Yi-Tang Chang - Academia.edu (original) (raw)

Papers by Yi-Tang Chang

Research paper thumbnail of Biological treatment of benzophenone-type UV filter wastewater in a sequencing batch reactor (SBR)

International Biodeterioration & Biodegradation

Research paper thumbnail of Photosynthetic purple sulfur bacterium Marichromatium purpuratum RuA2 induces changes in water quality parameters, the occurrence of sulfonamide resistance gene and microbial community structure of marine aquaculture

Aquaculture, 2018

purple sulfur bacterium Marichromatium purpuratum RuA2 induces changes in water quality parameter... more purple sulfur bacterium Marichromatium purpuratum RuA2 induces changes in water quality parameters, the occurrence of sulfonamide resistance gene and microbial community structure of marine aquaculture. The address for the corresponding author was captured as affiliation for all authors. Please check if appropriate. Aqua(2018),

Research paper thumbnail of The Indoor Concentration and Size Distribution of Airborne Bacteria in a Typical Traditional Market

Aerosol and Air Quality Research

Bioaerosols generated by fresh foods in traditional wet markets (TWMs) in Taiwan are classified a... more Bioaerosols generated by fresh foods in traditional wet markets (TWMs) in Taiwan are classified as significant biological contaminants and can lead to biological hazard risk. This study aims to explore the distribution of the different particle sizes of airborne bacteria (AB) present at typical public indoor TWM. The concentrations during operations at the chosen indoor TWM were measured to be 1.55 × 10 3 CFU m-3 of AB. The presence of AB in the environment was influenced by the specific products being sold, particularly in areas where vendors sold fresh poultry and livestock meat. These areas exhibited a higher concentration of AB. Although the AB concentrations were comparable to Taiwan indoor air quality standards, the size distribution of AB indicated a potential biological hazard for the staff working with poultry and livestock meat. The size distribution analysis revealed that the highest frequency of bioaerosols was observed within the range of 2.1 to 3.3 μm, accounting for 25.76% of all AB during TWM operation and 22.79% after operations were completed. The main bacterial source came from the excrement produced by the live poultry around these sampling points. The second highest proportion was in the range of 1.1 to 2.1 μm. These two sizes of particles are highly likely to deposit in the bronchial tubes of the respiratory tract after being inhaled by humans. Among the AB sampled, isolated and identified were Kocuria marina, K. carniphila, and Staphylococcus sciuri, which were frequently found in a typical indoor TWM. We recommend using

Research paper thumbnail of Synthesis of cross-linked magnetic chitosan beads immobilised with bacteria for aerobic biodegrading benzophenone-type UV filter

Research paper thumbnail of Continuous Biodiesel Production from Waste Soybean Oil Using a Nano-Fe3O4 Microwave Catalysis

Processes, 2021

In this study, we conducted an efficient microwave-assisted transesterification process combining... more In this study, we conducted an efficient microwave-assisted transesterification process combining homogeneous and heterogeneous catalytic phases to produce biodiesel from waste soybean oil. A cylindrical quartz reactor packed with nanoparticles of Fe3O4 as a co-catalyst was applied to improve the reaction. The process was carried out with a methanol-to-oil molar ratio of 6:1, power of 560 W, and residence time of 30 s. The specifications of the biodiesel produced in this study were compared with two standards, i.e., ASTM D6751 and EN 14214. We found that the continuous conversion of waste soybean oil to methyl ester was approximately 95%. The biodiesel showed a higher flash point and a higher carbon residue content than that of both standards, and the viscosity (5.356 mm2/s) and density (898.1 kg/m3) were both at a high level. Compared to a conventional heating plate, the energy consumption was significantly reduced by nearly 93%. It is expected that these findings will provide usef...

Research paper thumbnail of 利用生物淋溶法提高底泥難分解有機污染物之生物復育-以多苯環化合物為例(2/2)

Research paper thumbnail of Bacterial community and physiological characteristics of octylphenol polyethoxylate biodegradation in soil slurries

Applied Soil Ecology, 2022

Research paper thumbnail of Degradation of Decabromodiphenyl Ether in an Aerobic Clay Slurry Microcosm Using a Novel Immobilization Technique

