Plant-based materials are an important source of bioactive compounds (BC) with interesting industrial applications. Therefore, adequate experimental strategies for maximizing their recovery yield are required. Among all procedures for extracting BC , the ultrasound-assisted extraction (UAE) highlighted as an advanced, cost-efficient, eco-friendly, and sustainable alternative for recovering BC  from plant sources with higher yields. However, the UAE efficiency is influenced by several factors, including operational variables and extraction process  that exert an impact on the molecular structures of targeted molecules, leading to variations in their biological properties. In this context, a diverse design of experiments (DOEs), including full or fractional factorial, Plackett–Burman, Box-Behnken, Central composite, Taguchi, Mixture, D-optimal, and Doehlert have been investigated alone and in combination to optimize the UAE of BC from plant-based materials, using the response surface methodology and mathematical models in a simple or multi-factorial/multi-response approach. The present review summarizes the advantages and limitations of the most common DOEs investigated to optimize the UAE of bioactive compounds from plant-based materials. Food losses and food waste are growing concern that significantly affects the environment and the sustainability of the food agroindustry. In developed nations, food loss occurs when supply exceeds demand. However, in less developed countries, the lack of infrastructure or adequate preservation and handling methods causes food losses to increase significantly each year, ranging from 30 to 60%. This fact, in turn, leads to environmental problems due to the generation of food waste and economic issues resulting from the waste of resources that could otherwise be used to improve food production and food security . In thisSecondary metabolites are compounds synthesized by plants through different metabolic pathways, such as shikimic acid, malonic acid, mevalonic acid, and non-mevalonate pathways. These compounds serve as signaling molecules or defense agents against predators, pests, and microorganisms, but they are not essential for the growth and development of plants ,8. The mBioactive compounds (BC) can be extracted from plant-based materials using various extraction methods ,12. TradThe application of UAE has emerged as an advanced, cost-efficient, eco-friendly, and sustainable alternative to conventional extraction methods for obtaining BC from plant sources with higher yields ,18,19. UThe present review summarizes the advantages and limitations of the most common Design of Experiments investigated to optimize the UAE of BC from plant-based materials.The solid-liquid extraction of BC from plant materials is often considered the initial and crucial unit operation when developing technological products or ingredients for various industrial purposes . There aPsidium cattleianum leaves using different conventional and non-conventional extraction technologies is presented in In order to solve the limitations of conventional extraction methods, non-conventional-assisted extraction techniques have been under investigation for the past 50 years . These eUAE is a green, efficient, low-cost, affordable, and user-friendly method for extracting BC from plant-based sources ,21. It iFicaria kochii flowers [Morus alba leaves [Hibiscus sabdariffa calyces [UAE can be applied directly using an ultrasonic probe or indirectly through an ultrasonic bath, depending on the configuration of the ultrasound devices. However, direct ultrasound application is generally more potent and efficient due to its concentrated effect in a specific area . On the  flowers , Morus aa leaves , peachesa leaves , green ta leaves , Hibiscu calyces , and ban calyces , among o calyces ,58,59.Several studies have highlighted the need for different UAE conditions for various plant-based matrices to maximize the extraction yield of the target compound ,21,31,40The design of experiments (DOEs) is a statistical methodology applied to support the design, development, and optimization of processes . DOEs enIn this context, these statistical tools are based on modeling complex relationships between factors and quantitative response variables in a univariate or multivariate approach to predict outcomes based on these relationships . The mosModeling has become a prevalent and effective tool in recent years for reducing the costs and time associated with conducting extensive experiments. Mathematical modeling enables the simulation, optimization, design, and control of processes . The appY = predicted response; X = independent variable; b1, b2, and b3 = regression coefficients for the linear effect term; b11, b22, and b33 = quadratic effect terms; b12, b13, and b23 = linear interaction effect terms [ct terms .Select the independent variables and their respective levels, along with potential response variables. At this stage, a screening design of experiments (DOE) can be employed.Choose the appropriate DOE.Conduct experiments and record the results.Develop a model equation based on the experimental data, which can be visualized as a contour plot or a 3D surface and Paret chart.Validate the model. This step often employs analysis of variance to identify the most significant factors in the model and assess their reliability.Determine the optimal conditions.Optimizing UAE using an RSM approach generally involves six key steps :Select tNephelium lappaceum husk [RSM, in general, is a predictive tool that analyzes the interactions between factors and responses, enabling process optimization with a reduced number of experiments . In thiseum husk , among oeum husk , fractioeum husk , Placketeum husk , Box-Beheum husk , centraleum husk , and othThe DOE is commonly used for optimizing processes, including UAE. However, when the optimization process involves multiple responses (more than one), it becomes impractical to optimize each response individually since the number of solutions equals the number of variables under investigation . In suchk, where k represents the number of factors) is the most used, followed by the three-level FFD. This approach is known for its robustness and adaptability and is particularly useful when there is suspicion of interactions between factors (iX and jX) [k < 5) to generate between 4 to 32 experimental runs. For instance, a full two-level factorial design for four factors would require 24 = 16 experiments. In general, the significance of the factors and their interactions is analyzed under the following model (Equation (2)):i-th level of factor A, i-th level of factor β, ij, Full factorial designs (FFD) involve the examination of all possible combinations of factors and levels that can be explored. This statistical tool provides a comprehensive understanding of process behavior. In FFD, all factors and their interactions are considered. There are various types of FFD, including those with two, three, and four levels, each offering different insights . The two and Xj) . Howevervariance .The FFD have been employed to assess the impact of several factors and their respective levels in UAE processes aimed at recovering BC from plant-based sources .3, RSM, and a quadratic model with R2 = 0.78), the interactions between time-solvent and temperature-solvent significantly influenced the extraction yield. Surprisingly, the interaction between temperature and time had no effect. The optimal UAE conditions for achieving the highest polyphenol extraction (67.87 mg/g) were 70% ethanol at 65 °C for 20 min [3 with 2 replications, RSM, and a quadratic model with R2 = 0.92). The optimal extraction conditions for maximizing the yield (13.23 mg/g) were 70% ethanol and a temperature of 54 °C for 60 min. However, the factors’ effects could be ranked as follows: ethanol concentration > extraction time > temperature [In factorial designs, factors and their respective levels are intentionally and simultaneously manipulated to assess their main effects on the variable response . In the r 20 min . Similarperature . It has perature ,96. Thesperature ,88. Howeperature . On the perature .3), it was observed that, in addition to extraction time and ethanol concentration, the extraction yield was significantly affected by the solid-to-liquid ratio, which is associated with the interaction between solute and solvent. The highest yield of phenolic compounds (487.67 mg/g) exhibiting strong antioxidant capacity (ABTS 92.50% and DPPH 73.73%) was achieved when using a mass-to-volume ratio of 1:7 with an ethanol/water mixture at 10% for 10 min [3, RSM, and quadratic models with R2 ranging from 0.77 to 0.98) from various mango by-products, such as peel , kernel , and endocarp , the best results were obtained when operating at the central experimental points, with a liquid-to-solvent ratio of 50%, amplitude of 60%, and an extraction time of 20 min. The most significant effects were attributed to the liquid-to-solid ratio and extraction time. In this context, the correct mixture of solvent and solid can expedite the release of BC from plant-based sources. Additionally, all extracts exhibited antioxidant properties, as