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Recovery of zero-valent gold from cyanide solution by biosorption followed by incineration
Abstracts / Journal of Bioscience and Bioengineering 108 (2009) S75–S95 Reference 1. Lin, C.W., Cheng, Y.W., and Tsai, S.L.: Multisubstrate biodegradation kinetics of MTBE and BTEX mixtures by pseudomonas aeruginosa, Process Biochem. 42, 1211-1217 (2007).
doi:10.1016/j.jbiosc.2009.08.271
EN-P39 Recovery of zero-valent gold from cyanide solution by biosorption followed by incineration
Kwak Inseob,2,3 Bae Min-A,1 and Yun Yeoung-Sang1,2 Division of Semiconductor and Chemical Engineering, Chonbuk National University, Jeonju, Jeonbuk, Republic of Korea,1 Research Institute of Industrial Technology, Chonbuk National University, Jeonju, Jeonbuk, Republic of Korea 2 and Departemnt of Bioprocess Engineering, Chonbuk National University, Jeonju, Jeonbuk, Republic of Korea 3 Recovery of gold(I) ions from a cyanide solution was attempted using waste biomass of Corynebacterium glutamicum from a fermentation industry. To improve the sorption capacity of the biomass, the decarboxylated biosorbent (DCB) was prepared by removing interfering carboxyl groups from the biomass surface. The highest gold(I) uptake values were 30.38 mg g− 1 and 71.73 mg g− 1 for raw biomass and DCB, respectively. To get zero-valent gold, the gold(I)-loaded biosorbent was incinerated. Thermal behavior of the biosorbent was investigated through a thermogravimetric analysis (TGA) under nitrogen and air atmospheres. The elemental analysis suggested that degradation was almost completed in the air atmosphere. The X-ray photoelectron spectroscopy (XPS) study revealed that the ash contained gold, likely in the zero-valent form, with 46.72% (Raw biomass) and 70.72% (DCB) of purity, respectively. Consequently, it was noted that incineration of the gold(I)-loaded biosorbent results in oxidation of waste biomass volume to small quantity of gold-containing ash and at the same time. Hence, incineration can be a practical approach for treatment of waste biomass sludge and an alternative method for recovery of precious metals. References 1. Niu, H. and Volesky, B.: Characteristics of gold biosorption from cyanide solution, J. Chem. Technol. Biotechnol., 74, 778-784 (1999). 2. Vijayaraghavan, K. and Yun, Y.-S.: Utilization of fermentation waste (Corynebacterium glutamicum) for biosorption of Reactive Black 5 from aqueous solution, J. Hazard. Mater., 141, 45-52 (2007).
doi:10.1016/j.jbiosc.2009.08.272
EN-P40 Insight into the sugar transport and metabolism in Biphenyl/PCB degrader, Rhodococcus jostii RHA1 Naoto Araki,1 Toru Suzuki,1 Keisuke Miyauchi,2 Daisuke Kasai,1 Eiji Masai,1 and Masao Fukuda1
S93
Nagaoka University of Technology, Department of Bioengineering, Nagaoka, Niigata 940-2188, Japan 1 and Tohoku Gakuin University, Department of Civil and Environmental Engineering, Tagajo, Miyagi 985-8537, Japan 2 Biphenyl and PCB degradation system in Rhodococcus jostii RHA1 is induced by biphenyl, and repressed in the presence of glucose or fructose at the transcriptional level. Previously we showed sucrose and maltose did not cause the repression, suggesting that the transport of glucose and fructose is involved in the repression. We identified the gene encoding histidine-containing phosphocarrier protein in phosphotransferase system (PTS), which is responsible for the transport of fructose into a RHA1 cell but not for that of glucose. In this study, we examined the genes for glucose uptake and its phosphorylation. The results of homology search on RHA1 genome sequence with protein sequences of known glucose transporters suggested two candidate genes, ro02365 and ro06844, which show similarity to major facilitator superfamily (MFS) type transporter, and gene disruption indicated that both genes are involved in glucose uptake. Four candidates for glucokinase genes were found in the RHA1 genome, and each disruption mutant of these genes was constructed. Only the mutant of the ro04278 gene exhibited a significant reduction in growth on glucose, and showed partial relief of only glucose repression. In conclusion, glucose is transported and phosphorylated by MFS transporters encoded by ro02365 and ro06844 and ro04278-coding glucokinase, respectively, in RHA1. The effector substance, which led to glucose-mediated repression, is appeared to be formed after phosphorylation by ro04278-coding glucokinase. doi:10.1016/j.jbiosc.2009.08.273
