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In this study, investigation of bioaugmentation and biostimulation process parameters’ influence on biodegradation effectiveness of bacteria isolates in a crude oil polluted soil for 60 days was conducted. A native environment of crude oil polluted site was considered for bacteria isolation. Dilution plate technique was used for bacteria culturing under laboratory conditions. Central composite design embedded in design expert software was used for the design of experiment and optimum point prediction. The influence of nitrogen:phosphorus nutrient ratio and bacteria concentration at varying crude oil concentration and soil pH on percentage of total petroleum hydrocarbons (TPH) biodegraded was investigated. Biostimulation was highly significant on the percentage of TPH biodegraded as revealed by experimental results. Degradation efficiency of 93.75% was obtained for a soil pH of 10 contaminated with 100 g/Kg of crude oil using 600 cell/g of bacteria supplemented with 8 g/g of nitrogen-phosphorus ratio. The model developed was effective for future prediction with better correlation between experimental and predicted values. A biodegradation efficiency of 77.42% was achievable at the optimum predicted point by central composite design. Hydrocarbons biodegradation in the crude oil contaminated soil via the action of supplemented bacteria isolates was revealed. Conclusively, bacteria isolates from native polluted site could be applied as effective scavenger for hydrocarbons in crude oil contaminated soil.

Response surface methodology accompanied by Central Composite Design (CCD) was employed in this study to optimize Alternanthera spp-based phytoremediation process for the removal of acetaminophen and methylparaben individually. Two operational variables, including concentration (A) (20, 60,100 mg/L) and sampling time (B) (7, 14, 21, and 35 days) were involved in the study for removal efficiency (Y) as response. CCD had required a total of 18 experiments for each compound. Analysis of variance (ANOVA) was conducted to verify the adequacy of the proposed mathematical models and revealed good agreement with the experimental data. The observed R2 values (0.9732 and 0.9870), adjusted R2 (0.9620 and 0.9816) and predicted R2 (0.9383 and 0.9721) for AC and MP, respectively, indicated that the developed models were significant at the 95% probability level. Concentration factor was found to be not significant in the mathematical models; in contrast, sampling time was found to be of a crucial role. The removal of AC and MP were 89.23% and 64.48% at optimum conditions of A = 100 mg/L and B = 35 days respectively. Validation test confirmed the predicted results attained by Central Composite Design, as the removals achieved at the optimum conditions was 91.04% and 59.17% for AC and MP, respectively, which were in good agreement with the results proposed by the theoretical design.

The separation of glycerol from biodiesel in accordance with ASTM standards is critical. Conventional separation technology has not proven to be effective. Membrane technology is a viable and environmental friendly method of separating impurities from biodiesel. In this study, application of three different sizes ceramic membranes for separating glycerol from biodiesel is evaluated. The impact of process parameters such as average pore size, pressure and ethanol concentration on glycerol separation is evaluated using design expert software. The main aim of the present study is to address the separation and optimization of free glycerol from biodiesel using response surface methodology in combination with central composite design. Three pore-sized ceramic membranes (0.1, 0.2, and 0.3 µm) were used in this study to achieve complete retention of free glycerol from biodiesel. Response surface methodology was used to optimize process parameters such as average pore size, pressure, and ethanol concentration. At a pore size of 0.2 µm, 3 bar pressure, and 10% wt. ethanol concentrations, 99.8 percent glycerol retention was obtained under optimal conditions. The free glycerol was separated from the biodiesel in compliance with international standards.

Nano-bentonite was prepared from Iraqi bentonite clay by the co-precipitation method and the adsorption technique was used under many factors to determine the adsorption capacity (q) and removal% of arsenic ions (As) from the hospital's wastewater. The optimization process was conducted to choose the optimal parameters for adsorption and removal of arsenic by applying the central composite design (CCD) to form a surface response with three levels and three central points. Three operational factors were optimized of pH (5.5), bentonite dose (100 mg/L), and contact time (5 min), as well as developing the regression quadratic equations to assess the important models for the arsenate adsorbing and removing which dependent on the correlation factor (R2) that was (q = 0.9998) and (removal% = 0.9709), the adsorption isotherm results were fit well with the Langmuir model (R2 = 0.972), and the adsorption kinetics results were perfect with the second model (R2 = 0.951). We conclude that bentonite clay is a good adsorbent that can be used in the processes of removing toxic ions from water.

Aim: The present research work was aimed to formulate fast disintegrating tablets (FDTs) of salbutamol sulphate (SBS) using a combination of a superdisintegrant and a subliming agent, optimize the formulation and evaluate the in vitro performance of the developed FDTs. Materials and Methods: A formulation of SBS FDT was developed using a combination of superdisintegrant - crospovidone and subliming agent - Ammonium Bicarbonate (AB) in which formulation variables, namely levels of crospovidone and Microcrystalline Cellulose (MCC):Mannitol (MNTL) ratio, were evaluated for their effects on the response variables, disintegration time, hardness, friability and wetting time, of the resulting FDTs. By employing Central Composite Design (CCD) methodology, the FDTs were optimized to achieve optimum levels of the formulation factors. Results: The desired optimum condition was obtained at 7.82% crospovidone and 70% of 1.56:1 MCC: MNTL ratio, while maintaining AB at 5% level for aesthetic reasons. Under the optimized conditions, the disintegration time, hardness, friability, and wetting time were 14.57 ± 0.53 sec, 7.17 ± 0.82 kg/cm2, 0.311% and 13.14 ± 0.69 sec, respectively. The experimentally observed responses were found to be in close agreement with the predicted values for the optimized formulation. Moreover, the validity of the obtained optimal point was confirmed by the low magnitude of percent prediction error (< 5%). Conclusion: FDTs of SBS were successfully formulated and optimized using CCD employing a combination of a superdisintegrant and a subliming agent.

In this study, we produced levulinic acid (LA) from green microalgae Scenedesmus obliquus under a methanesulfonic acid (MSA)-mediated conversion. To optimize reaction condition and evaluate their reciprocal interactions of reaction factors, a statistical experimental approach with central composite design was used. By optimizing the reaction conditions, LA was formed at a yield of 40.74% based on total carbohydrate at 180 °C, 12.5% biomass, 1.875 M MSA (0.15 M MSA/1% biomass), and 40 min. The combined severity factor (CSF) evaluation showed that glucose formation matched the non-linear sigmoidal equation with high regression. However, the LA formation was matched to the non-linear model (exponential decay) with high regression. The highest LA was observed at CSF > 3.5. The availability of microalgae as biomass and MSA as a catalyst was proven for producing sugar and platform chemicals.

Trichoderma harzianum S7113 as an efficient fungal isolate for laccase production was identified using the 18S rRNA sequencing. T. harzianum S7113 attained its maximal laccase production level on the 14th day of static incubation at 28 °C and pH 5.0 using the inoculum size of 5 discs (14 mm), according to the one factor per time (OFT) method. The most appropriate carbon, organic and inorganic nitrogen sources to promote maximal laccase synthesis were glucose (15 g/L), beef extract (5 g/L), and ammonium chloride (4 g/L), respectively. Results of Response Surface Methodology (RSM) revealed that glucose, meat extract, and ammonium chloride concentrations of 17.54, 7.17, and 4.36 g/L respectively, at a pH value of 6.74 are the favorite conditions for high titer production. The ANOVA analysis highlighted an excellent match between the actual experimental results and the model predicted laccase production levels. The biodegradation of hydroquinone (HQ) by T. harzianum S7113 laccase was most efficient in the pH range of 5.0 to 6.5. The increase in laccase concentration led to a significant increase in the HQ conversion to get a biodegradation rate of 92 ± 2.6% with a laccase concentration of 0.75 U/mL after 3 h of reaction.

