Antioxidant activities of proanthocyanidins from Chinese bayberry(Myrica rubra Sieb. et Zucc.) leaves in lard oil

The antioxidant activities of proanthocyanidins from Chinese bayberry leaves in lard oil was studied using peroxide value(POV),acid value(AV) and the content of malondialdehyde by Schaal oven-storage test.Induction period was determined by oxidative stability instrument. The results showed that proanthocyanidins from Chinese bayberry leaves had significant inhibitory effect on the POV,AV and the content of malondialdehyde(p <0.05) and could inhibit the oxidation of lard oil. When adding 0.1% proanthocyanidins from Chinese bayberry leaves into the lard oil,the inhibition of oxidation was better than BHT,while was worse than TBHQ,indicating proanthocyanidins from Chinese bayberry leaves had powerful antioxidant activity in lard oil and could prevent the oxidation of oil effectively. Inhibition rates of POV,AV and the content of malondialdehyde were 76%,69% and 94% for proanthocyanidins treatment group of 0.1% in the 14 th day. Moreover,with the increasing of additive amount of proanthocyanidins from Chinese bayberry leaves,the induction period of lard oil was increasing. When the additive amount was 0.1%,the induction period and oxidation protection factor were between that of BHT and TBHQ and there were no significant difference with BHT(p>0.05),showing that proanthocyanidins from Chinese bayberry leaves had antioxidant activity in lard oil.