title: Dissolved oxygen control strategy for improvement of TL1-1 production in submerged fermentation byDaldinia eschscholzii.
abstract: BACKGROUND
  2,3-Dihydro-5-hydroxy-2-methylchromen-4-one (TL1-1) is a phenolic compound with significant anti-fungal and anti-cancer activities produced byDaldinia eschscholzii(D. eschscholzii). However, studies have rarely been reported on the fermentation process ofD. eschscholziidue to the urgent demand for its pharmaceutical researches and applications.
  
  
  RESULTS
  In this work, the optimal fermentation medium for improved TL1-1 yield was first obtained in a shake flask. As the fermentation process was scaling up, the marked effects of dissolved oxygen (DO) on cell growth and TL1-1 biosynthesis were observed and confirmed. Controlling a suitable DO level by the adjustment of agitation speed and aeration rate remarkably enhanced TL1-1 production in a lab-scale bioreactor. Moreover, the fermentation ofD. eschscholziiwas successfully applied in 500-L bioreactor, and TL1-1 production has achieved 873.63 mg/L, approximately 15.4-fold than its initial production (53.27 mg/L).
  
  
  CONCLUSIONS
  Dissolved oxygen control strategy for enhancing TL1-1 production was first proposed. Furthermore, control of the appropriate DO level has successfully performed for improving TL1-1 yield and scale-up ofD. eschscholziifermentation process.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Box 283#, Shanghai, 200237 People's Republic of China ; Shanghai Collaborative Innovation Center for Biomanufacturing Technology, 130 Meilong Road, Shanghai, 200237 People's Republic of China.
authors.forename: Xing-Chen
authors.initials: XC
authors.lastname: Wei
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Box 283#, Shanghai, 200237 People's Republic of China ; Shanghai Collaborative Innovation Center for Biomanufacturing Technology, 130 Meilong Road, Shanghai, 200237 People's Republic of China.
authors.forename: Liu
authors.initials: L
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Box 283#, Shanghai, 200237 People's Republic of China ; Shanghai Collaborative Innovation Center for Biomanufacturing Technology, 130 Meilong Road, Shanghai, 200237 People's Republic of China.
authors.forename: Yan-Hua
authors.initials: YH
authors.lastname: Lu
keywords: Daldinia eschscholzii; Dissolved oxygen control; Submerged fermentation; TL1-1