• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.4
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• pp.341-350
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• 2015

Skin carrys out protective role against harmful outer environment assaults including ultraviolet radiation, heavy metals and oxides. Especially, ultraviolet-B (UVB) light causes inflammatory reactions in skin such as sun burn and erythma and stimulates melanin pigmentation. Furthermore, the influx of UVB into skin cells causes DNA damage in keratinocytes and dermal fibroblasts, inhibition of extracellular matrix (ECM) synthesis which leads to a decrease in elasticity of skin and wrinkle formation. It also damages dermal connective tissue and disrupts the skin barrier function. Prolonged exposure of human skin to UVB light is well known to trigger severe skin lesions such as cell death and carcinogenesis. Haloarcula vallismortis is a halophilic microorganism isolated from the Dead Sea, Its growth characteristics have not been studied in detail yet. It generally grows at salinity more than 10%, but the actual growth salinity usually ranges between 20 to 25%. Because H. vallismortis is found mainly in saltern or salt lakes, there could exist defense mechanisms against strong sunlight. One of them is generation of additional ATP using halorhodopsin which absorbs photons and produces energy by potential difference formed by opening the chloride ion channel. It often shows a color of pink or red because of their high content of carotenoid pigments and it is considered to act as a defense mechanism against intense UV irradiation. In this study, the anti-inflammatory effect of the halophilic microorganism, H. vallismortis, extract was investigated. It was found that H. vallismortis extract had protective effect on DNA damage induced by UV irradiation. These results suggest that the extract of halophilic bacterium, H. vallismortis could be used as a bio-sunscreen or natural sunscreen which ameliorate the harmful effects of UV light with its anti-inflammatory and DNA protective properties.

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.1080-1086
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• 2005

Membranes prepared from Vibrio natriegens oxidized both NADH and deamino-NADH as substrates. The maximum activity of the membrane-bound NADH oxidase was obtained at about pH 8.5 in the presence of 0.2 M NaCl, whereas that of the NADH:ubiquinone oxidoreductase was obtained at about pH 7.5 in the presence of 0.2 M NaCl. Electron transfer from NADH or deamino-NADH to ubiquinone-l or oxygen generated a considerable membrane potential (${\Delta}{\psi}$), which occurred even in the presence of $20{\mu}M$ carbonylcyanide m-chlorophenylhydrazone (CCCP). However, the ${\Delta}{\psi}$ was completely collapsed by the combined addition of $10{\mu}M$ CCCP and $20{\mu}M$ monensin. On the other hand, the activity of the NADH oxidase and the ${\Delta}{\psi}$ generated by the NADH oxidase system were inhibited by about $90\%$ with $10{\mu}M$ HQNO, whereas the activity of the NADH:ubiquinone oxidoreductase and the ${\Delta}{\psi}$ generated at the NADH:ubiquinone oxidoreductase segment were inhibited by about $60\%$. Interestingly, the activity of the NADH:ubiquinone oxidoreductase and the ${\Delta}{\psi}$ generated at the NADH:ubiquinone oxidoreductase segment were resistant to the respiratory chain inhibitors such as rotenone, capsaicin, and $AgNO_3$, and the activity of the NADH oxidase and the ${\Delta}{\psi}$ generated by the NADH oxidase system were very sensitive only to $AgNO_3$. It was concluded, therefore, that V. natriegens cells possess a $AgNO_3$-resistant respiratory $Na^+$ pump that is different from the $AgNO_3$-sensitive respiratory $Na^+$ pump of a marine bacterium, Vibrio alginolyticus.

• Journal of Microbiology
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• v.42 no.3
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• pp.174-180
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• 2004

A halophilic bacterium was isolated from fermented seafood. The 16S rDNA sequence identity between the isolate and Halomonas subglaciescola AJ306801 was above 95％. The isolate that did not grow in the condition without NaCl or in the condition with other sodium (Na$\^$+/) or chloride ions (Cl$\^$-/) instead of NaCl was named H. subglaciescola DH-l. Two mutants capable of growing without NaCl were obtained by random mutagenesis, of which their total soluble protein profiles were compared with those of the wild type by two-dimensional electrophoresis. The external compatible solutes (betaine and choline) and cell extract of the wild type did not function as osmoprotectants, and these parameters within the mutants did not enhance their growth in the saline environment. In the proton translocation test, rapid acidification of the reactant was not detected for the wild type, but it was detected for the mutant in the condition without NaCl. From these results, we derived the hypothesis that NaCl may be absolutely required for the energy metabolism of H. subglaciescola DH-l but not for its osmoregulation, and the mutants may have another modified proton translocation system that is independent of NaCl, except for those mutants with an NaCl-dependent system.

