Studies On Screening And Determination Of Microbial Organic-sulfur-degradating, Optimization Conditions Of Microbail Strain Desulfurization And Its Mechanism On Organic-sulfur Biotransformation

With the development of modern biotechnology, more and more microorganism is being used in environment disposal. In this paper, the screening and determinant of microbial desulfurization, and the characteristic of strain, the biotransformation conditions of desulfurization, mechanism of Staphyloccus sp. Strain SB113were studied systematically.The main and complex organic-sulfur in fossil fuel is thiophene-group. Use thiophene as mode compound and unique sulfur source, compare change of organoc-sulfur content in medium, microbe has the capacity of desulfurization was selected. After managed with ultraviolet radiation and DES,the highest desulfurization efficiency strain SB113 was gained.Isolation and purification the strain SB113, and through detection of its appearance, physiological and biochemical characteristics, growth characteristics, it was identified Staphyloccu Genus according to Bacteriological Analytical Manual (FDA) and Taxology of Microorganism, and named it Staphyloccus sp. Strain SB113.In order to gain a high desulfurization efficiency of Staphyloccus sp. Strain SB 113. Components of germ medium and conditions of seed culture were studied by Single Factor design. And optimized sulfur-degradation conditions by combination Single Factor design and orthogonal test design.The result showed that optimum composition of the germ medium is Glucose 1.0%, Peptone 1.0%, NH4C11.0%, Thiophene 2.0%, CaCl2 0.001%, ZnCl2 0.005%, MgCl2 0.1%, KH2PO4 0.1% , pH 6.8. And at a rotate speed of 160-180rpm, 36-37癈 of temperature, a period of 16h seed cuture, Staphyloccus sp. Strain SB113 will has more efficiency in desulfurization.Under a germ culture condition like thus, the optimum fbiotransformation conditions as following : inoculation capacity of 8.0%, pH 6.5-6.7, and shaking rotate speed at 180-220rpm, a temperature of 32癈, treated with Staphyloccus sp. Strain SB113 for 32h. The efficiency of Staphyloccus sp. Strain SB 113 desulfurization in diesel oil reach 33.7%Result of orthogonal test showed that among the five biotransformation factors: time, initial pH, inoculation capacity, temperature and shaking rotate speed has little effect on Staphyloccus sp. Strain SB113 desul-efficiency.Result of Staphyloccus sp. Strain SB113 desulfurization mechanism study showed that this bacteria its own enzyme system transform organic-sulfur in diesel oil into diesel oil organic-sulfur by its own biotransformation enzyme system., which was expelled from fuel with water and sequentially reach the aim of removing sulfur.