Microorganisms, 2022

A novel chitosan immobilization technique that entraps photocatalyst and microbes was developed a... more A novel chitosan immobilization technique that entraps photocatalyst and microbes was developed and applied to decompose decabromodiphenyl ether (BDE-209) in a clay slurry microcosm. The optimized conditions for immobilization were obtained by mixing 1.2% (w/v) chitosan dissolved in 1% (v/v) acetic acid with nano-TiO2 particles and the BDE-209-degrading bacterial mixed culture. This aqueous mixture was injected into 1% (w/v) water solution containing sodium tripolyphosphate to form spherical immobilized beads. The surface of the immobilized beads was reinforced by 0.25% (v/v) glutaraldehyde cross-linking. These beads had enough mechanical strength during BDE-209 degradation to maintain their shape in the system at a stirring rate of 200-rpm, while undergoing continuous 365 nm UVA irradiation. This novel TiO2-Yi-Li immobilized chitosan beads system allowed a successful simultaneous integration of photolysis, photocatalysis and biodegradation to remove BDE-209. The remaining percentag...

Research paper thumbnail of 化學傳輸行為對土壤微生物分解多環芳香烴化合物之影響; Fates impact on PAH biodegradation in the soil/water system with surfactants

Research paper thumbnail of Effects of Malachite Green on the Microbiomes of Milkfish Culture Ponds

Water

Intensive fish farming through aquaculture is vulnerable to infectious diseases that can increase... more Intensive fish farming through aquaculture is vulnerable to infectious diseases that can increase fish mortality and damage the productivity of aquaculture farms. To prevent infectious diseases, malachite green (MG) has been applied as a veterinary drug for various microbial infections in aquaculture settings worldwide. However, little is known regarding the consequences of MG and MG-degrading bacteria (MGDB) on microbial communities in milkfish culture ponds (MCPs). In this study, small MCPs were used as a model system to determine the effects of MG on the microbial communities in MCPs. The addition of MG led to cyanobacterial blooms in the small MCP. The addition of MGDB could not completely reverse the effects of MG on microbial communities. Cyanobacterial blooms were not prevented. Microbial communities analyzed by next generation sequencing revealed that cyanobacterial blooms may be due to increase of nitrogen cycle (including nitrogen fixation, nitrate reduction and anammox) a...

Research paper thumbnail of Aerobic biodegradation of benzophenone-type UV-filter by bacterial strains isolated from WWTP sludge

Research paper thumbnail of A coupled UV photolysis-biodegradation process for the treatment of decabrominated diphenyl ethers in an aerobic novel bioslurry reactor

Environmental Science and Pollution Research

The commercial flame retardant is an emerging contaminant (EC) commonly found in soils and sedime... more The commercial flame retardant is an emerging contaminant (EC) commonly found in soils and sediments. A coupled UVphotolysis-biodegradation process was used to decompose decabromodiphenyl ether (BDE-209) in clay slurries. A novel bioslurry bioreactor (NBB) was employed in which BDE-209 degradation was maximized by the simultaneous application of LED UVA irradiation and biodegradation by a mixed bacterial culture. The rate of BDE-209 degradation decreased in the order: coupled UV photolysis-biodegradation (1.31 × 10-2 day-1) > UV photolysis alone (1.10 × 10-2 day-1) > biodegradation alone (1.00 × 10-2 day-1). Degradation intermediates detected included hydroxylated polybrominated diphenylethers, partially debrominated PBDE congeners and polybrominated dibenzofuran. The UV-resistant bacterial strains isolated that could utilize BDE-209 as a sole carbon source included Stenotrophomonas sp., Pseudomonas sp., and Microbacterium sp. These strains encoded important functional genes such as dioxygenase and reductive dehalogenases. Continuous UV irradiation during the NBB process affected various biochemical oxidative reactions during PBDEs biodegradation. Simultaneous photolysis and biodegradation in the NBB system described reduces operational time, energy, expense, and maintenance-demands required for the remediation of BDE-209 when compared to sequential UV-biodegradation process or to biodegradation alone. Keywords Coupled UV photolysis-biodegradation. Decabromodiphenyl ether. Novel bioslurry bioreactor. UV-resistant bacterial strains. Polybrominated dibenzofuran Highlights • A time, energy, and cost-saving technique using a coupled UV photolysis-biodegradation process for degrading BDE-209 in a novel bioslurry bioreactor. • Identification of isolated UV-resistant bacterial strains that potentially are able to utilize PBDEs as sole carbon source and the analysis of related functional genes. • The prediction of a possible pathway for BDE-209 degradation by coupled photolysis-biodegradation.

