Natural Antioxidants: Piper sarmentosum (Kadok) and Morinda elliptica (Mengkudu).

The antioxidant activity of two edible medicinal plants commonly used in Malaysian traditional medicine i.e. Piper sarmentosum (kadok) and Morinda elliptica (mengkudu) were tested for antioxidant activity. The methanolic leave extracts of kadok and mengkudu, at 250ug/ml, were tested using the Xanthine/Xanthine Oxidase (X/XOD) Superoxide Scavenging assay. Both extracts showed high superoxide scavenging assay, 88% and 80% respectively compared to superoxide dismutase (SOD) standard. The crude extracts were further fractionated using column chromatography and tested for superoxide scavenging activity, to obtain antioxidant active fractions. Two active fractions were obtained from kadok, PsFr6-71.3%, PsFr7-71.3%, and one active fraction from mengkudu, MeFr3-86.6%. These active fractions were compared against 14 phenolic compound standards. After a series of HPLC analysis of samples and standards, a natural antioxidant compound was identified in kadok and mengkudu i.e. Naringenin (4',5,7-Trihydroxyflavanone) with 75.7% superoxide scavenging activity. Naringenin is a highly potent natural antioxidant that has been reported in the raw materials of larch and grapefruit extracts. Thus, kadok and mengkudu which contain Naringenin, could be used as antioxidant dietary supplements.