响应曲面优化喜树生物碱醇提工艺研究

对喜树果中喜树碱的最佳醇提工艺条件进行了研究。采用乙醇浸提法,考查了乙醇浓度、液料比、提取温度及提取时间对喜树碱提取率的影响,经过一系列的单因素实验,结合响应曲面实验设计法及响应曲面分析(RSM),得到喜树碱的最佳提取工艺为:乙醇浓度88.53%,液料比21.4∶1(m L/g),时间2.23 h,提取温度40℃,经验证,在此提取工艺条件下,喜树碱提取率可达0.847 mg/g。     

正交设计优选橙皮苷提取工艺研究

采用碱-醇提酸沉法提取陈皮中橙皮苷,首先针对提取温度、提取时间、pH值、碱液料液比、醇液料液比、提取次数等因素对提取率的影响进行单因素实验考察,并进一步利用正交实验对橙皮苷的提取工艺进行优化。得到最优浸提条件为:陈皮粉与食用乙醇料液比为1:10、与0.5%NaOH溶液料液比1:10,浸提温度70℃,浸提时间4 h,提取率最高。     

黑米蛋白提取工艺的优化

以黑米为原料,研究黑米蛋白提取工艺的优化。采用"碱提酸沉"法,研究了提取液pH值、温度、搅拌速度、料液比、提取时间、及粒径大小等对黑米蛋白提取率的影响。在单因素试验的基础上,以L9(34)正交实验法优化黑米蛋白提取工艺。结果表明:各因素对黑米蛋白提取率的影响顺序依次为:pH值粒径料液比转速。本实验中,黑米蛋白提取的最佳工艺条件为:提取液p H 12.5、温度28℃、搅拌转速800 rpm、料液比1∶10 g/m L、提取时间为1 h、酸沉淀时间为1 h、粒径大小为能通过100目筛。优化后黑米水溶性蛋白提取率提高到96.77%,纯度为97.75%。     

响应面法优化青稞秸秆中β-葡聚糖的提取工艺

通过单因素实验结果选取对β-葡聚糖提取率影响较大的A(料液比)、B(提取温度)、C(提取时间)为自变量,以β-葡聚糖与刚果红显色后在550nm处的吸光度(Y)为响应值,进行中心组合实验设计,采用响应面法(RSM)分析这些因素对β-葡聚糖提取率的影响。结果表明:从青稞秸秆中提取β-葡聚糖的最佳工艺条件为料液比44.20m L/g,提取温度80℃,提取时间3.2h,在此条件下提取到β-葡聚糖在550nm处的吸光度为0.2068。     

响应面法优化桑葚多糖的超声波辅助提取工艺条件

本研究利用响应面法优化桑葚多糖的超声波辅助提取工艺条件;选定提取温度、时间及水料比作为影响因素,以桑葚多糖提取率为评价指标,在单因素实验的基础上,通过3因素3水平Box-Behnken中心组合试验建立多糖提取率的二次多项式回归方程,研究超声提取时间、温度、水料比对桑葚多糖提取率的影响;结果显示最佳提取工艺条件为提取温度72℃、超声时间23.5 min、水料比27∶1(v∶m,mL/g),在该条件下多糖提取率预测值为17.80%,验证值为17.78±0.85%(n=3);此方法与传统水提取法相比具有省时、高效的优点,为桑葚多糖的后续研发提供实验基础。     

响应曲面法优化香蕉假茎中的果胶提取工艺

以香蕉假茎为原料,通过单因素实验及响应曲面法对影响果胶提取率的4个主要因素,包括:提取液pH、料液比、提取温度、提取时间进行优化。实验结果显示:香蕉假茎中果胶的最佳提取工艺参数为:pH1.9、料液比(g:mL)1∶40、提取温度79℃、提取时间131 min,该条件下果胶的得率为22.35%,半乳糖醛酸含量符合国家标准。     

响应面法超声辅助提取优化蛇床子素工艺的研究

对独活中蛇床子素超声提取工艺进行了研究。在单因素实验的基础上,选取了对蛇床子素提取率影响较大的4个因素(温度、乙醇体积分数、提取时间和料液比)。采用响应曲面分析法,建立了独活中蛇床子素提取的二次多项式数学模型,优化蛇床子素的超声提取最佳工艺条件,在温度64.63℃,乙醇体积分数73.18%,提取时间45.33 min,料液比20.67 mL/g条件下蛇床子素最大提取率达到0.987%。表明响应面法超声辅助提取优化蛇床子素工艺的研究方法简便、可靠。     

响应面法优化红景天总黄酮提取工艺的研究

研究了红景天中总黄酮提取率的影响因素,先经单因素实验初步确定影响因素,再用Box-Behnken响应面法建立影响因素的二次回归模型,通过对二次回归模型求解编码转换得知,液料比40:1(ml/g),酶添加量1.2%,酶解时间4.5 h,酶解温度45℃,pH5,超声时间为12 min,超声功率为250w中的高档,超声次数为3次,在这最优条件下总黄酮提取率为3.99%。     

