• Journal of Microbiology and Biotechnology
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• v.13 no.6
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• pp.866-871
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• 2003

Malodorous gas of dimethyl sulfide (DMS) was biologically oxidized to sulfate by Thiobacillus thioparus TK-m (DSM5368) immobilized in/on ceramic beads. More than 99.99％ of DMS removal efficiency was obtained in a ceramic-biofilter reactor of 3.91 when the feed concentrations were about 27.5 and 55.0 mg DMS/1 at $30^{circ}C$. However, the removal efficiency of the biofilter at above $40^{circ}C$ decreased to 4.5 mg DMS/(lㆍmin) which was 85％ of that at $30^{circ}C$.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.6
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• pp.375-379
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• 2002

Methyl mercaptan oxidase was successfully induced in Thiobacillus thioparus TK-m using methyl mercaptan gas, and was purified for the detection of mercaptans. The purification procedure Involved a DEAE (diethylaminoethyl) -Sephacel, or Superose 12, column chromatography with recovery yields of 47.5 and 48.5%, and specific activities of 374 and 1240.8 units/mg-protein, respectively, The molecular weight of the purified methyl mercaptan oxidase was 66.1kDa, as determined by SDS-PAGE. The extract, from gel filtration chromatography oxidizes methyl mercaptan, producing formaldehyde, which can be easily detected by the purpald-coloring method. The optimized temperature for activity was found to be at 55$\^{C}$. This enzyme was inhibited by both NH$_4$Cl and (NH$_4$)$_2$SO$_4$, but was unaffected by either KCl or NaCl at less than 200 mM. With K$_2$SO$_4$, the activity decreased at 20 mM, but recovered at 150 mM. In the presence of methanol, full activity was maintained, but decreased in the presence of glycerin, ethanol and acetone 43, 78 and 75%, respectively.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.485-488
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• 2000

Methyl mercaptan oxidase was isolated and purified from Thiobacillus thioparus TK-m for the detection of mercaptans. The procedure of purification involved DEAE-Sephacel and Superose 12 column chromatographies with recovery yields of 47.5 and 48.5 %, and specific activity of 374 and 1240.8 units/mg-protein, respectively. The molecular weight of purified methyl mercaptan oxidase was determined to be 66.1 kDa by SDS-PAGE. Optimum temperature for activity was observed at $55\;^{circ}C$. This enzyme was activated by $(NH_4)_2SO_4$ and NaCl and inhibited by $NH_4Cl$.

• Journal of Environmental Science International
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• v.17 no.1
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• pp.7-17
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• 2008

Simultaneous removal of $NH_3,\;H_2S$ and toluene in a contaminated air stream was investigated over 185 days in a biofilter packed with Zeocarbon granule as microbial support. In this study, multi-microorganisms including Nitrosomonas and Nitrobacter for nitrogen removal, Thiobacillus thioparus (ATCC 23645) for $H_2S$ removal, and Pseudomonas aeruginosa (ATCC 15692), Pseudomonas putida (ATCC 17484) and Pseudomonas putida (ATCC 23973) for toluene removal were used simultaneously. The empty bed residence time (EBRT) was 40-120 seconds and the feed (inlet) concentrations of $NH_3,\;H_2S$ and toluene were 0.02-0.11, 0.05-0.23 and 0.15-0.21 ppmv, respectively. The observed removal efficiency was 85%-99% for $NH_3$, 100% for $H_2S$, and 20-90% for toluene, respectively. The maximum elimination capacities were 9.3, 20.6 and $17g/m^3/hr\;for\;NH_3,\;H_2S$ and toluene, respectively. The results of kinetic model analysis showed that there were no particular evidences of interactions or inhibitions among the microorganisms, and that the three bio degradation reactions took place independently within a finite area of biofilm developed on the surface of the Zeocarbon carrier.

• Environmental Engineering Research
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• v.13 no.1
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• pp.19-27
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• 2008

Simultaneous removal of ternary gases of $NH_3$, $H_2S$ and toluene in a contaminated air stream was investigated over 180 days in a biofilter. A commercially available inorganic/polymeric composite chip with a large void volume (bed porosity > 0.80) was used as a microbial support. Multiple microorganisms including Nitrosomonas and Nitrobactor for nitrogen removal, Thiobacillus thioparus (ATCC 23645) for $H_2S$ removal and Pseudomonas aeruginosa (ATCC 15692), Pseudomonas putida (ATCC 17484) and Pseudomonas putida (ATCC 23973) for toluene removal were used simultaneously. The empty bed residence time (EBRT) ranged from 60 - 120 seconds and the inlet feed concentration was $0.0325\;g/m^3-0.0651\;g/m^3$ for $NH_3$, $0.0636\;g/m^3-0.141\;g/m^3$ for $H_2S$, and $0.0918\;g/m^3-0.383\;g/m^3$ for toluene, respectively. The observed removal efficiency was 2% - 98% for $NH_3$, 2% - 100% for $H^2S$, and 2% - 80% for toluene, respectively. Maximum elimination capacity was about $2.7\;g/m^3$/hr for $NH_3$, > $6.4\;g/m^3$/hr for $H_2S$ and $4.0\;g/m^3$/hr for toluene, respectively. The inorganic/polymeric composite carrier required 40 - 80 days of wetting time for biofilm formation due to the hydrophobic nature of the carrier. Once the surface of the carrier was completely wetted, the microbial activity became stable. During the long-term operation, pressure drop was negligible because the void volume of the carrier was two times higher than the conventional packing materials.