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During the anaerobic digestion (AD) of fruit and vegetable waste (FVW), excessive particle size reduction can lead to the overproduction and inhibition of methanogenic microorganisms. This paper presents an in-depth analysis through experimental assays, modeling, and response surface analysis of the effect of particle size on methane production. A simple model was proposed considering the inhibition of the growth of methanogenic microorganisms and surface-based hydrolysis kinetics. The model parameters were estimated using experimental data from batch systems fed with FVW of varying particle sizes (ranging from 1.8 to 1000 μm). Response surface methodology establishes a statistical model for estimating methane production based on particle size and concentration. Numerical and statistical analyses were conducted using Matlab R2024a and Minitab 24 software. A model with an R2 of 0.89 was obtained, which determined an optimal concentration of 8.2 k g · m − 3 and a particle size of 742.3 μ m , yielding a methane production of 303.3 m 3 · k g − 1   V S , similar to the experimentally obtained range of 300.95 to 316.7 m 3 · k g − 1   V S . [ABSTRACT FROM AUTHOR]

Abstract This study explores the utilization of eight readily available agricultural waste varieties in Nigeria—sugarcane bagasse, corn husk, corn cob, wheat husk, melina, acacia, mahogany, and ironwood sawdust—as potential sources of cellulose. Gravimetric analysis was employed to assess the cellulose content of these wastes, following which two selected wastes were combined based on their cellulose content and abundance to serve as the raw material for the extraction process. Response Surface Methodology, including Box-Behnken design, was applied to enhance control over variables, establish an optimal starting point, and determine the most favorable reaction conditions. The cellulose extracted under various conditions was comprehensively examined for content, structure, extent of crystallinity, and morphological properties. Characterization techniques such as X-ray Diffraction, Scanning Electron Microscopy, and Fourier Transform Infrared Spectroscopy were employed for detailed analysis. Compositional analysis revealed sugarcane bagasse and corn cob to possess the highest cellulose content, at 41 ± 0.41% and 40 ± 0.32% respectively, with FTIR analysis confirming relatively low C=C bond intensity in these samples. RSM optimization indicated a potential 46% isolated yield from a hybrid composition of sugarcane bagasse and corn cob at NaOH concentration of 2%, temperature of 45 °C, and 10 ml of 38% H2O2. However, FTIR analyses revealed the persistence of non-cellulosic materials in this sample. Further analysis demonstrated that cellulose isolated at NaOH concentration of 10%, temperature of 70 °C, and 20 ml of 38% H2O2 was of high purity, with a yield of 42%. Numerical optimization within this extraction condition range predicted a yield of 45.6% at NaOH concentration of 5%, temperature of 45 °C, and 20 ml of 38% H2O2. Model validation confirmed an actual yield of 43.9% at this condition, aligning closely with the predicted value. These findings underscore the significant potential of combinning and utilizing agricultural wastes as a valuable source of cellulose, paving the way for sustainable and resource-efficient practices in various industrial applications.

The aim of this work was to optimize the sintering process of Tm-doped calcium fluoride in order to maximize the thermoluminescent (TL) response and the optically stimulated luminescence response when stimulated by visible light in the infrared (IRSL) and blue (BSL) regions. The samples were prepared by liquid phase synthesis. X-ray diffraction confirmed the formation of the characteristic calcium fluoride phase. In order to optimize the sintering process, response surface methodology (RSM) was applied separately to the three luminescence responses (TL, IRSL, and BSL). The results showed that this technique is an invaluable tool for optimizing the sintering process and that it is possible to approximate a predictive mathematical model that can estimate the luminescent area as a function of sintering temperature and time. [ABSTRACT FROM AUTHOR]

In the present work, a green method improved by surface response methodology (SRM) has been used for the synthesis of zinc oxide nanoparticles (ZnONPs) from coffee husks extract, in which Santa Barbara‐15 (SBA‐15) mesoporous silica has been embedded. The composite formed has been drop coated on bare glassy carbon electrode and the resulting sensor (ZnONPs/SBA‐15/GCE) was used for the sensing of acetaminophen (ACT). Reaction factors such as pH, incubation time and precursor concentration were optimized during nanoparticles synthesis using SRM. The synthesized nanoparticles and the composite were characterized by ultraviolet‐visible spectrophotometry (UV‐Vis), Fourier transform infrared (FTIR) spectroscopy, powder X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X‐ray (EDX/EDX‐mapping) analysis, thermogravimetry analysis/differential thermogravimetry (TGA/DTG), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS), showing the good elaboration of ZnONPs/SBA‐15/GCE. After optimization of parameters susceptible to affect the detection limit of ACT, the calibration curve was plotted from 4 μM to 32 μM, showing good linear response with a detection limit of 0.11 μM. The developed sensor shows good sensitivity, reproducibility, repeatability and storage stability at room temperature and was successfully applied for the determination of ACT in pharmaceutical sample. [ABSTRACT FROM AUTHOR]

The development of a bimetallic Fenton-type catalyst with desirable activity and reusability remains a major challenge for the practical degradation of organic pollutants. Herein, we focused on modifying almond shell hydrochar with a Fe/Cu bimetal (Fe/Cu-HC) to develop a catalyst capable of activating H2O2 for degrading MO. The bimetallic Fe/Cu-HC catalyst was synthesized through hydrothermal carbonization and pyrolysis and characterized using SEM, FTIR, BET analysis, and XRD to confirm the presence and uniform dispersion of Cu and Fe co-doped species on HC. The impact of various factors, such as the solution pH (X1), organic pollutant concentration (X2) and catalyst mass (X3), on dye degradation efficiency via heterogeneous Fenton oxidation, was examined using the BBD model coupled with Surface response methodology (RSM). The Fe/Cu-HC catalyst showed superior performance in degrading MO dye compared to single-metal catalysts (Cu-HC, Fe-HC), due to the synergistic interaction between Fe and Cu species. To demonstrate the heterogeneous Fenton catalytic performance of the synthesized FeCu/HC, the results showed that 98.97 % of methyl orange was eliminated under optimal conditions: 100 mg. l-1 of methyl orange, a duration of 1 h, a catalyst mass of 1.65 g. l-1, a pH of 6, and a concentration of 4 mM H2O2. In addition, the Fe/Cu-HC catalyst showed excellent stability over multiple cycles, with minimal metal leaching. These results indicate that Fe/Cu-HC is a promising catalyst for the degradation of methyl orange and pave the way for the development of other cost-effective and efficient bimetallic catalysts for environmental remediation.

