualised treatment options, optimise drug efficacy and reduce drug toxicity.


Chromolaena squalida, Campomanesia sessiliflora, Myrsine guianensis, Matayba guianensis, Siparuna guianensis, Ocotea minarum and Endlicheria paniculata—species from the Cerrado biome of Midwest Brazil—were extracted and evaluated for their antibacterial activity against a panel of four standard and three clinical multidrug−resistant bacterial strains. All tested oils showed moderate to good activity against at least four bacterial strains, including Salmonella Typhi and oxacillin−resistant Staphylococcus. The essential oils from C. squalida, C. sessiliflora, My. guianensis and Ma. guianensis showed strong inhibition of clinical Staphylococcus strains, which cause bovine mastitis and are related to milk−borne diseases. Their chemical profiles were investigated by gas chromatography coupled to mass spectrometry (GC/MS), which revealed a predominance of mono− and sesquiterpene hydrocarbons, some of which with well−known antimicrobial properties. The essential oil from Cerrado plants proved active against resistant Gram−positive and Gram−negative bacteria, revealing their potentialities for the development of new alternative agents to prevent the spreading of resistant bacterial contamination.Foodborne pathogens are a real public health concern in an escalating antimicrobial resistance scenario. Natural products represent a promising source of bioactive molecules, and essential oils have attracted much attention due to their myriad of biological properties, including antibacterial activities. In this context, essential oils obtained from the leaves of  Foodborne diseases comprise a large group of illness that result from the consumption of contaminated food or water. The diseases caused by foodborne microorganisms are considered a major concern in global public health, as they can cause significant losses in society and affect the economy, due to treatment, hospitalization and epidemiological investigation costs ,2,3. AccSeveral factors favor the increase in foodborne diseases, such as population growth, the need for large−scale food production and changes in eating habits . The situation is of great concern, mainly due to difficulties in controlling contamination of animals and animal origin products, as they involve multiple factors, such as water, fauna, soil, slaughter and processing practices and storage, among others .Staphylococcus, considered one of the main pathogens responsible for disease outbreaks related to the consumption of contaminated food [Staphylococcus types and production of enterotoxins [The most common foodborne disease worldwide is food poisoning caused by ted food . It can rotoxins . Some strotoxins ,8. In adrotoxins . These erotoxins  and is trotoxins .Staphylococcus aureus (MRSA). The emergence of multidrug−resistant pathogenic bacteria is a public health concern, as it restricts or extinguishes the availability of the existing antimicrobials [One of the main microorganisms responsible for bovine mastitis is methicillin−resistant crobials . Therefocrobials .6−C3 derivatives) [Plant natural products represent an important source of bioactive molecules, since these organisms produce a myriad of complex and structurally diverse chemical compounds, with great pharmacological potentials ,13. Essevatives) .In recent years, there has been a growing interest in the potential use of EOs in the food and cosmetics industries. Although EOs are often used in the industry as flavoring agents, these natural products possess a broad range of antimicrobial properties for food preservation. For instance, some EOs, alone or in combination with commercial antibiotics, have shown promising results against multi−resistant bacteria ,18. In aBrazilian flora, enclosed in biomes such as Pantanal and Cerrado, represents one of the highest potentials concerning biological diversity. The Cerrado biome, one of the largest Brazilian ecosystems, covers about 21% of the Brazilian territory and houses roughly 12,000 species of plants , ca. 30%In the face of our rich biodiversity and aiming at finding promising bioactive natural products for food preservation, the present work describes the evaluation of the antimicrobial potential of the essential oils from seven native plants of the Brazilian Cerrado against foodborne diseases−related bacterial stains. In addition, the chemical profile of four of these essential oils with the most promising activity is being described for the first time.The essential oils from the leaves of seven aromatic plants were obtained by hydrodistillation using a Clevenger−type apparatus, in yields of 0.01 to 0.2%, on a weight basis. The oils were tested against standard strains and clinical isolates of multi−resistant bacteria related to foodborne diseases , obtaineC. squalida, C. sessiliflora and My. guianensis showed good antimicrobial activity against