Evaluation of oleaginous yeasts isolated from lignocellulosic waste, sugarcane bagasse as a potential source for single cell oil production and other biochemical metabolites.

Abstract

Purpose The microorganisms that possess diverse and improved traits for biotechnological applications provide an opportunity to address some of the current industrial challenges such as sustainability of fuel energy and food. The aim of this study was to evaluate the potential of yeast isolates from sugarcane bagasse for single oil production. Methods Oleaginocity of the yeasts was confirmed through gravimetric analysis of lipids, Nile red, sulfo-phosphovanillin (SPV) and gas chromatography method for fatty acid methyl esters (FAME). Identification of the selected yeasts was carried out through 5.8S of the ribosomal internal transcribed spacer, ITS and 26S ribosomal DNA (rDNA) sequences. Results The yeast isolates accumulated lipids between 28% and 67% of the dry cell weight, and 22%-33% based on SPV assay, qualifying them as oleaginous yeasts. the isolated yeasts were identified as Candida ethanolica and Pichia manshuriica. Conclusion The lipids contained high level of fatty acids in the following order: oleic acid, palmitic acid, stearic acid and linoleic acid, which made up 82% of the total lipids. The fatty acids composition of the selected yeast species was found to be suitable for the applications in biofuel, nutraceutical and food industry.