A new cyclohexenone (1) and a new caffeoyl ester derivative (2), together with the known compounds (-)-isolariciresinol 3-alpha -O-beta -D-glucopyranoside (3), (+)-1-hydroxypinoresinol 1-O-beta -D-glucopyranoside (4), isoacteoside (5), luteolin 4'-O-beta -D-glucopyranoside (6), and indole-3-carboxylic acid (7), were isolated from the leaves of Bauhinia tarapotensis. The structures of these new compounds were determined by spectroscopic data analysis. The antioxidant activities of 1-7 were determined by measuring their free radical scavenging effects, using the 1,1-diphenyl-2-dipicrylhydrazyl free radical (DPPH) and Trolox equivalent antioxidant activity (TEAC) methods, and the coupled oxidation of beta -carotene and linoleic acid. Compounds 3-5 showed good activities in the DPPH and TEAC tests, while compounds 1 and 2 were active in the coupled oxidation of beta -carotene and linoleic acid bioassay.
Antioxidant Principles from Bauhinia tarapotensis
BRACA, ALESSANDRA;DI BARI, LORENZO;MORELLI, IVANO
2001-01-01
Abstract
A new cyclohexenone (1) and a new caffeoyl ester derivative (2), together with the known compounds (-)-isolariciresinol 3-alpha -O-beta -D-glucopyranoside (3), (+)-1-hydroxypinoresinol 1-O-beta -D-glucopyranoside (4), isoacteoside (5), luteolin 4'-O-beta -D-glucopyranoside (6), and indole-3-carboxylic acid (7), were isolated from the leaves of Bauhinia tarapotensis. The structures of these new compounds were determined by spectroscopic data analysis. The antioxidant activities of 1-7 were determined by measuring their free radical scavenging effects, using the 1,1-diphenyl-2-dipicrylhydrazyl free radical (DPPH) and Trolox equivalent antioxidant activity (TEAC) methods, and the coupled oxidation of beta -carotene and linoleic acid. Compounds 3-5 showed good activities in the DPPH and TEAC tests, while compounds 1 and 2 were active in the coupled oxidation of beta -carotene and linoleic acid bioassay.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.