New insights into antioxidant activity of Brassica crops

► Brassica antioxidant activity reaches its maximum three months after sowing. ► Kale crop stood out from the rest because of its high antioxidant activity. ► By-products may be employed to obtain derived products with antioxidant activity. ► Phenolic content and composition vary with plant stage and crop. ► Antioxidant activity is related to phenolic content and composition.