Face-centered Central Composite Design Research Articles

Advancements in Soft Soil Stabilization by Employing Novel Materials through Response Surface Methodology

Stabilization using industrial by-products is presently gaining importance in the construction sector for improving the geotechnical characteristics of soft soils. The optimum dosage of stabilisers has become of great interest to experimenters in terms of improved strength, time, and economy for construction projects. This work presents the utilization of biomedical waste ash for improving the strength of soft soil. In this paper, response surface methodology (RSM) was adopted to determine the optimum combination curing period (C) and biomedical waste ash (BA) quantity for attaining the maximum unconfined compressive strength (UCS) of soft soil and to reduce the number of trial tests required. The response factors C and BA were varied from 0 to 14 days and 4% to 20%, respectively, and the experiments were conducted according to the experimental plan provided by the RSM design. Based on a Face-centred Central Composite Design (FCCCD), a mathematical equation was created for the experimental results. Analysis of variance (ANOVA) was used to determine the generated model’s significance, and the results indicated a statically significant model (p ≤ 0.05). The results revealed that the curing period imparts more influence towards strength improvement, and the optimum dosage was 19.912% BA, with curing of 14 days to yield a maximum UCS of 203.008 kPa. This optimization technique may be suggested to obtain a preliminary estimation of strength prior to stabilization.

Development of optimum performance model during spark-eroded processing of rheocasted Al6061/Cenosphere MMCs

ABSTRACT In the present study, an improved wettability casting route was used to prepare lightweight structural materials. Using the compo casting process, an Al6061 alloy was created with cenosphere particles at various weight percentages (2, 4, 6, and 8 wt%). The molten aluminium slurry incorporated hollow alumina silicate particulates. X-ray diffraction (XRD) analysis of the aluminium matrix composites (AMCs) confirmed the presence of cenospheres without any intermetallic components. Further processing of the metal matrix composites (MMCs) was conducted using electric discharge machining (EDM) with a circular copper electrode. The EDM process parameters were controlled to measure response variables such as material removal rate (MRR), tool wear rate (TWR), and surface roughness (SR). The effects of different combinations of machining parameters – including pulse current, pulse-on time, reinforcement percentage, and flushing pressure – on these performance characteristics were observed. Experimental trials were designed using the face-centred central composite design (CCD) of the response surface methodology (RSM). Optimal process variable conditions led to significant improvements in surface finish. Additionally, an artificial neural network (ANN) model was used to determine the best conditions for EDM processing. The ANN model demonstrated a strong correlation coefficient of 0.99 between the predicted and experimental values of MRR, TWR, and SR.

Application of design of experiment for quantification of 71 new psychoactive substances in influent wastewater

BackgroundNew psychoactive substances (NPS) are of public health concern due to their sporadic proliferation and the dearth of information on toxicity when consumed. In addition to seized data from forensic and toxicology reporting, wastewater analysis serves as a complimentary tool for NPS surveillance. A method to detect 71 NPS by simple filtration followed by liquid-chromatography tandem mass spectrometry was developed to detect multiclass NPS consisting of arylcyclohexylamines, designer benzodiazepines, synthetic cannabinoids, synthetic opioids, phenethylamines, synthetic cathinones, tryptamines, and indole alkaloids. ResultsIn this work, the influential factors for electrospray ionisation were identified and optimised using the fractional factorial design and face-centred central composite design, respectively. The filtration loss during sample clean-up was assessed for all compounds. The final method was validated and applied to wastewater collected from a music festival held in Queensland in 2022. The validated method had linearity between 0.5 ng L−1 and 5000 ng L−1, the limit of quantification (LOQ) ranges from 0.6 ng L−1 to 70 ng L−1, precision within ±20 %, accuracy ranges from 70 % to 120 %, and matrix effect ranges from soft (0 %–20 %) to medium (20 %–50 %) for the majority of the compounds. NPS detected in the festival were 2-fluorodeschloroketamine, 7-hydroxymitragynine, mitragynine, N,N-dimethylpentylone, pentylone, phenibut, and O-desmethyltramadol. SignificanceSystematic electrospray ionisation optimisation using the design of experiment for a large method is practical and provides in-depth chemical information on studied compounds. The optimised method demonstrated the applicability of analysing samples collected from a festival in this work.

