• Bulletin of the Korean Chemical Society
• /
• v.33 no.7
• /
• pp.2133-2139
• /
• 2012

A new system using $TiO_2$ (nano-sized, band-gap 3.14 eV)-impregnated spherical ZnS (micro-sized, band-gap 2.73 eV) nano/micro-composites (Ti 0.001, 0.005, 0.01, and 0.05 mol %/ZnS) was developed to enhance the production of hydrogen from methanol/water splitting. The ZnS particles in a spherical morphology with a diameter of about 2-4 mm which can absorb around 455 nm were prepared by hydrothermal method. This material was used as a photocatalyst with loading by nano-sized $TiO_2$ (20-30 nm) for hydrogen production. The evolution of $H_2$ from methanol/water (1:1) photo splitting over the $TiO_2$/ZnS composite in the liquid system was enhanced, compared with that over pure $TiO_2$ and ZnS. In particular, 1.2 mmol of $H_2$ gas was produced after 12 h when 0.005 mol % $TiO_2$/ZnS nano/micro-composite was used. On the basis of cyclic voltammeter (CV) and UV-visible spectrums results, the high photoactivity was attributed to the larger band gap and the lower LUMO in the $TiO_2$/ZnS composite, due to the decreased recombination between the excited electrons and holes.

• Microbiology and Biotechnology Letters
• /
• v.23 no.4
• /
• pp.405-410
• /
• 1995

In order to screen dextranase with high dextranolytic activity from microbial origins, dextranase producing fungal isolates were isolated from soil of the Taeion area. 197 strains with dextranolytic activities were isolated, out of which 3 strains with high dextranolytic activities were selected in the first screening. A strain (GR-98) with a best dextranolytic activity was selected in the second screening. The strain was identified to be similiar Aspergillus ustus by the morphological and cultural characteristics. The optimum culture temperature and initial pH for the dextranase production of the strain was 30$\circ$C and 7.0, respectively. The optimum culture medium was composed of 2% dextran, 0.3% KNO$_{3}$, 0.05% K$_{2}$HPO$_{4}$, 0.02% MgSO$_{4}$-7H$_{2}$O, 0.05% KC1, and 2.5 $\mu$g/ml pyridoxamine, and the enzyme production was maximum when the strain was subcultured at 30$\circ$C for 7 days.

• Asian-Australasian Journal of Animal Sciences
• /
• v.25 no.7
• /
• pp.1038-1044
• /
• 2012

In the present study, the impact of Salmonella Typhimurium on cell-mediated immunity (CMI) was investigated in 5 week-old immuno divergent broiler lines selected for the high and low response to phytohemagglutinin-P. The immune response was assessed in peripheral-blood mononuclear cells (PBMCs) induced with Salmonella Typhimurium at different time intervals (0 h, 0.5 h, 2 h, 4 h, 6 h, 12 h and 24 h). The differential mRNA expression patterns of IFN-${\gamma}$, IL-2 and iNOS were evaluated by quantitative real time PCR. In-vitro production of nitric oxide (NO) was also estimated in the culture supernatant and correlated with iNOS mRNA expression. Present study showed higher production of NO in the high cell-mediated line (HCMI) as compared to the low cell-mediated line (LCMI) upon stimulation with Salmonella Typhimurium. Correspondingly, higher mRNA expression of iNOS and IFN-${\gamma}$ were observed in high response birds (HCMI); but IL-2 was down regulated in this line compared to the low response birds (LCMI). Significantly (p<0.05) higher expression of iNOS, IFN-${\gamma}$ and higher production of NO in high line indicated that the selection for PHA-P response might be employed for increasing the immune competence against Salmonella Typhimurium in chicken flocks.

