The results showed that the Ni nanoparticles were uniformly loaded on the surface and hollow porous structure of the Ni/C porous fibers. Meanwhile, the content and size of the Ni nanoparticles on the Ni/C porous fibers can be controlled. Due to a suitable filling content, the synergistic effect of dielectric loss, interface polarization loss, magnetic loss and porous structure of the Ni/C porous fibers, an excellent microwave absorption performance was achieved. The minimum reflection loss value reached −43.0 dB, and a reflection loss value less than −10 dB was in the frequency range of 11.2–16.1 GHz with 2.0 mm thickness. In particular, under matching thickness (1.5–3.5 mm), the values of all the reflection loss peaks were below −20.0 dB. It is believed that this work can not only provide a new way to design excellent carbon-based microwave absorbing materials, but also offer an effective design strategy to synthesize biomass nanocomposites.Composites obtained by incorporating magnetic nanoparticles into porous carbon materials are promising in serving as microwave absorbing materials. In this study, Ni/C porous fibers were successfully synthesized through a simple  Ni/C porous fibers derived from jute fibers exhibited excellent microwave absorption performance. For example, Chen et al. prepared NiFe2O4 hollow nanoparticles/graphene composite by a three-step synthesis method.10 Compared with NiFe2O4 nanoparticles and the mixture of NiFe2O4 nanoparticles and graphene, the NiFe2O4 hollow nanoparticles/graphene composite showed better microwave absorption performance. The minimum reflection loss (RL) was −40.9 dB and the RL value less than −10 dB was in the frequency range of 13.5–18 GHz. Ji et al. prepared FeCo/porous carbon fiber composite through electrospinning and subsequent heat treatment, and a minimum RL value of −56 dB was achieved.11 The excellent microwave absorption performance was mainly attributed to the strong dielectric loss and magnetic loss as well as the porous structure of the material. Although some progress has been made in the exploration of carbon-based composite MAMs, the carbon matrix materials used were mainly carbon fibers, carbon nanotubes, graphene and metal–organic framework compounds.10–15 The preparation method with cheap raw materials, simple process, and adjustable magnetic content in a wide range is still a challenging topic and difficulty in the research field of carbon-based MAMs.In recent years, carbon materials have been widely studied by researchers due to their good chemical and thermal stability, excellent dielectric properties, and low density. The optimized combination of magnetic nanoparticles and carbon materials can not only overcome the defects of high density of magnetic nanoparticles such as ferrite, magnetic metal, magnetic metal oxide, and alloy, but also improve the electromagnetic matching and synergistic effect, and achieve excellent microwave absorption performance.16,17 Recent studies showed that the porous structure was conducive to enhancing electromagnetic wave absorption, which was mainly attributed to the reflection and multiple scattering of electromagnetic wave in the porous media.18,19 The porous structure can not only reduce the density of the material, but also enhance the microwave absorption performance. Therefore, the research on biomass porous carbon materials would be a developing trend of new carbon-based MAMs.3,20 Natural cellulose is the one of the main biomass resources, which has good hygroscopicity and uniformity. Moreover, the cellulose contains a lot of –OH, which can provide many active sites for the loading of nanoparticles. Nowadays, the preparation of porous carbon materials using cellulose as precursor has aroused the attention of scholars in material fields, and the cellulose used to prepare carbon-based absorbents was mainly related to cotton.21–23 For example, Gong et al. prepared magnetic porous carbon using nickel nitrate and waste cotton as precursors.21 Due to the sufficient dielectric loss and a proper electromagnetic match, when the filler loading is only 10 wt% and the thickness of the absorber is only 1.9 mm, the minimum reflection loss could reach −40.5 dB at 15.8 GHz. Jute fiber, the second largest natural cellulose fiber, is low cost and ecological friendly. Jute fiber is long and thin with a diameter of 10–40 μm, and it has cell cavity. Therefore, jute fiber can be used as an economic and feasible raw material for preparing hollow porous carbon fiber and combining magnetic nanoparticles, which is expected to show excellent microwave absorption performance. However, there is no report in the current literature.Biomass is a kind of abundant renewable resource. In recent years, the efficient utilization of biomass has become a hot and difficult issue. After carbonizing biomass, porous carbon materials with multi-stage pore size distribution can be obtained.in situ template method to prepare Ni/C porous fibers by using low-cost jute fiber as carbon source and template. By controlling the concentration of nickel nitrate, the precise and uniform loading of Ni nanoparticles on porous carbon materials can be realized, and the content and size can be further regulated in a wide range. As we expected, the Ni/C porous fibers showed excellent microwave absorption performance. This method has the advantages of low cost, abundant resources, simple technology, good repeatability, and suitable for large-scale preparation, which provides a new way to design excellent carbon-based MAMs.In this research, we report a simple 2.2.13)2·6H2O was A.R. grade. The commercially available jute fiber was applied as raw material. Deionized water was used throughout the study. N2  was used as a protective gas.In this work, Ni2 aqueous solution with the concentration of 0.2 mol L−1, 0.5 mol L−1 and 1.0 mol L−1, respectively. After soaking for 24 h, the wet jute fiber was removed with tweezers. When there was no solution dripped down, it was put into the evaporating dish and dried at 60 °C for 15 h. The product obtained above was then put in a ceramic boat and annealed in a horizontal tubular furnace at 700 °C, with a heating rate of 4 °C min−1 in N2 atmosphere. After holding for 2 h, the sample was naturally cooled to room temperature and removed. The samples obtained were Ni/C porous fibers, which were named as Ni/C-0.2, Ni/C-0.5, and Ni/C-1.0, respectively. As a contrast, the jute fiber was also annealed under the same conditions. The obtained sample was porous carbon fiber, which was named as PCF.Ni/C porous fibers were synthesized by a simple 2.2θ range of 10° to 90°. Field-emission scanning electron microscopy  with electron energy dispersion spectroscopy (EDS) and transmission electron microscope  were used to characterize the morphology and structure of the samples. The thermogravimetric analysis was carried out on a STA6000 simultaneous thermal analyzer from room temperature to 700 °C at a heating rate of 10 °C min−1. The magnetic hysteresis loops were measured using a LakeShore 7404 vibrating sample magnetometer (VSM).Powder X-ray diffraction (XRD) patterns were obtained by a Shimadzu XRD-6100 diffractometer with Cu Kα radiation, employed a scan step of 0.02° in the 2εr and relative complex permeability μr) were measured by coaxial line method using an Agilent N5224A vector network analyzer (VNA) in the frequency range of 2–18 GHz. Based on the measured εr and μr, the RL curves at different absorbent thickness were calculated according to the following equations:24,25Zin is the input characteristic impedance of absorbent, Z0 is the characteristic impedance of free space, f is the frequency of electromagnetic wave, d is the thickness of absorbent, and c is the velocity of light.For microwave absorption measurement, the synthesized products were mixed with paraffin in the mass fraction of 33%, and then pressed into compact cylindrical specimens with an inner diameter of 3.00 mm and an outer diameter of 7.00 mm in the abrasive tool. The electromagnetic parameters , (200) and (220) crystalline planes of Ni (JCPDS No. 04-0850), respectively. That is to say, the Ni crystal is formed by in situ carbothermal reduction reaction. In addition, as can be seen from the XRD patterns, the Ni diffraction peaks enhance with the increase of Ni(NO3)2 concentration, indicating the increase of Ni nanoparticles content.3)2 aqueous solution, Ni(NO3)2 aqueous solution is easy to permeate into the surface and pores of jute fibers. Then, the jute fibers are converted into porous carbon fibers under constant flow of N2 at high temperature, and the decomposition products of Ni(NO3)2 react with porous carbon fibers, and the Ni nanoparticles are deposited on porous carbon fibers. It is believed that the amorphous carbon and the porous structure prevent the agglomeration of the Ni nanoparticles. In addition, by changing Ni(NO3)2·6H2O to Co(NO3)2·6H2O in the synthesis route, Co nanoparticles can also be loaded on porous carbon fibers  of Ni/C-0.2, Ni/C-0.5, and Ni/C-1.0 was 4.71, 10.53, and 20.33 emu g−1, respectively, which is highly dependent on the content of Ni nanoparticles on Ni/C porous fibers. In addition, the MS value of Ni/C porous fibers is lower than that of pure Ni of 55 emu g−1,27 which is mainly attributed to the nonmagnetic porous carbon fibers and particle size of Ni nanoparticles.The magnetic hysteresis loops of Ni/C-0.2, Ni/C-0.5, and Ni/C-1.0 were measured by VSM at room temperature. As indicated by the magnetic hysteresis loops in 3.2in situ template method. For investigating the microwave absorption performance of PCF and Ni/C porous fibers, the frequency dependence of the electromagnetic parameters were obtained from the VNA. It is generally true that the RL value of −10 dB represents 90% incident microwave is absorbed, and the effective bandwidth means the width of the frequency range when the RL is −10 dB. 28 For PCF, the minimum RL is −30.3 dB with a thickness of 2.0 mm, and the effective bandwidth is 4.4 GHz (from 11.16 to 15.56 GHz), as shown in 29–34 Moreover, in contrast with the traditional microwave absorbents, the Ni/C porous fibers present the advantage of low density due to the existence of porous carbon fibers. Considering that our synthetic method is simple, low cost, and suitable for large-scale preparation, it is attractive for microwave absorption application.Through the above results, using low-cost jute fiber as carbon source and template, Ni nanoparticles with different