Browsing by Author "Tseng, CP"

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Biodegradation of hydrogen sulfide by a laboratory-scale immobilized Pseudomonas putida CH11 biofilter
(1996-11-01)
Chung, YC
;
Huang, CP
;
Tseng, CP
;
環境工程研究所
;
生物科技學系
A heterotrophic Pseudomonas putida CH11 was isolated from livestock farming wastewater and applied for the treatment of H2S-containing gas. Extensive tests including removal characteristics, metabolic products, and removal efficiencies of H2S by P. putida CH11 were examined in batch and continuous systems. The optimum pH required to remove hydrogen sulfide was found in the range of 6-8. The maximum removal rate and the saturation constant were calculated to be V-m=1.36 g S/day . kg dry bead and K-s=45.9 ppm, respectively. The main metabolic product of H2S oxidation was determined to be elemental sulfur. When P. putida CH11 was immobilized within Ca alginate, the cells exhibited high H2S removal efficiency, in excess of 96%, at concentrations of hydrogen sulfide from 10 to 150 ppm (now rates of 36 and 72 L/h). These results suggest that P. putida CH11 immobilized within Ca alginate has the potential to be used as a H2S removal agent.
Biological elimination of H2S and NH3 from wastegases by biofilter packed with immobilized heterotrophic bacteria
(2001-06-01)
Chung, YC
;
Huang, CP
;
Tseng, CP
;
環境工程研究所
;
生物科技學系
Biotreatment of various ratios of H2S and NH3 gas mixtures was studied using the biofilters, packed with co-immobilized cells (Arthrobacter oxydans CH8 for NH3 and Pseudomonas putida CH11 for H2S). Extensive tests to determine removal characteristics, removal efficiency, removal kinetics, and pressure drops of the biofilters were performed. To estimate the largest allowable inlet concentration, a prediction model was also employed. Greater than 95% and 90% removal efficiencies were observed for NH3 and H2S, respectively, irrespective of the ratios of H2S and NH3 gas mixtures. The results showed that H2S removal of the biofilter was significantly affected by high inlet concentrations of H2S and NH3. As high H2S concentration was an inhibitory substrate for the growth of heterotrophic sulfur-oxidizing bacteria, the activity of H2S oxidation was thus inhibited. In the case of high NH3 concentration, the poor H2S removal efficiency might be attributed to the acidification of the biofilter. The phenomenon was caused by acidic metabolite accumulation of NH3. Through kinetic analysis, the presence of NH3 did not hinder the NH3 removal, but a high H2S concentration would result in low removal efficiency, Conversely, H2S of adequate concentrations would favor the removal of incoming NH3. The results also indicated that maximum inlet concentrations (model-estimated) agreed well with the experimental values for space velocities of 50-150 h(-1). Hence, the results would be used as the guideline for the design and operation of biofilters. (C) 2001 Elsevier Science Ltd. All rights reserved.
Biotreatment of ammonia from air by an immobilized Arthrobacter oxydans CH8 biofilter
(1997-11-01)
Chung, YC
;
Huang, CP
;
Tseng, CP
;
環境工程研究所
;
生物科技學系
A heterotrophic Arthrobacter oxydans CH8 that was capable of removing NH3 from NH3 containing gas was isolated from livestock farming wastewater. The A. oxydans CH8 was immobilized with calcium alginate packed into filter column. Metered NH3-containing gas was partially humidified and passed through the glass column. Extensive tests including the removal characteristics, the removal efficiencies, and the metabolic products of NH3 by A. oxydans CH8 were conducted. Additionally, the operation criteria for the biofilter was also established. NH3 removal capacities were elevated by the immobilized-cell (biological conversion) method and the BDST (bed depth service time) method (physical adsorption), respectively. The optimum temperature for removing NH3 was 30 degrees C, while the nitrification ability remained 80% at 40 degrees C. The high efficiency (>97%) in the removal of NH3 was attained at 36 L/h with pH control and was not decreased because of high NH3 inlet concentration. In addition, the high maximum removal rate (1.22 g of N/day.(kg of bead)) enhanced the use of the biofilter in industrial-scale NH3(g) pollution control. The ability to remove NH3 at high inlet concentration and temperature suggested that the immobilized A. oxydans CH8 biofilter has potential in processing NH3 gas.