Seaweed is an important global commodity since it is the source of many important products such as carrageenans, agar, alginates, and bioactive compounds. Seaweed processing is an energy intensive process since it involves heating large volumes of seaweeds in alkali solutions at high temperatures for up to six hours. To increase energy efficiency, an ohmic based processing system has been developed but has not been tested thoroughly. Therefore, the objective of this study was to identify optimum processing conditions for extraction of carrageenan from Eucheuma spinosum using ohmic heating technology. The experiment was conducted using Central Composite Design with four variables, i.e. extraction temperature, extraction duration, KOH concentration, and solution to seaweed ratio. Following the extraction process, carrageenan was recovered through precipitation using 90% isoprophyl alcohol solution. Results of experiments indicate that extraction yields varied from 29.6-62.4% dry basis with viscosity and gel strength varied from 259-290 mPa.s and 42.54-70.41 g/cm2 respectively. Statistical analysis indicated that extraction yield can be adequately modeled using the four variables and optimum extraction yield (61.59%), gel strength (53.48 g/cm2), and viscosity (284.51 mPa.s) were achieved at 95 °C extraction temperature, 240 minutes of extraction time, 0.4M KOH concentration, and 45:1 solution to seaweed ratio.

This study designed to optimize the operating parameters of the Fenton process in removing acetic acid from food processing using Response Surface Methodology module in the Design of Expert for sustainable water reuse. Optimum operating conditions needed for the highest removal efficiency of 95.2% and 84.7% for color and chemical oxygen demand respectively were found to be at hydrogen peroxide concentration of 0.004 mol/L, ferrous iron concentration of 0.02 mol/L, initial pH of 3.45, and reaction time of 149.08 min for color. While, chemical oxygen demand had a maximum of around 84.7% removal efficiency that could be obtained at a hydrogen peroxide concentration of 0.014 mol/L, ferrous iron concentration of 0.051 mol/L, initial pH of 2.04, and reaction time of 144.58 min. The results showed that the Fenton process via Response Surface Methodology, at a certain level, may be used as a useful technology for pre- and post-treatment of wastewater from food processing for water scarcity as reclaimed water.

This study is dedicated to exploring the effect of pH, leaching time, ferrous sulfate amount, temperature, as well as their interaction on the dissolution of cobalt by response surface methodology. The ferrous sulfate was used as an effective reducing agent for the dissolution of heterogenite, which constitutes the main cobalt mineral found in Congolese Copperbelt, and the experiments conducted were based on central composite design. Analysis of variance was carried out to study the effects of the individual variable as well as their combined interactive effects on the recovery of cobalt. The optimum process conditions for the cobalt recovery were determined by a desirability function. The results showed that the amount of ferrous sulfate, leaching time, and leaching temperature were statistically significant as independent linear terms. The results also revealed that the interaction of leaching time and the amount of ferrous sulfate has an important effect on cobalt dissolution. The optimal cobalt recovery was 95.79% at the leaching time of 104.48 min, pH of 1.87, amount of ferrous sulfate of 14.9 g, and temperature of 54.8 °C, while the experiment of validation at these optimum conditions gave the cobalt recovery of 93.82%. This testifies on the goodness of the model developed in this work, thus, verifying that the model is suitable and fits the experimental data with a reasonable error.

Tobacco, one of the most significant nonfood crops, is critical to agriculture worldwide. The tobacco processing business creates a significant amount of hazardous tobacco waste containing nicotine, and only a tiny portion of it gets recycled. Nicotine, the primary component of tobacco products such as cigarettes, is an alkaloid and can be used as an insecticide. This research aims to extract nicotine from discarded cigarette butts and utilize it as an insecticide. Extraction, emulsification, and efficiency testing on cabbage aphids are all part of the procedure. The initial extraction tests used a solvent combination of ethanol and methanol in various ratios, with a 3 : 1 ratio yielding the best results. Temperature (30–60°C), extraction length (4–6 hrs), and sodium hydroxide concentration (1–3 M) are the independent variables studied for extraction parameters, and the optimal conditions are determined using Design-Expert, response surface approach central composite design (RSM-CCD). In addition, artificial neural network (ANN) studies with MATLAB were used to accurately forecast extraction yield. The extracted product was evaluated using a gas chromatography–mass spectrometry (GC-MS) and a UV/visible spectrophotometer. The ideal crude extract yield and nicotine content were 17.75 and 3.26%, respectively, at the optimal conditions of temperature 60°C, time 4 hrs, and NaOH concentration 2.83 M with desirability of 0.832. The nicotine extracted was emulsified by combining the crude extract with a combination of palm oil and surfactants. Density, viscosity, pH, flash point, and surface tension of the emulsified concentration were measured and reported as 1.01 ± 0.01 g/ml, 585.33 ± 2.52 mPa s, 9.37 ± 0.03, 87.96 C, and 34.10 mN/m, respectively. On the cabbage aphid, the emulsified concentrated extract performed best at a ratio of 1 : 100 (emulsified concentrated to solvent).

In this study, to increase the content of quercetin in the isolates obtained from the white and red onion scales, in accordance with the zero waste philosophy, using water as an environmentally and healthy friendly extractant, a mathematical model was constructed, based on the Central Composite Design. The suitability of the model for the accurate and quick study of complex relationships was demonstrated by obtaining a statistically insignificant difference in the yield predicted by the model and that determined experimentally under optimal extraction conditions, i.e., 44.14 mg/g (33.57 mg/g) and 45.54 mg/g (33.31 mg/g) for white (red) onion scales, respectively. To present the obtained isolates applicability, their biological activity was assessed in terms of antioxidant activity and antifungal activity against various fungi, showing properties that are sufficient to encourage the use of this material, previously treated as worthless waste, for the production of various functional ingredients, including functional food additives. Moreover, they can be also used to produce safe and effective protectants meeting the GRAS criteria.

