Antioxidant and phenolic constituents of Hypoxis Colchicifolia

Abstract

Hypoxis colchicifolia is extensively used in traditional medicine in Southern Africa. Providing a rationale and indicating the toxicity of the plant is essential for its future use as a natural therapeutic agent. In this study H. colchicifolia corm and leaf extracts were qualitatively assessed for phytochemical constituents and total phenolic content. The antioxidant potential of the extracts was evaluated using the 1,1-Diphenyl-2- picryl-hydrazyl assay, 2,2′-azinobis-(3-ethylbenzothiazolline)-6-sulfonic acid assay, phosphomolybdenum assay, cupric ion reducing capacity assay and the ferric reducing antioxidant power assay. All extracts indicated the presence of key phytochemical constituents and no toxicity. The extracts showed good antioxidant potential against various free radicals. Most extracts exhibited a lower IC50 than that of the positive control (rutin) against free radicals, thus indicating the good antioxidant potential of the extracts. The extracts of leaves and corms cannot be used interchangeably due to differences in the phytochemical composition. Acetone and methanol extracts show the most favorable results demonstrating the solvents’ effectiveness in the phytochemical extraction of H. colchicifolia. The study also sheds light on the use of H. colchicifolia leaves as a natural alternative, which has not been previously explored. The H. colchicifolia extracts exhibit promising antioxidant potential, validating their use as a tonic for good health.