Insight into the Regulatory Mechanism of Carbon and Nitrogen Nutrition on Cell Multiplication and Microbial Lipid Synthesis in Yarrowia Lipolytica

Abstract

Volatile fatty acids (VFAs) derived from organic waste offer promising and cost-effective carbon sources for the production of microbial lipids. This study demonstrates the significant influence of nitrogen nutrition on cell proliferation and microbial lipid synthesis in Yarrowia lipolytica during high-content acid cultivation. Further investigations into nitrogen sources revealed that NH4Cl and urea are suitable options for cultivating Y. lipolytica to produce microbial lipids, resulting in yields ranging from 2.00 to 2.50 g/L. Moreover, pH fluctuations were found to be influenced by both the nitrogen source and acid utilization, with pH adaptation helping alleviate acid inhibition caused by high-content VFAs. Under optimized cultivation conditions, the highest yield of microbial lipids reached 4.00 g/L, accompanied by a dry cell weight of 9.91 g/L and a microbial lipid content of 40.37%, consisting predominantly of C16~18 fatty acids.

Keywords: Microbial lipid, Volatile fatty acids, Nitrogen source, Carbon source, Organic wastes, Yarrowia lipolytica