• The Korea Journal of Herbology
• /
• v.28 no.3
• /
• pp.107-113
• /
• 2013

Objective : The purpose of this study was to investigate the effect of fermented Artemisiae Argyi Folium(AAF) on some activities of human hepatoma cell, HepG2. Method : To investigate the effect of fermented Artemisiae Argyi Folium(AAF) activity on the human hepatoma cells, AAF extracts was fermented by Lactobacillus pentosus K34(AFL) and Sacchromyces cerevisiae STV89(AFS). And the effects of AFL or AFS on the activities of HepG2 cell, such as cell viability, nitric oxide(NO) production and reactive oxygen species(ROS) production, were tested. Result : Human Hepatoma Cells were incubated each for 3 hours and 24 hours. Human Hepatoma Cells treated with the extract was measured with MTT assay. Then AFL was found to be non-toxic at concentrations of 10 ug/mL(3h), 100 ug/mL(24h) or more. AFS was the same result at concentrations of more than 10 ug/mL. The extract increased ROS generation in Human Hepatoma Cells. AFL increased at concentrations of 100 ug/mL more (3h, also 10 ug/mL more) and 50 ug/mL(24h) and AFS increased both 50 ug/mL. In point of NO generation, AFL inhibited at concentrations of 10 ug/mL(3h) and 100 ug/mL(24h) more (3h, also 10 ug/mL more) and AFS also inhibited 50 ug/mL or more. Conclusion : AFL and AFS, obtained from Artemisiae Argyi Folium extracts by fermentation, reduced the NO production and increased ROS production in HepG2 cell, without cytotoxicity on HepG2 cell. The results suggested that AFL and AFS increased the immunological effects of Artemisiae Argyi Folium extracts.

• Korean Journal of Medicinal Crop Science
• /
• v.15 no.4
• /
• pp.246-250
• /
• 2007

Rhodiola sachalinensis A. Bor is a Chinese herb containing the natural compound salidroside, which has been known to possess medical properties such as enhancing bodies' ability to survive in adverse environments and extending human life. To improve a metabolite production from Rhodiola sachalinensis callus cultures, the concentrations of macro nutrients were investigated. To investigate the salidroside production in Rhodiola sachalinensis callus cultures, we analyzed salidroside content in each callus which was cultured in 30 $m{\ell}$ of $2\;{\times}\;B_5$ liquid medium for 4 weeks. The optimal concentrations of macro nutrients for salidroside production ($67.96\;{\pm}\;3.41\;mg/{\ell}$) were found to be 99 mM $KNO_3$, 1 mM $(NH_4)_2SO_4$, 2 mM $NaH_2PO_4{\cdot}2H_2O$, 2 mM $CaCl_2{\cdot}2H_2O$ and 1 mM $MgSO_4{\cdot}7H_2O$. From these results, we determined the more upgraded culture condition for industrial production of salidroside.

• Asian-Australasian Journal of Animal Sciences
• /
• v.5 no.3
• /
• pp.559-561
• /
• 1992

Three strains each of L. bulgaricus and S. thermophilus isolated from indigenous dahi were examined for their rate of acid production and corresponding pH values in skim milk medium incubated at $40^{\circ}C$. No significant increase in titrable acidity or decrease in pH were recorded from initial period up to 2nd hour in both the strains. Following this period, however, there was a continuous increase in titrable acidity and a decrease in pH value in the milk for all the tested strains. Further it was observed that there was a variation among these strains for their acid production rate. High rate of acid production was recorded for the L. bulgaricus as compared to S. thermophilus. The results further, suggested that efforts should be made to select a proper pair of L. bulgaricus and S. thermophilus according to their rate of acid production, at a particular temperature in order to produce a good quality product.