contents were successfully deposited on porous carbon fibers by an εr = ε′ − jε′′) and the relative complex permeability (μr = μ′ − jμ′′), and ensure that the electromagnetic wave can enter into the absorbent effectively. The real parts of the complex permittivity (ε′) and the complex permeability (μ′) stand for the stored electrical and magnetic energy, while the imaginary parts of the complex permittivity (ε′′) and the complex permeability (μ′′) correspond to the dissipation of electrical and magnetic energy.35,36 The electromagnetic wave attenuation is mainly reflected by the dielectric loss factor (tan δe = ε′′/ε′) and magnetic loss factor (tan δm = μ′′/μ′), and ensure that the absorbent can effectively attenuate the electromagnetic wave energy in its interior. ε′ values of PCF, Ni/C-0.2, and Ni/C-0.5 tend to decrease continuously with the increase of frequency. However, the ε′ value of Ni/C-1.0 decreases slowly in the frequency range of 2–10 GHz and then remains stable with the increase of frequency. Moreover, the ε′ values of Ni/C-1.0 is the smallest, showing minimum electrical energy storage. The ε′′ values of PCF, Ni/C-0.2, Ni/C-0.5, and Ni/C-1.0 are shown in ε′′ values show two distinct vibration peaks in the frequency range of 6–12 GHz and 12–16 GHz. The ε′′ value of Ni/C-1.0 is smaller than that of PCF, Ni/C-0.2, and Ni/C-0.5, showing minimum electrical energy loss. Moreover, from the free electron theory, ε′′ = 1/(2πρfε0), where ρ is the resistivity, f is the microwave frequency, and ε0 is the permittivity of vacuum.37 It can be speculated that a higher value of ε′′ corresponds to a lower resistivity. In this case, the loading of Ni nanoparticles on Ni/C porous fibers can enhance the conductivity, resulting in the increase of ε′′. However, if the loading content of Ni nanoparticles is too high, which may interrupt the conductive interconnection and reduce the conductivity of Ni/C porous fibers. For PCF, Ni/C-0.2, Ni/C-0.5, and Ni/C-1.0, the μ′ and μ′′ of complex permeability are displayed in μ′ and μ′′ show same trend with three obvious fluctuations. With increasing the content of Ni nanoparticles, the μ′′ values present an increasing trend, which is consistent with the content of Ni nanoparticles on Ni/C porous fibers and the VSM results. The low permeability is mainly due to the low loading of magnetic components and the low filling content of Ni/C porous fibers in paraffin matrix. Generally speaking, natural resonance, exchange resonance and eddy current effect are the main causes of magnetic loss in GHz band. Eddy current loss is related to the particle diameter (d), electric conductivity (σ) and vacuum permeability (μ0), which can be expressed by μ′′ ≈ 2πμ0μ′2σd2f/3. If the eddy current effect dominates the magnetic loss mechanism, the value of C0 = μ′′μ′−2f−1 remains constant with changing frequency.38C0–f curves of PCF, Ni/C-0.2, Ni/C-0.5, and Ni/C-1.0. It is obvious that they all show three obvious fluctuations in the frequency range of 4–8 GHz, 9–14 GHz and 15–18 GHz, which proves that the eddy current loss is not the main contributor to the magnetic loss. Besides, it can be concluded that the resonance peaks at 12 GHz and 16.5 GHz are related to the exchange resonance, and the peak at 6 GHz is attributed to the natural resonance.39 In addition, μ′′ has negative value in high frequency band. According to the Maxwell equations, the motion of free charges can produce AC electric field, and the magnetic field can be induced by AC electric field.40 Therefore, we speculate that the negative μ′′ value indicates that the magnetic energy is radiated out from the Ni/C porous fibers, and this negative μ′′ phenomenon has also been observed in many high conductivity absorbents.41,42According to the electromagnetic energy conversion principle, the microwave absorption of the absorbent is mainly determined by impedance matching and electromagnetic wave attenuation. The impedance matching is determined by the relative complex permittivity , and the Cole–Cole semicircle is mostly due to the polarization relaxation loss. ε′ versus ε′′ for PCF, Ni/C-0.2, Ni/C-0.5, and Ni/C-1.0 in the frequency range of 2–18 GHz, and all the four samples have more than one semicircle, showing evident polarization relaxation loss, which is good for dielectric loss. The ε′–ε′′ curves of PCF and Ni/C-0.5 have two Cole–Cole semicircles, while Ni/C-0.2 and Ni/C-1.0 have three and four Cole–Cole semicircle respectively, which indicates that the interface polarization effect of Ni/C-0.2 and Ni/C-1.0 is more obvious.According to Debye theory, the dielectric loss mainly originates from conduction loss and polarization relaxation loss, and the polarization relaxation loss is responsible for the several fluctuations of curves of The filling content of Ni/C porous fibers in the paraffin matrix is also an important parameter affecting the microwave absorption performance. Fig. S411 The SEM images of the porous fibers/paraffin composites were shown in Fig. S6.Based on the above experimental results and analyses, a possible microwave absorption mechanism of Ni/C porous fiber is elucidated in 4.via a simple in situ template method by using low-cost jute fiber as carbon source and template. The as-prepared Ni/C porous fibers showed hollow internal cavity and porous structure, and the Ni nanoparticles were relatively dispersed on the surface and hollow porous structure of the Ni/C porous fibers. Due to the proper filling content, the synergistic effect of dielectric loss, interface polarization loss, magnetic loss and porous structure, the synthesized Ni/C porous fibers exhibited excellent microwave absorption performance. Under the matching thickness (1.5–3.5 mm), all of the values of the RL peaks were below −20.0 dB. This method has the advantages of low cost, abundant resources, simple technology, good repeatability, and suitable for large-scale preparation, which can not only provide a new way to design other types of excellent microwave absorbing materials, but also offer an effective way to synthesize biomass nanocomposites.In summary, Ni/C porous fibers were successfully prepared There are no conflicts to declare.RA-010-D0RA06817A-s001


The results showed that low temperature  and near freezing-point temperature  storage effectively inhibited the decay of T. sinensis bud compared to room temperature . The combined treatments of BR with LT or NFPT reduced nitrite content and maintained the color and the contents of vitamin C, carotenoids, saponins, β-sitosterol, polyphenol, anthocyanin, flavonoids, and alkaloids in T. sinensis bud. BR soaking delayed the occurrence of chilling injury during NFPT storage. Meanwhile, BR soaking enhanced the DPPH radical scavenging activity, ABTS activity, and FRAP content by increasing SOD and POD activity and the contents of proline, soluble, and glutathione, thus decreasing MDA and hydrogen peroxide content and the rate of superoxide radical production in T. sinensis bud during NFPT storage. This study provides a valuable strategy for postharvest T. sinensis bud in LT and NFPT storage. BR soaking extended the shelf life during LT storage and maintained a better appearance and nutritional quality during NFPT storage.Low temperatures are often used to preserve fruits and vegetables. However, low-temperature storage also causes problems, such as chilling injury, nitrite accumulation, and browning aggravation in plants. This study investigated the effects of brassinolide (BR,1.0 mg L Toona sinensis bud is a pollution-free vegetable with a unique flavor and rich nutrition, including high protein, carbohydrates, and many kinds of vitamins, minerals, flavonoids, polyphenols, alkaloids, and other important bioactive components [T. sinensis bud had a variety of diet therapy functions. In relevant experiments, the quercetin in T. sinensis bud can alleviate oxidative-stressful response in the body and the damage of hepatocyte organelles in diabetic mice, which is expected to become an auxiliary substance in the treatment of diabetes [T. sinensis can induce the apoptosis of osteosarcoma cells and inhibit the abnormal growth of tumors [T. sinensis bud is prone to wilting, browning, defoliation, and decay [T. sinensis bud is vital.mponents ,2. Zhangmponents  reporteddiabetes . The aquf tumors . Howevernd decay . TherefoLow temperature  and near freezing-point temperature  are often used to preserve fruits and vegetables. However, LT or NFPT storage also causes problems, such as chilling injury, nitrite accumulation, and browning aggravation in horticultural crops ,8,9. TheIt has been reported that the application of exogenous hormones has a positive effect on plant resistance to stress . BrassinT. sinensis buds. We hypothesized that BR treatment could reduce nitrite accumulation, maintain the fresh color, and increase the quality of T. sinensis bud during LT or NFPT storage, which will help improve the shelf-life performance of vegetables or fruits stored under LT or NFPT conditions.It is well known that nitrite has adverse effects on human health and is considered to be one of the essential carcinogenic factors in the human diet . TherefoT. sinensis bud stored at 20 °C and 20 °C + BR gradually turned green and rotted after six days of storage, with the increase in storage days  . This might be related to the decrease of nitrate reductase activity in T. sinensis buds during LT and NFPT storage by BR treatment.Nitrate reductase is the key rate-limiting enzyme for reducing nitrate to nitrite in plants . In the  < 0.01) . Therefoi et al.  showed tT. sinensis buds. Vitamin C is an important health-promoting compound in buds and is easily lost during storage [T. sinensis buds was enhanced by BR treatment during 4 °C storage and was higher than in the control. This finding is similar to the results obtained by Hu et al. [T. sinensis buds decreased with storage time during 4 °C storage. In addition, vitamin C content in T. sinensis buds treated with BR decreased first and then increased during −2 °C storage. Cold storage positively influenced vitamin C in blond orange varieties [T. sinensis was decreased by day 6 during 4 °C and −2 °C storage, compared to the control. Dietary saponins have been reported to prevent diseases caused by obesity [T. sinensis buds when stored at 4 °C but also did not alter the contents of vitamin C, carotenoid, saponins, and β-sitosterol. The same results were found during −2 °C storage.The degradation of nutritional compounds during postharvest