Phytochemicals and bioactivity of Piper porphyrophyllum N. E. Br. and Piper sarmentosum Roxb.

Abstract

Chemical investigations of Piper porphyrophyllum N. E. Br. and Piper sarmentosum Roxb. have been carried out. The stems of P. porphyrophyllum and the whole plant of P. sarmentosum, each were extracted by maceration using petroleum ether, dichloromethane, ethyl acetate and methanol consecutively. Purification of the crude extracts was carried out using several chromatographic techniques. The structures of the pure compounds were elucidated by spectroscopic methods such as IR, 1D (1H, 13C, DEPT) and 2D (COSY, HMQC, HMBC) NMR and GC-MS. Four compounds have been identified from the petroleum ether extract of P. Porphyrophyllum and were characterized as ß-sitosterol, sesamin, N-isobutyl-15- (3’,4’-methylenedioxyphenyl)-2E,4E,12E-pentadecatrienamide and a new compound, 5-hydroxy-7,2’,4’,6’-tetramethoxyflavone. Meanwhile, 5,7,3’,4’,5’- pentamethoxyflavone was identified from the dichloromethane extract. Four compounds were isolated from P. sarmentosum. The petroleum ether extract afforded 3’,4’-methylenedioxyphenyl-13-tetradecene while the dichloromethane extract gave asaricin and 2-(methyl-2’-propenoate)-4,5- methylenedioxybenzaldehyde. Purification of the methanol extract gave 4-(2’- octenyl)phenol. Pure compounds which were isolated abundantly were screened for cytotoxic study using methylthiazol tetrazolium (MTT) cell proliferation assay. 4- (2’-Octenyl)phenol was found to have the highest cytotoxic effect towards the cell with the percentage of cell inhibition of 12.96%.