Research paper thumbnail of An Investigation of Airborne Bioaerosols and Endotoxins Present in Indoor Traditional Wet Markets before and after Operation in Taiwan: A Case Study

International Journal of Environmental Research and Public Health

Customers in Taiwan prefer to purchase fresh foods and household supplies at indoor traditional w... more Customers in Taiwan prefer to purchase fresh foods and household supplies at indoor traditional wet markets (TWMs). The health risk to indoor TWM staff exposed to bioaerosols needs to be evaluated, since these workers spend long periods of time in the market for stall preparation, selling, and stall cleaning. This study investigated the bioaerosols present in two indoor TWMs. The results showed that the cleaning process at Market A after operations, involving the use of an agitated waterspout, was able to decrease the concentration of bacterial bioaerosols (BBs) by an average of 64%, while at the same time increasing the concentration of fungal bioaerosols (FBs) by about 2.4 fold. The chemical sanitization process at Market B after operations was able to bring about average decreases of 30.8% in BBs and 19.2% in FBs, but the endotoxin concentration increased. Hotspots were found to be associated with vendors of fresh, live poultry and fresh, raw meat/seafood. Pseudomonas spp. and Cl...

Research paper thumbnail of Characterization of a Sequential UV Photolysis-Biodegradation Process for Treatment of Decabrominated Diphenyl Ethers in Sorbent/Water Systems

Microorganisms

Decabrominated diphenyl ether (BDE-209) is a primary component of the brominated flame retardants... more Decabrominated diphenyl ether (BDE-209) is a primary component of the brominated flame retardants used in a variety of industrial and domestic applications. BDE-209 bioaccumulates in aquatic organisms and has been identified as an emerging contaminant that threatens human and ecosystem health. Sequential photolysis-microbial biodegradation processes were utilized here to treat BDE-209 in clay- or soil-water slurries. The removal efficiency of BDE-209 in the clay-water slurries was high; i.e., 96.5%, while that in the soil-water slurries was minimal. In the clay-water slurries the first order rate constants for the UV photolysis and biodegradation of BDE-209 were 0.017 1/day and 0.026 1/day, respectively. UV wavelength and intensity strongly influenced the BDE-209 photolysis and the subsequent biodegradation of photolytic products. Facultative chemotrophic bacteria, including Acidovorax spp., Pseudomonas spp., Novosphingobium spp. and Sphingomonas spp., were the dominant members of t...

Research paper thumbnail of Photosynthetic bacteria enhanced water quality and integrity of microbial community composition of integrated multitrophic aquaculture system of milkfish Chanos chanos coastal farming

Research paper thumbnail of Variation of Microbial Communities in Aquatic Sediments under Long-Term Exposure to Decabromodiphenyl Ether and UVA Irradiation

Sustainability

Abiotic components create different types of environmental stress on bacterial communities in aqu... more Abiotic components create different types of environmental stress on bacterial communities in aquatic ecosystems. In this study, the long-term exposure to various abiotic factors, namely a high-dose of the toxic chemical decabromodiphenyl ether (BDE-209), continuous UVA irradiation, and different types of sediment, were evaluated in order to assess their influence on the bacterial community. The dominant bacterial community in a single stress situation, i.e., exposure to BDE-209 include members of Comamonadaceae, members of Xanthomonadaceae, a Pseudomonas sp. and a Hydrogenophaga sp. Such bacteria are capable of biodegrading polybrominated diphenyl ethers (PBDEs). When multiple environmental stresses were present, Acidobacteria bacterium and a Terrimonas sp. were predominant, which equipped the population with multiple physiological characteristics that made it capable of both PBDE biodegradation and resistance to UVA irradiation. Methloversatilis sp. and Flavisolibacter sp. were id...