demonstrated by DPPH tests [3, RSM, and a quadratic model with R2 of 0.93), where ultrasound power and the solid-to-liquid ratio significantly influenced the extraction yields [Furthermore, in the context of UAE for extracting polyphenols from rambutan husk  from malagueta peppers within a multi-response framework . FurtherBased on these data, FFD could serve as a powerful tool for optimizing the UAE process for the extraction of BC from plant-based materials ,102. Howkm−, where “m” represents the number of factors that have been removed in the fractional design to reduce the number of experiments [As mentioned earlier, the primary limitation of full factorial designs (FFD) is the substantial increase in the number of experiments as the number of factors increases (number of experiments = Levels × Factors). In this scenario, one alternative for reducing the number of experiments when dealing with an increasing number of factors in FFD is to employ fractional factorial designs . Generaleriments .The fractional factorial design has been explored to assess the impact of several factors and levels in UAE processes aimed at recovering BC from plant-based agro-industry foods .Pistacia lentiscus leaves . Lower ethanol concentrations led to higher yields since the addition of water to ethanol facilitated the extraction of phenolic compounds by breaking hydrogen bonds. However, these results were further fine-tuned using a Box-Behnken design and RSM [Annona glabra leaves, , temperature (5 °C) and solvent volume (25 mL) emerged as the most influential factors in terpene recovery, given their pesticidal activities. When it comes to the UAE of polyphenols, flavonoids, and anthocyanins from leaf extracts of Cecropia species , methanol concentration and extraction temperature played pivotal roles in the extraction of these three BC. Furthermore, these results were fine-tuned using a central composite design and RSM [Fractional factorial designs serve as valuable screening tools for subsequent optimization using other robust DOEs, particularly when extracting BC from plant-based materials . In this and RSM . Nonethe and RSM .5−1 fractional factorial design and Pareto chart). These extraction parameters were subsequently fine-tuned using a face-centered central composite design and RSM [5−1 fractional factorial design), with further optimization carried out using a CCD and RSM [Moringa peregrina , with optimization conducted using a central composite design and RSM [Furthermore, it has been reported that temperature, liquid-to-solid ratio, and ethanol concentration had a significant impact on the UAE of phenols, flavonoids, and anthocyanins from dried sour cherries in a preliminary screening experiment , serves as a useful tool for initiating the optimization process by screening a substantial number of factors  that may influence the response variable Y. It achieves this with a relatively low number of experimental runs [iβ having the highest absolute value corresponding to the most influential factor iX [The Plackett-Burman design (PBD) is a two-level factorial design (L12 and L32) developed by Plackett and Burman in 1946. It is designed for studying tal runs . One of tal runs ,73. In ttal runs . The impactor Xi . It is wactor Xi , as illuThe PBD has been employed to assess the impact of several factors and their levels in the UAE processes for recovering BC from plant-based sources .Lonicera caerulea using an L15 PPD, the most significant variables during the preliminary examination were found to be liquid-to-solid ratio, solvent concentration, and extraction time. Subsequently, Box- Behnken design and RSM were employed as robust tools for further optimization [During the initial optimization of UAE for flavonoids from hawthorn seeds, an L15 PBD ultrasonic time, ethanol concentration, and extraction temperature as the most influential variables. These variables were then chosen for further fine-tuning through Box-Behnken design and RSM . Similarmization .3-full factorial central composite face design [In the case of extracting phenolic compounds with antioxidant properties from grape pomace (L11 PBD), the ethanol concentration and sample-to-solvent ratio had a significant impact on the extraction yield. Notably, the solid-to-liquid ratio had a less pronounced effect on the extraction yield than the ethanol concentration. This can be attributed to the influence of solution polarity due to the presence of water in the extraction solvent, which enhanced the release of water-soluble phytochemicals. These parameters were chosen for further optimization using a 2e design . Similare design .Kaempferia parviflora rhizomes, the most influential factors included ethanol concentration, solvent-to-solid ratio, and extraction time. These factors were subsequently chosen for further optimization using a Box–Behnken design and RSM [Porphyra haitanensis [Acer saccharum [Additionally, the ethanol concentration, extraction temperature, and pH emerged as the most key factors for the recovery of anthocyanin compounds, while ethanol concentration, liquid-to-solid ratio, extraction temperature, and pH played crucial roles in the extraction of phenolic compounds from Rubia sylvatica Nakai fruit (L12 PBD and Pareto chart). These compounds exhibited antioxidant capacity. The UAE process factors related to the phenolic yield were further selected for optimization using a Box- Behnken design and RSM . Further and RSM . Moreovetanensis  and Aceraccharum .According to these data, the Plackett-Burman design is a viable screening tool for assessing the effects of various variables during the UAE process. It enables the elimination of non-significant variables from the models. After the initial screening, the key factors can be selected for further optimization using a robust DOE.The Box-Behnken design (BBD) is an independent rotatory design that employs the midpoints of the edges and center points within the cubic design region. This approach helps in avoiding extreme experimental conditions and reduces the risk of obtaining misleading results . BBD is Y represents the predicted response, iX corresponds to the values of the studied factors, β0 is a constant, iβ stands for the main effect coefficients for each variable, ijβ represents the coefficients for interaction effects, and ε accounts for the residual error.In this equation, The BBD has been investigated to evaluate the effect of varied factors and levels during UAE processes for recovering BC from plant-based sources .Piper betle  in a multiple response approach (desirability function), the solid-to-liquid ratio positively influenced the extraction yield. The highest extraction yield was observed at a solid-to-liquid ratio of 1:20 g/mL, accompanied by noticeable antioxidant capacity as determined by DPPH. This effect was associated with a larger concentration gradient of ethanol, which facilitated the propagation of acoustic waves and cavitation. As a result, there was an increase in mass transfer within the system due to enhanced diffusivity [3 BBD, RSM, quadratic models, and desirability ranging from 0.94 to 0.97) significantly influenced the UAE yield recovery of phenolics and flavonoids from yellow (R2 = 0.95) and red (R2 = 0.97) tamarillo fruits [During the UAE of phenolic compounds from fusivity . Furthero fruits . In thisPsidium cattleianum leaves , higher yields were obtained at shorter times, specifically 2 min. Controlling the extraction time in this manner prevented phenolic degradation and preserved their antioxidant properties [3 BBD, RSM, and quadratic model R2 = 0.97), it was observed that all factors significantly influenced the extraction process, with pulse cycle duration having the most substantial effect. The pulse cycle’s duration was associated with an increase in microbubble formation, which enhanced cell damage and facilitated the higher release of phenols. These phenols exhibited good antioxidant properties in various in vitro tests, including DPPH, ABTS, and FRAP [Annona muricata by-products, such as pulp, peel, seeds, and columella. Each of these materials was studied using a BBD, RSM, and quadratic models, and the results showed R2 values of 0.92, 0.98, 0.97, and 0.91, respectively [6 BBD, RSM, and quadratic models R2 = 0.99).In the case of the UAE of phenolic compounds from operties . Conversand FRAP . It is wectively . Similarectively , who fouv/v ethanol with a liquid-to-solid ratio of 5 mL/g at 55 °C for 25 min is an effective method for increasing the extraction yield of BC from common century under UAE . However, it is important to note that all individual and interacting parameters significantly influenced the extraction process [6 BBD, RSM, Pareto chart, and quadratic models, with R2 values of 0.70 and 0.82, emphasizing the significance of solvent concentration in the extraction process [Additionally, it has been reported that using 30%  process .4 BBD, RSM, and quadratic model R2 = 0.84–0.90), the pulse cycle and amplitude were found to be significant factors. The optimal multi-response conditions to maximize the total phenolic and flavonoid contents, along with higher antioxidant capacities assessed by DPPH and FRAP, were