Bitter melon (Momordica charantia) is a rich source of phytochemicals including phenolic compounds with diverse health-promoting benefits and potential food industry application due to their antioxidant potential. Bitter melon leaves have been limitedly investigated in comparison to bitter melon fruits. The current work explores the use of green extraction methodology to optimize enhanced extraction of phenolic compounds from bitter melon leaves using ultrasonically assisted extraction and choline chloride-acetic acid (CHAC)–based natural deep eutectic solvent. Extraction using CHAC significantly improved the extraction of total phenolic compounds, total flavonoids, and individual phenolic compounds (including gallic acid, chlorogenic acid, vanillic acid, epicatechin, and quercetin-3-glucoside) in comparison to water, ethanol, and methanol. The effect of molar ratio, water content, temperature, and time on the extraction efficiency of bitter melon leaf phenolic compounds by CHAC was explored and optimized with surface response methodology (central composite design). The optimum condition for the extraction of individual phenolic compounds is a molar ratio of 1:4.35 CHAC with 20.68% water content at 75 °C for 21.23 min. Evaluation of the bioaccessibility of individual phenolic compounds concluded that the most bioaccessible compound was vanillic acid (105.00 ± 2.52%) followed by salicylic acid, chlorogenic acid, syringic acid, gallic acid, epicatechin, and quercetin-3-glucoside. [ABSTRACT FROM AUTHOR]

A fraction of rice bran (RB), generated during the brown rice polishing, is utilized to extract oil, resulting in defatted RB (DRB). The aim of this study was to optimize the emulsification conditions to enhance the value of this byproduct by formulating potential vegan dressings and characterizing them. Enzymatic hydrolysis of the starch present in DRB yields the DRB concentrate (DRBC). A central composite design was applied and the results were analyzed using response surface methodology to select optimal conditions for an oil‐in‐water emulsion formula. Two formulations were chosen: one corresponds to the optimal conditions, with 26.5% of oil and 73.5% of DRBC dispersion (eoptimal), and the other one with 21.7% of oil and 78.3% of dispersion (eED8). The eoptimal formulation exhibited significantly lower mean De Brouckere diameter (D4,3) value and higher viscosity when compared with eED8. For both emulsions, the particle size distribution and D4,3 remained unchanged during storage, whereas viscosity decreased, and backscattering (BS) increased. Initially, both emulsions exhibited solid viscoelastic behavior, which was partially lost during quiescent storage. The increase in BS was attributed to particle disaggregation, ultimately leading to the aforementioned change in rheological behavior. In conclusion, although the designed emulsions underwent microstructural changes, they were stable against gravitational separation. To improve stability during quiescent storage, it is suggested to incorporate a thickening agent. Hence, it is propose to procced with the development of a vegan dressing based on the eoptimal emulsion, as it exhibits superior physicochemical properties. [ABSTRACT FROM AUTHOR]

Abstract In the present work, a green method improved by surface response methodology (SRM) has been used for the synthesis of zinc oxide nanoparticles (ZnONPs) from coffee husks extract, in which Santa Barbara‐15 (SBA‐15) mesoporous silica has been embedded. The composite formed has been drop coated on bare glassy carbon electrode and the resulting sensor (ZnONPs/SBA‐15/GCE) was used for the sensing of acetaminophen (ACT). Reaction factors such as pH, incubation time and precursor concentration were optimized during nanoparticles synthesis using SRM. The synthesized nanoparticles and the composite were characterized by ultraviolet‐visible spectrophotometry (UV‐Vis), Fourier transform infrared (FTIR) spectroscopy, powder X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X‐ray (EDX/EDX‐mapping) analysis, thermogravimetry analysis/differential thermogravimetry (TGA/DTG), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS), showing the good elaboration of ZnONPs/SBA‐15/GCE. After optimization of parameters susceptible to affect the detection limit of ACT, the calibration curve was plotted from 4 μM to 32 μM, showing good linear response with a detection limit of 0.11 μM. The developed sensor shows good sensitivity, reproducibility, repeatability and storage stability at room temperature and was successfully applied for the determination of ACT in pharmaceutical sample.

During the anaerobic digestion (AD) of fruit and vegetable waste (FVW), excessive particle size reduction can lead to the overproduction and inhibition of methanogenic microorganisms. This paper presents an in-depth analysis through experimental assays, modeling, and response surface analysis of the effect of particle size on methane production. A simple model was proposed considering the inhibition of the growth of methanogenic microorganisms and surface-based hydrolysis kinetics. The model parameters were estimated using experimental data from batch systems fed with FVW of varying particle sizes (ranging from 1.8 to 1000 μm). Response surface methodology establishes a statistical model for estimating methane production based on particle size and concentration. Numerical and statistical analyses were conducted using Matlab R2024a and Minitab 24 software. A model with an R2 of 0.89 was obtained, which determined an optimal concentration of 8.2 kg·m−3 and a particle size of 742.3 μm, yielding a methane production of 303.3 m3·kg−1 VS, similar to the experimentally obtained range of 300.95 to 316.7 m3·kg−1 VS.

In this study, thermogravimetric (TG) curves of a synthetized renewable polyurethane–urea were modelled in intermediate heating rates from those experimentally tested. The response surface methodology (RSM) was used to optimize the tests by creating new TG curves. Flynn–Wall–Ozawa kinetic model was applied in the theoretical curves and re-applied in the new theoretical ones. The predicted curves showed similar curve format, but different kinetic results compared to the experimental ones (Ea = 170.56 kJ mol−1 and A = 4.11E10 s−1 for the experimental curves, and Ea = 84.71 kJ mol−1 and A = 0.02 s−1 for the predicted ones). Also, Pearson correlation coefficient was plotted in function of the heating rate, mass loss at 5%, the three peak temperatures and mass residue, showing that the mass loss has no significant influence on the other parameters tested. Considering the heating rates and the peak temperatures, the p values were 0.11, 0.078, and 0.056 for the Tp1, Tp2, and Tp3, respectively. This means that there are 89%, 92.2%, and 94.4% of chance that the results are not due to random chance. As main conclusion, the poorer correlation among the variables of the predicted curves using the Pearson correlation reflected in distinct Flynn–Wall–Ozawa parameters. [ABSTRACT FROM AUTHOR]

