Antioxidant Activity in vitro of Total Flavonoids and Total Polysaccharides from Rose Petals

Using VC as a positive control,the antixoidant activities of total flavonoids and total polysaccharides from rose petals collected from Hotan,Xinjiang were evaluated by scavenging rates against DPPH,superoxide anion and hydroxyl radicals and inhibitory rate against lipid oxidation of liver homogenate.Both total flavonoids and total polysaccharides from rose petals had scavenging effects on DPPH,superoxide anion and hydroxyl radicals.Over the studied concentration range,the radical scavenging activity of both extracts showed linear concentration dependence.In DPPH,superoxide anion and hydroxyl radical scavenging assays,the IC50 of the total flavonoid extract were 2.21,2.39 μg/mL and 2.54 μg/mL,respectively,compared to 2.78,2.86 μg/mL and 3.44 μg/mL for the total polysaccharide extract.Moreover,both extracts possessed potent inhibitory effects on lipid peroxidation in a dose-dependent manner,with maximum inhibory rates of 49.87% and 69.52%,respectively.The total flavonoid extract exhibted stronger fradical scavenging activity than the total flavonoid extract despite having anti-lipid peroxidation activity.