Walnut Oil Nanoemulsion: Optimization of the Emulsion Capacity,Cloudiness, Density,and Surface Tension

Response surface methodology (RSM) in conjunction with central composite rotatable design (CCRD) was employed to find out the influence of preparation properties of walnut oil/water nanoemulsion namely ultrasonic time (5–15 minutes), walnut oil content (4–10% w/w) and concentration ratio of Span 80 to Tween 80 (K ₀, 0.55–0.80) on response variables including emulsion capacity, cloudiness, density and surface tension. The calculated regression models with high value of coefficient of determination (0.910–0.973) and insignificant lack of fit test indicated satisfactory agreement of empirical models with experimental observations. The results revealed linear term of walnut oil concentration was the most significant (p < 0.05) parameter on the all responses. The overall optimum region to achieve the ideal characteristics was ultrasonic time of 11.74 minutes, walnut oil content of 4.00% (w/w) and K ₀ of 0.80.     

响应面法对3,5-二硝基水杨酸比色法测定水果中还原糖含量条件的优化

采用3,5-二硝基水杨酸(DNS)比色法测定水果中还原糖的含量,在单因素试验的基础上,采用三因素三水平的响应面分析法(RSM)优化DNS法测定苹果还原糖的最佳条件,同时建立数学模型并验证其可靠性。回归方程失拟项不显著(P=0.133 7),预测值与实际值吻合(R~2=0.957 4);影响DNS法测定还原糖含量的因素主次顺序为:DNS用量﹥反应温度﹥显色时间;DNS法测定还原糖含量的最佳条件为:DNS用量4.0 m L,显色时间5.0 min,反应温度87.0℃,测得还原糖实际浓度为94.66 mg/L,与理论预测值基本相符。按照优化的最佳条件,以苹果、桃、葡萄、哈密瓜、脐橙、菠萝6种代表性水果为对象验证该方法的精密度、重复性和准确度,其标准偏差为0.1%~0.5%,相对标准偏差为2.0%~4.8%,加标回收率为90.6%~104.2%。该方法简便、快速,准确度高,重现性好,适合于苹果及其他水果中还原糖的测定。     

Optimization of Electrocoagulation Process to Eliminate CODMn in Micro-Polluted Surface Water Using Response Surface Method

To treat micro-polluted surface water with a better electrocoagulation (EC) process, a response surface method (RSM) was employed to optimize the process parameters. First, the main factor that affected the COD_Mn removal efficiency in the EC process was determined in single-factor experiments. Then, a quadratic regression model was generated using a RSM. The refined EC operating conditions were a current density of 1.57 mA · cm^?2, an initial pH of 7.5, and an operation time of 32 minutes, which maximized the COD_Mn removal efficiency at 60.56%. Finally, the results of a verification test results corresponded with the calculated values, which indicated that the regression model was accurate and reliable.     

Optimization of Fluoride Adsorption on Acid Modified Bentonite Clay Using Fixed-Bed Column by Response Surface Method

Using small-scale batch tests, various researchers investigated the adsorptive removal of fluoride using low-cost clay minerals, such as Bentonite. In this study, Column adsorption studies were used to investigate the removal of fluoride from aqueous solution using acid-treated Bentonite (ATB). The effects of initial fluoride concentration, flow rates, and bed depth on fluoride removal efficiency (R) and adsorption capability (qe) in continuous settings were investigated, and the optimal operating condition was determined using central composite design (CCD). The model’s suitability was determined by examining the relationship between experimental and expected response values. The analysis of variance was used to determine the importance of independent variables and their interactions. The optimal values were determined as the initial concentration of 5.51 mg/L, volumetric flow rate of 17.2 mL/min and adsorbent packed-bed depth of 8.88 cm, with % removal of 100, adsorptive capacity of 2.46 mg/g and desirability of 1.0. This output reveals that an acid activation of Bentonite has made the adsorbent successful for field application.     