Clove essential oil is traditionally used as an anesthetic, analgesic, or insecticide, and recently, its applications as an antimicrobial, antioxidant, or anticancer agent have been explored. Nanoemulsions are thermodynamically unstable dispersions (d < 100 nm) produced by mixing two immiscible phases, which, in many cases, improve the stability and biological activities of functional ingredients for pharmaceutical, cosmetic, or food applications. This research optimized the formation of clove essential oil nanoemulsions by employing response surface methodology. The surfactant concentration was minimized by modifying the percentage of clove oil (0–100%), surfactant content (1–4%), and oil phase content (0–20%). In the optimum conditions, a nanoemulsion (93.19 ± 3.92 nm) was produced using 1.0% surfactant and 2.5% oil phase of which 50.7% was clove essential oil. The optimized nanoemulsion was stable in rapid stability tests (centrifugation, freezing–thawing, and heating–cooling), but its average droplet size increased during storage at different temperatures. The nanoemulsion contains a phenolic content equivalent to 736 mg gallic acid/mL. However, the antioxidant capacity of the essential oil (IC50 = 0.78 µg/mL) was dismissed in the nanoemulsion (IC50 = 2.43 µg/mL). The antimicrobial activity of the nanoemulsion showed strain–dependent behavior with MIC ranging from 0.0468 to 0.75 mg/mL, where E. coli and S. typhimurium were the most susceptible pathogenic bacteria. Finally, nanoencapsulation of clove oil showed higher in vitro cytotoxic activity against Caco–2 cancer cells (227 μg/mL) than free clove essential oil (283 μg/mL), but nanoemulsion (306 μg/mL) was less effective than oil (231 μg/mL) in the HT–29 line. This research shows the potential of clove essential oil nanoemulsions for developing biological therapies to treat diseases. [ABSTRACT FROM AUTHOR]

Caking remains a problem for the fertilizer industry in Thailand, especially for NPK fertilizers (15‐7‐18 and 18‐4‐5), leading to difficulty in application. In this work, we developed new water‐based anticaking agents to obtain high anticaking performance using response surface methodology (RSM) with Box–Behnken Design (BBD). Nineteen chemical substances were screened and effects of three independent variables (polymer, surfactant, and solvent contents) were investigated. The practicability of the model validated through analysis of variance (ANOVA) and experiments were compared. Anticaking performance of the coatings was validated using our designed‐accelerated caking method, expressed as the percentage of decrease in caking (%DC). Crushing strength and SEM/EDS analysis were used to evaluate the mechanical property and elemental composition of the coated fertilizers, respectively. The results suggested that different optimal compositions were required for different fertilizer formulas. In addition, only surfactant had a positive effect on caking prevention. The optimized anticaking coatings for 15‐7‐18 and 18‐4‐5 showed excellent performance with 92.0 %DC and 98.8 %DC, respectively. [ABSTRACT FROM AUTHOR]

Vegetal fibers can be applied in several areas, from the medical field to the development of new advanced materials. They have a complex chemical structure including cellulose, hemicellulose, and lignin. Each component plays a different role in the thermal degradation. Apart from it, this study aims to simulate and predict different ratios of cellulose/hemicellulose/lignin in the thermal degradation behavior of a vegetal fiber. This study was divided into two distinct parts: (i) firstly, the thermogravimetric curves (TG) were simulated based on their chemical composition to verify the influence of each component ratio in the degradation behavior. Briefly, 100% hemicellulose sample showed the lowest Tonset, 100% lignin sample showed the highest residue, and 100% cellulose sample showed the lowest residue at 600 °C among all samples studied. (ii) Secondly, a prediction of the thermal behavior for any combination of cellulose, hemicellulose, and lignin was performed by using an artificial neural network (ANN) combined with a surface response methodology (SRM). The prediction curves presented high reliability with the experimental fit, which allowed the thermal degradation behavior prediction of a vegetal fiber with any cellulose, hemicellulose, and lignin ratio. [ABSTRACT FROM AUTHOR]

Tobacco is a rich source of cellulosic material and one of the most cultivated non-food plants in the world with great potential for incorporation in polymeric matrices. The use of tobacco residues as reinforcing filler requires chemical/physical fiber treatment aiming to maximize compatibility with the polymer. In this study, tobacco residues were treated with two concentrations of NaOH (10 or 15 wt.%) at two-time exposures (3 or 5 h). Four distinct heating rates were used for each condition. It was applied an artificial neural network to model the thermogravimetric curves. After, the fitted ANN curves were used to create a 3D surface response. The equations from 3D surface response allowed the creation of thermogravimetric curves in any heating rate situated between the minimum and maximum range tested.

The ability to undergo from a deformed shape to its original shape when induced by an external stimulus brought many benefits in the polymer field. Despite the shape recovery, the structure vs property relationship has to be profoundly understood aiming to highlight the most important factors regarding the shape-memory polyurethanes (SMPUs). Based on a previous study, we show herein a complete description of the dynamic mechanical analysis for twelve different SMPUs. Also, it is presented an artificial neural network approach followed by a response surface methodology that allows modeling the dynamic mechanical curves with high reliability and low error. This principle expands the design versatility for SMP, which has broad implications in many other areas including soft robotics, flexible electronics, and medical devices. [ABSTRACT FROM AUTHOR]

This paper presents a multi-objective design optimization of a power transformer to find the optimal geometry of its core and the low- and high-voltage windings, representing the minimum power losses and the minimum core and copper weights. The optimal design is important because it allows manufacturers to build more efficient and economical transformers. The approach employs a manufacturer's design methodology, which is based on the usage of the laws of physics and leads to an analytical transformer model with the advantage of requiring a low amount of computing time. Afterward, the multi-objective design optimization is defined along with its constraints, and they are solved using the Non-Sorting Genetic Algorithm III (NSGA-III), which finds a set of optimal solutions. Once an optimal solution is selected from the Pareto front, it is necessary to fine-tune it with the 3D Finite Element Analysis (FEA). To avoid the large computing times needed to carry out the 3D Finite Element (FE) model simulations used in multi-objective design optimization, Response Surface Methodology (RSM) polynomial models are developed using 3D FE model transformer simulations. Finally, a second multi-objective design optimization is carried out using the developed RSM empirical models that represent the cost functions and is solved using the NSGA-III. The numerical results of the optimal core and windings geometries demonstrate the validity of the proposed design methodology based on the NSGA-III. The used global optimizer has the feature of solving optimization problems with many cost functions, but it has not been applied to the design of transformers. The results obtained in this paper demonstrate better performance and accuracy with respect to the commonly used NSGA-II. [ABSTRACT FROM AUTHOR]

