• The Korean Journal of Pharmacology
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• v.25 no.1
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• pp.75-85
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• 1989

In opsonized zymosan activated PMN leukocytes, N-ethylamleiamide and $Hg^{++}$, penetrable sulfhydryl group inhibitors, inhibited superoxide generation, NADPH oxidase activity and lysosomal enzyme (lactic dehydrogenase and ${\beta}-glucuronidase$) secretion. P-Chloromercuribenzoic acid and p-chloromercuribenzenesulfonic acid, surface sulfhydryl group inhibitors did not affect superoxide generation but effectively inhibited both NADPH oxidase activity and lysosomal enzyme secretion. During phagocytosis, contents of surface and soluble sulfhydryl groups were gradually decreased with increasing incubation times. N-ethylmaleiamide and $Hg^{++}$ caused a loss of both surface and soluble sulfhydryl groups. P-Chloromercuribenzoic acid and p-chloromercuribenzenesulfonic acid significantly decreased the surface sulfhydryl content but did not after soluble sulfhydryl groups. Cysteine and mercaptopropionylglycine inhibited superoxide generation and lysosomal enzyme secretion. Glutathione had no effect on superoxide generation but remarkably inhibited lactic dehydrogenase release. Suppression of superoxide generation by N-ethylmaleiamide was reversed by cysteine and mercaptopropionyl-glycine but not by glutathione. Inactivation of NADPH oxidase by N-ethylmaleiamide was prevented by glutathione, cysteine or mercaptopropionylglycine. Stimulated superoxide generaion by carbachol was completely abolished by N-ethylrnaleiamide and antagonized by atropine. Thus, the expression of PMN leukocyte response to external stimuli may be associated with the change of sulfhydryl groups content. It is suggested that lysosomal enzyme secretion is influenced by both surface and soluble sulfhydryl groups, whereas superoxide generation by intracellular soluble sulfhydryl groups.

• The Korean Journal of Food And Nutrition
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• v.33 no.1
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• pp.17-26
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• 2020

This study was conducted to evaluate the functionality of fermented black garlic extracts under various conditions. Black garlic powder was prepared by aging for 0~72 hours at 80℃ depending on relative humidity (RH). It showed the highest antioxidant effects among the samples; the total antioxidant activity of black garlic powders at RH 75%, 84%, and 90% for 72 hours was increased 31.9 times, 28.2 times, and 22.6 times compared with that of the fresh garlic powder, respectively. Also, the alliin content was gradually decreased. S-ally-L-cysteine and S-ethyl-cysteine levels were increased; the highest values were 495.9 ㎍/g and 1,769.7 ㎍/g after aging for 72 hours at RH 75%. Aspartate transaminase (AST) and alanine transaminase (ALT) levels were increased following high fat diet feeding, but the rise was obviously reduced by administration of black garlic extract. The total cholesterol, LDL/VLDL-cholesterol, and triglyceride contents in serum were significantly lower in methionine and choline deficient (MCD) diet treatment groups than in the positive control group. The concentration was increased following the intake of black garlic and fermented black garlic extracts. Therefore, black garlic extracts could be an ideal material as a dietary supplement in healthy functional foods to improve the effects on fatty liver.

• BMB Reports
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• v.48 no.11
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• pp.636-641
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• 2015

There are controversial findings regarding the roles of nuclear factor (erythroid-derived 2)-like 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway on bone metabolism under oxidative stress. We investigated how Nrf2/HO-1 pathway affects osteoblast differentiation of MC3T3-E1 cells in response to hydrogen peroxide (H₂O₂), N-acetyl cysteine (NAC), or both. Exposing the cells to H₂O₂ decreased the alkaline phosphatase activity, calcium accumulation, and expression of osteoblast markers, such as osteocalcin and runt-related transcription factor-2. In contrast, H₂O₂ treatment increased the expression of Nrf2 and HO-1 in the cells. Treatment with hemin, a chemical HO-1 inducer, mimicked the inhibitory effect of H₂O₂ on osteoblast differentiation by increasing the HO-1 expression and decreasing the osteogenic marker genes. Pretreatment with NAC restored all changes induced by H₂O₂ to near normal levels in the cells. Collectively, our findings suggest that H₂O₂-mediated activation of Nrf2/HO-1 pathway negatively regulates the osteoblast differentiation, which is inhibited by NAC.

