• Journal of Microbiology and Biotechnology
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• v.12 no.2
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• pp.318-326
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• 2002

The pathogenic marine bacterium Vibrio vulnificus is the causative agent of food-borne diseases such as life-threatening septicemia. To better understand this organism's strategies to survive osmotic stress, a mutant that was more sensitive to high osmolarity was screened from a library of mutants constructed by a random transposon mutagenesis. By a transposon-tagging method, putAP genes encoding a proline dehydrogenase and a proline permease were identified and cloned from V. vulnificus. The amino acid sequences deduced from nucleotide sequences of putAP from V. vulnificus were 38 to $59\%$ similar to those of PutA and PutP reported from other Enterobacteriaceae. Functions of putAP genes were assessed by the construction of mutants, whose putAP genes were inactivated by allelic exchanges. When proline as the sole carbon or nitrogen source was used, the putA mutant was not able to grow to the substantial level, revealing the proline dehydrogenase is the only enzyme for metabolic conversion of proline into other amino acids. Although the growth rate of the putP mutant on proline as the sole carbon or nitrogen source was significantly reduced, the mutant still grew. This indicated that at least one more proline permease is produced by V. vulnificus. The putP mutant decreased approximately $2-log_10$ CFU/ml after a hyperosmotic challenge, while the parent strain decreased approximately $l-log_10$ CFU/ml. This result suggests that the gene product of putP contributes to the osmotic tolerance of V. vulnificus.

• Journal of Surface Science and Engineering
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• v.13 no.3
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• pp.146-154
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• 1980

The effects of various electrodeposition conditions (deposition temperature and cathode current density) on preferred orientation and microhardness of electrodeposited Ni-Sn and Sn-Zn alloys were studied. At deposition temperatures from 25$^{\circ}$ to 95$^{\circ}C$ and constant cathode current density of 270 and 530 A/$m^2$ Ni-Sn and Sn-Zn were codeposited in chloride-fluoride acid and stannate-cyanide alkaline electrolyte bath respectively. Ni-Sn alloy deposited at temperatures from 25$^{\circ}$ to 35$^{\circ}C$ was composed of single phase of $Ni_3Sn_4$ with 73 wt.% Sn and the one deposited at temperatures from 45$^{\circ}$ to 95$^{\circ}C$ was made of multiphase mixture of NiSn, $Ni_3Sn_2$ and $Ni_3Sn_4$ with nearly equiatomic composition (65.5 wt.% Sn). The random orientation of thermody-namically metastable NiSn phase (hexagonal structure) predominated at deposition temperature range 25$^{\circ}$-45$^{\circ}C$, and the strong (110) preferred orientation was found at 65$^{\circ}$-85$^{\circ}C$ and then disappeared again at 95$^{\circ}C$. The microhardness of Ni-Sn deposits increased with deposition temperature up to 85$^{\circ}C$, and then decreased at constant cathode current density. The preferred orientation and the maximum microhardness were discussed in terms of lattice contractile stress which result from desorption of hydrogen atom absorbed in deposit lattice. The Sn content of Sn-Zn alloy deposits increased with deposition temperature up to 75$^{\circ}C$, and then decreased at constant cathode current density of 530 A/$m^2$. It also decreased with cathode current density up to 530 A/$m^2$, and then increased at constant deposition temperature of 25$^{\circ}C$. Sn-Zn alloy deposits were composed of two-phase mixture of ${beta}$-Sn and Zn. The preferred orientations of ${beta}$-Sn (tetragonal structure) changed with deposition temperature. The microhardness of Sn-Zn deposits decreased with deposition temperature. It also increased with cathode density up to 530 A/$m^2$, and then decreased at constant deposition temperature of 25$^{\circ}C$. The microhardness of Sn-Zn deposits was observed to be determinded more by the Sn content than by the preferred orientation.