open access article A terephthalic acid-modified chitosan−magnetic nanocomposite (Cs−Tp@Fe3O4) was synthesized and characterized. The synthesized Cs−Tp@Fe3O4wasused in a batch process for the adsorptive removal of the acid blue 25 (AB-25) dye inaqueous solutions. The kinetic data were subjected to the pseudo-first-order, pseudo-second-order, Elovich, and intra-particle diffusion models, while the equilibrium datawere evaluated with the Langmuir, Freundlich, Temkin, and Dubinin−Radushkevichisotherm models. The effects of the initial dye concentration, contact time, andadsorbent dosage, as well as their interactions, on the removal efficiency wereinvestigated using the design of experiments based on a central composite design, andthe resultant data were modeled with the response surface methodology (RSM),artificial neural network (ANN), adaptive neuro-fuzzy inference system (ANFIS), andmultiple linear regression (MLR) approaches. The adsorption process followedpseudo-first-order with good agreement between the experimentalQe(exp)andcalculatedQe(cal.)amounts of dye adsorbed, as well as the values of correlation coefficient,R2(0.999) and percentage of sumsquare error, % SSE (0.640). All the investigated adsorption isothermsfitted all models well in the order of Dubinin−Radushkevich> Langmuir > Freundlich > Temkin withR2> 0.9 with the monolayer maximum adsorption capacity of 440.24 mg/g obtained fromthe Langmuir isotherm. The RSM model predicted the maximum removal efficiency at an optimum initial dye concentration of19.11 mg/L, a contact time of 95.3 min, and an adsorbent dosage of 0.18 g. Statistically, the models werefitted in the order of RSM> ANN > ANFIS > MLR. These results indicated that the prepared Cs−Tp@Fe3O4is an efficient adsorbent for the AB-25 dyeremoval with excellent stability for water treatment applications. (8) (PDF) Chitosan–Terephthalic Acid–Magnetic Composite Beads for Effective Removal of the Acid Blue Dye from Aqueous Solutions: Kinetics, Isotherm, and Statistical Modeling. Available from: https://www.researchgate.net/publication/355954648_Chitosan-Terephthalic_Acid-Magnetic_Composite_Beads_for_Effective_Removal_of_the_Acid_Blue_Dye_from_Aqueous_Solutions_Kinetics_Isotherm_and_Statistical_Modeling [accessed Nov 25 2021].

A lactic acid bacteria (LAB) isolated from pickled Chinese cucumber was screened for bacteriocin production. The strain was identified to be Enterococcus faecium HDX-2. Based on the Plackett-Burman (PB) experiment, glucose, Ca2+, and initial pH were found to be the most significant parameters of bacteriocin production. Afterward, effects of the three main parameters on bacteriocin activity were further investigated by central composite design (CCD) and the optimum composition was glucose 22 g/L, Ca2+ 0.6 mM, and initial pH 7.2. Optimum results showed that bacteriocin activity was increased to 1337.60 ± 36.71 AU/mL, 2.23-fold higher than in MRS medium without parameters optimization. The bacteriocin also showed significant antimicrobial activity against Listeria monocytogenes in meat and cheese model system.

Background/Objective: Repeated freezing and thawing results in the structural, compositional, and functional modifications in food materials. The present study was designed to optimize the effect of Freeze-thaw treatment (FTT) on free radical scavenging and linoleic acid reduction potentials of Nelumbo nucifera rhizome starch (NNRS). Methodology: A 4-factorial response-surface central composite design (CCD) based on three levels of each of the four input factors including freezing temperature (FT: -40, -20, and 0°C), freezing time (Ft: 24, 48, and 72 h), thawing time (Tt: 2, 4, and 6 h), and number of freeze-thaw cycles (FTC: 2, 4, and 6) was constructed. The NNRS was treated at different combinations of input variables as selected by CCD. The Freeze-thaw-treated N. nucifera rhizome starch (FTT-NNRS) was analyzed for antioxidant potential. Principle Findings: A statistically significant main effect (p=0.0017-0.0029) of FTT was observed on free radical scavenging and linoleic acid reducing potential (LARP) of NNRS. The 2, 2-diphenylpicrylhydrazyl (DPPH) radical scavenging potential was found to be a linear positive function of FT and Ft while hydroxyl radical scavenging potential showed a linear linear negative response towards FT and linear positive response towards FTC. The LARP also showed a linear positive response towards FT and Tt and quadratic positive response towards FT. Conclusion: FTT significantly affected the free radical scavenging potential and LARP of NNRS that may be attributed to the time-dependent variation in the structure of starch and exposure of some antioxidant residues after repeated freezing and thawing treatments.

This research, aimed to synthesis and functionalize of Fe3O4 magnetic nanoparticles (MNPs) using dialdehyde starch and modifying with arginine amino acid. The resulting MNPs were characterized by Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscope (SEM) and Vibrating sample magnetometer (VSM). Synthesized MNPs were developed for preconcentration and determination of diclofenac in biological samples by UV- Vis Spectrophotometry. A Plackett–Burman experimental design was used to evaluate the influence of effective parameters. Significant parameters were further optimized by Central Composite Design (CCD). Sample volume, pH and salting effect had a main effect on extraction of diclofenac by the proposed method. Under the optimized conditions, the detection limit (3Sb, n = 7) was found to be 0.039 µg ml− 1.The calibration curve showed dynamic linear 0.05-10 µg ml− 1 with correlation coefficients (R2) of 0.987. The enrichment factor was found to be 148. The proposed method showed good results for preconcentration and determination of diclofenac in serum and pharmaceutical samples.

Biosurfactant production by Pseudomonas guguanensis D30 was reported using mineral oil in submerged condition. Twelve medium components were tested at two levels by Plackett-Burman design, among them, mineral oil, yeast extract, peptone, MgSO4, and CaCl2 found significant on the basis of emulsification index. These five significant components were further optimized through central composite design (CCD). The experimental design was successfully used for regression analysis and the significant model suggested the solution of 10% (v/v) mineral oil, 3.0 g/L (w/v) yeast extract and 0.2 g/L (w/v) peptone for 13.14 g/L predicted biosurfactant production. We kept the suggested concentrations of medium components and got 13.34 ± 0.08 g/L biosurfactant production, which is almost double the conventional one-factor-at-a-time production (7.126 ± 0.12 g/L). It reduced the surface tension of the medium up to 28 ± 1.2 mN/m. We found ethyl acetate a suitable solvent for biosurfactant extraction amongst methanol, chloroform, and methanol:chloroform. The partially purified biosurfactant was chemically characterized as lipopeptide by Fourier transform infrared spectroscopy (FT-IR).

In this research, porous adsorbents of hypercrosslinked microporous polymer based on carbazole networks (HCP-CN) were synthesized for Pb(II) elimination from wastewaters. The results demonstrated that the extreme HCP-CN adsorbents utilization in wastewater treatment could remove more than 99.88% of Pb (II) ions. Furthermore, the two consumed adsorbents similarly indicated rapid adsorption kinetics, and it merely took a while to achieve adsorption equilibrium. These characteristics showed that HCP-CN adsorbent was an outstanding candidate for Pb(II) elimination from wastewater. Besides, the thermodynamic characteristics involving Gibbs free energy change (∆G0), entropy change (∆S0), and enthalpy change (∆H0) of the adsorption procedure were evaluated, and the results affirmed that the adsorption process was exothermic and spontaneous. In addition, response surface methodology (RSM) as a statistical investigation was used to optimize adsorption factors to obtain maximum adsorption capacity and investigate the interactive effect of parameters using central composite design (CCD). Optimum conditions obtained by RSM for maximum adsorption capacity of 26.02 mg/g are 35 °C, 40 mg/L, 11, 60 min, and 99.88 for temperature, initial concentration, pH, time, and removal percent, respectively. In the kinetic modeling study, the second-order model was selected as the best model. The values R2 at temperatures 35 °C, 40 °C, and 55 °C are 0.997, 0.9997, and 0.998, respectively. In the isotherm modeling, Hill model with a value R2 of 0.9766 has a superior precision compared to the other isotherm models. Also, the values of ΔH and ΔS at Pb(II) concentration of 60 mg/L are 122.622 kJ/mol and 0.463 kJ/mole K, respectively.

