Optimization of Extraction Process of Clerodendrum philippinum Schauer var. simplex Mlodenke Total Flavonoids(CPTF) by Central Composite Design-Response Surface Methodology

[Objectives] The research aimed to optimize extraction process of Clerodendrum philippinum Schauer var. simplex Mlodenke total flavonoids( CPTF),and provide reference for its development and utilization. [Methods] Based on single-factor test,ethanol concentration,extraction temperature and extraction time were taken as independent variables,and total flavonoids yield was taken as dependent variable. The test was conducted according to central composite design principle. Multivariate linear regression and binomial equation fitting of the result were conducted,and extraction process of CPTF was optimized by using response surface methodology. [Results]The optimal extraction process of CPTF was as below: ethanol concentration 54. 76%,extraction temperature 83. 92℃,extraction time 102. 64 min,solid-liquid ratio 1:20,extraction for twice. [Conclusions] The extraction process of CPTF by central composite design-response surface methodology was simple and feasible,with reliable prediction result,which was suitable for industrial production.

Optimization of Extraction Process of Total Flavonoids from Akebia trifoliata (Thunb.) Koidz. by Central Composite Design-Response Surface Methodology

[Objectives]To optimize extraction process of total flavonoids from Akebia trifoliata( Thunb.) Koidz.,so as to provide references for development and use of Akebia trifoliata( Thunb.) Koidz. [Methods]The extraction rate of total flavonoids of Akebia trifoliata( Thunb.)Koidz. was taken as observation indicator. On the basis of single factor experiment,central composite design( CCD) was used to evaluate the effects of the extraction temperature,extraction time,and ethanol concentration on the extraction process. Multiple linear regression and binomial fitting were used,and response surface methodology( RSM) was used to select the optimum extraction process. [Results] The optimum extraction process conditions for total flavonoids of Akebia trifoliata( Thunb.) Koidz. was extraction temperature: 83. 92 ℃; extraction time:96. 47 min; ethanol concentration: 63. 92%; extraction times: two times; solid to liquid ratio: 1 ∶ 20; extraction rate of total flavonoids:4. 55%. [Conclusions] The central composite design-response surface methodology( CCD-RSM) is simple,convenient,and feasible for extraction of total flavonoids from Akebia trifoliata( Thunb.) Koidz.,and the prediction results are reliable.

Application of response surface methodology and central composite rotatable design for modeling the influence of some operating variables of the lab scale thickener performance

This study discussed the application of response surface methodology(RSM)and central composite rotatable design(CCRD)for modeling and optimization of the influence of some operating variables on the performance of a lab scale thickener for dewatering of tailing in the flotation circuit.Four thickener operating variables,namely feed flowrate,solid percent,flocculant dosage and feedwell height were changed during the tests based on CCRD.The ranges of values of the thickener variables used in the design were a feed flowrate of 9–21 L/min,solid percent of 8%–20%,flocculant dosage of 1.25–4.25 g/t and feedwell height of 16–26 cm.A total of 30 thickening tests were conducted using lab scale thickener on flotation tailing obtained from the Sarcheshmeh copper mine,Iran.The underflow solid percent and bed height were expressed as functions of four operating parameters of thickener.Predicted values were found to be in good agreement with experimental values(R2values of 0.992 and 0.997 for underflow solid percent and bed height,respectively).This study has shown that the RSM and CCRD could effciently be applied for the modeling of thickener for dewatering of flotation tailing.

Improvement of xylanase production by Aspergillus niger XY-1 using response surface methodology for optimizing the medium composition

