Isolation of antibacterial activity constituents of total flavonoids from sophora flavescens and simultaneous determination of seven flavonoids by HPLC / 中国药学杂志

ABSTRACT

OBJECTIVE: To study the chemical constituents of the total flavonoids from Sophora flavescens and establish a method for simultaneous determination of seven compounds. METHODS: The compounds were isolated by chromatography on silica gel and ODS column and their structures were elucidated by spectroscopic analysis. The samples were analyzed on a Dikma C18 column (4.6 mm × 250 mm, 5 μm) ; gradient elution was performed using mobile phase composed of methanol (A) and water (B); the detection was carried out using a photodiode array detector at 280 nm. RESULTS: Seven compounds were isolated and their structures were identified as kuratidine (1), sophoraflavanone G (2), kurarinone (3), isoanhydroicaritin (4), isoxanthohumol (5), formononetin (6), and trifolirhizin (7). The calibration curve was linear within 8.70-87.00, 44.25-442.50, 128.10-1 281.00, 9.40-94.00, 48.40-484.00, 14.20-142.00, and 25.70-257.00 μg·mL-1 for kuraridine, sophoraflavanone G, kurarinone, isoanhydroicaritin, isoxanthohumol, formononetin, and trifolirhizin, respectively (r > 0.999 0), and the extraction recoveries varied from 95% to 105%. CONCLUSION: The main chemical components contributing to antibacterial activity of total flavonoids may be sophoraflavanone G, kurarinone, and isoxanthohumol. The method is simple, rapid, accurate, and can be used simultaneously to determine the contents of the seven active ingredients.