Optimised phycoerythrin extraction method from Porphyridium sp. combining imidazolium-based ionic liquids

Phycoerythrin (PE) extraction from Porphyridium sp. was studied employing ultrasound-assisted extraction combined with aqueous mixtures of two imidazolium-based ionic liquids (ILs) simultaneously, marking a significant novelty. A face-centred central composite design and response surface optimised PE yield (EPE), considering the effects of ionic liquid concentration (IL), [Emim][EtSO4]/[Bmim][EtSO4] mass ratio (E/B), biomass concentration (BM), and time (t). Improvements in EPE by 300 % and 115 % were achieved compared to a phosphate buffer solution and the freeze-thaw method, respectively. Temperature and pH effects were examined independently, leading to the determination of optimal operating conditions: BM = 10 mg mL−1, IL = 18.6 wt%, E/B = 0.78/0.22, t = 10 min, T = 35 °C, and pH = 7.5. Results indicated the potential for reusing the ILs for at least five consecutive extraction cycles, maintaining an EPE of 94.2 % compared to fresh ones. This underscores the success and innovation of the developed technology in enhancing PE extraction from Porphyridium sp.

Application of central composite design (CCD)-response surface methodology (RSM) for optimization of heat transfer in dusty nanofluid flow with velocity slip

Background and Purpose The consequence of thermal radiation is scrutinized on the heat transport of Nano-diamond/silicon oil and silver/silicon oil nanofluids through a stretching endless plate. The single phase (Tiwari and Das) model is employed for nanofluid. The major objective of this study is to optimize the RSM-based Central composite design modeling to optimization of the heat transfer in dusty Oldroyd-B nanofluid across stretching surface. Additionally the velocity slip effect is considered. The dust particle phase is also taken into account. The significance of viscous dissipation, joule heating, inclined magnetic field with convective condition is investigated. Methodology The partial differential equations are developed under consideration, then transform to ODE’s by utilizing similarity tools. The transformed model of ODE’s is tackled numerically via bvp4c MATLAB tool with shooting algorithm. The effect of magnetic parameter, fluid interaction parameter, nanoparticle volume fraction, slip parameter and temperature interaction parameter on velocity field and temperature distribution of fluid phase and dust phase is investigated. Furthermore the Nusselt number on the wall is observed for interactive parameters of mass concentration of dust particles, fluid particles interaction parameter for velocity and unsteady parameters utilizing the face-centered Central Composite design (CCD) of the Response Surface Methodology (RSM). Additionally, Analysis of Variance (ANOVA) algorithm and 3D plots are utilized to examine the consequence of experimental design parameters via the response. The recommended model significance has been analyzed in conditions of correlation coefficient ( R 2 ), mean square error (MSE), root means square error (RMSE), prediction standard error to acknowledge the most excellent strong. Results The difference between the Predicted R2 of 0.9467 and the Adjusted R2 of 0.9867 is less than 0.2, which is assumed to be a reasonable concurrence. Furthermore results of the current analysis indicate that velocity gradient for nanofluid is diminishes for larger fluid particle interaction parameter for velocity, while the dust phase velocity is improved. The increment in Temperature gradients is observed via increasing values of the nanoparticle fraction and temperature base fluid particle interaction parameter. From the results it is concluded that skin friction coefficient is reduced with larger magnetic parameter for both mono nanofluids. Furthermore the heat transfer rate is increased by increasing the thermal radiation parameter for both mono nanofluids. It is concluded that silver/silicon oil nanofluid play a higher role in heat transportation as compare to Nano-diamond/silicon oil.

Optimizing CuO nanoparticle synthesis via walnut green husk extract utilizing response surface methodology

Fabrication of CuO nanoparticles (NPs), popular nanostructures, through green synthesis using plant extracts, offers distinct advantages, fostering their broad application. In this study, CuO NPs were synthesized utilizing walnut green husk aqueous extract, and their production was optimized by investigating the impact of three factors: extract volume, copper acetate concentration, and reaction time, employing response surface methodology (RSM) with a face-centered central composite design (CCD). A statistically significant and adequate linear model (p-value <0.0001, R2: 0.98) effectively described the influence of these factors on the CuO NPs production, with the extract volume exerting the highest impact, followed by copper acetate concentration, and reaction time demonstrating the least impact. The NPs, produced under conditions of 1 mM salt concentration and 1 mL extract per 10 mL reaction over 1 h, were characterized. Field Emission Scanning Electron Microscopy (FESEM) and Ultraviolet–Visible (UV–vis) spectroscopy revealed nearly spherical NPs with an average size of 54.03 nm and a surface plasmon resonance (SPR) peak at 194 nm. Energy Dispersive X-ray (EDX) analysis and Fourier-Transform Infrared (FTIR) spectroscopy confirmed the elemental composition and the presence of extract biomolecules in the NP coating. The fabricated NPs exhibited an amorphous and monodisperse nature, with an average hydrodynamic diameter of 82.61 nm.

