Optimization of Growth Conditions for Chlorpyrifos-Degrading Bacteria in Farm Soils in Nakuru County, Kenya

Figure 4

Growth patterns of bacteria isolates (OD₆₀₀) and CP degradation (OD₄₈₀) at 25 mg/l (a), 50 mg/l (b), and 100 mg/l (c). The bacteria isolates are as follows: MW1: Alcaligenes faecalis UWI9; MW2: Bacillus weihenstephanensis FB25M; MW3: Bacillus toyonensis 20SBZ2B; MW4: Alcaligenes sp. SCAU23; MW5: Pseudomonas sp. P_B845W; MW6: uncultured bacterium clone 99; MW7: Brevundimonas diminuta CB21. Optical density at 600 nm was used for indirect measurement of bacterial growth, while optical density at 480 nm was used to measure the CP degradation as indicated by the intensity of formazan, a product of tetrazolium breakdown by the bacterial isolates.

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