Amelioration of lipid production by Cunninghamella echinulata: statistical optimization and GC-MS characterization

Lipids have garnered attention for their importance in pharmaceuticals and nutraceuticals. Famously, oleaginous filamentous fungi produce essential fatty acids. In this study, optimization using one factor at time (OFAT) and response surface methodology-Box-Behnken design (RSM-BBD) approaches, Cunninghamella echinulata showed the highest lipid content (61.23%) under optimized OFAT conditions (60 g/L, glucose; 2 g/L; ammonium tartrate; pH value, 7 at 30 °C, and shaking for seven days). Lipid content of 59.37% was achieved using the BBD. One-way ANOVA indicated temperature significantly affected lipid content, while two-way ANOVA revealed significant interactions between temperature and ammonium tartrate concentration, pH and incubation time, and inoculum size and glucose concentration. Various agro-wastes used as media for C. echinulata growth and production of lipid with peach yielding the best lipid content (49.30%). Comparative analysis of lipid extracts by GC-MS of the best yield conditions revealed nineteen different fatty acids, with oleic acid, linoleic acid, gamma-linolenic acid, and palmitic acid present in high percentages of 35.49%, 21.31%, 21.78%, and 13.44%, respectively. The extracted lipids demonstrated antibacterial potential towards Staphylococcus aureus , Escherichia coli , and Bacillus subtilis , as well as antifungal efficacy against Candida albicans and C. glabrata . The inhibition zones ranged from 9 to 19 mm with 50 µL of 10% extracts (100 mg/mL). This investigation revealed that optimization of C. echinulata represents promising candidate for high lipid yield in addition to lipid extracts may serve as potential antimicrobial agents in the pharmaceutical industry.