title: Effect of four dispersants on biodegradation and growth of bacteria on crude oil.
abstract: Four chemical dispersants, Corexit 8666, Gamlen Sea Clean, G. H. Woods Degreaser-Formula 11470, and Sugee 2 were examined singly and in individual combinations with Arabian Crude Oil (1:1 ratio) at 10 and 25 C for their effects on the growth of bacteria indigenous to local marine waters, the bacterial population composition, and biodegradation of crude oil; in addition, their emulsifying capacities, at approximately 24 C, were determined. None of the dispersants used alone were toxic even at relatively high concentrations (1.25%), although Gamlen Sea Clean and G. H. Woods Degreaser-Formula 11470 did cause an increase in the lag phase which was more pronounced at 10 than at 25 C; addition of the crude oil reduced the lag phase increase. All of the dispersants used alone supported good growth of microorganisms, but qualitative population shifts were caused by the dispersant-oil combinations. The degrees of degradation of the n-alkane fraction of the crude oil varied depending upon the dispersant used. Under these test conditions, only Sugee 2, which had the poorest emulsifying capacity, promoted n-alkane degradation compared with the values obtained by using the crude oil alone.
mesh_terms: D000333:Aeromonas / Q000254:growth & development; D000421:Alcaligenes / Q000254:growth & development; D001419:Bacteria / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002849:Chromatography, Gas; D004755:Enterobacteriaceae / Q000254:growth & development; D005648:Fuel Oils; D010578:Petroleum; D011549:Pseudomonas / Q000254:growth & development; D012623:Seawater; D013501:Surface-Active Agents / Q000494:pharmacology*; D013696:Temperature; D014733:Vibrio / Q000254:growth & development; D014871:Water Microbiology
chemical_list: D005648:Fuel Oils; D010578:Petroleum; D013501:Surface-Active Agents