摘要
分离出能高效降解机油的真菌并研究其使用方法。从机械润滑油污染的土中分离出2株真菌，GXUA和GXUB。形态鉴定为曲霉属（Aspergillus）菌。rDNA的ITS序列同源性分析表明，GXUA与A．tubingens，GXUB与A．fumigatus菌株SRRC43完全同源。根据均匀设计的油-矿质液中的摇床发酵结果，混合菌体对机油的降解效率高于单菌株，最佳发酵条件为25g菌丝体／L矿质液，DH：5．0，26℃。在此条件下，于10g机油／L矿质液中摇床发酵9d，其降解效率为95．90％。液-质色谱分析表明，混合菌能降解机油中700-900Dt的大分子。用两菌株的孢子和其他两种生物材料试制了实验室级的颗粒（直径1cm）生物制剂。在实验室级水平上，按500粒／m^2水面和150粒／kg土用量分别处理具有约2mm厚油膜的水（自来水和海水）和50g机油／kg土的土壤，处理后的水和土壤中残余油量符合国家有关环境污染控制标准，添加油酸钠和H2O2能够显著提高降解效率。
The present paper is aimed at introducing a newly developed method for isolating the lubricating oil-degrading fungi so as to establish a way to use such fungi. In our experiments we have isolated two fungal strains, that is, GXUA and GXUB, from the oil-contaminated soil provided by a motor repairing workshop in Nanning, Guangxi. The above said fungal strains could have grown by using an unused 20 # lubricating oil as the sole carbon and energy source. Both the strains can be identified as the genus Aspergillus according to their morphologies. The analysis of ours was made based on the nucleotide sequence of the internal transcribed spacers （ITS） from the rDNA genes indicating that GXUA and GXUB are homologous to A. tubingensi （Genebank accession No： ATU280008） and A. fumigatus strain SRRC 43 （Genebank accession No： AY373851.1）, respectively. The results gained from the shake-flask fermentation as a uniform design in a system consisting of the oil-containing mineral nutrient fluid prove that the oil degradation efficiency from the mixed mycelia [GXUA（g） ：GXUB（g） = 1：1 ] is significantly higher than that obtained with mycelia of an individual isolate, and that the optimal conditions for the mixed mycelia to degrade the oil are as follows： 25 g mycelia/L, pH = 5.0, and 26 ℃ . At the optimal conditions, the degradation efficiency can be as high as 95.90% for a 9-day treatment of 10 g oil/L. Besides, the analysis done by using liquid chromatography-mass spectrography indicated that such mixed mycelia could degrade 700-900 Dt of the macromolecules in the oil. In addition, we have made a type of laboratory-scale granular （1 cm in diameter） biopreparate from the mixed conidia [ GXUA（spore）： GXUB （spore） = 1：1] and other two kinds of biomaterials. The water （either tap water or seawater） with an about 2 mm thickness of the lubricating oil layer and lubricating oil-contaminated soil （50 g/kg of soil ） were treated in the laboratory-scale, by using biopreparate, 500 granules/m^2 of water surface and 150 granules/kg of soil, respectively. The results of the treatment indicate that the oil content both in the water and in the soil proves to be in conformity with the standard of the state environmental pollution control regulations. The oil degradation efficiency has thus been raised significantly in the presence of a mixture of sodium oleate and hydrogen peroxide.
出处
《安全与环境学报》
CAS
CSCD
2006年第4期9-13,共5页
Journal of Safety and Environment
关键词
应用微生物学
曲霉属
机械润滑油
降解
生物制剂
applied microbiology
Aspergillus
lubricating oil
degradation
biopreparate