Discharging livestock manure slurry without proper treatment causes various environmental and sociological problems. Chemical coagulation is a widely used and easily applicable method for treating such wastewater. However, the technique requires optimization to enhance coagulation efficiency while minimizing chemical usage. In this study, we propose an efficient, low-cost, and environmentally safe chemical coagulation method for solid–liquid separation of dairy manure slurry. Experiments were conducted in laboratory jar tests using dairy manure slurry to investigate the impact of coagulants, specifically polyaluminum chloride (PAC) and cationic polyacrylamide (CPAM), as well as pH, on the process of solid-liquid separation. Preliminary ranges of PAC, CPAM, and pH were estimated through single-factor experiments. Coagulation optimization and modeling were performed using the response surface methodology (RSM) with the Box-Behnken design (BBD), wherein the desired goal of each parameter was set to maximize solid–liquid separation efficiency while reducing chemical dosage to maintain residual aluminum (Al) concentrations below water quality standards. Numerical optimization predicted that the optimal dosages were 75 mg/L of PAC and 35 mg/L of CPAM at pH 7. Under these conditions, removal efficiencies of 99% for turbidity and 97% for chemical oxygen demand (COD) were achieved, with a minimal residual Al concentration of 0.045 mg/L. Positive zeta potential values in the treated water confirmed complete separation of negatively charged solids in the dairy manure slurry. The response values predicted by BBD aligned with the experimental results, and the analysis of variance (ANOVA) demonstrated the predictability and accuracy of the response models. Consequently, this study highlights the practical application of RSM with BBD in optimizing chemical coagulation using PAC and CPAM to achieve efficient solid–liquid separation in livestock wastewater while maintaining low residual Al concentrations.

Mesoporous silica has been synthesized with ricinoleic methyl ester (Ricinus communis) as a template. Fourier-transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), and N2 adsorption were used to characterize the adsorbent. The Response Surface Methodology (RSM) was used to optimize the adsorption of copper (II). As seen in the results, there was a good correlation between the values found in experiments and the values predicted by the quadratic model (P

A response surface methodology (RSM) was performed to study the influence of spot overlapping and pulse energy on back wall dross and surface roughness for fiber laser cutting of AISI 316 L stainless steel minitubes. Three treatments were compared to expel molten material (argon gas, compressed air, and a control test). Our results indicated that back wall dross and dross height reduction is observed when argon gas or compressed air is used through tubes compared with the control test. Additionally, a higher value of spot overlap (87.49%) and a lower value of pulse energy (30.31 mJ) resulted as the optimal parameters to cut minitubes.

Tobacco is a rich source of cellulosic material and one of the most cultivated non-food plants in the world with great potential for incorporation in polymeric matrices. The use of tobacco residues as reinforcing filler requires chemical/physical fiber treatment aiming to maximize compatibility with the polymer. In this study, tobacco residues were treated with two concentrations of NaOH (10 or 15 wt.%) at two-time exposures (3 or 5 h). Four distinct heating rates were used for each condition. It was applied an artificial neural network to model the thermogravimetric curves. After, the fitted ANN curves were used to create a 3D surface response. The equations from 3D surface response allowed the creation of thermogravimetric curves in any heating rate situated between the minimum and maximum range tested. [ABSTRACT FROM AUTHOR]

Closed die hot forging of 304L stainless steel is difficult compared to carbon and micro-alloyed steels in terms of higher forming force and defects. An appropriate combination of design and process factors including cross-section diameter, initial billet temperature, and flash land thickness is crucial to minimize the forming force without causing any under-filling or folding defects. This paper aims to develop an optimized closed-die hot forging process for long, thin, and tubular rail body components used in gasoline direct injection systems. The effects on the forging load are investigated using computer experiments containing the finite element method under a full factorial array of three factors at three levels to obtain the main and interaction effects. Linear and quadratic surface response analyses are performed to define the relation between forging load and input factors, and finally, the simulations are validated with some limited experiments. The simulation results that fit the nonlinear regression model were in close agreement with the experiments, and an optimal set of parameters is conveniently proposed for industrial production. [ABSTRACT FROM AUTHOR]

The development of a bimetallic Fenton-type catalyst with desirable activity and reusability remains a major challenge for the practical degradation of organic pollutants. Herein, we focused on modifying almond shell hydrochar with a Fe/Cu bimetal (Fe/Cu-HC) to develop a catalyst capable of activating H 2 O 2 for degrading MO. The bimetallic Fe/Cu-HC catalyst was synthesized through hydrothermal carbonization and pyrolysis and characterized using SEM, FTIR, BET analysis, and XRD to confirm the presence and uniform dispersion of Cu and Fe co-doped species on HC. The impact of various factors, such as the solution pH (X 1), organic pollutant concentration (X 2) and catalyst mass (X 3), on dye degradation efficiency via heterogeneous Fenton oxidation, was examined using the BBD model coupled with Surface response methodology (RSM). The Fe/Cu-HC catalyst showed superior performance in degrading MO dye compared to single-metal catalysts (Cu-HC, Fe-HC), due to the synergistic interaction between Fe and Cu species. To demonstrate the heterogeneous Fenton catalytic performance of the synthesized FeCu/HC, the results showed that 98.97 % of methyl orange was eliminated under optimal conditions: 100 mg. l-1 of methyl orange, a duration of 1 h, a catalyst mass of 1.65 g. l-1, a pH of 6, and a concentration of 4 mM H 2 O 2. In addition, the Fe/Cu-HC catalyst showed excellent stability over multiple cycles, with minimal metal leaching. These results indicate that Fe/Cu-HC is a promising catalyst for the degradation of methyl orange and pave the way for the development of other cost-effective and efficient bimetallic catalysts for environmental remediation. [ABSTRACT FROM AUTHOR]

Clove essential oil is traditionally used as an anesthetic, analgesic, or insecticide, and recently, its applications as an antimicrobial, antioxidant, or anticancer agent have been explored. Nanoemulsions are thermodynamically unstable dispersions (d < 100 nm) produced by mixing two immiscible phases, which, in many cases, improve the stability and biological activities of functional ingredients for pharmaceutical, cosmetic, or food applications. This research optimized the formation of clove essential oil nanoemulsions by employing response surface methodology. The surfactant concentration was minimized by modifying the percentage of clove oil (0–100%), surfactant content (1–4%), and oil phase content (0–20%). In the optimum conditions, a nanoemulsion (93.19 ± 3.92 nm) was produced using 1.0% surfactant and 2.5% oil phase of which 50.7% was clove essential oil. The optimized nanoemulsion was stable in rapid stability tests (centrifugation, freezing–thawing, and heating–cooling), but its average droplet size increased during storage at different temperatures. The nanoemulsion contains a phenolic content equivalent to 736 mg gallic acid/mL. However, the antioxidant capacity of the essential oil (IC50 = 0.78 µg/mL) was dismissed in the nanoemulsion (IC50 = 2.43 µg/mL). The antimicrobial activity of the nanoemulsion showed strain–dependent behavior with MIC ranging from 0.0468 to 0.75 mg/mL, where E. coli and S. typhimurium were the most susceptible pathogenic bacteria. Finally, nanoencapsulation of clove oil showed higher in vitro cytotoxic activity against Caco–2 cancer cells (227 μg/mL) than free clove essential oil (283 μg/mL), but nanoemulsion (306 μg/mL) was less effective than oil (231 μg/mL) in the HT–29 line. This research shows the potential of clove essential oil nanoemulsions for developing biological therapies to treat diseases.