storage of buds has become a major limiting factor, which greatly limits its market value. Therefore, it is worth prolonging the shelf life and keeping/improving the postharvest storage quality of  storage . In the u et al. , who reparieties . The incarieties ,35. Low arieties . These r obesity . The mai obesity . The preT. sinensis buds was decreased by day 3 during different temperature storage, compared to the control. BR increased the polyphenol content in T. sinensis buds during storage. The quality of apple juice was changed during storage in association with polyphenol oxidase activity [T. sinensis buds was increased by BR treatment during storage. The results were similar to that BR treatment enhanced the anthocyanin content in small black bean sprouts by 0.56-fold after 5 days of 4 ± 1 °C storage, compared to the control [T. sinensis buds may be due to decreased polyphenol oxidase activity by BR treatment. Moreover, anthocyanins are important flavonoids in plants, which help protect plants from the damaging effects of reactive oxygen species by serving as free radical scavengers under salt stress [T. sinensis buds under 4 °C and −2 °C storage, suggesting that BR treatment may reduce the cold damage during LT and NFPT storage by increasing the flavonoid content. The T. sinensis leaves are rich in alkaloids, which are important nutrients [p < 0.01)  . The alk storage .T. sinensis buds at different storage temperatures. In the present results, the SOD activity in T. sinensis buds was increased under BR treatment by day 9 during 4 °C storage. The results were similar to those of carambola fruit treated with BR during 4 °C storage, which increased SOD activity to delay the chilling harm [T. sinensis buds was decreased by BR treatment during −2 °C storage. In addition, the increased GSH content after BR treatment inhibited reactive oxygen species contents and lipid peroxidation [T. sinensis buds was decreased by BR treatment during 4 °C and −2 °C storage on day 3, and BR treatment maintained a similar soluble sugar content to the control during 4 °C and −2 °C storage by day 3. This might be related to the fact that BR treatment alleviated the response of T. sinensis buds to cold stress, thus reducing sugar metabolism under LT and NFPT storage.Exogenous BR treatment can improve the tolerance of fruits and vegetables to cold stress, such as peaches , grapeviing harm . BR treaing harm  observeding harm . BR treaing harm . The prexidation . Solublexidation . HoweverT. sinensis buds by FRAP, ABTS, and DPPH radical scavenging activity methods. We measured the changes in MDA content, hydrogen peroxide content, and the rate of O2−· production of T. sinensis buds under different storage temperatures after BR treatment. There was a negative correlation between the content of hydrogen peroxide and the DPPH radical scavenging activity  and ABTS activity   . These fla fruit . Other sg stress .T. sinensis buds during −2 °C storage. In addition, the BR treatment maintained a more original appearance color and decreased the nitrite content in buds during 4 °C and −2 °C storage. By day 9, the nutritional qualities of buds such as vitamin C, carotenoids, saponins, β-sitosterol, polyphenol, anthocyanin, flavonoids, and alkaloid contents were not significantly different between the combined treatments of 4 °C + BR storage and 4 °C storage. By day 6, the combined treatments of −2 °C + BR enhanced the β-sitosterol and anthocyanin contents compared to the combined treatments of 4 °C + BR storage but did not differ substantially in vitamin C, carotenoids, saponins, and polyphenols contents. Furthermore, BR treatment improved antioxidant capacity by increasing antioxidant enzyme activity and non-enzymatic antioxidant contents, which reduced the occurrence of chilling injury of T. sinensis under −2 °C storage. This study confirmed our hypothesis that BR treatment reduced nitrite accumulation, extended color change, and increased the quality of T. sinensis buds during LT and NFPT storage. It provides a convenient and economical method for vegetable and fruit storage.In summary, BR treatment delayed the occurrence of chilling injury in T. sinensis buds were harvested from Zhuozhou T. sinensis growing base, Hebei, China, in April 2021. Brassinolide was provided by ANPEL Laboratory Technologies  Inc. T. sinensis buds with uniform size, color and absence of disease, and other defects were chosen and conveyed to the laboratory instantly after harvesting. Buds were disinfected for 4 min in 1% sodium hypochlorite, washed, and aired. Half of the buds were soaked in BR solution with 1.0 mg L−1 for 2 h, while the other half was immersed in distilled water as the control group. The concentration and soaking time of BR was based on our preliminary experiments. The NFPT of T. sinensis buds was determined to be −2 ± 0.5 °C, according to Fan et al. [n et al.  and Yangn et al. . After sg for 10 min. The supernatant was measured at 538 nm, and the result was shown as μg g−1 fresh weight (FW).Nitrite content was assayed by the National Food Safety Standard of the People’s Republic of China (GB5009.33-2010). The bud samples (0.2 g) were ground in a saturated borax solution (5 mL) and cultivated for 15 min in a boiling water bath. The mixture contained potassium ferrocyanide, zinc acetate, and sample extraction and was centrifuged at 4507× −1, pH 7.4, 0.1 mol L−1), EDTA (1 mmol L−1), and cysteine (10 mmol L−1). After centrifugation, the mixture, including 0.2 mL supernatant, 0.5 mL potassium nitrate, and 0.3 mL NADH, was cultured for 30 min at 25 °C. 2 mL of sulfonamide reagent and 2 mL of α-naphthylamine were added to the mixture and were shook well. After 15 min, the absorbance value was measured at 520 nm, and the result was shown as U g−1 h−1 FW.Nitrate reductase activity was measured based on the previous report . The fre2SO4 (85%) was slowly added to the reaction solution and was instantly shaken. Vitamin C was determined by measuring the absorbance at 500 nm and was indicated as mg g−1 dried weight (DW).Vitamin C was determined according to the 24-dinitrophenylhydrazine method . Dried s−1 FW.Carotenoid content was determined based on the method described by Ghassemi-Golezani et al. . The sam−1 DW.Saponin was determined based on the previous report . Dried s−1 DW.β-sitosterol content was measured based on the previous report with minor modifications . Dried sg for 10 min. The reaction solution included 1 mL of supernatant, 3 mL phosphoric acid buffer (pH 6.8), and 1 mL of 0.1 mol L−1 iron potassium tartrate. The absorbance was taken at 540 nm after blending, and the data was calculated using a linear equation of the catechin standard curve. Polyphenol content was expressed as μg g−1 DW.Polyphenol content was determined using the method described by Jiang et al.  with a sg. The enzyme extract (0.1 mL) was added to the reaction mixture, including 0.1 mol L−1 phosphoric acid buffer with pH 6.5 and 0.01 mol L−1 catechol solution, followed by a water bath for 30 min at 30 ℃. The reaction was terminated with 20% trichloroacetic acid. The absorbance value was measured at 410 nm, and the result was shown as U g−1 h−1 FW.PPO activity was measured based on the previous report . Fresh s−1 h−1 FW.Anthocyanin content was analyzed with 5 mL of 1% HCl-methanol solution in darkness for 3 days . The abs3 colorimetry [3 . The absorbance was measured at 415 nm after 30 min, and the flavone content was calculated as g 100 g−1 DW.Flavone content was evaluated according to AlClorimetry . About 0−1 DW.The total alkaloid was assayed according to the report with tiny modifications . Dried s−1 boric acid buffer (pH 8.7) containing mercaptoethanol (5 mmol L−1) and polyvinylpolypyrrolidone (0.1%). The supernatant (0.5 mL) was mixed with the 1 mL phenylalanine (0.02 mol L−1) and 3 mL borate buffer and was cultured at 30 °C for 0.5 h. The absorbance value was measured at 290 nm, and the result was indicated as U kg−1 h−1 FW.PAL activity was measured based on the report . The fre−1) containing polyvinylpolypyrrolidone . The extracted solution pH for SOD and POD were 6.8 and 6.4, respectively. The homogenate was centrifuged at 12,000× g for 30 min at 4 °C. SOD reaction solution included of 0.05 mol L−1 sodium phosphate buffer (1.7 mL), 0.014 mol L−1 methionine (0.3 mL), 0.75 mmol L−1 NBT (0.3 mL), 1.0 μmol L−1 EDTA (0.3 mL), 20.0 μmol L−1 riboflavin (0.3 mL), and enzyme extract (0.1 mL). SOD activity was analyzed by monitoring 50% inhibition of nitro blue tetrazolium (NBT) photochemical reduction. The solution was measured at 560 nm, and the result was shown as U g−1 FW min−1.SOD and POD were determined using the NBT method and the guaiacol method, respectively . Fresh s−1 sodium phosphate buffer (2.7 mL), of 0.02 mol L−1 H2O2 (0.1 mL), 0.02 mol L−1 guaiacol (0.1 mL) as a substrate, and 0.1 mL of enzyme extract. The solution was measured at 470 nm, and the result was shown as U kg−1 FW min−1.POD reaction solution included 0.05 mol LProline was determined based on the method described by Xi et al. . The dri−1 FW.Glutathione was determined based on the method described by Ahmad et al. . The sam−1 DW.Soluble sugar was measured based on the report . Soluble−1, 5 mL) and was extracted in an ultrasonic bath. After centrifugation, the supernatant was added to 5 mL Coomassie bright blue solution. The absorbance value was measured at 595 nm, and the result was presented as mg g−1 DW.Soluble protein was measured with Coomassie bright blue . The samDPPH radical scavenging activity was performed, as reported by Xue et al. . The samA0 is the absorption value of the control (the ethanol replaced the sample solution); A1 is the absorption value of the sample; A2 is the absorption value of the sample under similar conditions as A1 with the ethanol replaced the DPPH solution.−1 FW. ABTS activity was measured by mixing a 20 μL sample solution with 4 mL ABTS mixture, and the solution was cultured for 6 min at room temperature in the dark. The absorbance was measured at 734 nm, and the results were expressed as mg g−1 FW.FRAP and ABTS radical cation decolorization were determined using the method described by Deng et al. . FRAP co−1 FW.MDA was measured by the thiobarbituric acid (TBA) reaction . Samples−1 sulfuric acid solution. The supernatant was measured at 415 nm, and the result was shown as μg g−1 FW.Hydrogen peroxide was measured based on the report . Fresh s2−· production was measured as described by Xi et al. [−1 g−1 FW min−1.The rate of Oi et al. . Fresh sp < 0.05). The Pearson correlation coefficient examined the relationship between anthocyanin, nitrate, nitrite reductase, and quality indices. The correlation data was made into a heat map by Origin 2019b software.Random sampling was used in all experiments. All data were obtained from the average of four repeated experiments. All data were statistically determined using SPSS 21.0, and the findings were analyzed using one-way ANOVA and Duncan’s test to see if there were significant differences (