Biotreatment of ammonia from air by an immobilized Arthrobacter oxydans CH8 biofilter
(1997-11-01)
Chung, YC
;
Huang, CP
;
Tseng, CP
;
環境工程研究所
;
生物科技學系
A heterotrophic Arthrobacter oxydans CH8 that was capable of removing NH3 from NH3 containing gas was isolated from livestock farming wastewater. The A. oxydans CH8 was immobilized with calcium alginate packed into filter column. Metered NH3-containing gas was partially humidified and passed through the glass column. Extensive tests including the removal characteristics, the removal efficiencies, and the metabolic products of NH3 by A. oxydans CH8 were conducted. Additionally, the operation criteria for the biofilter was also established. NH3 removal capacities were elevated by the immobilized-cell (biological conversion) method and the BDST (bed depth service time) method (physical adsorption), respectively. The optimum temperature for removing NH3 was 30 degrees C, while the nitrification ability remained 80% at 40 degrees C. The high efficiency (>97%) in the removal of NH3 was attained at 36 L/h with pH control and was not decreased because of high NH3 inlet concentration. In addition, the high maximum removal rate (1.22 g of N/day.(kg of bead)) enhanced the use of the biofilter in industrial-scale NH3(g) pollution control. The ability to remove NH3 at high inlet concentration and temperature suggested that the immobilized A. oxydans CH8 biofilter has potential in processing NH3 gas.
Biotreatment of H2S- and NH3-containing waste gases by co-immobilized cells biofilter
(2000-08-01)
Chung, YC
;
Huang, CP
;
Tseng, CP
;
Pan, JR
;
環境工程研究所
Gas mixture of H2S and NH3 in this study has been the focus in the research area concerning gases generated from the animal husbandry and the anaerobic wastewater lagoons used for their treatment. A specific microflora (mixture of Thiobacillus thioparus CH11 for H2S and Nitrosomonas europaea for NH3) was immobilized with Ca-alginate and packed inside a glass column to decompose H2S and NH3. The biofilter packed with co-immobilized cells was continuously supplied with H2S and NH3 gas mixtures of various ratios, and the removal efficiency, removal kinetics, and pressure drop in the biofilter was monitored. The results showed that the efficiency remained above 95% regardless of the ratios of H2S and NH3 used. The NH3 concentration has little effect on H2S removal efficiency, however, both high NH3 and H2S concentrations significantly suppress the NH3 removal. Through product analysis, we found that controlling the inlet ratio of the H2S/NH3 could prevent the biofilter from acidification, and, therefore, enhance the operational stability. Conclusions from bioaerosol analysis and pressure drop in the biofilter suggest that the immobilized cell technique creates less environmental impact and improves pure culture operational stability. The criteria for the biofilter operation to meet the current H2S and NH3 emission standards were also established. To reach Taiwan's current ambient air standards of H2S and NH3 (0.1 and 1 ppm, respectively), the maximum inlet concentrations should not exceed 58 ppm for H2S and 164 ppm for NH3, and the residence time be kept at 72 s. (C) 2000 Elsevier Science Ltd. All rights reserved.
