Biodegradation has become a popular alternative remediation technology for its economic and ecological advantages. An aerobic bacterium （strain ZW） capable of degrading α-pinene was isolated from a biofilter by a s...Biodegradation has become a popular alternative remediation technology for its economic and ecological advantages. An aerobic bacterium （strain ZW） capable of degrading α-pinene was isolated from a biofilter by a selective enrichment. Based on the 16S rRNA gene analysis and physiochemical properties, this strain was identified as Pseudomonas veronii. Under the optimized condition achieved by the response surface methodology （RSM）, as well as pH 6.82, temperature 26.3℃ and NaC1 concentration 1.36%, almost 100% α-pinene could be removed within 45 hr. Enzymatic biodegradation by the crude intracellular enzyme could be described well by the Michaelis-Menten model in which the maximum degradation rate Vraax and the half-saturation constant Km were calculated to be 0.431 mmol/（L.min） and 0.169 mmol/L, respectively. Activity assay of catechol suggested that the strain ZW possessed a catechol- 1,2-dioxygenase and could decompose benzene-ring through ortho ring cleavage. Based on the identified intermediates by GC/MS, a new metabolic pathway was proposed, in which the final metabolites were some simpler organic and inorganic compounds. The present work demonstrated that the strain ZW would have a great application prospect for the remediation of α-pinene-contaminated environment.展开更多
基金supported by the National Natural Science Foundation of China (No. 51178431)the International S&T Cooperation Program of China (No.2011DFA92660)+1 种基金the Key Project of Science and Technology Department of Zhejiang Province (No. 2011C13023)Zhejiang Provincial Funds for Distinguished Young Scientists (No. R5090230)
文摘Biodegradation has become a popular alternative remediation technology for its economic and ecological advantages. An aerobic bacterium （strain ZW） capable of degrading α-pinene was isolated from a biofilter by a selective enrichment. Based on the 16S rRNA gene analysis and physiochemical properties, this strain was identified as Pseudomonas veronii. Under the optimized condition achieved by the response surface methodology （RSM）, as well as pH 6.82, temperature 26.3℃ and NaC1 concentration 1.36%, almost 100% α-pinene could be removed within 45 hr. Enzymatic biodegradation by the crude intracellular enzyme could be described well by the Michaelis-Menten model in which the maximum degradation rate Vraax and the half-saturation constant Km were calculated to be 0.431 mmol/（L.min） and 0.169 mmol/L, respectively. Activity assay of catechol suggested that the strain ZW possessed a catechol- 1,2-dioxygenase and could decompose benzene-ring through ortho ring cleavage. Based on the identified intermediates by GC/MS, a new metabolic pathway was proposed, in which the final metabolites were some simpler organic and inorganic compounds. The present work demonstrated that the strain ZW would have a great application prospect for the remediation of α-pinene-contaminated environment.