Case report: A 64‐year‐old man was hospitalized in the intensive care unit with pneumonia, lactic acidosis, and hypoglycemia. Investigations revealed a kappa light chain multiple myeloma. The patient underwent chemotherapy by bortezomib, lenalidomide, and dexamethasone. Serum lactate level and glycemia normalized. Evaluation at day 28 showed a disease progression. Lenalidomide was switched for daratumumab, bortezomib, and dexamethasone. In front of the inefficiency of the chemotherapy, the patient underwent third‐line chemotherapy by melphalan. There was a correlation between the evolution of the myeloma, serum lactate level, and hypoglycemia, with a normalization after chemotherapy, and a rise at myeloma's relapse. Daratumumab was continued as a maintenance treatment. The patient died 4 months and 10 days after his first hospital admission.Discussion: Our case is consistent with a type B tumor‐associated aerobic glycolytic lactic acidosis, called the Warburg effect. It is well described in association with other hematologic malignancies, but rarely in association with myeloma. All reported cases of myeloma with type B lactic acidosis died within 1 year.Conclusion: When associated with multiple myeloma, tumor‐associated aerobic glycolytic lactic acidosis is correlated with the disease progression and has a very high mortality rate.Significance Statement : Aerobic glycolytic lactic acidosis also known as the Warburg effect can be encountered in multiple myeloma, resulting of a metabolic shift to increased glycolysis operating in malignant cells. Together with hypoglycemia, it is well correlated with the disease progression and has a very poor outcome. Malignant plasma cells invade the bone marrow and overproduce abnormal immunoglobulin or light chain protein, causing fatigue, weight loss, immunodepression, bone pain, hyperviscosity, anemia, hypercalcemia, and renal insufficiency. Multiple myeloma is the second most common hematologic malignancy and accounts for less than 2% of all cancers, with a median presentation age of 70 years , 2, 3. TA wide variety of metabolic disorders are observed in patients presenting hematological malignancies, such as hyperuricemia, hypercalcemia, hypo‐ or hyperglycemia, lactic acidosis, and inappropriate secretion of antidiuretic hormone syndrome . PathogeWe describe a case of multiple myeloma associated with high and recurrent hyperlactatemia and profound hypoglycemia.2A 64‐year‐old man, smoker, without any specific medical history or treatment, was admitted to the emergency department of our hospital in June 2019 with progressive dyspnea, bone pain, and a recent loss of 10 kg.On examination, blood pressure was normal (126/69 mm Hg), heart rate was raised to 107 beats/min, oxygen saturation was 97% while breathing room air, respiratory rate was raised to 23/min, and the temperature was 37°C. He had clinical signs of dehydration, spontaneous chest and dorsal pain, and vomiting. Laboratory findings showed hemoglobin at 10.5 g/dL , thrombocytopenia at 96 G/L (150–450 G/L), white blood cell count at 8.4 G/L (4–10 G/L), lymphopenia at 0.64 G/L (1–4 G/L), creatinine at 42 micromol/L (62–115 micromol/L), BUN at 5.9 mmol/L (3.8–8.2 mmol/L), natremia at 131 mmol/L (136–145 mmol/L), hypokalemia at 2.97 mmol/L (3.4–4.5 mmol/L), hypercalcemia at 3.59 mmol/L (2.18–2.6 mmol/L), bicarbonates at 15.7 mmol/L (22–28 mmol/L), hypophosphatemia at 0.69 mmol/L (0.78–1.65 mmol/L), hypoprotidemia at 42 g/L (57–82 g/L) with hypoalbuminemia at 26.8 g/L (32–46 g/L), ASAT at 44 U/L (13–40 U/L), ALAT at 30 U/L (7–40 U/L), and total bilirubin concentration at 11 micromol/L (3–19 micromol/L). computed tomography (CT) scan showed bilateral pneumonitis, multiple bone lesions of the spine, sternum and ribs, and no pulmonary embolism. The cardiac echography was normal. The patient received bisphosphonate and intra‐venous hyperhydration. On the next day, his respiratory condition worsened. The oxygen saturation rate lowered, and high‐flow nasal cannula oxygen therapy with FiO2 60% was initiated. Arterial blood gas showed respiratory alkalosis and lactic acidosis: pH 7.46, PCO2 23 mm Hg, PO2 65.2 mm Hg, bicarbonate 16.2 mmol/L, lactate 15 mmol/L. The patient was admitted to the ICU.Broad‐spectrum antibiotics (cefotaxime and spiramycine) were administered. Three days after the admission in ICU, the patient's condition worsened. A rapidly extensive pulmonary infection was suspected, that required intubation, mechanical ventilation, and norepinephrine infusion. Despite respiratory improvement and hemodynamic stabilization with normal cardiac output, intravenous hydration and thiamine course, serum lactate level remained between 10 and 15 mmol/L. The first attempt of osteomedullary biopsy was not contributive because of a very friable bone. Hypothesizing an aggressive hematological malignancy, intra‐venous corticotherapy of 1 mg/Kg a day was initiated on the 4th day after admission. As a result, tumor lysis syndrome occurred with hypocalcemia of 1.92 mmol/L, hyperphosphatemia of 1.79 mmol/L, hyperuricemia of 475 micromol/L, and acute kidney failure with creatinine of 189 micromol/L and hyperkaliemia of 5.22 mmol/L. Because of kidney failure with anuria, renal replacement therapy was started. In addition, serum lactate level decreased rapidly, although transiently with a new increase up to 15 mmol/L 1 week later, without clinical worsening. Concomitantly to re‐ascension of lactate, a deep hypoglycemia appeared, with an increasing need for glucose 30% infusion to maintain glycemia over 0.9 g/L , ISS score III. Genetic analysis was not performed.2, oral lenalidomide 25 mg once a day 21 d/28, and oral dexamethasone 40 mg. His condition progressively improved, norepinephrine and renal replacement therapy were stopped, and the patient was extubated. Serum lactate level, calcemia, and glycemia normalized, and the light chain ratio lowered to 3.94. However, evaluation at day 28 after the first chemotherapy showed a disease progression with a light chain ratio of 30.2, dFLC (difference of free light chains) of 491.2 and raised serum lactate level , calcemia, and glycemia normalized. Despite 15 days of aplasia complicated with a Clostridium difficile colitis, the patient's condition improved, and the tracheal tube was removed. On the 20th of September, after 3 months in the ICU, the patient was discharged to the hematology ward, with severe amyotrophy, polyneuropathy, and denutrition.Lenalidomide was then switched for second‐line chemotherapy with daratumumab 16 mg/kg, bortezomib and dexamethasone. The patient's condition worsened with the occurrence of a ventilator‐associated pneumonia by Daratumumab was continued as a maintenance treatment, and the patient was discharged to his home. Unfortunately, he was readmitted 17 days later with a febrile aplasia and bilateral pneumonia. Biological analysis showed a relapse of the myeloma with hypercalcemia of 2.64 mmol/L, a light chain ratio of 52.02, dFLC of 160.7 and raised serum lactate level to 12.8 mmol/L. Understanding his condition, the patient requested palliative care and subsequently died 4 months and 10 days after his first hospital admission.3Our patient presented a very invasive kappa light chain myeloma associated with severe hyperlactatemia and profound hypoglycemia. Serum lactate level decreased after chemotherapy and increased concomitantly with the myeloma relapses.Lactic acidosis is defined by an elevated blood lactate level, typically >5 mmol/L, depending on the laboratory norm. Acidemia is not constant in lactic acidosis, as coexisting acid‐base disorders can increase the blood pH . Lactic In normal aerobic conditions, glycolysis converts glucose to pyruvate, which is oxidized to acetyl‐CoA, releasing CO2 and entering the Krebs cycle. This reaction produces NADH, which is then used in oxidative phosphorylation and produces 36 molecules of ATP. Under anaerobic conditions, pyruvate is converted to lactate . The WarIncreased glycolysis also explains an often coexisting hypoglycemia with the Warburg effect , 21, 22.However, in a critically ill patient presenting a hematological malignancy with lactic acidosis and hypoglycemia, other diagnoses must be ruled out, before concluding to the Warburg effect. Our patient presented upon admission to the ICU a hypoxemic pneumonia with septic shock, which could explain lactic acidosis. However, despite hemodynamic and respiratory stabilization, serum lactate levels remained over 10 mmol/L. There was no evidence for mesenteric ischemia, no liver failure, no drugs inducing acidosis, and the patient was supplied with thiamine. Acute renal failure could not entirely explain lactic acidosis, as lactate level remained over 5 mmol/L despite continuous renal replacement therapy. We observed a correlation between the evolution of the myeloma, serum lactate level, and hypoglycemia, with a decreasing of the lactate level and normalization of glycemia after the administration of corticosteroids and chemotherapy, and a rise of serum lactate level and hypoglycemia at myeloma's relapse (Figure Interestingly, to the best of our knowledge, this case is the first description of a newly diagnosed myeloma immediately associated with type B lactic acidosis, as all other cases reported myelomas evolving for several years, with lactic acidosis appearing only in relapses Table . This coAerobic glycolytic lactic acidosis and hypoglycemia are serious metabolic abnormalities encountered in hematological malignancies, resulting from changes in the metabolic pathway of the malignant cells. When associated with multiple myeloma, this condition is correlated with the disease progression and has a very high mortality rate.All authors were involved in the management of the patient. Caroline Ziegler, Lev Volkov, and Agnès Melone collected the data. Caroline Ziegler, Lev Volkov, Aurore Perrot, and Sébastien Gibot wrote the manuscript.The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.


