Comparison of the determination methods for total flavonoids in Manilkara zapota leaves

摘要

Al(NO_3)_3-NaNO_2-NaOH, boric acid-citric acid, and AlCl_3 colorimetric assays were compared to determine the total flavonoids in Manilkara zapota leaves. The results indicated that Al(NO_3)_3-Na-NO_2-NaOH colorimetric assay was the most appropriate for the determination of total flavonoids in Manilkara zapota leaves. The stability, precision, and repeatability were very good, with the RSD being 1.94%, 1.22%, and 1.36%, respectively. The content of total flavonoids in Manilkara zapota leaves was 12.38%. The method is appropriate for the quantitative determination of total flavonoids in Manilkara zapota leaves and their preparations.