Bacteria possessing high capacity to degrade gasoline, kerosene, diesel oil, and lubricating oil were screened from several areas of Hokkaido, Japan. Among isolates, two strains, WatG and HokM, which were identified as new strains of Pseudomonas aeruginosa and Serratia marcescens species, respectively, showed relatively high capacity and wide spectrum to degrade the hydrocarbons in gasoline, kerosene, diesel, and lubricating oil. About 90-95% of excess amount of total diesel oil and kerosene added to mineral salts media as a sole carbon source could be degraded by WatG within 2 and 3 weeks, respectively. The same amount of lubricating oil was 60% degraded within 2 weeks. Strain HokM was more capable than WatG in degrading aromatic compounds in gasoline. This strain could also degrade kerosene, diesel, and lubricating oil with a capacity of 50-60%. Thus, these two isolates have potential to be useful for bioremediation of sites highly contaminated with petroleum hydrocarbons.

Pseudomonas aeruginosa strain WatG was unable to utilize either n-hexatriacontane (C 36 ) or n-tetracontane (C 40 ), which are both insoluble in a mineral salts medium (MSM), as sole carbon source. However, when C 36 and C 40 were added to MSM containing crude oil, more than 25% of each of the compounds was degraded by strain WatG after two weeks at 30°C. These results demonstrate that strain WatG has the ability to degrade long chain alkanes up to C 40 , when they are solubilized by crude oil components.

A novel, oil-degrading bacterium (strain T1) was isolated from a hot spring in Hokkaido, Japan. It efficiently degrades different types of fats and oils, including edible oil waste. When grown in a mineral salt medium containing 1% triacylglycerol (as salad oil), hydrolysis products were 1,3- and 1,2-diacylglycerols, monoacylglycerol, and free fatty acid. However, these products were almost completely consumed during cultivation at 30 degrees C for 5 days, indicating that extracellular lipase acts randomly at different sn-positions of acylglycerols and that strain T1 has a high capacity to utilize free fatty acids. Secreted lipase activity was induced by salad oil and oleic acid. This strain was a Gram-negative straight rod shaped, aerobic, with a polar flagellum, capable of growing in temperature ranges between 15 degrees C and 55 degrees C. The 16S rRNA gene sequence analysis and DNA-DNA hybridization revealed it as a new strain of Pseudomonas aeruginosa. The type strain was T1.

Degradation of n-alkanes in diesel oil by Pseudomonas aeruginosa strain WatG (WatG) was verified in soil microcosms. The total petroleum hydrocarbon (TPH) degradation level in two bioaugmentation samples was 51% and 46% for 1 week in unsterilized and sterilized soil microcosms, respectively. The TPH degradation in the biostimulation was of control level (15%). The TPH degradation in aeration-limited samples was clearly reduced when compared with that in aeration-unlimited ones under both sterilized and unsterilized conditions. Addition of WatG into soil microcosms was accompanied by dirhamnolipid production only in the presence of diesel oil. These findings suggest that degradation of n-alkanes in diesel oil in soil microcosms would be facilitated by bioaugmentation of WatG, with production of dirhamnolipid, and also by participation of biostimulated indigenous soil bacteria

Inaccurate interpretation of blood culture may falsely guide treatment and also has long-term policy implications. The combination of clinical and microbiological knowledge, patient's clinical history and laboratory findings are essential for appropriate interpretation of blood culture.