determined as follows: 70% methanol, 80% ultrasound amplitude, 0.58 s pulse cycle, and 12.8 min of extraction time. Furthermore, BBD, when applied in a multiple response approach using the desirability function, has been effectively used to optimize preliminary results. These preliminary results were obtained from other DOEs such as simplex-centroid or two-level factorial design, and they affected the analytical response during the UAE of phenols and flavonoids from malagueta peppers [On the other hand, in pomegranate peels , it was  peppers .According to these data, it is evident that several factors can influence the efficiency of the UAE process. Therefore, BBD is a valuable experimental design that allows for the evaluation of factors and their interactions in a reduced number of experiments. Moreover, BBD can be effectively employed in conjunction with other DOEs.k full factorial design or 2kp− factional design, with the addition of axial and central points. This type of DOE can accommodate a full quadratic model [Y is the predicted response, iX and jX are the levels for the studied factors, β0 is a constant, iβ, iiβ, and ijβ are the main effect coefficients for each variable, and ijβ are the interaction effect coefficients.The central composite design (CCD) is one of the most widely used statistical tools in optimization. It offers great flexibility and can be constructed from a 2ic model , as demoThe CCD has been investigated to evaluate the effect of different factors and levels during UAE processes for recovering BC from plant-based sources .2 values ranging from 0.90 to 0.94 and desirability of 0.82), the extraction of bioactive phenolic and flavonoid compounds with antioxidant properties from spinach roots was investigated in a multiple response approach [2 values of 0.94 and a desirability function) in a multiple response approach. The highest extraction yield was achieved with a 60% ethanol concentration for 30 min at 59 °C. However, the impact of ethanol concentration on the response depended on the extraction time, with the solvent’s effect being negligible at shorter times [2 values ranging from 0.88 to 0.93). Ethanol concentration was identified as the most significant factor associated with the polarity of the extractable compounds. Similarly, the highest UAE yield of total phenolic compounds from wheatgrass seeds was achieved using a CCD with three independent variables at five levels, RSM, a quadratic model with an R2 of 0.99, and a desirability function. The optimal conditions included a 56% ethanol concentration, 28 min at 59 °C [According to the literature, the most common form of the CCD includes three independent variables with five levels. In the context of UAE  for extracting phenolic compounds from chestnut shells, it was found that temperature and extraction time significantly influenced the extraction yield. The highest antioxidant activities were observed when the process was conducted at 70 °C for 40 min. This suggests that, under these specific experimental conditions, a greater quantity of polyphenols with antioxidant properties are extracted. However, it is important to note that while increasing the temperature may lead to higher yields of polyphenols, it also carries the risk of compound degradation during the extraction process [Sideritis raeseri using UAE  was achieved at 65% ethanol concentration for 50 min at 63 °C, with a solid-to-liquid ratio of 1:40. It’s worth noting that the extraction temperature and the solid-to-liquid ratio had a significant impact on the recovery yield of compounds. Interestingly, no interactions between the factors were observed, and they did not influence the response [In the context of UAE  from agro-industrial acerola residue, a multiple response approach employing the desirability function revealed the optimal conditions for achieving the highest yield of BC. These conditions involved an ethanol concentration of 46.49%, an ethanol-residue ratio of 8.66 mg/L, and an extraction time of 49.30 min. Notably, increasing the ethanol-residue ratio facilitated the interaction between the solvent and solute, leading to enhanced bioactive compound recovery. Additionally, the extraction time played a crucial role in preserving the antioxidant properties of the extracted compounds [Compared to CCD, a central composite rotatable design (CCRD) maintains a consistent prediction variance at equally spaced locations from the design center. In the context of UAE  for extracting BC with antioxidant properties  Havil leaves [Similarly, it has been reported that the optimal conditions for UAE  to achieve the highest yield of BC, including phenolics and flavonoids with antioxidant properties, from eratures . In thism leaves , kiwi pem leaves , Myrtus pericarp , palm prpericarp , green ppericarp , and Mitl leaves , and garl leaves .Garcinia indica , the extraction yield was found to be influenced by experimental conditions for both BC  and their antioxidant activities . Notably, these extracts also exhibited anticancer activity against human breast cancer cells [Nephelium lappaceum L. fruit peel [Taraxacum officinale [The face-centered design is a type of CCD with an alpha value of 1, in which axial points are positioned at the center of each face in the factorial space. This DOE requires three levels for each element. The Central Composite Face-Centered Design (CCFCD) has been explored to optimize the UAE process for obtaining BC from plant-based materials. For instance, in the case of UAE for BC with antioxidant properties from er cells . Additiouit peel  and Taraficinale .2 > 0.80 and desirability score of 100%) successfully optimized the UAE of polyphenols from Ceratonia siliqua L. in a multiple response approach. The most critical factor influencing the recovery yield was the solid-to-liquid ratio [Additionally, a non-standard central composite design  or minimum experiments are needed to represent the system accurately [DOF is defined in Equation (6):n and Ni denote the number of experiments and parameter levels, respectively.Taguchi design (TD) is a unique and powerful screening tool for identifying the significant factors that affect the extraction, both in terms of quantity and quality, of BC from natural sources in multifactorial experiments with mixed levels . It is acurately . This miiY) “larger-the-better”,  and “nominal-the-better”,  which depend on the preferred mean square deviation (MSD). The MSD represents the average performance characteristic value for each experiment (Equations (7)–(9)). The distinct signal-to-noise ratios (η) for n experiments are shown in Equation (10):In the TD, the outcomes of experiments are transformed into a signal-to-noise (S/N) ratio and are represented in decibels (dB). Three various signal-to-noise ratios are available, including “smaller-the-better”, , where the liquid: solid ratio is the main factor influencing the UAE processes. Thus, a correct solvent-solid mixture can accelerate the release of BC from plant-based sources [Curcuma longa rhizomes [The application of TD facilitates the identification of the optimal quantity of experiments required to yield the most advantageous data for a given set of factors . During  sources . An L9 Trhizomes .Azadirachta indica, tit was found that the particle size significantly influenced the extraction yield, followed by temperature and time. In this context, a reduction in the size of particles typically increases the contact area between plant cell walls and ultrasound, enhancing the yield extraction of BC; moreover, this fact is improved by temperature, which increases the mass transfer [Clitoria ternatea petals were at 50 °C and 10:1 mL/g for 30 min [2 of 0.91, and desirability of 0.95); these factors were selected for further optimization using a BBD and RSM [In the context of UAE  of phenolic compounds from transfer . On the r 30 min . Additio and RSM .The TD is commonly regarded as superior to traditional factorial or fractional factorial designs due to its ability to extract more accurate information from a limited number of experimental runs . Accordiq components or ingredients, and each experimental treatment is based on a specific blend or mixture of these ingredients. If we represent these proportions as x1, x2, …, xq, the components’ participation must adhere to two specific constraints: (i) the proportions must be values between zero and one; (ii) the q proportions always add up to one, resulting in the levels of the components iX not being independent of each other [During the UAE of BC from plant-based materials, solvent viscosity, polarity, vapor pressure, and surface tension play a crucial role in the efficiency of the extraction procedure ; therefoch other ,134,135.q components is provided by Equation (12):E(y) is the expected value of the response variable.iβ represents the expected response in the pure mixture iX = 1, and at the same time, it is the height of the surface at the vertex iX = 1.Once the experimental results from a mixture design are available, it is essential to establish a statistical model to explore the impact of the components on the response variable. A first approach would be to fit a first-order