the multi−resistant Staphylococcus sp. 841, isolated from cow’s milk with bovine mastitis, with emphasis on C. squalida, which showed the strongest activity (MIC of 7.80 µg·mL−1). The remaining oils were moderately active against this bacterium. All samples also proved moderately active against Staphylococcus sp. 873, as well as against the standard strains of P. aeruginosa and S. aureus, with MICs ranging from 500 to 125 µg·mL−1. Except for C. squalida and S. guianensis, all samples were moderately active against the standard E. coli strain. When evaluated against the β−lactamase producer E. coli and Salmonella Typhi 905 strains, the EOs of Ma. guianensis and C. sessiliflora also showed moderate activity, with an MIC of 500 µg·mL−1, while the remaining samples proved inactive against these bacteria.The EOs of C. squalida, C. sessiliflora, My. guianensis and Ma. guianensis, was analyzed by gas chromatography coupled to mass spectrometry (GC/MS)  . C. squalida and My. guianensis revealed the presence of 40 and 28 components, respectively, mostly of the sesquiterpene−type, and with a predominance of hydrocarbon sesquiterpenes . Among these compounds, viridiflorene (14.32%), germacrene D (12.74%), β−caryophyllene (12.54%) and δ−cadinene (11.60%) were the principal components of C. squalida, while isocaryophyllene (21.81%) followed by valencene (11.52%) and δ−cadinene (11.03%) were those of My. guianensis.The analysis of the EOs obtained from Ma. guianensis, which was shown to be composed almost exclusively of hydrocarbon sesquiterpenes (94.85%), such as bicyclogermacrene (31.32%), germacrene D (28.39%), β−caryophyllene (15.45%) and germacrene B (5.19%).Twenty−two compounds were identified in the essential oil from the leaves of C. sessiflora, on the other hand, showed similar contents of mono− and sesquiterpenes (roughly 42% of each class), in which α−pinene was the predominant monoterpene (38.65%), while β−caryophyllene (13.35%) and aromadendrene (12.52%) were the main sesquiterpene−type components.The EO of Chromolaena squalida, Campomanesia sessiliflora, Myrsine guianensis, Matayba guianensis, Siparuna guianensis, Ocotea minarum and Endlicheria paniculata were selected for the screening of antimicrobial activity based on the criteria of large distribution/occurrence in the Cerrado biome, as well as organoleptic characteristics, focusing on plants with leaves that, when crushed, give off a remarkable fragrance. The species selected in the present study are representatives of the families Asteraceae, Myrtaceae, Primulaceae, Sapindaceae, Siparunaceae and Lauraceae.S. aureus and E. coli, diarrheagenic E. coli, other Staphylococcus species, Clostridium botulinum, Salmonella enterica, Shigella spp, Campylobacter jejuni and Yersinia enterocolitica, among others [S. aureus, P. aeruginosa, E. coli and β−lactamase−producing E. coli were selected, in addition to two clinical isolated coagulase positive Staphylococcus spp. and Salmonella Typhi.Several bacteria are related to foodborne diseases, such as the commensal g others . In the C. squalida, C. sessilifora and My. guianensis showed the most potent antimicrobial activity against Staphylococcus sp. 841 resistant to ampicillin, doxycycline and clindamicyn, isolated from milk samples produced by cows affected by mastitis, with MIC values ranging from 7.80 to 31.25 µg·mL−1. Among these bioactive EOs, emphasis should be given to that from C. squalida, which strongly inhibited this bacterium with the lowest MIC, whose value is considered a good result even for pure substances [−1) against Staphylococcus sp. 873, also isolated from milk, however showing a larger resistance profile , as well as against the standard strain of S. aureus (MICs 125 to 500 µg·mL−1).The EOs of bstances . All tesStaphylococcus aureus is an important causative agent of bovine mastitis, which is one of the most cost−intensive diseases in the dairy industry [S. aureus strains have the potential to induce foodborne intoxications in humans transmitted by dairy products. A recent study evaluated over a thousand milk samples and revealed that S. aureus can effectively enter the dairy production chain via contaminated milk with subclinical S. aureus intramammary infections [industry . Furtherfections . Outbreafections ,29, reinC. squalida oil, with the best activity profile, are also present in the other EOs, however, in different proportions. The synergistic effect of these components in variable concentrations might therefore be overwhelming. Antimicrobial activity against Staphylococcus aureus and Candida guilliermondii was also reported for EOs rich in compounds similar to those found in C. squalida, such as EO from the leaves of Duguetia gardneriana (Annonaceae), with germacrene D (28.1%), viridiflorene (24.0%), β−pinene (12.6%), α−pinene (9.1%) and β−caryophyllene (5.6%) as its main constituents [C. squalida oil, proved active against