Objective: To study the optimal medium composition for xylanase production by Aspergillus niger XY-1 in solid-state fermentation (SSF). Methods: Statistical methodology including the Plackett-Burman design (PBD) and the central composite design (CCD) was employed to investigate the individual crucial component of the medium that significantly affected the enzyme yield. Results: Firstly, NaNO3, yeast extract, urea, Na2CO3, MgSO4, peptone and (NH4)2SO4 were screened as the significant factors positively affecting the xylanase production by PBD. Secondly, by valuating the nitrogen sources effect, urea was proved to be the most effective and economic nitrogen source for xylanase production and used for further optimization. Finally, the CCD and response surface methodology (RSM) were applied to determine the optimal concentration of each sig-nificant variable, which included urea, Na2CO3 and MgSO4. Subsequently a second-order polynomial was determined by multiple regression analysis. The optimum values of the critical components for maximum xylanase production were obtained as follows: x1 (urea)=0.163 (41.63 g/L), x2 (Na2CO3)=?1.68 (2.64 g/L), x3 (MgSO4)=1.338 (10.68 g/L) and the predicted xylanase value was 14374.6 U/g dry substrate. Using the optimized condition, xylanase production by Aspergillus niger XY-1 after 48 h fermentation reached 14637 U/g dry substrate with wheat bran in the shake flask. Conclusion: By using PBD and CCD, we obtained the optimal composition for xylanase production by Aspergillus niger XY-1 in SSF, and the results of no additional expensive medium and shortened fermentation time for higher xylanase production show the potential for industrial utilization.

Optimization of medium components using response surface methodology (RSM) for mycelium biomass and exopolysaccharide production by <i>Lentinus squarrosulus</i>

The interaction between sucrose, yeast extract and initial pH was investigated to optimize critical medium components for mycelium biomass and production of exopolysaccharide (EPS) of Lentinus squarrosulus using Response Surface Methodology (RSM). A central composite design (CCD) was applied and a polynomial regression model with quadratic term was used to analyse the experimental data using analysis of variance (ANOVA). ANOVA analysis showed that the model was very significant (p Lentinus squarrosulus are as follows: sucrose concentration 114.61 g/L, yeast extract 1.62 g/L and initial pH of 5.81;sucrose concentration 115.8 g/L, yeast extract of 3.39 g/L and initial pH of 6.44 respectively.

Enhacement of the Viability of <i>Lactobacillus</i><i>plantarum</i>during the Preservation and Storage Process Based on the Response Surface Methodology

Objective: The Response Surface Methodology (RSM) is a commonly used system to optimize cell viability of probiotic strains when they are subjected to different preservation and storage processes. Methods and Results: To determine the optimal levels of incorporation of several cry oprotectants (skim milk, sucrose and trehalose) in the freeze-drying process of Lactobacillus plantarum, a range of experiments based on a Rotational Central Composite design (CCD) were conducted. The results were adjusted to a quadratic model, resulting in the presence of interaction between the different variables. Solving a regression equation, we obtained the optimum concentrations of cryoprotective agents: 24.06% milk powder, 6.22% sucrose, 5.63% trehalose. To visualize the interactions between the three variables involved in the study, Design Expert? software was used. Conclusions: The analysis reveals that while trehalose has a direct effect on the viability of L. plantarum, skim milk and sucrose exert quadratic effects. There are also interactions between cryoprotectants, which emphasize the synergies produced between milk and sucrose and between sucrose and trehalose, which allows maintaining the viability of L. plantarum. Significance and Impact of the Study: The addition of new oligosaccharides as trehalose in premixtures for functional feed can maintain the viability of L. plantarum during longer periods of time, ensuring the proper administration of probiotics to their destinations.

Optimization of Dielectric Barrier Discharge Process for Decolorization of Reactive Blue 19 by Means of Response Surface Methodology

The decolorization of reactive blue 19(RB-19)as a model dye from aqueous solutions has been studied by means of the dielectric barrier discharge(DBD)process.The independent parameters of input power,initial dye concentration and initial pH value were evaluated respectively.Experimental data were optimized by means of a 33 factorial design and response surface methodology(RSM).The dye was quickly removed during the treatment,yielding 96.9%of decolorization efficiency under optimized conditions.Therefore,the total organic carbon(TOC)and chemical oxygen demand(CODcr)results indicated that only the chromophore was destroyed rather than completed oxidation.This was confirmed with UV-vis and tertiary butanol assessments during the DBD treatment.

Optimal Evaluation of Coag-Flocculation Factors for Alum-Brewery Effluent System by Response Surface Methodology

This work investigates coag-flocculation optimization treatment of alum-brewery effluent system via response surface methodology (RSM). To minimize suspended and dissolved particles (SDP), experiments were carried out using nephelometric jar test and 23-factorial design with three star-points, six-center-points and two replications. A central composite design, which is the standard design of RSM, was used to evaluate the effects and interactions of three major factors (coagulation pH, coagulant dosage, settling time) on the treatment efficiency. Multivariable quadratic model developed for the response studied indicates the optimum conditions to be 9, 500mg/l and 20minutes for coagulation pH, coagulant dosage and settling time, respectively. At optimum, the SDP was reduced from 10831.490mg/l to 801.451mg/l, representing 92.601% removal efficiency. RSM has demonstrated to be appropriate approach for the optimization of the coag-flocculation process by statistical evaluation.