Characterization of two populations of mesenchymal progenitor cells in umbilical cord blood
(2006-06-01)
Chang, YJ
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Tseng, CP
;
Hsu, LF
;
Hsieh, TB
;
Hwang, SM
Umbilical cord blood (UCB) is a valuable source for hematopoietic progenitor cell therapy. Moreover, it contains another subset of non-hematopoietic population referred to as mesenchymal progenitor cells (MPCs), which can be ex vivo expanded and differentiated into osteoblasts, chondrocytes and adipocytes. In this study, we successfully isolated the clonogenic MPCs from UCB by limiting dilution method. These cells exhibited two different morphologic phenotypes, including flattened fibroblasts (majority) and spindle-shaped fibroblasts (minority). Both types of MPCs shared similar cell surface markers except CD90 and had similar osteogenic and chondrogenic potentials. However, the spindle-shaped clones possessed the positive CD90 expression and showed a greater tendency in adipogenesis, while the flattened clones were CD90 negative cells and showed a lower tendency in adipogenesis. The high number of flattened MPCs might be linked to the less sensitivity of UCB-derived MPCs in adipogenic differentiation. (c) 2006 International Federation for Cell Biology. Published by Elsevier Ltd. All rights reserved.
Comparison of autotrophic and mixotrophic biofilters for H2S removal
(1998-04-01)
Chung, YC
;
Huang, CP
;
Pan, JR
;
Tseng, CP
;
環境工程研究所
We demonstrate that the facultative chemoautotroph Thiobacillus novellus CH3 removes hydrogen sulfide (H2S) gas in continuous reactors under nutrient-limiting conditions. Extensive tests including removal characteristics, metabolic products, and removal efficiencies of H2S by T. novellus CH3 were conducted in autotrophic and mixotrophic environments. The optimal pH value and temperature required to remove hydrogen sulfide are found to be pH 7 and 26 degrees C. The biofilter had an H2S removal efficiency greater than 99.5% under the mixotrophic condition after l0-day operation. The results show that the maximum removal rate and saturation constant were 1.9 g S/d per kg bead and 69.2 ppm, respectively. The main metabolic product of H2S oxidation was determined to be sulfate, but the conversion ratio was dependent on the growth environment. These results suggest that the mixotrophic potential of T. novellus CH3 biofilter provides a significant advantage in HS removal over autotrophic biofilters.
Control of H2S waste gas emissions with a biological activated carbon filter
(2004-06-01)
Chung, YC
;
Lin, YY
;
Tseng, CP
;
生物科技學系
;
Department of Biological Science and Technology
The removal of high concentrations of H2S from waste gases containing mixtures of H2S and NH3 was studied using the pilot-scale biofilter. Granular activated carbon (GAC), selected as support material in this study, demonstrated its high adsorption capacity for H2S and good gas distribution. Extensive tests to determine removal characteristics, removal efficiency, and removal capacity of high H2S levels and coexisting NH3 in the system were performed. In seeking the appropriate operating conditions, the response surface methodology (RSM) was employed. H2S removal capacities were evaluated by the inoculated bacteria (biological conversion) and BDST (Bed Depth Service Time) methods (physical adsorption). An average 98% removal efficiency for 0.083-0.167 mg dm(-3) of H2S and 0.004-0.021 mg dm(-3) of NH3 gases was achieved during the operational period because of rapid physical adsorption by GAC and subsequently an effective biological regeneration of GAC by inoculated Pseudomonas putida CH11 and Arthrobacter oxydans CH8. The results showed that H2S removal efficiency for the system was not affected by inlet NH3 concentrations. In addition, no acidification was observed in the BAC biofilter. High buffer capacity and low moisture demand were also advantages of this system. The maximal inlet loading and critical loading for the system were 18.9 and 7.7 g-H2S m(-3) h(-1), respectively. The results of this study could be used as a guide for the further design and operation of industrial-scale systems. (C) 2004 Society of Chemical Industry.
Effects of glucose on Chinese hamster ovary cells growth and physiology.
(1998-11-01)
Tseng, CP
;
Chen, CL
;
Hwang, SM
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生物科技學系
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Department of Biological Science and Technology
Effects of glucose on Chinese hamster ovary cells growth and physiology.
