酶法辅助提取紫薯中花青素的研究

通过单因素和正交实验优化酶法提取紫薯花青素的工艺条件。结果表明,以p H 7.0的去离子水为提取液,纤维素酶添加量为0.32 mg/g,液料比40∶1 m L/g,常温下迅速提取1次,花青素得率为5.05 mg/g。     

超声辅助提取紫薯花青素工艺研究

为了优化超声波提取紫薯中花青素工艺,采用单因素和正交实验。结果表明:超声提取紫薯中花青素最佳提取工艺为:盐酸质量分数0.2%,提取温度60℃,提取时间80 min,料液比1︰15(g/mL)。在该条件下得到紫薯中花青素含量为1.954 mg/mL。     

不同品种松树皮活性成分及其提取影响因素

本研究选择华南地区五种松树品种,通过活性成分含量和抗氧化活性复合响应值筛选最佳的松树品种,并分析不同提取条件(提取时间、提取温度、溶剂浓度、液料比和提取次数)对原花青素提取率和清除自由基活性的影响。试验结果表明:不同品种松树树皮活性物质的含量差异显著,马尾松树皮的总多酚含量、总黄酮含量、原花青素和水溶性多糖含量最高,分别为(107.5±6.31)mg/g、(81.1±4.67)mg/g、(36.8±2.31)mg/g和(24.9±3.17)mg/g。通过马尾松树皮原花青素含量和清除DPPH自由基能力复合响应值分析,不同的提取条件对其影响显著,最佳影响因素为乙醇浓度为60%,提取温度50℃,提取时间90 min,液料比25∶1。     

酶法提取洛神花中花青素的工艺优化

对酶法提取洛神花中花青素的工艺进行了优化。结果显示,在煎煮时间为60 s,提取温度为55℃,水解作用时间60 min条件下,果胶酶Ultra Mash和果胶酶Yield Mash(120 mL/t∶45 mL/t)的组合酶可获得最高浓度的花青素711.5 mg/100 g;该提取法的花青素得率跟无酶对照样品相比提高了119.8%。此外,通过微波辅助条件的优化(微波时间40 s,微波功率600 W)进一步提高了花青素的提取浓度至774.1 mg/100 g,花青素得率跟无酶对照样品相比提高了139.2%。     

响应曲面法优化超声辅助提取油菜籽皮中的原花青素

以乙醇为提取剂,用超声辅助的方法从油菜籽皮中提取了原花青素。在讨论了提取剂体积分数、提取时间、液料比(每克原料加入提取剂的毫升数,简称液料比,以下同)和超声波功率等单因素实验的基础上,运用Box-Behnken中心组合实验和响应曲面法分析了提取剂体积分数、提取时间和液料比3个因素对原花青素提取率的影响,并优化了提取工艺。结果表明,最佳的工艺条件为:乙醇体积分数62.9%,提取时间20.8 min,液料比25 mL/g。在该条件下,原花青素提取率的预测值为5.055 mg/g,验证实验值为5.02 mg/g,说明响应曲面法优化油菜籽皮中原花青素提取工艺是可行的。     

酶法提取洛神花中花青素的工艺优化

对酶法提取洛神花中花青素的工艺进行了优化。结果显示,在煎煮时间为60 s,提取温度为55℃,水解作用时间60 min条件下,果胶酶Ultra Mash和果胶酶Yield Mash(120 mL/t∶45 mL/t)的组合酶可获得最高浓度的花青素711.5 mg/100 g;该提取法的花青素得率跟无酶对照样品相比提高了119.8%。此外,通过微波辅助条件的优化(微波时间40 s,微波功率600 W)进一步提高了花青素的提取浓度至774.1 mg/100 g,花青素得率跟无酶对照样品相比提高了139.2%。     

柳树叶中原花青素的提取与含量测定

以乙醇提取柳树叶的原花青素,考察了乙醇浓度、料液比、提取时间和提取温度等对提取率的影响。结果表明,乙醇浓度70%,料液比1∶20,提取温度70℃,提取时间120 min为最佳提取条件。运用香草醛-盐酸显色法,对最佳提取条件下提取的柳树叶中原花青素含量进行测定,测得绥化地产柳树叶中原花青素含量为10.77 mg/g。     

微波辅助低共熔溶剂高效提取油茶壳原花青素的工艺优化

氯化胆碱/草酸体系的低共熔溶剂作为提取溶剂,采用微波辐照萃取,分离油茶壳原花青素,研究微波功率、原料粒径、微波温度、微波时间、溶剂含水量和料液比对油茶壳原花青素提取量的影响。结果表明,油茶壳原花青素的最佳提取工艺参数。原料过200目筛而不过400目筛(平均粒径为53μm),溶剂含水量5%,料液比1∶20 (g/mL), 600 W的微波功率,35℃微波辐照提取60 min。在此优化条件下,油茶壳中原花青素的提取量为66.89 mg/g。     

