The aim of the present study was to investigate the tolerance of five new Achromobacter and Pseudomonas strains to kerosene and to establish if the production of several secondary metabolites increases or not when these bacteria were grown in the presence of kerosene. The biodegradation of kerosene by isolated bacteria was also investigated in this study. Five Proteobacteria were isolated from different samples polluted with petroleum and petroleum products. Based on their morphological, biochemical, and molecular characteristics, isolated bacteria were identified as Achromobacter spanius IBBPo18 and IBBPo21, Pseudomonas putida IBBPo19, and Pseudomonas aeruginosa IBBPo20 and IBBPo22. All these bacteria were able to tolerate and degrade kerosene. Higher tolerance to kerosene and degradation rates were observed for P. aeruginosa IBBPo20 and IBBPo22, compared with that observed for A. spanius IBBPo18 and IBBPo21, and P. putida IBBPo19. All these bacteria were able to produce several secondary metabolites, such as surfactants and pigments. Glycolipid surfactants produced by P. aeruginosa IBBPo20 and IBBPo22, A. spanius IBBPo18 and IBBPo21, and P. putida IBBPo19 have a very good emulsification activity, and their activity increased when they were grown in the presence of kerosene. The production of rhamnolipid surfactants by P. aeruginosa IBBPo20 and IBBPo22 was confirmed by detection of rhlAB gene involved in their biosynthesis. Pyocyanin and pyoverdin pigments were produced only by P. aeruginosa IBBPo20 and IBBPo22, while carotenoid pigments were produced by all the isolated bacteria. Significant changes in pigments production were observed when P. aeruginosa IBBPo20 and IBBPo22, A. spanius IBBPo18 and IBBPo21, and P. putida IBBPo19 were grown in the presence of kerosene. Due to their ability to tolerate and degrade kerosene, and also to produce several secondary metabolites, the isolated bacteria could be used in the bioremediation of kerosene-polluted environments.

中文翻译：

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无色杆菌和假单胞菌种对煤油的耐受性

本研究的目的是研究五种新的无色杆菌和假单胞菌菌株对煤油的耐受性，并确定当这些细菌在煤油中生长时几种次生代谢产物的产量是否增加。这项研究还研究了分离细菌对煤油的生物降解作用。从石油和石油产品污染的不同样品中分离出五种变形杆菌。根据它们的形态，生化和分子特征，分离出的细菌被鉴定为西班牙无色杆菌IBBPo18和IBBPo21，恶臭假单胞菌IBBPo19和铜绿假单胞菌IBBPo20和IBBPo22。所有这些细菌都能够耐受和降解煤油。铜绿假单胞菌IBBPo20和IBBPo22对煤油的耐受性和降解率更高，与观察到的西班牙曲霉IBBPo18和IBBPo21以及恶臭假单胞菌IBBPo19相比。所有这些细菌都能够产生几种次级代谢产物，例如表面活性剂和色素。由铜绿假单胞菌IBBPo20和IBBPo22，西班牙曲霉IBBPo18和IBBPo21以及恶臭假单胞菌IBBPo19产生的糖脂表面活性剂具有非常好的乳化活性，并且当它们在煤油存在下生长时它们的活性增加。铜绿假单胞菌IBBPo20和IBBPo22的鼠李糖脂表面活性剂的生产通过检测参与其生物合成的rhAB基因而得以证实。绿脓杆菌色素和pyoverdin色素仅由铜绿假单胞菌IBBPo20和IBBBo22产生，而类胡萝卜素色素则由所有分离出的细菌产生。当铜绿假单胞菌IBBBo20和IBBBo22，A时，观察到色素产生的显着变化。在煤油的存在下生长了斯潘尼乌斯IBBPo18和IBBPo21，以及恶臭假单胞菌IBBPo19。由于它们具有耐受和降解煤油的能力，并且还具有产生几种次级代谢产物的能力，因此分离出的细菌可用于煤油污染环境的生物修复。