Isolation and screening of microorganisms capable of degrading nicosulfuron in water

In order to screen and isolate microorganisms capable of degrading nicosulfuron, five strains of microorganisms coded as YF1, YB1, YB2, YB3, and YB4 that can take nicosulfuron as the only source of carbon, nitrogen, and energy were obtained by enrichment culture.Of the five strains, YF1 was a fungus and the others were bacteria. All of the microorganisms were inoculated into the culture media with different concentrations of nicosulfuron and shaking culture was performed for 5 days at 30°C and 150 r·min⁻¹. High Performance Liquid Chromatography (HPLC) was used to detect the concentration of nicosulfuron and calculate the degradation efficiency. The results showed that the degradation rates of the five strains of microorganisms were higher in low concentrations than in high concentrations of nicosulfuron. YF1 had the highest degradation rate of 80.31%, followed by YB1 and YB2 with degradation rates of 78.18% and 73.72%, respectively. However, YB3 and YB4 had lower degradation rates of 36.82% and 25.75%, respectively. Upon primary identification of the three strains of microorganisms with higher degradation rates, it was discovered that YF1 was Aspergillus niger, while YB1 and YB2 were Bacillus sp. __________ Translated from Chinese Journal of Pesticide Science, 2007, 9(3): 275–279 [译自: 农药学学报]