Brassica napus L. var. napus). A one-factor field experiment conducted on podzolic soil  showed that the use of biomass combustion ash significantly improved soil moisture at all depths and variants, and especially at a depth of 30–35 cm in the 500 kg·ha−1 variant, i.e., by 2.99% v/v, compared to NPK. In turn, the moisture content in the 30–35 cm layer increased by 3.19% v/v in all variants in both years compared to the control. In 2020 and 2021, bulk density in the 0–5 cm layer treated with a dose of 500 kg·ha−1 exhibited a positive 0.15 and 0.12 Mg·m−3 decrease, respectively, compared to the control. In both years, the BD values in the 30–35 cm layer were reduced by 0.14 and 0.16 Mg·m−3 compared to the control. The PR values decreased in the treatments with doses of 300, 400, and 500 kg·ha−1, especially in 2021. The RDC content was found to decline in both years, i.e., 2020 and 2021, upon the application of even the lowest dose (100 kg·ha−1) in all the analysed layers. The reduction in the RDC content, especially in the 0–5 cm layer, is very important for soil structure stability and to protect the soil environment. This layer is most susceptible to crusting, which results in poor aeration and weak plant emergence during drought and/or periods of excessive moisture. It may also increase surface runoff and intensify soil erosion processes.This two-year study was focused on the effect of the application of different biomass ash doses on selected soil physical properties, i.e., soil moisture (SM), bulk density (BD), penetration resistance (PR), and soil stability in water measured by the content of readily dispersible clay (RDC), following control and mineral NPK fertilization in the cultivation of winter oilseed rape ( Wood ash, i.e., the product of the complete combustion of woody materials, can be used in plant nutrition and nutrient cycling in agriculture ,2. SinceResearch on the application of biomass ash on crop soils was conducted by the authors of . Other sBiomass combustion ash is increasingly being used in agriculture as a fertilizer due to its beneficial effects on soil, i.e., improvement of biological and chemical properties; however, few studies have been published on the impact of ash on soil physical properties. Properties such as soil moisture content (SM), soil bulk density (BD), penetration resistance (PR), readily dispersible clay (RDC), soil stability in water, etc., are among of the most important parameters ,20,21,22In their study, Bonfim-Silva et al.  demonstrAnother important parameter is bulk density (BD), which is an indicator of soil compaction. BD has an impact on infiltration, rooting depth, available water capacity, porosity, soil aeration, the availability of nutrients for plant use, and the activity of soil microorganisms, all of which affect key soil processes. Bulk density (BD) is not an intrinsic property of soil, but rather, depends on external conditions, i.e., various natural and anthropogenic factors . It is aAnother parameter, i.e., the content of readily dispersible clay (RDC), is closely related to soil bulk density (BD) and penetration resistance. According to Gajda et al. , RDC parThe aim of this study was to determine the effect of the application of different biomass ash doses on soil properties, such as moisture content, bulk density, penetration resistance, and soil stability in water measured by the content of readily dispersible clay, versus NPK mineral fertilization and control variants for the cultivation of winter oilseed rape.The investigations sought to verify the hypothesis that the use of different doses of biomass ash would have a positive effect on soil by improving its physical properties.Brassica napus L. cultivar Mandril (Syngenta) in 2018 (autumn) in Korzenica, Jaroslaw county (Podkarpackie voivodeship in Poland) GPS coordinates: 50.02′0.238″ N, 20.22.55′0.198″ E; 50.02′0.198″ N, 20.55′0.124″ E. The podzolic soil had the particle size distribution of silty loam (Field experiments were performed on a property on podzolic soil under lty loam . The gra2) was applied in triplicate. The dose of biomass combustion ash fertilizer  was the experimental variable. The obtained results were compared with a control soil—i.e., without fertilization and with soil subjected exclusively to NPK mineral fertilization. The biomass ash doses were balanced to the amount of potassium introduced into the soil. All the variants were treated with constant mineral fertilization with nitrogen (81.3 kg N ha−1) and phosphorus (34 kg P ha−1). Variants of the experiment were as follows:-2O fertilization;Control—no K-2O in mineral fertilizers (127 kg K2O ha−1);NPK—K-2O ha−1 in ash;W1—100 kg K-2O ha−1 in ash;W2—200 kg K-2O ha−1 in ash;W3—300 kg K-2O ha−1 in ash;W4—400 kg K-2O ha−1 in ash.W5—500 kg KAs a single-factor field experiment, the randomized block method  or in plastic bags  content).3. Soil moisture and bulk density were measured in the laboratory by weighing the soil samples before and after drying at 105 °C in an oven for 48 h.For the determination of SM and BD, samples were collected in 10 replicates from the 0–5 and 30–35 cm layers into cylinders with a volume of 100 cmv/v)wm—wet soil mass (g)dm—weights of oven-dry soilst—tare of cylinder (g)100—volume of the cylindrical core.The soil moisture, SM, values were then calculated as a % volume using the following equation:−3)dm—weights of oven-dry soils,100—volume of the cylindrical core.Bulk density (BD) was determined after drying the core samples in an oven at 105 °C for 48 h and calculated as:A total of 840 samples were measure for bulk density (2 depths × 10 replications × 3 plots × 2 years × 7 treatment) and 840 samples for gravimetric soil moisture (2 depths × 10 replications × 3 plots × 2 years × 7 treatment).PR (Pa or MPa or N·m−2), is defined as the force, P (N), required for cone penetration divided by the area A (m2) of the widest part of the cone:Soil penetration resistance, 2 diameter and a 30° angle cone. Penetration resistance was recorded automatically at 1 cm intervals. Since the penetration resistance is variable, ten parallel measurements were performed for each experimental variant. The median was calculated from each measurement. The total number of penetrations was 420 (7 treatments × 10 replicates × 3 plots × 2 years). In total, 420 soil compactness measurements to a depth of 80 cm were analysed.Soil penetration resistance, PR was measured using an automatic penetrologger  with a 1 cmSoil samples for the determination of readily dispersible clay (RDC) were collected at the following depths: 0–5, 5–10, 10–15, 15–12, 20–25, 25–30 and 30–35 cm. This parameter was determined using the method described by Czyż and Dexter . Soil stMeteorological data for 2019–2021 were provided by the University of Rzeszow meteorological station.p < 0.03) using Tukey HSD multiple comparisons test.The obtained results were analysed using STATISTICA 13.3 software . One-way analysis of variance (ANOVA) was performed to identify homogeneous groups , the difference in total precipitation was 100.1 mm. There was 7.3 mm of precipitation in 2020 and 107.4 mm in 2021. The average air temperature during the 2019/2020 growing season was 10.8 °C; in 2020/2021, this was 0.7 °C lower than in the first year, averaging 10.1 °C.The total precipitation in the studied years, i.e., 2019–2021, varied : in 2019The most important water properties of soils include current moisture, water capacity, plant–available water retention, and water conductivity ,43. Curr−1) in the 0–5 cm layer was 1.88% v/v in favour of ash application. In 2021, the soil moisture in the same layer was 2.02% v/v higher. A similar increase in moisture was recorded in all variants and layers; however, the 30–35 cm layer exhibited a 3.35% v/v increase in W5 versus NPK in 2020. In 2021, higher water content was recorded at all layers and variants, with a particularly large increase (by 2.99% v/v) in W5 versus NPK at the depth of 30–35 cm. The experiment showed that increasing biomass ash dose resulted in a significant increase in the water content in the soil in the 0–5 and 30–35 cm layers. Similarly, Pereira et al. [The present experiment demonstrated  that soia et al.  reported−3 in 2020 and by 0.12 Mg·m−3 in 2021, compared to the control. There was also a downward trend in the BD value by 0.14 Mg·m−3 in the 30–35 cm layer in 2020, compared to the control. In the second year of the experiment (2021), the value of this parameters decreased by 0.16 Mg·m−3, compared to the control. Moreover, a downward trend was found in the variants of fertilization, especially in W4 and W5, compared to the NPK treatment in both years. A study conducted by Bonfilm-Silva et al. [Bulk density (BD) is the most frequently used parameter to assess soil compaction. It is also regarded as an indirect indicator of soil structure, penetration resistance, porosity, aeration, and soil capacity to store and transport soil water . An incra et al.  unequivo−1 had a beneficial effect, i.e., they reduced the compactness of the podzolic soil, especially at a depth of 30–35 cm in 2021  have been focused on the influence of these materials on the chemical properties of soil, whereas the issue of soil physical properties has been poorly explored.−1 of biomass ash. The application of ash significantly improved soil moisture and reduced the content of readily dispersible clay, thereby increasing soil stability in water, which is important for the prevention of soil erosion.The present study shows that biomass ash has a positive effect on the physical properties of soil, i.e., soil moisture, bulk density, penetration resistance, and reduction of readily dispersible clay content. These results allow us to conclude that the use of biomass ash, especially in high doses, reduces soil bulk density. We also recorded lower values of penetration resistance in podzolic soil at doses of 300–500 kg·haIn general, the use of biomass ash improved all the analysed physical properties of podzolic soil. Biomass combustion ash may become an alternative fertilizer that is capable of improving the physical properties of soil, which are currently underestimated and poorly studied.


