Effect of H2O2 on Secondary Metabolism in Atractylodes chinensis and Its Mechanism / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo investigate the effect of exogenous H2O2 on secondary metabolism in Atractylodes chinensis and its mechanism. MethodFresh rhizomes of A. chinensis were treated with 5.0， 1.0， 0.2， 0.04 mmol·L-1 H2O2 solution and clean water， and the relationships between the contents of reactive oxygen species， activities of antioxidant enzymes， activities of key enzymes of secondary metabolites， and contents of secondary metabolites in A. chinensis were compared. ResultUnder treatment with exogenous H2O2， the content of reactive oxygen species and malondialdehyde （MDA） in the fresh rhizomes of A. chinensis were significantly elevated on the 4th day， and returned to normal level on the 6th-8th day. The activities of superoxide dismutase （SOD）， catalase （CAT） and peroxidase （POD） were all increased first and then decreased， and reached the peak on the 4th， 4th-6th and 2th-4th day， respectively. The activities of 3-hydroxy-3-methyl glutaryl coenzyme A reductase （HMGR） and acetyl CoA carboxylase （ACC）， key enzymes of the secondary metabolites， were remarkably enhanced， and under treatments with different concentrations of H2O2， the activities of key synthetic enzymes of the secondary metabolites in 0.2 mmol·L-1 H2O2 group were increased most， with the highest biosynthesis of secondary metabolites. The contents of atractylodin， β-eudesmol， atractylone， atractylenolide Ⅱ， and atractylenolide Ⅲ on the 6th day of 0.2 mmol·L-1 H2O2 treatment were 89.5%， 108.7%， 308.8%， 64.7% and 9.3%， respectively higher than those in the control. ConclusionThe antioxidant enzymes and secondary metabolites in A. chinensis synergistically maintain the balance of reactive oxygen species， and exogenous H2O2 can improve the medicinal quality of A. chinensis remarkably.