title: [Effects of Oxygen Carriers on Submerged Fermentation of Poria cocos].
abstract: OBJECTIVE
  To explore the regulation effects of oxygen carriers on Poria cocos submerged fermentation system which usually can be seriously inhibited by dissolved oxygen limitation.
  
  
  METHODS
  One-factor-at-a-time design was employed to determine the oxygen carrier addition strategy through analyzing the effects of different oxygen carries, concentration and adding time of oxygen carrier on Poria cocos submerged fermentation. Then the oxygen carrier addition strategy was established and the metabolic processes of Poria cocos submerged fermentation were investigated comprehensively.
  
  
  RESULTS
  The optimal oxygen carrier addition strategy was adding 1% (V/V) Tween-80 at 48 h after inoculation. Under this optimized condition, dry cell weight of Poria cocos reached 13.43 g/L in a 10 L bioreactor, while yields of exopolysaccharides and pachymic acid were 8.58 g/L and 989.52 μg/L, respectively, which exhibited obvious promoting effects compared with no addition oxygen carrier fermentation process.
  
  
  CONCLUSIONS
  Tween-80 can remarkably increase the levels of cell growth, exopolysaccharides biosynthesis and pachymic acid in Poria cocos submerged fermentation system, which may provide new reference for further exploring dissolved oxygen limitation in high density fermentation of medical fungi efficiently.
authors.forename: Pei-wu
authors.initials: PW
authors.lastname: Cui
authors.forename: Ya-Qiang
authors.initials: YQ
authors.lastname: Hu
authors.forename: Yu-ping
authors.initials: YP
authors.lastname: Zhong
authors.forename: Hui
authors.initials: H
authors.lastname: Zhu
authors.forename: Yu-lan
authors.initials: YL
authors.lastname: Yin
authors.forename: Zhao-yang
authors.initials: ZY
authors.lastname: Tan
mesh_terms: D019149:Bioreactors; D005285:Fermentation; D062610:Fungal Polysaccharides / Q000378:metabolism*; D010100:Oxygen / Q000737:chemistry*; D055441:Poria / Q000378:metabolism*; D014315:Triterpenes / Q000378:metabolism*
chemical_list: D062610:Fungal Polysaccharides; D014315:Triterpenes; D010100:Oxygen; C102487:pachymic acid