Scientific Reportshttps://doi.org/10.1038/s41598-020-67032-3, published online 23 June 2020Correction to: The original version of this Article contained an error in Figure 1, where the width dimension of the testing apparatus was incorrect.The original Figure As a result, in the Materials and methods, under the sub-heading ‘Experimental design’,"The testing apparatus was constructed out of wood and measured 6.9 m long by 0.3 m wide, as depicted in Fig. 1."now reads:"The testing apparatus was constructed out of wood and measured 6.9 m long by 0.59 m wide, as depicted in Fig. 1."The original Article has been corrected.


Mortierella is often found in the plant rhizosphere, and its possible functions are not well known, especially in medical plants. Mortierella alpina isolated from ginseng soil was used to investigate its effects on plant disease. The promoting properties and interactions with rhizospheric microorganisms were investigated in a medium. Further, a pot experiment was conducted to explore its effects on ginseng root rot disease. Physicochemical properties, high-throughput sequencing, network co-occurrence, distance-based redundancy analysis (db-RDA), and correlation analysis were used to evaluate their effects on the root rot pathogen. The results showed that Mortierella alpina YW25 had a high indoleacetic acid production capacity, and the maximum yield was 141.37 mg/L at 4 days. The growth of M. alpina YW25 was inhibited by some probiotics  and potential pathogens , but it did not show sensitivity to the soil-borne pathogen Fusarium oxysporum. Pot experiments showed that M. alpina could significantly alleviate the diseases caused by F. oxysporum, and increased the available nitrogen and phosphorus content in rhizosphere soil. In addition, it enhanced the activities of soil sucrase and acid phosphatase. High-throughput results showed that the inoculation of M. alpina with F. oxysporum changed the microbial community structure of ginseng, stimulated the plant to recruit more plant growth-promoting bacteria, and constructed a more stable microbial network of ginseng root. In this study, we found and proved the potential of M. alpina as a biocontrol agent against F. oxysporum, providing a new idea for controlling soil-borne diseases of ginseng by regulating rhizosphere microorganisms.Plant-associated microbes play important roles in plant health and disease.  Panax ginseng C. A. Meyer), a member of the Araliaceae family, is a valuable medicinal plant with multiple functions, such as enhancing organ functioning, inhibiting inflammation, preventing tumors and diseases, and potentially inhibiting COVID-19  the effects of inoculation of native M. alpina on ginseng and rhizosphere soil; (2) whether M. alpina has the ability to help plants resist the invasion of pathogens; and (3) if it does, how is the underlying mechanism?Here, an Mortierella alpina YW25 was isolated from ginseng rhizosphere soil, and F. oxysporum YFW32 was isolated from diseased ginseng roots. The above strain sequences were been stored in DDBJ/EMBL/GenBank using DDBJ quick annotation and submission tool (DFAST),M. alpina YW25. Briefly, six PDA plugs with M. alpina YW25 mycelia (5 mm diameter) were inoculated in flasks containing 100 ml PDB liquid medium and 3 mM tryptophan. The flasks were maintained at 28°C for 2–7 days at 180 rpm. Uninoculated medium was used as the control. Then, 2 ml of culture was centrifuged at 10,000 rpm and 4°C for 10 min. The supernatant was mixed with Salkowski reagent in equal volumes, and the reaction was developed at 25°C in the dark for 30 min. The absorbance was measured at 535 nm. A calibration curve was established for calculating IAA concentration (5–100 mg/L) at 535 nm using pure IAA. The values were averaged over triplicates.The Salkowski colorimetric method  was usedM. alpina YW25 inorganic phosphorus was evaluated using Pikovskaya’s (PVK) medium (4)2SO4, 0.3 g MgSO4·7H2O, 0.03 g MnSO4·4H2O, 0.03 g FeSO4·7H2O, 5 g Ca3(PO4)2, 18 g agar, and 1 L distilled water, and was adjusted to pH 7.0–7.2. M. alpina YW25 was inoculated into plates containing PVK agar medium. The inoculated plates were incubated in the dark at 28°C for 7 days. Clear halos were observed around the colonies, which indicated that the isolate solubilized inorganic phosphate. Lecithin  was used instead of Ca3(PO4)2 to evaluate its ability to dissolve organophosphorus (The solubility of ) medium . The 1 Losphorus . This waM. alpina YW25. PDA plugs with M. alpina YW25 mycelia (5 mm diameter) were inoculated on CAS plates and incubated at 28°C for 7 days. The formation of an orange halo around the colony was observed. Larger halos had darker colors, which indicated a higher yield of siderophores. Six PDA plugs with M. alpina YW25 mycelia were inoculated in 100 ml of PDA liquid medium. The flasks were maintained at 28°C for 7 days at 180 rpm. Subsequently, 2 ml of culture at 4°C was centrifuged at 10,000 rpm for 10 min. The supernatant was mixed with CAS solution in equal volumes, and the reaction was carried out at 25°C in the dark for 1 h. The absorbance was detected at 630 nm (A), and the uninoculated medium was used as the control (Ar). Siderophores produced by the isolate were measured as percent siderophore units (% SU), and were calculated according to the following formula: % SU = (Ar–A) ÷ Ar × 100. The values were averaged over triplicates  was added to the plates containing 0.5% carboxymethyl cellulose and 0.5% xylan. Following this, the plates were washed with 1 M NaCl. Yellow halos were observed around the colonies, which indicated cellulase and xylanase activities, respectively. When 1% cetyl trimethyl ammonium bromide (CTAB) was added to the plate containing 1% pectin, a transparent halo appeared around the colony, which indicated pectinase activity. After the fungi were cultured on PDA plates containing 1% skim milk powder, a transparent hydrolytic halo appeared around the colony, which indicated protease activity  were inoculated in flasks containing 100 ml YM liquid medium (2CO3 was then mixed with the supernatant (1 ml) and after 10 min, 1 ml of Folin reagent was added to each tube. The tubes were allowed to stand for 30 min at 30°C and then the absorbance was measured at 660 nm. Similar approach was used to prepare the control except casein was added only after the reaction was stopped. 1 U = the amount of enzyme required to liberate one microgram (1 μg/ml) of tyrosine under the assay conditions described  = (colony radius of control group − colony radius of treatment group)/colony radius of control group × 100 , + (inhibition rate < 30%), ++ (inhibition rate 30–60%), and +++ (inhibition rate > 60%).The interaction between n method . The 17 up × 100 . The inhM. alpina YW25 and F. oxysporum YFW32 with a diameter of 5 mm were cultured for 7 days at 28°C in PDA liquid medium separately at 180 rpm. The mycelium was filtered using gauze and diluted with sterile water to prepare a 1.2 × 107/ml spore suspension, which was used for pot inoculation of ginseng. Three treatment groups were established: single inoculation of M. alpina YW25 (MA), single inoculation with F. oxysporum YFW32 (FO), and inoculation with M. alpina YW25 and F. oxysporum YFW32 (MA_FO).The PDA plugs containing mycelia of M. alpina YW25 and F. oxysporum YFW32 spore suspensions were inoculated with 5 ml each, and 10 ml sterile water was used as the control (CK). The setup for each treatment was repeated five times.Potted soil (not autoclaved) contains 25.05 mg/kg nitrate nitrogen, 0.69 mg/kg ammonium nitrogen, 1.18 mg/kg available phosphorus, 292.25 mg/kg available potassium, total nitrogen 10.2 mg/g, total phosphorus 8.59 mg/g, total potassium 20 mg/g, and organic matter 0.35 g/g and the pH was 6.96. Three-year-old ginseng seedings were planted in each pot and inoculated by root irrigation. In MA and FO treatments, each pot (1.5 kg flower soil) was inoculated with 10 ml spore suspension. In MA_FO treatment, Ginseng was harvested after 70 days of pot planting. It was carefully uprooted and gently shaken to remove loosely adhered soil from the roots. Subsequently, all ginseng rhizosphere soil samples from the same treatment were mixed, and the rhizosphere soil sample of the treatment was formed. The rhizosphere soil samples were divided into two parts, and one of these was immediately stored in a −80°C refrigerator for the detection of soil microbial diversity. The other was air-dried indoors and stored at room temperature after filtering through a 2 mm sieve for determination of various soil physical and chemical properties. After washing and drying five ginseng plants in each treatment, the length and fresh weight of ginseng plants were measured by scale and balance. The ginseng plants were then divided into root and aboveground parts. After surface disinfection, the samples were quickly frozen in liquid nitrogen and then stored at −80°C for the detection of ginseng microbial diversity and plant defense enzymes.3 extraction and molybdenum–antimony resistance spectrophotometry . Nitrate and ammonium nitrogen were determined by 2 mol/L KCl extraction spectrophotometry . Availabotometry . Kjeldahotometry . Total potometry . Total potometry , and orgotometry . Soil urotometry , and theotometry .Harvested fresh ginseng root tissue was used to detect plant defense enzymes. The activities of peroxidase (POD), polyphenol oxidase (PPO), lipoxygenase (LOX), and phenylalanine ammonia lyase (PAL) were determined using microplate kits . The raw reads were deposited into the NCBI sequence read archive (SRA) under the submission ID SUB10895992.High-throughput Illumina sequencing was used to characterize the microbial community structure in the soil and