• Microbiology and Biotechnology Letters
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• v.32 no.4
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• pp.362-365
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• 2004

The fucoidan from Laminaria relicollected at Wando in Korea was purified with the yield of 2.3% in mass. The monosaccharide composiof the purified fucoidan was nearly identical to that of the commercial standard: fucose 63.71 %, xylose 22.98%, galactose 6.62%, mannose 0.24%, and uronic acid 3.26%. Microorganisms capable of degrading the purified fucoidan were isolated from the colonies on the minimal medium containing 0.2% of purified fucoidan as a sole carbon source. Of these isolates, a strain showing a relatively higher capability to degrade fucoidan, up to 63%, was partially characterized as a Gram positive, aerobic, moderately halophilic marine bacterium.

• Journal of Life Science
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• v.15 no.4 s.71
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• pp.578-583
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• 2005

Cell-free culture broth of marine halophilic bacterium, Kordia algicida was shown to possess specific algicidal ability against red tide organism, Cochlodinium polykrikides. Physiochemical characteristics of algicidal material originated in the bacterial culture broth were analyzed that its molecular weight was estimated to a 3,000 dalton and it was stable in heat and pH treatment. The algicidal fraction against C. polykrikoides obtained from gel permeable chromatography contained high concentration of ammonium ion as analyzed by ICP/Mass spectrum. C. polykrikoides by the fraction was quickly lysed within 1 min. It was shown that the effective concentration for algicide against C. polykrikoides was over 1mM of ammonium chloride. On the other hand, other metal ions presented in the algicidal fraction showed no algicidal effect against C. polykrikoides. In additon, ammonium ion exhibited species-specific killing spectrum for two species of red tide organisms, C. polykrikoides and Gymnodinium sanguieum. Therefore, further researches on the killing mechanism against C. polykrikoides exerted by ammonium ion, and subsequent development of replaceable algicidal materials will perform to provide useful tools for the control of red tide.

• Microbiology and Biotechnology Letters
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• v.35 no.4
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• pp.298-303
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• 2007

A halophilic bacterium, H. subglaciescola DH-1, grew at 2.0 M salinity, but did not grow at 0.8 M salinity when cultivated at higher temperature ($40^{\circ}C$) than optimum ($30^{\circ}C$). When the cell extract of strain DH-1 was heated at $50^{\circ}C$ for 60 min in the absence of NaCl, isocitrate dehydrogenase and malate dehydrogenase lost their activities, but when it was heated in the presence of 2.0 M NaCl, the activity was maintained. Meanwhile, the cell extract of E. coli did not catalyze the reduction of $NAD^+$ to NADH coupled with the oxidation of isocitrate and malate at higher salinities than 1.0 M. The pH range for DH-1 was 7 to 10, and that for E. coli was 5 to 9. DH-1 was not grown in conditions with sodium salts other than NaCl.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.1
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• pp.143-151
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• 2001

A marine bacterium producing carotenoid was isolated from the Yosu coastal area of South Korea, which was recorded as MCK-1. It was identified as Erythrobacter sp. Optimium conditions of marine carotenoid fermentation from Erythrobacter sp. were pH 6.0, a temperature of $25^{\circ}C$, 16 mM mannitol as a carbon source, 0.5% tryptone as a nitrogen source, 0.1 mM $Fe^{+2}$ ion as a mineral source and 1$\mu$M of cyanocobalamine as a growth factor in a jar-fermentor. Erythrobacter sp. was produced 351.27 mg/100mL of the marine carotenoid in these optimum conditions. This marine carotenoid was composed of 4 different conpounds, like as notoxanthin (61.4%), can thaxanthin (24.6%), fucoxanthin (8.2%), and zeaxanthin (5.8%). Physiological properties including antibacterial activity, cytotoxic effect, antioxidative effect and free radical scavenging activity were characterized with crude carotenoid. Carotenoid exhibited no antibacterial activity against E. coli and lactobacillus bulgaricus, but showed cytotoxic effect against cancer cells such as HepG2 (Hepatocellular carcinoma, human, ATCC HB-8065) and HeLa (Cervical carcinoma, human, ATCC CCL-2) cells. The impediment ratios for HepG2 and HeLa cell were 37.14% and 33.78%, respectively. This carotenoid expressed a strong antioxidative effect (77%) against CCL-13 5 $\mu\textrm{g}$/mL and 50 $\mu\textrm{g}$/mL crude carotenoid, respectively.

