Valorization of Dairy Wastewater into microbial lipid by an oleaginous yeast Pseudozymasp. for Sustainable Biodiesel Production

This study evaluated the potential accumulation of lipid of isolated Yeast from soil sample by using Synthetic dairy wastewater as a renewable feedstock for biodiesel production. on the basis of their lipid accumulation five oleaginous Yeast (i.e.Y1, Y2, Y5, Y6, Y7) were screened (lipid content >20%) and the productivity on a Yeast Peptone medium. The effect on capacity of lipid accumulation by different carbon sources (i.e. Galactose, Glucose, Starch, Sucrose and Cellulose) of the Yeast isolates was evaluated. The Y1 oleaginous yeast which shows closet relation to Pseudozyma genus could accumulate (54%) lipid, biomass production (2.47g/l) using Glucose and galactose as a source of carbon. Furthermore, the Y1 yeast strains demonstrated effective utilization of dairy wastewater, resulting in a substantial reduction (~50%) in Chemical Oxygen Demand (COD), along with notable lipid accumulation (49.8%) and biomass production (1.5 g/l). The lipids produced by Yeast Y1 had the presence of various fatty acid i.e. oleic acid, alpha linolenic acid etc., and presence of high percent of saturated fatty acid over total fatty acid as visually confirmed by Nile red staining and chemical characterized by nuclear magnetic resonance (NMR) spectroscopy. NMR analysis indicated that the lipids extracted from Yeast Y1 were suitable for biodiesel applications. Overall, the findings of this study underscore the potential of leveraging dairy wastewater as a cost-effective and efficient resource for biodiesel production using oleaginous yeast. This approach not only addresses contemporary concerns regarding fuel shortages, food security and climate change but also contributes to the sustainable management of wastewater resources.