Abstract:

Response surface methodology was used to optimize the extraction process for saponins from young leaves
of Salicornia herbacea. The saponions extracted were structurally characterized and evaluated for inhibitory effect on
α-glucosidase and pancreatic lipase in vitro. Our results indicated that the optimal extraction conditions were material-toliquid
ratio of 1:27 (g/mL), ethanol concentration (V/V) of 62%, and ultrasonification time of 30 min. Under these extraction
conditions, maximum yield of saponins of 10.14 mg/g was obtained. Color reaction and infrared spectral analysis showed
that the basic structure of saponins from Salicornia herbacea was tetracyclic triterpene saponin. The purified saponins had a
strong inhibitory effect on both α-glycosidase and pancreatic lipase in vitro in a dose-dependent manner, and the maximum
inhibitory rates were 68.20% and 84.28%, respectively. These results suggest that saponins from Salicornia herbacea may
have similar hypoglycemic mechanism and hypolipidemic effect to acarbose.

Key words: Salicornia herbacea, saponin, response surface methodology, α-glycosidase, pancreatic lipase