响应面法优化微波辅助水蒸气蒸馏法提取汉麻叶精油工艺

为推动汉麻资源的深度开发利用,提高汉麻叶的附加价值,采用微波辅助水蒸气蒸馏(MAHD)法提取汉麻叶精油。通过单因素实验和响应面法优化汉麻叶精油提取工艺,选取提取时间、料液比、微波辐射时间、微波功率为考察因素,以汉麻叶精油提取率为评价指标进行单因素实验,再进行响应面分析优化。结合提取工艺的实际可操作性和便利性,确定最佳提取工艺为提取时间8.7 h、料液比1∶8(g/mL)、微波辐射时间10 min、微波功率480 W,最终实际提取率为0.210%,与理论值0.213%相接近。MAHD法在汉麻叶精油提取方面,具有实用性和开发性。     

响应面优化微波辅助加热酸法提取果胶工艺

以苹果渣为原料,利用微波辅助加热柠檬酸水解法提取果胶,在单因素实验的基础上,采用Box-Benhnken实验设计方案对提取条件进行优化。结果表明,果胶提取的最佳工艺参数为V(柠檬酸)∶m(果渣)=25.42 mL/g, pH=1.95,水解温度90.41℃,水解时间1.43 h,微波辐射功率907 W,辐射时间7.14 min,果胶提取率的理论响应值为18.05%。     

响应面法优化椪柑果皮精油提取新技术工艺研究

以靖安椪柑鲜果皮为原料,采用超声——微波协同萃取--有机溶剂相结合的集成技术提取果皮精油。考察了提取时间、提取温度及料液比对椪柑鲜果皮精油得率的影响,并采用响应面法建立了精油得率与提取时间、提取温度及料液比之间的关系,得到了最佳提取工艺条件：提取时间12.0min,提取温度为50.5℃、料液比为8.2：1（ml：g）。...     

水蒸气蒸馏提取玫瑰精油工艺的优化

采取水蒸气蒸馏法提取玫瑰精油。在单因素实验基础上,运用正交试验设计对玫瑰精油提取工艺进行优化,考察了花液比、NaCl浓度、加热时间对玫瑰精油提取率的影响。结果表明,加热时间对玫瑰精油提取率的影响最大,其次是NaCl浓度,最后是花液比:NaCl浓度为7.5%,蒸馏时间4小时,花液比1∶4时的得油率最高,为0.140%。     

响应面法优化微波辅助提取女贞子中齐墩果酸的工艺研究

采用微波提取方法提取女贞子果中的活性成分齐墩果酸。在单因素实验的基础上通过响应面法优化了提取工艺:体积分数为91%的乙醇溶液,微波温度62℃,微波时间3 min,微波功率300W,料液比为1∶11(g/m L),此条件下齐墩果酸的预测最大提取率为2.119%,实际最大提取率为2.105%。     

响应面法优化红豆越橘花色苷的微波辅助提取工艺

以花青素含量为评价指标,通过单因素实验和响应面法优化了红豆越橘花色苷的微波辅助提取工艺。确定最佳提取工艺为：乙醇体积分数80%、微波时间125 s、微波温度52℃、料液比1∶26(g∶mL),在此条件下,红豆越橘中花青素含量为19.88%。     

分子蒸馏纯化姜精油工艺的响应面法优化研究

借助分子蒸馏技术来对超临界CO_2进行相应的萃取就可以获取姜油树脂,然后借助相关手段对其进行纯化处理后就得到了姜精油。以单因素实验过程中所涉及到的分子蒸馏的压力和温度作为中心复合设计变量,以α–姜烯含量和姜精油收率作为指标来实现对响应面法的优化。结果表明:分子蒸馏的压力、温度对姜精油中α–姜烯含量及纯化姜精油的收率有一定的影响。     

