• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.593-603
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• 1999

Poly(3-hydroxybutyrate) (PHB) production by fermentation was examined under both restricted- and ample-oxygen supply conditions in a single fed-batch fermentation. Recombinant Escherichia coli transformed with the PHB production plasmid pSYLl07 was grown to reach high cell density (227 g/l dry cell weight) with a high PHB content (78％ of dry cell weight), using a glucose-based minimal medium. A simple flux model containing 12 fluxes was developed and applied to the fermentation data. A superior closure (95％) of the carbon mass balance was achieved. When the data were put into use, the results demonstrated a surprisingly large excretion of formate and lactate. Even though periods of severe oxygen limitation coincided with rapid acetate and lactate excretion, PHB productivity and carbon utilization efficiency were not significantly impaired. These results are very positive in reducing oxygen demand in an industrial PHA fermentation without sacrificing its PHA productivity, thereby reducing overall production costs.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.731-734
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• 2001

An efficient fermentation strategy for the high level production of ultra-high-molecular weight poly(3-hdyroxybutyrate) (PHB) was developed. Although the cell and PHA concentrations obtained by flask cultures at different initial pH (6.0 or 6.9) were almost same level, the molecular mass of PHB produced were quite different along with the initial pH. When a recombinant Escherichia coli XL1-Blue harboring pJC2 containing the Alcaligenes latus PHB biosynthesis genes was cultivated in flask culture (pH 6.0), the PHB having a very high molecular weight of 22 MDa could be produced while only below 1 MDa at initial pH 6.9. The ultra-high-molecular weight PHB could be synthesized to high concentration of 89.8 g/L resulting in the PHB productivity of 2.07 g/L-h by simple fed-batch culture. In this study, we report that PHB having various molecular mass can be produced by employing metabolically engineered E. coli strains harboring the plasmids of different copy numbers containing the A. latus phbCAB genes.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.5
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• pp.675-682
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• 2013

One hundred and sixty Taiwan country chickens (d-old chicks) were randomly assigned into four groups with four replicates and equal sex. Basal diets were supplemented with 0, 0.5, 1 and 2% of Bazhen powder, a traditional Chinese herbal medicine complex. The study was conducted for 14 wks. Experimental results indicated that Bazhen supplement did not influence feed intake, body weight gain and feed:gain ratio. Compared with control group, the percentage of serum HDL (high-density lipoprotein) linearly increased (p<0.03) and that of VLDL+LDL (very low-density+low-density lipoprotein) linearly decreased (p<0.03) in Bazhen supplemented groups, that 2% Bazhen was significantly different with control group (p<0.05). Chickens fed diets containing 2% Bazhen displayed reduced (p<0.05) serum GOT (glutamic-oxaloacetic transaminase) levels. The IgG, ${\gamma}$-globulin levels and PHA (phytohemagglutinin) skin challenge results in 1% Bazhan supplemented group were higher (p<0.05) than in the control group, the SRBC (sheep red blood cell) and ND (newcastle disease) titers in Bazhen supplemented groups were linear higher (p<0.05) than in the control group. The liver catalase activity and the capacity of scavenging DPPH (${\alpha}$-${\alpha}$-diphenyl-${\beta}$-picrylhydrazyl) radical were linearly increased (p<0.03) in Bazhen supplemented groups, and the 1 and 2% groups were different from the control group (p<0.05). Liver TBARS (thiobarbituric acid-reactive substances) levels in all Bazhen supplemented groups and total glutathione level in the 2% group were reduced (p<0.05) compared to the control group and displayed a linear response (p<0.05). The TBA (thiobarbituric acid) and pH value of the breast muscle after 24 h post-mortem in the Bazhen supplemented groups was linear lower (p<0.05) than in the control group. Results from this study demonstrated that Bazhen supplement in chicken had several beneficial effects, including increased SRBC and ND titers, HDL and IgG, ${\gamma}$-globulin levels, PHA skin challenge result, decreased VLDL+LDL and GOT levels, and displayed antioxidation effects in serum and carcass meat parameters.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.1999-2006
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• 2016

