Waste Sunflower Oil as a Feedstock for Efficient Single-Cell Oil and Biomass Production by Yarrowia lipolytica

TL;DR

This study shows that waste sunflower oil can be efficiently converted into single-cell oil and biomass using the yeast Yarrowia lipolytica, offering a sustainable and cost-effective bioprocess.

Contribution

The paper introduces an optimized multi-response approach for SCO production using waste sunflower oil and Yarrowia lipolytica under various experimental conditions.

Findings

The highest lipid content (72.86% of dry cell weight) was achieved using 80 g/L waste sunflower oil and 2% Tween 80 in a sterilized, sonicated medium without nitrogen.

Maximum biomass production (4.18 g/L) was obtained with high nitrogen and WCO concentrations in the absence of Tween 80 and sonication.

Nitrogen concentration and Tween 80 significantly influenced palmitic acid content in the produced oil.

Abstract

In this study, single-cell oil (SCO) production from waste sunflower oil was optimized using Yarrowia lipolytica IFP29 (ATCC 20460). Optimizations were performed via a multi-response approach based on the Taguchi orthogonal array design (L16), targeting maximum biomass concentration and lipid content (based on dry cell weight). A total of 16 experimental conditions were tested with five key parameters: nitrogen concentration (0, 1, 2, and 4 g/L), WCO concentration (20, 40, 60, and 80 g/L), Tween 80 content (0, 0.5, 1, and 2%) as well as the application of sonication and sterilization. Analysis of variance revealed that all tested factors, except Tween 80 and sonication, had statistically significant effects on lipid content (p < 0.05). The highest lipid content (72.86% of dry cell weight) was obtained in a sterilized, sonicated medium containing 80 g/L WCO and 2% Tween 80, under conditions without nitrogen supplementation. In contrast, maximum biomass production (4.18 g/L) was achieved in sterile cultures with high nitrogen (4%) and high WCO (80 g/L) in the absence of Tween 80 and sonication. Palmitic acid (C16:0) content was also successfully optimized, with nitrogen concentration and Tween 80 supplementation exerting a statistically significant effect (p < 0.05). These results highlight the potential of waste sunflower oil as a low-cost feedstock for SCO production and support the development of economically and environmentally sustainable bioprocesses.

Figures