TY - JOUR
T1 - Enhanced biodegradation of β- and δ-hexachlorocyclohexane in the presence of α- and α-isomers in contaminated soils
AU - Kumar, Manish
AU - Chaudhary, Pankaj
AU - Dwivedi, Manish
AU - Kumar, Ranjan
AU - Paul, Debarati
AU - Jain, Rakesh K.
AU - Garg, Satyendra K.
AU - Kumar, Ashwani
PY - 2005/6/1
Y1 - 2005/6/1
N2 - The chlorinated insecticide hexachlorocyclohexane (HCH) has been used extensively in the past, and contaminated sites are present throughout the world. Toward their bioremediation, we isolated a bacterium Pseudomonas aeruginosa ITRC-5 that mediates the degradation of all the four major isomers of HCH under aerobic conditions, both in liquid-culture and contaminated soils. In liquid-culture, the degradation of α- and γ-HCH is rapid and is accompanied with the release of 5.6 μmole chloride ions and 4.1 μmole CO2mole-1 HCH-isomer. The degradation of β- and δ5-isomers is slow, accompanied with the release of 0.9 μmole chloride ions μmole-1 HCH-isomer, and results in a transient metabolite 2,3,4,5,6-pentachlorocyclohexan-1-ol. The strain ITRC-5 also mediates the degradation of α-, β-, γ, and <5-isomers in contaminated soils, where degradation of otherwise persistent β- and <3-HCH is enhanced severalfold inthe presence of α- or γ-HCH. The degradation of soil-applied β- and <3-HCH under aerobic conditions has not been reported earlier. The isolate ITRC-5 therefore demonstrates potential for the bioremediation of HCH-wastes and contaminated soils.
AB - The chlorinated insecticide hexachlorocyclohexane (HCH) has been used extensively in the past, and contaminated sites are present throughout the world. Toward their bioremediation, we isolated a bacterium Pseudomonas aeruginosa ITRC-5 that mediates the degradation of all the four major isomers of HCH under aerobic conditions, both in liquid-culture and contaminated soils. In liquid-culture, the degradation of α- and γ-HCH is rapid and is accompanied with the release of 5.6 μmole chloride ions and 4.1 μmole CO2mole-1 HCH-isomer. The degradation of β- and δ5-isomers is slow, accompanied with the release of 0.9 μmole chloride ions μmole-1 HCH-isomer, and results in a transient metabolite 2,3,4,5,6-pentachlorocyclohexan-1-ol. The strain ITRC-5 also mediates the degradation of α-, β-, γ, and <5-isomers in contaminated soils, where degradation of otherwise persistent β- and <3-HCH is enhanced severalfold inthe presence of α- or γ-HCH. The degradation of soil-applied β- and <3-HCH under aerobic conditions has not been reported earlier. The isolate ITRC-5 therefore demonstrates potential for the bioremediation of HCH-wastes and contaminated soils.
UR - http://www.scopus.com/inward/record.url?scp=20044391444&partnerID=8YFLogxK
U2 - 10.1021/es048497q
DO - 10.1021/es048497q
M3 - Article
C2 - 15984776
AN - SCOPUS:20044391444
SN - 0013-936X
VL - 39
SP - 4005
EP - 4011
JO - Environmental Science and Technology
JF - Environmental Science and Technology
IS - 11
ER -