微波法提取洋葱总黄酮工艺条件及含量测定

目的:探讨洋葱总黄酮提取工艺并建立洋葱提取物中黄酮类化合物含量测定方法,以充分开发利用洋葱资源.方法:微波辅助处理洋葱,乙醇-水浴提取类黄酮,采用正交试验优化提取工艺,分光光度法定量分析提取物中黄酮含量.结果:微波法提取洋葱黄酮优化工艺条件为料液比1∶15,微波辐射时间15 min,乙醇浓度70%,提取次数3次.方法学考察表明,标准品浓度在0.005 mg/mL~0.06 mg/mL范围内与吸光度有良好的线性关系(A=12.794C-0.0101,R2=0.9997),加样平均回收率为99.15%,经样品显色稳定性分析,最佳测定时间应选择在静置8~12 min时为宜.结论:为洋葱中类黄酮提取工艺的确定和含量测定提供科学依据.

Extraction Technology of Flavonoids in Onion with Microwave-assay and Content Determination

Objective To open and utilize sufficiently the resources of onion,the extracting and measuring technology of the total flavone contents in onion were explored.Methods The orthogonal test was carried out to optimize technological conditions in which flavonoids were extracted using ethanol-water bath assisted-treatment by microwave from onion,and spectrophotometry was employed for the determination of total flavone.Results The optimal extraction conditions obtained were ratios of solid to solvent of 1∶15,microwave time 15min,70% alcohol and extracting 3 times.The methodological study showed that the flavone content had close linear relationship with absorbability when the standard sample concentration was within range of 0.005mg/mL to 0.06mg/mL(A=12.794C-0.0101,R2=0.9997),and the average recovery of adding sample was 99.15%,and the best time of determining sample should be chosen at 8-12min after settled by analyzing the stability of colored sample solution.Conclusion The results may provide some scientific basis for extract processing of flavonoids and content determination in onion.