Research paper thumbnail of Effects of sulfamethoxazole and sulfamethoxazole-degrading bacteria on water quality and microbial communities in milkfish ponds

Research paper thumbnail of Investigation of a Farm-scale Multitrophic Recirculating Aquaculture System with the Addition of Rhodovulum sulfidophilum for Milkfish (Chanos chanos) Coastal Aquaculture

Sustainability

Globally, coastal aquaculture is growing due to the large demand for marine products. Specific im... more Globally, coastal aquaculture is growing due to the large demand for marine products. Specific impacts caused by coastal aquaculture on the environment include the discharge of culture farm effluents, stress on ground water (the absence of recycling), nutrient pollution, and diseases of cultured animals. Three methods, integrated multitrophic aquaculture (IMTA), recirculating aquaculture system (RAS), and beneficial bacteria for aquaculture, have been developed to solve these problems. In this study, the advantages of IMTA and RAS were integrated to develop a novel multitrophic recirculating aquaculture system (MRAS) to adapt to the farm-scale culturing of milkfish (Chanos chanos). The photosynthetic bacteria Rhodovulum sulfidophilum was added to enhance the performance of the farm-scale milkfish MRAS. This setting could promote growth of beneficial bacteria, such as the nitrogen cycle-associated microbial community and the anoxygenic phototrophic Acidobacteria community. The ammoni...

Research paper thumbnail of The effects of marine farm-scale sequentially integrated multi-trophic aquaculture systems on microbial community composition, prevalence of sulfonamide-resistant bacteria and sulfonamide resistance gene sul1

Science of The Total Environment

Research paper thumbnail of A Comparison of the Microbial Community and Functional Genes Present in Free-Living and Soil Particle-Attached Bacteria from an Aerobic Bioslurry Reactor Treating High-Molecular-Weight PAHs

Sustainability

High-molecular-weight (HMW) polycyclic aromatic hydrocarbons (PAHs) contaminate a wide range of e... more High-molecular-weight (HMW) polycyclic aromatic hydrocarbons (PAHs) contaminate a wide range of ecosystems, including soils, groundwater, rivers and harbor sediments. The effective removal of HMW PAHs is a difficult challenge if a rapid remediation time and low economic cost are required. Bioremediation provides a cheap and eco-friendly cleanup strategy for the removal of HMW PAHs. Previous studies have focused on removal efficiency during PAHs bioremediation. In such studies, only limited research has targeted the bacterial communities and functional genes present in such bioremediation systems, specifically those of free-living (aqueous) bacteria and soil particle-attached bacteria present. In this study, a high-level of HMW PAH (1992 mg/kg pyrene) was bioremediated in an aerobic bioslurry reactor (ABR) for 42 days. The results showed a pseudo first order constant rate for pyrene biodegradation of 0.0696 day−1. The microbial communities forming free-living bacteria and soil-attach...

Research paper thumbnail of Biological treatment of benzophenone-type UV filter wastewater in a sequencing batch reactor (SBR)

International Biodeterioration & Biodegradation

Research paper thumbnail of Photosynthetic purple sulfur bacterium Marichromatium purpuratum RuA2 induces changes in water quality parameters, the occurrence of sulfonamide resistance gene and microbial community structure of marine aquaculture

Aquaculture, 2018

purple sulfur bacterium Marichromatium purpuratum RuA2 induces changes in water quality parameter... more purple sulfur bacterium Marichromatium purpuratum RuA2 induces changes in water quality parameters, the occurrence of sulfonamide resistance gene and microbial community structure of marine aquaculture. The address for the corresponding author was captured as affiliation for all authors. Please check if appropriate. Aqua(2018),

Research paper thumbnail of The Indoor Concentration and Size Distribution of Airborne Bacteria in a Typical Traditional Market

Aerosol and Air Quality Research

Bioaerosols generated by fresh foods in traditional wet markets (TWMs) in Taiwan are classified a... more Bioaerosols generated by fresh foods in traditional wet markets (TWMs) in Taiwan are classified as significant biological contaminants and can lead to biological hazard risk. This study aims to explore the distribution of the different particle sizes of airborne bacteria (AB) present at typical public indoor TWM. The concentrations during operations at the chosen indoor TWM were measured to be 1.55 × 10 3 CFU m-3 of AB. The presence of AB in the environment was influenced by the specific products being sold, particularly in areas where vendors sold fresh poultry and livestock meat. These areas exhibited a higher concentration of AB. Although the AB concentrations were comparable to Taiwan indoor air quality standards, the size distribution of AB indicated a potential biological hazard for the staff working with poultry and livestock meat. The size distribution analysis revealed that the highest frequency of bioaerosols was observed within the range of 2.1 to 3.3 μm, accounting for 25.76% of all AB during TWM operation and 22.79% after operations were completed. The main bacterial source came from the excrement produced by the live poultry around these sampling points. The second highest proportion was in the range of 1.1 to 2.1 μm. These two sizes of particles are highly likely to deposit in the bronchial tubes of the respiratory tract after being inhaled by humans. Among the AB sampled, isolated and identified were Kocuria marina, K. carniphila, and Staphylococcus sciuri, which were frequently found in a typical indoor TWM. We recommend using

