تجزیه ی زیستی نفتالین در خاک های آلوده به نفت خام توسط کنسرسیوم باسیلوس‌ها

Background and Aim: The petroleum contamination is one of the inevitable consequences of population increase and energy consumption. In this study, the method of Bioremediation and Bacillus bacteria have been used in order to remove the petroleum contamination. Material and Methods: The samples of soil were collected and the bacteria were isolated and identified.Then, the production of Biosurfactant, the rate of naphthalene degradation and appropriate growth conditions of them were examined. Results: The Bacillus sp. included Bacillus cereus, Paenibacillus lactis, Bacillus fusiformis and Bacillus subtilis. The pure cultures and consortium have surface tension values less than 40 mN/m. Therefore, they were considered biosurfactant producers. The consortium had the tolerance ability of naphthalene up to 1000ppm.The appropriate conditions for the growth of Bacillus consortium was pH equal to 6, shaker rate 150 rpm, nitrogen source of Yeast extract and the concentration of naphthalene equal to 200ppm. Conclusion: Bacillus consortium had more ability compared to single strains for reducing the surface tension, production of Biosurfactant, growth in culture media containing naphthalene and its degradation. It has indicated in several of the similar researches that Bacillus consortium or other bacteria have more ability in Biodegradation of organic contaminants.