Inadequate global fossil fuel reserves have forced researchers to investigate alternative fuel sources, and oleaginous microorganisms have attracted attention with their potential. Since high lipid production yield is an important criterion for suitable fuel production, in this study an oleaginous yeast, Yarrowia lipolytica, was selected and the lipid and biomass productivity under molasses (M20) substrate and nutrient supplementation was investigated. The effect of phosphorus as dipotassium hydrogen phosphate (K2HPO4), magnesium as magnesium sulphate (MgSO4), and yeast extract supplementation to molasses (M20) were evaluated individually and in combination. In addition, two quadratic models, using Box-Wilson central composite design, were used to correlate the phosphorus, magnesium and yeast extract concentrations that would achieve the highest biomass and lipid productivity. The study has shown that molasses (M20) supplemented with 336 mg/L K2HPO4, 0.17 g/L MgSO4 and 4.54 g/L yeast extract had the highest biomass productivity (80.7 mg/L/hour) and the highest lipid productivity (28.3 mg/L/hour). These productivity results were 1.44-fold and 2.42-fold higher than those of yeast extract-peptone-dextrose (YPD) broth, respectively. With enhanced biomass and lipid productivity, Yarrowia lipolytica can thus be used effectively in the fermentation industry. [ABSTRACT FROM AUTHOR]

Bu çalışmada Kilis ili toprak örneklerinden üreaz üretici Bacillus spp. suşları izole edilmiştir. B10 ve B11 olarak isimlendirilen suşlardan saflaştırılan intraselüler üreazın spesifik aktiviteleri 1.38±0.07 ve 1.22±0.02 µmol/min/mg’dır. B10 suşunun üreaz üretimini arttırabilmek için “Design Expert statistical software” (Design Expert 8.0.7)’in kullanıldığı Box Behnken deneme planı uygulanmıştır. Maksimum üreaz üretimi %5.00 üre, %3.00 sükroz ve %2.00 et özütü içeren besi ortamında gözlenmiş ve optimum koşullardaki en yüksek spesifik aktivite 1.498±0.05 µmol/min/mg olarak hesaplanmıştır.

The aim of the present study was to identify the optimum combination of dilution rate and depth of the culture to maximise the Arthrospira platensis BEA005B (Spirulina) productivity using 80 m2 raceway reactors. By varying these two main operational conditions, the areal biomass productivity of the reactors varied by over 55%. The optimum combination, optimised using a surface response methodology, was a depth of 0.10 m and a dilution rate of 0.33 day−1, which led to a biomass productivity of 30.2 g·m−2·day−1 on a dry weight basis when operating the reactors in semi-continuous mode. The composition of the produced biomass was 62.2% proteins, 42.5% carbohydrates, 11.6% ashes, and 8.1% lipids. The isolated proteins contained all the essential amino acids (except for tryptophan, which was not determined); highlighting the content of valine (6.8%), histidine (8.3%), and lysine (7.5%). The functional properties of the proteins were also assessed, demonstrating huge potential for their use in the development of innovative and sustainable foods. [ABSTRACT FROM AUTHOR]

The development of a multi-mycotoxins method using LC-MS/MS is necessary and it is clear that the development of such method involves many compromises in the choice of the different parameters. This review summarizes applications using conventional experimental designs and some recent studies using response surface methodology (RSM) as a mathematical modeling tool for the optimization of extraction procedures. The authors also discuss pros and cons of the different procedures. To our knowledge, it is the first review on experimental design for the development of multi-mycotoxin methods. This review could be useful in the development and optimization of LC-MS/MS methods with the aim of describing experimental design and variables (factors) that are likely to affect sensitivity and specificity. [ABSTRACT FROM AUTHOR]

This study aimed to optimize the growth conditions of the microalgae Auxenochlorella protothecoides to maximize the biomass and lipid content. The pH values and acetate concentrations of a tris-acetate-phosphate medium were varied for a photoheterotrophically grown culture of A. protothecoides. Approximately 23% of the microalgal biomass consisted of saturated fatty acids (SFAs). The highest lipid content (47.8%) was achieved with a medium containing 17 mM acetate at pH 6.2, and a medium containing 50 mM acetate at pH 5.8 resulted in the highest SFA content (43.7%). Surface response methodology was used to analyze the effects of two independent variables, pH (5.8–7.2) and acetate (0–35 mM), on lipid and biomass content. Four quadratic models, using the Box-Wilson central composite design, were proposed to correlate the optimal pH and acetate concentrations that would achieve the maximum biomass and lipid content. The study demonstrated that medium containing 24.4 mM acetate at pH 5.96 resulted in the highest lipid content (47.8%), and resulted in the highest biomass (1537 mg/L). Microalgae growth under these optimized conditions can enhance biomass and lipid productivity and can provide suitable conditions for high-quality biodiesel. [ABSTRACT FROM AUTHOR]

Carica fruit (Carica pubescens, Lenne) which is a unique-typical fruit and well listed as a geographical indication product of Wonosobo region Indonesia has high content of vitamin C and potassium (50-100 mg / 100g; 125 ppm). The basic formula (control) consisted of puree and filtrate carica 22.88%, kappa-carrageenan 0.11%, agar 0.08%, konjak glukomanan 0.11%, citric acid 0.08%, sucrose 15.26% and water up to 100%, respectively. The results showed that: 1) the formula with desirability value 0.91 consisting of puree: filtrate = 10,85: 14,5% and sucrose: low-calorie sugar brand X = 7,13: 1.4% resulted in maximum sensory response (sensory score range 1-9) of preference (score 5.5), in range response of elasticity and sweetness (score 5.9 and 5.4); 2) Compared to control, the optimum formula has higher sensory score of fruity flavor, sour aroma, acid taste, and softness (mouthfeel), while texture (springinss and rigidity), sweetness aroma and taste has no different; 3) The optimum formula has similar in hedonic preference with control; 4) Carica jelly drinks with optimum formula has lower carbohydrate, sugar, and energy values (13.59 and 7.4%wb; 40.52Kcal/100g, respectively) than controls (20.37 and 17.42 % wb; 83,16Kcal/100g, respectively).