Streptococcus mutans [Staphylococcus aureus [Helicobacter pylori [−1.It is notable that, regarding the chemical composition, the main components of the four EOs analyzed are mostly non oxygenated mono− and sesquiterpenes. In addition, the major components of tituents . β−Caryos mutans , Staphyls aureus  and Helir pylori . Pieri er pylori  evaluateP. aeruginosa and E. coli (standard strain) (MICs 500 µg·mL−1), except for C. squalida and S. guianensis, which proved inactive against the latter.Evaluated against Gram−negative bacteria, which tend to be more resistant to antimicrobial agents than Gram−positive bacteria because of the additional protection afforded by the outer membrane , all EOsMa. guianensis EO showed activity against β−lactamase−producing E. coli, with an MIC of 500 µg·mL−1. The composition of this EO is characterized by the presence of sesquiterpenes, with no trace of monoterpenoids, of which 31.32% consist of bicyclogermacrene. This main component was previously reported as active against P. aeruginosa, Acinetobacter baumanii and E. coli [It is worth mentioning that only  E. coli .C. sessiliflora was the only sample active against Salmonella Typhi 905, resistant to clindamicyn, penicillin and oxacillin, with an MIC of 500 µg·mL−1. A particular feature in the chemical profile of this EO was the presence of the monoterpene α−pinene as its major component . This monoterpene is listed by the US Food and Drug Administration among the food additives permitted for direct addition to food for human consumption, and also has been considered as a potentially useful natural antibacterial preservative as an alternative for SO2 in winemaking [The EO of nemaking .Chromolaena laevigata were investigated for their chemical composition and antimicrobial activity, showing an MIC of 62.5 mg·mL−1 against Candida albicans and S. aureus, and an MIC of 500 mg·mL−1 against P. aeruginosa [Campomanesia adamantium showed high activity against S. aureus, P. aeruginosa and C. albicans and was moderately active against E. coli, and its main compounds were found to be monoterpenes, such as limonene, α−pinene and β−pinene [Campomanesia guazumifolia (Cambess.) O. Berg strongly inhibited the strains of S. aureus (MIC 15 ± 0.1 µg·mL−1), E. coli (MIC 25 ± 0.2 µg·mL−1) and C. albicans (MIC 5 ± 0.1 µg·mL−1). Sixty−eight compounds were identified in its oil, of which the main constituents were bicyclogermacrene (15%), globulol (5%) and spathulenol (5%) [Although the antimicrobial effects and chemical composition of the plants evaluated in the present study have not been previously investigated, species belonging to the same genera as those investigated herein are known to exhibit antimicrobial properties. The EOs from flowers and fruits of ruginosa . The EO β−pinene . The EO nol (5%) .Chromolaena squalida, popularly known as cambará−roxa, mata−pasto, casadinha or erva−de−são−miguel [Campomanesia sessiliflora, popularly known as guabiroba−verde, is frequently found in the Brazilian Cerrado [Matayba guianensis, known as brazeiro, camboatá, camboatã, camboatá−branco, olho−de−cotia, mataíba, batabaíba, cuvantã, jatuá−uba, jatuá−iba, pau−da−digestão, atou−aou, tou−aou or canela−de−negro [Mysrine guianensis, popularly known as caapororoca, capororoca and pororoca [The use of leaves as a source of EOs warrants the sustainable use of these plants. This fact deserves to be highlighted, since such plants have popular/medicinal uses. The decoction of leaves of o−miguel , is usedo−miguel . The spe Cerrado  and prodde−negro , is consde−negro . The plapororoca , is usedpororoca  and antipororoca .Food safety can be considered as a priority, since foodborne diseases have emerged as a serious public health problem, besides leading to huge economic and social losses worldwide, especially in low− and middle−income countries. Our results reveal a promising activity of EOs from Cerrado plants against foodborne bacteria, revealing their potentialities for the development of new agents to prevent the spreading of resistant bacterial contamination in the food production chain, contributing to reduce the risks of foodborne diseases. Further toxicological studies are required for safety purposes.Plant Material. The leaves of the species Chromolaena squalida (DC.) R.M. King & H. Rob. (Asteraceae), Campomanesia sessiliflora (O. Berg) Mattos (Myrtaceae), Matayba guianensis Aubl. (Sapindaceae), Myrsine guianensis (Aubl.) Kuntze (Primulaceae), Siparuna guianensis A. DC. (Siparunaceae), Ocotea minarum (Nees & Mart.) Mez (Lauraceae) and Endlicheria paniculata (Spreng.) J.F. Macbr. (Lauraceae) were collected in March 2020, at Campo Grande, Mato Grosso do Sul, Brasil (20°30’29”S and 54°36’58”W). The botanical identification of the species was carried out by Dr. Flávio M. Alves (UFMS), and all exsiccates  were deposited at the CGMS Herbarium (UFMS). License for research on Brazil’s biodiversity, #A1D8864.Essential