The azo dye removal from polluted water is vital from a sustainable viewpoint. In this study, we investigated the influence of chitosan molecular weight on the adsorptive removal of basic blue 41. For preparing nanocomposite containing medium-molecular weight chitosan (NC(M)), cross-linking of chitosan was done using diethylenetriaminepentaacetic acid, silica-modified magnetite nanoparticles and graphene oxide. Techniques including FT-IR, XRD, FESEM, TGA/DTG, VSM and N2 adsorption/desorption isotherm were applied for characterization of NC(M). The adsorption behavior of synthesized NC(M) was compared with as-prepared adsorbent containing low-molecular weight chitosan (NC(L)) (Asadabadi 2021). The experimental design was carried out using the Central Composite Design. The effect of initial pH, temperature and adsorbent concentration on the percentage of dye removal were examined and the optimum values of variables were determined. Despite NC(M) which had maximum 31% dye removal, NC(L) led to approximately 95% adsorptive removal at optimum conditions. An increase in the monomer number of chitosan caused to reduce hydrophilic property of NC(M), which in turn resulted in a repulsion force between adsorbent and dye. However, H-bonding, coulumbic attraction and pi-stacking interactions contributed in the adsorption mechanism of NC(L). The kinetics study showed that about 30 min necessitated reaching the equilibrium and the rate-limiting steps changed from film diffusion to intra-particle diffusion as time passed. The kinetics data were satisfactorily fitted by the modified pseudo-n-order model. The maximum adsorption capacity of NC(L) was obtained 55.87 mg·g− 1. The modified Langmuir-Freundlich isotherm was the best model to reproduce data. NC(L) was recovered seven times without dramatic changes in its adsorption efficiency.

The work was designed to utilize the integration of microwave assisted extraction preceded by ultrasonic pre-treatment to enhance the extraction yield of essential oil. It called sequential ultrasonic microwave assisted extraction (SUMAE) method. The target plant was Lavandula coronopifolia Poir which has unique therapeutic properties. Comparisons in terms of extraction yield, antioxidant properties, chemical composition, antimicrobial properties, and environmental effects of the proposed method were performed by microwave extraction as a base method. Ultrasonic power, microwave power, and extraction time were selected as independent variables in order to optimize the extraction conditions using response surface methodology (RSM) with the central composite design (CCD). Essential oil yield was considered as the response. The highest yield was equivalent to 1.15% (w/w) which obtained under the following conditions: 150 W of ultrasonic power, 800 W of microwave power, and 40 min of extraction time. The value has increased by about 82% compared to the base method. The chemical composition results of the active ingredients showed that the number of compounds in SUMAE method is much higher than the one in the microwave method. Moreover, according to DPPH and FRAP results, the essential oils extracted by SUMAE method had more antioxidant properties The study of antimicrobial properties showed that the active ingredients obtained from the suggested extraction method have the highest antimicrobial properties. Besides that it is more environmental friendly than microwave-assisted extraction method.

Ultrasound-mechanical stirrer assisted extraction (UMSAE) of extraction yield, total alkaloid content (TAC) and antioxidant (DPPH) activity from Annona muricata leaves were optimized using response surface methodology. Five factors were screened using Plackett-Burman Design to investigate the variables that significantly influence the extraction yield, TAC and DPPH activity, namely solvent concentration, extraction time, ultrasound power, plant material to solvent ratio, and extraction temperature. According to statistical significance analysis, solvent concentration, ultrasound power, plant material to solvent ratio, and extraction temperature were selected for further optimization of the UMSAE extraction process using a Central Composite Design. ANOVA results exhibited that the obtained models were significant at 95 % confidence level. Satisfactory extraction yields (26.38 %) and TAC (39.73 mg AE/g) were obtained with relatively short extraction time under the optimum conditions compared with conventional Soxhlet extraction. The extract prepared under UMSAE displayed excellent DPPH activity (93.15 %). The optimized UMSAE promoted considerable yield increases 1.59-fold the yield extract, 2.32-fold TAC, and 1.19-fold antioxidant activity if compared to the Soxhlet extraction. This study provides the ideal integrated UMSAE settings for the maximum recovery of total alkaloid content with high antioxidant activity from A. muricata for possible utilization of their leaves in food applications.

The present study aimed to determine the optimum extraction conditions of conventional solvent extraction (CSE) and microwave-assisted extraction (MAE) techniques to obtain maximum total phenolic (TPC), total flavonoid (TFC), total anthocyanin (TAC) and antioxidant capacity (AA). Response surface methodology (RSM) and central composite design (CCD) were used to determine optimum points of CSE and MAE. Both two extraction methods, all parameters significantly affected TPC, AA, TFC and TAC (p

This study evaluated the applicability of the adsorption of a widely used organophosphorous pesticide named diazinon, from aqueous using a new composite consisting of nan-TiO2 and polypropylene (Nano-PP/TiO2). The Nano-PP/TiO2 was prepared by wet heat with submerging in an ultrasonic chamber. Extraction and analysis of diazinon were accomplished with dispersive liquid-liquid-microextraction and gas chromatography. By using FTIR, SEM, TEM, and BET technologies, specifications of Nano-PP/TiO2 structure were determined. Adsorption equilibrium and kinetics of diazinon were investigated in a batch reactor and the effects of adsorbent dose, contact time, and initial concentrations of diazinon were assessed. It was found that the two-parameter models arranged the data better than the three-parameter, and the equilibrium data was represented properly by the Langmuir. Additionally, it was identified that adsorption followed the pseudo-second-order kinetic model. To optimize the conditions for maximum adsorption of diazinon, response surface methodology was implemented the effects of factors on the adsorption efficiency were surveyed. The values of optimal initial diazinon concentration, contact time, and mass of Nano-PP/TiO2 were obtained at 10 mg L−1, 32.2 min, and 2.25 g L−1, respectively. Based on the results, the Nano-PP/TiO2 can be used as an effective and efficient adsorbent for the removal of diazinon from aqueous.

The adsorption of Malachite Green (MG) dye was well studied and elucidated from the liquid phase using reduced Graphene Oxide (rGO) nano-adsorbent. The desired levels of the factors were determined to be the amount of adsorbent of 0.2 g/L, pH of 8.5, the concentration of the dye as 100 mg/L and the sonication time of 50 min by Central Composite Design (CCD). The removal of the dye was found to be 95% at the optimum levels of the variables. Furthermore, the removal of the dye was higher at the higher values of the amount of adsorbent and pH. Langmuir and Temkin models were observed significant for rGO-MG dye system. The values of Gibb's free energy, the entropy and the enthalpy were found to be -10.502 KJ/mol, 34.314 KJ/mol and 0.147 KJ/mol.K, respectively. The kinetic data were also found well fitted to pseudo second order kinetics model for the said system. Afterwards, the cost of the process was found to be US$0.654/dm3. Therefore, the adsorption process effectively removed the dye from the simulated aqueous phase using rGO nano-adsorbent.