Bamboo is abundantly and vastly available, which is known for its strength and verity of usage. In this work, the effect of acrylonitrile/MAPE/nano-clay on bamboo nanocomposites (BNCs) and its optimization were evaluated using response surface methodology (RSM). The developed BNCs were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC) to study their compositional, morphological, and thermal properties. Based on the BNCs, the response surface models were developed to predict the modulus of elasticity (MOE) and modulus of rupture (MOR) of the BNCs. The developed models fitted the experimental values with R2 close to 1 and residuals normal probability plot fitted to straight line. According to the models, the BNCs optimized values of MOE and MOR were higher compared to raw one. Scanning electron microscope (SEM) images showed that treatment on 8/12/60 BNC created a rough surface and eliminated hemicellulose on the surface of the bamboo, which improved the morphological properties, while XRD result on the 1/12/60 BNC showed an increase in the crystalline region than the amorphous region, which was due to the longer impregnation period. The melting and decomposition temperature of the BNCs had higher than the raw bamboo as indicated by TGA and DSC results. It is anticipated that the BNCs developed can compete against conventional hybrid nanomaterials with a great potential to be developed into eco-friendly nanocomposites used for interior and exterior construction application. [ABSTRACT FROM AUTHOR]

The present study evaluated the effect of multiple variables (drying time, drying temperature, biomass/solvent ratio, glass beads/biomass ratio, extraction time, and extraction speed) in the solubilization of three different phycobiliproteins (C-PC, APC, and PE) from a thermotolerant Oscillatoria sp. The strain was grown in BG11 media (28 °C, light: dark cycle of 12:12 h at 100 µmol·m−2·s−1, 20 days) and the experiments were conducted according to a two-level randomized factorial design with six center points (38 runs). Results show that biomass/solvent ratio, glass beads/biomass ratio, and extraction time, are the most significant variables in the extraction of all three proteins, whereas the glass beads/biomass ratio and extraction time significantly affect their purity. The optimized conditions allow a statistical increase in the concentration of C-PC, APC, and PE extracted from the biomass; however, the purity was lower in comparison with the expected value. The latter occurs due to a larger biomass/solvent ratio and longer extraction times, which enhanced the solubility of other hydrophilic metabolites (proteins and carbohydrates, etc.). [ABSTRACT FROM AUTHOR]

Recently, bismuth oxyiodide (BiOI) is an attractive semiconductor to use in heterogeneous photocatalysis processes. Unfortunately, BiOI individually shows limited photocatalytic efficiency, instability, and a quick recombination of electron/holes. Considering the practical application of this semiconductor, some studies show that synthetic zeolites provide good support for this photocatalyst. This support material permits a better photocatalytic efficiency because it prevents the quick recombination of photogenerated pairs. However, the optimal conditions (time and temperature) to obtain composites (BiOI/ synthetic zeolite) with high photocatalytic efficiency using a coprecipitation-solvothermal growth method have not yet been reported. In this study, a response surface methodology (RSM) based on a central composite design (CCD) was applied to optimize the synthesis conditions of BiOI/mordenite composites. For this purpose, eleven BiOI/mordenite composites were synthesized using a combined coprecipitation-solvothermal method under different time and temperature conditions. The photocatalytic activities of the synthesized composites were evaluated after 20 min of photocatalytic oxidation of caffeic acid, a typical organic pollutant found in agro-industrial wastewater. Moreover, BiOI/mordenite composites with the highest and lowest photocatalytic activity were physically and chemically characterized using nitrogen adsorption isotherms, scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and diffuse reflectance spectroscopy (DRS). The optimal synthesis conditions prove to be 187 °C and 9 h. In addition, the changes applied to the experimental conditions led to surface property modifications that influenced the photocatalytic degradation efficiency of the BiOI/mordenite composite toward caffeic acid photodegradation. [ABSTRACT FROM AUTHOR]

In this work, the landfill leachate of Fez city (Morocco) is characterized physicochemically and the feasibility to apply a Fenton process is evaluated. A design of experiments based on Box–Behnken combined with a response surface methodology was used to assess the effect of three operating variables (pH, Fe2+ and H2O2 dosages) on two target responses: COD and color removal. The results of the analysis of variances demonstrate that both responses are significantly affected by Fe2+ dosage and pH. Statistical and graphical analyses show that maximum efficiencies of 85% and 96% are obtained in terms of COD and color removal, respectively, when operating conditions are set in pH = 2.8, [Fe2+] = 1621 mg L−1 and [H2O2] = 2500 mg L−1. [ABSTRACT FROM AUTHOR]

Consumers are increasingly looking for foods, including wine, that are free of animal-derived proteins. This study seeks to evaluate patatin, a new, plant-based and allergen-free fining agent, by comparing it with the fining agents polyvinipolypyrrolidone, bovine serum albumin, and methylcellulose. Specifically, its effects on the phenolic profile of enological tannins were analyzed with four spectrophotometric assays: OD 280 nm, Folin–Ciocâlteu, Adams–Harbertson, and methylcellulose. In addition, changes in the polyphenol composition of Sangiovese red wine were determined by UV-Vis spectrophotometry and HPLC with adsorption trials, and the solid–liquid interaction in a wine solution was modeled by both Langmuir and Freundlich equations. Our findings highlight the occurrence of systematic proportional error between the selected spectrophotometric assays. As a result, direct comparisons of protein precipitation assays can be made only among results obtained with the same spectrophotometric method. However, it is clear that patatin has an impact on the phenolic profile of Sangiovese red wine: it removes simple phenolics (gallic acid, (+)-catechin, (–)-epicatechin, epicatechin gallate, syringic acid, fertaric acid, coutaric acid, and rutin) as well as both oligomeric and polymeric tannins to different extents. In concentrations of less than 1 g/L, the patatin isotherm showed a linear relation between the equilibrium concentration and the quantity absorbed, obeying the Freundlich model reasonably well (KF 1.46; 1/n 1.07; R2 0.996 with 1/n > 1). Thus, the adsorption process is strongly dependent on the fining dosage. [ABSTRACT FROM AUTHOR]

