The purpose of this paper is to determine the antioxidant properties (capacity and component) of four non‐leafy vegetables. The correlation between the antioxidant capacity and its components of the studied vegetables was also assessed.
Winged beans, also known as four‐angled bean (Psophocarpus tetragonolobus), French bean (Phaseolus vulgaris), string bean (Vigna sinensis) and snow pea (Pisum sativum) were selected as samples from among the common non‐leafy vegetables consumed by Malaysians. These fresh vegetables were lyophilised and ground and their ethanolic extracts were prepared for antioxidant capacity assays and total phenolic, β‐carotene and ascorbic acid contents.
Among the vegetables, string beans showed the highest antioxidant capacity compared to the other vegetables studied (p < 0.05). The total phenolic, ascorbic acid and β‐carotene contents of snow peas were significantly higher (p < 0.05) than the other vegetables. There was a significant positive correlation between scavenging activity and antioxidant components studied. On the other hand, a negative correlation was found between antioxidant activity and its components of the studied vegetables.
Previous reports have indicated that vegetables contain high levels of antioxidants. However, data on antioxidant capacity of these non‐leafy vegetables are still lacking. This research paper shows the non‐leafy vegetables studied is a promising source of antioxidants with good antioxidant capacity. Beside that, along with the studied antioxidant components, other compounds in these vegetables could also contribute to their antioxidant capacity.
