Akademik Veri Yönetim Sistemi
FRESENIUS ENVIRONMENTAL BULLETIN, cilt.20, sa.6, ss.1438-1446, 2011 (SCI-Expanded)
In this study, the ability of 2,4-dichlorophenoxyacetic acid (2,4-D) tolerance and degradation of Pseudomonas spp. isolates was investigated. 20 strains of Pseudomonas spp. were tested for their tolerance to 2,4-D. All the strains exhibited variation in sensitivity at 50-1000 ppm 2,4-D concentration but none of the strains were completely inhibited. When compared with the control tubes, all strains exhibited intensive growth but 3 strains (B7, B8, B12), are less intensive than others. P. aeruginosa B I strain was the one with most resistant to 2,4-D concentrations tested. On the contrary, P. fluorescens B7 strain was more sensitive to 2,4-D at these concentrations. Growth of the 20 strains examined remained unaffected at concentrations between 50 and 200 ppm whereas some of the strains showed sensitivity at 850-1000 ppm concentrations. The 20 strains of Pseudomonas spp. were further screened for 2,4-D degrading capacity. Only one strain (B1) having appreciable 2,4-D herbicide degrading capability was selected. Tolerance to and degradation of 2,4-D by B1 was significantly greater than others. The degradation capacity of 2,4-D herbicide of this culture were performed by HPLC. HPLC data analysis has revealed 24, 31, 32, 33% degradation of 2,4-D respectively in 24, 48, 72 and 96 h of incubation at 37 C. HPLC and spectrophotometric measures of the degradation capacity of B1 strain showed that it had the ability to degrade 2,4-D herbicide. This study suggests that resistance to 2,4-D and ability to degradation were achieved through the cells of B1. This strain could be considered as highly beneficial for application of bioremediation of 2,4-D herbicide pollutants.