Hydrocarbon-Degrading Bacteria in the Digestive Tract of Fish, their Abundance, Species Composition, and Activity

Abstract

The abundance and species composition of the intestinal bacterioflora of perch, roach, gudgeon, and ruffe from the Curonian Lagoon as well as the activity of their eight bacterial strains in degrading oil hydrocarbons were investigated. The research showed the abundance of bacteria in the intestinal bacteriocenoses of different trophic fish groups investigated to vary with different fish species. With regard to morphological, physiological and biochemical features, isolates from fish intestinal bacteria able to degrade oil hydrocarbons belonged to the genera Aeromonas, Pseudomonas, Flavobacterium, and Micrococcus. Bacteria of the genus Aeromonas made 70% of the total abundance of hydrocarbon-degrading bacteria. It was established that oil hydrocarbons degrading bacteria of the species Aeromonas eucrenophila and Aeromonas media prevail in the digestive tract of the investigated fish. It was also determined that the activity of different bacterial strains in degrading diesel oil differs and varies within a wide range. Bacteria of the genus Aeromonas degraded diesel oil most actively.