• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.5
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• pp.337-340
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• 2001

A galactooligosaccharide(GalOS)-producing yeast, OE-20 was selected from forty seven strains of yeast growing in Korean traditional Meju (cooked soybean) and the yeast was tentatively identified as Kluyveromyces maxianus var lactis by its morphology and fermentation profile. A maximum yield of 25.1%(w/w) GalOS, which corresponds to 25.1 g of GalOS per liter, was obtained from the reaction of 100 g per liter of lactose solution at 3$0^{\circ}C$, pH 7.0 for 18 h with an intracellular crude $\beta$-galactosidase. Glucose and galactosidase were found to inhibit GalOS formation. The GalOS that were purified by active carbon and celite 545 column chromatography were supplemented in MRS media and a stimulated growth was observed of some intestinal bacteria. In particular the growth rate of Bifidobacterium infantis in the GalOS containing MRS broth increased up to 12.5% compared to that of the MRS-glucose broth during a 48h incubation period.

• Journal of Life Science
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• v.23 no.11
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• pp.1342-1350
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• 2013

We examined the effect of hydrogen sulfide ($H_2S$) in chemical hypoxia-induced injury in mouse hepatocytes. Cell viability was significantly decreased by cobalt chloride ($CoCl_2$), a well-known hypoxia mimetic agent in a time- and dose- dependent manner. Sodium hydrosulfide (NaHS, a donor of $H_2S$) pretreatment before exposure to $CoCl_2$ significantly attenuated the $CoCl_2$-induced decrease of cell viability. $CoCl_2$ treatment resulted in an increase of intracellular ROS generation, which is inhibited by NaHS or N-acetyl-cysteine (NAC, a ROS scavenger), and p38 MAPK phosphorylation, which is also blocked by NaHS or NAC. The $CoCl_2$-induced increase of the Bax/Bcl-2 ratio was attenuated by NaHS, NAC, and SB 203580 (p38 MAPK inhibitor). The $CoCl_2$-induced decrease of cell viability was also attenuated by NaHS, NAC, and SB 203580 pretreatment. Additionally, NaHS inhibited the $CoCl_2$-induced COX-2. Similar to the effect of NaHS, NAC blocked $CoCl_2$-induced COX-2 expression. Furthermore, NS-398 (a selective COX-2 inhibitor) attenuated not only the $CoCl_2$-induced increase of the Bax/Bcl-2 ratio, it also decreased cell viability. Taken together, $H_2S$ protects primary cultured mouse hepatocytes against $CoCl_2$-induced cell injury through inhibition of the ROS-activated p38 MAPK cascade and the COX-2 pathway.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.6196-6202
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• 2012

Oligo-alginate derivatives were extracted from brown algae and its antimicroalgal effects and reaction mechanism were investigated. Oligo-alginate derivatives were produced from sequential hydrolysis of high molecular weight alginate by treatment of 2 N HCl and 1% $H_2O_2$. Antimicroalgal activity of extracts was proportional to reaction time and activity was highest at 4 hrs. When oligo-alginate derivatives were treated to Akashiwo sanguinea and Cochlodinium polykrikoides, mobilities of cells were ceased. A. sanguinea cells were crushed and plasmolysis was induced in C. polykrikoides cells. To investigate the action mechanism of oligo-alginate derivatives, changes of intracellular (pHi) and extracellular pH (pHe) were determined in the microalgal cells exposed to 0.05% of oligo-alginate derivatives. pHi was decreased about 0.3 unit and pHe was increased about 0.9 unit. These results suggested that change of membrane potential by oligo-alginate derivatives could led to microalgal cell death.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.3
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• pp.149-156
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• 2011

