响应面法优化微波辅助提取长茎葡萄蕨藻中蕨藻红素

文中采用响应面微波提取法对长茎葡萄蕨藻中蕨藻红素的提取工艺进行研究。单因素和Box-Behnken设计实验结果表明:微波功率、乙醇浓度、料液比、萃取时间、萃取温度对长茎葡萄蕨藻中蕨藻红素提取率有显著影响。优化的提取工艺为微波功率200 W,乙醇体积分数为85%,料液比为1∶30(g∶m L),萃取时间为20 min,萃取温度为45℃,在此条件下长茎葡萄蕨藻中蕨藻红素提取率为91.9%,模型的R2=98.4%。与未经微波处理的传统方法超声法、回流法和水浴法相比,微波处理最高可使长茎葡萄蕨藻中蕨藻红素提取率提高79.8%,超声法、回流法和水浴法蕨藻红素的提取率分别为微波提取的71.8%、85.69%和55.77%,且提取时间长,消耗溶剂大。

响应面法优化固定超声辅助提取玫瑰花黄酮的工艺

以玫瑰花为原料,固定超声法辅助乙醇提取黄酮,并采用响应面法进行工艺优化。主要考查了乙醇体积分数、料液比、提取温度、提取时间对黄酮提取得率的影响,优选较佳提取工艺参数:乙醇体积分数60%,料液比0.5∶13 g/mL,提取温度50℃,提取时间76 min,此条件下黄酮提取得率3.77%。

碱蓬籽油脂的超临界CO_2提取工艺优化

碱蓬籽中油脂含量丰富,尤以不饱和脂肪酸甘油酯-亚油酸酯居多,使用超临界CO2提取碱蓬籽油,确定最佳的提取条件。以亚油酸酯得率为指标,考察了提取温度、提取压力、提取时间、夹带剂流量对实验的影响,在单因素的基础上,采用响应面法对工艺进行优化,得到的最佳提取条件为:提取温度46℃,提取压力23.5MPa,提取时间137min,夹带剂流量0.04m L·min-1,在此条件下亚油酸酯得率为15.29%。优化的提取工艺可行,对工业化生产有一定的指导意义。

超声-微波协同提取山茱萸籽油工艺优化研究

研究以正己烷为溶剂超声-微波协同提取山茱萸籽油的工艺。以出油率为指标,通过单因素实验分别考察了微波功率、超声功率、液料比、提取时间对山茱萸籽油出油率的影响。以提取率为指标,利用Design-expert软件设计正交试验,并用响应曲面优化法(RSM)优化山茱萸籽油的提取工艺,确定的最佳提取工艺参数为:微波功率510W,超声功率350W,液料比17:1 mL/g,提取时间10min。在此最佳条件下,山茱萸籽油的一次提取率相对于索氏提取法为121.15±0.09%(出油率为10.90±0.09%,n=3),与理论计算值122.66%基本一致,说明回归模型能较好地预测山茱萸籽油的提取得率。试验结果表明,超声-微波协同提取山茱萸籽油具有提取率高、速度快、操作简便等优点,另外为山茱萸籽的进一步开发提供了参考依据。

航空γ能谱中人工放射性信息提取方法初探

最小二乘法的航空γ能谱解析可有效分离各辐射源的响应谱,基于此获得的人工核素响应谱可有效应用于地面人工核素定位与定量计算。本文针对以往研究的不足展开讨论,依据实验分析获得航空γ能谱中宇宙射线湮灭辐射强度与宇宙射线道计数成线性规律,并利用蒙特卡罗(Monte Carlo,MC)模拟获得航空γ谱仪对宇宙射线中湮灭辐射的响应谱;实验发现可运用"航空γ谱仪对平衡天然铀系地层的响应谱"替代"航空γ谱仪对大气氡子体的响应谱"。并将上述结论应用于静态点源活度反演实验及人工辐射热点定位,证实该方法能更准确地提取人工放射性信息,为核应急中航空γ能谱的有效应用提供参考。

基于BST-PUF模型的轻量型认证与会话密钥交换协议

为解决现有PUF密钥交换协议存在的纠错机制复杂、辅助数据过大而导致的高开销问题,利用新提出的比特自检PUF电路(BST-PUF)设计了一种轻量型认证与密钥交换协议,在含有PUF的密码设备与服务器之间进行安全认证并建立共享会话密钥。协议能实现双向认证与可靠的密钥交换,抵抗篡改攻击、中间人攻击、DoS攻击、物理探测攻击与建模攻击等各种攻击技术。协议采用BST-PUF电路和鲁棒响应提取器来生成可靠的响应,取代传统PUF和纠错码组合,将可靠性标志F作为辅助数据用来恢复密钥,大幅降低纠错复杂性,减少辅助数据长度并提升PUF利用率。

