Banana peel waste management for single-cell oil production

Banana peel waste was explored as a substrate for single-cell oil production using a promising oleaginous yeast Rhodotorula glutinis NRRL Y-1091 and fungus Ganoderma wiiroense under solid-state versus submerged fermentation for 8 days. Higher productivity and yield of lipids of 0.020 g lipid/g starch was recorded in both types of fermentation, with the fungal isolate G. wiiroense as compared to R. glutinis. Amylase, β glucosidase and inulinase activity were also monitored, which followed a similar trend, with highest values on 6th or 8th day of incubation. Lipase activity was not detected in the crude extract of both strains. Inulinase activity was highest at 8th day incubation in submerged fermentation with the fungal isolate G. wiiroense. FAME analyses revealed that the composition of the lipids had promising potential as good-quality biodiesel. The high levels of inulinase activity in the yeast and fungal strains enhanced the production of monomeric sugars from inulin present in banana peel, which, in turn, facilitated greater conversion to lipids and stimulated bio-oil production.