Golgi SNAP receptor complex 1 (GS28) has been implicated in vesicular transport between intra-Golgi networks and between endoplasmic reticulum (ER) and Golgi. Additional role(s) of GS28 within cells have not been well characterized. We observed decreased expression of GS28 in rat ischemic hippocampus. In this study, we examined the role of GS28 and its molecular mechanisms in neuronal (SK-N-SH) cell death induced by hydrogen peroxide ($H_2O_2$). GS28 siRNA-transfected cells treated with $H_2O_2$ showed a significant increase in cytotoxicity under glutathione (GSH)-depleted conditions after pretreatment with buthionine sulfoximine, which corresponded to an increase of intracellular reactive oxygen species (ROS) in the cells. Pretreatment of GS28 siRNA-transfected cells with p38 chemical inhibitor significantly inhibited cytotoxicity; we also observed that p38 was activated in the cells by immunoblot analysis. We confirmed the role of p38 MAPK in cotransfected cells with GS28 siRNA and p38 siRNA in the cell viability assay, flow cytometry, and immunoblot. Involvement of apoptotic or autophagic processes in the cells was not shown in the cell viability, flow cytometry, and immunoblot analyses. However, pretreatment of the cells with necrostatin-1 completely inhibited $H_2O_2$-induced cytotoxicity, ROS generation, and p38 activation, indicating that the cell death is necroptotic. Collectively these data imply that $H_2O_2$ induces necroptotic cell death in the GS28 siRNA-transfected cells and that the necroptotic signals are mediated by sequential activations in RIP1/p38/ROS. Taken together, these results indicate that GS28 has a protective role in $H_2O_2$-induced necroptosis via inhibition of p38 MAPK in GSH-depleted neuronal cells.

• Archives of Pharmacal Research
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• v.27 no.4
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• pp.429-435
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• 2004

Ginseng has an anti-cancer effect in several cancer models. This study was to characterize active constituents of ginseng and their effects on proliferation of prostate cancer cell lines, LNCaP and PC3. Cell proliferation was measured by $[^3H]$thymidine incorporation, the intracellular calcium concentration by a dual-wavelength spectrophotometer system, effects on mite-gen-activated protein (MAP) kinases by Western blotting, and cell attachment and morphologic changes were observed under a microscope. Among 11 ginsenosides tested, ginsenosides $Rg_3\;and\;Rh_2$ inhibited the proliferation of prostate cancer cells. $EC_{50}s\;of\;Rg_3\;and\;Rh_2$ on PC3 cells were $8.4{\mu}M\;and\;5.5{\mu}M$, respectively, and $14.1{\mu}M\;and\;4.4{\mu}M$ on LNCaP cells, respectively. Both ginsenosides induced cell detachment and modulated three modules of MAP kinases activities differently in LNCaP and PC3 cells. These results suggest that ginsenosides $Rg_3\;and\;Rh_2$-induced cell detachment and inhibition of the proliferation of prostate cancer cells may be associated with modulation of three modules of MAP kinases.

• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.967-971
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• 2004

The kinetics of sulfite uptake were examined in a wild-type laboratory strain of Saccharomyces cerevisiae to determine if carrier-mediated sulfite uptake involved a proton symport, as previous studies on sulfite uptake have suggested both an active process and facilitated diffusion. Accumulation of intracellular sulfite was initially rapid and linear up to 50 sec. Uptake was saturable at final concentrations equal to or greater than 3 mM sulfite, and increased 2-fold in the presence of 2% glucose. Uptake was significantly reduced in cells pretreated with 100-500 $\mu$M carbonyl cyanide mchlorophenylhydrazone (CCCP) or 2,4-dinitrophenol (DNP), both of which dissipate proton gradients. Uptake was also significantly inhibited in the presence of 1 mM arsenate, an inhibitor of ATP synthesis. Extracellular alkalization was observed in cells incubated with 1-2 mM sulfite in a weak tartrate buffer at pH 3.5 and 4.5. These findings suggest that the bisulfite ion, $HSO_3^-$, an anionic form of sulfite, is taken up by a carrier-mediated proton symport. A met16 sull sul2 mutant, impaired in both sulfite formation and sulfate uptake, was found able to grow on a medium with sulfite as the sole Sulfur source, indicating that the sulfate transporters Sul1p and Sul2p are not required for sulfite uptake.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.764-768
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• 2008

Bovine testicular hyaluronidase PH-20 was cloned into pPIC9 vector and expressed in Pichia pastoris. Recombinant PH-20 was 75 kDa MW and 7460 units/L activity. Extracellular hyaluronidase activity was two times higher than that of intracellular activity. Non-buffered medium and $30^{\circ}C$ cultivation was favorable for PH-20 production. 1M sorbitol as an osmotic pressure and 0.3% methanol inducer increased cell growth and enzyme activity. 0.4 M arginine augmentation decreased the proteolytic degradation of recombinant hyaluronidase.

