Antioxidant activity and HPTLC profile of Lagenaria siceraria fruits

Abstract

The fruits of Lagenara scerara Standl. (Cucurbitaceae) are widely used for medicinal and nutritional purposes in Africa. The health promoting ability of the fruits might be related to antioxidant properties of its constituents. In this study the antioxidant effect of fresh and dried fruits of L. scerara was evaluated by comparing the 2,2-diphenyl-1,1-picrylhydrazyl (DPPH) radical scavenging and reducing capacity of ethyl acetate and n-butanol extracts of fresh and dried fruits. The comparison was further emphasized by high performance thin layer chromatography (HPTLC) analysis of the extracts so as to relate activities with their chemical profiles. Results indicated that ethyl acetate (EA) extract of the fresh fruits exhibited higher DPPH radical scavenging activity than other samples. At 0.01 mg/ml the order of activity was: EA dried fruits (50.6%) < Bt (n-butanol) fresh fruits (53.3%) < Bt (n-butanol) dried fruits (64.8%) < EA fresh fruits (68.6%) < Bt dried fruits (71.8%) ≤ Bt fresh fruits (72%) < EA fresh fruits (81.6%) < Gallic acid (88.5%). In the reducing capacity assay, Bt fresh fruits extract exhibited higher reducing power than all test samples. The HPTLC chemical profiles of both fresh and dried fruit extracts showed some slight differences. The slight differences in antioxidant activities were justified by the HPTLC chemical profiles of the fruits. Therefore, taking fresh or dried fruits of L. scerara may relatively give similar antioxidant effects. Since the fruits of this plant matures in bulky, then drying, milling and packing the products under hygiene environment can ensure a constant supply of antioxidant supplement. _______________________________________________________________________________________