• KSBB Journal
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• v.10 no.4
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• pp.441-448
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• 1995

Optimized fermentation medium and cultural conditions for the production or exopolysaccharide KS-1 with Bacillus polymyxa KS-1 was following as; 30g g1ucose, 2.59g yeast extract, $2.5g KH_2PO_4, 0.5g NaCl, 0.3g MgSO_4.7H_20, 0.1g CaC0_3 0.05g, FeSO_4.7H_2O, and 0.05g MnS0_4 . 4H_20in 1 liter distilled water. The exopolysaccharide production was influenced by the by the temperature and pH, the optimal conditions for the production of exopolysaccharide KS-1 seemed to be $30^{\circ}C$ and pH 7.0, respectively. About $10.3g/\ell$ of maximum exopolysaccharide was obtained al the initial pH 7.0, $30^{\circ}C$, 2vvm of aeration rate and 400 rpm of impeller speed in a jar fermentor.

• Journal of Microbiology and Biotechnology
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• v.21 no.5
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• pp.519-524
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• 2011

The correlation between alcoholic fermentation rate, measured as carbon dioxide ($CO_2$) evolution, and the rate of hydrogen sulfide ($H_2S$) formation during wine production was investigated. Both rates and the resulting concentration peaks in fermentor headspace $H_2S$ were directly impacted by yeast assimilable nitrogenous compounds in the grape juice. A series of model fermentations was conducted in temperature-controlled and stirred fermentors using a complex model juice with defined concentrations of ammonium ions and/or amino acids. The fermentation rate was measured indirectly by noting the weight loss of the fermentor; $H_2S$ was quantitatively trapped in realtime using a pre-calibrated $H_2S$ detection tube which was inserted into a fermentor gas relief port. Evolution rates for $CO_2$ and $H_2S$ as well as the relative ratios between them were calculated. These fermentations confirmed that total sulfide formation was strongly yeast strain-dependent, and high concentrations of yeast assimilable nitrogen did not necessarily protect against elevated $H_2S$ formation. High initial concentrations of ammonium ions via addition of diammonium phosphate (DAP) caused a higher evolution of $H_2S$ when compared with a non-supplemented but nondeficient juice. It was observed that the excess availability of a certain yeast assimilable amino acid, arginine, could result in a more sustained $CO_2$ production rate throughout the wine fermentation. The contribution of yeast assimilable amino acids from conventional commercial yeast foods to lowering of the $H_2S$ formation was marginal.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1381-1388
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• 2012

An in vitro experiment was conducted to examine the effects of defaunation (removal of protozoa) on ruminal fermentation characteristics, $CH_4$ production and degradation by rumen microbes when incubated with cereal grains (corn, wheat and rye). Sodium lauryl sulfate as a defaunation reagent was added into the culture solution at a concentration of 0.000375 g/ml, and incubated anaerobically for up to 12 h at $39^{\circ}C$. Following defaunation, live protozoa in the culture solution were rarely observed by microscopic examination. A difference in pH was found among grains regardless of defaunation at all incubation times (p<0.01 to 0.001). Defaunation significantly decreased pH at 12 h (p<0.05) when rumen fluid was incubated with grains. Ammonia-N concentration was increased by defaunation for all grains at 6 h (p<0.05) and 12 h (p<0.05) incubation times. Total VFA concentration was increased by defaunation at 6 h (p<0.05) and 12 h (p<0.01) for all grains. Meanwhile, defaunation decreased acetate and butyrate proportions at 6 h (p<0.05, p<0.01) and 12 h (p<0.01, p<0.001), but increased the propionate proportion at 3 h, 6 h and 12 h incubation (p<0.01 to 0.001) for all grains. Defaunation increased in vitro effective degradability of DM (p<0.05). Production of total gas and $CO_2$ was decreased by defaunation for all grains at 1 h (p<0.05, p<0.05) and then increased at 6 h (p<0.05, p<0.05) and 12 h (p<0.05, p<0.05). $CH_4$ production was higher from faunation than from defaunation at all incubation times (p<0.05).