多焦视网膜电流图中诱发成分的生理含义的解释和分离方法研究

诱发成分是指出现在mfERG一阶响应中较后的位置上的一个波形结构。本研究的第一个目的是要对诱发成分的生理含义作出准确描述,另一个目的是提出一个从一阶响应中完整,准确的分离诱发成分的方法。首先,通过分析诱发成分的各个组成信号的视网膜生理含义,指出诱发成分是一阶响应的一个固有成分,表现了视网膜的光适应机制,在波形和生理含义上与mfERG高阶响应相似但存在明显差别。其次,利用在不同刺激频率条件下得到的一阶响应之间的差异特性,设计实验从一阶响应中分离出诱发成分。实验结果还证实了本研究中关于诱发成分和高阶响应在波形上存在差异的推论。

Optimal Ultrasonic Extraction of Pachyman from Jiuzihe Poria cocos

This study was conducted to extract pachyman to the greatest degree with ultrasonic technology, and to determine the content of pachyman by the phe-nol-sulfuric acid method, so as to choose the optimal technique of ultrasonic extrac-tion of pachyman. Firstly, the ultrasonic power, extraction time and solid-to-liquid ra-tio were investigated by ultrasonic extraction method. Then, on this basis, a respon-sible surface experiment was designed, to select the optimal process conditions ac-cording to the index of pachyman yield. The optimized ultrasonic water extraction conditions were as fol ow： ultrasonic power of 100 W, extraction time of 30 min, and solid-to-liquid ratio at 1：40. The Oxford cup method was used to study the an-timicrobial activity of pachyman. lt was found that pachyman could significantly in-hibit Bacilus subtilis_and Staphylococcus aureus.

Extraction Techniques of Krill Oils Optimized with Response Surface Methodology

The research explored the extraction techniques of organic solvents of Antarctic kril oil and the effects of freezing temperature, extractant proportion, ex-traction time, drying temperature and ratio of material and liquid on extraction ratio of Antarctic kril oil. Based on single-factor experiments, optimal extraction conditions were concluded as per response surface methodology, as fol ows： freezing tempera-ture at -38.5 ℃, the ratio of material and liquid at 1 g：6.7 ml, and drying tempera-ture at 66.8 ℃, where the yield rate of crude oil reached 13.71%.

Optimization of the Extraction Technology of Chlorogenic Acid from Sunflower Meal Using Response Surface Methodology

[ Objective] To optimize the ultrasonic-assisted extraction process of chlorogenic acid from sunflower meal. [ Method] Based on the sin-gle-factor test, the extraction factors of ethanol concentration, extraction temperature and extraction time were optimized using the response surface methodology with the extraction rate of chlorogenic acid as the response value. [ Result] The optimum extraction conditions of chlorogenic acid from sunflower meal were 57% of ethanol concentration, 39 min of extraction time, 53 ~C of extraction temperature, 100 W of ultrasonic power, 1 ： 14 （ g/ ml） of solid-liquid ratio and one time of extraction. Under these conditions, the extraction rate of chlorogenic acid was 2.25%. [ Conclusion] Ultra-sonic assisted extraction method has high extraction rate but short time, the study provides a theoretical basis for the industrialized production of chlorogenic acid in sunflower meal.

Bioassay-Guided Extraction of Crude Fucose-Containing Sulphated Polysaccharides from Sargassum fusiforme with Response Surface Methodology

The response surface methodology(RSM) combined with bioassays was employed to optimize the extraction process of crude fucose-containing sulphated polysaccharides(c FCSP) from Sargassum fusiforme. The central composite design(CCD) was used with four variables, five levels, and four responses. The four variables were p H value of hydrochloric acid solution, extraction temperature(℃), ratio of liquid to raw material(m L g^(-1)), and extraction time(h), respectively. Chemical and bioassay indices were used in combination as the response parameters, which included the yield of c FCSP, fucose content, proliferation rate of spleen cells, and lipopolysaccharide-induced proliferation of splenocytes. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis, and examined using the appropriate statistical methods. The best extraction conditions were as follows: the p H value of hydrochloric acid solution was 3.50; the extraction temperature was 100℃; the ratio of liquid to raw material was 15.00 m L g^(-1) and the extraction time was 2.50 h. The experimental yield was close to the predicted from the model. The extract could promote spleen lymphocyte proliferation, especially the lipopolysaccharide-induced lymphocyte proliferation in vitro, which suggested that its immunomodulatory effect on B lymphocytes. Therefore, c FCSP extracted from S. fusiforme could be utilized as an immunostimulant in functional foods and pharmaceutical industry in future.

