Introduction of halotolerant Mucor circinelloides UTMC 5032 for bioremediation crude oil hydrocarbons

Abstract

Introduction: Biodegradation of hydrocarbons in the saline environment is diminished due to the reduced solubility of hydrocarbons and oxygen and lower microbial diversity because of inhibitory effect of salt. Materials and methods: In this research, fungi isolation was carried out from salty oil contaminated soil from different parts of Iran. Then, the ability of crude oil degradation was measured for each isolate in the presence of 50 g/l NaCl by total petroleum hydrocarbon (TPH) assay. The salt tolerance and crude oil degradation capacity of the selected isolate was evaluated in medium containing different salt concentration by analysis of TPH, FTIR and dried cell weight assay. Finally, the selected isolate was studied for biosurfactant production and identified using morphological and molecular approach. Results: In this study, 15 different halotolerant fungal species were isolated. TPH assay in medium containing crude oil (1%) and salt (50 g/l) showed that the isolate S-05 with 60 % oil removal was the best strain. FTIR analysis revealed that 90% of aliphatic compounds were removed when treated with S-05. Biosurfactant production assay indicated that this strain can produce surface active compounds in presence and absence of salt. Molecular identification confirmed that the S-05 belongs to Mucor circinelloides with 100% similarity. Discussion and conclusion: Our results indicate that M. circinelloides UTMC 5032 is potent fungus for bioremediation in saline oil contaminated soils.

Keywords

• Bioremediation
• Saline soils
• Halotolerant fungi
• Mucor circinelloides UTMC 5032