Optimization of the Impeller Geometry for an Automotive Torque Converter Using Response Surface Methodology and Desirability Function

Response surface methodology (RSM) based on desirability function approach (DFA) is applied to obtain an optimal design of the impeller geometry for an automotive torque converter. The relative importance of six design parameters including impeller blade number, blade thickness, bias angle, scroll angle, inlet angle and exit angle is investigated using orthogonal design approach. The impeller inlet angle, exit angle and bias angle are found to exert the greatest influence on the overall performance of a torque converter, with two flow area factors being considered, namely 17% and 20%. Then, RSM together with central composite design (CCD) method is used to in-depth evaluate the interaction effect of the three key parameters on converter performance. The results demonstrate that impeller exit angle has the strongest impact on peak efficiency, with larger angles yielding the most favorable results. The stall torque ratio maximization is attainable with the increase of impeller bias angle and inlet angle together with smaller exit angle. In the end, an optimized design for the impeller geometry is obtained with stall torque ratio and peak efficiency increased by 1.62% and 1.1%, respectively. The new optimization method can be used as a reference for performance enhancement in the design process of impeller geometry for an automotive torque converter.

Central Composite Design响应面法优化厚裂凤仙花总黄酮提取工艺研究

为厚裂凤仙花中总黄酮资源的开发利用,本文采用单因素与星点-效应面法相结合的方式,考察提取溶剂浓度、料液比、提取时间、提取次数对厚裂凤仙花中总黄酮提取率的影响。优选出厚裂凤仙花总黄酮最佳提取方法为:甲醇体积分数80%,料液比为1︰64,提取时间为50 min;提次数为3次;验证实验结果表明,总黄酮平均提取率为5.51 mg/g,与实验模型RSD值为0.79%。建立的模型与实际方案有较高拟合度,可作为苗药厚裂凤仙花总黄酮提取工艺参数。

星点设计-效应面法优化白及多糖pH-离子敏感原位凝胶的处方

目的优化白及多糖pH-离子敏感原位凝胶的处方。方法以去乙酰结冷胶用量、海藻酸钠用量、氯化钙用量、枸橼酸钠与氯化钙的质量比为考察变量,采用单因素实验初步确定各变量的范围。以25℃凝胶前体溶液黏度和37℃胶凝黏度为考察指标,采用星点设计-效应面法优选白及多糖pH-离子敏感原位凝胶的处方工艺,并进行预测分析。结果白及多糖pH敏感原位凝胶的最优处方为:去乙酰结冷胶用量为0.50%,海藻酸钠用量为1.10%,氯化钙用量为0.07%,枸橼酸钠与氯化钙的质量比为4∶1。该处方条件下,25℃前体溶液黏度为(704.00±3.00)mPa·s,37℃胶凝黏度为(12544.70±47.33)mPa·s。结论白及多糖pH-离子敏感原位凝胶稳定性好,前体溶液在25℃流动性良好,凝胶强度良好,可为基于白及多糖原位凝胶的后续研究提供实验基础。

层次分析-熵权法联合星点设计-响应面法优选胆汁制陈皮炮制工艺及饮片色度与成分相关性分析

目的研究胆汁制陈皮炮制的最佳工艺参数,明确饮片色度与主要成分之间的关系。方法采用星点设计-响应面法,以辅料用量、蒸制时间、干燥时间、干燥温度为考察因素,以橙皮苷、川陈皮素、橘皮素、牛磺胆酸钠含量及外观性状、醇浸出物含量为评价指标,采用层次分析-熵权法对各评价指标赋予相应权重,计算总评归一值,优选最佳炮制工艺;采用相关性分析和回归分析研究饮片色度与主要有效成分含量的相关性,构建色度-成分的回归方程。结果胆汁制陈皮最佳炮制工艺为每100g陈皮用20g蛇胆汁浸渍完全后,蒸制15min,45℃干燥162min。饮片色度值L^(*)、b^(*)值与橙皮苷、川陈皮素、橘皮素、牛磺胆酸钠4种成分含量均具有显著相关性,a^(*)值仅与牛磺胆酸钠含量具有相关性;构建了L^(*)、b^(*)值与4种成分含量及a^(*)值与牛磺胆酸钠含量的线性回归方程。结论采用星点设计-响应面法优化的胆汁制陈皮炮制工艺具有合理性、可行性,饮片色度与成分含量具有显著相关性。

