Extraction of bioactives from pumpkin by-products and determination of their antioxidant activity

Abstract

Agro-industrial and food processing from pumpkins (Cucurbitaceae) produces a large number of by-products: bark, pomace, seeds still rich in bioactive compounds, especially carotenoids and green pigments (proto chlorophyll (a and b) and proto pheophytin (a and b)), which exhibit a broad spectrum of health-promoting effects and can be used as ingredients in functional food and cosmetics. For extraction of bioactive compounds from dried pumpkin by-products different methods were used: supercritical CO2, Soxhlet extraction with n- hexane, ethanol. Vegetable oils (rapeseed, coconut, grapeseed and olive oil) were used as green solvent alternatives to conventional organic solvents for carotenoid extraction. Detection and analyses of chlorophylls and carotenoids was done with hexane/acetone, cyclohexane, ethanol as solvents. The aim of this study was to use pumpkin by-products for extraction of high-value bioactive compounds with different methods, to determine antioxidant´s content and profile – carotenoids (ß-carotene, lutein, lycopene, zeaxanthin), pigments (chlorophylls a, chlorophylls b) with different solvents and to find out what solvent can be used for detection of pigments and carotenoids; to determine antiradical scavenging activity of biologically active compounds in extracts from pumpkin by-products (peel and hulled seeds).