plant samples . The V3-V4 regions of the soil bacterial 16S rRNA genes were amplified using the primers 338F (5′-ACTCCTACGGGAGGCAGCAG-3′) and 806R , and 10 ng template DNA in a 20 μl reaction volume. The thermal cycling conditions for prokaryotic 16S rRNA gene from soil bacteria fragment amplification were as follows: 3 min at 95°C, 30 cycles of 30 s at 95°C, 30 s at 55°C, 45 s at 72°C, and 10 min at 72°C. The 16S rRNA gene from ginseng bacterial fragments was amplified in two rounds, and the thermal cycling conditions of amplification were as follows: first round: 3 min at 95°C, 27 cycles of 30 s at 95°C, 30 s at 55°C, 45 s at 72°C; and 10 min at 72°C; second round: 3 min at 95°C, 13 cycles of 30 s at 95°C, 30 s at 55°C, 45 s at 72°C, and 10 min at 72°C. Fungal PCR reactions were performed in triplicate with 2 μl 10× rTaq Buffer, 2 μl 2.5 mM dNTPs, 0.8 μl 5 μM forward primer, 0.8 μl 5 μM reverse primer, 0.2 μl rTaq polymerase, 0.2 μl BSA, and 10 ng template DNA in a 20 μl reaction volume. The thermal cycling conditions for prokaryotic ITS gene fragment amplification were as follows: 3 min at 95°C, 30 cycles of 30 s at 95°C, 30 s at 55°C, 45 s at 72°C, and 10 min at 72°C. The PCR products were identified by 2% agarose gel electrophoresis, purified using an AxyPrep DNA gel extraction kit , and quantified using a QuantiFluor™-ST Blue Fluorescence Quantification System (Promega).The amplified sub-library was sequenced on an Illumina PE250 platform . The effective sequences of all samples were obtained according to the barcode, and Trimmomatic , and the significance level was M. alpina YW25, the capacities of IAA and siderophore production, phosphorus solubilization, and hydrolase activity of M. alpina YW25 were determined. The results showed that it had a high ability to produce IAA, and the highest IAA concentration in PDB liquid medium containing 3 mM tryptophan reached 141.37 mg/L at 4 days  significantly inhibited the growth of M. alpina YW25 among the 15 bacterial strains isolated from the ginseng rhizosphere. Streptomyces tricolor and Brevibacterium frigoritolerans (actinomycetes) also showed significant inhibition of M. alpina YW25. Fungi isolated from ginseng rhizosphere, such as Trichoderma koningiopsis, T. viridescens, T. harzianum, T. velutinum, Rhizopus oryzae, Penicillium citrinum, P. chrysogenum, Aspergillus ochraceus, A. flavus, Cladosporium anthropophilum, and C. cladosporioides, also inhibited the growth of M. alpina YW25. However, there was no obvious interaction between F. oxysporum YFW32 and M. alpina YW25.The interaction between M. alpina YW25 inoculation on ginseng, plant height, root length, and fresh weight of both aboveground and root regions were measured (p < 0.05), and there was no significant difference between MA and CK. There was no significant difference in fresh weight of ginseng aboveground. The fresh weight of ginseng roots in FO was significantly lower than that in the other treatments. The fresh weight of ginseng roots in CK was significantly higher than that in MA, but there was no significant difference between CK and MA (p < 0.05). LOX activity was significantly lower, whereas PAL activity showed no significant change. Compared with CK, the activities of PPO, LOX, and PAL in the MA_FO were higher, but the activities of the four plant defense enzymes in the MA and MA_FO treatments were not significantly different (To determine the effects of measured . The defmeasured . In the measured . GinsengK and MA . In the ifferent .4+-N), nitrate nitrogen (NO3−-N), total nitrogen (TN), available phosphorus (AP), total phosphorus (TP), available potassium (AK), total potassium (TK), urease (Urease), catalase (CAT), sucrase (SC), and acid phosphatase (ACP) were measured in ginseng roots . In the FO treatment, soil pH was significantly lower than that in CK, but the soil AK content was significantly higher than that of the other treatments (p < 0.05). The content of NO3−-N, AP, and AK in the MA_FO rhizosphere soil was significantly lower, but the content of NH4+-N was significantly higher than that in FO (p < 0.05). The available nitrogen (NH4+-N and NO3−-N) and AP content in the MA treatment was significantly higher than those in the MA_FO treatment. In addition, the activity of urease, SC, and ACP in MA soil was significantly higher, while the activity of CAT was significantly lower than that in CK (p < 0.05). The activities of CAT and SC in the MA_FO treatment were significantly higher, while the activity of ACP was significantly lower than that in FO.As shown in the table, there were no significant differences in pH, TN, and TP among the MA, MA_FO, and CK treatments. The NOp < 0.05) in all treatments. In the FO and MA treatments, soil fungal diversity was significantly lower than that in the CK and MA_FO treatments (p < 0.05). There was no significant difference between MA and CK in the diversity of bacteria and fungi in the aboveground parts of ginseng. In the MA treatment, the fungal diversity was significantly lower in the roots of ginseng than in CK and FO. Further, FO and MA_FO showed no significant differences in the diversity of bacteria in the aboveground parts of ginseng. Compared with FO, the bacterial diversity significantly increased, and the fungal diversity significantly decreased in the roots of ginseng in MA_FO (p < 0.05).The Shannon index was used to evaluate the soil microbial diversity of ginseng aboveground, roots, and rhizosphere under different treatments . The bacR2 = 0.2943, p = 0.001) and fungal  community structures in different parts of ginseng. Visual circos of microorganisms in aboveground and root of ginseng were constructed using bacteria and fungi genera, respectively, with relative abundance greater than 1% to evaluate the relationship between microorganisms and samples in different parts of ginseng . Compared with the FO treatment, the relative abundance of Sphingomona, Oxalobacteraceae, Fimbriimonadaceae, and Comamonadaceae in the MA_FO treatment was significantly increased , and there was no significant difference between the MA and MA_FO treatments. Compared to FO, the relative abundances of Pseudomonas, Comamonadaceae, Polaromonas, Novosphingobium, Dokdonella, Afipia, Rhizobium, Sphingomonas, Mycobacterium, and Parablastomonas increased significantly in ginseng roots after MA_FO treatment  and Cadophora (22% and 20%) in MA and MA_FO were lower than those in CK, and Tetracladium (41% and 24%) and Alatospora  were significantly higher than those in CK . The relative abundances of Flavobacterium, Marmoricola, Gaiella, and Ellin6070 in FO were significantly higher than those in the other treatments  and AK (VIF = 72.16) were removed because they strongly correlated with other physicochemical factors.db-RDA and linear regression analyses were used to analyze the effects of soil physicochemical factors and enzyme activities on the soil microbial community structure. Using the variance inflation factor (VIF) to judge the collinearity between different soil physicochemical factors, the physicochemical factors with VIF > 10 in soil physical and chemical indicators were screened and removed. NOr2 = 0.5745, p = 0.011), NH4+-N , TN , and TK  were significantly correlated with bacterial community structure. Further, pH , AP , and TK  were significantly correlated with fungal community structure.The selected physicochemical factors were compared with soil bacteria  and fungR2 = 0.5216, p = 0.008) and fungi . There was no significant correlation between urease, ACP, and catalase, and soil bacterial and fungal community structure.Linear regression analysis was used to evaluate the degree of explanation of the activity of sucrase, urease, ACP, and catalase to the variation in soil bacterial and fungal community structure . SucrasePlant-associated microbes are known to play important roles in plant health and disease . Roots aM. alpina YW25 and the rhizosphere microorganisms. The results showed that the mycelial growth of M. alpina YW25 was inhibited by some probiotics in the rhizosphere, such as Bacillus, Streptomyces, Brevibacterium, Trichoderma, and Penicillium (Cladosporium and Aspergillus (Bacillus and metabolites of Streptomyces (e.g. quercetin) may inhibit the growth of M. alpina YW25 mycelia on plates . These negative correlations between Mortierella and Fusarium have also been observed in other systems . This was the same as observed in previous studies  and Rhizobium were significantly enriched in MA (4+-N and NO3−-N) after M. alpina YW25 inoculation was significantly higher than that in FO. The AP content in the rhizosphere soil was positively correlated with the available nitrogen content , but negatively correlated with the available potassium content . The results showed that nitrogen and phosphorus availabilities were driven by each other between plants and soil  in ginseng roots were detected while exploring the reason for disease resistance , Sphingomonadaceae (Sphingomonas and Novosphingobium), and Rhizobium in MA_FO were significantly higher than those in FO . Inoculation of M. alpina in ginseng rhizosphere significantly alleviated the pathogenicity of F. oxysporum in ginseng plants, increased the content of available nitrogen and phosphorus in rhizosphere soil, and improved the activities of soil sucrase and ACP. M. alpina inoculation with F. oxysporum had the greatest effect on the microbial community in the ginseng roots and had a greater effect on the fungal community than on the bacterial community. M. alpina inoculation helped ginseng recruit more plant growth-promoting microorganisms, change the microbial structure of ginseng roots, and build a more stable microbial network of ginseng roots. Thus, it inhibited potential