Managing the quality of pea-enriched cakes made from mixes of wheat and pea flours in various proportions (10, 35, and 60 wt% of pea, flour basis) and with various particle size distributions (0, 50, and 100 wt% of particles < 63 µm) is a challenge for the industry. A "multiobjective" model based on an I-optimal response surface design was set up in a previous study. It allows obtaining target cake structural and textural properties by adjusting several processing parameters (mixing speed and time, baking program). As the model's ability to correct the variations in cake properties due to variations in flour properties remained to be proven, two case studies concerning the proportion and the particle size of pea flour were studied. A variation of crumb stiffness (24 to 37 kPa), lightness (85.4 to 79.6 in L*), and cell fineness (4.9 to –4.8 in PC1 score) could be observed with the increase in the proportion of pea flour from 0 to 35 wt%, and these variations were properly corrected by the model (corrected values: 28 kPa; 83.2 in L*; 3.7 in PC1 score). A change in the particle size of pea flour caused variations in cake properties inferior to those due to processing reproducibility, except for cake symmetry (7.5 to 10.1 in symmetry index; corrected value: 7.2). A selection of products representative of the diversity of cakes from the original design space was investigated by 11 trained panelists through quantitative descriptive analysis. A convergence between sensory and instrumental results was found concerning structural and textural properties. Additional sensory perceptions such as beany attributes or in-mouth drying aftertaste were pointed out. [ABSTRACT FROM AUTHOR]

This paper presents a multi-objective design optimization of a power transformer to find the optimal geometry of its core and the low- and high-voltage windings, representing the minimum power losses and the minimum core and copper weights. The optimal design is important because it allows manufacturers to build more efficient and economical transformers. The approach employs a manufacturer’s design methodology, which is based on the usage of the laws of physics and leads to an analytical transformer model with the advantage of requiring a low amount of computing time. Afterward, the multi-objective design optimization is defined along with its constraints, and they are solved using the Non-Sorting Genetic Algorithm III (NSGA-III), which finds a set of optimal solutions. Once an optimal solution is selected from the Pareto front, it is necessary to fine-tune it with the 3D Finite Element Analysis (FEA). To avoid the large computing times needed to carry out the 3D Finite Element (FE) model simulations used in multi-objective design optimization, Response Surface Methodology (RSM) polynomial models are developed using 3D FE model transformer simulations. Finally, a second multi-objective design optimization is carried out using the developed RSM empirical models that represent the cost functions and is solved using the NSGA-III. The numerical results of the optimal core and windings geometries demonstrate the validity of the proposed design methodology based on the NSGA-III. The used global optimizer has the feature of solving optimization problems with many cost functions, but it has not been applied to the design of transformers. The results obtained in this paper demonstrate better performance and accuracy with respect to the commonly used NSGA-II.

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The magnetic Fe3O4 was synthesized by using a one-step solvothermal method. Then, anhydrous ethanol as a solvent, tetramethyl ammonium hydroxide (TMAOH) as an auxiliary agent, tetraethyl orthosilicate (TEOS) as a silicon source, and (3-aminopropyl) triethoxysilane (APTES) as amino source were used to prepare Fe3O4@mSiO2-NH2 by using the sol-gel method. Uniform design U14*(145) and the response surface method (RSM) were used to optimize the synthesis ratio. According to the results of TEM, SEM, N2 adsorption–desorption test, VSM, and XRD, it found that the best coating effect obtained when the relative molar ratio of TMAOH:TEOS:APTES:Fe3O4 was 5:4:6:0.45. The results of EDS and elemental analysis confirmed the success of amino group coating; VSM magnetization after surface modification was 32 emu/g; BET results show that specific surface area is 236 m2/g, size 5 nm, and the pore volume is 0.126 cm3/g. The removal of Cu2+, Zn2+, and Pb2+ by Fe3O4@mSiO2-NH2 was studied at the optimal initial pH value 6 of the adsorption test system. The isothermal adsorption results show that the Langmuir model and Redlich–Peterson model are more suitable than the Freundlich model to describe the adsorption behavior, and Cu2+, Zn2+, and Pb2+ adsorption is mainly single molecular layer. The maximum adsorption capacity qm of the Langmuir model for Cu2+, Zn2+, and Pb2+ removal was 48.04 mg/g, 41.31 mg/g, and 62.17 mg/g, respectively. The adsorption kinetic rates of Cu2+, Zn2+, and Pb2+ on Fe3O4@mSiO2-NH2 relatively more suitable for pseudo-second-order kinetic model, i.e., R2, were ranged between 0.995 and 0.999, and the suitable reaction time was 60 min. These results proved that Fe3O4@m-SiO2-NH2 prepared by using this method is easy to synthesize, has easy recovery, is ecofriendly, and can be potential adsorbent for Cu2+, Zn2+, and Pb2+ removal. [ABSTRACT FROM AUTHOR]

The aim of the present study was to identify the optimum combination of dilution rate and depth of the culture to maximise the Arthrospira platensis BEA005B (Spirulina) productivity using 80 m2 raceway reactors. By varying these two main operational conditions, the areal biomass productivity of the reactors varied by over 55%. The optimum combination, optimised using a surface response methodology, was a depth of 0.10 m and a dilution rate of 0.33 day−1, which led to a biomass productivity of 30.2 g·m−2·day−1 on a dry weight basis when operating the reactors in semi-continuous mode. The composition of the produced biomass was 62.2% proteins, 42.5% carbohydrates, 11.6% ashes, and 8.1% lipids. The isolated proteins contained all the essential amino acids (except for tryptophan, which was not determined); highlighting the content of valine (6.8%), histidine (8.3%), and lysine (7.5%). The functional properties of the proteins were also assessed, demonstrating huge potential for their use in the development of innovative and sustainable foods.

Particle size is a physical property that sometimes limits the quality of briquettes, so it is recommended to use different sizes in mixtures for their manufacture. The objective of this research was to evaluate the effect of different particle sizes of sawdust in mixtures on some physical, mechanical, and energetic properties of briquettes made from Pinus durangensis sawdust, as well as set the ranges within the appropriate values found to obtain desired values. Three particle sizes were established (large, medium, and small), and 10 mixtures were prepared using different percentages of each particle classification. The particle density, volumetric swelling, compressive strength, impact resistance index (IRI), and gross calorific value of the briquettes were evaluated. For the determination of optimal mixtures, the surface response methodology was used under a three-factor simplex-lattice model. The particle density values were in the range 0.92 to 1.02 g cm−3 and the volumetric swelling was 0.96 to 3.9%. The highest resistance to compression was 37.01 N mm−1, and the IRI was found in the range of 53 to 107%. The gross calorific values were from 19.35 to 21.63 MJ kg−1. The selection of different particle sizes for the mixtures increases the quality of the briquettes. [ABSTRACT FROM AUTHOR]