oil extraction. Fresh leaves of C. squalida (526 g), C. sessiliflora (486 g), Ma. guianensis (576 g), My. guianensis (483 g), S. guianensis (487 g), O. minarum (500 g) and E. paniculata (424 g) were separately subjected to hydrodistillation in a Clevenger−type apparatus for 8 h, to yield 280 mg (0.05% w/w), 916 mg (0.19% w/w), 1.2 g (0.2% w/w), 76 mg (0.015% w/w), 2.6 g (0.5% w/w), 690 mg (0.14% w/w) and 544 mg (0.13% w/w) of essential oils, respectively.Gas chromatography/mass spectrometry (GC/MS). The GC/MS analysis was performed using a Shimadzu GC/MS QP−2010 PLUS Gas Chromatograph coupled to a mass spectrometer operating at 70 eV and an Rtx−MS column  (30 m × 0.25 mm × 0.25 pm) consisting of 5%−diphenyl−95%−dimethylpolysiloxane.Chromatography conditions. Injector temperature was 250 °C, with the carrier gas (helium) at a flow rate of 1 mL·min−1, pressure of 87.1 kPa and column oven temperature programmed to 50–260 °C (3 °C/min). A mixture of linear hydrocarbons  was injected under the same experimental conditions. The identification of the constituents in the essential oil was performed by comparing the mass spectra obtained with those of the equipment database (Wiley 7 lib and Nist 08 lib) and by using the retention index (RI), calculated for each constituent as previously described [escribed .Antimicrobial assays. All reagents and media for the antibacterial assays were purchased from Sigma Aldrich™. The standard bacterial strains used were S. aureus (NEWP0023), E. coli (NEWP0022), E. coli  and P. aeruginosa (NEWP0027). Veterinary clinical strains Staphylococcus sp. 841, Staphylococcus sp. 873  and Salmonella Typhi 905  were provided by the Veterinary Hospital, Faculty of Veterinary Medicine and Animal Science of Universidade Federal de Mato Grosso do Sul . License of the bacterial collection for research on Brazil’s biodiversity, #C69392D.−1, with a 100 μL final volume in each well. The inoculums were overnight cultures of each bacterial species in Mueller–Hinton agar diluted in sterile saline solution (0.45%) to a concentration of approximately 108 CFU·mL−1. This solution was diluted 1/10 in saline solution (0.45%) and 5 μL was added to each well containing the test samples. All experiments were performed in triplicate and the microdilution trays were incubated at 36 °C for 18 h. Then, 20 μL of an aqueous solution (0.5%) of triphenyl tetrazolium chloride (TTC) was added to each well and the trays were again incubated at 36 °C for 2 h. In those wells where bacterial growth did occur, TTC changed from colorless to red. MIC was defined as the lowest concentration of each substance at which no color change occurred and was expressed in μg·mL−1.The antimicrobial activity of the essential oils was determined by the broth microdilution method, as described by Manda et al. (2018) . Two−fol


Based on phenotypic and phylogenetic analysis, this strain was identified as Pichia kudriavzevii GW1. The optimum conditions for NH3-N degradation by the GW1 strain were as follows: 0.3% inoculum concentration, 1.5 L/min aeration, pH 7, and a temperature of 35°C. Under optimized conditions, the GW1 strain degraded 95.5% of the NH3-N. The strain was then added to simulated black-odor water under optimal degradation conditions to investigate changes to the bacterial community over time. 16S rRNA sequencing of samples collected on days 0, 7, 14, and 21 showed that, in the presence of the GW1 strain, the relative abundances of the phyla Proteobacteria, Bacteroidetes, Chloroflexi, and Firmicutes increased in the black-odor water. In addition, the relative abundance of Propionivibrio, a known NH3-N degrading genus, increased. This study will facilitate the use of microbiological methods to repair black-odor water.In this study, a yeast strain with an outstanding NH With increased urbanization and industrialization, a large amount of domestic sewage and industrial wastewater are discharged into rivers, causing black-odor water in urban rivers and lakes. Currently, a total of 1861 water bodies (85.7% of rivers and 14.3% of lakes) in China are categorized as black-odor water , 3. BlacContaminants in water provide carbon sources and energy substrates, or intermediate metabolites, for microbial growth and reproduction to provide essential nutrients for microorganisms, which promotes the secretion of sufficient active enzymes for the degradation of pollutants , 13. The3-N) in black-odor water. In addition, we constructed a composite fungicide through the selected strains. We then identified the optimal conditions of composite microbial agents and examined their ability to treat black-odor water. The results of this work can provide an effective way to treat black-odor water.In the present study, our aim was to isolate microorganisms that possess a high degradation ability to treat black-odor water. To that end, we determined the morphology and characteristics of isolated