NaAlO2/CuFe2O4 as a novel basic magnetic heterogeneous catalyst for effective biodiesel production: Synthesis, characterization, and optimization via RSM-FCCD modeling approach

This research focus on the development of a novel and superior basic magnetic heterogeneous catalyst, using NaAlO2 as an active species supported in CuFe2O4 to produce biodiesel. Thus, a series of catalysts have been synthesized by means of conventional and low-cost methods. The features of catalyst have been elucidated through techniques such as basicity, XRD, FTIR, SEM, EDS, TG/DTG and VSM. To optimize the biodiesel’s ester content, the face-centered central composite design with the response surface methodology, was employed to assess the effect of the aspects on the process: reaction temperature, MeOH:oil molar ratio, catalyst dosage and time. The regression model presented R2 = 0.9394 and experimentally reached a maximum ester content of 95.9 % attributed to the biodiesel attained under the optimal reaction conditions: temperature of 95.0 °C, MeOH:oil molar ratio of 13:1, catalyst dosage of 8.0 % and time of 60.0 min. The catalyst presented a stable catalytic performance during four transesterification cycles (>90.0 %) and an efficient magnetic property for the catalyst separation and recovery process (Ms = 23.62 emu g−1). The biodiesel’s physicochemical properties were in compliance with ASTM D6751 standard. Finally, this extensive study reveals the basic magnetic heterogeneous catalyst as a practical and promising alternative to produce a sustainable biofuel.

Pomegranate seed as a novel source of plant protein: Optimization of protein extraction and evaluation of invitro digestibility, functional, and thermal properties.

This research was carried out to optimize the extraction process of proteins from pomegranate seeds and characterize their invitro digestibility as well as their thermal and functional properties. For this purpose, the study screened five parameters (liquid/solid ratio, pH, temperature, NaCl concentration, and time) that could potentially influence the extraction process. This screening was conducted using a two-level Placket-Burman design (PBD). The significant parameters (pH and NaCl concentration) were subsequently optimized using a three-level face-centered central composite design (FCCD) to determine the optimum extraction conditions. A maximum protein recovery of 83.8% was obtained at pH 11.0 and NaCl concentration of 0.0 M. Pomegranate seed protein isolate (PSPI) with a protein content of 92.4% (w/w) was obtained through the isoelectric precipitation of pomegranate seed protein extracted under the optimized conditions. An emulsifying activity index of 14.1 m2 g-1 was observed at the isoelectric pH, where the emulsion stability index was at 8.2%. PSPI also showed high water- and oil-holding capacities (3.7 and 4.3 g g-1, respectively). The essential amino acid levels in PSPI (except for valine and isoleucine) exceeded the recommended amounts set by WHO/FAO/UNU for adults, highlighting its high nutritional value. Based on thermal analysis data, denaturation of PSPI could occur at 89.5°C. The invitro digestibility of PSPI was found to be 74.3%. PSPI shows a potential as a novel ingredient for substituting animal-based proteins in various food applications.

Development of a design of experiments (DOE) assistant modified QuEChERS method coupled with HPLC-MS/MS simultaneous determination of twelve lipid-soluble pesticides and four metabolites in chicken liver and pork

A modified QuEChERS method combined with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed for the determination of twelve lipid-soluble pesticides and four metabolites in chicken liver and pork. The QuEChERS method was optimized using two models, Plackett-Burman design and Central Composite Face-centered design, which enhanced its science and accuracy, making the optimization process more efficient and precise. Under optimal conditions, all coefficients of determination were > 0.9916. Limits of detection and limits of quantitation were 0.4–3.0 μg/kg and 1.0–10.0 μg/kg, respectively. In chicken liver, the recoveries (except for haloxyfop, haloxyfop-methyl, haloxyfop-etotyl, clodinafop-propargyl, and clodinafop) were 75.7–109.3% with relative standard deviations (RSDs) of 0.6–9.8%. In pork, the recoveries (except for difluorenican) were 73.4–104.7% with RSDs of 1.1–9.9%. Abnormal recoveries observed in this study could be attributed to the presence of esterase in chicken liver and pork. In addition, the method has been successfully applied to the detection of real samples. This study not only provides valuable data support for establishing maximum residue limits of target pesticides in chicken livers and pork, but also contributes an efficient and reliable detection tool for the animal-derived food safety monitoring system.

