Highlighting the marine fungi Cunninghamella echinulata-9A5 as bioemulsifier for treating tannery leather residue.

This study has investigated the biosurfactant and bioemulsifier potential of the fungal malt broth 9A5M, obtained from the marine fungus Cunninghamella echinulata-9A5. The E24 emulsification index of 9A5M were evaluated by using vegetable oils, burnt motor engine oil and residues from leather treatment. The chemical profile 9A5M was delineated by GC-MS, and its stability was determined by zeta potential and hydrodynamic diameter (D), obtained by Dynamic Light Scattering analysis. Lipase dosage, total protein content, and toxicity in alternative models were also determined. 9A5M gave the best E24 emulsification index values (%) for burnt motor engine oil and leather industrial waste: 78.10 ± 0.05 and 77.10 ± 0.00, respectively, and displayed stable anionic profile when temperature and pH were varied. GC-MS confirmed that the ethyl acetate extract of 9A5M contained fatty acids, pyranone, alkanes, and dipeptides as major compounds. 9A5M had total protein content of 0.453 mg and specific lipase activity of 0.441 U/mg of protein. In addition, 9A5M was not toxic against the alternative models Galleria mellonela or Caenorhabditis elegans. The results reported here contribute to knowledge about the biosurfactant and bioemulsifier properties of 9A5M marine sample.