bacterial strains and investigated their ability to improve the removal rates of COD and ammonia nitrogen , containing potassium dihydrogen phosphate (1 g/L), magnesium sulfate (0.5 g/L), peptone (5 g/L), glucose (10 g/L), agar (19 g/L), Bengal red (0.033 g/L), chloramphenicol (0.1 g/L), and distilled water (1000 mL). Bacteria were grown in beef extract peptone medium containing beef extract (3 g/L), peptone (10 g/L), sodium chloride (5 g/L), starch (1 g/L), agar (15 g/L), and distilled water (1000 mL). Actinomycetes were grown in Gao's No.1 medium (pH 7.4–7.6) containing soluble starch (20 g/L), potassium dihydrogen phosphate (0.5 g/L), sodium chloride (0.5 g/L), magnesium sulfate (0.2 g), potassium nitrate (1 g/L), ferrous sulfate (0.01 g/L), agar (15 g/L), 3% potassium dichromate (3.3 mL), and distilled water (1000 mL).Triplicate river sediment samples (10 g each) were added to sterilized 150 mL conical flasks containing 100 mL beef extract peptone medium, Gao's No. 1 medium, or Martin's liquid medium. Flasks were placed in a shaker and incubated for 2 days at a constant temperature (28°C). After the culture medium became turbid, 10 mL of the enrichment was aliquoted into an Erlenmeyer flask, supplemented with 100 mL of fresh medium, returned to the shaker, and incubated for 2 days at constant temperature (28°C). This process was repeated 2-3 times. Using this method, bacteria, fungi, and actinomycetes in the river sediment were separately enriched.μL of different concentrations  of bacteria, fungi, and actinomycetes suspension was taken and inoculated into the prepared medium . After culturing for 2 days in a constant temperature incubator at 30°C, dominant colonies with different characteristics were picked and grown on the selection medium. After inoculating the bacteria, the selected medium was placed in a constant temperature incubator at 30°C for 2 days. Microorganisms capable of degrading NH3-N in black odorous sewage were initially screened.About 100 3-N was measured using the Nessler colorimetry method [3-N degradation rate of each strain was determined and strains with higher degradation rates were selected for identification.Isolated strains were cultured in screening medium . A negative control was performed by incubating screening medium without inoculum. NHy method . The NH3http://www.ncbi.nlm.nih.gov). All similar sequences were retrieved from NCBI and a phylogenetic tree was constructed using DNAStar.The GW1 strain was subjected to Gram staining, morphological analysis, and 18S rDNA sequencing. Genomic DNA was isolated using the Ezup Column Bacteria Genomic DNA Purification Kit . The standard 18S rDNA gene PCR primers (ITS1: TCCGTAGGTGAACCTGCGG and ITS4: TCCTCCGCTTATTGATATGC) were used to amplify the target gene sequence of the GW1 strain. The PCR cycles were as follows: 2 min at 98°C; followed by 25 cycles of 98°C (10 s), 55°C (15 s), and 72°C (15 s); and a final extension at 72°C for 5 min. The resulting PCR products were then sequenced by Tsingke . Sequences similar to the GW1 strain were identified using BLAST  was used to increase the dissolved oxygen content of the different treatments. Five black-odor water aeration levels ) were tested. In order to evaluate the effect of pH on the degradation of NH3-N by fungi, hydrochloric acid (0.1%) and sodium hydroxide (0.1%) were used to adjust the initial pH of the water to 5, 6, 7, 8, and 9. The pH of the raw water was 6.4. The black-odor water environment without pH adjustment was used as a control group. The temperature most suitable for the degradation of NH3-N was determined by incubating treatments at 20°C, 25°C, 30°C, 35°C, and 40°C. For all of the treatments, each group was evaluated in triplicate and the water quality index was measured every 2 days. The degradation rate of black odorous NH3-N was detected along with the water quality index. The national standard method was used to detect NH3-N and COD in the black-odor water samples. The COD of the water samples was detected using the dichromate method. The NH3-N in the sewage sample was detected by Nessler spectrophotometry.The natural black-odor water environment was simulated by adding approximately 5 cm of the river bottom mud into an 8 L glass cylinder containing approximately 4 L of black-odor sewage. The cylinder was placed at room temperature (25°C), with light and other factors remaining consistent. The effects of concentration, aeration, pH, and temperature were evaluated to determine the optimal conditions for NH3-N degradation conditions. The concentration, aeration, pH, and temperature were set at 0.1%, 0.2%, and 0.3%; 0.5 L/min, 1 L/min, and 1.5 L/min, 6.5, 7, and 7.5; and 30°C, 35°C, and 40°C, respectively.The best three levels for orthogonal experiments are based on single-factor experiments. An orthogonal design containing four factors and three levels was adopted to further optimize the NHμL of elution buffer and stored at −80°C until being sent to LC-Bio Technology Co., Ltd  for PCR amplification. The degradation rate of black odorous sewage NH3-N and the water quality index were measured.A black-odor sewage degradation test was carried out under the optimal degradation conditions. DNA was extracted after the addition of the GW1 strain on days 0, 7, 14, and 21  using the E.Z.N.A. Stool DNA Kit  according to the manufacturer's instructions. Nuclease-free water was used as a negative extraction control. Total DNA was eluted with 50 The data was analyzed using SPSS 20.0 statistical software.3-N degrading abilities from the black-odor sewage. 