(1998-11-01)
Tseng, CP
;
Chen, CL
;
Hwang, SM
;
生物科技學系
;
Department of Biological Science and Technology
Growth rate control of fumarase (fumA) gene expression in Escherichia coli
(1997-07-31)
Tseng, CP
;
Yu, CC
;
Hwang, SM
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交大名義發表
;
National Chiao Tung University
Growth rate regulation of lac operon expression in Escherichia coli is cyclic AMP dependent
(2003-10-23)
Kuo, JT
;
Chang, YJ
;
Tseng, CP
;
生物科技學系
;
Department of Biological Science and Technology
In contrast to the ribosomal RNA gene expression increasing with growth rate, transcription of the lac operon is downregulated by cell growth rate. In continuous culture, growth rate regulation of lac promoter was independent of carbon substrate used and its location on the chromosome. Since the lac operon is activated by cyclic adenosine monophosphate (cAMP), which decreases with increasing cell growth rate, expression of plac-lacZ reporter fusion was analyzed in cya mutant under various growth conditions. The results demonstrated that expression of plac-lacZ in cya mutant was both lower and growth rate independent. In addition, ppGpp (guanosine tetraphosphate) was not involved in the mechanism of growth rate regulation of the lac promoter. Thus, the results of this study indicate that cAMP mediates the growth rate-dependent regulation of lac operon expression in Escherichia coli. (C) 2003 Published by Elsevier B.V. on behalf of the Federation of European Biochemical Societies.
Hydrogen sulfide gas treatment by a chemical-biological process: Chemical absorption and biological oxidation steps
(2003)
Chung, YC
;
Ho, KL
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Tseng, CP
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生物科技學系
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Department of Biological Science and Technology
In order to remove high concentrations of hydrogen sulfide (H2S) gas from anaerobic wastewater treatments in livestock farming, a novel process was evaluated for H2S gas abatement involving the combination of chemical absorption and biological oxidation processes. In this study, the extensive experiments evaluating the removal efficiency, capacity, and removal characteristics, of H2S gas by the chemical absorption reactor were conducted in a continuous operation. In addition, the effects of initial Fe2+, concentrations, pH, and glucose concentrations on Fe2+ oxidation by Thiobacillus ferrooxidans CP9 were also examined. The results showed that the chemical process exhibited high removal efficiencies with H2S concentrations up to 300 ppm, and nearly no acclimation time was required. The limitation of mass-transfer was verified as the rate-determining step in the chemical reaction through model validation. The Fe2+ production rate was clearly affected by the inlet gas concentration as well as flow rate and a prediction equation of ferrous production was established. The optimal operating conditions for the biological oxidation process were below pH 2.3 and 35degreesC in which more than 90% Fe3+ formation ratio was achieved. Interestingly, the optimal glucose concentration in the medium was 0.1%, which favored Fe2+ oxidation and the growth of T ferrooxidans CP9.
Kinetics of hydrogen sulfide oxidation by immobilized autotrophic and heterotrophic bacteria in bioreactors
(1996-10-01)
Chung, YC
;
Huang, CP
;
Tseng, CP
;
環境工程研究所
;
生物科技學系
The kinetics of H2S oxidation in bioreactors with separately packed autotrophic Thiobacillus thioparus CH11 and heterotrophic Pseudomonas putida CH11 were evaluated. The reaction rates were determined to be first-order below 20 ppm, zero-order above 60 ppm, and fractional-order in the intermediate concentration ranges for the Thiobacillus thioparus CH11 bioreactor, the first-order below 35 ppm, zero-order above 80 ppm, and fractional-order in the intermediate concentration ranges for the Pseudomonas putida CH11 bioreactor. The saturation constants for H2S by Thiobacillus thioparus CH11 and Pseudomonas putida CH11 were calculated to be 30.3 ppm and 44.2 ppm, respectively.