• KSBB Journal
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• v.23 no.6
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• pp.519-524
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• 2008

Monacolin-K is a strong anti-hypercholesterolemic agent produced by Monascus sp. via polyketide pathway. High-yielding mutants of monacolin-K were developed through rational screening strategies adopted based on understanding of monacolin-K biosynthetic pathway. Through the experiments for investigating various amino acids as putative precursors for the monacolin-K biosynthesis, it was found that production level of monacolin-K was remarkably increased when optimum amount of cysteine was supplemented into the production medium. We suggested that these phenomena might be related to the special roles of SAM (S-adenosyl methionine), a putative methyl group donor in the biosynthetic pathway of monacolin-K, demonstrating close interrelationship between SAM-synthesizing primary metabolism and monacolin-K synthesizing secondary metabolism. Namely, increase in the intracellular amount of SAM derived from the putative precursor, cysteine which was extracellularly supplemented into the production medium might contribute to the significant enhancement in the monacolin-K biosynthetic capability of the highly mutated producers. On the basis of these assumptions derived from the above fermentation results, we decided to construct efficient expression vectors harboring SAM synthetase gene (metK) cloned from A. nidulans, with the hope that increased intracellular level of SAM could lead to further enhancement in the monacolin-K production through overcoming a rate-limiting step associated with monacolin-K biosynthesis. Hence, in order to overcome the plausible rate-limiting step associated with monacolin-K biosynthesis by increasing intracellular level of SAM, we transformed the producer mutants with an efficient expression vector harboring gpdA promoter of the producer microorganism, and metK gene. Notably, from the resulting various transformants, we were able to screen a very high-yielding transformant which showed approximately 3.3 fold higher monacolin-K productivity than the parallel nontransformed mutants in shake flask cultures performed under the identical fermentation conditions.

• The Journal of Korean Medicine
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• v.37 no.2
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• pp.76-84
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• 2016

Objectives: We evaluated the anti-fatigue effects of Rh2-enriched Korean ginseng (Ginseng Rh2+) using a forced exercise-induced chronic fatigue mouse model. Methods: ICR male mice were subjected to running wheel for 1 h, 5 days/week during 4 weeks, and running velocity was gradually increased. Each running session was followed by oral administration of distilled water, Ginseng Rh2+ (150 or 300 mg/kg), or N-acetyl-L-cysteine (NAC, 100 mg/kg) 1 h later. The exercise tolerance and forced swimming test were performed to evaluate the fatigue condition. Results: Chronic forced exercise reduced the physical activity, as evidenced by the behavioral tests, which were notably ameliorated by Ginseng Rh2+ treatment. Ginseng Rh2+ treatment also attenuated the alterations of energy metabolism and oxidative stress in skeletal muscle tissues and/or sera, including malondialdehyde (MDA), lactate concentration and its related factors (lactate dehydrogenase, blood urea nitrogen, and glucose levels). Conclusion: These findings strongly suggest that Ginseng Rh2+ exerts a potent anti-fatigue effect through modulation of energy metabolism and oxidative response.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.1
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• pp.106-115
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• 2018

Objective: The goal of this study was to investigate the effects of dietary standard ileal digestible (SID) valine:lysine ratios on performance, intestinal morphology, amino acids of liver and muscle, plasma indices and mRNA expression of branched-chain amino acid (BCAA) metabolism enzymes. Methods: A total of 144 crossbred pigs (Duroc${\times}$Landrace${\times}$Large White) weaned at $28{\pm}4days$ of age ($8.79{\pm}0.02kg$ body weight) were randomly allotted to 1 of 4 diets formulated to provide SID valine:lysine ratios of 50%, 60%, 70%, or 80%. Each diet was fed to 6 pens of pigs with 6 pigs per pen (3 gilts and 3 barrows) for 28 days. Results: Average daily gain increased quadratically (p<0.05), the villous height of the duodenum, jejunum and ileum increased linearly (p<0.05) as the SID valine:lysine ratio increased. The concentrations of plasma ${\alpha}-keto$ isovaleric and valine increased linearly (p<0.05), plasma aspartate, asparagine and cysteine decreased (p<0.05) as the SID valine:lysine ratio increased. An increase in SID lysine:valine levels increased mRNA expression levels of mitochondrial BCAA transaminase and branched-chain ${\alpha}-keto$ acid dehydrogenase in the longissimus dorsi muscle (p<0.05). Conclusion: Using a quadratic model, a SID valine:lysine ratio of 68% was shown to maximize the growth of weaned pigs which is slightly higher than the level recommended by the National Research Council.

