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

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.