Background: Acute promyelocytic leukemia (APML) is characterized by the reciprocal translocation t(15;17) (p22;p12) resulting in the PML-$RAR{\alpha}$ fusion gene. A dual diagnostic and follow up approach was applied including cytogenetic demonstration of the t(15;17) translocation and detection dg PML-$RAR{\alpha}$ chimeric transcripts by molecular means. Purpose: Conventional cytogenetics involving bone marrow is beset with high probability of poor metaphase index and was substituted with phytohemagglutinin (PHA)-induced peripheral blood culture based cytogenetic analysis as a diagnostic & follow up modality in APML patients of Kashmir (North India). Both qualitative (RT-PCR) and quantitative (Q-PCR) tests were simultaneously carried out to authenticte the modified cytogenetics. Materials and Method: Patient samples were subjected to the said techniques to establish their baseline as well as follow-up status. Results: Initial cytogenetics revealed 30 patients (81%) Positive for t(15;17) whereas 7 (19%) had either cryptic translocation or were negative for t(15;17). Two cases had chromosome 16q deletion and no hallmark translocation t(15;17). Q-PCR status for PML-$RAR{\alpha}$ was found to be positive for all patients. All the APML patients were reassessed at the end of consolidation phase and during maintenance phase of chemotherapy where 6 patients had molecular relapse, wherein 4 also demonstrated cytogenetic relapse. Conclusions: It was found that PHA-induced peripheral blood cytogenetics along with molecular analysis could prove a reliable modality in the diagnosis and assessment of follow up response of APML patients.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.6
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• pp.363-370
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• 2015

The production of polyhydroxyalkanoates (PHAs) using Sequencing Batch Reactor (SBR) was investigated. The experiments were performed in two fabricated SBRs (4 L) of different oxidation state. Synthetic wastewater was used as substrate, using C/N/P ratio of 42:10:1. SBR 1 and SBR 2 were operated in aerobic dynamic feeding (ADF) and anaerobic/oxic dynamic feeding (AODF) condition, respectively. ADF provide feast and famine in aerobic condition, while AODF in anaerobic/oxic condition. PHAs production was found high in AODF than AOF. Maximum PHAs content of 40.0% (w/w)of biomass were produced in AODF mode. Produced PHAs structural and thermal property were good.

• KSBB Journal
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• v.13 no.2
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• pp.187-194
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• 1998

For mass production of polyhydroxyalkanoates (PHA), high cell density cultures of Alcaligenes eutrophus by fed-batch culture under phosphate-limitation condition has been investigated. PHA accumulation by the regulation by the regulation of initial phosphate concentration could be automatically induced, and high density cell culture above 200 g/L also could be successfully produced. The production of Poly-$\beta$-hydroxybutyrate (PHB) and dry cell weight increased with increasing the initial phosphate concentration. When the initial concentrations of phosphate were in the ranges of 1.5~4.5 g-PO$_4$/L, PHB and dry cell weight obtained were 83~266 g/L and 61~216 g/L, respectively, and PHB productivity was in the ranges of 1.35~3.10 g/L.h. When a mixture of glucose and propionic acid is used as carbon sources, poly(3-hydroxybutyrate-co-poly-3-hydroxyvalerate), P(3HB-co-3HV), could be also successfully produced under phosphate limitation condition. When the mole ratio of propionic acid to glucose in the feeding solution is 0.22, a final dry cell weight of 150 g/L and a P(3-HB-co-3HV) of 90 g/L were produced. Morphological changes and size distribution of PHB granules synthesized in A. eutrophus under phosphate-limitation condition are determined by TEM during the course of fed-batch. Mean granule diameters of PHB produced are in the range of 0.36~0.39 $\mu$m, and mean cell size was elongated from 0.54~0.59 $\mu$m$\times$ 1.3~1.5 $\mu$m to 0.83~0.89 $\mu$m $\times$2.0~2.3 $\mu$m. Phosphate concentration in media did not affect size distribution of PHB granule and cell.