model (Equation (11)). On the other hand, the quadratic model for q components is given in Equation (13):In general, the special cubic model for The SCD and Lattice-Simplex design (LSD) have been employed to define the best extraction solvent mixture for optimizing UAE of BC from plant-based sources, as shown in Physalis angulate throughout a simplex-centroid design . They reported that the highest polyphenol yield was obtained with a solvent mixture composed of 57% water, 35% ethanol, and 8% methanol with a time of 10 min and 15 mL of extractor volume. These results were associated with the low viscosity of the solvent mixture that significantly enhanced the cavitation process. Similar trends were reported during the UAE  of polyphenols and flavonoids from Moroccan Pimpinella anisum in a multiple response approach, where the best proportions of extractor solvent were 44% water, 22% ethanol, and 34% methanol [It is well-known that the polarity and viscosity of the solvent can influence the ultrasound-assisted extractability of BC from plant materials. Therefore, a mixture of extractor solvents is frequently used during the UAE process . In thismethanol .Taraxacum assemanii ; moreover, in this study, the interactive effect between ethanol and methanol negatively affected the recovery yield polyphenols, possibly by the polarity of bioactive compound of T. assemanii [Capsicum frutescens, the best mixture proportion of extractor solvent was 95% ethanol and 5% water [−1 HCl) at 50:50 significantly increased the UAE  of polyphenols from pineapple byproducts. These effects were associated with the membrane denaturation effect of HCl [Additionally, it has been reported that the ethanol-water (68:32) mixture is effective in increasing the UAE yield of polyphenols from ssemanii . On the 5% water . Ethanol5% water . Additiot of HCl .2 = 0.94, and desirability function) yield of polyphenols from Eugenia uniflora [By combining 46% water, 13% methanol, 18% ethanol, and 23% acetone, it is possible to increase the UAE  was 44% acetone and 56% methanol. The resulting mixture had an intermediate polarity that increased the solute-solvent interaction and improved the dissolution and extraction of carotenoids. Interesting, the ternary mixtures composed of ethanol/petroleum ether/methanol and acetone/petroleum ether/methanol exhibited antagonistic effects during the UAE of carotenoids  [The best combination of extractor solution for recovery of the maximum yield of carotenoids from cashew apple by UAE  . 2 = 0.98 and desirability of 0.93), the best proportions of solvents for UAE of carotenoids from Mauritia flexuosa were 75:25 acetone: ethanol, which exhibited a synergistic effect during the extraction process. On the other hand, mixtures of acetone/methanol and acetone/acetonitrile exhibited antagonistic effects. It is attributed to the non-polar compounds of M. flexuosa, and the mixture of acetone/methanol efficiently extracted the BC of this plant-based material [In a multiple response approach  is characterized by an orthogonal array (but not exclusively). It is recommended for performing screening and optimizing experiments. DOD can minimize the number of runs and the variance in the prediction of specified model coefficients and is compatible with the RSM ,141,142.2 = 0.95 and 0.93, respectively), it was found that the most important factor that influenced the extraction yield of polyphenols was the content of water in the solvent followed by the type of solvent used, where the higher extraction yield was performed after 30 min of extraction containing 40% water in acetone. These effects were associated with the polar aprotic and polar protic characteristics of extractor solvent, which is more efficient than the pure solvents or the mixture of two polar protic solvents [2 of 0.99, and desirability function) of phenolic compounds from grapefruit leaves, where the best UAE conditions include ethanol concentration of 10.80% at 30.37 °C for 58.52 min. In this study, the presence of higher content of water in the extractor solutions positively affect the recovering yield of polyphenols, associated with its polarity, dielectric constant, and viscosity that help the swelling increase of the cell, releasing BC [In the context of UAE of phenolic compounds and flavonoids from walnut male flowers using a DOD  were using 41.70% methanol at 75 °C for 51.8 min. In this study, the temperature and ultrasound waves combined with methanol facilitate the release of BC from the plant matrix; however, these conditions should be further optimized with a robust DOE to avoid their degradation during UAE [Furthermore, it has been reported that the optimal conditions for extracting phenolic compound from ring UAE . Cynarascolymus leaves , the best conditions for obtaining a maximum yield of BC from this plant material were 20.05 min of extraction time and 65.02% of ultrasound amplitude, where the ultrasound amplitude was the most important variable [2 = 0.95). Additionally, DOD has been used to optimize the AUE of oleuropin from mango peels (desirability of 0.79–0.89) [In the case of the UAE of phenolic and flavonoid compounds from variable . Moreovevariable  during t79–0.89) .According to these data, DOD can maximize the determinant of the information matrix, requires a reduced number of runs, and is compatible with RSM. This DOE is typically used to identify the main factors involved in the UAE of BC from plant-based materials.David H. Doehlert created the Doehlert design matrix (DD). It is also known as the Uniform shell design. DD is derived from a spherical domain with an orthogonal array and is a not-rotatable DOE . This deCroton heliotropiifolius Kunth leaves (DD and Pareto chart), the higher yield was obtained at experimental conditions of 11.4 mL of 37.5% v/v ethanol at a temperature of 54.8 °C for 39.5 min [Physalis angulate L. by Moreira et al. [In the case of the UAE of phenolic compounds from 39.5 min . Additioa et al. , who infa et al. . The DD is typically used for optimizing several analytical procedures and has recently been explored to optimize the UAE process for obtaining BC from plant materials ,147.DOEs are typically investigated to optimize processes, including the UAE of BC from plant-based materials . AlthougHow many independent variables (factors) and levels per variable are there?How many experimental runs will be there?Is it a screening or an optimizing experiment?As mentioned before, the efficiency of the UAE depends on many factors. Therefore, selecting an appropriate DOE is required. In general, the statistical procedures depend on the research aims; nonetheless, experimenters should pose some questions before deciding on a DOE such as the following: A proposed diagram based on the information discussed throughout this work is shown in Additionally, it is important to note that each DOE exhibits its advantages and limitations, as shown in Ultrasound-assisted extraction is a green technology with competitive advantages to recover bioactive compounds from plant-based sources with higher yields than conventional extraction methods. However, the parameters involved in the UAE process influence its efficiency in the recovery yield of target compounds and their bioactivities. Thus, optimizing UAE conditions is necessary to achieve higher quality and yield bioactive compounds since the extraction conditions are dependent on the characteristics of each plant-based matrix.Design of experiments (DOEs) plays an essential role during the ultrasound-assisted extraction of bioactive compounds from plant-based sources. It permits the identification of the kay variables or factors involved in the extraction process, which facilitates the optimization of UAE in a single or multi-response approach. The main DOEs investigated for screening and optimizing UAE processes are Full factorial, Fractional factorial, Plackett–Burman, Box-Behnken, Central composite, Taguchi, Simplex-centroid and Lattice-simplex, D-optimal, and Doehlert. Most of these statistical designs are optimized using response surface methodology and polynomial equations that permit the prediction and validation of response variables.For its part, Derringer’s desirability function is a viable option when several response variables should be simultaneously optimized. Additionally, the UAE of bioactive compounds from plant-based materials could be performed in a combined DOE performance, one of them focused on the screening step and the other one on optimizing.In this context, during the optimal DOE selection, the physical limitations of experiments  must be considered. The selected DOE should be a secure image of interactions with the minimum amount of resources possible during the conduction of experiments. Therefore, this document provides a general overview of the most used DOE  for UAE of bioactive compounds from plant-based sources and how the optimal DOE can be selected depending on the research aim. However, further studies are needed to standardize the extraction conditions independently of the plant-based matrix that permits narrowing the gap between research laboratories and industry scale-up of UAE of BC from plant-based materials.


