title: Sodium dithionite-enhanced quality of radix scutellariae through modification of secondary metabolism.
abstract: BACKGROUND
  The quality of radix scutellariae is particularly associated with environmental stresses, but detailed mechanisms remained unclear. Plant under unfavorable situation generates redundant reactive oxygen species (ROS), and ROS can modify the secondary metabolism. The varied quality of radix scutellariae could be explained by ROS.
  
  
  METHODS
  .004, 0.4, and 40 μmol/L of sodium dithionite (Na2S2O4), a material producing ROS, were applied toScutellaria baicalensisto mimic unfavorable situation. The relationship between ROS, antioxidant enzymes activity, and secondary metabolite was investigated.
  
  
  RESULTS
  ROS level fails to rise due to both the antioxidase and the secondary metabolites. The activities of both superoxide dismutase and catalase in the roots ofS. baicalensisshowed a moderately improvement, meanwhile the phenylalanine ammonia lyase was strongly expressed, and the biosynthesis of flavonoids was heavily elevated. Although the glycosides such as baicalin and wogonoside changed little, the aglycones with the highest effective, such as baicalein and wogonin, were increased by approximately 50%-100%.
  
  
  CONCLUSIONS
  This is very valuable in insight into the stress physiology and provides a strong tool to enhance the quality of radix scutellariae.
authors.affiliation: Department of Pharmacognosy, Heilongjiang University of Chinese Medicine, Harbin 150040, China.
authors.forename: Guo
authors.initials: G
authors.lastname: Huimin
authors.affiliation: Department of Pharmacognosy, Heilongjiang University of Chinese Medicine, Harbin 150040, China.
authors.forename: Fu
authors.initials: F
authors.lastname: Xiaoying
authors.affiliation: Department of Pharmacognosy, Heilongjiang University of Chinese Medicine, Harbin 150040, China.
authors.forename: Du
authors.initials: D
authors.lastname: Hongwei
authors.affiliation: Department of Pharmacognosy, Heilongjiang University of Chinese Medicine, Harbin 150040, China.
authors.forename: Cong
authors.initials: C
authors.lastname: Wei
authors.affiliation: Department of Pharmacognosy, Heilongjiang University of Chinese Medicine, Harbin 150040, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Xiangcai
keywords: Antioxidase; Scutellaria baicalensis; flavonoids; reactive oxygen species; secondary metabolite