Extraction of anthocyanin and analyzing its antioxidant properties from different onion (Allium cepa) varieties

Abstract

Onion waste is a renewable raw material rich in different molecular species of antioxidant compounds. To utilize this source as a raw material an environmentally sustainable procedure has been developed for the extraction of anthocyanin and to analyze its antioxidant properties. Three (Red, Small, Big) varieties of onion (Allium cepa) were studied for their total phenol contents, total flavanoid content, total anthocyanin content and antioxidant activities. The data represented in this study demonstrated that the amount of phenolic compound and anthocyanin content differ significantly between 3 varieties of onion peel, and determine the free radical scavenging activity of onion peel. The anthocyanin and phenol content were found to be high in red onion variety when compared to other two varieties. The unutilized outer layer of onion varieties were found to be a rich source of anthocyanin and significant antioxidant properties. The onion peel which is considered as waste can be used as a rich source for anthocyanins and antioxidants.