High loads of Enterobacteriaceae in the meat mixture of batch 2 and TBC in batch 5 were associated with a higher occurrence of bacterial pathogens. During ripening, water activity (aw) and pH failed to reach values lower than 0.86 and 5.3, respectively. Six Staphylococcus aureus and four Listeria monocytogenes isolates were collected from the salami meat mixture during ripening and the processing environment. A total of 126 isolates of Enterobacteriaceae were characterized at a species level, with Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, and Citrobacter freundii isolated from the final products. Results suggest the relevance of first steps of production in terms of the hygiene of raw materials and handling during stuffing procedures, especially when the physicochemical parameters of the final products do not reach values that represent hurdles for foodborne pathogens.Artisanal salami is produced in small-scale production plants, where the lack of full automation might result in higher variability in food intrinsic properties. The aim of the present study was to evaluate the inter- and intra-batch variability in physicochemical parameters and its impact on microbial quality and occurrence of foodborne pathogens on 480 samples collected from six batches of an artisanal Italian production of organic salami. Relatively high total bacterial counts (TBC) were found on the surface of the table in the stuffing room (4.29 ± 0.40 log cfu/cm An increased demand for artisanal foods has been observed in the last decades. These products are generally elaborated locally in small-scale, family-based companies perceived as producing healthier and more ethical food ,2. Due tItalian salami falls within the category of dry fermented sausages with a ripening period longer than 4 weeks and a water activity lower than 0.90 . In ItalEscherichia coli (STEC) as well as Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus were isolated from fermented productions [L. monocytogenes was detected in a French plant producing dry sausages, its equipment, and in 10% of the final products [Salmonella was detected in Italy in three dry fermenting processing plants with a prevalence of 16.7% in food and 5.8% in the environment [S. aureus was detected in raw meat, casing, semifinished, and finished fermented sausages produced in both a nitrite and a nitrite-free production in Spain [E. coli O157:H7, O103:H25, and O26:H11 have been identified as etiologic agents in outbreaks involving fermented pork and beef meat salami as vehicles in United States in 1994, in Sweden in 2002, in Italy in 2004, in Norway in 2008, and in Denmark in 2018 [Salmonella spp. were associated with outbreaks in Germany in 2001, Spain in 2011, and more recently in the United States in 2022, linked to salami sticks [Shiga toxin-producing ductions ,9,10. L.products . Higher products ,13,14,15 in 2018 ,18,19,20i sticks ,22,23. The aim of the present study was to evaluate the variability in physicochemical parameters and its impact on the microbiological quality and occurrence of foodborne pathogens in an Italian artisanal factory producing an organic pig-meat salami over a year of sampling. Based on results, potential routes of contamination are suggested. n = 30), salami from the drying room (n = 30), salami in the maturation room (n = 30), and salami after 10 (n = 30), 18 (n = 30), and 28 (n = 30) weeks of ripening in the storage room. Swabs from the surface of a table in the stuffing room (n = 30) as well as the walls (n = 90) and drains (n = 90) were also collected from the stuffing, drying, and maturation rooms. In addition, swabs from the stuffing machine (n = 30) were gathered. For environmental samples, sterile cotton swabs  were moistened in 10 mL of saline solution (0.9% NaCl) and then used to swab a 100 cm2 area. These samples were collected before disinfection and cleaning. Five sample units per matrix (food and environment) per batch were tested. Overall, six batches were analyzed: batch 1 (stuffing on the 1 July 2020), batch 2 (23 September 2020), batch 3 (7 October 2020), batch 4 (21 October 2020), batch 5 (4 November 2020), and batch 6 (18 November 2020).One artisanal Italian factory was sampled over 10 months (July 2020–May 2021). The factory produces an organic salami made of pig meat with no addition of nitrites/nitrates or starter cultures and with a ripening period of 6 months. Regarding processing, after the stuffing of a mixture of meat, spices, and salt into natural casing, salami were dried at 10 °C and RH 55–60% for 7–9 days and then stored in controlled environment for 5 weeks at 10 °C and RH 70% for maturation. Afterwards, salami were stored in a cellar up to 6 months . Raw matL. monocytogenes (ISO 11290-1), coagulase positive Staphylococci (ISO 6888-1), verotoxigenic E. coli (VTEC) (ISO 16649), and Salmonella (ISO 6579) were investigated in all 480 samples [E. coli on Tryptone Bile X-GLUC Agar , a PCR for the identification of Shiga toxin-encoding genes was applied as previously described [Enterobacteriaceae (ISO 21528-2) were enumerated in raw materials and semifinished and finished products [Enterobacteriaceae at a species level, 25 g of food sample was diluted in 225 mL of Buffer Peptone Water  and incubated for 24 h at 37 °C. BPW pre-enriched cultures were then streaked on MacConkey agar (Thermo Scientific) and incubated for 24 h at 37 °C. Five colonies per plate (both lactose fermenting and non-lactose fermenting) were submitted to biochemical test  and PCR for confirmation [Total bacterial count (TBC) ISO 4833-2), water activity (ISO 21807), pH ISO 2917), and the occurrence of  samples ,28,29,3017, and tescribed . Additioproducts ,33. More-2, waterirmation ,34,35,36p ≤ 0.05). To identify homogeneous groups, we applied Tukey’s HSD test. Additionally, we created boxplots to visually represent the variation in microbial counts within and between batches of salami samples stored at different temperatures throughout their shelf life.Data analysis and modeling were carried out using R Studio v4.2.2. Statistical comparisons were made between microbial counts from various food batches and environmental samples through ANOVA . These models were adjusted using the R packages lme4 [nlme to account for inter-batch variability, treating it as a random effect. Main effects considered the influence of the variables “Stage”  according to the form: Enterobacteriaceae), determined within the processing stage denoted as s, belonging to the batch labeled as b; β0 is the model intercept which can undergo random shifts denoted as bu, associated with the specific batch b; s; and i determined within the processing stage s, belonging to batch b. Samples, including environmental and drain swabs, meat mixture, and finished salami collected from each processing stage, were integrated into another main effects model as follows:i, which was obtained from the processing stage s within a specific batch b. The variability between batches within a factory was quantified by assessing the squared standard deviation of the random effects, while it was assumed that errors also conformed to a normal distribution.Longitudinal data sets, encompassing TBC and ges lme4  and nlme2 and 7.05 ± 0.61 log cfu/cm2, respectively. No statistically significant differences (p > 0.05) were observed for TBC between batches, also supported by the high intra-batch variability. Interestingly, the surface swab of the table in the stuffing room (STM) showed TBC 4.29 ± 0.40 log cfu/cm2 higher than those found in the other swabs of the same room, notably the stuffing machine swab  and the wall swab   .Enterobacteriaceae . In addition, significantly higher LAB counts were registered in samples of batch 2. Higher TBC counts in the meat mixture samples of batch 5 were observed compared to the other batches, except for batch 2 (p ≤ 0.05). Regarding the meat mixture used to produce salami, high intra- and inter-batch variability for the different groups evaluated was observed, especially for eriaceae . Higher Enterobacteriaceae load in all batches . In the final product of all batches, the load of Enterobacteriaceae was lower or close to the detection limit of 1 log cfu/g, suggesting that the ripening process was effective in reducing the risk for human health related to the potential occurrence of foodborne pathogens included in this bacterial family. Regarding salami samples, slight increases in TBC and LAB counts were associated with a decrease in  batches . Interes batch 1 . No statAs expected, the