Ultrasound Plus Vacuum-System-Assisted Biocatalytic Synthesis of Octyl Cinnamate and Response Surface Methodology Optimization

Cinnamic acid is one of the phenolic compounds that is isolated from cinnamon, or other natural plants, and has a wide range of physiological activities. However, the application of cinnamic acid is limited due to its poor solubility and low oral bioavailability. In this study, the feasibility of producing octyl cinnamate by ultrasonic assistance, combined with a rotary evaporation under vacuum, was studied using methyl cinnamate and octanol as the starting materials. A Box–Behnken design (BBD) was employed to evaluate the effects of the operation parameters, including reaction temperature (55–75 °C), reaction time (4–12 h), and ultrasonic power (90–150 W) on the production of octyl cinnamate. Meanwhile, the synthesis process was further optimized by the modeling response surface methodology (RSM). The data indicated that octyl cinnamate was efficiently synthesized from methyl cinnamate and octanol using the ultrasound plus vacuum system; further, this system was superior to the conventional method. According to the RSM model for the actual experiments, a reaction temperature of 74.6 °C, a reaction time of 11.1 h, and an ultrasound power of 150 W were determined to be the best conditions for the maximum molar conversion of octyl cinnamate (93.8%). In conclusion, the highly efficient synthesis of octyl cinnamate by a rotary evaporator with an ultrasound plus vacuum system was achieved via RSM optimization.     

Preparation of Water-in-Diesel Fuel Nanoemulsions Using High-Energy Emulsification Method and a Study of Some of Their Surface Active Properties

In this work, formations of water-in-diesel fuel nanoemulsions using water/mixed nonionic surfactant/diesel fuel system has been studied. The high-energy emulsification method was used to form three emulsions using different water contents: 5, 10, and 14% (v/v) namely; E1, E2, and E3, respectively. These nanoemulsions were stabilized with emulsifiers having different hydrophilic lipophilic balance (HLB), namely, Span 80 (HLB = 4.3), Emarol 85 (HLB = 11), and their mixture (SE) with HLB = 10. The effect of water on the droplet size formation has been investigated. The interfacial tension and thermodynamic properties of the individual and emulsifiers blends have been studied. The interfacial tension (γ) measurements at 30°C were used to determine the critical micelle concentration (CMC) and surface active properties of these emulsifiers. The water droplet sizes were measured by dynamic light scattering (DLS). From the obtained data, it was found that mean sizes between 19.3 and 39 nm were obtained depending on the water content and concentration of blend emulsifiers (SE). Also, the results show that the interfacial tension (γ) gives minimum value (10.85 mN/m) for SE comparing with individual emulsifier (17.13 and 12.77 mN/m) for Span 80 and Emarol 85, respectively. The visual inspection by transmission electron microscopy showed that the obtained results support the data obtained by dynamic light scattering.     

Preparation of Carvedilol Nanoparticles by Emulsification Method and Optimization of Drug Release: Surface Response Design Versus Genetic Algorithm

The objectives of this research were the production of Eudragit nanoparticles of carvedilol, an anti-hypertension drug, for enhancement of its absorption and optimization of drug release. Nanoparticles were prepared by emulsification-solvent evaporation or diffusion methods. The statistical surface response design, based on the Box-Behnken model, was applied to evaluate the effect of four variables, each in two levels, on specifications of nanoparticles. An intelligent modeling system was established according to genetic algorithm to predict drug release from the nanoparticles. The neural network-genetic algorithm model showed a more precise method than surface response design in the prediction of the release properties of carvedilol from Eudragit nanoparticles.     

Characterization of Biodegradable Nanocomposite Films Prepared with Glutelin from Jatropha curcas L. by Response Surface Methodology and Infrared Spectroscopy

The water vapor permeability (WVP) and hardness of biodegradable nanocomposite films based on glutelin from Jatropha curcas L. were determined and the results were analyzed by response surface methodology (RSM). The effects of independent variables constituted by the plasticizer (glycerol), nanofiller (cloisite), and pH on the physical parameters were evaluated. The regression models obtained for each physical property adequately described the measurements used in the experimental design, with regression coefficients of 0.9513 and 0.9421 for WVP and hardness. The regression coefficients show that pH has the most significant effect on the WVP, whereas the cloisite content has the largest influence on the hardness of the nanocomposite film. Fourier transform infrared spectroscopy provided confirmation of the results obtained by RSM. Corroboration that the gluteline structure is in a similar form as the WVP and primarily influenced by pH was obtained using conventional and second derivative infrared spectra. However, the hardness of the film primarily depends on the cloisite content. This methodology may be useful for the design and elaboration of nanocomposite films based on J. curcas L. with specific barrier and mechanical properties.     

