Effect of hydrolysis on the yield of hederagenin and High-performance thin-layer chromatography densitometric quantification of hederagenin in fruit pericarp of Sapindus spp

Fruit pericarp of Sapindus species are reported to contain glycosides with hederagenin as an aglycone. To free the aglycone from the glycosides, they need to be hydrolyzed, and the commonly used method is hydrolysis with either hydrochloric or sulfuric acid. In the present work, we studied the effect of hydrolysis on the yield of hederagenin from the fruit pericarp of 3 species of Sapindus, viz., S. mukorossi, S. laurifolius, and S. emarginatus. A high-performance thin-layer chromatography densitometric method for the quantification of hederagenin was developed and validated. It involved automated application of samples as bands onto silica gel 60F254 plates, development with toluene-ethyl acetate-formic acid (7 + 3 + 5, v/v/v) mobile phase, detection with anisaldehyde-sulfuric acid reagent, and scanning at 595 nm. The yield of hederagenin ranged from 0.035 to 1.29% (w/w) with different methods of hydrolysis. Hydrolysis with 3.5 M aqueous sulfuric acid under reflux for 6 h gave the maximum yield of hederagenin in all 3 species, with the highest amount in S. emarginatus (1.29%, w/w).