Bioactive Compounds and Antioxidant Potential of Food Industry By-products in Egypt

Abstract

The present study was carried out to examine the bioactive compounds and antioxidant potential of four food industry by-products (potato peel, cauliflower leaves, onion skin and mango peel) in Egypt. The total dietary fiber content for all tested by-products was ranged 27.15-42.71 g.100g-1, total carotenoids was 92.43- 412.14 mg.100g-1 and total phenolics was 1104-7129 mg GAE.100 g-1. The mango peel powder (MPP) was recorded the highest content of total dietary fiber and total carotenoids while red onion skin powder (ROSP) recorded the highest values of total phenolics. The food by-product extracts showed considerable differences in antioxidant activity when it was calculated by the four different methods used in this study. The antioxidant value (AOX, A/h), antioxidant activity (AA,%), oxidation rate ratio (ORR) and Antioxidant activity coefficient (AAC) were ranged 0.017-0.106, 81.23-96.98, 0.030-0.187 and 584.46-858.27, respectively. ROSP showed strong antioxidant activity followed by MPP, PPP and CLP, respectively. Correlation analysis indicated that there were a strong positive significant relationship (r2 = 0.741-0.962, p≤ 0.01) between total phenolics content and antioxidant activity and a positive significant relationship (r2 = 0. 604-0.718, p≤ 0.05) between total carotenoids content and antioxidant activity in all tested by-products. These correlations confirm that phenolic compounds mainly with carotenoids partially are responsible for the antioxidant activity of the tested by-products. In conclusion, data of the present study revealed that food industry by-products can be good sources of valuable bioactive compounds and antioxidants subsequently extend their potential uses in nutritional and therapeutic applications.