Optimization of the Extraction Process of Polysaccharides from Tegillarca granosa by Response Surface Methodology

[ Objective] The aim was to use response surface methodology to determine optimum conditions for extraction of polysaccharides from Tegillarca granosa. [ Method] Response surface methodology with three-factors and throe-levels was carried out for optimizing the extraction process of polysacchafides from Tegillarca granosa. A central composite des（gn including independent variables, such as extraction temperature （A）, extraction time （B）, and ethanol concentration （C） was obtained through Box-Benhnken central combination design. Selected response which evaluates the extraction process was polysacchadde yield. [ Result] The independent variable with the largest effect on response was ethanol concentration （C）. The optimum extraction conditions were found to be extraction temperature 69.6℃, extraction time 6.2 h, and ethanol concen- tration of 78% （V/V）, respectively. Under these conditions, the extraction efficiency of polysaccharide can increase to 1. 635%. [ Coaclusioa] Study on the extraction of polysaccharides from Tegillarca granosa could provide certain theoretical direction for extracting polysaccharides from Tegillarca granosa on a large scale.

Optimization of Enzyme-assisted Extraction Technology for Tartary Buckwheat Shell Procyanidins with Response Surface Methodology

This study was conducted to investigate the effects of cellulase dosage, enzymolysis time, pH and enzymolysis temperature on procyanidin extraction rate by single factor experiment, with tartary buckwheat shell as an experimental material.Main process parameters were optimized to obtain a regression model by response surface methodology. The results of variance analysis indicated that the regression model reflected the relationship between buckwheat shell procyanidin extraction rate with enzyme dosage, enzymolysis time, pH and enzymolysis temperature; and the optimal process parameters were enzyme dosage of 6.5 mg/g, enzymolysis time of 1.5 h, pH at 4.7 and enzymolysis temperature at 46 ℃. Three parallel experiments were conducted under these process parameters. In practice, the highest procyanidin extraction rate was 6.78 g/100 g. The relative error between the predicted value of regression model and the actual value was 1.3%. The regression equation fitted the real situation better.

Optimization of Response Surface of Ultrasonic-assisted Extraction of Rizhao Black Tea

[ Objectivel The aim was to determine the optimal technology for ultrasonic-assisted extraction of black tea was determined. [ Methed] Taking Black Tea as materials, the Box-Behnken response surface design method of tea polyphenols ultrasonic-assisted extraction process optimi- zation was applied. The regression optimization model of the ethanol volume fraction, ultrasonic time, and ultrasonic temperature, ethyl acetate extract stalling time and tea polyphenols was established. [ Result] The influence of four factors on the black tea polyphenol solvents affecting size was as follows： ultrasonic time 〉 ethanol volume fraction 〉 stalling extraction time 〉 ultrasound temperature. The best extraction process was ultrasonic time 80 min, volume fraction of 88.99% ethanol, extraction time 89.97 min, ultrasonic temperature of 80℃. At the optimized technical parameters, the black tea phenolic extraction yield can be as high as 73.50%. [ Conclusion] The study provided theoretical basis for the development of tea leaves and black tea.

Research on the Ultrasonic Extraction Technology of Cottonseed Oil

[ Objective ] To optimize the ultrasonic extraction technology of cottonseed oil by response surface methodology. [ Method ] Based on the single factor experiment, the response surface method with three factors at three levels was adopted according to the principle of central composite design, The optimum extraction conditions of extraction duration, liquid-solid ratio and temperature were determined by regression analysis. [ Re- salt] The best ultrasonic extraction conditions of cottonseed oil were 35 min of extraction duration, 38 ℃ of extraction temperature and 56：6 of liquid-solid ratio. Under these conditions, the extraction rate of cottonseed oil could reach up to 45.81%, with a relative error of 0.13% from the theoreti-cal value of 45.94%. [ Conclusion] The method optimized the extraction technology and laid foundation for the further research of cottonseed oil. Key words Cottonseed oil; Ultrasonic extraction; Response surface method; China

A marked enhancement in production of amylase by Bacillus amyloliquefaciens in flask fermentation using statistical methods

