• Journal of Life Science
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• v.18 no.1
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• pp.9-15
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• 2008

Sulfur containing compounds in garlic have all be used as one of the traditional folk medicine as well as food source. The present study was performed to investigate the antioxidative compounds of 1-methyl-1-cysteine, dimethyl trisulfide and 2-vinyl-4H-1,3-dithiin. The antioxidative activity of sulfur containing compounds on human LDL was investigated by monitoring a thiobarbituric acid substances (TBARS). Sulfur containing compounds inhibited on oxidation of LDL mediated by $CuSO_4$ and macrophages in dose dependent manner with almost completely inhibition at $80{\mu}g/ml$. Antioxidant activities of sulfur containing compounds on LDL oxidation were 2-vinyl-4H-1,3-dithiin, 1-methyl-1-cysteine, and dimethyl trisulfide in order. Inhibitory effects of sulfur containing compounds on oxidation of LDL mediated by $CuSO_4$ and macrophages were degraded at much greater rate than native LDL, the LDL oxidation process was arrested as shown by the lower conjugated dienes formation at the concentration of $60{\mu}g/ml$. Sulfur containing compounds in garlic revealed at high antioxidative activity at low physiological concentration for human LDL oxidation in vitro specially, it was indicated that the antioxidative activity of 3-viny l-4H-1,2-dithiin was higher than that of the other sulfur containing compounds.

• Journal of Life Science
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• v.19 no.8
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• pp.1119-1124
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• 2009

Hyperlipidemia has been reported to be associated with the development of fatty liver. Palmitic acid, a major saturated fatty acid, is involved in the development of diverse diseases. The activation of mitogen activated protein kinases (MAPKs), such as Jun N-terminal kinase (INKs) and p38 MAPK is implicated in the apoptosis in diverse cells. Thus, this study was conducted to investigate the effects of palmitic acid on apoptosis and its relationship between JNK and p38 MAPK in cultured rat hepatocytes. In the present study, palmitic acid (>50 uM) decreased cell proliferation and increased lactate dehydrogenase activity in hepatocytes, which was blocked by the treatment of SP600125 (a JNK inhibitor) and SB203580 (a p38 MAPK inhibitor). Indeed, palmitic acid decreased Bcl-2 expression but increased Bax expression in rat hepatocytes, which was blocked by the treatment of SP600125 and SB203580. In addition, palmitic acid decreased glutathione (GSH) content and increased lipid peroxide formation, which was blocked by the treatment of SP600125 and SB203580. Western immunoblotting analysis also revealed that palmitic acid increased JNK and p38 MAPK. In conclusion, palmitic acid induced apoptosis through oxidative stress via JNK and p38 MAPK activation in rat hepatocytes.

• Journal of Life Science
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• v.23 no.10
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• pp.1288-1294
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• 2013

Knowledge of morphological changes in eel larvae is very important for artificial rearing of eel larvae. In this study, we investigated the morphological structure of the head region and histological changes of the eye retina in artificially reared larvae at various stages and in glass eel just after metamorphosis. Structural changes were observed in the upper jaw (maxilla) and the lower jaw (mandible) after 100 dah (day after hatchery) and after metamorphosis. Teeth had degenerated by the time of completion of metamorphosis. Major histological changes observed in the eye retina were the formation of the outer plexiform layer and the outer nuclear layer from 100 dah larva and a change in the rod cell layer after metamorphosis. The cornea was not observed at 10 dah in the eel larva. More information is needed on the early developmental stages of eel larvae to enable mass production of glass eels. The results obtained in the present research will be useful when developing novel rearing programs for eel larvae.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.422-427
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• 1994

The quality of salted and semi-dried mackerel prepared by cold osmotic dehydration using a high osmotic pressure resin during storage at $5{\pm}1^{\circ}C$ was evaluated. The moisture contents in salted and semi-dried mackerel decreased in. range of 4 during storage. The brown pigment formation content and peroxide value of salted and semi-dried mackerel prepared by osmotic dehydration were more lower than those of salted and semi-dried mackerel prepared by traditional drying methods such as sun-drying, hot-air drying and cold air drying. The viable cell count and histamine contents of cold osmotic dried products were much lower and revealed a tendency to increase during storage, but even these values after storage of 15 days showed that the salted and semi-dried mackerel was safety in respect of food sanitation. The ratio of saline soluble nitrogen to total nitrogen in cold osmotic dried products were higher than that of traditional dried products during storage. Judging from the results of chemical and sensory evaluation, shelf-life of salted and semi-dried mackerel by cold osmotic drying were more longer than that of salted and semi-dried mackerel prepared by traditional drying.