pH decreased along with the increase in LAB up to 3–10 weeks of ripening, after which it increased along with a reduction in LAB . InitialRegarding water activity, a constant decrease was observed from values ranging from 0.953 (batch 6) to 0.982 (batch 3) in the salami in the drying room to values ranging from 0.842 (batch 3) to 0.884 (batch 5) in salami after 28 weeks of ripening . Enterobacteriaceae counts throughout the salami production process. The outcomes of this investigation are presented in Generalized linear mixed models were created to explore whether variations in the production stage and the environment could account for some of the differences observed between batches in TBC and p ≤ 0.05). Specifically, the ripening step produced the largest increase (4.33 ± 0.27 log cfu/g), which can be partially attributed to the increase in LAB populations. During ripening, a positive effect was predicted for TBC counts in 18- and 28-week ripened salami  were similar to the TBC levels in the salami samples in the drying room , E. coli (30), Citrobacter freundii (26), Enterobacter cloacae (16), and Routella planticola (1)  . Enterobacter cloacae strain, six E. coli, two Citrobacter freundii, and two K. pneumoniae were found in the finished product, suggesting that although the ripening process was effective in reducing the risk associated with the presence of bacterial pathogens, it was not enough to guarantee the lack of bacterial pathogens in the final food product. Although the water activity in the final product was lower than 0.90, data on the increased pH suggest the need to better control this parameter, for example, by considering the possibility of shortening the ripening period from 28 to 18 weeks.Bacteria were collected from mixed meat and salami during and at the end of the ripening period, and environmental swabs were gathered during production. In particular, pathogens were mostly found in the meat mixture (22), the surface of the table in the stuffing room (15), and in the salami in the drying room (25) and after 3 weeks of ripening (19) . FollowiIn the present study, the effect of pH and water activity on the number of bacterial indicators of the process’s hygiene and the occurrence of foodborne pathogens was assessed in an artisanal Italian production of organic salami. S. aureus. The pH of the majority of Mediterranean-style fermented sausages is approximately 4.5/5.4, which has several beneficial effects on both the shelf life and the manufacturing process [pH is an essential parameter in fermented meat products. The acid hurdle is crucial for the control of the safety of the product ,39. pH v process . HoweverEnterobacteriaceae was lower than the detection limit in most final products, bacterial pathogens were detected. In the present study, the pH decreased below 5.3 after 10 weeks of ripening, after which an increase to values higher than 6 in the final products was achieved. These results might be associated with the lack of standardized starter cultures and the different growth rates of autochthonous LAB groups in each batch. In salami prepared with starter cultures of dairy origin, pH 5.3 was reached after 3 weeks of ripening . NeutralS. aureus control. Although not found in the final product, S. aureus was found in raw materials, salami in the drying room, and salami after 3 weeks of ripening. This finding suggests the relevance of a high microbiological quality of raw materials, especially when pH and water activity hurdles cannot be fully maintained. Water activity values lower than 0.90 and 0.86 are essential to control the growth of Gram-positive and Gram-negative bacterial pathogens, respectively ,42. In tBesides bacterial pathogens being found in the final product, the detection of pathogens in the processing environment is of concern since potential events of cross-contamination might occur involving both workers and the food product before commercialization. L. monocytogenes to survive on several environmental stress conditions boost the likelihood of detecting this foodborne pathogen in contaminated ready-to-eat products of meat, fish, and dairy-origin products [L. monocytogenes outbreaks were associated with ready-to-eat meat product contamination from Italy and worldwide [L. monocytogenes not being detected in the final products, it was found in the processing environment of batch 2 (manhole of the drying room). Therefore, a more intensive control of the contamination routes in the salami processing plant might be necessary. Likewise, S. aureus is able to tolerate a wide range of environmental conditions, including pH ranges from 4.5 to 9.0 and NaCl concentrations up to 9%. Many strains have been recently recovered from dry-cured meat processing facilities and related products [S. aureus strains from all batches but the first one, as well as from different sources , suggests that different strains have been introduced in the food processing chain through raw materials, hygiene failures, or food handlers. The ability of products ,44. Receorldwide ,46,47, aorldwide . Despiteproducts ,50. The Enterobacteriaceae represented the predominant family recovered across the salami facility, resulting in 6 species and 106 strains confirmed overall . Among Enterobacteriaceae, E. coli corresponded to the dominant species, exhibiting a remarkable predominance in the meat mixture and associated environment up to the drying and ripening of the product. Moreover, it represented the bacterial species isolated in the highest proportion from the final product (n = 6 strains). Additionally, K. oxytoca and K. pneumoniae as well as C. freundii and E. cloacae were recovered from five to six batches; these were associated with the environment and food matrices of the meat mixture and the drying room, then persisting in the salami throughout the ripening up to the final products, where few strains were detected. Though strains belonging to enterohaemorrhagic E. coli (EHEC) have been attributed to foodborne outbreaks associated with fermented sausage consumption [Escherichia spp. strains has been already pointed out in spontaneously fermented sausages of the Mediterranean area [Klebsiella spp. were detected from minced pork meat during fermentation and raw pork sausages before ripening in Belgium and Spain [E. cloacae and Citrobacter spp. during the ripening of traditional fermented sausages [sumption , the perean area . Correspnd Spain ,54, as wsausages ,55. Conssausages ,57,58, fWhether introduced from raw materials or environmental contamination due to poor hygienic conditions, enhanced hurdle technologies, disinfection measures, and training should be properly adopted to control the growth of potentially pathogenic or undesirable bacteria along the whole food chain. In the present study, the meat mixture and the surface of the table in the stuffing room were spotted as principal potential sources of contamination. The meat mixture might have been contaminated at the first steps of the production during the cutting and addition of spices, or before that, during the primary production. Unfortunately, no samples from pig carcasses were collected; therefore, no speculations can be formulated about carcass hygiene. However, since the same person owns both the primary production of the organic pig and the food production of organic salami, cross-contamination cannot be ruled out. The adoption of tailor-made biosecurity plans including the hygiene of farms and workers has been described as an effective measure to reduce the risk of occurrence of foodborne pathogens in pig farms and the dissemination of those bacteria to humans through direct contact . In addiHigh inter-batch variability was detected in the physicochemical and microbiological parameters of organic salami produced in an artisanal factory, confirming process standardization to be a challenge in small-scale, not fully automized, production facilities. Higher TBC in the meat mixture and on the surface of the table in the stuffing room were associated with a higher occurrence of bacterial pathogens, suggesting TBC to be a good predictor of the microbial quality of the final product. This predictor might be of particular relevance, especially when the protocol of production cannot guarantee the acid and desiccation hurdles essential for biohazard control. In these conditions, enhanced hygiene measures and training could be effective control measures against the growth of potentially pathogenic or undesirable bacteria along the whole food chain.