Kinetics of hydrogen sulfide oxidation by immobilized autotrophic and heterotrophic bacteria in bioreactors
(1996-10-01)
Chung, YC
;
Huang, CP
;
Tseng, CP
;
環境工程研究所
;
生物科技學系
The kinetics of H2S oxidation in bioreactors with separately packed autotrophic Thiobacillus thioparus CH11 and heterotrophic Pseudomonas putida CH11 were evaluated. The reaction rates were determined to be first-order below 20 ppm, zero-order above 60 ppm, and fractional-order in the intermediate concentration ranges for the Thiobacillus thioparus CH11 bioreactor, the first-order below 35 ppm, zero-order above 80 ppm, and fractional-order in the intermediate concentration ranges for the Pseudomonas putida CH11 bioreactor. The saturation constants for H2S by Thiobacillus thioparus CH11 and Pseudomonas putida CH11 were calculated to be 30.3 ppm and 44.2 ppm, respectively.
Microbial oxidation of hydrogen sulfide with biofilter
(1996)
Chung, YC
;
Huang, CP
;
Tseng, CP
;
環境工程研究所
;
生物科技學系
A heterotrophic Pseudomonas putida CH11, isolated from the pig feces and wastewater, was immobilized with Ca-alginate to provide as a packing material in a novel and practical biofilter system for the control of hydrogen sulfide. Extensive tests have been conducted to evaluate the effect of the operating parameters such as temperature, retention time, and gas concentration on the removal efficiency of hydrogen sulfide. The criterion for a scale-up design of biofilter was established. The high removal efficiencies of hydrogen sulfide were observed in the initial hours from the history of removal efficiency and a satisfactory level of removal efficiency could maintain for one week at least. The maximum inlet loading in the linear region was found to be 1.9 g-S/d . kg dry bead. At economically viable retention time of 28 seconds, the biofilter could reduce over 97% hydrogen sulfide. The results suggested that the Pseudomonas putida CH11 immobilized with Ca-alginate could be a potential method to remove hydrogen sulfide.
Operation optimization of Thiobacillus thioparus CH11 biofilter for hydrogen sulfide removal
(1996-11-29)
Chung, YC
;
Huang, CP
;
Tseng, CP
;
環境工程研究所
;
生物科技學系
Members of the autotrophic species, Thiobacillus thioparus CH11, were isolated from swine wastewater and immobilized with Ca-alginate to produce pellet packing materials for a novel biofilter system that controls hydrogen sulfide emission. The effect of operating parameters, including retention time, temperature, and inlet gas concentration, on the removal efficiency and capacity was evaluated. Criteria necessary for a scale-up design of the biofilter were established and the sulfur balances at various loadings were tabulated. High and satisfactory H2S removal efficiency levels were maintained during operation and the optimal retention time was found to be 28 a corresponding to a H2S removal efficiency greater than 98%. The pH drop was insignificant in this biofilter. The optimal inlet S-loading can be noted as 25 g m(-3) h(-1) that is at the upper end of linear correlation between inlet loading and removal capacity. We suggest that the Thiobacillus thioparus CH11 immobilized with Ca-alginate is a potent method to control hydrogen sulfide emissions. Copyright (C) 1996 Elsevier Science B.V.