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.53-56
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• 2000

Two-stage fed-batch culture was peformed to improve the volumetric productivity of erythritol. In the growth phase dissolved oxygen was maintained to 20% and the feed medium was automatically supplied to the fermenter by pH-stat mode. The cell yield was 0.76 g-cell/g-glucose. In two-stage fed-batch culture, 41% of total erythritol conversion yield with 187 g/L of erythritol concentration and 2.79 g/L-h of maximum erythritol Productivity were obtained when 400 g/L of glucose was directly added in the form of non-sterile powder at production phase. The erythritol productivity increased in parallel with cell mass. The metabolic shift in the biosynthetic pathway of erythritol was caused by dissolved oxygen concentration. The production of gluconic acid was observed when the dissolved oxygen in the medium was maintained over 40% during the production phase, whereas the dissolved oxygen concentration lower than 40% caused the production of citric acid. But the butyric acid was produced independently with dissolved oxygen concentration in the medium. The production of organic acids such as gluconic acid, citric acid, and butyric acid was decreased by addition of mineral salts.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.2
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• pp.111-117
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• 2008

A Bunsen reaction section is a primary stage of Sulfur-iodine thermochemical hydrogen production cycle. This section is important, because it decides the efficiency of next stages. In order to produce hydrogen very efficiently, the characteristics of Bunsen reaction were investigated via two experimental methods. The one is a phase separation of $H_2SO_4-HI-H_2O-I_2$ mixture system, and the other is a direct Bunsen reaction. The characteristics of each method were investigated and compared. As the result of this study, the amount of HI and $I_2$ in $H_2SO_4$ phase via Bunsen reaction was more decreased than that via $H_2SO_4-HI-H_2O-I_2$ mixture system with increasing $I_2$ concentration. However, the amount of $H_2SO_4$ in $HI_x$ phase via Bunsen reaction was remarkably increased with increasing $I_2$ concentration, while that via $H_2SO_4-HI-H_2O-I_2$ mixture system was decreased. On the other hand, the range of initial composition which is able to separate into two liquid phases without $I_2$ solidification was almost alike.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.2
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• pp.184-190
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• 2005

A new VFAs production process from sewage sludge using Fenton's oxidation was investigated. Optimum concentrations of $H_2O_\;and\;Fe^{2+}$ as well as optimum reaction temperature for VFAs production were studied. In the presence of $Fe^{2+}$ as catalyst, the VFAs formation rate increased about 4 times compared to $H_2O_2$ oxidation process without $Fe^{2+}$. Optimum concentrations of $H_2O_2$ and $Fe^{2+}$ were 0.62 M and 0.007 M, respectively. VFAs formation reaction proceeded rapidly within 1 min and VFAs formed degraded partly to acetic acid and $CO_2$, which exhibited series reaction characteristics. Based on the economic aspect, reaction temperature of $25^{\circ}C$ and 10 min of reaction time were thought to be proper reaction conditions. The effect of initial pH in the range of $3{\sim}6.3$ on the VFAs formation was not observed.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.91-91
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• 2019

Hibiscus syriacus L. is widely distributed throughout Eastern and Southern Asia and its root bark has been used as a traditional remedy. Recently, the extracts of H. syriacus L. exerts anti-cancerous, anti-microbial, and anti-inflammatory activities. However, the effect of anthocyanin-rich fraction of H. syriacus L. petals (PS) has not been studied under excessive oxidative stress. In this study, we evaluated the cellular protective effect of PS in HaCaT human skin keratinocytes under hydrogen peroxide ($H_2O_2$)-induced oxidative stress conditions. PS at below $400{\mu}g/ml$ did not show any cell death; however, over $800{\mu}g/ml$ of PS gradually increased cell death. PS at below $400{\mu}g/ml$ significantly inhibited $H_2O_2$-induced apoptosis in HaCaT cells concomitant with downregulation of Bax and upregulation of pro-PARP and p-Bcl-2. Additionally, PS remarkably reversed $H_2O_2$-induced excessive reactive oxygen species (ROS) production and apoptosis, and also significantly inhibited mitochondrial ROS production concomitant with suppression of $H_2O_2$-induced mitochondrial depolarization. $H_2O_2$-mediated ratio of Bax to Bcl-2, and caspase-3 activation were markedly abolished in the presence of PS. Moreover, the inhibition of HO-1 function using zinc protoporphyrin, an HO-1 inhibitor, significantly attenuated the cellular protective effects of PS against $H_2O_2$, indicating the significance of HO-1 in PS mediated cytoprotective effect, which was mediated by activating nuclear factor erythroid 2-related factor-2 (Nrf2). Taken together, our results suggest that cytoprotective effect of PS in HaCaT keratinocytes against oxidative stress-induced apoptosis is mediated by inhibiting cellular and mitochondrial ROS production, which is downregulated by activating Nrf2/HO-1 axis.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.6
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• pp.915-921
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• 2012

