Jyotsana Singh, Vinti Singh, Surabhi Shukla and Awadhesh K Rai
Cucurbits are major economically important species of plants; particularly those with edible fruits having nutritional significance. The present work was to investigate the polyphenolic content and antioxidant capacity of peels and pulps of four cucurbit fruits, namely pumpkin, ash gourd, watermelon and muskmelon. The solvent systems used were methanol, ethanol and acetone at three different concentrations in distilled water (50, 70, and 100%) and 100% distilled water. The extracts were analyzed for their total phenolic content, total flavonoid content and antioxidant activities using Ferric Reducing Antioxidant Power assay (FRAP assay), DPPH free radical-scavenging assay and ABTS radical scavenging capacity. The result showed that the highest extraction was by 50% acetone in case of peels and 50% ethanol in case of pulp. The best solvent was 50% acetone as it gave highest yield as well as showed highest correlation between various assays. The polyphenolic content and the antioxidant activity were high in peels than pulps. The muskmelon fruit extracts (peel and pulp) showed highest antioxidant activity. High polyphenolic content showed significant correlation with high antioxidant activity. The result indicated that these cucurbit fruit are good source of natural antioxidants which can be utilized as an ingredient to functional foods.