Optimising High-Pressure Processing (HPP) for Optimal Total Phenolic and Flavonoid Content in Kelulut (Stingless Bee) Honey

High-pressure processing (HPP) has the potential to enhance the total phenolic and flavonoid content (TPC and TFC) in Kelulut honey (KH). However, KH’s inherent variability possesses challenges in optimising these phytochemicals. This study hence explores the optimisation of KH through HPP, focusing on TPC and TFC. The Face-centered Central Composite Design (FC-CCD), involving two factors with three levels each (pressure of 200, 400, and 600 MPa, and time of 5, 10, and 15 min), was applied to investigate two response variables (total phenolic and flavonoid content). The optimisation identified the optimal parameters as 200 MPa for 15 min, with a desirability of 0.986, indicating precise modeling. Compared to other pressures (400 and 600 MPa) at common processing time (15 minutes), 200 MPa recorded higher TPC and TFC with differences of 25.71% to 30.92% and 13.78% to 14.19%, respectively. A verification step revealed that HPP-KH at 200 MPa for 15 minutes yielded a TPC of 15.278 ± 0.525 mg GAE/100 g and a TFC of 38.274 ± 1.980 mg RE/100 g, indicating the precise accuracy of the quadratic modeling. However, this discovery contradicts the consensus that pressures above 500 MPa increase TPC and TFC. Consequently, it underscores the need for tailored high-pressure strategies in KH processing, offering essential insights for industry applications and further research endeavors.

A sustainable green-approach for biofabrication of chitosan nanoparticles, optimization, characterization, its antifungal activity against phytopathogenic Fusarium culmorum and antitumor activity.

Chitosan is a natural non-toxic, biocompatible, biodegradable, and mucoadhesive polymer. It also has a broad spectrum of applications such as agriculture, medical fields, cosmetics and food industries. In this investigation, chitosan nanoparticles were produced by an aqueous extract of Cympopogon citratus leaves as a reducing agent. According to the SEM and TEM micrographs, CNPs had a spherical shape, and size ranging from 8.08 to 12.01 nm. CNPs have a positively charged surface with a Zeta potential of + 26mV. The crystalline feature of CNPs is determined by X-ray diffraction. There are many functional groups, including C꞊C, CH2-OH, C-O, C-S, N-H, CN, CH and OH were detected by FTIR analysis. As shown by the thermogravimetric study, CNPs have a high thermal stability. For the optimization of the green synthesis of CNPs, a Face centered central composite design (FCCCD) with 30 trials was used. The maximum yield of CNPs (13.99 mg CNPs/mL) was produced with chitosan concentration 1.5%, pH 4.5 at 40°C, and incubation period of 30 min. The antifungal activity of CNPs was evaluated against phytopathogenic fungus; Fusarium culmorum. A 100% rate of mycelial growth inhibition was gained by the application of 20mg CNPs/mL. The antitumor activity of the green synthesized CNPs was examined using 6 different cell lines, the viability of the cells reduced when the concentration of green synthesized CNPs increased, the IC50 dose of the green synthesized CNPs on the examined cell lines HePG-2, MCF-7, HCT-116, PC-3, Hela and WI-38 was 36.25 ± 2.3, 31.21 ± 2.2, 67.45 ± 3.5, 56.30 ± 3.3, 44.62 ± 2.6 and 74.90 ± 3.8; respectively.

Hydrothermal Co-Liquefaction of Food and Plastic Waste for Biocrude Production

In this study, hydrothermal co-liquefaction of restaurant waste for biocrude production was conducted. The feedstock was resembled using the organic fraction of restaurant waste and low-density polyethylene, polypropylene, polystyrene, and polyethylene terephthalate, four plastic types commonly present in municipal solid waste. Using design of experiment and a face-centered central composite design, three factors (feedstock plastic fraction, temperature, time) were varied at three levels each: feedstock plastic fraction (0, 0.25, 0.5), temperature (290 °C, 330 °C, 370 °C), and reaction time (0 min, 30 min, 60 min). The literature reports positive synergistic interactions in hydrothermal co-liquefaction of biomass and plastics; however, in this work, only negative synergistic interactions could be observed. A reason could be the high thermal stability of produced fatty acids that give little room for interactions with plastics. At the same time, mass might transfer to other product phases.