Artemisiae Asiaticae Herba (AAH) has been used to remedy of symptoms such as bleeding, dysmenorrhea, eczema and itchy skin in Oriental Medicine. In this study, we investigated the protective effect of AAH on allergic response. The effect of AAH was analyzed by ELISA and RT-PCR in RBL-2H3 cells. We investigated cell viability, ${\beta}$-hexosaminidase and histamine as markers of degranulation, production of IL-4 and TNF-${\alpha}$, and gene expression of HDC2, cytokines and $Fc{\varepsilon}RI$ ${\alpha}{\beta}{\gamma}$ subunit. We found that AAH suppressed ${\beta}$-hexosaminidase and histamine release, the production of IL-4 and TNF-${\alpha}$ in RBL-2H3 by the anti-DNP IgE plus DNP-HSA stimulation. AAH also significantly decreased cytokine mRNA expressions, such as IL-$1{\beta}$, IL-2, IL-3, IL-4, IL-5, IL-6, IL-12, IL-13, TNF-${\alpha}$, and GM-CSF, and increased cytokine mRNA expressions of IL-10 in RBL-2H3. In addition, AAH suppressed mRNA expression of $Fc{\varepsilon}RI$ ${\alpha}{\beta}{\gamma}$ subunit on cell surface. Our results indicate that AAH protects against allergic response and exerts an anti-inflammatory effect through the inhibition of degranulation and production of cytokines and expression of $Fc{\varepsilon}RI$ ${\alpha}{\beta}{\gamma}$ subunit.

• Microbiology and Biotechnology Letters
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• v.28 no.5
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• pp.264-269
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• 2000

This study is that of providing a fairly practical practival guide to the use of natural pigment in food industry. A strain isolated from marine resources was carried out the production of red pigment. The pigment showed UV absorption maxima at 520 and 550 nm. The color intensity in aqueous solution was fairly stable in the ranges of pH 5~8. The strain KS-97 produced a maximum yield of red pigment at$ 25^{\circ}C$ for 72 hrs with pH 7.0. The strain KS-97 was iden-tified a Bacillus sp. based on morphological and biochemical characterization such as a rod from, motility, spore for-mation, Gram positive and catalase production. The production of red pigment indicated that the strain Ks-97 utilized at thigh concentration of colloidal chitin as carbon sources obtained maximum yield of red pigment at $25^{\circ}C$ for 72 hrs. The highest production of red pigment was observed with cultivation in medium containing 20% colloi-dal chitin, 2.5g polypeptone, 2.5g yeast extract, 1.0g $KH_2$$PO_4$, 0.01g $MgSO_4$.$6H_2$O, 0.01g $ZnSO_4$, 0.01 g $MnSO_4$(per 1).

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.8
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• pp.1188-1192
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• 2003

Negative feedback on GH responses to GH-releasing hormone (GHRH) and GH-releasing peptides (GHRPs) has been reported and this action has been suggested to act through an increase in somatostatin. To determine whether the acute administration of porcine GH (pGH) inhibits GH responsiveness to GHRP-2 and GHRH in swine, swine were intravenously administered with pGH (5${\mu}g$/kg BW) or placebo followed 180 min later by a second intravenous administration of saline, GHRP-2 (30 ${\mu}g$/kg BW), GHRH (1${\mu}g$/kg BW) and a combination of GHRP-2 and GHRH. Plasma GH concentration was measured by radioimmunoassay. Administration of pGH caused a significant increase in GH area under curve and GH peak concentrations (p<0.001) over placebo-treated group. Plasma GH concentrations peaked at 15 min and returned to baseline level within 90 min. Pretreatment of pGH abolished (p<0.01) GH response to GHRH and attenuated (p<0.05) GH response to GHRP-2 and GHRH combined, without affecting GH response to GHRP-2. These results demonstrate that negative feedback action on GH releasing effect of GHRH occurs in swine, and that GHRP-2 has ability to interact in this action.