Biosurfactants are biologically secreted amphiphilic molecules which resemble with the chemical surfactant in function. Compared to the chemical surfactants, they are biodegradable, biocompatible and less toxic. However, commercialization of biosurfactant production is still challenging due to high production and recovery cost, less efficient strain availability, and less knowledge about biosynthetic or metabolic pathways of biosurfactant production. Therefore, the attempt was made to optimize the production parameter for improving the biosurfactant production using Central Composite Design (CCD) from Sphingobacterium thalpophilum DP9. In addition, application of biosurfactant as shampoo ingredient was also studied. Results showed that the biosurfactant production was increased by 4.94 fold when 1% bacterial inoculum was inoculated in Bushnell-Hass medium (pH–11) supplemented with 8 g% sucrose. Biosurfactant was effectively purified by acid precipitation from cell free supernatant. Chromatographic techniques (TLC and HPTLC) and Native–PAGE electrophoresis confirmed glycoprotein nature of the biosurfactant with 85.75 ± 0.05% carbohydrate and 4.58 ± 0.03% protein part. In addition, two fragments of protein (37 kD and 44 kD) were also observed in electrophoretic analysis. According to the ‘blind touch test’ data of volunteer it was noted that the biosurfactant based shampoo showed satisfactory (conditioning) activity compared to commercially available shampoo. Therefore, it was concluded that glycoprotein produced from S. thalpophilum DP9 can be used in cosmetic or personal health products.

PURPOSE: Introducing and developing new kinds of adsorbents are always a significant challenge in water treatments. In this work, for the first time, graphene oxide (GO), nitrogen-doped graphene oxide (ND-GO), highly nitrogen-doped graphene oxide (HND-GO), and 3D high nitrogen-doped graphene oxide (3D-HND-GO) were synthesized and comparatively evaluated in the removal of nitrate content of tap and underground waters. METHODS: The removal of the target analyte was performed through a batch adsorption approach, and the factors influencing its removal efficiency (i.e., initial pH of the sample, primary concentrations of nitrate, amount of adsorbent, and contact time) were evaluated through a central composite design (CCD) and response surface methodology (RSM). RESULTS: Based on the results, 3D-HND-GO showed the highest removal efficiency in comparison with the other mentioned nanoparticles. The nitrate removal using this adsorbent was modeled successfully so that R(2), adjusted R(2), and predicted R(2) values were 0.9717, 0.9508, and 0.9010, respectively. In addition, the optimal removal condition was achieved using the Nelder-Mead non-linear optimization algorithm as follow: the initial concentrations of nitrate (expressed as nitrogen): 15.0 mg/mL, the amount of the adsorbent: 2.0 mg/mL; pH of the sample: 3.0; and the contact time: 20.0 min. Under this optimal condition, the actual removal result (92.5 ± 4.0%) was in good agreement with the expected value (94.8 ± 5.1%). Additional studies were also performed to comprehensibly evaluate the adsorption activity of the adsorbent (e.g., kinetic, isotherm, and desorption parameters). The adsorption isotherm complied with the Langmuir model illustrating the considerable mono-layer adsorption capacities for the target ions with q(m) of 8.7 mg/g. The adsorption process was indicated to obey a pseudo 2nd order kinetic model, with the rate-limiting step for the adsorption phase. CONCLUSIONS: This study revealed which 3D-HND-G leads to improved yield in the nitrate ions elimination, particularly at acidic media, which was related to the enhanced dispersibility and larger surface area. The adsorbent was further successfully used for treating tap and underground water samples. At the present moment, research as grown to modify 3D-HND-G in orders to increase the potentiality for industrial applications. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40201-021-00741-7.

A massive quantity of Elaeis guineensis (oil palm) trunk biomass, containing a significant amount of natural starch, is available in Malaysia as bio-waste because of annual replantation. The efficient extraction of this starch (carbohydrate polymer) would be worthwhile concerning the environmental sustainability and economy through conversion to bio-resources. This study investigated the effectiveness of the bisulphite steeping method for starch synthesis from oil palm trunk (OPT) bio-waste. The central composite design (CCD) of Design-Expert software executed an experimental model design, data analysis, evaluated the impacts of process variables and their interaction through response surface methodology to optimize the bisulphite steeping method for starch synthesis. The developed quadratic models for four factors (strength of sodium bisulphite solution, steeping hour, mixing ratio with the bisulphite solution and ultra-pure water) and one response (%Yield) demonstrated that a significant starch yield (13.54%) is achievable employing 0.74% bisulphite solution, 5.6 steeping hours, for 1.6 and 0.6 mixing ratio with the bisulphite solution and ultra-pure water respectively. Experimental outcomes were consistent with the predicted model, which eventually sustains the significance of this method. Malvern Zetasizer test revealed a bimodal granular distribution for starch, with 7.15µm of hydrodynamic size. Starch morphology was determined by scanning electron microscopy. X-ray diffraction investigation exhibits an A-type model, specifying persistent characteristics, while FTIR confirms the presence of hydroxyl, carboxylic, and phenolic groups like other cereal starches. Implication StatementMalaysia is the 2nd largest palm oil exporter of the world and produced 20.5 million metric tons of crude oil with 2.13 metric tons of palm kernel oil annually. Therefore, a massive quantity of palm oil trunk (OPT) biomass (110 million tons by 2020) is available annually as biowaste during the replanting activities. This huge volume of bio-waste is a severe environmental burden regarding the disposal issue. Modification of bio-wastes into a beneficial form (only 22% currently) would be sustainable for both the environment and the country's economy by diminishing the solid waste dumping challenges.Naturally OPT contains about 20% of lignin, 70% of cellulose, and a significant amount of starch, which is a is a carbohydrate polymer. Efficient extraction of starch from OPT bio-waste could ensure a potential reuse towards sustainable waste management and at the same time various application of starch i.e. as natural coagulant for wastewater and leachate treatment, food source, adhesive for particle boards etc.Even though several studies applied various methods for starch extraction from natural sources rather the current study aims to investigate the effectiveness of the novel bisulfite steeping method for the synthesis of natural starch from the OPT biomass and process optimization by applying the central composite design (CCD), from response surface methodology (RSM). The impacts and interaction of process variables were evaluated by RSM to optimize the starch yield. The developed quadratic model demonstrated that this method could achieve 13.54% starch yield, which is higher than previous studies.Therefore, implementation of this study outcomes will ascertain the reuse of OPT bio-waste reducing waste load from this sector and maximize the natural starch extraction for further implication of numerous economic activities.

In this research, Zn, Ni, and Cu recovery from mobile phone printed circuit boards was investigated. The initial pH and pulp density using Aspergillus niger or Penicillium simplicissimum fungi were optimized to improve the recovery of Zn, Ni, and Cu using a central composite design. Fungi were able to recover 97% of Cu. Often for Ni recovery, A. niger was more effective, but in low pulp densities and low pH, P. simplicissimum was preferred. For recovery of Zn, A. niger is more appropriate at pH lower than 6, but P. simplicissimum outperforms at pH higher than 6. Under the optimum conditions (pulp density of 4 gL−1 and initial pH 10), the respective recovery of Cu, Ni, and Zn was determined as 94%, 100%, and 100% using A. niger as well as 100%, 95%, and 87% using P. simplicissimum. At alkaline conditions, oxalic acid, citric acid, and gluconic acid are the main acids produced by A. niger; the main acid produced by P. simplicissimum is oxalic acid. Similarly, FTIR and chemical characteristics of the metabolites (the organic acid produced) were analyzed under optimal conditions using HPLC. A. niger in alkaline and acidic conditions produces more acids which lead to higher recovery.

