Abstract

Phenols, a major group of antioxidant phytochemicals, have profound importance due to their biological and free radical scavenging activities. To identify their potential sources, extracts of some underused fruits (Muntingia calabura, Averrhoea bilimbi and Artocarpus altilis) were assessed with regard to their total phenolics and flavonoid content, as well as antioxidant activity in different solvent systems (methanol, ethanol and acetone) and distilled water. The phenolics and flavonoid content of M. calabura was 1.356 to 3.872 mg tannic acid equivalents/g fresh weight (TAE/g fw) and 0.026 to 0.068 mg rutin equivalents/g fresh weight (RE/g fw), respectively. That of A. bilimbi was 0.581 to 1.334 mg TAE/g fw and 0.021 to 0.037 mg RE/g fw, and that of A. altilis was 0.689 to 1.723 mg TAE/g fw and 0.013 to 0.043 mg RE/g fw. The extracts were also found to have significantly different levels of antioxidant activities. A correlation between antioxidant activity and phenolic content was observed, which shows that the tested plant extracts are having potential antioxidants of natural origin.

Key words: Phenolics, flavonoids, antioxidants, Artocarpus altilis, Averrhoea bilimbi, Muntingia calabura.