title: H2O2 Improves Quality of Radix scutellariae Through Anti-oxidant Effect.
abstract: BACKGROUND
  The correlation between the quality and geographical origin of herbal medicine was traced back to Tang Dynasty in China, more than 1200 years, and the effects of ecological environments on the secondary metabolites such as flavonoids have been confirmed. However, little is known about how the adversity impacts on the quality. Reactive oxygen species (ROS) may be medium between the ecological environment and the secondary metabolism.
  
  
  METHODS
  The fresh roots of Scutellaria baicalensis Georgi were treated with 0.002 μmol/L, 0.2 μmol/L, and 20 μmol/L H2O2, respectively. A stress model was established to elucidate the change of secondary metabolism, anti-oxidant enzyme system, and enzymes relating to flavonoids.
  
  
  RESULTS
  The activities of superoxide dismutase, catalase and peroxidase decreased. Too much H2O2, firstly, boosted transformation of flavonoids glycoside into aglucon with the most remarkable activities through UDP-glucuronate baicalein 7-O-glucuronosyltransferase (UBGAT), and β-glucuronidase (GUS), then regulated the gene expression of phenylalanine ammonialyase, GUS, and UBGAT, and increased the contents of flavones, motivated the flavonoid glycoside converting into aglucon. With this action, the flavones displaced the anti-oxidant enzymes. The higher the dosage, the more baicalein and wogonin increased, the later they took action.
  
  
  CONCLUSIONS
  The plant secondary metabolites to keep ROS constant are identical to the effective materials in clinic. They are closely linked. H2O2 can improve flavones, especially the aglucon, and further increased the quality of herbal medicine, which possesses very important value in medical practice.
  
  
  CONCLUSIONS
  H2O2 decreasing the activities of CAT and POD lead to accumulation of more H2O2. Excess of H2O2 up-regulated PAL, BUG, promote biosynthesis of flavones, and enhance the nonenzyme system. "↑" and "↓" represent activity or content "up" and "down" respectively.
authors.affiliation: Department of Pharmacognosy, College of Pharmacy, Heilongjiang University of Chinese Medicine, Harbin 150040, China.
authors.forename: Song
authors.initials: S
authors.lastname: Qi
authors.affiliation: Department of Pharmacognosy, College of Pharmacy, Heilongjiang University of Chinese Medicine, Harbin 150040, China.
authors.forename: Cao
authors.initials: C
authors.lastname: Wu-Lin
authors.affiliation: Department of Pharmacognosy, College of Pharmacy, Heilongjiang University of Chinese Medicine, Harbin 150040, China; Department of Pharmacognosy, College of Pharmacy, Heilongjiang University of Chinese Medicine, Harbin 150040, China.
authors.forename: Jiang
authors.initials: J
authors.lastname: Hua
authors.affiliation: Department of Pharmacognosy, College of Pharmacy, Heilongjiang University of Chinese Medicine, Harbin 150040, China.
authors.forename: Zhang
authors.initials: Z
authors.lastname: Ai-Hua
authors.affiliation: Department of Pharmacognosy, College of Pharmacy, Heilongjiang University of Chinese Medicine, Harbin 150040, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Xiang-Cai
keywords: Anti-oxidase; H2O2; Scutellaria baicalensis; flavonoid; secondary metabolism