BIODEGRADATION OF 4-CHLORO-2-METHYLPHENOXYACETIC ACID BY ENDOPHYTIC FUNGUS PHOMOPSIS SP. IN LIQUID MEDIUM AND SOIL

An endophytic fungus strain, newly isolated from Psidium guajava (common guava), could effectively degrade 4-chloro-2-methylphenoxyacetic acid (MCPA).According to the analysis of its phenotypic feature and ITS rDNA gene sequence, the isolated strain was identified as Phomopsis sp. and named E41.The influencing factors including medium pH, temperature, and initial concentration of MCPA affecting the degradation of MCPA by this strain were optimized in this study.The maximum biodegradation rate of 86.89% was obtained after inoculation for 7 days under the optimal conditions with MCPA concentration of 50 mg/L, temperature 30 °C and a pH of 6.The metabolite 4-chloro-2methylphenol was detected by using gas chromatography-mass spectrometry (GC-MS).In the bioremediation experiment, the biodegradation of MCPA was significantly enhanced in all soils with the presence of the strain E41.These results suggested that the strain E41 may have potential value for the bioremediation of MCPA-contaminated environment.