Statistical optimization for greener synthesis of multi-efficient silver nanoparticles from the Hypocrea lixii GGRK4 culture filtrate and their ecofriendly applications

The culture filtrate of Hypocrea lixii GGRK4 played a vital role as a reducing and stabilizing agent in the mycosynthesis of silver nanoparticles (AgNPs) using silver nitrate (AgNO3). The extracellular extract derived from fungi emerged as a noteworthy option for synthesizing AgNPs due to its potential composition of metabolites, including enzymes and other bioactive substances. Hence, the presence of a dark brown color serves as a key indicator for the biosynthesis of AgNPs through the reduction of Ag (I) ions to Ag by the fungal culture filtrate. To facilitate the synthesis of AgNPs, a combination of hybrid technologies, specifically the “one factor at a time” approach and statistical tools such as response surface methodology, was used using a face-centered central composite design (FCCCD). Utilizing a modified CX medium with pH of 5.02 supported the fungi synthesizing AgNPs at a temperature of 30°C. The multi-efficient AgNPs were characterized through various techniques, including UV–visible spectrophotometry, zeta size and potential analysis using a zeta size analyzer, transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and fluorescence spectroscopy. The biosynthesized AgNPs have significant associated functional groups, revealed by FTIR analysis. TEM histogram analysis showed that these multi-efficient AgNPs have a size of 17.34 nm. Similarly, they have emission and excitation spectra of 450 nm and 390 nm, respectively, revealed by fluorescence spectrum analysis. Compared to the standard, the biosynthesized AgNPs have significant antibacterial and free radical scavenging properties and dye degradation capability. Additionally, the half-maximal inhibitory concentration (IC50) value was found statistically significant based on t-test analysis. Finally, the biosynthesized AgNPs could be used in potential applications encompassing ecofriendly degradation, antimicrobial activity, and therapeutic applications, such as free radical scavenging properties.

Bioactive extracts from grape (Vitis vinifera L. cv. País) leaves: Characterization and encapsulation in poly-3-hydroxybutyrate-co-3-valerate microparticles

Vitis vinifera var. L. País leaf extract, previously characterized, was microencapsulated by emulsion-solvent evaporation method using two different procedures: the conventional dropwise and micromixer device. The poly-3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV) was used as encapsulating polymer. In addition, the effect of extraction time and ethanol:water ratio on the yield and the content of bioactive compounds of grape leaf extract obtained by Soxhlet method was determined using the face-centered central composite design. The highest bioactive compound were obtained using a 70:30 ethanol:water solvent ratio during 4 cycles. This extract is mainly composed of cinnamic acid, quercetin-3-glucoside and quercetin-3-glucorinide, containing 3.56, 2.08 and 1.19 mg g−1 extract, respectively. The total polyphenol content determined by Folin Ciocalteu method was 164 ± 14 mg GAE g−1 extract. The microparticles (2–3 μm) had spherical shape with rough and porous surface. The encapsulation efficiency was 15.1% and 60.6% for the PHBV microparticles prepared using conventional dropwise and micromixer device, respectively. The antioxidant activity present in the original extract was preserved around 50%–80% and 20%–70% in the loaded microparticles. The best results were achieved when grape leaf extract was encapsulated using micromixer device. The cell viability assay in 3T3-L1 fibroblasts, showed that loaded microparticles are not cytotoxic. In conclusion micromixer device showed to be effective for the microencapsulation of grape leaf extract using PHBV as encapsuling polymer.

Optimization of barrel temperature and feed moisture content for better physicochemical and sensory properties of extruded snacks from blends of finger millet, sweet potato, and soybean composite flour using response surface methodology

