Circular Production of Microbial Lipids: Integrated Recycling of Yarrowia lipolytica NRRL Y-1095 Residual Biomass as Substrate
摘要
This study addresses some of the existing challenges in producing biofuels from microbial oils. The recovery step of these intracellular lipids results in a deoiled biomass, characterized as a residue from the production chain of third-generation biodiesel. This study explored the hydrothermal chemical hydrolysis of residual biomass from the yeast lipid extraction, by exploring it as an alternative nutrient source in oleaginous yeast cultivation. The cultivated Yarrowia lipolytica biomass was deoiled and treated by hydrothermal acid (0.5 M H2SO4) and basic (0.75 M NaOH) hydrolysis, at 121 °C, 1.1 atm for 1.5 h. The hydrolysates were characterized as reducing sugars and used for new Y. lipolytica cultivation, with or without glucose supplementation, to produce oleaginous biomass. The hydrolyzed stream from Y. lipolytica hydrothermal processing showed to be promised for reuse as a growth substrate. The addition of this stream as a substrate promoted 1.3 times higher biomass production and twice the lipid content, compared to the medium with glucose alone, resulting in 16.9 g L⁻¹ and 17.13% (m m− 1), respectively. This simple recycling strategy lowers costs and environmental impacts in microbial biofuel production by providing affordable carbon sources and nutrients for yeast cultivation. It makes the process attractive to biorefineries and biofuel producers while promoting advancements in microbial lipid technology.
Graphical abstract