微波辅助复合酶提取黑米花青素的工艺及数学模型分析

采用微波辅助-复合酶法提取黑米中的花青素。通过响应面法考察了复合酶(纤维素酶与果胶酶质量比为1∶1)用量、液料比、微波时间和微波功率对花青素得率的影响。结果表明：最佳提取条件为复合酶用量4.8 mg/g、液料比48∶1(m L∶g)、微波时间9 min、微波功率330 W，在此条件下进行黑米花青素的提取，可得花青素得率的平均值为(0.6689±0.0125)%。建立了5种数学模型对不同液料比下的黑米花青素的提取规律进行拟合，通过模型评价参数及验证试验，证实Cubic模型是描述黑米花青素提取过程的最佳数学模型。     

微波辅助提取龙葵浆果中花青素工艺研究

以野生龙葵浆果为原料,优化其花青素的最佳微波提取工艺:盐酸水溶液与物料的最佳液固比为17.5∶1,盐酸浓度为0.75%,微波辐射功率为700 W,提取温度为70℃,提取时间为6 min;并用pH值示差法测定龙葵浆果中花青素含量为1.806±0.016 mg/g。     

Mechanical extraction

The mechanical screw press was the principal means of extracting vegetable oilseeds in the United States from the 1930s through the 1940s and 1950s. Then the utilization of solvent extraction cut drastically into their use for full extraction, but created a great demand for screw presses for prepressing of high oil content seeds for solvent extraction. However, use of the screw press for full extraction has been increasing over the years in the less developed countries, and is the main modern machine utilized for some products such as palm fruit. Today ever larger and more efficient machines are being developed for full extraction and pre-pressing of vegetable oilseeds and fruits.     

Using membrane-supported liquid-liquid extraction for the measurement of extraction kinetics

Membrane-supported liquid-liquid extraction uses artificial membranes for the generation of a phase interface between the two liquid phases involved in extraction. Additional equipment for the generation of droplets as well as phase separation afterwards is no longer necessary. Since the membranes used for this special type of extraction are quite well described concerning thickness, porosity, tortuosity and material it is possible to generate information about the diffusion coefficient of the component to be extracted within the preferred solvent from extraction trails easily. This article describes an experimental set-up for both the proof of principle of membrane-supported liquid-liquid extraction and, using a dedicated computer-aided data treatment, how to calculate the overall mass transfer coefficient as well as the diffusion coefficient for a given system within moderate testing duration.     

加压溶剂法提取雷公藤甲素及其条件优化

以雷公藤为原料,采用加压溶剂法提取雷公藤甲素,以1,2-二氯乙烷为溶剂,考察了提取时间、料液比和提取温度等因素对提取工艺的影响,并在单因素试验基础上,根据中心组合试验设计原理采用三因素三水平的响应面分析法进行工艺优化,得到提取过程优化的工艺条件为:料液比1:9.7,提取温度115℃,提取时间80min,雷公藤甲素的实际得率可达0.173‰,纯度为1.21%,与常规回流提取法相比优势明显。     

蛇床子中蛇床子素的提取工艺研究

采用乙醇加热回流法提取蛇床子中的蛇床子素,对提取工艺进行优化。结果表明,最佳工艺条件为:提取液为75%乙醇溶液,用量为药材的8倍,提取时间为1.5 h和提取温度为80℃。     

Mechanical oil extraction

Competitive pieces of equipment for full-pressing and prepressing oilseeds are described. “Enhanser” machines to treat seeds before solvent extraction considerably increase the capacity of the solvent extraction system.     

亚临界水萃取技术在天然产物提取中的研究进展

较详细地介绍了亚临界水萃取技术的原理、设备、工艺流程、影响萃取效果的因素、在天然产物领域的应用及研究成果.指出了该技术存在的问题,并对其应用与发展前景进行了探讨.     

Comparison of membrane extraction with traditional extraction methods for biodiesel production

Three traditional methods for the refining step in biodiesel production were compared: (i) washing with distilled water; (ii) washing with acid (HCl); and (3) dissolving and extracting in a solvent (hexane or petroleum ether) and then washing with distilled water. Biodiesel with a high purity (97.5%) could be obtained by all three methods, but serious emulsification occurred during the refining processes, which led to high refining losses. A novel refining method was developed by using hollow fiber membrane extraction, and polysulfone was selected as the most suitable membrane. This process effectively avoided emulsification during refining and decreased the refining loss. The purity of the biodiesel obtained was about 99%; and other properties, such as density, kinematic viscosity, water content, and acid value, conformed to the standards.