• Journal of Applied Biological Chemistry
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• v.61 no.3
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• pp.213-217
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• 2018

Tolaasin secreted by Pseudomonas tolaasii is a peptide toxin and causes brown blotch disease on the cultivated mushrooms by collapsing cellular and fruiting body structure. Toxicity of tolaasin was evaluated by measuring hemolytic activity because tolaasin molecules form membrane pores on the red blood cells and destroy cell membrane structure. In the previous studies, we found that tolaasin cytotoxicity was suppressed by $Zn^{2+}$ and $Ni^{2+}$. $Ni^{2+}$ inhibited the tolaasin-induced hemolysis in a dose-dependent manner and its $K_i$ value was 1.8 mM. The hemolytic activity was completely inhibited at the concentration higher than 10 mM. The inhibitory effect of $Zn^{2+}$ on tolaasin-induced hemolysis was increased in alkaline pH, while that of $Ni^{2+}$was not much dependent on pH. When the pH of buffer solution was increased from pH 7 to pH 9, the time for 50% hemolysis ($T_{50}$) was increased greatly by $100{\mu}M$ $Zn^{2+}$; however, it was slightly increased by 1 mM $Ni^{2+}$ at all pH values. When the synergistic effect of $Zn^{2+}$ and $Ni^{2+}$ on tolaasin-induced hemolysis was measured, it was not dependent on the pH of buffer solution. Molecular elucidation of the difference in pH-dependence of these two metal ions may contribute to understand the mechanism of tolaasin pore formation and cytotoxicity.

• Journal of Microbiology and Biotechnology
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• v.24 no.1
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• pp.26-35
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• 2014

Saccharothrix algeriensis NRRL B-24137 produces naturally different dithiolopyrrolone derivatives. The enzymatic activity of pyrrothine N-acyltransferase was determined to be responsible for the transfer of an acyl group from acyl-CoA to pyrrothine core. This activity was also reported to be responsible for the diversity of the dithiolopyrrolone derivatives. Based on this fact, nine dithiolopyrrolone derivatives were produced in vitro via the crude extract of Sa. algeriensis. Three of them have never been obtained before by natural fermentation: acetoacetyl-pyrrothine, hydroxybutyryl-pyrrothine, and dimethyl thiolutin (holomycin). Two acyltransferase activities, acetyltransferase and benzoyltransferase catalyzing the incorporation of linear and cyclic acyl groups to the pyrrothine core, respectively, were biochemically characterized in this crude extract. The first one is responsible for formation of acetyl-pyrrothine and the second for benzoyl-pyrrothine. Both enzymes were sensitive to temperature changes: For example, the loss of acetyltransferase and benzoyltransferase activity was 53% and 80% respectively after pre-incubation of crude extract for 60 min at $20^{\circ}C$. The two enzymes were more active in neutral and basal media (pH 7-10) than in the acidic one (pH 3-6). The optimum temperature and pH of acetyltransferase were $40^{\circ}C$ and 7, with a $K_m$ value of $7.9{\mu}M$ and a $V_{max}$ of $0.63{\mu}M/min$ when acetyl-CoA was used as limited substrate. Benzoyltransferase had a temperature and a pH optimum at $55^{\circ}C$and 9, a $K_m$ value of $14.7{\mu}M$, and a $V_{max}$ of $0.67{\mu}M/min$ when benzoyl-CoA was used as limited substrate.

• Restorative Dentistry and Endodontics
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• v.13 no.2
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• pp.283-294
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• 1988

The purpose of this study was to investigate the characteristic features of the cells and tissues of the chronic periapical lesions using light microscope and electron microscope. Fifteen dental periapical lesions were obtained from the patients undergoing periapical surgery. Each specimen was divided into two parts along the tooth axis. One part was routinely processed for histopathologic examinations. 12 periapical lesions were diagnosed as granuloma and 3 periapical specimens as periapical cyst. The other part was fixed in 2.5% glutaraldehyde in 0.1M sodium cacodylate buffer at pH 7.4 and 1% osmic acid in same buffer. They were embedded in Epon 812. The semithin sections were used for the orientation of the lesions and the ultrathin sections were stained conventionally and examined with AEI Corynth 500 electron microscope. The results were as follows. 1. PMN and macrophages, which were dominant cell type, were scattered in small or large numbers throughout the central destructive area of granuloma. In the granulomatous area, plasma cells and lymphoytes were found in significant number and a lot of new capillary formation were revealed. Clefts caused by cholesterol were often seen in the connective tissue. Occasionally foam cells became collected in groups and epithelial proliferation were present. 2. In both granuloma and cyst, some plasma cells contained narrow cisternae of granular endoplasmic reticulum of which was tightly packed with electron dense materials, and other cells exhibited dilated profiles of granular endoplasmic reticulum. 3. In the area where plasma cells and lymphocytes were collected in groups, lymphocytes with well developed nucleolus and profuse cytoplasm were found and differentiating plasma cells were also present. 4. In the epithelial strands of the granulomatous area, epithelial cells contained enlarged endoplasmic reticulum, tonofilaments and ribosoms. Toward the intercellular space epithelial cells protruded a few microvilli. In the intercellular space, exudate-like electron dense materials, most of which was attached to the plasma membrane, appeared. 5. Some foam cells filled with numerous lipid droplets and others had lipid droplets and crystal-like structures. 6. Cyst epithelium consisted of bright cells and dark cells. The former had bright cytoplasm and small amounts of ribosoms, and the latter dark cytoplasm, many ribosoms, mitochondria and elongated microvilli. 7. Epithelial cells near the cyst lumen protruded a lot of long microvilli toward intercellular space and cyst lumen.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.283-288
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• 1989