响应面法优化细果角茴香中总黄酮的超声提取条件

采用响应面法优化超声波辅助提取细果角茴香中总黄酮的工艺研究。在单因素试验的基础上,选择超声时间、乙醇浓度、料液比为自变量,以总黄酮的提取率为响应值,进行Box-Behnken中心组合实验设计,采用响应面法(RSM)评估了这些因素对总黄酮提取率的影响。结果表明:超声波法辅助提取细果角茴香中总黄酮的最佳工艺条件为液料比33 mL/g,乙醇浓度为58%,提取时间为34.5 min。在此条件下,总黄酮的提取率达1.525%。     

枇杷叶中黄酮类化合物提取工艺研究

以枇杷叶为原料,对黄酮类化合物的提取工艺进行研究,考察乙醇浓度、提取温度、提取时间、料液比对枇杷叶中黄酮类化合物提取率的影响,并采用正交实验进行优化。结果表明四种因素对枇杷叶中黄酮类化合物提取率影响的大小顺序为:乙醇浓度>提取时间>提取温度>料液比,枇杷叶中黄酮类化合物提取的最佳工艺条件为提取时间30min、提取温度80℃、乙醇浓度40%、料液比1:20(g/mL),最佳条件下黄酮类化合物提取率为6.92%。     

响应面法优化南方山荷叶中鬼臼毒素的提取工艺

鬼臼毒素（Podophyllotoxin）是一种常用的临床天然药物。本研究以鬼臼类药材南方山荷叶（Diphylleia sinensis H.L.Li）为材料,以提取物中鬼臼毒素的含量为控制指标,应用响应面法优化南方山荷叶中鬼臼毒素的提取工艺。采用高效液相色谱法测定提取物中鬼臼毒素的含量,在单因素实验筛选的基础上,选择出对鬼臼毒素提取率影响较大的3个因素：乙醇浓度、提取温度和提取时间,然后利用Design-expert软件设计3因素3水平响应面实验,最终获得鬼臼毒素提取率最高时的提取条件为：乙醇浓度48.18%、提取温度62.66℃、提取时间16.15 h,此时鬼臼毒素的理论提取率可达7.636%。进一步对该条件进行实验验证,3次实验平均值为7.54%,与理论值差异较小,表明该模型拟合良好,实验方法可靠。     

水提取法分离大豆异黄酮苷和苷元

本文建立了一种仅用水作为溶剂分离大豆异黄酮苷和苷元的方法。采用水加热提取的方法分离大豆异黄酮苷和苷元,分别对所用溶剂,提取温度,提取时间和物料比进行优化。实验上清液干燥后的固形物中大豆异黄酮苷含量为32．24％,苷元含量仅为3．05％,沉淀中大豆异黄酮苷元含量为72．03％,苷含量仅为4．28％。该方法经济,简单,绿色无毒,适合工业生产。     

响应面优化纤维素酶辅助提取木豆叶总黄酮工艺

为探讨纤维素酶辅助提取木豆叶总黄酮最佳工艺条件,在单因素试验基础上,以酶用量、酶解温度、酶解时间和酶解pH为影响因子,总黄酮得率为响应值,采用Box-behnken中心组合设计建立4个影响因子与总黄酮得率关系的数学模型,进行响应面法分析。结果表明,纤维素酶辅助提取木豆叶总黄酮的最佳工艺条件为：酶用量为8.65 mg,酶解温度为33.88℃,酶解时间为2.02 h,酶解pH为5.02。在最优条件下总黄酮理论得率为4.86%,实测值为4.88%,拟合得到的模型与实际吻合良好。本研究建立的提取工艺条件稳定可靠,为以后木豆叶总黄酮的应用开发提供实验依据。     

响应曲面优化醇法提取桑叶黄酮工艺研究

以含水乙醇为溶剂,在单因素试验基础上,采用响应曲面法优化提取桑叶黄酮工艺条件。结果表明,醇法提取桑叶黄酮的最优工艺条件为:乙醇体积分数71.75%、提取温度67.1℃、料液比23.2:1(醇溶液:桑叶粉,mL:g)、提取时间150 min、提取次数2,桑叶黄酮得率为2.37%。验证试验表明,该优化工艺稳定,与模型预测值相符。     

Thermo-mechanical extrusion pretreatment for conversion of soybean hulls to fermentable sugars

Thermo-mechanical extrusion pretreatment for lignocellulosic biomass was investigated using soybean hulls as the substrate. The enzyme cocktail used to hydrolyze pretreated soybean hulls to fermentable sugars was optimized using response surface methodology (RSM). Structural changes in substrate and sugar yields from thermo-mechanical processing were compared with two traditional pretreatment methods that utilized dilute acid (1% sulfuric acid) and alkali (1% sodium hydroxide). Extrusion processing parameters (barrel temperature, in-barrel moisture, screw speed) and processing aids (starch, ethylene glycol) were studied with respect to reducing sugar and glucose yields. The conditions resulting in the highest cellulose to glucose conversion (95%) were screw speed 350 rpm, maximum barrel temperature 80 °C and in-barrel moisture content 40% wb. Compared with untreated soybean hulls, glucose yield from enzymatic hydrolysis of soybean hulls increased by 69.6%, 128.7% and 132.2%, respectively, when pretreated with dilute acid, alkali and extrusion.     