Research paper thumbnail of Synthesis of cross-linked magnetic chitosan beads immobilised with bacteria for aerobic biodegrading benzophenone-type UV filter

Research paper thumbnail of Continuous Biodiesel Production from Waste Soybean Oil Using a Nano-Fe3O4 Microwave Catalysis

Processes, 2021

In this study, we conducted an efficient microwave-assisted transesterification process combining... more In this study, we conducted an efficient microwave-assisted transesterification process combining homogeneous and heterogeneous catalytic phases to produce biodiesel from waste soybean oil. A cylindrical quartz reactor packed with nanoparticles of Fe3O4 as a co-catalyst was applied to improve the reaction. The process was carried out with a methanol-to-oil molar ratio of 6:1, power of 560 W, and residence time of 30 s. The specifications of the biodiesel produced in this study were compared with two standards, i.e., ASTM D6751 and EN 14214. We found that the continuous conversion of waste soybean oil to methyl ester was approximately 95%. The biodiesel showed a higher flash point and a higher carbon residue content than that of both standards, and the viscosity (5.356 mm2/s) and density (898.1 kg/m3) were both at a high level. Compared to a conventional heating plate, the energy consumption was significantly reduced by nearly 93%. It is expected that these findings will provide usef...

Research paper thumbnail of 利用生物淋溶法提高底泥難分解有機污染物之生物復育-以多苯環化合物為例(2/2)

Research paper thumbnail of Bacterial community and physiological characteristics of octylphenol polyethoxylate biodegradation in soil slurries

Applied Soil Ecology, 2022

Research paper thumbnail of Degradation of Decabromodiphenyl Ether in an Aerobic Clay Slurry Microcosm Using a Novel Immobilization Technique

Microorganisms, 2022

A novel chitosan immobilization technique that entraps photocatalyst and microbes was developed a... more A novel chitosan immobilization technique that entraps photocatalyst and microbes was developed and applied to decompose decabromodiphenyl ether (BDE-209) in a clay slurry microcosm. The optimized conditions for immobilization were obtained by mixing 1.2% (w/v) chitosan dissolved in 1% (v/v) acetic acid with nano-TiO2 particles and the BDE-209-degrading bacterial mixed culture. This aqueous mixture was injected into 1% (w/v) water solution containing sodium tripolyphosphate to form spherical immobilized beads. The surface of the immobilized beads was reinforced by 0.25% (v/v) glutaraldehyde cross-linking. These beads had enough mechanical strength during BDE-209 degradation to maintain their shape in the system at a stirring rate of 200-rpm, while undergoing continuous 365 nm UVA irradiation. This novel TiO2-Yi-Li immobilized chitosan beads system allowed a successful simultaneous integration of photolysis, photocatalysis and biodegradation to remove BDE-209. The remaining percentag...

Research paper thumbnail of 化學傳輸行為對土壤微生物分解多環芳香烴化合物之影響; Fates impact on PAH biodegradation in the soil/water system with surfactants

Research paper thumbnail of Effects of Malachite Green on the Microbiomes of Milkfish Culture Ponds

Water

Intensive fish farming through aquaculture is vulnerable to infectious diseases that can increase... more Intensive fish farming through aquaculture is vulnerable to infectious diseases that can increase fish mortality and damage the productivity of aquaculture farms. To prevent infectious diseases, malachite green (MG) has been applied as a veterinary drug for various microbial infections in aquaculture settings worldwide. However, little is known regarding the consequences of MG and MG-degrading bacteria (MGDB) on microbial communities in milkfish culture ponds (MCPs). In this study, small MCPs were used as a model system to determine the effects of MG on the microbial communities in MCPs. The addition of MG led to cyanobacterial blooms in the small MCP. The addition of MGDB could not completely reverse the effects of MG on microbial communities. Cyanobacterial blooms were not prevented. Microbial communities analyzed by next generation sequencing revealed that cyanobacterial blooms may be due to increase of nitrogen cycle (including nitrogen fixation, nitrate reduction and anammox) a...

