Organosulfur and phenolic content of garlic (Allium sativum L.) and onion (Allium cepa L.) and its relationship with antioxidant activity

Abstract

Garlic and onion have a role in decreasing risks of chronic diseases due to their antioxidant activity. These biological effects have been attributed in part to organosulfur and flavonoid compounds present in Allium. The aims of this work were to determine the content of total polyphenols, flavonoids and thiosulfinates in garlic and onion cultivars from different origins, their phenolic profile and to evaluate their respective antioxidant activity and the relation of these compounds with the antioxidant capacity. Phenol and flavonoid content and antioxidant activity variability was found among different cultivars. Phenol content was highly associated with the antioxidant activity in onion. While, organosulfur compounds were highly associated with the antioxidant activity in garlic, the variability found in phenol and thiosulfinate content, and antioxidant activity between and within garlic and onion cultivars, would facilitate the selection of cultivars with therapeutic benefits.