Biodegradation of isopropanol by a solvent-tolerant Paracoccus denitrificans strain.
The biodegradation of high concentration isopropanol (2-propanol, IPA) at 16 g/L was investigated by a solvent-tolerant strain of bacteria identified as Paracoccus denitrificans for the first time by 16S rDNA gene sequencing. The strain P. denitrificans GH3 was able to utilize the high concentration of IPA as the sole carbon source within a minimal salts medium with a cell density of 1.5×10(8) cells/mL. The optimal conditions were found as follows: initial pH 7.0, incubation temperature 30°C, with IPA concentration 8 g/L. Under the optimal conditions, strain GH3 utilized 90.3% of IPA in 7 days. Acetone, the major intermediate of aerobic IPA biodegradation, was also monitored as an indicator of microbial IPA utilization. Both IPA and acetone were completely removed from the medium following 216 hr and 240 hr, respectively. The growth of strain GH3 on IPA as a sole carbon and energy source was well described by the Andrews model with a maximum growth rate (μmax)=0.0277/hr, a saturation constant (KS)=0.7333 g/L, and an inhibition concentration (Ki)=8.9887 g/L. Paracoccus denitrificans GH3 is considered to be well used in degrading IPA in wastewater.
a Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education , College of Life Sciences, Sichuan University , Chengdu , P.R. China.
Yucong
Y
Geng
Yuanjie
Y
Deng
Feilong
F
Chen
Hong
H
Jin
Ke
K
Tao
Taiping
T
Hou
D019840:2-Propanol / Q000378:metabolism*; D000096:Acetone / Q000378:metabolism; D001673:Biodegradation, Environmental; D003470:Culture Media; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008969:Molecular Sequence Data; D010231:Paracoccus denitrificans / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S; D012997:Solvents / Q000378:metabolism; D013696:Temperature
D003470:Culture Media; D012336:RNA, Ribosomal, 16S; D012997:Solvents; D000096:Acetone; D019840:2-Propanol
Andrews model; Paracoccus denitrificans; acetone; biodegradation; isopropanol (IPA); specific growth rate