The effect of storage temperature on the quality characteristics of meat sausage was investigated. Thus, the quality characteristic changes of meat sausage were discussed through physico-chemical and microbiological analysis. The results were summarized as follows; Volatile basic nitrogen(VBN) was increased more rapidly at $40^{\circ}C$ than at $10^{\circ}C$, $20^{\circ}C$ and fluctuating temperature $(10/40^{\circ}C)$. In physico-chemical analysis of meat sausage, the values of VBN , viable cell counts were increased with increase of temperature during storage, while thiobarbituric acid(TBA) values were fluctuated during storage as a whole. Water activity(Aw) and moisture contents showed a little change according to storage temperature, but sausage color was darkened as storage time goes by as a whole, the shelf-life was predicted above 40 days at $10^{\circ}C$, below 40 days at $20^{\circ}C$, below 30 days at $40^{\circ}C$ and about 20 days fluctuating temperature $(10/40^{\circ}C)$, respectively on the basis of slime formation in sensory evaluation.

• Polymer(Korea)
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• v.37 no.5
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• pp.632-637
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• 2013

It has been widely accepted that costal cartilage cells (CCs) have more excellent initial proliferation capacity than articular cartilage cells as well as the easiness for isolation and collection. This study demonstrated that CCs might be one of the substitutes for articular cartilage cells by tissue engineered cartilage. Poly(lactic-co-glycolic acid) (PLGA) has been extensively tested and used as scaffold material but it was limited by the low attachment of cells and the induction of inflammatory cells. Base on previous our studies, we confirmed demineralized bone particle (DBP) had the power of the reduction of inflammatory reaction and the stimulation proliferation of cells. We fabricated PLGA scaffold loaded with 10, 20, 40 and 80 wt% DBP and then tested the possibility of the regeneration of cartilage using CCs. Assays of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and scanning electron microscope (SEM) carried out to evaluate the attachment and proliferation of CCs in DBP/PLGA scaffolds. Glycosaminoglycan (sGAG) and collagen contents assay were conducted to confirm the effects of DBP on formation of extracellular matrix. This study demonstrated that DBP/PLGA scaffolds showed significant positive effects on cell growth and proliferation due to the vitality of DBP as well as the possibility of the application of CCs for tissue engineered cartilage.

• Imaging Science in Dentistry
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• v.39 no.3
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• pp.121-132
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• 2009

Purpose : To investigate the effects of 2-deoxy-D-glucose (2-DG) and quercetin (QCT) on gene expression of bone sialoprotein (BSP) and osteocalcin (OC) during the differentiation in irradiated MC3T3-E1 osteoblastic cells. Materials and Methods : When MC3T3-E1 osteoblastic cells had reached 70-80% confluence, cultures were transferred to a differentiating medium supplemented with 5 mM 2-DG or $10{\mu}M$ QCT, and then irradiated with 2, 4, 6, and 8 Gy. At various times after irradiation, the cells were analyzed for the synthesis of type I collagen, and expression of BSP and OC. Results : The synthesis of type I collagen in cells exposed to 2 Gy of radiation in the presence of 2-DG or QCT showed no significant difference compared with the control group within 15 days post-irradiation. When the cells were irradiated with 8 Gy, 2-DG facilitated the irradiation mediated decrease of type I collagen synthesis, whereas such decrease was inhibited by treating with QCT. During MC3T3-E1 osteoblastic cell differentiation, the mRNA expression of BSP and OC showed the peak value at 14 days and 21 days, respectively. 2-DG or QCT treatment alone decreased the level of BSP mRNA, but increased the OC mRNA level only at early time of differentiation (day 7). In the cells irradiated with 2, 4, 8 Gy, the mRNA expression of BSP and OC decreased at 7 days after the irradiation. The cells were treated with various dose of radiation in the presence of 2-DG or QCT, the mRNA level of both BSP and OC increased although this increase was observed at low dose of radiation (2 Gy) and at the early stage of differentiation. However, when the cells were exposed to 4, 6, or 8 Gy, the increase of BSP and OC mRNAs was detected only in cells co-incubated with QCT. Conclusion : This study demonstrates that 2-DG and QCT affect differently the expression of bone formation related factors, type I collagen, BSP, and OC in the irradiated MC3T3-E1 osteoblasic cells, according to the dose of radiation and the times of differentiation. Overall, the present findings suggest that 2-DG and QCT could have the regulatory roles as radiation-sensitizer and -protector, respectively.