• Korean Chemical Engineering Research
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• v.54 no.5
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• pp.665-670
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• 2016

This study deals with the possible degradation of toluene and acetic acid when subjected to cell-free enzyme system from the toluene degrading bacteria Pseudomonas putida and acetic acid degrading bacteria Cupriavidus necator. P. putida produces toluene dioxygenase only under the existence of toluene in culture medium and toluene is degraded to cis-toluene dihydrodiol by this enzyme. C. necator produces acetyl coenzyme A synthetase-1 and converts acetic acid to acetyl CoA in order to synthesize ATP to need for growth or PHA which is biodegradable polymer. In case of toluene degradation, the experiment was conducted before and after production of toluene dioxygenase as this enzyme, produced by P. putida, is an inducible enzyme. Toluene was detected using gas chromatography (GC). Similar amount of toluene was found in control group and before production of toluene dioxygenase (experimental group 1). However, reduction in toluene was detected after the production of toluene dioxygenase (experimental group 2). Acetic acid was detected through application of gas chromatography-mass spectrometer (GC-MS). The results showed the acetic acid peak was not detected in the experimental group to apply cell-free enzyme system. These results show that the cell-free enzyme system obtained from P. putida and C. necator retained the ability to degrade toluene and acetic acid. However, P. putida needs to produce the inducible enzyme before preparation of the cell-free enzyme system.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2005.11a
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• pp.74-75
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• 2005

In order to evaluate dietary brown seaweed and vancomycin on the performance, layers(Isa brown) were fed on basal diet and diets containing 2.0% of brown seaweed or 10ppm vancomycin. Brown seaweed diet significantly increased(p<0.01) nitrogen balance in layer, while excretion of uric acid nitrogen and metabolizable energy utilization were not different among diets. Layer consumed more the brown seaweed diet(p<0.05). Egg production were significantly different by diets but reduced(p<0.0001) with the experimental period passed. Layer fed brown seaweed diet gave thicker shell eggs, higher Haugh unit and higher egg white CuZnSOD activity compared with those in basal diet. Also, Brown seaweed diet increased MnSOD activity in erythrocyte cytosol and peroxidase in plasma, but decreased peroxide level in plasma, and increased proliferation of PBMC stimulated with PHA-P The result indicated that brown seaweed 2.0% diet in layer improved egg quality and performance due to increased protein synthesis which were related to regulation of antioxidant system and immune cell function in blood.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.7
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• pp.867-872
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• 2010

A comprehensive study was undertaken to evaluate the effect of naked neck (Na) gene on immune competence, serum biochemical parameters and carcass quality traits in three genotypes (NaNa, Nana and nana) of the naked neck chicken under a tropical climate (Southern India). Sixty day-old chicks (20 from each genotype) were selected randomly and reared under similar environmental conditions up to eight weeks of age. The cell mediated immune (CMI) response to phytohaemoagglutinin-P (PHA-P) was significantly higher ($p{\lgq}0.01$) in NaNa and Nana genotypes compared to nana birds. The humoral response as measured by antibody titre to sheep red blood cells (SRBC) was also significantly higher in NaNa. The total cholesterol, LDL and VLDL cholesterol levels were significantly ($p{\leq}0.01$) lower whereas HDL cholesterol level was significantly higher in NaNa and Nana compared to nana genotype. The presence of Na allele significantly increased the live weight and dressing yield, and decreased the feather cover and abdominal fat. The naked neck genotypes (NaNa/Nana) performed better than the normal (nana) siblings for almost all the traits studied.

• Journal of Korean Society on Water Environment
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• v.23 no.3
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• pp.309-313
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• 2007

In Activated Sludge Model, COD fraction of primary settled municipal wastewater was a very important parameter. In this study, the COD fraction was determined using the oxygen utilization rate experiments. Readily biodegradable COD ($S_S$) fraction was observed about 29.7% of influent TCOD. $S_I$, $X_I$, and $X_S$ were analyzed to be 7.6%, 7.3%, and 55.4% of TCOD, respectively. The model used in this study was developed based on ASM3 and modified Bio-P module in order to simulate the existing BNR process. Parameter estimation results showed that $Y_{STO,O2}$, $Y_{STO,NO}$, $Y_{H,O2}$, $Y_{H,NO}$, $Y_{PO4}$, ${\mu}_H$, $b_H$, ${\mu}_A$, $q_{PHA}$, $q_{PP}$ and ${\mu}_{PAO}$ were 0.7, 0.64, 0.61, 0.48, 0.31, 3.9, 0.1, 1.35, 4.98, 1.8 and 0.59, respectively. Using the presented model and the estimated parameters, the simulation of the existing BNR process was successfully conducted.