响应面法优化微波辅助提取板栗壳色素

以板栗壳为原料,利用微波辅助提取板栗壳中的棕色素。在单因素实验的基础上,运用响应面分析法进一步对板栗壳色素的微波提取条件进行优化,并研究了各因素间的交互作用。研究结果表明,在重复提取3次的条件下,当1.0wt%Na HCO3为提取溶剂、料-液比为1∶25(g/m L)、辐照时间为6 min、微波功率为462 W,再将粗提液经酸沉、重结晶后,板栗壳色素的提取率达到了15.5%。响应面分析结果显示,功率对提取效率的影响最为显著,表明微波法可较好地应用于板栗壳棕色素的提取。     

响应面法优化百合多糖的超声辅助提取工艺

在单因素实验的基础上,以液料比、提取时间、超声功率、提取次数为考察因素,以百合多糖得率为评价指标,采用响应面法优化百合多糖的超声辅助提取工艺。确定最佳提取工艺为:液料比21∶1 (mL∶g)、提取时间4 min、超声功率400 W、提取次数2次,在此条件下,百合多糖得率为12.936%,与预测值(13.150%)相差0.214%。该优化提取工艺合理、可行,可用于百合多糖的提取。     

响应面法优化侧柏叶总黄酮提取工艺

利用超声波辅助提取侧柏叶总黄酮,用分光光度法分析其含量。研究了乙醇浓度、超声提取时间、液料比对侧柏叶总黄酮提取的影响。在单因素实验的基础上,以侧柏叶总黄酮提取率为响应值,以乙醇浓度、超声提取时间、液料比为自变量,通过三因素三水平Box-Bohnken响应面分析法对筛选出的提取工艺进行优化。结果表明,响应面法优化得到的最佳提取工艺为:在乙醇浓度73%、提取时间42 min、液料比为80∶1 mL/g,此实验条件下重复3次验证实验得到的侧柏叶总黄酮平均提取率为2.45%,与Box-Bohnken响应面分析法模拟预测值2.47%相差较小,所建模型与采用的优化方法可靠。     

响应面分析法优化生姜挥发油提取工艺

在单因素实验的基础上,采用中心组合实验设计及响应面分析法优化了生姜中挥发油的水蒸汽蒸馏提取工艺。结果表明,提取时间(p<0.01),料液比(p<0.05)对挥发油提取得率具有显著影响。最佳工艺条件为:生姜干燥后粉碎过60目筛,加水15.6倍,水蒸汽蒸馏4.78 h。在此条件下,挥发油得率为2.00%,实验结果与模型预测值相符。     

响应面法优化微波辅助合成中碳链甘油三酯工艺

以对甲苯磺酸为催化剂,在微波环境下合成辛酸癸酸甘油三酯,并利用响应面法优化辛酸癸酸甘油三酯的合成过程条件。首先,通过单因素灵敏度分析法对催化剂的选择、酸/醇摩尔比、反应温度、微波功率、催化剂用量、反应时间6个因素进行实验考察,确定了酸/醇摩尔比、反应温度、催化剂用量3个关键因素的优化值及取值范围。采用中心组合设计原则对3个关键因素进行实验设计。以产品羟值为响应值,基于响应实验结果,利用响应面法对实验结果进行了方程回归,得到3个关键因素与响应值的二次关联模型。通过方差分析和平行实验,证明该模型准确可用。确定了中碳链甘油三酯（MCTs）最佳合成条件为：酸/醇摩尔比为3.33：1,反应温度为190℃,催化剂用量为甘油质量的4.30%,微波功率为500 W,反应时间为3 h,得到产品羟值为1.12 mg KOH·g^-1,酯化率高达99.7%,与理论预测值基本相符。与传统加热方式对比,微波辅助合成MCT大大缩短了反应时间。测定了精制提纯后MCT产品的各项物化性能指标,均已达到企业标准。通过红外光谱表征和GC/MS进一步表征产物结构和混合物油脂的组成,甘油三酯得率达到95.7%。     

Optimization of oil and carotenes recoveries from palm oil mill effluent using response surface methodology

