共查询到18条相似文献,搜索用时 187 毫秒
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通过正交实验确定超声波提取藤茶中总黄酮的最佳工艺条件,用柱层析-重结晶法从藤茶中分离得到二氢杨梅素。选用L-酪氨酸、L-多巴为底物,分别测定二氢杨梅素对酪氨酸酶的单酚酶、二酚酶的抑制率。结果表明,提取的最佳工艺条件:提取溶剂是体积分数为60%的乙醇,料液比1∶30(g/mL),提取温度40℃,提取时间40 min,总黄酮得率为46.54%。柱层析-重结晶法分离纯化得到的二氢杨梅素得率为41.12%,纯度为99.12%。二氢杨梅素对单酚酶、二酚酶均有显著的抑制作用,抑制率分别可达95.87%,69.01%。 相似文献
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研究了微波辅助提取银杏叶萜类内酯的工艺.对辐射时间、微波功率、乙醇浓度和液固比进行单因素考察,根据考察结果进行正交实验设计,然后进行验证实验,并将该工艺条件与传统加热回流提取方式进行比较.结果表明,微波辅助提取银杏叶萜类内酯的较佳工艺为:辐射时间为8 min,微波功率为500 W,乙醇浓度为70%,液固比为20:1,此条件下萜类内酯提取率可达1.620 mg·g~(-1).与传统加热回流提取相比,微波辅助提取得到的萜类内酯提取率高出31%,溶剂用量减少33%,提取时间大大缩短.该方法是一种较为理想的银杏叶萜类内酯提取方法. 相似文献
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Ioana Asofiei Ioan Calinescu Adrian Trifan Iulia Gabriela David 《Chemical Engineering Communications》2016,203(12):1547-1553
Extraction of polyphenols from sea buckthorn leaves using microwave-assisted extraction (MAE) is described. The influence of different parameters on the extraction process (reactor type, stirring rate, extraction time, temperature, ethanol/water ratio) was studied. The polyphenolic extracts were analyzed in order to determine the total phenolic content (TPC) either by the Folin–Ciocalteu method or by differential pulse voltammetry (DPV), and the concentration of the main polyphenolic compounds by high-performance liquid chromatography (HPLC). The specific microwave energy was also determined. MAE resulted in a shorter extraction time (7.5 versus 30 min for the conventional method). The best results for MAE were obtained at a temperature of 90°C, using a solvent/plant ratio of 20/1 and 50% ethanol in the extraction solvent. The highest values of antioxidant capacity were obtained for polyphenolic extracts resulted from microwave extraction. 相似文献
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微波-超声波协同萃取银杏黄酮的工艺研究 总被引:4,自引:0,他引:4
以银杏叶为材料,研究了乙醇浓度、微波功率、微波处理时间、料液比、银杏叶粉碎颗粒大小以及微波-超声波协同作用对银杏黄酮提取效率的影响。结果表明微波处理,微波-超声波协同处理可以显著提高银杏黄酮的提取率。确定了最佳的微波处理条件:70%乙醇为萃取液,料液比1∶20,粉末颗粒80目,微波功率50W,微波处理时间4 m in,处理后水浴回流提取2 h所得提取液的黄酮提取率达到81.76%,比直接水浴提取提高了1.3倍,微波-超声波协同处理的黄酮提取率达到83.54%。 相似文献
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三明产柿叶总黄酮的微波提取研究 总被引:1,自引:0,他引:1
采用微波法提取柿叶中总黄酮,探讨了乙醇质量浓度、微波辐射功率、固液比和微波辐射时间等因素对柿叶总黄酮提取率的影响,并用UV和FTIR对提取产物进行了表征.通过单因素实验和正交实验确定最佳提取条件为:乙醇质量浓度65%,固液比1∶ 25(g:mL),微波辐射功率300 W,微波辐射时间15 min(间歇作用5次,每次3 ... 相似文献
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以提取物产率及其对酪氨酸酶的相对抑制率为评价指标,进行了微波辅助提取牡丹皮中酪氨酸酶抑制剂的工艺研究。得到了最佳提取工艺条件:牡丹皮粒度为0.45 mm,以体积分数为70%的乙醇为提取剂,乙醇与牡丹皮的质量比为8∶1,微波450 W提取6 min,重复提取2次。提取液经活性炭脱色、真空浓缩、真空干燥后得浸膏,产率约22.8%,对酪氨酸酶的相对抑制率为82.8%。与直接加热提取法进行了比较,结果表明,微波辅助提取时间由90 min缩短至6 min,提取物产率由19.7%提高至22.8%,对酪氨酸酶的相对抑制率由77.2%提高至82.8%。 相似文献
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《分离科学与技术》2012,47(4):995-1006
Abstract Rubia cordifolia is a common traditional Chinese medicine (TCM) used for centuries for the treatment of cough, inflammation of the joints, uterine hemorrhage, and uteritis. Mollugin is a major active component present in R. cordifolia and recognized as a potential anti-tumor compound. In this work, a microwave-assisted extraction (MAE) method has been developed for extracting mollugin from R. cordifolia. Several variables that can potentially affect the extraction yield, namely extracting solvent, microwave power, extraction time, and solid-liquid ratio were optimized. The separation and quantitative determination of mollugin was carried out by HPLC with UV detection at 254 nm. Under appropriate MAE conditions, such as extraction time of 4 min, ethanol concentration of 70% (v/v), microwave power of 460 W, and solid-liquid ratio of 1:20 (g/mL), the extraction yield of mollugin from R. cordifolia with MAE was higher than conventional extraction methods such as Soxhlet extraction, heat reflux extraction, and ultrasonic-assisted extraction. Due to the considerable saving in time and its higher extraction yield, the proposed MAE procedure was obviously a more rapid and effective sample preparation technique. 相似文献