18-09: Production of Biosurfactant By Bacillus sp. Isolated From Sirri Island Petroleum Contaminated Soils

Introduction: Biosurfactants are surface active agents with broad range commercial applications in various industries and have considerable advantages over their chemical counterparts. The aim of this research is isolation of biosurfactant producing bacteria and analysis of optimize environmental conditions like temperature and pH, and molecular identification of Selected bacteria species.

Materials and Method: Samples of this research were collected from 8 selected points of oil contaminated soils in Sirri Island-IRAN. Primary screening tests including Hemolytic activity, Drop collapse technique, Oil Spreading method were preformed and species with the most positive results were leaded to complementary screening tests like emulsification activity, foaming and surface tension measurement.

Results: Totally 160 bacteria species were isolated. During primary and complementary screening tests, 59 species showed hemolytic activity, 46 had drop collapsing ability and 18 species showed positive results in emulsification, foaming and surface tension reduction. Finally, two Bacillus species ( S₅,No6 and S₇,No7) found to be able to reduce surface tension more than 30 mN/m.

Conclusion: Two strains with a high amount of biosurfactant production and emulsification ability were resulted from the present study. According to the high potential of Bacillus sp. especially for Microbial Enhanced Oil Recovery (MEOR) and Bioremediation of oil contamination we can hope that further study of the isolates characteristics and looking for new local strains can play an important role in their application in oil industry.