Estimation of Apigenin, an Anxiolytic Constituent, in Turnera aphrodisiaca

An HPTLC densitometric method has been developed to estimate apigenin in Turnera aphrodisiaca aerial and its segregated parts (leaves, stems, flowers and fruits) so that plant can be standardized on the basis of its bioactive marker. The apigenin content in methanol extract of T. aphrodisiaca aerial parts was found to be about fourteen times less than acid hydrolyzed methanol extract of the plant indicating the presence of most of apigenin in glycosidic form. Amongst different plant parts, flowers possessed maximum content of apigenin followed by leaves. The apigenin content was also determined in three marketed formulations of T. aphrodisiaca viz., NLK, DWSG and SBL. DWSG contained higher content of apigenin. Aerial parts of the plant were collected at bimonthly intervals over a period of one year in the months of January, March, May, July, September and November. The plant material collected in September showed maximum content of apigenin.