星点设计-效应面法优化超声提取桂籽中三萜化合物的工艺研究

目的本研究以桂籽为原材料,采用星点设计(CCD)-效应面法(RSM)等多种方法优化桂籽总三萜(OFSTT)的提取工艺及其含量测定研究。方法采用单因素、Plackett-Burman(PB)、最陡爬坡和CCD-RSM实验,建立各因素与响应值之间的数学模型,确定OFSTT的最佳超声提取工艺。结果通过单因素试验,得到了关于桂籽总三萜含量变化的趋势线,进一步利用PB实验筛选出对OFSTT产生显著影响的因素(提取功率、液料比及提取次数),通过最陡爬坡实验设计出极值点,以此作为效应面设计的中心点,采用星点设计-效应面法优化了OFSTT提取工艺的最佳提取工艺条件:乙醇溶剂分数60%,液料比25∶1(mL/g),提取温度65℃,提取功率325W,提取时间30min,提取3次;该条件下OFSTT的提取率为7.251%,实际值与预测值的偏差为2.05%。结论本研究采用CCD-RSM实验优化了OFSTT的提取工艺,该工艺稳定,提取率较高,实际值与预测值吻合度高,为后续桂籽三萜类物质进一步结构鉴定及生物活性作用研究提供参考价值。

水飞蓟素磷脂复合物的制备及体外溶出行为评价

目的将水飞蓟素和磷脂复合以研制水飞蓟素磷脂复合物(silymarin phospholipids complex,SM-PC),并考察其基本理化性质。方法采用溶剂挥发法制备SM-PC。通过前期的单因素考察,选择脂药比、药物浓度以及反应温度作为星点设计-效应面法的考察因素,以SM-PC的复合率为衡量指标筛选最佳研制工艺,并测定SM-PC的体外溶出度。结果SM-PC的最优制备条件如下:以丙酮为反应溶剂,水飞蓟素与大豆卵磷脂的比例为1∶1.8,反应温度56℃,反应物的浓度8.0 mg/ml。在此条件下制备3批样品得到SM-PC的复合率为(95.15±1.55)%,偏差<3%。体外溶出试验表明,SM-PC各组分在60 min的溶出接近90%,主要成分水飞蓟宾的溶出行为与市售水飞蓟素胶囊相似,远高于原料药。结论采用星点设计-效应面法成功制备SM-PC,明显提高了溶出度,为后续制剂的研究奠定基础。

白簕多糖颗粒剂的制备工艺研究

目的 研究白簕多糖颗粒的制备工艺。方法 采用湿法制粒工艺制备颗粒,以成型率、休止角、溶化性作为颗粒剂制备工艺的考察指标。应用单因素法考察多糖与稀释剂配比、润湿剂浓度与用量、干燥温度、干燥时间对颗粒剂质量的影响;在此基础上,以多糖与稀释剂配比、润湿剂浓度、润湿剂用量为考察因素,采用星点设计-响应面法优化处方,并进行工艺验证,计算综合评分评估制备工艺的可行性。结果 最优制备工艺为:赤藓糖醇与白簕多糖配比为3.22:1、润湿剂乙醇浓度为73.68%、乙醇用量为17.51%,在该条件下制备的白簕多糖颗粒剂的成型率达93.60%,休止角为28.20°,溶化率达98.12%,平均综合评分为97.24。制得的白簕多糖颗粒剂在外观、粒度、水分、总糖含量等方面均符合2020年版《中国药典》颗粒剂项下要求。结论 该制备工艺稳定可行,质量可靠。