Operational characteristics of effective removal of H2S and NH3 waste gases by activated carbon biofilter
(2004-04-01)
Chung, YC
;
Lin, YY
;
Tseng, CP
;
生物科技學系
;
Department of Biological Science and Technology
Simultaneous removal of hydrogen sulfide (H,S) and ammonia (NH3) gases from gaseous streams was studied in a biofilter packed with granule activated carbon. Extensive studies, including the effects of carbon (C) source on the growth of inoculated microorganisms and gas removal efficiency, product analysis, bioaerosol emission, pressure drop, and cost evaluation, were conducted. The results indicated that molasses was a potential C source for inoculated cell growth that resulted in removal efficiencies of 99.5% for H2S and 99.2% for NH3. Microbial community observation by scanning electron microscopy indicated that granule activated carbon was an excellent support for microorganism attachment for long-term waste gas treatment. No disintegration or breakdown of biofilm was found when the system was operated for 140 days. The low bioaerosol concentration emitted from the biofilter showed that the system effectively avoided the environmental risk of bioaerosol emission. Also, the system is suitable to apply in the field because of its low pressure drop and treatment cost. Because NH3 gas was mainly converted to organic nitrogen, and H2S gas was converted to elemental sulfur, no acidification or alkalinity phenomena were found because of the metabolite products. Thus, the results of this study demonstrate that the biofilter is a feasible bioreactor in the removal of waste gases.
Oxygen- and growth rate-dependent regulation of Escherichia coli fumarase (FumA, FumB, and FumC) activity
(2001-01-01)
Tseng, CP
;
Yu, CC
;
Lin, HH
;
Chang, CY
;
Kuo, JT
Escherichia coli contains three biochemically distinct fumarases which catalyze the interconversion of fumarate to L-malate in the tricarboxylic acid cycle, Batch culture studies indicated that fumarase activities varied according to carbon substrate and cell doubling time. Growth rate control of fumarase activities in the wild type and mutants was demonstrated in continuous culture; FumA and FumC activities were induced four- to fivefold when the cell growth rate (k) was lowered from 1.2/h to 0.24/h at 1 and 21% O-2, respectively. There was a twofold induction of FumA and FumC activities when acetate was utilized instead of glucose as the sole carbon source. However, these fumarase activities were still shown to be under growth rate control. Thus, the activity of the fumarases is regulated by the cell growth rate and carbon source utilization independently, Further examination of FumA and FumC activities in a cya mutant suggested that growth rate control of FumA acid FumC activities is cyclic AMP dependent, Although the total fumarase activity increased under aerobic conditions, the individual fumarase activities varied under different oxygen levels. While FumB activity was maximal during anaerobic growth (k = 0.6/h), FumA was the major enzyme under anaerobic cell growth, and the maximum activity was achieved when oxygen was elevated to 1 to 2%. Further increase in the oxygen level caused inactivation of FumA and FumB activities by the high oxidized state, but FumC activity increased simultaneously when the oxygen level aas higher than 4%. The same regulation of the activities of fumarases in response to different oxygen levels was also found in mutants. Therefore, synthesis of the three fumarase enzymes is controlled in a hierarchical fashion depending on the environmental oxygen that the cell encounters.
Reduction of H2S/NH3 production from pig feces by controlling environmental conditions
(1996)
Chung, YC
;
Huang, CP
;
Tseng, CP
;
環境工程研究所
;
生物科技學系
The effects of storage temperature and humidity on the malodorous of pig feces was examined in this study. The change of pig feces, including pH, NO3-, SO4=, number of microorganisms, and consumption of oxygen were measured under different conditions. The influence of temperature on the emission of ammonia gas and hydrogen sulfide was monitored by gas detector tubes (GASTEC) periodically under seven storage temperatures(10 degrees C, 15 degrees C, 20 degrees C, 25 degrees C, 30 degrees C, 35 degrees C, and 40 degrees C) and five moisture contents (20%, 40%, 60%, 80%, and 100%). The results showed that the production of NH3 and H2S increased up to 175 ppm and 35 ppm respectively when temperature was above 25 degrees C. The effect of humidity on the production of NH3 and H2S was depended on storage temperature. The maximum production of NH3 and H2S was under 40% humidity at 40 degrees C. In addition, the decline of NH3 and H2S concentration at experimental period were due to physical effect not biological effect because pH decline was caused by H2S(aq) instead of bioconversion into SO4=. The results suggest that the optimal environmental condition to reduce NH3 and H2S production as well as the cost of degas equipment was at 25 degrees C and 60% humidity.