酸水解HPLC测定桑叶中槲皮素及山柰酚含量

Acid Hydrolysis Followed by HPLC for Simultaneous Determination of Quercetin and Kaempferol in Folium Mori

关键词:  桑叶  高效液相色谱法  水解  槲皮素  山柰酚  含量测定

Key words:  Folium Mori  HPLC  hydrolysis  quercetin  kaempferol  determination

摘要:

目的 建立桑叶中水解黄酮苷元(槲皮素、山柰酚)的含量测定方法，并考察湖州地区不同品种、不同采摘时间、不同种植基地桑叶中上述成分的含量差异。方法 粉碎的桑叶样品经甲醇-盐酸混合溶液提取水解后，用反相高效液相色谱法，以Zorbax SB C₁₈为分离柱，甲醇-0.2%磷酸(55∶45)为流动相，流速1.0 mL·min^-1，检测波长370 nm。结果 经方法学验证，本方法各项指标均符合中药成分含量测定要求；不同品种、不同种植基地、不同采集时间桑叶中上述2种成分含量均有较大变化；同一基地、同一品种，冬桑叶中上述2成分的含量明显高于其他季节采集的桑叶。结论 水解后经HPLC测定桑叶中槲皮素、山柰酚含量方法可用于桑叶药材质量控制。桑叶中水解槲皮素及山柰酚含量受多种因素影响。

Abstract:

OBJECTIVE To develop an acid hydrolysis followed by HPLC method for determination of quercetin and kaempferol in Folium Mori, and compare the content of these components in Folium Mori from different harvest time, sources and species. METHODS 0.25 g powder of Folium Mori was extracted and hydrolyzed by HCl-methanol mixed solution at 90 ℃ for 2 h. Quantification was performed by HPLC at 35 ℃ using Agilent Zorbax SB-C₁₈ column (4.6 mm×250 mm, 5 μm), methanol-0.2% phosphoric acid (55∶45) was applied as mobile phase and DAD detector was set at 370 nm. RESULTS The results of assay validation were satisfied. The contents of quercetin and kaempferol varied obviously among mulberry leaves from different plant sites, different species, and the contents of the two ingredients of the samples collected in winter were higher than those harvested in other seasons. CONCLUSION The developed hydrolysis/HPLC method is able to quantify quercetin and kaempferol in Folium Mori leaves. The contents of quercetin and kamepferol are influenced by some factors.