EN-P41 Oil degradation in soil by a hydrocarbon assimilating yeast, Yarrowia lipolytica Mayu Fukui,1 Shinji Shiomi,1 Naoki Tanuma,1 Tomohisa Katsuda,1 Naofumi Shiomi,2 and Hideki Yamaji1 Kobe University, Kobe, Hyogo, Japan 1 and Kobe College, Nishinomiya, Hyogo, Japan 2 Recently, oil-contaminated soil has been found in many places, such as illegal dumping sites, abandoned gas-stations/factories, decrepit power plants, etc. The oil-contaminated soil in these places is not only harmful to ecosystem but reduces the value of real-estate because of unpleasant smell and sight. In situ bioremediation is a cost effective method to return such land to its original condition and particularly the use of exogenous microorganisms with high degradation activity has been widely studied to apply in practice. In this study, we evaluated the degradation of a mineral oil, n-hexadecane, by a small amount of hydrocarbon assimilating yeast in a model soil system. Yarrowia lipolytica ATCC-46484 was used and grown at 30 °C for 18 h in YPD medium consisting of 1% yeast extract, 2% Bacto peptone and 2% D-glucose. The cells were harvested and resuspended in YNB medium consisting of 0.67% yeast nitrogen base without amino acids (Difco) at OD600 unit of 0.2. The model soil was prepared in 10 mL glass vessels. 5 g of silica sand was soaked with n-hexadecane-ethanol solution, and then the ethanol was evaporated by keeping the vessels
doi:10.1016/j.jbiosc.2009.08.271
EN-P39 Recovery of zero-valent gold from cyanide solution by biosorption followed by incineration
Kwak Inseob,2,3 Bae Min-A,1 and Yun Yeoung-Sang1,2 Division of Semiconductor and Chemical Engineering, Chonbuk National University, Jeonju, Jeonbuk, Republic of Korea,1 Research Institute of Industrial Technology, Chonbuk National University, Jeonju, Jeonbuk, Republic of Korea 2 and Departemnt of Bioprocess Engineering, Chonbuk National University, Jeonju, Jeonbuk, Republic of Korea 3 Recovery of gold(I) ions from a cyanide solution was attempted using waste biomass of Corynebacterium glutamicum from a fermentation industry. To improve the sorption capacity of the biomass, the decarboxylated biosorbent (DCB) was prepared by removing interfering carboxyl groups from the biomass surface. The highest gold(I) uptake values were 30.38 mg g− 1 and 71.73 mg g− 1 for raw biomass and DCB, respectively. To get zero-valent gold, the gold(I)-loaded biosorbent was incinerated. Thermal behavior of the biosorbent was investigated through a thermogravimetric analysis (TGA) under nitrogen and air atmospheres. The elemental analysis suggested that degradation was almost completed in the air atmosphere. The X-ray photoelectron spectroscopy (XPS) study revealed that the ash contained gold, likely in the zero-valent form, with 46.72% (Raw biomass) and 70.72% (DCB) of purity, respectively. Consequently, it was noted that incineration of the gold(I)-loaded biosorbent results in oxidation of waste biomass volume to small quantity of gold-containing ash and at the same time. Hence, incineration can be a practical approach for treatment of waste biomass sludge and an alternative method for recovery of precious metals. References 1. Niu, H. and Volesky, B.: Characteristics of gold biosorption from cyanide solution, J. Chem. Technol. Biotechnol., 74, 778-784 (1999). 2. Vijayaraghavan, K. and Yun, Y.-S.: Utilization of fermentation waste (Corynebacterium glutamicum) for biosorption of Reactive Black 5 from aqueous solution, J. Hazard. Mater., 141, 45-52 (2007).
