微波辐射溶剂提取-分光光度法测定农吉利中的总黄酮

采用微波辐射溶剂法提取农吉利中的总黄酮。研究了微波功率、微波辐射时间、提取溶剂用量、提取温度、提取时间等实验条件。以牡荆素作为目标物表征,利用UV法测定了提取液中总黄酮。实验结果表明:与常规溶剂回流提取相比,在相同的提取条件下用微波辐射处理药材后再进行提取,其提取率明显提高,山东和广西样品中总黄酮的提取率分别提高48.3%和23.2%。该方法的加标回收率为94.2%~105.5%,重复测定结果的相对标准偏差为1.1%(n=6)。该法用于农吉利中总黄酮的提取和测定,处理方法简单,测定结果可靠。

EXTRACTION AND DETERMINATION OF THE TOTAL FLAVONOIDS IN CROTALARIA SESSILIFLORA L.BY MICROWAVE - IRRADIATED REFLUX EXTRACTION

Flavonoids in crotalaria sessiliflora L. was extracted by microwave irradiation - solvent method. Experimental con- ditions such as microwave power, irradiation time, medicinal material to solvent, extraction temperature, extraction time were opti- mized. By using vitexin as the target object, the total flavonoids from the extracting solution were determined by UV spectrophotometry. The results indicated that the extraction yield of total flavonoids in samples from Shandong and Guangxi were incerased by 48.3% and 23.2% respectively, especially after the pretreatment of microwave irradiation of the medicinal material, compared with the convention- al solvent reflux extraction. The recovery of standard addition was 94.2% - 105.5%, and RSD of replicated determination results was 1.1% （ n = 6）. This method has been applied to extract the total flavonoid in crotalaria sessiliflora L successusfully. The results were reliable.