Ischemic heart disease (IHD) is a major global health concern, and its burden among young adults aged 25–49 years remains underexplored. This study aims to provide a comprehensive assessment of the global burden and trends of IHD over the past 30 years (1990–2019) among this age group, as well as to analyze the health inequalities related to socioeconomic development.Data from Global Burden of Disease Study 2019 (GBD 2019) were utilized to analyze the prevalence, mortality, and disability-adjusted life years (DALYs) rate of IHD among young adults globally. Joinpoint regression analysis was applied to examine the trends over the study period. Health inequality analysis was performed to investigate the disparities in IHD burden related to the Socio-Demographic Index (SDI) of countries.According to GBD 2019 data, in 2019, the global numbers of young adults with IHD cases, deaths, and DALYs were 18,050,671 , 597,137 , and 28,692,968 , respectively, accounting for 9.15%, 6.53%, and 15.7% of the total global cases. Over the past 30 years, the mortality  and DALYs rate  of IHD among young adults decreased, while the prevalence rate  and YLDs rate  increased. Furthermore, countries with lower levels of socio-demographic index (SDI) disproportionately bore a higher burden of IHD among young adults. The inequality slope index for young adult IHD shifted from −56.6 [95% CI (−480.4–370.2)] in 1990 to −583.0 [95% CI (−996.8 to −169.2)] in 2019, and the concentration index moved from −8.2 [95% CI (−8.5 to −7.9)] in 1990 to −13.2 [95% CI (−13.9 to −12.4)] in 2019.While the mortality and DALYs rate of IHD among global young adults have decreased over the past 30 years, the degree of inequality related to SDI among countries has continued to increase. Decision-makers in various countries should allocate resources wisely and implement effective strategies to improve the burden of young adults IHD globally and address the health inequalities associated with it. Since 1990, the total number of disability-adjusted life years (DALYs) and deaths from IHD has steadily increased, making it the leading cause of global deaths by 2019, with over 180 million DALYs and 9 million deaths . As a continuous quality improvement process, IHME updates each GBD study annually by incorporating all known advances in data, modeling, estimation methods, and health knowledge to reestimate the entire time series, ensuring that each GBD study includes the latest estimates. This study is based on the data obtained from the GBD 2019, which includes the annual comprehensive assessment of 369 diseases, injuries, and disabilities and 87 risk factors from 204 countries and territories worldwide from 1990 to 2019 . This study did not involve individual subjects.The GBD research used established data and was reviewed and approved by the Institutional Review Board of the University of Washington with a waiver of informed consent. All information regarding ethical standards can be obtained from the official website  (p < 0.05). The most significant increase occurred between 1992 and 2001 , and there was stability in the most recent seven years (from 2012 to 2019). In contrast, over the past 30 years, the mortality of IHD per 100,000 population among the 25–49 age group decreased from 24.5 to 22.0 . The most significant decrease occurred between 2010 and 2019 , while there was an increase from 1990 to 1995 . Similarly, in terms of DALYs, the DALYs rate per 100,000 population of IHD cases among the 25–49 age group decreased overall from 1,182.9 to 1,056.7 . The most significant decrease occurred between 2012 and 2015 , with stability between 2015 and 2019. However, the YLDs rate of IHD among young people showed a different trend. As shown in p < 0.05) from 1990 through 2019. The most significant increase occurred between 1990 and 2004 , and a decreasing trend was observed between 2014 and 2019 .Over the past 30 years, there have been overall increases in the prevalence, mortality, DALYs, and YLDs rate of IHD among the global population of all age groups, with AAPC values of 1.2%, 0.4%, 0.1%, and 1.2%, respectively ( < 0.05) . However3.3.In the 204 countries and territories worldwide, significant absolute and relative inequalities related to SDI were observed in the burden of IHD among young adults. Countries with lower SDI levels bore a disproportionately higher burden. As shown in 3.In this study, we utilized the global data from GBD 2019 to provide a comprehensive assessment of the burden of IHD among young adults aged 25–49 globally and its trends over the past 30 years. It has been well-established that the consequences of premature IHD are devastating. It has been reported as the leading cause of death and premature death in various populations across different states in the United States . India aThe long-term impact of IHD on survivors can lead to economic hardships and functional impairments, causing devastating consequences for young patients and their families . CurrentQuantifying the inequalities in the burden of IHD among young adults related to SDI can shed light on the distribution patterns of disease burden based on the level of socioeconomic development. The Prospective Urban Rural Epidemiologic (PURE) study indicates that major cardiovascular events are more common in lower-income countries and populations with lower education levels . CompareTo the best of our knowledge, this study represents the latest and most comprehensive analysis of the global burden of IHD among young adults aged 25–49 years over the past 30 years (1990–2019). The main strengths of this study include its long-term observation, wide geographical coverage, and large dataset. Despite significant efforts to provide a comprehensive analysis, the study has some limitations. Firstly, cases in low-income countries in the GBD may be underestimated, as there are limitations in diagnosis or reporting in low-income countries due to their poor healthcare performance, which may lead to misdiagnosis, underdiagnosis, file losses, and so on. Secondly, our study heavily relies on secondary data, and the results based on GBD modeling may be subject to inaccuracies and incompleteness in real-world data sources. Additionally, race and genetic factors may play a role in the distribution of IHD among different regions and countries , 33. How5.In summary, our study provides a comprehensive assessment of the distribution of burden and its changing patterns of IHD among young adults aged 25–49 globally over the past 30 years. Although the deaths and DALYs burden of IHD among young adults has decreased over the past 30 years globally, we found that countries with lower levels of socioeconomic development have borne a disproportionately higher burden of IHD. The increasing degree of inequality related to socioeconomic development over time further emphasizes the importance of increased investment in cardiovascular health for young adults, especially in low-SDI countries. We hope that this study will provide detailed information for policymakers to allocate resources, implement effective measures, promote cooperation among countries, and improve the burden of IHD among young adults in low-income countries.


Objective: The primary aim of this study was to evaluate the effect of palliative surgery using posterior transpedicular approach (PTA) with posterior instrumentation on pain response and quality of life (QoL) in patients with metastatic thoracic and lumbar tumors.Methods: From 2018 to 2019, 39 patients with metastatic thoracic and/or lumbar tumors were prospectively enrolled to measure the reduction in pain and the changes in QoL after surgical decompression with posterior instrumentation via PTA. The patient group was composed of 27 men and 12 women with a mean age of 60 years . Pain response was measured using the visual analog scale (VAS) and neurologic status was evaluated using Frankel grades. QoL was assessed with use of the EORCT QLQ-BM22 questionnaire before surgery (baseline) and at 1-, 3-, 6-, and 12-month after surgery. The survival times of all the patients were also collected.Results: All patients showed either an improvement or a similar pain level after surgery, which the VAS score decreased from 7.10 ± 2.22 preoperatively to 3.10 ± 2.15 one month postoperatively (P<0.05). 