12C6+离子辐射下海迪茨氏菌及其表面活性物质研究

 生物表面活性剂具备无毒、生物降解等优点，这些特性尤其适合于石油的生物降黏、提高原油采收率、重油污染土壤的生物修复等。本文以一株在唯一碳源培养基中能产生胞外生物表面活性剂的海地茨开菌(Dietzia maris)为对象，利用不同剂量¹²C⁶⁺离子束辐射该菌，从大量突变株中筛选出一株正突变菌株YR9。研究表明，经25Gy剂量辐照至该菌突变率最佳，生物表面活性剂产量达到6336.45U/mL，比未经诱变处理菌株提高了2.25倍，能够完全降解n-C₅、n-C₆、n-C₁₆、甲苯、喹啉、咔唑、邻二甲苯、对二甲苯、汽油、萘、邻苯二酚，但对n-C₅、萘降解力降低。分析了该菌产生物表面活性剂的理化性质，对其产物进行了鉴定，对产生生物表面活性剂的条件进行了优化研究。

Dietzia maris Induced by Carbon-ion Beams and Its Biodegradation Ability

Biosurfactants have the advantages of non-toxic, biodegradable, and these properties are particularly suitable for the biological viscosity reduction of oil, oil recovery enhancement, and the bioremediation of heavy oil polluted soil. By using Dietzia maris bacteria that are the only one could produce extracellular biosurfactants in the sole carbon source medium radiated by the different doses of ¹²C⁶⁺ ion beam, a positive mutant strain YR9 is screened from the large number of mutants. The studies show that the best mutation rate of the bacteria is obtained with the 25Gy dose irradiation, resulting in surface active dose of 6336.45U/mL. Comparing with the strain without mutagenic treatment, the improvement of 2.65-fold is achieved; it almost able to completely degrade n-C₅, n-C₆, n-C₁₆, toluene, quinoline, carbazole, o-xylene, p-xylene, gasoline, naphthalene, catechol, however for n-C₅, naphthalene degradation is lower. The physical and chemical properties of the surface active agent produced by the bacteria are analyzed, its products are identified, and the condition produced surface active agent is optimized.