Approaches to improve the lipid synthesis of oleaginous yeast Yarrowia lipolytica: A review

Microbial oils have become a research hotspot in alleviating energy challenges and environmental problems because of their potential to be green alternatives of traditional fossil fuels. Yarrowia lipolytica is a promising oleaginous yeast that can utilize various, especially low-cost carbon sources to synthesize considerable lipids more than 30% of dry cell weight, which is attracting researchers' attention. Based on well understanding of its lipid synthesis and metabolism mechanism, various optimization approaches have been studied dispersedly to improve the lipid synthesis and realize the industrial-scale application of Y. lipolytica. Some approaches are focused on improving and optimizing culture conditions, such as temperature, pH value, and rotating speed, etc. Other approaches are dedicated to the optimization of nutrient elements, such as carbon source, nitrogen source type and/or concentration, and C/N ratio, etc. Some adjust the cultivation mode to facilitate nutrient assimi-lation and transformation, and others use genetic engineering to modify this yeast. This review focuses on the comprehensive and detailed analyses of feasible enhancement approaches for lipid synthesis. Some prospects will also be introduced as references for further study.