• Korean Journal of Microbiology
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• v.12 no.1
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• pp.37-51
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• 1974

Three strains which accumulated large quantities of L-hlutamic acid as the chief product of metabolism in the presence of glucose and inorhanic ammonium salt under the aerobic condition sere newly isolated. These strains have the general characters as follows: Gram-positive, short fod-shaped, non-sporulating, non-motile, and facultative anaerobe. A change of cell shates was not almost observed in their life cycles and neither a phenomenon of cell-elongation nor a pleomorphism was recognized in any cases. Together with rigid stability in Gram-stain, these characters as above indicated evidences that newly isolates would belong to genus Brevibacterium clearly differentiated from genus Corynebacterium. At the same time the newly isolates, in addition to nutritional requirement of biotin and thiamine, showed the distinctive character of requirement of special amino acid such as histidine or cysteine for their considerable growth. These physiological characters including nitrates reduction, reaction on milk, and slow formation of acid from sugar also were useful in confirming that these bacteria would be Brevibacterium ammoniagenes.

• IMMUNE NETWORK
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• v.5 no.4
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• pp.199-204
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• 2005

Background: ADP-ribosyl pyrophosphatases (ADPRase) has been known to catalyze the hydrolysis of ADP-ribose to ribose-5-phosphate and AMP. The role of ADPRase has been suggested to sanitize the cell by removing potentially toxic ADP-ribose. In this study, we examined the effect of nitric oxide on ADPRase activity in macrophages. Methods: ADPRase activity was measured in NO-inducing J774 cells. For in vitro experiments, recombinant human ADPRase was prepared in bacteria. Results: ADPRase activity was increased by the treatment of exogenous NO generating reagent, sodium nitroprusside (SNP), in J774 cells. The increased ADPRase activity was mediated by the post-translational modification, likely to cause cADP-ribosylation via nitrosylation of cysteine residue on the enzyme. The stimulation with endogeneous NO inducers, $TNF-{\alpha}/IFN-{\gamma}$, also increased ADPRase activity through NO synthesis. Futhermore, ADPRase activity may be mediated by the post-translational modification of ADPRase, ADP-ribosylation. Conclusion: These results indicate that NO synthesized by macrophage activation plays a critical role in the increase in ADPRase activity following ADP-ribose metabolism.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.2
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• pp.296-304
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• 2009

The nutritional significance of essential amino acids, as well as non-essential amino acids, is well documented in poultry production with regards to growth performance and protein accretion. However, the function of amino acids in the stress response is still unclear. L-Pipecolic acid, a L-lysine metabolite in the brain, induced a hypnotic and sedative effect acting via the ${\gamma}$- aminobutyric acid receptors. L-Arginine also induced a sedative effect via its metabolism to L-ornithine. In addition, three-carbon nonessential amino acids like L-alanine, L-serine and L-cysteine also induced sedative effects. These facts suggest that the requirement for amino acids in both essential and non-essential types may require reconsideration to add the concept of stress amelioration in the future.

• Journal of the Korean Chemical Society
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• v.5 no.1
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• pp.15-17
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• 1961

A ninhydrin positive substance(formed during germination of Mung Bean) which on a 2-dimensional chromatography(BuOH-HAc, and$ PhOH-NH_2$ gave a spot above glutamic acid was isolated by cutting out the appropriate spot on the paper and extracting the paper with water. Hydrolysis of this substance with $2N H_2SO_4\;or\;3N\;HCl\;at\;120^{\circ}C$ for 15 hours gave the spot of mainly glutamic acid, alanine and very faint of glycine and cysteine on a paper chromatography. It is suggested that the reaction of ${\gamma}$-glutamyl-cysteinecyl-glycine + L-alanine in the presence of ${\gamma}$-glutamyle transferase ${\rightarrow}$ ${\gamma}$-glutamyl-alanine + cysteinyl-glycine, takes place in germinated Mung Bean.