A total of 126 bacterial strains were isolated from soil samples. Among them, 11 isolates were found positive for amylase production. Strain YL produced the largest zone of clearance on plate assay. The isolate YL was identified as Bacillus sp. based on morphological and physiochemical characterization. According to 16S rRNA gene sequencing data, the closest phylogenetic neighbor of strain YL was Bacillus amyloliquefaciens （99.54%）. After that, an optimization of culture conditions was carried out for the improvement of a-amylase production. Response surface methodology （RSM） was applied to evaluate the effect of medium components including wheat bran, cottonseed extract, yeast extract, starch, NaC1 and CaCl2. Three variables （wheat bran, cottonseed extract, and starch）, which were identified to significantly affect amylase production by Plackett-Burman design were further optimized using response surface methodology of Box-Behnken design （BBD）. The optimal concentrations estimated for each variable related to the maximum of amylase activity （86 kU/mL） were 10.80 g/L wheat bran, 9.90 g/L cottonseed extract, 0.5 g/L starch, 2.0 g/L yeast extract, 5.00 g/L NaCl and 2.00 g/L CaC12. The fermentation using optimized culture medium allowed a significant increase in amylase production （by 3-fold）. The improvement in the a-amylase production after optimization process can be considered adequate for large-scale applications.

Optimization of Culture Components for Laccase Activity from Pleurotus Ostreatus P40 Using Response Surface Methodology

High enzymatic activity is required for laccase applications.Central composite design （CCD）-based response surface methodology （RSM） can effectively increase the enzymatic activity of Pleurotus ostreatus P40 in liquid substrate fermentation.Initial screening of the nutritional components was performed using a Plackett-Burman design.The variables,namely,bran,bagasse,Tween 80,and yeast extract,were found to have statistically significant effects on laccase activity.These variables were further optimized using CCD-based RSM.Optimal concentrations for the maximum laccase activity were 8.144 2 g/L bran,50 g/L bagasse,0.424 1 mL/L Tween 80,and 2.832 5 g/L yeast extract.Under optimized conditions,the maximum measured laccase activity reached 96 480 U/L,which was close to the predicted value （104 830 U/L） by RSM.Therefore,RSM can be used to optimize culture components for laccase activity from Pieurotus ostreatus P40.

乌骨鸡中黑色素的研究历程

乌骨鸡是我国特有珍禽，其所含黑色素有许多有价值的作用。本文探索了进几年来人们对于乌骨鸡中黑色素中的各项不同层次的研究。本文从乌骨鸡中黑色素的重要作用开始，概述了蛋白酶法分离黑色素，黑色素抗紫外线功能研究和响应面分析法优化提取工艺。

Optimization of ultrasound assisted extraction of six major compounds from Cimicifugae Rhizome

Cimicifugae Rhizome （RC） is one of many commonly used traditional Chinese medicines. This study used Box-Behnken Design （BBD）, a widely used form of response surface methodology （RSM）, to optimize the conditions of the ultrasound-assisted extraction （UAE） for the extraction of phenolic compounds from CimicifugaeRhizome. The influence of three independent variables, including ethanol concentration （%）, extraction time （min） and solvent-to-material ratio （mL/g）, on the extraction yields of phenolic compounds were examined. The results demonstrated that the optimal ultrasound-assisted extraction （UAE） conditions were as follows： ethanol concentration of 68%, an extraction time of 19 min, and solvent-to-material ratio of 30 mL/g for the extraction of caffeic acid, cimicifugoside, ferulic acid, isoferulicacid, cimifugin, 4′-O-β-glucopyranosyl-5-O-methylvisamminol. These results demonstrated the suitability of UAE for the extraction of phenolic compounds from CimicifugaeRhizome.

Optimization of ultrasound assisted extraction of celastrol from Celastrus monospermus Roxb.using response surface methodology

In the present study, we aimed to investigate the effects of key extraction parameters including extraction time（10–20 min）, extraction temperature（30–60 °C）, ultrasonic power（60–90 W） and solvent-to-solid（S/S） ratio（10–30 m L/g） on yield of celastrol from Celastrus monospermus Roxb. To optimize the conditions, we investigated the effects of parameters on the ultrasound assisted extraction（UAE） with the Box-Behnken Design（BBD）, one widely used form of Response Surface Methodology（RSM）. In all tested solvents, ethanol was the most effective for celastrol extraction, followed by methanol, ethanol, ethyl acetate, n-butanol and water. A second order polynomial model was fitted well to the extraction experimental data with R2 of 0.9928. Extraction yield of 3.116 mg/g was obtained for celastrol under the optimized extraction conditions of extraction time（20 min）, extraction temperature（46 °C）, ultrasonic power（60 W） and S/S ratio（30 m L/g）. Experimental validation was performed, and the experimental values agreed well with the predicted values. The results indicated that the UAE was good extraction material for celastrol from C. monospermus Roxb.