Abstract:

In this paper, 12 strains that utilized cholesterol as sole carbon and energy sources were isolated from the sludge by the enrichment culture method. Four strains were selected for degradation of cholestero1. In the culture conditions of 30℃ and 200 r/min, the degradation rate to cholesterol of 4 strains were 51.25%, 36.65%, 55.62% and 29.59% respectively, with 30 μg/mL concentrations within 96 hours. The suitable pH values for their growth were wide, and the strains went into the stationary phase at the twelfth hour. L4 and L5 strains were identified to be Klebsiella pneumoniae by morphological characteristics and the similarity analysis of the 16S rDNA sequence.