High-yield oleaginous fungi and high-value microbial lipid resources from Mucoromycota

Mucoromycota are diverse in microbial oils, but oil-related studies have long been confined to a few particular genera and species. This study used the Sherlock Microbial Identification System to determine fatty acid compositions and consequently discover potential resources from 669 strains representing 133 species in 28 genera in 11 families from the core mucoromycotan orders Mortierellales , Mucorales , and Umbelopsidales . Results showed that 34% of strains, 50% of species, and 46% of genera were oleaginous. Eleven genera were proposed as oleaginous taxa for the first time. Among them, Backusella was highlighted in accumulating as high as 59.08 ± 2.24% of oils. Twenty-five and 50 strains were screened as potential high-yield fungi for oils and high-value fatty acids respectively. Pilaira produced the most C18:2, while Rhizopus and Thamnostylum produced the most C18:3. Only strains of Mortierella produced C20:4; Mo. amoeboidea CGMCC 3.15949 yielded 58.00% ± 1.15% of C20:4, which suggests it is an excellent source of C20:4. This study suggests for the first time that the bulk of Mucoromycota is rich in lipids. More genera and species were discovered herein as oil-producing resources. These findings serve as a foundation for further research on microbial oil production.