BACKGROUND: Palm oil mill effluent (POME) is a liquid waste that is highly polluting and has a significant impact on the environment if not dealt with properly. POME contains oil and carotenes that needs to be treated before discharge. In this work solvent extraction was used to recover oil‐containing carotenes from POME. Optimum conditions for the extraction of oil and carotenes from POME were determined using response surface methodology. RESULTS: A central composite design was used to investigate the effects of three independent factors, namely solvent:POME ratio, mixing rate (rpm) and mixing time (min) on the responses, extracted oil and carotenes recovery. The optimal conditions for extraction of oil and carotenes from POME were 8:10 solvent:POME ratio; 500 rpm mixing rate and 25 min mixing time. Under these conditions, the amount of oil extracted from POME was 7885 mg L^?1, and carotenes recovery was 87.1%. CONCLUSION: The experimental values agreed with those predicted, thus indicating the suitability of the model employed in optimizing the extraction parameters. A high yield of carotenes was obtained under the optimized conditions, with relatively low solvent levels. Copyright © 2009 Society of Chemical Industry     

Supercritical extraction of evening primrose oil: Experimental optimization via response surface methodology

Supercritical carbon dioxide (CO₂) effective extraction parameters (pressure, temperature, static extraction time, and dynamic extraction time) of oil recovery from evening primrose seeds were optimized via response surface methodology (RSM). The results of this study indicated that the linear terms of static and dynamic time and the quadratics of temperature and pressure, as well as the interactions of temperature and static time, pressure and temperature had a significant effect on the oil recovery. The optimum extraction conditions of 14.2 MPa, 47.3°C, 30 min (static extraction time) and 150 min (dynamic extraction time) were obtained. Applying the optimum conditions, a mean experimental recovery of 92.98% (triplicate experiment) was achieved, which is well compatible with the RSM‐predicted value (93.61%). The fatty acid composition of extracted evening primrose oil using supercritical CO₂ was compared with that obtained by Soxhlet method in which minor difference was observed. © 2011 American Institute of Chemical Engineers AIChE J, 2011     

Optimization of enzymatic methanolysis of soybean oil by response surface methodology

Enzymatic methanolysis of refined soybean oil with methanol was investigated using Rhizomucor miehei lipase, Lipozyme RM IM, in n-hexane for reaction times of 30 min. Response surface methodology (RSM) based on three-level, three-factor (variable) face-centered cube design was used for the optimization of methanolysis. The independent variables that affect the methanolysis reaction conducted in n-hexane are temperature (°C), enzyme/oil weight ratio, and oil/methanol molar ratio. A good quadratic model was obtained for the methyl ester production by multiple regression and backward elimination. A linear relationship was observed between the observed and predicted values (R²−0.9635). The effects of temperature and enzyme amount, which affected methyl ester content of the product (response) positively, were significant (P<0.01). The quadratic term of temperature and the interaction term of enzyme amount with temperature affected the response negatively (P<0.01). The interaction term of enzyme amount with substrate mole ratio had a positive effect on the response (P<0.05). Critical conditions for the response at which methyl ester content of the product was 76.9% were determined to be 50°C, 2.37 methanol/oil mole ratio, and 0.09 enzyme/oil weight ratio.     

响应曲面法优化超临界CO2萃取猕猴桃籽油条件

以猕猴桃籽为试验原料,在单因素试验的基础上,采用响应曲面分析法建立了超临界CO2萃取猕猴桃籽油萃取率的二次多元回归方程,探讨了压力、温度、CO2流量等关键因素对萃取率的作用规律。结果表明,萃取压力、温度、CO2流量对萃取率影响显著,萃取压力和温度交互效应影响显著。根据萃取率回归方程对猕猴桃籽油的超临界萃取工艺参数进行了优选,最优工艺参数为:压力31.7 MPa,温度40.2℃,CO2流量27.4 kg/h,该条件下萃取率高达32.57%,与试验值31.24%仅有4.5%的误差,证实了该方程的预测值与试验值之间具有较好的拟合度。超临界CO2萃取的猕猴桃籽油与己烷提取的油脂在脂肪酸组成上没有显著差别。     