正交试验法优化桑叶多糖提取工艺

以脱除黄酮的桑叶为原料,采用热水浸提法提取桑叶多糖,研究了提取温度、提取时间、料液比、水溶液pH和提取次数对桑叶多糖得率的影响,通过正交实验优化了提取工艺条件。结果表明,在提取次数为2次条件下,桑叶多糖最佳提取工艺条件为提取温度100℃、提取时间4 h、提取液pH7、料液比(原料:提取液,g/mL)1:30,多糖得率为2.74%。该工艺稳定,桑叶多糖得率高,易于工业化生产。     

Optimization of enzymatic hydrolysis of visceral waste proteins of Catla (Catla catla) for preparing protein hydrolysate using a commercial protease

Protein hydrolysate was prepared from visceral waste proteins of Catla (Catla catla), an Indian freshwater major carp. Hydrolysis conditions (viz., time, temperature, pH and enzyme to substrate level) for preparing protein hydrolysates from the fish visceral waste proteins were optimized by response surface methodology (RSM) using a factorial design. Model equation was proposed with regard to the effect of time, temperature, pH and enzyme to substrate level. An enzyme to substrate level of 1.5% (v/w), pH 8.5, temperature of 50 degrees C and a hydrolysis time of 135 min were found to be the optimum conditions to obtain a higher degree of hydrolysis close to 50% using alcalase. The amino acid composition of the protein hydrolysate prepared using the optimized conditions revealed that the protein hydrolysate was similar to FAO/WHO reference protein. The chemical scores computed indicated methionine to be the most limiting amino acid. The protein hydrolysate can well be used to meet the amino acid requirements of juvenile common carp and hence has the potential for application as an ingredient in balanced fish diets.     

An approach for prediction of optimum reaction conditions for laccase-catalyzed bio-transformation of 1-naphthol by response surface methodology (RSM)

Response surface methodology (RSM) was successfully applied to enzymatic bio-transformation of 1-naphthol. The experiments were conducted in a closed system containing acetone and sodium acetate buffer, with laccase enzyme. Laccase enzyme used as catalyst was derived from Trametes versicolor (ATCC 200801). The enzymatic bio-transformation rate of 1-naphthol, based on measurements of initial dissolved oxygen (DO) consumption rate in the closed system, was optimized by the application of RSM. The independent variables, which had been found as the most effective variables on the initial DO consumption rate by screening experiments, were determined as medium temperature, pH and acetone content. A quadratic model was developed through RSM in terms of related independent variables to describe the DO consumption rate as the response. Based on contour plots and variance analysis, optimum operational conditions for maximizing initial DO consumption rate, while keeping acetone content at its minimum value, were 301 K of temperature, pH 6 and acetone content of 7% to obtain 9.17 x 10(-3) mM DO/min for initial oxidation rate.     

Enzyme assisted extraction of polysaccharides from the fruit of Cornus officinalis

Process of enzyme assisted extraction (EAE) of polysaccharides from Cornus officinalis was optimized by response surface methodology (RSM). The influence of four different factors on the yield of C. officinalis polysaccharides (COP) was studied. Results showed that the optimal conditions were compound enzyme amount of 2.15%, extraction pH of 4.2, extraction temperature of 55 °C and extraction time of 97 min. Under these conditions, the COP yield was 9.29 ± 0.31%, which was well in agreement with the value predicted by the model. The three methods, EAE, hot water extraction (HWE), ultrasound-assisted extraction (UAE) for extracting COP by RSM were further compared. Results showed that EAE had the largest yield of polysaccharides with lower equipment cost.     

响应面法优化水酶法提取辣木籽蛋白质的工艺及其功能性质研究

为了提取和利用辣木籽蛋白质,本文通过水酶法优化其提取条件,并探讨其功能性质。以辣木籽为原材料,以蛋白质提取率为指标,首先确定了最佳使用酶为Alcalase碱性蛋白酶,再通过单因素试验考察料液比、时间、温度、酶添加量和pH等因素对蛋白质提取率的影响,在此基础上,利用响应面试验设计优化水酶法提取辣木籽蛋白质的工艺。结果表明,最佳工艺条件为:使用Alcalase碱性蛋白酶,在料液比为1∶10,酶添加量为4.5%,pH为9.0,温度为60℃,时间为4.5 h,此时辣木籽蛋白质的提取率最高为68.23%。在pH为10、温度为55℃时辣木籽蛋白质的氮溶解指数最高;辣木籽蛋白质持水性随着pH的增加而增加,在温度为40℃时持水性最好;在温度为55℃时,辣木籽分离蛋白的吸油效果最明显。