Biomedical subjects

S Vinitnantharat

Publications and source records attributed to S Vinitnantharat.

5 recordsLinked to original sources

PubMed2003

Degradation of organic substances and reactive dye in an immobilized-cell sequencing batch reactor operation on simulated textile wastewater.

Textile wastewater generally consists of high organic substances and is strongly colored. Reactive dye has been used extensively in the textile industries. It is water soluble and difficult to remove by chemical coagulation. Removal of organic substances simultaneously with dye can be achieved by a biological process. This study aims to investigate the treatability of the organic substances and reactive dye in immobilized-cell sequencing batch reactors (SBR). Three different supporting medias namely activated carbon, steel slag and plastic were used. The performance of each reactor was compared with a conventional sequencing batch reactor. The simulated textile wastewater containing the reactive azo dye Procion Red H-E7B of a concentration of 40 mg/L and COD 300 mg/L, was fed into the reactors. The supporting media in the SBR system, it will enhance the capability of COD and dye operating of the SBRs consisted of 5 periods; Fill 1.5 h, React (anoxic:oxic) 20 (14:6) h, Settle 1.5 h, Draw 0.5 h and Idle 0.5 h. The results revealed that by adding removal. During a steady state of operation, the COD and dye concentrations of each period were investigated. In addition, the prolonged anoxic period brought about better decolorization efficiency.

Bioreactors↗

PubMed2001

Quantitative bioregeneration of granular activated carbon loaded with phenol and 2,4-dichlorophenol.

Lignite based granular activated carbon of 20x30 mesh size was used to investigate the extent of bioregeneration of phenol and 2,4-DCP in a batch system. The adsorption isotherm fits very well with the Freundlich isotherm and it is apparent that 2,4-DCP is more adsorbable than phenol. The degree of reversible adsorption for phenol and 2,4-DCP were 32.9 and 10.6 %, respectively. The low percentages of their reversibility meant that the adsorption phenomena of both phenol and 2,4-DCP were not fully physicosorption. The microorganisms can regenerate 31.4% (21.2 mg g(-1)) of GAC loaded with phenol and 14.3% (24.8 mg g(-1)) of GAC loaded with 2,4-DCP over a period of 7-10 days. The bioregeneration of phenols closely followed the first order kinetics with the rate constant of 0.046 day(-1) at initial phenol concentration of 100 mg l(-1) and biomass concentration of 20 mg l(-1) MLVSS. The rate constant was 0.021 day(-1) at initial 2,4-DCP concentration of 200 mg l(-1) and 200 mg l(-1) MLVSS. In addition, the increasing in initial concentration of biomass in the solution shortened the time required to reach the asymptotic limit on the bioregeneration but rendered little impact on the bioregeneration percentage.

Adsorption↗

PubMed2001

A modeling approach to bioregeneration of granular activated carbon loaded with phenol and 2,4-dichlorophenol.

A predictive isotherm model was developed to evaluate the extent of bioregeneration of granular activated carbon loaded with phenol and 2,4-dichlorophenol (2,4-DCP). Two basic substrates (116 mg/L of phenol and 100 g/L 2,4-DCP) as single solute were prepared. The mixture of them was provided to bisolute system for assessing the competitive adsorption. The effect of by-products, which were generated during biodegradation of substrate and measured as COD, on bioregeneration in the bisolute was investigated. Freundlich adsorption parameters (Kads and 1/n) of 2,4-DCP were obviously higher than those of phenol in both single and bisolute. By-products in the bulk solution brought an adverse effect on adsorption capacity of GAC in all cases. By taking into account the by-product effect on adsorption, the Freundlich isotherms were used to formulate a predictive model of bioregeneration. Simulated results showed good consistency of observed results. Practical relevant of the proposed model for assessing of bioregeneration in the wastewater treatment was discussed by applying model to the BAC-SBR in the steady-state operation.

Adsorption↗

PubMed1999

Fish vaccines.

Fish vaccines can be delivered the same way we immunize warm-blooded animals. Fish can be immunized by immersion in vaccine for a short period of time--30 seconds to 2 minutes. They can be immunized by injection, intramuscularly or intraperitoneally, and orally by mixing vaccines with feed either by top dressing or by incorporating into feed as an ingredient. Fish also respond to vaccine the same way as other animals do, but since fish are cold-blooded animals, the response to vaccine depends largely on the water temperature. In general, the higher the water temperature, the faster the immune response of fish to the vaccine. During the past 20 years fish vaccines have become an established, proven, and cost-effective method of controlling certain infectious diseases in aquaculture worldwide. Fish vaccines can significantly reduce specific disease-related losses resulting in a reduction of antibiotics use. The final result is the decrease of overall unit costs and more predictable production. Fish vaccines are advantageous over antibiotics because they are natural biological materials that leave no residue in the product or environment, and therefore will not induce a resistant strain of the disease organism. Fish vaccines are licensed by the federal government and closely regulated in the same manner as all other veterinary vaccines to ensure safety, potency, and efficacy. Even though commercial vaccines for aquaculture work really well in terms of protecting the fish against certain diseases, they should be used only as part of the overall fish health management program, because fish vaccines are not a cure-all. Animal husbandry is still the key to success in aquaculture.

Animals↗

PubMed1997

Comparison of whole-cell antigens of pressure- and formalin-killed Flexibacter columnaris from channel catfish (Ictalurus punctatus).

OBJECTIVE: To identify and compare immunodominant antigens in whole-cell lysates of pressure- and formalin-killed Flexibacter columnaris. ANIMALS: Sera from naturally infected and vaccinated channel catfish. PROCEDURES: Whole-cell lysates of pressure- and formalin-killed F columnaris were compared, and antigens were isolated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The antigens were identified by staining, western blotting, and specific monoclonal antibodies to glycoproteins. Western blotting was performed, using sera from channel catfish (Ictalurus punctatus) with naturally acquired F columnaris infection and sera from channel catfish vaccinated with an experimental prototype F columnaris vaccine. RESULTS: Whole-cell lysates of pressure and formalin-killed F columnaris shared 4 proteins: 100, 80, 66, and 60 kd. The 60-kd antigen was a glycoprotein. Western blotting, using sera from naturally infected channel catfish, revealed the same proteins for pressure- and formalin-killed F columnaris. Sera from vaccinated fish reacted only to pressure-killed lysate antigens. CONCLUSIONS: Pressure- and formalin-killed F columnaris whole-cell lysates share 100-, 80-, 66-, and 60-kd proteins and are recognized by antibodies from naturally infected catfish and those vaccinated with formalin-killed F columnaris. Formalin treatment modifies or inactivates the 60-kd protein antigens, rendering them unrecognizable to antibodies from channel catfish naturally infected with F columnaris, suggesting that formalin-killed F columnaris may not be suitable for use as a bacterin against columnaris disease.

Animals↗