Extruded snacks are commonly made with cereals with good expansion properties but low in essential nutrients such as protein and vitamins. The incorporation of legume and vegetable crops into cereal improves the nutritional value of cereal-based extruded snacks. This study aimed to develop a nutrient-rich optimized extruded snack by incorporating orange-fleshed sweet potato, finger millet, and soybean flour. The extrusion processing conditions were barrel temperature (90–130 °C) and feed moisture content (20–26%). Thirteen treatment combinations were generated for this experiment using a face-centered central composite design. Standard methods were used to evaluate the effect of barrel temperature and feed moisture content on extruded snacks' nutritional, anti-nutritional, physical, functional, and sensory acceptability. The data were analyzed, and processing conditions were optimized using the response surface methodology of Design Expert software version 13. Multiple regression analysis showed significant effects (p < 0.05) of the independent variables on moisture, protein, fat, beta-carotene, bulk density (BD), hardness, expansion ratio (ER), water absorption index (WAI), water solubility index (WSI), and overall acceptability of the extrudates. The optimum response of 14.06% protein, 3.26% ash, 69.12% carbohydrate, 6.477 mg/100 g beta-carotene, 0.36 g/ml bulk density, 2.72 Expansion ratio, 87.28 N hardness, 4.34 g/g Water absorption index, 22.34% Water solubility index, and overall acceptability of 3.30 was achieved at an optimal barrel temperature of 114.5 °C and feed moisture content of 20%. The obtained result suggests that barrel temperature and feed moisture content had a significant influence (p < 0.05) on the measured quality properties of the extrudates.

SURFACE ROUGHNESS OF Ti6Al4V ALLOY PRODUCED BY LASER POWDER BED FUSION

Controlling the surface roughness of materials manufactured by laser powder bed fusion (L-PBF) is critical for achieving functional performance of components and improving their mechanical properties. This is important for components whose surfaces cannot be post-treated using subtractive methods. In this study, the surface roughness has been investigated by applying different laser power and scanning speed combinations. Furthermore, potential effects of different locations on the build platform have been considered as well. The regression models have been developed using significant predictor variables, with their levels defined using face-centered central composite design. The analysis of variance (ANOVA) procedure has been used to evaluate the statistical significance of factors and model performances for each prediction variable. It has been found that the average surface roughness of L-PBF Ti6Al4V alloy can be described with high fitting accuracy using laser power and scanning speed as predictor variables. The position of specimens on the build platform showed no statistically significant effect on the average surface roughness. The experimental research and statistical analysis reported in this paper will contribute to a better understanding of how position, laser power, and scanning speed influence the average surface roughness of L-PBF Ti6Al4V alloy.

Face-Centered Central Composite Design for the Optimization of the Extraction of Phenolic Compounds from Kernels and Shells of Raphia farinifera and Evaluation of the Antioxidant, Antimicrobial, and Anti-Inflammatory Activities

This study reports the extraction of phenolic compound from shells and kernels of the Raphia farinifera fruit and the biological activities of the extract. A face-centered composite design was established to optimize the extraction conditions: ethanol/water ratio (0-100%), solvent/powder ratio (10-30 mL/g), and extraction time (90-180 min). Subsequently, the extracts obtained under the optimal conditions were used for the evaluation of the radical scavenging capacity, the capacity to chelate ferric ions, and the antimicrobial and anti-inflammatory activities. The optimal extraction conditions for the shells are an extraction time of 134.24 min, 65% ethanol in water, and a solvent/substrate ratio of 21.16 mL/g, and for the kernel, an extraction time of 180 min, 94.3% ethanol in water, and a solvent/substrate ratio of 18.6 mL/g. In these conditions, the phenolic compounds were 95.36 mg EAG/L for the shell extract and 139.72 mg EAG/L for the kernel extract. The antioxidant activity revealed that the half-maximal inhibitory concentrations (IC50) of the kernel extracts are 22.32 μg/mL and 55.73 μg/mL for the shells. A reducing activity of Fe 3+ ions with an activity of 308.39 μg EAA/mg for the kernel extracts and 293 μg EAA/mg for the shells was observed. B. cereus was the most sensitive microorganism with a minimum inhibitory concentration (MIC) equal to the minimum bactericidal concentration (MBC) with a value of 156.25 ppm for the kernel extract while the shell extract showed MIC of 625 ppm and MBC of 2500 ppm. The IC50 values for the denaturation of proteins by extracts of shells and kernels are 0.76 μg/mL and 0.56 μg/mL, respectively. Membrane stabilization revealed IC50 values of 1054.54 μg/mL and 1339 μg/mL for the shell and kernel extracts, respectively. This work has shown the potential of Raphia farinifera extracts for the food industry and cosmetics.

