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Title: Biomanufacturing of value‐added products from oils or fats: A case study on cellular and fermentation engineering of Yarrowia lipolytica
Abstract

The United States produces more than 10 million tons of waste oils and fats each year. This paper aims to establish a new biomanufacturing platform that converts waste oils or fats into a series of value‐added products. Our research employs the oleaginous yeastYarrowia lipolyticaas a case study for citric acid (CA) production from waste oils. First, we conducted the computational fluid dynamics (CFD) simulation of the bioreactor system and identified that the extracellular mixing and mass transfer is the first limiting factor of an oil fermentation process due to the insolubility of oil in water. Based on the CFD simulation results, the bioreactor design and operating conditions were optimized and successfully enhanced oil uptake and bioconversion in fed‐batch fermentation experiments. After that, we investigated the impacts of cell morphology on oil uptake, intracellular lipid accumulation, and CA formation by overexpressing and deleting theMHY1gene in the wild typeY. lipolyticaATCC20362. Fairly good linear correlations (R2 > 0.82) were achieved between cell morphology and productivities of biomass, lipid, and CA. Finally, fermentation kinetics with both glucose and oil substrates were compared and the oil fermentation process was carefully evaluated. Our study suggests that waste oils or fats can be economical feedstocks for biomanufacturing of many high‐value products.

 
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Award ID(s):
1911480
NSF-PAR ID:
10235913
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Biotechnology and Bioengineering
Volume:
118
Issue:
4
ISSN:
0006-3592
Page Range / eLocation ID:
p. 1658-1673
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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