EXTRACTION AND EVALUATION OF BIOACTIVE COMPOUNDS FROM SOME FRUIT AND VEGETABLE PEELS

Abstract

Different research reports have revealed that food industry by-products can be considered as good sources of potentially valuable bioactive compounds. This study was performed to evaluate the antioxidant capacity of the peel extracts of pomegranate (PoP), mango (MaP), prickly-pear (PrP), Cantaloupe (CaP) and pea (PeP) using different solvent polarity (methanol, ethanol, ethylacetate and water) to particular attention to their content of total phenolics and flavoniods. Among all tested extracts, ethanolic extracts of PoP, MaP and PrP and aqueous extract of CaPand PeP were shown to exhibited a significant (p≤0.05) highest extraction yield, total phenolic and flavonoid contents and antioxidant capacity (measured by DPPH,ABTS and FRAP methods). The antioxidant capacity of different peel extracts was showed the following descending order, MaP>PoP>PrP>CaP≈ PeP. Also there was a strong positive correlation between the DPPH, ABTS, FRAP values and total phenolic as well as, flavoniod contents of different peels extracts. Seventeen phenolic compounds were identified and quantified by HPLC-UV analysis in different peel extracts. Galic acid was identified as the major compound in MaP and PoP extracts, while it was rutin in the case PrP,CaPand PeP extracts. From the results obtained, fruit and vegetable peels can be considered as good sources of valuable bioactive compounds.