• Journal of Microbiology
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• v.39 no.4
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• pp.279-285
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• 2001

Vibrio parahaemolyticus is a halophilic bacterium associated with seafood gastroenteritis. An unusual strain of Kanagawa-positive urease producing Vibrio parahaemolyticus O1:K1 was isolated from the environment and identified . A polymerase chain reaction assay revealed that this strain harbored both the tdh and the genes. The urease from this strain was studied. Maximum urease production was induced in LB medium containing 0.2% urea, 0.5% glucose, 2% NaCl and pH 5.5 with 6h of culti-vation at 37$\^{C}$ under aeration. Purification of urease was achieved by the process of whole cell lysate, 65% ammonium sulphate precipitation, DEAE-cellulose ion exchange column chromatography, Sepharose CL-6B gel filtration and oxirane activated Sepharose 6B-urea affinity chromatography with 203 fold purification and 2.2% yield. Analysis of the purified enzyme by SDS-PAGE demonstrated the presence of the subunits with a molecular weight of 85kDa, 59kDa, 41kDa and the molecular weight for the native enzyme by nondenaturing PAGE and gel filtration chromatography was 255kDa. The purified urease was stable at pH 7.5 and the opeimal pH in HEPES buffer was 8.0 The enzyme was stable at 60$\^{C}$ for 2 h with a residual activity of 32% . The addition of 10$\mu$M if NiCl$_2$maintained stability for 30 min. The Km value of the purified enzyme was 35.6 mM in urea substrate. The TD$\_$50/(median toxic dose) of the purified urease was 2.5$\mu\textrm{g}$/ml on human leukemia cells.

• The Journal of the Korean Society for Microbiology
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• v.22 no.4
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• pp.393-402
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• 1987

The halophilic bacterium Vibrio vulnificus, previously called lactose-positive(L+) Vibrio and Beneckea vulnifica, causes acute, fulminating wound infections and septicemia in humans. Septicemia is very serious infection with a fatality rate of about 50%. Most patients with primary septicemia due to V. vulnificus have preexisting liver disease. V. vulnificus also cause severe wound infections usually after trauma and exposure to marine animals or the marine environment. The mortality rate is not nearly as high as in primary septicemia caused by this organism. In most cases human disease results from ingestion of contaminated seafood or from infection of a wound, frequently of seawater or crab origin. The author made an attempt to isolation of the V vulnificus from seawater, seamud, fish, shellfish, and algae on the southern sea of Korea from January to September in 1987, using for the purpose of vaccine preparation. The author investigated for bacteriological identification, hemolysis and determination of serotypes of isolated V. vulnificus strains. Eighty-five strains(5.9%) out of 1450 specimens collected of V. vulnificus were isolated. The distribution of the 85 isolates were as follows: 21 strains from seawater, 11 strains from seamud, 28 strains from fish, 19 strains from shellfish, and 6 strains from algae, respectively. All 85 isolates were positive reaction on human blood agar. The distribution of serotypes of V. vulnificus isolates were O1 to O8: 13 strains of O1, 6 strains of O2, 11 strains of O3, 9 strains of O4, 10 strains of O5, 7 strains of O6, 15 strains of O7, and 10 strains of O8, respectively. Eighty-one strains showed agglutination with O antisera, but 4 strains failed to show agglutination. In this study, the author suspected that serotypes of V. vulnificus isolates distributed also in the seaside of Korea as well as in most seaside of the world, and new serotypes were in existence in the seaside of Korea except reported up to now.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.367-376
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• 1997

Vibrio vulnificus is a gram-negative, halophilic, oxidase-positive, lactose-positive, motile, rod shaped bacterium that has been associated with primary septicemia and wound infection. Elucidating the growth and survival of V. vulnificus in ecological conditions is of great importance to develop sanitary measure against this microorganism. Thus we simulated the ecological conditions and evaluated the effect. About $10^5\;CFU/ml$ of V. vulnificus was inoculated to fresh water, brackish water $(1\%\;NaCl)$, sea water $(3\%\;NaCl)$, and bottom deposit solution. The same concentration of V. vulnificus was also inoculated to distilled water, $1\%\;NaCl$ solution and $3\%\;NaCl$ solution as controls. These were stored at 4, 15 and $25^{\circ}C$, respectively and were used to assess the effects of temperature and salinity on the survival of V. vulnificus. In fresh water V. vulnificus could not survive regardless of storage temperature. In case of brackish water and sea water survival time of V. vulnificus was the longest at $25^{\circ}C$, and the number of V. vulnificus was decreased most rapidly at $4^{\circ}C$. V. vulnificus survived longer in brackish water than in any other conditions. In bottom deposit solution containing brackish water, the survival time of V. vulnificus was longer and the rate of decline was slower than that in brackish water. These results indicate that both biological and physicochemical factors such as temperature and salinity could affect survival of V. vulnificus. V. vulnificus, damaged in normal fresh water, did not grow on TCBS agar of selective plating medium but grew on BHI agar plate; However, V. vulnificus was recovered by addition of salt and nutrient materials.