**4.1 Antioxidant effects**

Anthocyanins act as good free radical scavengers due to the keto group with a conjugated double bond. The high reactivity and instability of aglycones in their structure provides an advantage for anthocyanins in acting as antioxidant agents [61]. Glycosylation reactions reduce and diacylation reactions increase their free radical scavenging activity. Anthocyanins have been investigated in various systems and models for their antioxidant effect. In a study investigating the formation of malondialdehyde after UVB irradiation, delphinidin-3-glucoside and pelargonidin-3-glucoside exhibited significant antioxidant effects [62]. Pelargonidin acts as an excellent hydroxyl radical scavenger, and delphinidin acts as a good oxygen radical scavenger. Studies also report cyanidin and cyanidin-3-glucoside to possess inhibitory effects against oxidation of low-density lipoproteins (LDL) [63].
