Phytochemical and Biological Investigation of Thunbergia grandiflora

Abstract

Investigation of 70% aqueous methanol of Thunbergia grandiflora Roxb leaves extract (Family Acanthaceae) led to isolation of ten compounds; Caffeic acid (1), Quercetin-3-O-rutinoside-7-O-I±-L- rhamnopyranoside (2), Kaempferol-3-O-I±-L-rhamnopyranosyl-7-O-I²-D-4C1-arabinopyranoside- 4'-methyl ether (3), Kaempferol-6-C-sophoroside (4) Kaempferide 3-O- E‘-L-arabinofuranoside (5), Kaempferol-3-O-I±-L-rhamnopyranoside (6), isoquercetrin (7), Quercetrin (8), Quercetin (9) and Kaempferol (10) for the first time. The isolated compounds were identified by using spectroscopic techniques as UV,-ESI/MS, 1H-NMR and 13C-NMR. Aqueous methanol extract of Thunbergia grandiflora Roxb leaves exhibited marked hypoglycemic activity comparable to metformin as reference drug and antioxidant activity that was evaluated by glutathione and DPPH radical scavenging activity methods in comparison with vitamin E, as well as hepatoprotective effect to liver damaged rats using CCl4 and compared with silymarin as reference drug.