低场核磁共振结合化学计量学方法快速检测掺假核桃油

以掺假核桃油样品为低场核磁共振检测对象,利用主成分分析法(PCA)和偏最小二乘回归法(PLSR)分析处理Carr-Purcell-Meiboom-Gill(CPMG)序列的核磁共振弛豫数据,旨在探求一种能快速检测核桃油品质的新方法。对几种常见掺假形式(掺入大豆油、玉米油、葵花油)的核桃油样品和纯核桃油样品进行检测和评价。实验结果表明:纯核桃油和掺入不同种类食用油的掺假核桃油在主成分得分图上可以得到很好的区分,且掺假样品随掺假比例在图中呈规律性分布;采用PLSR法对CPMG数据和实际掺假率进行回归,可实现对核桃油掺假水平的准确定量测定。方法快速、无损、准确,在食用油制品的品质控制及评价方面具有很大的应用潜力。     

Optimization of Microwave-Assisted Extraction (MAE) for the Isolation of Antioxidants from Basil (Ocimum basilicum L.) by Response Surface Methodology (RSM)

Abstract

The recovery of antioxidants from basil (Ocimum basilicum L.) was modeled with the aid of response surface methodology (RSM) using microwave-assisted extraction (MAE). Face-centered central design (FCCD) was employed to optimize the MAE operational parameters including the extraction time (1 to 7?min), extraction temperature (30 to 120?°C), solid-to-solvent ratio (0.1 to 0.4), and solvent concentration (20 to 80% ethanol, v/v), and to obtain the best possible combinations of these parameters for a high antioxidant yield from basil. The total antioxidant capacity (TAC) was expressed in trolox (TR) equivalents per gram of dried sample (DS). Three of the operational parameters (temperature, extraction time and solvent concentration) were shown to have significant effect on the extraction efficiency of antioxidants in basil extracts (p?<?0.05). The solvent concentration was shown to be the most significant factor on antioxidant yield obtained by MAE. There was a close relationship between experimental and predicted values using the proposed method. This optimized MAE method shows an application potential for the efficient extraction of antioxidants from basil in the food and pharmaceutical industries.     

Optimization of Taxol Extraction Process Using Response Surface Methodology and Investigation of Temporal and Spatial Distribution of Taxol in Taxus mairei

Taxus mairei is an important source for industrial extraction of taxol in China. However, the standard and steps of extraction are currently not uniform, which seriously affects the taxol yield. In the present study, the influence of four factors (methanol concentration, solid-liquid ratio, ultrasonic extraction temperature, and ultrasonic extraction time) on the taxol yield was successively explored in T. mairei. A response surface methodology (RSM) was used to optimize the extraction process based on the single-factor experiments above. The optimal conditions were as follows: methanol concentration was 90%, solid-liquid ratio was 1:15 (g/mL), ultrasonic extraction temperature was 40 °C and ultrasonic extraction time was 60 min. Moreover, the twigs and needles from T. mairei with different tree ages were treated by the optimum extraction process, which further revealed temporal and spatial distribution of taxol in the reproducible tissues. Interestingly, the taxol content was relatively higher in needles of T. ‘Jinxishan’ (a cultivar from T. mairei with yellow aril, FY), but was less in FY twigs. The accumulation of taxol in twigs and leaves of females (with red aril, FR) was significantly higher than that of males (M); however, the content showed a decreasing trend with the increasing tree ages. Therefore, it is suitable to increase the proportion of female trees especially the FY leaves as raw materials for the industrial production of taxol from T. mairei, and the tree ages should be better controlled at 3–7 years.     

Effects of Orange Leaves Extraction Conditions on Antioxidant and Phenolic Content: Optimization Using Response Surface Methodology

In the last few years, bioactive components or their extraction techniques are gaining special interest in scientific areas. In this framework, orange leaves were used for preparation of extracts with high content of biologically active compounds. To optimize the extraction process, three levels and three variables of Box–Behnken design with response surface methodology were applied. Investigated responses were the total phenolic content (TPC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, cupric ion reducing antioxidant capacity (CUPRAC), and ferric reducing antioxidant power (FRAP). Independent variables were methanol concentration (10–90%), temperature (20–60°C), and extraction time (60–180?min). Experimentally obtained results were fit into a second-order polynomial model with multiple regression. Analysis of variance was used to estimate model fitness and determine optimal conditions for processing. Estimated optimal conditions were 90% methanolic solution, 60°C and 180?min using these parameters; the predicted values of investigated responses were 43.19?mg GAE/g (GAE: gallic acid equivalents), 43.04?mg TE/g (TE: trolox equivalents), 139.34 and 93.76?mg TE/g for TPC, DPPH, CUPRAC, and FRAP, respectively. The obtained optimal conditions could be considered as an alternative strategy for developing novel functional products.     