• BMB Reports
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• v.38 no.3
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• pp.343-349
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• 2005

Gamma-glutamyltransferase (GGT, EC 2.3.2.2) which hydrolyzes glutathione (GSH), is required for the maintenance of normal intracellular GSH concentration. GGT is a membrane enzyme present in leukocytes and platelets. Its activity has also been observed in human neutrophils. In this study, GGT was purified from Triton X-100 solubilized neutrophils and its kinetic parameters were determined. For kinetic analyses of transpeptidation reaction, $\gamma$-glutamyl p-nitroanilide was used as the substrate and glycylglycine as the acceptor. Apparent $K_m$ values were determined as 1.8 mM for $\gamma$-glutamyl p-nitroanilide and 16.9 mM for glycylglycine. The optimum pH of GGT activity was 8.2 and the optimum temperature was $37^{\circ}C$. It had thermal stability with 58% relative activity at $56^{\circ}C$ for 30 min incubation. L-serine, in the presence of borate, was detected as the competetive inhibitor. Bromcresol green inhibited neutrophil GGT activity as a noncompetetive inhibitor. The neutrophils seem to contain only the isoenzyme that is present in platelets. We characterized the kinetic properties and compared the type of the isoenzyme of neutrophil GGT with platelet GGT via polyacrylamide gel electrophoresis (PAGE) under a standart set of conditions.

• Food Science and Preservation
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• v.30 no.5
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• pp.797-810
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• 2023

Elaeagnus umbellata leaves have been reported to suppress inflammation, allergic responses, lung cancer proliferation and oral bacterial growth. Cadmium (Cd) is a heavy metal that has been found to cause many toxicities, including liver toxicity. The aim of this study was to evaluate the capacity of 70% ethanol extract of E. umbellata leaves (EUL) to protect human hepatocytes from Cd toxicity. After exposure of HepG2 cells to Cd at 10 𝜇M for 24 h, cell viability, expression levels of apoptosis- and antioxidant-related proteins, reactive oxygen species (ROS) accumulation and Cd uptake were assessed. EUL protected HepG2 cells from Cd-induced apoptosis as determined by MTT assay. A decrease in caspase-3 and p-p53 protein levels was observed in cells pretreated with EUL prior to Cd exposure. Furthermore, the Cd-induced increase in intracellular DCF fluorescence was attenuated by EUL, indicating that the Cd-induced apoptosis preventing effect was associated with the suppression of ROS accumulation. Moreover, EUL's effects on the inhibition of p38, JNK, and AKT phosphorylation also appear to be associated with protection against Cd toxicity. Moreover, EUL upregulated Cd-depressed expression of Nrf2, HO-1, catalase, and MT-1,2 proteins, suggesting that Cd uptake-induced apoptosis in HepG2 cells may be inhibited by EUL's antioxidative potential.

• Journal of Animal Science and Technology
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• v.45 no.5
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• pp.703-710
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• 2003

The purpose of this study was to detect association between genetic variation and economic trait in the porcine heart type fatty acid-binding protein gene as a candidate gene for the traits related with growth and meat quality in pigs. The H-FABP is a 15-kDa protein expressed in several tissues with high demand for fat metabolism such as cardiac and skeletal muscle and lactating mammary gland. H-FABP is small intracellular protein involved in fatty acid transport from the plasma membrane to the site of $\beta$-oxidation and/or triacylglycerol or phospholipid synthesis. In this study, H-FABP PCR-RFLP was performed in F$_2$ population composed of 214 individuals from an intercross between Korean Native Boars and Landrace sows. PCR products from two primer sets within H-FABP gene were amplified in 850bp and 700bp. Digestion of PCR products with the restriction digestion enzymes HaeⅢ and HinfⅠ, revealed fragment length polymorphisms(RFLPs). The genotype frequencies from H-FABP/HaeⅢ was .29 for genotype DD, .53 for genotype Dd, and .15 for genotype dd, respectively. The genotype frequencies of HH, Hh, and hh from H-FABP/HinfⅠ was .38, .41 and .20, respectively, in the population. Relationships between their genotypes and economic traits were estimated. In H-FABP/HaeⅢ locus, there were specific genotypes(Dd and dd) associated with economic traits such as body weights at 3, 5, 12, and 30 week of age (p〈.05 to .001). The ‘d’ allele was associated with gaining of body weight. In H-FABP/HinfⅠ locus, Genotypes of HH and Hh associated with growth traits such as body weights at 5, 12, and 30 week of age (p〈.05 or p〈.001) and back fat thickness, body fat including abdominal and trimmed fat (p〈.001) and intramuscular fat(p〈.05) The ‘H’ allele was positively associated with gaining of body weight and fatness deposition. In conclusion, a significant association of the H-FABP gene from its genetic variation was found on body weight, intramuscular fat and backfat thickness.