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海南蒲桃叶黄酮的提取及抗氧化性研究 总被引:2,自引:0,他引:2
采用正交试验法研究了海南蒲桃叶黄酮提取条件对黄酮得率的影响,确定了最佳提取条件为:乙醇体积分数70%,料液比1:20(g:mL),提取温度80℃提取3 h,此条件下黄酮得率为6.06%。利用体外试验检测不同浓度海南蒲桃叶黄酮对二苯基苦基苯肼DPPH·的清除作用。结果表明海南蒲桃叶黄酮是一种有效的自由基清除剂,对DPPH·有显著的清除作用。黄酮溶液质量浓度在31.25~250m g/L范围内,清除率随质量浓度增大而增大,最高可达93.04%。 相似文献
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采用乙醇浸提法从橘子皮中提取黄酮,通过正交试验确定提取的最佳条件为:70%乙醇为提取剂,固液比为1︰20(g/mL),提取温度是70℃,提取时间2h,在510nm处测定橘黄酮质量浓度为0.205g/L,从橘子皮中提取的黄酮干重得率为2.938mg/g。本实验探究橘黄酮的抑菌活性,采用牛津杯法测抑菌作用,结果表明,橘黄酮对金黄色葡萄球菌、大肠杆菌、黑曲霉、灰葡萄孢菌和黄枝孢菌均有抑制作用,铜和镁离子可分别增强橘黄酮对细菌和真菌的抑菌作用,低pH和低温可提高抑菌效果,且优化pH和温度的橘黄酮剂型降低了最小抑菌浓度(MIC)20%,对金黄色葡萄球菌、大肠杆菌、黑曲霉、灰葡萄孢菌和黄枝孢菌的抑菌作用分别提高了17%、27%、25%、28%、19%,高于对氯间二甲苯酚和甲基托布津的抑菌作用,特别是高于对细菌的抑菌作用。 相似文献
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为获得最佳的荞麦粉黄酮超声提取工艺,在考察单因素的基础上,采用四因素三水平的正交试验,获得最佳的超声提取黄酮工艺条件为:乙醇浓度65%,料液比为1∶45,超声温度60℃,超声时间25 min。在最优工艺条件黄酮得率最高,为20.5 mg/g。 相似文献
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采用果胶酶酶解预处理与乙醇浸提相结合提取工艺从决明子中提取总黄酮。以芦丁为对照品,采用紫外可见分光光度法,在波长510nm处测定决明子中总黄酮含量;在单因素实验基础上,通过正交试验得出决明子中总黄酮的最佳提取工艺条件为:酶解温度30℃,酶用量2mg,酶解pH3.0,酶解时间0.5h,乙醇用量35mL,乙醇浓度70%,最佳提取工艺条件下总黄酮提取率达2.03%。酶解-溶剂提取法是一种安全高效的提取方法,可用于决明子中总黄酮的提取。 相似文献
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A new salting-out extraction method, namely chelatometric salting-out extraction, was established for rapidly extracting flavonoids from Folium nelumbinis. Borax was used as a chelating agent and an ethanol/K2HPO4 system as the salting-out extraction system. The maximum flavonoid concentration in the top phase was observed at an ethanol concentration of 43.0% and an amount of salt of 2.45 g under the experimental conditions. The pH value of the system and extraction time had no obvious influence on the extraction efficiency of flavonoids. The results also showed that the extraction efficiency of flavonoids exceeds 90.4% at the first time extraction. Moreover, the antioxidant activities of flavonoids were evaluated by DPPH? radical assays. 相似文献
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采用微波辐射技术,以乙醇提取苹果渣中黄酮类化合物。考察了乙醇浓度、微波功率、处理时间、料液比和浸泡时间对总黄酮提取率的影响。结果表明,最佳工艺条件为:70%乙醇,微波萃取2 min,微波功率为350 W,料液比1∶30(g/mL),总黄酮1次提取率0.683 7%。 相似文献
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大孔吸附树脂精制鱼腥草黄酮类化合物 总被引:5,自引:0,他引:5
Flavonoids are one main kind of effective components in Houttuynia cordata Thunb., which display a wide range of pharmacological activity. In this study supercritical fluid extraction (SFE) with carbon dioxide was first used as preparat ion step to remove the volatile components, which are also active components, from Hout-tuynia cordata Thunb. Then ultrasound-assisted extraction was used to obtain the crude flavonoids and the macro-porous resin adsorption technology was further employed to purify the flavonoids. Nine kinds of macroporous resins with different properties were tested through static adsorption, and one macroporous resin labeled as D101 was selected. The effect of several factors, such as the ratio of column height to diameter, initial concentration and pH, on both flavonoids yield and content were explored by dynamic adsorption to obtain reasonable conditions of adsorption and desorption. The experimental results show that the content of fiavonoids can be above 60% with fia- vonoids recovery of 93.3 % under the optimum conditions of purification. HPLC analysis of the final flavonoids product shows it contains quercitrin, hypefin, rutin and quercetin. 相似文献
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