pathogens, effectively prevented the invasion of pathogens, and ensured healthy plant growth. Therefore, M. alpina helped Panax ginseng resist F. oxysporum infection by mainly regulating the fungal community in the root.To conclude, https://www.ncbi.nlm.nih.gov/, Biosample No. SAMN24474502.The datasets presented in this study can be found in online repositories. The names of the repository/repositories and accession number(s) can be found at: YW and HY conceived and designed the experiment. YW and LW performed the experiment. YW, LW, and MS analyzed the data. YW wrote the paper. HW, MZ, and HY guided the research work and thoroughly reviewed and corrected English language of the manuscript. All authors contributed to the article and approved the submitted version.This study was supported by Fundamental Research Funds for the Central Universities (No. 2572020DR08 and No. 2572020DP07).The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Moreover, the present structure attained satisfactory PERs of >20 dB and ILs of <0.5 dB within an ultrabroad BW of 200 nm.It is challenging to simultaneously consider device dimension, polarization extinction ratio (PER), insertion loss (IL), and operable bandwidth (BW) to design a polarization beam splitter (PBS) that is extensively used in photonic integrated circuits. The function of a PBS is to separate polarizations of light, doubling the transmission bandwidth in optical communication systems. In this work, we report a high-performance PBS comprising two-dimensional subwavelength grating metamaterials (2D SWGMs) between slot waveguides. The 2D SWGMs exhibited biaxial permittivity by tailoring the material anisotropy. The proposed PBS showed PERs of 26.8 and 26.4 dB for TE and TM modes, respectively, and ILs of ~0.25 dB for both modes, with an unprecedented small footprint of 1.35 μm × 2.75 μm working at the wavelength  Next, the resultant biaxially anisotropic emtε = diag  could be obtained according to Equations (2)–(4). With the obtained emtε in the region between slot waveguides and using COMSOL Multiphysics 6.0 , the coupling length of TM mode Lc,TM and the coupling-length ratio of TE and TM modes c,LTE/Lc,TM versus ts for the present PBS and the conventional SWs [c,LTE/Lc,TM implies that more TE power is retained in the bar while TM power is completely transferred to the cross. c,LTE was far larger than Lc,TM due to better TE mode confinement; thus, a PBS’s length is determined by a shorter Lc,TM. For conventional SWs [Lc,TM (dull blue dotted line) varied from 82.42 to 32.19 μm for ts for 10 and 60 nm, respectively, and c,LTE/Lc,TM (copper red dotted line) was only 9.16 at ts = 60 nm. In contrast, the proposed structure not only shrunk Lc,TM (dull blue solid line) to 10.69 and 3.15 μm for ts = 10 and 60 nm, respectively, but also improved c,LTE/Lc,TM (copper red solid line) to 891 at ts = 60 nm. Results demonstrate that the device length and PER of a PBS based on a two-SW can be significantly reduced and improved, respectively, by locating the proposed 2D SWGMs between the two SWs.First, we analyzed the mode characteristics of the present design. The relative permittivity of Si and SiO = 2.085 , respectonal SWs ,18 are sonal SWs , Lc,TM  and enhanced , respectively. In addition, the relative field amplitudes of the TE and TM modes along the line denoted in the inset of kTE that can be adjusted by the zzε/εxx ratio according to the dispersion relation [zzε > xxε condition is always fulfilled. Therefore, 2D SWGMs significantly reduce crosstalk compared to an isotropic cladding with zz/εxxε = 1. In contrast, the decay constant of the TM mode, kTM, depends on the zz/εyyε < 1 ratio, leading to weaker mode confinement.By adding 2D SWGs in the middle region of conventional SWs, the decaying rates of evanescent wave of the TE and TM modes are considerably suppressed ,bar(cro)( denotes the TE (TM) mode power at the bar (cross), and TEPTM),cro(bar)( is the TE (TM) mode power at the cross (bar). By adopting R = 3 μm and the same parameters displayed in y component of the magnetic field (yH) and total power (|P|) evolutions of TE mode are shown in y component of the electric field (yE) and total power (|P|) evolutions of TM mode are shown in Device performance dependences on geometry parameters, wavelength response, and fabrication tolerance proceeded by executing 3D simulations. To assess the transmission performance of a PBS, we analyze the PERs and ILs of both modes, which are formulated in Equations (7) and (8), respectively:Lc,TM at st = 60 nm was 3.15 μm on the basis of equivalent permittivity emtε. The practical Lc,TM to obtain optimal performance is device length LD = 2.75 μm, which was shorter than the calculated Lc,TM in LD = 2.75 μm, the obtained results were PERTE = 26.81 dB, PERTM = 26.48 dB, ILTE = 0.16 dB, and ILTM = 0.19 dB. By contrast, conventional SWs [Lc,TM = 34.6 μm achieved PERTE = 25.5 dB, PERTM = 14.8 dB, ILTE = 0.07 dB, and ILTM = 0.06 dB. Results show that the proposed PBS not only considerably reduced the proposed PBS’s length by about 12 times when compared to the conventional SWs [TM. Although the ILs of the current design were higher than those of the SWs, values of <0.2 dB were still acceptable. Considering the effect of duty cycles, we show the PERs and ILs versus xρ in xρ = 0.4 to 0.6. Once the condition of xρ > 0.6 had been reached, PERs and ILs dramatically degraded because a larger xρ decreases (increases) the value of zz/εxxε (zz/εyyε) leading to smaller (larger) kTE (kTM), simultaneously increasing the crosstalk of both modes. The higher PERs are also reflected in lower ILs. Although optimal PERs and ILs were at xρ = 0.4 or 0.5 here, the device length was LD = 6.50 or 4.15 μm, respectively. Considering compactness, we chose xρ = 0.6 to investigate the subsequent analyses, and PERs and ILs versus zρ are exhibited in In onal SWs  with Lc,onal SWs , but alszρ = 0.2 (LD = 2.9 μm) to 0.8 (LD = 2.55 μm), and PERTE and PERTM slightly varied as zρ varies. Differing from the major effect of xρ, zρ plays a finetuning role on device performance and length. Regarding to the number of Si strips (N), the PERs and ILs versus N (at the condition of xρ =0.6 and zρ = 0.6) are shown in N = 4 was chosen. Further increasing N resulted in moderately varying performance. The performance of TM mode dramatically worsened as N decreased. This result can be attributed to t xΛ being increasingly away from the condition of xΛ << λ, causing the increase in scattering loss that resulted from the grating structure [The ILs of the TE and TM modes slightly increased, ranging from tructure .TM (ILTM) significantly decreased (increased) as the wavelength moved away from the target wavelength of λ = 1550 nm because the short Lc,TM was more sensitive than the extremely long Lc,TE to deviation from the PMC. By contrast, the PERTE and ILTE of the shorter (longer) than λ = 1550 nm wavelengths were higher (lower) and lower (higher), respectively. This can be explained by the guided modes with shorter (longer) wavelengths leading to shorter (longer) evanescent wave tails, thus reducing (increasing) crosstalk between waveguides. The working BW of both modes with PERs > 20 dB and ILs < 0.5 dB ranged from λ = 1440 to 1650 nm (>200 nm).To assess the BW of the present PBS, the PERs and ILs as a function of wavelength are shown in To show our design’s superiority, we compared its overall performance with that of SWGM-based PBSs, as shown in ts and WCl to assess fabrication tolerance. Performance versus variations in Si strip width ΔWCl and slot thickness Δts is shown in TM significantly depended on the two fabrication errors (ΔWCl and Δts) because of the extremely short Lc,TM = 2.75 μm of the TM mode. As shown in TM decreased to ~17 dB (from ~26 dB), and ILTM increased to ~0.4 dB (from ~0.2 dB) while ΔWCl > 5 nm or Δts > 10 nm. Within the variation range of ΔWCl < 3 nm or Δts < 5 nm, PERTM maintained values of >20 dB and ILTM < 0.25 dB. In contrast, PERTE and ILTE showed slight variations in ΔWCl and Δts due to the exceptionally long Lc,TE = 891 μm of TE mode.In addition to analyzing performance dependence on duty cycles and number of Si strips, as shown in Wsw, as shown in TE (PERTM) and ILTE (ILTM) showed slight (significant) dependences on Wsw due to the extremely weak (strong) coupling strength induced by the 2D SWGMs. PERTM decreased to about 14.2 (9.8) dB, and ILTM increased to about 0.62 (1.25) dB, while Wsw increased to 5 (10) nm.Another essential fabrication error, angled sidewall, frequently occurs in etching processes that typically do not have a perfect 90° sidewall. In the present structure, the crucial parts are SWGMs due to their larger aspect ratio compared to that of the slot waveguides. Therefore, we now discuss the sidewall effect of the SWGMs on device performance. The width difference between the bottom and top of the SWGMs is TM maintained superior values of >20 dB and ILTM < 0.25 dB within the variation range of clad width ΔWCl < 3 nm or slot thickness Δts < 5 nm.An ultracompact and broadband PBS comprising slot waveguides assisted by in between 2D SWGMs was proposed to increase the integration density and transmission bandwidth of photonic devices. The proposed 2D SWGMs served as both a barrier to suppress TE mode coupling and bridging to improve TM mode coupling by carefully engineering the duty cycles of the SWGMs. The numerical results of the proposed PBS showed PERs of 26.8 and 26.4 dB for TE and TM modes, respectively, and ILs of ~0.25 dB for both modes, with a compact PBS of 1.35 μm × 2.75 μm. Moreover, the present PBS achieved satisfactory performance while operating in a BW of 200 nm. Fabrication tolerance analyses showed that the PER