The kinetic modelling of a steam distillation unit for the extraction of aniseed (Pimpinella anisum) essential oil

A simplified model that considered the oil constituents as one constituent, anethole, the major component, was used to describe the mass transfer of steam extraction of aniseed essential oil. The model can be used to optimise and control the process. Depending on the oil content, two mass transfer regimes were identified (i) the first one corresponds to an unsaturated surface extraction and (ii) the second corresponds to the slower transfer of oil from the deeper parts of the material to the surface, which may be due to concentration gradients and chemical bonding. The model was validated by experimental data obtained from a pilot‐plant system. Solid‐steam mass transfer coefficients were determined and a critical oil content was found to limit the two mass transfer regimes. The value for this critical oil concentration (x_B) was found to be 0.011 (g oil g^?1 solid). In addition, an optimal operating pressure of 200 kPa was found to give maximum extraction yield. Copyright © 2005 Society of Chemical Industry     

响应曲面法优化蜂胶中的活性黄酮提取

探讨了超声波辅助技术提取蜂胶中的活性黄酮类化合物的工艺。实验以芦丁为标样,在单因素实验基础上,采用Box-Behnken实验设计方法,以提取温度、固液比、提取时间以及乙醇浓度为自变量,黄酮提取率为响应值,研究各自变量及其交互作用对黄酮提取率的影响。利用Design expert软件,建立了提取率与超声波处理各因素的二次多项式数学模型,获得了蜂胶中黄酮的最佳提取条件为:提取温度51.32℃,固液比1∶10,提取时间12.88 min,乙醇浓度88.86%,最佳黄酮提取率为52.39%。经过实验验证,黄酮提取率可达51.98%。     

Optimization of supercritical CO2 extraction of dried Helichrysum italicum flowers by response surface methodology: GC-MS profiles of the extracts and essential oil

Supercritical (SC) CO₂ extraction of dried Immortelle flowers was performed at different process parameters. The optimal extraction conditions related to the yield were determined by response surface methodology (yield 4.09% at 20 MPa and 52°C). The extracts were analyzed by GC-MS and tremetone derivatives dominated: bitalin A, 12-acetoxytremetone, gnaphaliol, 1-[2-(2-methyl-2,3-dihydroxypropyl)-2,3-dihydro-1-benzofuran-5-yl]ethanone, isobutyl bitalin A, and 1-[2-(acetylprop-1-en-2-yl)-3-hydroxy-2,3-dihydro-1-benzofuran-5-yl]ethanone. Striking differences were found among the essential oil and SC-CO₂ extracts composition. The major oil compounds were γ-curcumene, α-pinene, β-selinene, α-selinene, and limonene. Mono- and sesquiterpene were found among minor constituents of the extracts. Neryl acetate was present in the extracts and essential oil.     

Optimization of essential oil supercritical extraction from Algerian Myrtus communis L. leaves using response surface methodology

The present work deals with the application of the supercritical fluid extraction process to extract essential oils from the leaves of an Algerian myrtle plant (Myrtus communis L.). Using the surface response methodology, an optimization of the extraction recovery was carried out, varying the pressure in the range of [10–30 MPa], the temperature within [308–323 K], a solvent flow rate fixed at 0.42 kg h⁻¹ and a mean particle diameter equal to 0.5 mm or less than 0.315 mm. The maximum value of essential oil recovery relative to the initial mass of leaf powder was 4.89 wt%, and was obtained when the SC–CO₂ extraction was carried out under 313 K, 30 MPa and with a particle diameter less than 0.315 mm. A second-order polynomial expression was used to express the oil recovery. The calculated mass of recovered oil using the response surface methodology was very close to the experimental value, confirming the reliability of this technique.