Optimization of Ultrasound-Assisted Extraction of Polyphenols from Ilex latifolia Using Response Surface Methodology and Evaluation of Their Antioxidant Activity

The polyphenolic extract of Ilex latifolia (PEIL) exhibits a variety of biological activities. An evaluation of the parameters influencing the ultrasonic extraction process and the assessment of PEIL antioxidant activity are presented herein. Response surface methodology (RSM) was used to optimize the experimental conditions for the polyphenols ultrasonic-assisted extraction (UAE) from the leaves of Ilex latifolia. We identified the following optimal conditions of PEIL: ethanol concentration of 53%, extraction temperature of 60 °C, extraction time of 26 min and liquid–solid ratio of 60 mL/g. Using these parameters, the UAE had a yield of 35.77 ± 0.26 mg GAE/g, similar to the value we predicted using RSM (35.864 mg GAE/g). The antioxidant activity of PEIL was assessed in vitro, using various assays, as well as in vivo. We tested the effects of various doses of PEIL on D-galactose induced aging. Vitamin C (Vc) was used as positive control. After 21 days of administration, we measured superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities, malondialdehyde (MDA) levels in mouse serum and liver tissue. The results demonstrated that the PEIL exhibits potent radical scavenging activity against 1,1-diphenyl-2-picrythydrazyl (DPPH∙), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS⁺), and hydroxyl (∙OH) radicals. The serum concentrations of SOD and GSH-Px were higher, and MDA levels were lower, in the medium- and high-dose PEIL-treated groups than those in the aging group (p < 0.01), and the activity of MDA was lower than those of the model group (p < 0.01). The liver concentrations of SOD and GSH-Px were higher (p < 0.05), and MDA levels were lower, in the medium- and high-dose PEIL-treated groups than those in the aging control group (p < 0.01). These results suggest that optimizing the conditions of UAE using RSM could significantly increase the yield of PEIL extraction. PEIL possesses strong antioxidant activity and use as a medicine or functional food could be further investigated.     

Optimization of Maceration Conditions for Improving the Extraction of Phenolic Compounds and Antioxidant Effects of Momordica Charantia L. Leaves Through Response Surface Methodology (RSM) and Artificial Neural Networks (ANNs)

The main goals of this research were the chemical and biological characterization of the bitter melon (Momordica charantia) isolate obtained by traditional (maceration) extraction, as well as optimization of this process using response surface methodology (RSM) and artificial neural networks (ANNs). Experiments were performed using Box–Behnken experimental design on three levels and three variables: extraction temperature (20?°C, 40?°C, and 60?°C), solvent concentration (30%, 50%, and 70%) and extraction time (30, 60, and 90?min). The measurements consisted of 15 randomized runs with 3 replicates in a central point. The antioxidant activity of obtained extracts was determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH), cupric ion reducing antioxidant capacity (CUPRAC) and ferric reducing antioxidant power (FRAP) assays while chemical characterization was done in terms of the total phenolic content (TPC). The methodology shows positive influence of solvent concentration on all four observed outputs, while temperature showed a negative impact. RSM showed that the optimal extraction conditions were 20?°C, 70% methanol, and an extraction time of 52.2?min. Under these conditions, the TPCs were 20.66 milligrams of gallic acid equivalents (mg GAE/g extract), DPPH 30.22 milligrams of trolox equivalents (mg TE/g extract), CUPRAC 67.78 milligrams of trolox equivalents (mg TE/g extract), and FRAP 45.48 milligrams of trolox equivalents (mg TE/g extract). The neural network coupled with genetic algorithms (ANN-GA) was also used to optimize the conditions for each of the outputs separately. It is anticipated that results reported herein will establish baseline data and also demonstrate that that the present model can be applied in the food and pharmaceutical industries.     

Optimization of Fiber-Water Dispersion Process Using Box-Behnken Design of Experiments Coupled with Response Surface Methodology of Analysis

In this work, the fiber-water dispersion process with reference to the wet-lay technology was optimized in order to improve the uniformity of the wet-laid webs by using Box-Behnken design of experiments coupled with response surface methodology of analysis. A series of wet-laid webs were prepared by using cotton fibers of 7 mm cut length and 5.6 micronaire linear density and employing different combinations of three process variables of interest namely stirring rate, dispersion time, and surfactant concentration. The resulting webs were tested for their area-based uniformity by means of quadrat analysis. The response surface model was found to be statistically significant at a P value as low as 0.0213. The experimental results were found to be in good agreement with the model results. The single effect of surfactant concentration, interaction effect of surfactant concentration and stirring rate, and quadratic effect of dispersion time were found to be statistically significant at 0.05 level of significance. The optimum level of coefficient of variation of the area occupied by the fibers in the web was predicted as 10.50% at stirring rate of 250 rpm, dispersion time of 5 minutes, and surfactant concentration of 0.10 and this was experimentally observed as 11.02%.     

