Lipid production by Cryptococcus albidus using biowastes hydrolysed by indigenous microbes
The efficiency of Cryptococcusalbidus was evaluated for its abilities to assimilate onion and apple hydrolysates as a medium for lipid production. Onion waste (OW) and apple waste (AW) were hydrolysed at an organic load of 2% total solids by indigenous microbes under mesophilic conditions. The indigenous microbes effectively hydrolysed both wastes giving the highest reducing sugar content of 4.8 g/L and 10.8 g/L with OW and AW hydrolysates, respectively. The microbiome analysis revealed that most of the indigenous microbes belonged to genus Bacillus and a significant population of α-proteobacteria and γ-proteobacteria were also present. Cell retention culture of C. albidus at a dilution rate of 0.01 h−1 resulted in a total dry cell weight (DCW) of 13.5 g/L with an intracellular lipid content of 20.0% at 168 h, corresponding to an enhancement of 3.48-folds and 2.37-folds in DCW and lipid concentration, respectively, as compared to batch fermentation.
KeywordsBiodiesel Cryptococcus albidus Lignocellulose Oleaginous yeast Microbiome analysis Waste hydrolysis
This research was supported by the National Research Foundation of Korea (NRF-2017R1A2B4002371). ES and PK are thankful for the financial support provided by a Brain Korea 21 plus project.