The aim of this work is to optimize the supercritical liquefaction process of rapeseeds in order to produce a bio-oil with low viscosity. Reaction parameters, such as reaction temperature, residence time, and solvent to biomass ratio, were studied. Response surface methodology (RSM) based on central composite design (CCD) was used to determine the optimum operating conditions to minimize the bio-oil viscosity. The low bio-oil viscosity of 5.90 mPa.s was obtained at the optimal operating conditions of 280°C, 40 min, and methanol/biomass mass ratio of 5.5/1, at pressure within the batch reactor of 124.59 bars. At these optimal conditions, the bio-oil yield was high and reached around 80wt%, while its heating value was about 38.36MJ/kg. It was proved that the reaction temperature and methanol/biomass ratio were the most influencing parameters on bio-oil viscosity according to the ANOVA results. The predicted values from the RSM model was in good agreement with the experimental results. The GC-MS analysis showed that the bio-oil is mainly composed of methyl esters, which are the main components of biodiesel. This study revealed the complete supercritical transesterification of lipid into alkyl esters resulting in a low amount of triglycerides, monoglycerides, diglycerides, and glycerin, identified by GC-FID. The results will provide useful guidance for predicting other physical properties of bio-oil following a similar methodology to that used in this work. In addition, bio-oil could be used for biodiesel fuel production but after hydrodeoxygenation treatment.

A novel magnetic short-channel mesoporous silica SBA-15 composite adsorbent was prepared by the copolymerization of pyrrole and aniline. The prepared novel nanoadsorbent polypyrrole–polyaniline/CoFe2O4-SBA-15 (PPy-PANI/M-SBA-15) has a significant adsorption effect on heavy metal mercury ions. The batch adsorption experiment was carried out to study the effects of various parameters including solution pH, initial concentration (C0), adsorbent dose (dosage), temperature (T), and contact time on the adsorption effect. The analysis results of the response surface method (RSM) and central composite design (CCD) show that the importance for adsorption factors is pH > C0 > T > dosage, and the maximum capacity of PPy-PANI/M-SBA-15 is 346.2 mg/g under the optimal conditions of pH = 6.7, T = 310 K, C0 = 29.5 mg/L, and a dosage of 0.044 g/L. The pseudo-second-order kinetic model and the Langmuir isotherm model simulate the adsorption behavior of mercury ions. In addition, thermodynamic parameters indicate self-heating and reversible adsorption processes. A covalent bond is formed between the nitrogen-containing functional group and the mercury ions. Excellent magnetic properties and high reproducibility indicate that PPy-PANI/M-SBA-15 has excellent recyclability and environmentally friendly properties and can become a potential heavy metal ion adsorbent in practical applications.

Methanol-to-olefin conversion is one of the most successful approaches to producing light olefins. It has been proved that SAPO-34 is the best catalyst for this process. This molecular-sieve is characterized by high thermal stability, moderate acid sites, and shape selectivity. In this report, SAPO-34 was synthesized using the seed-assisted method. Effects of OSDA and seed on crystallinity and particle size were investigated using Central Composite Design. Samples were characterized by XRD, FE-SEM, FTIR, BET, EDX, and TPD. Results showed that the samples had excellent physicochemical properties. The design of Experiments could predict the results accurately (R2 > 0.9). It was demonstrated that template was the key factor in the seed-assisted synthesis of SAPO-34. Template consumption was reduced by 50%, and it was proved that the synthesis time could be effectively decreased to 3 h due to rapid nucleation. Samples exhibited 100% methanol conversion and up to 90% selectivity toward ethylene and propylene.

Purpose: The present study focuses on a systemic approach to develop liposomal aztreonam as a promising dosage form for inhalation therapy in the treatment of pneumonia and explores the in-vitro antimicrobial and cell uptake efficacy. Methods: Liposomes were prepared by ethanol injection method using the lipids - soya phosphatidylcholine (SP) and cholesterol (CH). A central composite design (CCD) was employed to optimize the lipid composition to evaluate the effect on vesicle size, zeta potential and entrapment efficiency of the formulation. A numerical and graphical optimization was carried out to predict the optimized blend. The optimized formulation was characterized for vesicle size, surface charge, encapsulation, surface morphology, differential scanning calorimetry (DSC), powder X Ray Diffraction (PXRD), thermogravimetric analysis (TGA), in vitro diffusion, accelerated stability studies, antimicrobial studies on Pseudomonas aeruginosa NCIM 2200 and in vitro cell uptake studies. Results: The optimized formulation was found to have a particle size of 144 nm, a surface charge of -35 mV, with satisfactory drug entrapment. The surface morphology study proved the formation of nanosized vesicles. The drug release from liposomal matrix was biphasic in nature. The solid-state study revealed the reason for good encapsulation of drug. The moisture retention capacity was found to be minimum. The anti-microbial study revealed the potential antibacterial activity of the optimized formulation over the pure drug. The formulation was found to be safe on the epithelial cells and showed a marked increase in cellular uptake of aztreonam in a lipid carrier. Conclusion: It can be concluded that the optimized liposomal aztreonam could be considered as a promising approach for the delivery of aztreonam through inhalation.

Objectives In this study, a novel Sterculia foetida and pullulan-based semi-interpenetrating polymer network gastroretentive microsphere formulation was prepared using the emulsion crosslinking method and optimized by central composite design. Materials and methods The effects of the amounts of glutaraldehyde, S. foetida, and pullulan on the percent drug entrapment efficiency (EE), percent mucoadhesion at 12 h, and percent in vitro drug release at 12 h were optimized. The microspheres were characterized using scanning electron microscopy, fourier transform infrared spectroscopy, and differential scanning calorimetry. Results The formulation containing 4% v/v glutaraldehyde, 8.28% w/v pullulan, and 2.14% w/v S. foetida had 88.75±1.18% EE, 80.43±1.2% drug release at 12 h, and 81.73±1.50% mucoadhesion at 12 h, which was considered optimum and was used in an in vivo radiographic study. Conclusion Semi-interpenetrating polymer network microspheres loaded with amoxicillin trihydrate were successfully prepared using S. foetida and pullulan. The prolonged retention of microspheres in the stomach with sustained drug release could effectively act against Helicobacter pylori reservoirs in the stomach and improve the therapeutic effect of amoxicillin trihydrate against H. pylori.

Long-acting solid lipid microparticles of tetracycline hydrochloride (TH) were prepared using solvent-free twin screw hot melt dispersion technique utilizing biocompatible lipids. Design of experiments was employed to assess the formulation and process parameters followed by statistical analysis. Plackett–Burman design generated 12 experiments containing varying ratios of lipids and TH (1:2 to 1:8). Compatibility studies by DSC were conducted on these physical mixtures of drug: lipids to check interactions and obtain an indication of lipids melting range. Microparticles were fabricated and evaluated for flow properties, particle size distribution, surface morphology, drug content, percent entrapment efficiency (PDE), and drug diffusion studies. Impact of critical process parameters on responses like throughput and specific mechanical energy consumption (SMEC) was evaluated using central composite design (CCD). DSC study confirmed compatibility of selected C16 to C18 lipids. Microscopic analysis enabled understanding changes in surface morphology pre- and post-diffusion. Lipid compositions and ratios had shown impact on drug diffusion at 2 h and 72 h. PDE was directly linked to TH: lipid ratio in the formulations. Stability of the microparticles was confirmed by assay and XRD and FTIR analysis on selected formulations. Stearic acid and hydrogenated castor oil revealed significant impact on drug diffusion and micromeritic properties, respectively. Low feed rates and high screw speeds led to increase in SMEC. Morphology of melt agglomerates was controlled by varying the feed rates. Microparticles with anticipated particle size and diffusion profiles were achieved with the outlined process, which were deemed suitable to administer inside periodontal cavities.