响应曲面法在乙酰化-顶空固相微萃取检测水中酚类的条件优化应用

建立了水中酚类化合物的原位乙酰化-顶空固相微萃取/气相色谱-质谱联用测定方法,并采用响应曲面法中的中心组合设计对实验进行过程优化,选取经单因子实验证实为非单调变化的连续变量,即衍生化试剂(乙酸酐)、衍生化助剂(Na2HPO4)以及反应/萃取温度3个重要因子,以标准化后的峰面积(应变量,代表相对萃取效率)为响应因子,经后...     

Optimization of Microwave-Assisted Michael Addition Reaction Catalyzed by L-Proline in Ionic Liquid Medium Using Response Surface Methodology

Michael addition reactions of aldehyde to β-nitrostyrene catalyzed by L-proline were investigated by using controlled, monomode microwave-assisted technique in a closed vessel system. Ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([bmim]NTf₂) was used as the reaction medium to replace the commonly used volatile organic solvents and as a good absorbing solvent during Michael reaction under the influence of microwave irradiation. The Michael product is clean and generates good yields in short reaction times with moderate results on enantioselectivity (ee). In this work, optimization of proline-catalyzed Michael reaction was carried out using response surface methodology (RSM) based on a three-factor-three-level central composite design (CCD). Various reaction parameters including catalyst loading (5–30 mol%), reaction time (5–40 min), and substrate (2–5 equivalent ratio) were investigated. A high Michael yield (96.5%) with 36.9 ee% was obtained at the optimum conditions of 10.0 mol% catalyst loading, 5.0 min reaction time, and 2.0 substrate equivalent ratio.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]     

Optimization of UHMWPE/graphene nanocomposite preparation by single‐supported Ziegler‐Natta catalytic system via RSM

In this study, the preparation of ultra‐high molecular weight polyethylene/graphene nanocomposite was carried out using single‐supported Ziegler‐Natta catalyst, and the operational conditions were optimized via response surface methodology. For this purpose, the effect of 3 parameters, monomer pressure, temperature, and molar ratio of [Al] respect to [Ti] on the catalyst productivity and molecular weight of the synthesized nanocomposite polymer, was investigated using the Box‐Behnken experimental design at 3 levels. Monomer pressure, temperature, and molar ratio of [Al] respect to [Ti] were considered as independent variables and catalyst productivity and molecular weight as dependent variables. The highest catalyst productivity and molecular weight were equal to 923 (grPE/mmolTi.h) and 2.04 (million gr/mol), respectively, which were obtained under optimal reaction conditions: temperature of 60°C, pressure of 8 bar, and molar ratio of 185. Finally, in order to investigate the morphology and nanoparticle dispersion in polymer matrix, scanning electron microscope and X‐ray diffraction were used. The results indicate the homogenous dispersion of graphene nanoparticles in polymer matrix.     

表面响应曲面法优化微生物中聚β-羟基丁酸酯提取条件的研究

利用表面响应曲面法(RSM)优化次氯酸钠/氯仿混合溶液提取微生物体内聚β-羟基丁酸酯(PHB)的过程,选取了次氯酸钠的百分含量、反应时间、反应温度以及混合液中次氯酸钠与氯仿不同比例为因子,以PHB/MLSS为响应因子。实验结果表明提取的最佳条件是NaClO为13%、反应温度为45℃、反应时间为2.8h,NaClO∶CHCl3(V/V)为1.3。利用最佳操作条件,提取出来的产量可以提高25%。     

Ultrasound-Assisted Extraction of Carotenoids from Carrot Pomace and Their Optimization through Response Surface Methodology

Ultrasound-assisted extraction (UAE) was used to extract carotenoids from the carrot pomace. To investigate the effect of independent variables on the UAE, the response surface methodology (RSM) with central-composite design (CCD) was employed. The study was conducted with three independent variables including extraction time (min), temperature (°C), and ethanol concentration (%). The results showed that the optimal conditions for UAE were achieved with an extraction time of 17 min, temperature of 32 °C, and ethanol concentration of 51% of total carotenoids (31.82 ± 0.55); extraction time of 16 min, temperature of 29 °C, and ethanol concentration of 59% for a combination of β-carotene (14.89 ± 0.40), lutein (5.77 ± 0.19), and lycopene (2.65 ± 0.12). The non-significant (p > 0.05) correlation under optimal extraction conditions between predicted and experimental values suggested that UAE is the more productive process than conventional techniques for the extraction of carotenoids from the carrot pomace.