19 patients  showed neurological function improvement postoperatively. Among the 19 patients, 7 cases improved from Frankel grade C to D, 5 cases from grade C to E, and 7 cases from grade D to E. Another 20 patients still have the same Frankel grade postoperatively, however, most of them improved clinically. The QoL improvement of the patients was also evident after treatment. Paired-samples T-test examination of the postoperative scores showed a significant improvement in terms of pain location, pain severity and performance status (P<0.01). Compared with the preoperative score, the 1-month postoperative score of functional interference was significantly improved . There were no significant changes in social or psychological functioning. Three patients experienced cerebrospinal fluid leakage postoperatively, and they were all successfully managed by lying flat without a pillow. One patient experienced rod breakage, at 10 months after surgery. All the patients were alive at 3 months; however, 7 patients died within 3 to 6 months, and another 9 patients died from the disease within 6 to 12 months.Conclusions: The present feasibility study found that the application of the PTA for decompression and fusion in patients with spinal metastases is beneficial for achieving prompt and sustained pain relief, reducing neurologic deficits and improving functional outcomes, health utilities, and HRQoL. The spine is the most common boney location for cancer metastases Overall, those with metastatic spinal tumors are usually older, and have diminished pulmonary function and general state. Consequently, the anterior approach is not recommended for these patientsThis prospective clinical study was approved by the Ethical Review Committee of Peking University People's Hospital (No. 2020PHB149-01). Patients were prospectively enrolled from January 2018 to December 2019. The inclusion criteria were as follows: (i) patients who were over 18 years with a sober consciousness and has the ability to understand and fill in the questionnaires; (ii) patients with thoracolumbar vertebral metastases suffered severe pain, pathologic fractures and metastatic epidural spinal cord compression (MESCC). Patients with radio-resistant or previously radiated spinal lesions were also included in our study. Patients who could not tolerate operation or who had a predicted survival time less than 3 months were excluded. The predicted survival time of patients with spinal metastases was evaluated according to the revised Tokuhashi scoring systemThe European Organization for Research and Treatment of Cancer Quality of Life Questionnaire for Patients with Bone Metastases (EORTC QLQ-BM22) is used to assess disease symptoms related to bone metastasesGeneral anesthesia was performed in each patient. Then the patient was placed in the prone position, a midline incision was performed extending over the two lower and two upper vertebral over the lesion level. Exposure of posterior portions of the vertebra was made. Intraoperative C-arm visualization was used to detect the accurate vertebral level.Initially, transpedicular screws were placed into the two vertebrae upper and lower the damaged vertebra. A rongeur was used to remove the posterior spinous processes. Subsequently, laminectomy was performed by laminectomy rongeur. A temporary rod can be placed on one side after the removal of the posterior complex, which provides temporary stabilization against the instability caused by posterior complex decompression and protect nerve tissues from damage caused by unintended vibrations during manipulation.Bilateral laminectomy, facetectomy, and wide foraminotomy were performed on the lower and upper levels of the damaged vertebra. The intervertebral disc spaces of the damaged vertebra were emptied and 360 degree debridement was performed either directly via the tissue mass or via the spaces between the nerve roots with a transpedicular approach.After complete decompression of the neural structures and removal of the tumor, vertebral cement augmentation was performed to reconstruct the anterior column of the spine. Finally, the screws above and below the involved vertebral segment and the rod were fixed, and the system was stabilized posteriorly.The Chinese-language version of the EORTC QLQ-BM22 questionnaire was administered at baseline (before surgery) and at one, three, six, and twelve months postoperativelly. The patients received and returned the questions by a questionnaire software or paper version. Moreover, the Karnofsky performance score was used to present the general condition of patients. The visual analog scale (VAS) was used to evaluate pain, and Frankel grade was utilized to assess neurological function.P value < 0.05 was considered significant, and a power analysis was conducted.Statistical analyses were carried out by using SPSS software, version 22.0 . Normally distributed data were recorded using the means ± standard deviation (SD), while nonnormally distributed data were presented as the medians and range. Paired t-tests were used to compare the scores of each scale of the EORTC QLQ-BM22 at one, three, six, and twelve months with the baseline score. Preoperative and postoperative VAS scores were compared by using paired t-test. Kaplan-Meier curves were obtained, the date of surgery was the starting date, and death or the last known contact date was the censor date. A There were 27 male and 12 female with an average age at the time of surgery of 60 years . The most common origin of the primary tumor was the liver in 20.5%, followed by the lung, breast and kidney in 15.4% of cases each . The mean intraoperative blood loss was 1417 mL . No notable intraoperative complications were observed. Three patients experienced cerebrospinal fluid leakage postoperatively, and they were all successfully managed by lying flat without a pillow. One patient experienced rod breakage at 10 months after surgery who received a revison surgery.P<0.05). As shown in Figure All patients showed either an improvement or a similar pain level after surgery Table . The VASP<0.01). The painful sites scores were 14.5 , 13.5 , 11.9  and 11.0  at the 1-, 3-, 6-, and 12-months after surgery, respectively. Additionally, painful characteristics were more pronounced in this group of patients, which were 26.5, 25.6, 18.1 and 16.4 at 1-, 3-, 6-, and 12-months after treatment, respectively, compared to 53.0 preoperatively. With regard to functional interference, there was significant improvement one month postoperatively compared with the preoperative score . As shown in Table The QoL improvement of the patients was also evident after treatment. The EORTC QLQ-BM22 scores of the patients before treatment and 1-month 39 cases), 3-months (39 cases), 6-months (32 cases), and 12-months (23 cases) after treatment are shown in Table 9 cases, The mean follow-up was 15.9 months . All the patients were alive at 3 months; at 3 to 6 months 7 patients were dead, and at 6 to 12 months, another 9 patients died of disease. During follow-up, 29 patients died. The K-M survival estimate at 1 year postoperatively was 51.3%, and that at 2 years was 30.2% , and a combined approach. Because tumor location, the type of reconstruction needed, patient comorbidities, the extent of primary tumor, and the surgeon's preference have a great impact on the surgical approach, it is essential that the best surgical approach from the patient's perspective be carefully considered before surgery. In the past, many published retrospective studies have shown that 360 degree decompression with a single PTA provides circumferential decompression and stabilization simultaneously, which is associated with less morbidity in systemically compromised patientsPatient-reported HRQoL outcome measures convey information that can be critical in clinical decision making. Among other HRQoL-measuring instruments, the EORTC QLQ-BM22 can effectively detect changes in QoL in diverse bone metastasis populations. This study shows that decompression with a single PTA improves pain, neurologic and functional status, and that EORTC QLQ-BM22 can measure health utilities and HRQoL for symptomatic patients. Compared with preoperative scores, postoperative EORTC QLQ-BM22 scores for painful sites, pain characteristics, and functional interference scale were significantly lower at the 1-month and 3-, 6-, and 12-month follow-ups. As investigators mention in several other studies, spinal surgery for MESCC is associated with rapid, substantial, and sustained pain reliefIn a previous study, researchers reported that the Eastern Cooperative Oncology Group (ECOG), the Short Form 36 Health Survey (SF-36), the VAS scale, and the assessment of ambulatory status and motor function effectively evaluated the factors that influence the health status of patients with spinal neoplastic disease. In a retrospective study, Chen et al. In this study, the psychosocial aspects in the EORTC QLQ-BM22 did not reach statistical significance after surgery; which is predominantly due to the small sample size. In addition, patients had different concerns. For example, some patients worried less about a potential loss of mobility, and more about economic factors. Some patients were more worried about becoming dependent on others. Moreover, patients with MESCC represent a frail population with few reserves to deal with additional physical or emotional stress. In future studies, more cases should be included so that each psychosocial items for each individual question can be analyzed to identify areas in which differences are particularly apparent.This study has several limitations. Although this is a prospective single center study, it is limited by its small sample size and lack of controls. Second, there is no stratification by pathological type due to the small sample of patients. Prospective clinical studies are necessary to further investigate the long-term treatment outcomes of surgery for spinal metastases.Nonetheless, the present feasibility study found that the application of the posterolateral transpedicular approach for decompression and fusion in patients with spinal metastases can also benefit patients with MESCC in that it achieves prompt and sustained pain relief, reduceds neurolofic deficits and improves functional outcomes, health utilities and HRQoL. Given the overall low incidence, clinical heterogeneity, and rapid development of more efficient medical therapies for the treatment of MESCC, we support current efforts to collect prospective longitudinal data on spine oncology patients.JFN: Designing the study, Collecting and analyzing the data, Preparing the manuscript.ZQZ: Designing the study, Collecting and analyzing the data, Preparing the manuscript.JCW: Collecting and analyzing the data, Preparing the manuscript.TQY: Designing the study, Analyzing the data, Preparing the manuscript, Supervision.WG: Collecting the data, Preparing the manuscript.RLY: Collecting the data, Preparing the manuscript.XDT: Collecting the data, Preparing the manuscript.