3-N (1 g/L) degradation rates ranged from 30.5% to 93.2% , but the degradation rate of NH4 decreased with the increase in aeration rate. When the pH was 7, the degradation rate of NH3-N reached 92.54%. The degradation rate of NH3-N decreased when the pH was increased or decreased. 3-N degradation rate. At 35°C, the NH3-N degradation rate reached the highest value (88%). When the GW1 strain was treated with black-odor water, the factors affecting both the NH3-N and COD removal rates were as follows: A > D> B > C (Tables A3B3C3D2, specifically the concentration is 0.3%, the aeration is 1.5 L/min, the pH is 7, and the temperature is 35°C. Since the optimal combination was not in the 9-group test, a confirmatory test was performed under these conditions. The removal rate was 95.5%, which was greater than the maximum removal rate in the orthogonal test, indicating that the method is reproducible.The effects of concentration, aeration, pH, and temperature on the degradation of NHthe best .  FigureD > B > A > C, namely, temperature > aeration > concentration > pH. Therefore, the best process is A2B3C2D2, specifically the concentration is 0.2%, the aeration rate is 1.5 L/min, the pH is 7, and the temperature is 35°C. Since the optimal combination was not in the 9-group test, a confirmatory test was performed under these conditions and the GW1 strain was measured. The COD removal rate was 92.7%, which was greater than the maximum removal rate in the orthogonal test, indicating that the method has good repeatability.For the factors affecting the COD removal rate, the primary and secondary order is The relative abundance of bacteria at the phylum level of the four samples is shown in At the class level, the bacterial community was dominated by Betaproteobacteria, Deltaproteobacteria, Gammaproteobacteria, and Bacteroidia . BetaproPropionivibrio was significantly higher than that of the CON sample (Pseudomonas, Tolumonas, and Aeromonas increased compared to the other samples. In contrast, the abundances of Longilinea, Bellitina, Dechloromonas, Clostridium, Spirochaeta, Syntrophus, Desulfobulbus, and Smithella were lower compared to the other samples. Changes in these microbial abundances may be an important factor in the degradation of NH3-N.The heatmap shows the 20 most dominant genera in the bacterial community of the four samples . The resN sample . In the 3-N degrading bacteria from the river sediment of black-odor water. From these, we selected the GW1 strain, which had the highest degradation rate, for subsequent experiments. Morphological, DNA sequencing and phylogenetic tree analysis confirmed that the strain was P. kudriavzevii. P. kudriavzevii is commonly used in food processing [3-N degradation ability of P. kudriavzevii has not been previously reported. In this study, we identified a strain of P. kudriavzevii with the ability to degrade NH3-N. Single-factor and orthogonal experiments showed that the optimal conditions to improve the black-odor water were a P. kudriavzevii strain concentration of 0.3%, gas volume of 1.0 L/min, and a pH of 7.5. The optimal degradation conditions were then tested in a simulated environment. Although there will be some discrepancies with the natural environment, this study provides new insights into the application of this compound microbial agent for the bioremediation of black-odor water. Specifically, the isolated bacteria have the ability to degrade NH3-N from the sediment of black and odorous sewage river water, which lays a foundation for bioremediation in these areas.In this study, we screened NHocessing . To the Pichia kudriavzevii GW1, which will be included in our subsequent experiments. In situ bioremediation with indigenous microorganisms is an effective method to eliminate pollutants [3-N in black-odor water. At the genera level, Betaproteobacteria and Deltaproteobacteria were less abundant in the control compared to the other samples. Previous studies have reported that Betaproteobacteria and Deltaproteobacteria play a crucial role in removing nitrate and nitrite [3-N in the black-odor water. The heatmap also showed that after the compound microbial agent was added, the bacterial diversity increased with time, thereby suggesting that the compound microbial agent may