The utilization of sugarcane bagasse (SB) in fermentation requires pretreatment processes to render fermentable components available to microorganisms. Pretreatment by using ionic liquids (ILs) is considered promising but the high cost is an impediment in its adoption, therefore, a mixture of IL pretreated and untreated SB was utilized to obtain bacterial multienzyme under solid-state fermentation (SSF). Bacillus aestuarii UE25, a thermophilic strain was utilized for that purpose. Fermentation conditions were optimized by adopting a central composite design. The model showed a good correlation between the predicted and the experimental values for amylase, xylanase, endoglucanase, and β-glucosidase. Volumetric and specific productivity of xylanase (4580 IU ml-1 h-1 , 244.25 IU mg-1 substrate, and 50 IU mg-1 protein) were higher than the other enzymes. Changes in lignin content and reduced cellulose crystallinity due to IL pretreatment, followed by fermentation, were visualized by scanning electron microscopy, Fourier transform infrared spectroscopy, and Nuclear magnetic resonance. The strategy adopted by utilizing a mixture of IL pretreated and untreated SB under SSF proved promising to obtain high titers of different enzymes simultaneously. Since the bacterial strain used is thermophilic, therefore, the multienzyme can find its application in commercial processes which are carried out at high temperatures.

The application of semi-solid fermentation has been able to increase the potential for using cassava pulp, an underused biomass from starch processing (tapioca), as foodstuffs which are reflected in an increase in protein content up to 7.07% and a decrease in cyanide content to less than 10 mg/kg (8.78 mg/kg). Further process optimization is required if the cassava pulp fermentation process is to be carried out on an industrial scale. This research was aimed to obtain the optimal fermentation process parameters to produce cassava pulp flour with optimal characteristics as foodstuffs. Optimization of the fermentation process was carried out using the Response Surface Methodology (RSM) with the Central Composite Design model. There were three optimized factors, namely the concentration of S. cerevisiae (1%-3%), ammonium sulfate concentration (1%-2%), and fermentation time (72-120 hours). The determination of the upper and lower limits was based on preliminary research. The optimal characteristics of fermented cassava pulp flour is obtained in the process parameters: starter concentration 1.67%, ammonium sulphate concentration 1.00%, and fermentation time 77.65 hours. The optimal process parameters will produce fermented cassava pulp flour with a protein content of 6.17%, cyanide content of 8.64 mg/kg, and an odour score of 4.93 (maximum score of 5, like very much) which is very potential to be used as foodstuffs.

The objective of this study was to examine the performance of the proxy electrocoagulation method in removing Cefixime (CFX) from water. This study was performed on a laboratory scale on synthetic samples of the antibiotic CFX in a batch reactor. In this study, the effect of five parameters was investigated, such as initial CFX concentration, Hydrogen peroxide concentration, pH, current intensity and reaction time. The results show that under optimal conditions, Proxy Electrocoagulation Process can remove CFX up to 92.25% with a desirability of 1.0. Central composite design (CCD) proposed a quadratic model for this process. Hydrogen peroxide concentration, solution pH, current density and reaction time, was investigated using a CCD. The adequacy of the model was confirmed using statistical tests such as; F-values of 17.66, p-values of 0.0001 and lack of fit of 0.552 for the model, respectively, R2 = 0.819, R2adj = 0.77, R2pred = 0.66, AP = 19.23. Peroxidation electrocoagulation can be an effective method in removing the antibiotic CFX from water. Of course, more research should be done economically compared to other methods.

A peroxidase-like catalyst of a synergistic inorganic nanocomposite was firstly proposed for the occupational exposure monitoring of H2O2. Nano-zeolite Y (nZY) ion exchange of copper (nZY-Cu) is also used as a peroxidase-like catalyst. In this study, the catalyst component was characterized using X-ray diffraction, BET method, XRF, and scanning electron microscopy. In addition, relative activity was used to show the synergistic peroxidase-like activity of nZY-Cu. Thereafter, the central composite design was applied for the parameter optimization of 3,3′,5,5′-tetramethylbenzidine (TMB) oxidation. However, a method was developed for the TMB-H2O2 reaction using nZY-Cu. The catalytic activity of copper increased in nZY-Cu under the pH of 4.58, with 0.32 mg of catalyst, and TMB concentration of 10.57 μM. Accordingly, a simple and sensitive method was set up for the detection of H2O2 in the air samples, with a linear range of 0.5 to 60 ppm, the detection limit of 0.15 ppm, and a recovery level of 94.13 ± 6.5. The proposed method showed a compatible precision with standard method (OSHAVI-6) according to RSDs.

In this research, activated carbon (AC)-based absorbents modified with NiO and MgO were prepared by wet impregnation method for adsorption of carbon dioxide (CO2). The effect of adding (Ni(NO3)2 6(H2O)) and (Mg(NO3)2 6(H2O)) in 1, 3, 5, and 7 wt% to AC was studied. Raw AC and modified AC were characterized by ultimate analysis, scanning electron microscopy, X-ray diffraction, and surface area. In addition, response surface methodology method was used to optimize the adsorption operation condition. The five-level central composite design was applied to design the experiments for three types of adsorbents (AC, AC/NiO-3, and AC/MgO-3) in the temperature and pressure ranges of 25–80 °C and 2–10 bar, respectively. The results indicated that the adsorption capacity of activated carbon was modified after NiO and MgO loading, especially at higher temperatures, and the optimal concentrations were obtained 3 wt% for both of them. For better evaluation of the adsorbents behavior, experimental data were investigated by isotherm, kinetic, and thermodynamic models. The optimum adsorption capacities were obtained 121.35, 105.17 mg/g for AC/NiO-3 and AC/MgO-3, respectively.

This study probed the selective separation of lanthanum and yttrium in a nitrate medium in the presence of aluminum and calcium impurities using di-(2-ethylhexyl) phosphoric acid (D2EHPA). The factors studied in a central composite design (CCD) included extractant concentration, pH, concentration ratio of total impurities to rare earth elements, and interaction of these three factors. The extraction mechanism and types of extracted metal-containing species were delineated by the slope analysis method. The obtained thermodynamic data showed that lanthanum and yttrium extraction by the D2EHPA extractant was exothermic. The extraction of both rare earth elements was accompanied by an entropy reduction. The negative magnitude of ΔS in yttrium extraction reaction suggests stronger D2EHPA-Y(III) complexation relative to La(III). As entropy decreased and enthalpy increased, the extraction process became unspontaneous. Using the proposed flowsheet, lanthanum and yttrium products with > 90% purity were obtained.

