Assessment of myco-diesel and a comparison of their quality indicators with global standards

The quality standards of good biodiesel are directly proportional to its compatibility with internal combustion engines without the need for additional modifications. This study aimed to investigate the acceptability of biodiesel derived from fungi based on biodiesel quality characteristics according to international standards. Twelve published fungal isolates, identified as oleaginous fungi, were targeted, and their suitability for use in internal combustion engines was predicted and compared to these standards. The results showed that, despite relative variation in fatty acid methyl esters among the fungal isolates, the biodiesel derived from fungi achieved a cetane number ranging from 53 to 68 for most isolates. The kinematic viscosity showed acceptable results for 10 isolates according to American Society for Testing & Materials (ASTM)/European Norm (EN) International Organization for Standardization (ISO) standards, while the ANER/AFUS isolates showed unacceptable values according to these standards. The density value for most fungal isolates showed compliance with ASTM/EN ISO standards. The diesel fuel derived from fungi exhibited very acceptable values for cloud point and Cold filter plugging point. Due to the high concentration of unsaturated fatty acids, the diesel fuel derived from fungi may be susceptible to oxidation, which could affect its oxidative stability and shelf life. Furthermore, the diesel fuel derived from fungi showed a higher heating value exceeding 20 in most isolated samples. The saponification values for most isolated samples ranged between 100 and 200 mg KOH/g of lipids. Based on the European standard, the iodine value of the diesel fuel derived from fungi did not exceed 120 g of iodine I₂/100 g.