affect the diversity of the bacteria. Compared with the control group, the richness of Propionivibrio, Geobacter, Pseudaeromonas, Aeromonas, and Tolumonas increased significantly after 7, 14, and 21 days. A recent study showed that, at low temperatures, Propionivibrio was a key member of the bacterial community that simultaneously removed nitrogen and phosphorus [Propionivibrio plays an important role in the degradation of black-odor water; however, this hypothesis needs further verification.Microorganisms can affect colonies in the environment by secreting some extracellular and intracellular enzymes . In addillutants . Becausellutants –28. Thesllutants , 30. Thellutants . The sclllutants . The inc nitrite –35, whicosphorus . Therefo3-N has been successfully isolated from river sediments of black-odor water. This strain was identified as Pichia kudriavzevii GW1 based on phylogenetic analysis and phenotypic characteristics. This is the first report of a Pichia strain possessing the ability to degrade NH3-N. The optimal conditions under which strain GW1 improves black-odor water were determined. This work may be used to help develop a cost-effective and environmentally friendly method for bioremediation of black-odor water.In summary, a strain with the ability to degrade NH


Chaetoceros muelleri, a marine diatom. The optimization process was conducted using response surface methodology (RSM) with two independent parameters, i.e., the initial concentration of antibiotics and contact time. The optimum removal of SMX and OFX were 39.8% (0.19 mg L−1) and 42.5% (0.21 mg L−1) at the initial concentration (0.5 mg L−1) and contact time (6.3 days). Apart from that, the toxicity effect of antibiotics on the diatom was monitored in different SMX and OFX concentrations (0 to 50 mg L−1). The protein (mg L−1) and carotenoid (μg L−1) content increased when the antibiotic concentration increased up to 20 mg L−1, while cell viability was not significantly affected up to 20 mg L−1 of antibiotic concentration. Protein content, carotenoid, and cell viability decreased during high antibiotic concentrations (more than 20 to 30 mg L−1). This study revealed that the use of Chaetoceros muelleri is an appealing solution to remove certain antibiotics from wastewater.Antibiotics are frequently applied to treat bacterial infections in humans and animals. However, most consumed antibiotics are excreted into wastewater as metabolites or in their original form. Therefore, removal of antibiotics from aquatic environments is of high research interest. In this study, we investigated the removal of sulfamethoxazole (SMX) and ofloxacin (OFX) with  Efficient wastewater treatment is vital for both industries and municipalities. There are several kinds of pollutants in wastewater, including pharmaceuticals . SeveralIncreasing antibiotic consumption results in rising environmental pollution  since anTherefore, eliminating these antibiotics with conventional wastewater treatment processes are limited. Furthermore, removing antibiotics generally involves high cost . Thus, f2. Furthermore, microalgae are considered to have high growth rates, high photosynthetic effectiveness, wide adaptability, and good potential to eliminate contaminants from wastewater [2 fixation [Chaetoceros muelleri (Chaetoceros muelleri); (2) to optimize the surface methodology (RSM) response; and to measure (3) toxicity effects of antibiotic concentrations on Chaetoceros muelleri.Using microalgae as an environmentally friendly and low-cost water treatment technique has been considered as a way to eliminate pollutants from water bodies . Amenorfstewater . One of fixation . Chaetocmuelleri  has been−1, each antibiotic was dissolved in distilled water. Such stock solutions were then diluted to obtain antibiotic concentrations. Chaetoceros muelleri was obtained from the photobioreactor in our laboratory, which operated at room temperature (25 °C) with light:dark cycles of 12:12 h (light was set around 60 to 70 μmol photons m−2 s−1) [Based on the study by Mojiri et al. , synthetperature  °C with perature 5 °C with−2 s−1 in the F/2 medium and artificial seawater, Chaetoceros muelleri was cultivated. The F/2 medium was included several compounds such as NaNO3, NaH2PO4, Na2H2EDTA, FeCl3·6H2O, MnCl2·4H2O, ZnSO4, Na2SiO3 etc., as described by [6 cell mL−1) of marine diatom [−2 s−1) . The phz et al.  and Sun z et al. , respect−1. The 3σ/s was [High performance liquid chromatography  was furnished with a UV detector. The detection wavelength was set at and 288 nm to monitor the concentrations of antibiotics, as described by Oh et al.  and Guo 3σ/s was  consideriC and fC indicate the initial concentrations of antibiotics, and concentration of antibiotics in effluent after treatment, respectively.The removal efficacy of antibiotics was evaluated based on Equation (1). Two factors, including antibiotic concentrations and contact time, were considered as independent parameters.