Application of Response Surface Methodology Using Face-centered Central Composite Design for Studying Long-Term Stability of Gliclazide-Loaded Multiparticulate Systems

The appropriate design of experiments (DoE) could support post-approval lean-stability approaches. A three-factor three-level face-centered design was constructed to evaluate the long-term stability of gliclazide (GLZ) alginate-gelatin beads. The formulation variables were GLZ%(X1), alginate:gelatin ratio(X2), and glutaraldehyde%(X3). The studied responses included GLZ release at predefined intervals in 0.1 N HCl (2 h) followed by phosphate buffer (pH 7.4). Model-dependent and independent approaches were utilized for comparison. DoE-model validation and reduction were implemented. All the studied formulations showed non-significant changes in the particle size (p > 0.05) and most of them showed similar release profiles before and after storage. The directions of the relationships between the factors' main effects and the responses (Y1:Q0.5h, Y2:Q2h, and Y3:Q4h) remained unchanged after storage. The optimal factor settings based on the proposed optimization criteria were defined. The optimized formulations (OP-1 and OP-2) showed non-significant changes in the particle size after storage. The release profiles and kinetics of OP-1 and OP-2 remained unchanged after storage. No chemical change was indicated (FT-IR). DSC-thermograms of OP-1 indicated GLZ conversion to a more stable polymorph after storage. While OP-2 showed a change in GLZ crystallinity. The stored and fresh beads’ surfaces after GLZ release were almost similar. DoE could be utilized to evaluate, optimize, and predict the effects of different formulation variables on the long-term stability of GLZ alginate-gelatin beads.

Optimization of Hydrolysis Conditions, Isolation, and Identification of Biologically Active Peptides Derived from Acheta domesticus for Antioxidant and Collagenase Inhibition.

The study aimed to optimize hydrolysis conditions and isolate and identify bioactive peptides with anti-skin aging effects from Acheta domesticus (house cricket). A. domesticus proteins underwent hydrolysis using Alcalase® and optimized conditions using response surface methodology through a face-centered central composite design. Variable controls (enzyme-substrate concentration (E/S), time, and temperature) were assessed for their impact on activities against collagenase, 2,2-diphenyl-1-picrylhydrazyl radical (DPPH●), and degree of hydrolysis of protein hydrolysate (PH). PH was also investigated for composition, anti-skin aging, and anti-inflammatory effects. Amino acid sequences with potent anti-skin aging activity were isolated and identified using ultrafiltration, gel filtration chromatography, and liquid chromatography coupled with tandem mass spectrometry, employing de novo sequencing. Optimal conditions for producing PH with maximum anti-skin aging activity were an E/S concentration of 2.1% (w/w), 227 min, and 61.5 °C. Glutamic acid was a predominant amino acid and PH exhibited a molecular weight below 15 kDa. Additionally, PH displayed significant activities against collagenase, hyaluronidase, DPPH●, lipid peroxidation, and NF-κB-mediated inflammation (p < 0.05). Three novel anti-skin aging peptides were identified-Ala-Val-Thr-Lys-Ala-Asp-Pro-Tyr-Thr-Asp-Gln, Thr-Val-Met-Glu-Leu-Asn-Asp-Leu-Val-Lys-Ala-Phe, and Val-Pro-Leu-Leu-Glu-Pro-Trp-exhibiting the most potent collagenase and DPPH● inhibition. Therefore, this study proposed that PH, produced with Alcalase® under optimal conditions, emerges as a promising substance with potent anti-skin aging activity for the cosmeceutical industry.

Development and characterization of gelatin-based biodegradable films incorporated with pistachio shell hemicellulose

This study aimed to incorporate pistachio shell hemicellulose into a film of gelatin and glycerol for the production of biodegradable films. The gelatin and glycerol are chosen because of their functional properties, which make it extensively used in food industry. The film composition was defined after a statistical optimization by central composite face-centered design and response surface methodology. The hemicellulose/gelatin ratio of 35.93% and the glycerol ratio of 18.02% were the optimum conditions to obtain lower film water solubility, higher tensile strength, and elongation at break values. The physical, structural, mechanical, and barrier properties of the developed hemicellulose-gelatin film were analyzed and compared with those of the gelatin film. Tensile strength and film water solubility values were reduced significantly with hemicellulose incorporation from 20.41 to 16.64 MPa and 49.57 to 39.21%, respectively, while EB was enhanced by 4.34 times. In addition, hemicellulose incorporation enhanced the water vapor permeability and the film degradation in the soil. The films were also examined by Fourier transform infrared spectroscopy and differential scanning calorimetry. The novelty of this study is to use pistcahio shell hemicellulose in the production of an edible film for the first time.