Research paper thumbnail of Aerobic biodegradation of benzophenone-type UV-filter by bacterial strains isolated from WWTP sludge

Research paper thumbnail of A coupled UV photolysis-biodegradation process for the treatment of decabrominated diphenyl ethers in an aerobic novel bioslurry reactor

Environmental Science and Pollution Research

The commercial flame retardant is an emerging contaminant (EC) commonly found in soils and sedime... more The commercial flame retardant is an emerging contaminant (EC) commonly found in soils and sediments. A coupled UVphotolysis-biodegradation process was used to decompose decabromodiphenyl ether (BDE-209) in clay slurries. A novel bioslurry bioreactor (NBB) was employed in which BDE-209 degradation was maximized by the simultaneous application of LED UVA irradiation and biodegradation by a mixed bacterial culture. The rate of BDE-209 degradation decreased in the order: coupled UV photolysis-biodegradation (1.31 × 10-2 day-1) > UV photolysis alone (1.10 × 10-2 day-1) > biodegradation alone (1.00 × 10-2 day-1). Degradation intermediates detected included hydroxylated polybrominated diphenylethers, partially debrominated PBDE congeners and polybrominated dibenzofuran. The UV-resistant bacterial strains isolated that could utilize BDE-209 as a sole carbon source included Stenotrophomonas sp., Pseudomonas sp., and Microbacterium sp. These strains encoded important functional genes such as dioxygenase and reductive dehalogenases. Continuous UV irradiation during the NBB process affected various biochemical oxidative reactions during PBDEs biodegradation. Simultaneous photolysis and biodegradation in the NBB system described reduces operational time, energy, expense, and maintenance-demands required for the remediation of BDE-209 when compared to sequential UV-biodegradation process or to biodegradation alone. Keywords Coupled UV photolysis-biodegradation. Decabromodiphenyl ether. Novel bioslurry bioreactor. UV-resistant bacterial strains. Polybrominated dibenzofuran Highlights • A time, energy, and cost-saving technique using a coupled UV photolysis-biodegradation process for degrading BDE-209 in a novel bioslurry bioreactor. • Identification of isolated UV-resistant bacterial strains that potentially are able to utilize PBDEs as sole carbon source and the analysis of related functional genes. • The prediction of a possible pathway for BDE-209 degradation by coupled photolysis-biodegradation.

Research paper thumbnail of An Investigation of Airborne Bioaerosols and Endotoxins Present in Indoor Traditional Wet Markets before and after Operation in Taiwan: A Case Study

International Journal of Environmental Research and Public Health

Customers in Taiwan prefer to purchase fresh foods and household supplies at indoor traditional w... more Customers in Taiwan prefer to purchase fresh foods and household supplies at indoor traditional wet markets (TWMs). The health risk to indoor TWM staff exposed to bioaerosols needs to be evaluated, since these workers spend long periods of time in the market for stall preparation, selling, and stall cleaning. This study investigated the bioaerosols present in two indoor TWMs. The results showed that the cleaning process at Market A after operations, involving the use of an agitated waterspout, was able to decrease the concentration of bacterial bioaerosols (BBs) by an average of 64%, while at the same time increasing the concentration of fungal bioaerosols (FBs) by about 2.4 fold. The chemical sanitization process at Market B after operations was able to bring about average decreases of 30.8% in BBs and 19.2% in FBs, but the endotoxin concentration increased. Hotspots were found to be associated with vendors of fresh, live poultry and fresh, raw meat/seafood. Pseudomonas spp. and Cl...

Research paper thumbnail of Characterization of a Sequential UV Photolysis-Biodegradation Process for Treatment of Decabrominated Diphenyl Ethers in Sorbent/Water Systems

Microorganisms

Decabrominated diphenyl ether (BDE-209) is a primary component of the brominated flame retardants... more Decabrominated diphenyl ether (BDE-209) is a primary component of the brominated flame retardants used in a variety of industrial and domestic applications. BDE-209 bioaccumulates in aquatic organisms and has been identified as an emerging contaminant that threatens human and ecosystem health. Sequential photolysis-microbial biodegradation processes were utilized here to treat BDE-209 in clay- or soil-water slurries. The removal efficiency of BDE-209 in the clay-water slurries was high; i.e., 96.5%, while that in the soil-water slurries was minimal. In the clay-water slurries the first order rate constants for the UV photolysis and biodegradation of BDE-209 were 0.017 1/day and 0.026 1/day, respectively. UV wavelength and intensity strongly influenced the BDE-209 photolysis and the subsequent biodegradation of photolytic products. Facultative chemotrophic bacteria, including Acidovorax spp., Pseudomonas spp., Novosphingobium spp. and Sphingomonas spp., were the dominant members of t...