−1 to 3 mg L−1 [Y defines antibiotic removal, the constant coefficient is presented by 0β, k displays the number of factors, and jX and iX demonstrate the variables. Moreover, the interaction coefficients of the linear, quadratic, and second-order terms are presented by j, βjj,β and ijβ, respectively.The total concentrations of antibiotics ranged from 0.5 mg L3 mg L−1 . Contact3 mg L−1 . Design −1) were conducted in batch experiments from 0 to 8 days, as described by Chen et al. [−1) suspension under constant light of 66 μmol photons m−2 s−1. Total protein (mg L−1), carotenoid concentration (μg L−1), and cytotoxicity (%) were monitored in the triplicate as follows. Protein content was analyzed with the UV-Vis spectrophotometer at 595 nm, as described by Chia et al. [Assessing the ecotoxicological effects of antibiotics at different antibiotic concentrations  at a wavelength of 470, 630, and 664 nm are defined by 470A, 630,A and 664A, where chlorophyll a and b are defined by aC and bC, respectively.Total carotenoid concentration was monitored by a spectrophotometer  at 470 nm, as described by Costache et al.  and baseCytotoxicity (%) was assessed as described by Namasivayam et al. . The optChaetoceros muelleri. The elimination effectiveness was optimized by RSM, as shown in Two steps were considered during the current study. In the first step, the SMX and OFX were removed by −1) was reached at contact time (5.0 days) and initial concentration of antibiotics (0.5 mg L−1). In addition, the minimum abatement of SMX (18.3% or 0.54 mg L−1) was reached at a contact time (0.5 days) and initial concentration of antibiotics (3.0 mg L−1). Bai and Acharya [As shown in  Acharya  reported−1) was obtained at a contact time (6.5 days) and initial antibiotic concentration (0.5 mg L−1). Moreover, the minimum OFX reduction (21.7% or 0.65 mg L−1) was obtained at a contact time (0.5 days) and initial antibiotic concentration (3.0 mg L−1). Further, Ref. [−1).Apart from that, the maximum reduction of OFX  is an environmentally friendly method that does not produce secondary pollutants . Hena et−1) and 42.5% (0.21 mg L−1) at the initial concentration (0.5 mg L−1) and initial contact time (6.3 days). 2R . R2  displayeChaetoceros muelleri were investigated. Some PPCPs can have a toxic effect on microalgae species during the removal of pharmaceuticals and personal care products (PPCPs) with algae-based systems . In thisChanges in protein content and carotenoid concentration are important indicators to monitor the toxicity effects of pharmaceuticals micropollutants on algae ,52.−1 of antibiotics were added and samples were taken after 1, 2, 3, 4, 5, 6, 7, and 8 days, respectively. Details about toxicity experiments are summarized in −1) was recorded at runs 44 and 45 . Moreover, the minimum protein content was 1.9 mg L−1 at run 48 . There was no huge difference between the maximum and minimum recorded protein contents. Liu et al. [Navicula incerta) decreased from 17.7% to 46.7% when pharmaceutical concentrations increased. Apart from that, Yang et al. [As shown in u et al.  stated tg et al. . This in−1) was reached at run 38 . This means that the total carotenoid concentration increased when the amount of antibiotic increased to 10 mg L−1. Moreover, the minimum total carotenoid concentration (2.2 μg L−1) was reached at run 48 . Then, the total carotenoid decreased when antibiotic concentration increased 10 mg L−1 to 50 mg L−1. Zhang et al. [a. Wang et al. [a in Microcystis increased at low pharmaceutical concentrations but was reduced at high pharmaceutical concentrations. Guo et al. [−1 cell−1) in control to 1.67 units after four days. Singh et al. [The maximum total carotenoid concentration  of antibiotics from 10 to 20 did not have any significant effects on cell viability (cytotoxicity). Xiong et al. [−1 of ofloxacin compounds could significantly inhibit microalgae growth and activity. Viability of C. reinhardtii decreased around 68% after 72 h of exposure to antibiotics, compared with the control (blank) [Increasing the concentration  . Apart fChaetoceros muelleri in eliminating sulfamethoxazole (SMX) and ofloxacin (OFX). The key achievements of the study are as follows:−1) and contact time (6.3 days), the optimum removal of SMX and OFX were 39.8% (0.19 mg L−1) and 42.5% (0.21 mg L−1).Based on the RSM at the initial concentration (0.5 mg LR2 value and rational distribution of experimental data compared to the predicted data.The RSM optimized the removal of antibiotics with diatoms in a logical way because of the high Based on the toxicological effects of antibiotics on microalgae, total carotenoid concentration, protein and cell viability decreased at high antibiotic concentrations.Conventional treatment techniques for domestic sewage treatment plants do not efficiently eliminate antibiotics. Thus, we investigated the potential of