Isolation and Identification of Bacteria from Biofilm with Culture Medium of Low Nutrient Concentration

Abstract:

On the solid surface of indoor moist environment bacteria grow to form biofilms easily, which are hard to remove because of its high adhesion. It is of great microbiological safety significance to research bacteria in such kind of biolfilms. Here we isolated bacteria from biofilm growing on solid surface of a public bathroom with Luria Bertani medium (LB) and its 10-fold diluted medium (LB/10). We found that the biodiversity of bacteria growing on LB/10 was better than that of LB. Furthermore one species of bacterium overgrowing other bacteria phenomena was observed on LB but not on LB/10. Eight strains of bacteria isolated with LB1/10 were identified by 16S rDNA analysis. They are clustered with some clinical isolates and uncultured bacteria. Considering the growing environment of these bacteria we also tested their detergent-degrading ability, and found that they could decrease the quantity of foam caused by detergent.