• YAKHAK HOEJI
• /
• v.36 no.4
• /
• pp.390-396
• /
• 1992

Streptomyces minoensis DMCJ-144 isolated from soil produces the ${\alpha}-amylase$ inhibitor. Optimum culture conditions for ${\alpha}-amylase$ inhibitor production of the strain were determined in this experiment. The optimum composition of the culture medium was studied by supplementing various carbon sources, nitrogen sources, vitamins, and metal salts to the basal medium containing 1% glucose, 0.1% asparagine, 0.005% $MgSO_4{\cdot}7H_2O$, 0.005% $K_2HPO_4$, 0.005% NaCl. Other culture conditions such as the culture temperature, initial pH of the medium, aeration, and culture time were also investigated. When the strain was cultured in a 100 ml flask containing 20 ml of 2% glucose, 0.5% beef extract, 0.0002% riboflavin, 0.0002% thiamine HCI, 0.01% $ZnCl_2$, 0.005% $MgSO_4{\cdot}7H_2O$, 0.005% $CuSO_4{\cdot}5H_2O$, 0.005% NaCl, pH 7.2, 180 rpm at $30^{\circ}C$, the maximum production of the ${\alpha}-amylase$ inhibitor was observed after 5 days of the cultivation.

• Journal of Life Science
• /
• v.12 no.5
• /
• pp.570-576
• /
• 2002

The extremely halophilic archaebacterium Haloarcular sp. EH-1 was isolated from solar salts. Amylae production from Halonrcular sp. EH-1 have been studied. The results obtained were as follows. The optimal medium composition for the production of amylase from Haloarcular sp. EH-1 were soluble starch 1.5%, yeast extract 1.0%, MgSO$_4$ 7h$_2$O 2.0%, KCI 0.1%, NaCl 25% (pH 7.5). The incubation temperature, aeration rate and agitation speed were 4$0^{\circ}C$, 100 $m\ell$ medium / 500 $m\ell$ shaking flask, and 110 rpm. The cell growth and enzymatic activity was highest at 9 days of incubation. So amylase production appeared to be a growth-related phenomenon.

• Journal of Plant Biotechnology
• /
• v.4 no.1
• /
• pp.23-27
• /
• 2002

To establish an in vitro mass production system of grape anthocyanin pigments through callus and cell suspension culture, the effects of nitrogen source and sucrose on fresh weight and anthocyanin production in cell suspension culture of 'Sheridan' grape level were studied. When the medium was devoid of $NO_3^-$, cell fresh weight was either remained stable (1% sucrose) or slightly decreased with culture time (2,3, and 4% sucrose). When $NH_4^-$ was lacking, 3% sucrose was most favorable for cell growth. When $NH_4^-$ was supplied as N source, the anthocyanin content of 2% sucrose containing medium was maintained 2 times higher than other levels till day 8 in culture, then that of 3 and 4% sucrose which peaked at day 12 thereafter. The anthocyanin content was low than $NO_3^-$-free media. Total anthocyanin content in $NH_4^-$-free medium was just about a half of that of $NH_4^+$ medium. Anthocyanin production of 2% sucrose in $NH_4^+$ medium was maintained about 3-fold till day 8, then decreased thereafter. In $NH_4^+$ medium, pH decreased gradually with final pH of 3.5 to 4.0, while pH in $NH_4^+$-free medium increased with final pH of 6.5 to 7.5.

• Transactions of the Korean hydrogen and new energy society
• /
• v.19 no.2
• /
• pp.145-155
• /
• 2008

This paper deals with an economic evaluation of hydrogen production by fermentation. We evaluate the economic feasibility of domestic hydrogen production by fermentation utilizing glucose and waste water sludge in terms of hydrogen production prices. In addition, we make some sensitivity analysis of hydrogen prices by changing the values of input factors such as the price of glucose, the capital cost of the hydrogen production system, and the hydrogen production yields. The estimated hydrogen prices of the two-step dark-light hydrogen production by fermentation utilizing glucose was $5,347won/kgH_2$, and the single-step hydrogen production by anaerobic fermentation utilizing waste water sludge was $4,255won/kgH_2$, respectively. It is expected that the hydrogen production price by anaerobic fermentation can be reduced if we produce methane or hydrogen utilizing by-products such as alcohols and organic acids, or the government imposes some legal regulations on the treatment of waste water sludge.