Abstract

We studied supercritical extraction with ethanol-modified CO2, combining different levels of temperature (40 and 60 C) and pressure (20, 30 and 40 MPa), to obtain extracts from Leptocarpha rivularis stalks with inhibitory capacity against a-amylase, an enzyme associated with diabetes mellitus. The extracts were measured for their ability to inhibit a-amylase, and for contents of total flavonoids, catechin and myricetin and caryophyllene oxide. The highest inhibitory capacity against a-amylase was obtained with extract at 60 C and 40 MPa, producing the highest total flavonoids (137.6 mg/g) and caryophyllene oxide (6.28 mg/g) contents. The highest contents of catechin (1.98 mg/g) and myricetin (0.12 mg/g) were obtained at 40 C and 40 MPa. Part of the hypoglycemic mechanism of the extract would be associated with the inhibitory capacity against a-amylase, due to the presence of flavonoids and caryophyllene oxide. (C) 2020 Elsevier B.V. All rights reserved.