Research paper thumbnail of Photosynthetic bacteria enhanced water quality and integrity of microbial community composition of integrated multitrophic aquaculture system of milkfish Chanos chanos coastal farming

Research paper thumbnail of Variation of Microbial Communities in Aquatic Sediments under Long-Term Exposure to Decabromodiphenyl Ether and UVA Irradiation

Sustainability

Abiotic components create different types of environmental stress on bacterial communities in aqu... more Abiotic components create different types of environmental stress on bacterial communities in aquatic ecosystems. In this study, the long-term exposure to various abiotic factors, namely a high-dose of the toxic chemical decabromodiphenyl ether (BDE-209), continuous UVA irradiation, and different types of sediment, were evaluated in order to assess their influence on the bacterial community. The dominant bacterial community in a single stress situation, i.e., exposure to BDE-209 include members of Comamonadaceae, members of Xanthomonadaceae, a Pseudomonas sp. and a Hydrogenophaga sp. Such bacteria are capable of biodegrading polybrominated diphenyl ethers (PBDEs). When multiple environmental stresses were present, Acidobacteria bacterium and a Terrimonas sp. were predominant, which equipped the population with multiple physiological characteristics that made it capable of both PBDE biodegradation and resistance to UVA irradiation. Methloversatilis sp. and Flavisolibacter sp. were id...

Research paper thumbnail of Effects of sulfamethoxazole and sulfamethoxazole-degrading bacteria on water quality and microbial communities in milkfish ponds

Research paper thumbnail of Investigation of a Farm-scale Multitrophic Recirculating Aquaculture System with the Addition of Rhodovulum sulfidophilum for Milkfish (Chanos chanos) Coastal Aquaculture

Sustainability

Globally, coastal aquaculture is growing due to the large demand for marine products. Specific im... more Globally, coastal aquaculture is growing due to the large demand for marine products. Specific impacts caused by coastal aquaculture on the environment include the discharge of culture farm effluents, stress on ground water (the absence of recycling), nutrient pollution, and diseases of cultured animals. Three methods, integrated multitrophic aquaculture (IMTA), recirculating aquaculture system (RAS), and beneficial bacteria for aquaculture, have been developed to solve these problems. In this study, the advantages of IMTA and RAS were integrated to develop a novel multitrophic recirculating aquaculture system (MRAS) to adapt to the farm-scale culturing of milkfish (Chanos chanos). The photosynthetic bacteria Rhodovulum sulfidophilum was added to enhance the performance of the farm-scale milkfish MRAS. This setting could promote growth of beneficial bacteria, such as the nitrogen cycle-associated microbial community and the anoxygenic phototrophic Acidobacteria community. The ammoni...

Research paper thumbnail of The effects of marine farm-scale sequentially integrated multi-trophic aquaculture systems on microbial community composition, prevalence of sulfonamide-resistant bacteria and sulfonamide resistance gene sul1

Science of The Total Environment

Research paper thumbnail of A Comparison of the Microbial Community and Functional Genes Present in Free-Living and Soil Particle-Attached Bacteria from an Aerobic Bioslurry Reactor Treating High-Molecular-Weight PAHs

Sustainability

High-molecular-weight (HMW) polycyclic aromatic hydrocarbons (PAHs) contaminate a wide range of e... more High-molecular-weight (HMW) polycyclic aromatic hydrocarbons (PAHs) contaminate a wide range of ecosystems, including soils, groundwater, rivers and harbor sediments. The effective removal of HMW PAHs is a difficult challenge if a rapid remediation time and low economic cost are required. Bioremediation provides a cheap and eco-friendly cleanup strategy for the removal of HMW PAHs. Previous studies have focused on removal efficiency during PAHs bioremediation. In such studies, only limited research has targeted the bacterial communities and functional genes present in such bioremediation systems, specifically those of free-living (aqueous) bacteria and soil particle-attached bacteria present. In this study, a high-level of HMW PAH (1992 mg/kg pyrene) was bioremediated in an aerobic bioslurry reactor (ABR) for 42 days. The results showed a pseudo first order constant rate for pyrene biodegradation of 0.0696 day−1. The microbial communities forming free-living bacteria and soil-attach...