Apricot (Prunus armeniaca L.), which belongs to the genus Prunus, is one of the most commonly commercialized fruits produced in Turkey. Apricot pomace, the most common byproduct of apricot nectar processing, is the press residue of the fruit flesh. Ultrasound assisted extraction (UAE) is known as one of the most efficient techniques for separation of valuable ingredients from raw materials with enhanced extraction yield. In this study, UAE parameters (temperature and time) were optimized by using Response Surface Methodology with a central composite design for maximization of the total phenolic and flavonoid contents as well as the antiradical (DPPH scavenging) activity and extraction yield. Phenolic composition and CUPRAC, ABTS and FRAP values of the extract at the highest extraction yield point was also determined. In the results, the highest phenolic and flavonoid contents, antiradical activity and extraction efficiency were determined as 1.206 mg GAE/g DM, 1.015 mg CE/g DM, 79.85% and 7.86% in apricot pomace samples at 50 °C and 90 min trial points, respectively. HPLC–DAD showed that p-coumaric acid, ferulic acid and rutin were the most abundant phenolics found in the extract. CUPRAC, ABTS and FRAP values of the extract were 30.00, 32.30 and 18.80 mg TE/100 g, respectively. In conclusion, this study provided valuable findings to food industry and other related fields for extraction of valuable bioactive compounds from apricot pomace using UAE as an eco-friendly extraction technique.

In this study, an effective adsorbent was synthesized to remove malachite green (MG), which is one of the toxic dyes. Firstly, single walled carbon nanotube with carboxylated acid (SWCNT-COOH) was functionalized with diethylenetriamine and a new nanocomposite was obtained using nano zinc oxide (ZnO) powder. The effects of pH (3-7), the amount of adsorbent (5-15 mg) and the initial concentration (10-50 mg L-1) of the solution on the adsorption uptake were investigated. The optimal parameters that maximize the adsorption uptake according to the specified working range are found to be 4.63 for pH, 49.94 mg L-1 for initial concentration, 5.25 mg for the adsorbent dose, and the maximum adsorption capacity has been found as 52.26 mg g-1. The excellent fitting of the pseudo-second kinetic model with (R2 = 0.9912) was fitted the experimental data. The Freundlich isotherm model gave a clue about the type of adsorption. Furthermore, thermodynamic results showed that adsorption process was endothermic.

In this study, a response surface methodology (RSM) approach using central composite design (CCD) was investigated to develop a mathematical model and to optimize the effects of pH, adsorbent amount and temperature related to the hexavalent chromium removal by biosorption on peanut shells (PSh). The highest removal percentage of 30.28% was found by the predicted model under the optimum conditions (pH of 2.11, 0.73 g of PSh and 37.2 °C) for a 100 mg/L initial Cr(VI) concentration, which was very near to the experimental value (29.92%). The PSh was characterized by SEM, EDX, FTIR, BET, XRD analyses. Moreover, a Langmuir isotherm fitted well (R2 = 0.992) with the experimental data, and the maximum adsorption capacity was discovered to be 2.48 and 3.49 mg/g respectively at 25 and 45 °C. Kinetic data were well foreseen by pseudo second order. Thermodynamic study depicted that biosorption of Cr(VI) onto PSh was spontaneous and endothermic. Regeneration of the PSh using NaOH showed a loss

Microbial levan has great potential as a functional biopolymer in different fields including foods, feeds, cosmetics, and the pharmaceutical and chemical industries. In this study, a good levan producer bacterial strain of Pseudomonas fluorescens strain ES, isolated from soil in Egypt in a previous study, was used. Levan production by this strain was optimized using Plackett-Burman experimental design (PBD) to screen the critical factors of several process variables and Centered Central Composite Design (CCD) was applied for further estimation of the relationship between the variables and the response as well as optimization of the levels. Plackett-Burman (P-B) design showed a p-value 0.0144 less than 0.05 indicated the significance of the model. Sucrose, potassium dihydrogen phosphate, yeast extract and pH value showed the most significant effect on levan concentration at the values of 89.17, 65.83, 24.17, and 15.83, respectively. The purified levan polymer was characterized using different Physico-chemical methods such as Fourier Transform Infrared Spectrometer (FTIR), Nuclear magnetic resonance (NMR), and High-Performance Liquid Chromatography (HPLC) to determine the main composition and functional groups in the obtained polymer. HPLC results indicated that the polymer purification increased the percentage of fructose residue from 75 up to 89. Furthermore, 1H and 13C NMR spectroscopy analysis showed great matching between the obtained signal for our polymer with that reported in other people’s work. The obtained levan polymer exhibited cytotoxic activity against Human epidermoid Skin carcinoma and Hepatocellular carcinoma with IC50 of 469 and 222.7 µg/ml, respectively. Antioxidant activity was determined using DPPH assay and the percentage of inhibition at 1000 µg/ml was found to be

Crambe abyssinica is a non-edible crop able to adapt to adverse climatic conditions, arising as an alternative feedstock for biodiesel production. With this objective, an eco-friendly route for biodiesel production from crambe oil by enzymatic transesterification was evaluated in order to maximize fatty acid methyl esters content. Response Surface Methodology and central composite design (two factors, three levels, one central point, two replicas) was used to obtain predictive models considering catalyst concentration and methanol:oil molar ratio as independent variables. Since the reaction was monitored overtime, a predictive model considering three independent variables (three factors, three levels) was also obtained. Enzymatic transesterification is a good alternative process to obtain high FAME yield, with 84 ± 5 wt % being obtained after 2 h using a methanol:oil molar ratio 6:1 and 8 wt% of enzyme, a value which predictably can increase to almost 99 wt% after 24 h. The results showed that the methanol:oil molar ratio and the enzyme’s concentration considerably influence the FAME content during enzymatic catalyzed reaction. The polynomial regression models obtained can help to balance the concentration of enzyme and alcohol to improve FAME production and to predict the resulting yield.

This investigation compared the adsorption behavior of humic acid (HA) on cellulose, chitosan and nano zerovalent iron/chitosan (nZVI/chitosan). Results show that nZVI/chitosan is very effective in the adsorption of HA from aqueous media. The feasibility of using nZVI/chitosan as an adsorbent for the simultaneous removal of nitrate and HA from aqueous media was also studied. Structural analyses of the samples were identified by TEM, FT-IR, EDX, XRD and N2 isotherms. The effects of pH, amount of composite, nitrate concentration, HA concentration and contact time and their interactions on responses were explored by central composite design (CCD) and response surface methodology (RSM). The optimal conditions of pH (5.5), adsorbent amount (0.098 g), reaction time (27 min) and initial concentrations (110 mg/L for nitrate and 30 mg/L for HA) were obtained from desirability function. The adsorption properties of the resulting nanocomposite toward nitrate and HA were investigated through kinetic and isotherm adsorption studies. The adsorption kinetics was found to fit the pseudo-second order model. The results obtained indicate that nitrate uptake fitted well with the Langmuir model while the Freundlich isotherm was the best model for describing the multilayer uptake of HA from aqueous solutions. Moreover, nZVI/chitosan nanocomposite illustrates a very high antibacterial activity against pathogen bacteria strains such as Staphylococcus aureus ATCC 25935, ATCC 25923, and Pseudomonas aeruginosa ATCC 27853. The findings reported in this investigation highlight the potential of using nZVI/chitosan as a promising adsorbent for the simultaneous removal of nitrate and HA from aqueous solutions.

The possibility of stabilising a residual soil using lime and polyethylene terephthalate (PET) fibre by employing the central composite design technique in response surface methodology and using th...