共查询到19条相似文献,搜索用时 93 毫秒
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以香蕉皮为材料,丙酮溶液为溶剂,考察丙酮浓度、浸提温度、浸提时间和料液比对香蕉皮单宁提取效果的影响,利用正交实验对单宁的提取工艺进行优化。结果表明,影响单宁提取效果的主次因素顺序为:料液比﹥丙酮浓度﹥提取时间﹥提取温度,最佳工艺条件为:丙酮浓度为50%,料液比为1∶12 g/m L,提取温度为50℃,提取时间为2 h。 相似文献
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研究微波预处理-溶剂回流提取马占相思叶多酚的工艺条件。以干马占相思叶粉为原料,用正交实验法对马占相思叶总多酚的微波预处理提取工艺进行优选,考察预处理乙醇浓度、固液比、微波处理时间对马占相思叶总多酚提取量的影响。结果表明,微波预处理溶剂回流提取马占相思树叶总多酚的最佳工艺参数为:润湿乙醇浓度为50%,用量为样品量的2倍,在微波功率800 W条件下处理30 s后,用体积分数70%乙醇在料液比1∶7,水浴温度70℃、自然pH值(pH=6.38)浸提条件下回流提取30 min。在此工艺条件下,可提取总多酚18.013 mg/g马占相思树叶,所得的多酚提取物以总多酚计的清除DPPH自由基的IC50值为39.126 g DPPH/g总多酚。 相似文献
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从沙田柚皮中提取精油的工艺研究 总被引:9,自引:0,他引:9
为了综合利用沙田柚皮,进行了从沙田柚果皮提取精油的研究,通过实验筛选,得到了柚皮精油提取的最佳工艺条件:采用石油醚为提取溶剂,m(石油醚):m(柚皮)=24:1,回流提取两次,每次提取60min。提取液进行真空浓缩,得精油粗产品。往精油粗产晶中加入乙醇溶解.放入-5℃冰箱中冷冻过夜,抽滤,滤液进行真空浓缩,即得精油,产率约1.96%。φ(精油)=99.2%。实验得到的柚皮精油为独特柚子香味的黄色油状液体,难溶于水,易溶于乙醇等有机溶剂,物理参数为:相对密度d20^20=0.857,旋光度为a= 97。折光率n=14765. 相似文献
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《应用化工》2022,(10)
分别采用离子交换树脂法和酸提法提取香蕉皮果胶。利用Fick第二定律构建动力学模型,获得速率常数和表观活化能E_a,且进行了有效性分析和模型预测能力验证。结果表明,构建的动力学模型均能较好的预测离子交换法和酸提法提取香蕉皮中果胶的动力学过程,离子交换法提取果胶的最优条件:树脂用量7%,料液比1∶20 g/mL,浸提液pH值为2,浸提温度85℃,浸提时间为T_(max)=118.9 min,果胶得率达19.29%;酸提法在相同料液比、浸提液pH值条件下,浸提温度85℃,浸提时间为T_(max)=120.1 min,果胶得率为10.58%。离子交换法提取香蕉皮中果胶的活化能与传统的酸提法相比,E_a从37.88 kJ/mol降至23.68 kJ/mol,离子交换法提取香蕉皮中果胶明显优于酸提法。 相似文献
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Tangerine peel, a very abundant natural resource, only part of which has been used in traditional Chinese medicine and health foods but most were discarded as the waste, which should be fully utilized. Previous studies showed its functional components include volatiles, ?avonoids, phenolic acids, and pectin, all of which cannot be effectively extracted through traditional methods. A column chromatographic extraction with gradient elution was developed for one-step extraction of all bioactive substances from tangerine peel. Dried material was loaded into a column eluted with 2-fold of petroleum ether: ethanol (7:3, PE) for the volatiles fraction. Sequentially eluted with 4-fold of ethanol: water (5:5, EW) then separated into ?avonoids and polysaccharides by 80% ethanol precipitation of polysaccharides. The third eluted with 5-fold of water and then 60% ethanol precipitation of pectin. Through these procedures, volatiles, ?avonoids, and pectin in tangerine peel were simultaneously extracted at 98% extraction rates and simply separated at higher than 95% recovery rates. To further reduce solvent consumption and the volume of the final extract, cyclic column chromatographic extraction should be used. The method provides a simple and high ef?cient extraction and separation of a wide range bioactive substances. 相似文献
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Ultrasound-assisted extraction followed by adsorption and desorption was performed successively for efficient recovery of polyphenols from ginger rhizome (Zingiber officinale). The maximum degree of extraction was observed in case of methanol (0.55 mg/ml) followed by acetone (0.52 mg/ml) and ethanol (0.37 mg/ml). At optimized conditions, the polyphenol recovery was found to be 19.2 mg. Amberlite XAD4 had shown the highest adsorption capacity (0.89 mg/ml). Kinetic studies indicated the adsorption equilibrium to be about 20 min. Adsorption capacity was achieved at 25 ± 2°C, and adsorption process exhibited exothermic nature. Freundlich isotherm fitted the data well. Ethanol had shown best desorption efficiency (93.44%). 相似文献