Consumers are increasingly looking for foods, including wine, that are free of animal-derived proteins. This study seeks to evaluate patatin, a new, plant-based and allergen-free fining agent, by comparing it with the fining agents polyvinipolypyrrolidone, bovine serum albumin, and methylcellulose. Specifically, its effects on the phenolic profile of enological tannins were analyzed with four spectrophotometric assays: OD 280 nm, Folin–Ciocâlteu, Adams–Harbertson, and methylcellulose. In addition, changes in the polyphenol composition of Sangiovese red wine were determined by UV-Vis spectrophotometry and HPLC with adsorption trials, and the solid–liquid interaction in a wine solution was modeled by both Langmuir and Freundlich equations. Our findings highlight the occurrence of systematic proportional error between the selected spectrophotometric assays. As a result, direct comparisons of protein precipitation assays can be made only among results obtained with the same spectrophotometric method. However, it is clear that patatin has an impact on the phenolic profile of Sangiovese red wine: it removes simple phenolics (gallic acid, (+)-catechin, (–)-epicatechin, epicatechin gallate, syringic acid, fertaric acid, coutaric acid, and rutin) as well as both oligomeric and polymeric tannins to different extents. In concentrations of less than 1 g/L, the patatin isotherm showed a linear relation between the equilibrium concentration and the quantity absorbed, obeying the Freundlich model reasonably well (KF 1.46; 1/n 1.07; R2 0.996 with 1/n > 1). Thus, the adsorption process is strongly dependent on the fining dosage.

Recently, bismuth oxyiodide (BiOI) is an attractive semiconductor to use in heterogeneous photocatalysis processes. Unfortunately, BiOI individually shows limited photocatalytic efficiency, instability, and a quick recombination of electron/holes. Considering the practical application of this semiconductor, some studies show that synthetic zeolites provide good support for this photocatalyst. This support material permits a better photocatalytic efficiency because it prevents the quick recombination of photogenerated pairs. However, the optimal conditions (time and temperature) to obtain composites (BiOI/ synthetic zeolite) with high photocatalytic efficiency using a coprecipitation-solvothermal growth method have not yet been reported. In this study, a response surface methodology (RSM) based on a central composite design (CCD) was applied to optimize the synthesis conditions of BiOI/mordenite composites. For this purpose, eleven BiOI/mordenite composites were synthesized using a combined coprecipitation-solvothermal method under different time and temperature conditions. The photocatalytic activities of the synthesized composites were evaluated after 20 min of photocatalytic oxidation of caffeic acid, a typical organic pollutant found in agro-industrial wastewater. Moreover, BiOI/mordenite composites with the highest and lowest photocatalytic activity were physically and chemically characterized using nitrogen adsorption isotherms, scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and diffuse reflectance spectroscopy (DRS). The optimal synthesis conditions prove to be 187 °C and 9 h. In addition, the changes applied to the experimental conditions led to surface property modifications that influenced the photocatalytic degradation efficiency of the BiOI/mordenite composite toward caffeic acid photodegradation.

The treatment of real textile wastewater by coagulation-flocculation (CF) using ferric chloride as coagulant and polymer as flocculant was optimized with the central composite design (CCD) based on response surfaces methodology. The independent variables considered were pH, coagulant, and flocculant dose. Their effects on the treatment were evaluated by the analysis of variance. The models are validated by the comparison between the predicted and experimental values, with a coefficient of determination reached a value above 93%, for all responses; removal efficiency of chemical oxygen demand (COD), biological oxygen demand (BOD5), turbidity, and color. The graphical representations of the models in the space of the variables enable us to determine the optimal conditions, which are pH = 8.1, a dose of FeCl3 = 0.8 g/L and a dose of flocculant = 2.6 mL/L. Under these conditions, the removal efficiency of COD, turbidity, color, and BOD5 achieved 95%, 92%, 96%, and 60% respectively. [ABSTRACT FROM AUTHOR]

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Astaxanthin (ASTX) has been reported as a potential therapeutic agent for hepatic fibrosis treatment. However, its therapeutic effect is limited due to low bioavailability and poor aqueous solubility. In this study, biopolymer-based nanoparticles were fabricated using stearic acid-chitosan conjugate (SA-CS) and sodium caseinate (NaCas) via ionic gelation. Its nanostructure was cross-linked using oxidized dextran (Odex) via Schiff base reaction. Concentration of cross-linker, cross-linking temperature and time were systematically optimized by response surface methodology (RSM) to achieve superior particulate properties and colloidal stability. The optimized nanoparticles exhibited a diameter of 120 nm with homogeneous size distribution. A good ASTX encapsulation capacity with up to 6% loading ratio and high encapsulation efficiency was obtained. The final ASTX concentration in nanoparticles was 140 μM. The aqueous dispersibility of encapsulated ASTX was greatly improved, which was confirmed by significantly increased ABTS radical scavenging capacity. Compared to the anti-fibrogenic effect of free ASTX in LX-2 cells, the encapsulated ASTX demonstrated dramatically enhanced cellular bioactivity, as evidenced by significantly lower TGFβ1-induced fibrogenic gene (ACTA2 and COL1A1) expression level, as well as α-SMA and COL1A1 protein levels. This study suggests that the as-prepared biopolymer nanoparticles hold promising features as an oral delivery vehicle for lipophilic bioactives. Unlabelled Image • Biopolymer ternary complex nanoparticles were developed for lipophilic bioactives. • The formulation was optimized via response surface methodology. • The aqueous dispersibility of encapsulated astaxanthin was enhanced. • The anti-fibrogenic activity of encapsulated astaxanthin was significantly improved. [ABSTRACT FROM AUTHOR]

In this study biodiesel was produced from waste sunflower cooking oil and ethanol using N , N ′, N ″-tris(3-dimethylaminopropyl)-guanidine as new catalyst, which allows to avoid unwanted side-reaction of saponification. The influence of process variables on the conversion was investigated using experimental design and response surface methodology. Independent factors were varied in the following range: molar ratio of alcohol/oil from 3:1 to 15:1; catalyst concentration from 0.5 to 3 wt%; reaction temperature from 40 to 80 °C; and reaction time from 40 to 200 min. An empirical model of the process was developed. With this model and the goals of minimizing the independent factors in the tested range and maximizing the conversion, the optimization resulted in the following conditions: 1.13 wt% of catalyst, a molar ratio of 11.16:1, temperature of 67.96 °C, and a reaction time of 80 min. With those optimal conditions, the conversion predicted by the model was 94.6%. • Biodiesel production from waste cooking oil and bioethanol with guanidine catalyst. • Process optimization for: temp., time, wt% catalyst, and molar ratio of reactants. • The optimal conditions were: oil/alcohol = 1/11.16, temp. = 68 °C, w catalyst = 1.13 wt%. • At optimal conditions the conversion was 94.6%. [ABSTRACT FROM AUTHOR]