骨伤跌打康复凝胶贴膏剂处方优选

目的优选骨伤跌打康复凝胶贴膏剂处方。方法以制剂的初黏力、持黏力、综合感官评分的归一化值为评价指标,以聚丙烯酸钠、甘羟铝、聚维酮K90、酒石酸、甘油、中药粉用量为影响因素,采用Plackett-Burman试验和星点设计-响应面法优选制剂处方,并验证。结果该凝胶贴膏剂制备工艺的关键因素为聚丙烯酸钠、甘羟铝、聚维酮K90的用量,最优处方配比为聚丙烯酸钠5.5 g、聚维酮K902.9 g、甘羟铝0.2 g。制得3批制剂的平均归一化值为0.8044,与理论值(0.817)接近(RSD为1.90%)。结论优化处方后的制剂外观均匀,黏性良好,符合凝胶贴膏剂的质量要求。

苦参止痒膏制备工艺研究

目的优选并确立苦参止痒膏的最佳制备工艺。方法采用水煎煮法,选择加水量、浸泡时间、煎煮时间为考察因素,以浸膏得率为评价指标,采用L_(9)(3^(4))正交试验优选提取条件;以油相用量、载药量、乳化剂用量为自变量,设计苦参止痒膏制备工艺的响应面试验,确定最佳制备条件。结果苦参止痒膏最优提取工艺为10倍的水,浸泡处方4 h,煎煮2 h;乳膏最佳制备工艺为油相用量10%(g·g^(-1)),载药量2.5%(g·g^(-1)),乳化剂用量为5.0%(g·g^(-1)),所制得的乳膏质量和性状最好。结论新的制备工艺简便、稳定可行,模型预测功能良好,可为中药新药的开发及工业化放大生产提供参考。

Media optimization for extracellular amylase production by Pseudomonas balearica vitps19 using response surface methodology

BACKGROUND： In this study, we optimized the process for enhancing amylase production from Pseudomonas balearica VITPS 19 isolated from agricultural lands in Kolathur, India. METHODS： Process optimization for enhancing amylase production from the isolate was carried out by Response Surface Methodology （RSM） with optimized chemical and physical sources using Design expert v.7.0. A central composite design was used to evaluate the interaction between parameters. Interaction between four factors - maltose （C-source）, malt extract （N- source）, pH, and CaCl2 was studied. RESULTS： The factors pH and CaCl2 concentration were found to affect amylase production. Validation of the experiment showed a nearly twofold increase in alpha amylase production. CONCLUSION： Amylase production was thus optimized and increased yield was achieved.

Pseudomonas sp.ZXY-1,a newly isolated and highly efficient atrazine-degrading bacterium,and optimization of biodegradation using response surface methodology

Atrazine, a widely used herbicide, is increasing the agricultural production effectively, while also causing great environmental concern. Efficient atrazine-degrading bacterium is necessary to removal atrazine rapidly to keep a safe environment. In the present study, a new atrazine-degrading strain ZXY-1, identified as Pseudomonas, was isolated. This new isolated strain has a strong ability to biodegrade atrazine with a high efficiency of 9.09 mg/L/hr.Temperature, p H, inoculum size and initial atrazine concentration were examined to further optimize the degradation of atrazine, and the synthetic effect of these factors were investigated by the response surface methodology. With a high quadratic polynomial mathematical model（R^2= 0.9821） being obtained, the highest biodegradation efficiency of 19.03 mg/L/hr was reached compared to previous reports under the optimal conditions（30.71°C, pH 7.14, 4.23%（V/V） inoculum size and 157.1 mg/L initial atrazine concentration）.Overall, this study provided an efficient bacterium and approach that could be potentially useful for the bioremediation of wastewater containing atrazine.

Removal of malachite green from aqueous solution by sorption on hydrilla verticillata biomass using response surface methodology

In the present study,the effect of adsorbent dose,pH,temperature,initial dye concentration and contact time on malachite green removal from an aqueous medium using hydrilla verticillata biomass has been investigated.The central composite face-centered experimental design(CFCD)in respons surface methodol-ogy(RSM)was used for designing the experiments as well as for full response surface estimation.The optimum conditions for maximum removal of malachite green from an aqueous solution of 75.52mg/L were as follows:adsorbent dose(11.14g/L),pH(8.4),temperature(48.4℃)and contact time(194.5min).This was evidenced by the higher value of coefficient of determination(R^(2)=0.9158).