doi:10.1016/j.jbiosc.2009.08.272
EN-P40 Insight into the sugar transport and metabolism in Biphenyl/PCB degrader, Rhodococcus jostii RHA1 Naoto Araki,1 Toru Suzuki,1 Keisuke Miyauchi,2 Daisuke Kasai,1 Eiji Masai,1 and Masao Fukuda1
S93
Nagaoka University of Technology, Department of Bioengineering, Nagaoka, Niigata 940-2188, Japan 1 and Tohoku Gakuin University, Department of Civil and Environmental Engineering, Tagajo, Miyagi 985-8537, Japan 2 Biphenyl and PCB degradation system in Rhodococcus jostii RHA1 is induced by biphenyl, and repressed in the presence of glucose or fructose at the transcriptional level. Previously we showed sucrose and maltose did not cause the repression, suggesting that the transport of glucose and fructose is involved in the repression. We identified the gene encoding histidine-containing phosphocarrier protein in phosphotransferase system (PTS), which is responsible for the transport of fructose into a RHA1 cell but not for that of glucose. In this study, we examined the genes for glucose uptake and its phosphorylation. The results of homology search on RHA1 genome sequence with protein sequences of known glucose transporters suggested two candidate genes, ro02365 and ro06844, which show similarity to major facilitator superfamily (MFS) type transporter, and gene disruption indicated that both genes are involved in glucose uptake. Four candidates for glucokinase genes were found in the RHA1 genome, and each disruption mutant of these genes was constructed. Only the mutant of the ro04278 gene exhibited a significant reduction in growth on glucose, and showed partial relief of only glucose repression. In conclusion, glucose is transported and phosphorylated by MFS transporters encoded by ro02365 and ro06844 and ro04278-coding glucokinase, respectively, in RHA1. The effector substance, which led to glucose-mediated repression, is appeared to be formed after phosphorylation by ro04278-coding glucokinase. doi:10.1016/j.jbiosc.2009.08.273
EN-P41 Oil degradation in soil by a hydrocarbon assimilating yeast, Yarrowia lipolytica Mayu Fukui,1 Shinji Shiomi,1 Naoki Tanuma,1 Tomohisa Katsuda,1 Naofumi Shiomi,2 and Hideki Yamaji1 Kobe University, Kobe, Hyogo, Japan 1 and Kobe College, Nishinomiya, Hyogo, Japan 2 Recently, oil-contaminated soil has been found in many places, such as illegal dumping sites, abandoned gas-stations/factories, decrepit power plants, etc. The oil-contaminated soil in these places is not only harmful to ecosystem but reduces the value of real-estate because of unpleasant smell and sight. In situ bioremediation is a cost effective method to return such land to its original condition and particularly the use of exogenous microorganisms with high degradation activity has been widely studied to apply in practice. In this study, we evaluated the degradation of a mineral oil, n-hexadecane, by a small amount of hydrocarbon assimilating yeast in a model soil system. Yarrowia lipolytica ATCC-46484 was used and grown at 30 °C for 18 h in YPD medium consisting of 1% yeast extract, 2% Bacto peptone and 2% D-glucose. The cells were harvested and resuspended in YNB medium consisting of 0.67% yeast nitrogen base without amino acids (Difco) at OD600 unit of 0.2. The model soil was prepared in 10 mL glass vessels. 5 g of silica sand was soaked with n-hexadecane-ethanol solution, and then the ethanol was evaporated by keeping the vessels