Six flavonoids from the ethyl acetate extract of the pericarp of Garcinia schomburgkiana

Garcinia is a genus of Clusiaceae, distributed throughout tropical Asia, Africa, New Caledonia, Polynesia, and Brazil. In traditional medicine, the fruits of Garcinia have been utilized in infusions for treating wounds, ulcers, and dysentery. Extracts of the pericarp and seeds of Garcinia have demonstrated antioxidant, anti-inflammatory, leishmanicidal, and antiprotozoal activities. Garcinia plants contained a broad range of biologically active metabolites which, in the last few decades, have received considerable attention due to the chemical compositions of their extracts, with compounds possessing beneficial effects in several diseases. These species provide a rich natural source of bioactive compounds with relevant therapeutic properties and anti-inflammatory effects, such as flavonoid, xanthone, biflavonoid, biphenyl derivaties, and benzophenone. This paper demonstrated the relevance of the genus as a rich source of compounds with valuable therapeutic properties, with potential use in the prevention and treatment of nontransmissible chronic diseases. Phytochemical investigation on the fraction EA4 from the ethyl acetate extract of the pericarp Garcinia schomburgkianna led to the isolation of six flavonoid compounds such as quercetin (1), kaempferol (2), luteolin (3), cirsiliol (4), quercetin 3-O-β-D-glucopyranoside or isoquercetin (5) and quercetin 3-O-α-L-rhamnopyranoside (6). Their chemical structures were elucidated by 1D, 2D–NMR as well as compared with the literatures. Compounds (1), (3), (4), (5), (6). were isolated for the first time from the species Garcinia schomburgkiana collected at Quang Binh province, Vietnam.