• Korean Journal of Community Nutrition
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• v.13 no.2
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• pp.276-287
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• 2008

Diabetic mellitus in an older population is associated with increased basal oxidative stress and free radical accentuated by hyperglycemic challenge. Enhanced free radical in diabetic elderly can cause the oxidative damage and such damage can be protected by antioxidant defense system. It is believed that vitamin C, A and E are the most abundant and effective antioxidants in human plasma. The purpose of this study was to determine the antioxidant status in Korean diabetic elderly using the case-control study. The antioxidant status was examined by determining plasma levels of antioxidant vitamins (vitamin C, A, E, ${\beta}$-carotene), total antioxidant status (TAS) and thiobarbituric acid reactive substance (TBARS) and intakes of vitamin C, A, ${\beta}$-carotene and retiol. Fasting glucose and HbA1c levels and serum lipid profiles (triglyceride (TG), total cholesterol, HDL-cholesterol and LDL-cholesterol) were also determined. Diabetic subjects were 122 elderly persons over 60 years old, visiting public health center, and control subjects were 96 healthy elderly persons living in Ulsan, Korea and they were matched by age, gender, smoking and drinking status. The diabetic and control subjects were divided into sub-groups according to the status of using diet therapy and vitamin supplement. The subjects were interviewed to collect data on their general characteristics, disease history, vitamin supplement, diet therapy and health-related habits by questionnaires. Their dietary intakes were obtained by means of semi-quantitative food frequency questionnaires (SQFFQ). Fasting plasma glucose and HbA1c levels were significantly higher in diabetes than in control subjects, and plasma total cholesterol level of diabetes was not significantly different from that of control subjects. However serum HDL cholesterol level of diabetes was significantly lower and serum TG level of diabetes was significantly higher than those of control group. The average vitamin A and ${\beta}$-carotene intakes of diabetes were significantly higher than those of control subjects. There was no significant difference in plasma vitamin C, ${\beta}$-carotene, and TBARS levels between two groups, but plasma vitamin A, E and TAS levels were significantly higher in diabetes than those in control group. Plasma vitamin A and TAS levels of diabetic subjects using diet therapy were higher than those of control using diet therapy, and plasma vitamin E, ${\beta}$-carotene and TAS levels of diabetic subjects using vitamin supplements were significantly higher than those of controls using vitamin supplements. These results suggested that diabetic mellitus could enhance antioxidant defences against reactive oxygen species and interest in healthy eating such as consumption of more antioxidant nutrients.

• Korean Journal of Microbiology
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• v.54 no.3
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• pp.200-207
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• 2018

At high salt concentration, glycine betaine is transported into Bacillus subtilis and growing rate of the cell is not suppressed. Also according to recent studies, cell growth is maintained normal growth rate at low temperature. Low temperature results in a stress response of Bacillus subtilis that is characterized by strong repression of major metabolic activities such as translation machinery and membrane transport. In this regards, genes showing cold sensitive phenotype are cold-induced DEAD box RNA helicases (ydbR, yqfR) and fatty acid desaturases (bkdR, des). Therefore to understand the effect of glycine betaine on cold growth of Bacillus subtilis, we investigated the effect of glycine betaine on growth rate of these deletion mutants showing cold sensitive phenotype. Glycine betaine strongly stimulated growth of wild type Bacillus subtilis JH642 and deletion mutants of ydbR and yqfR at $20^{\circ}C$ (190~686 min $T_d$ difference). On the other hands, glycine betaine does not show growth promoting effects on deletion mutants of bkdR, and des at cold conditions. Same cold protectant growth results were shown with the precursor choline instead of glycine betaine. We investigated the effects of detergents on the cell membrane in bkdR and des deficient strains associated with cell membrane. It was identified that bkdR deficient strain shows retarded growth with detergent such as Triton X-100 or N-lauryl sarcosine compared with wild type cell. Thus, it is possible that deletion mutation of bkdR modifies membrane structure and effects on transport of glycine betaine.

• Journal of Society of Preventive Korean Medicine
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• v.15 no.1
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• pp.49-69
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• 2011

Objective : The object of this study was to observe the effects of Lonicerae Flos (LF) aqueous extracts on lipopolysaccharide (LPS)-induced rat acute lung injury. Method : Five different dosages of LF extracts were orally administered once a day for 28 days before LPS treatments, and then all rats were sacrificed after 5 hour-treatment of LPS. Eight groups of 16 rats each were used in the present study. The following parameters caused by LPS treatment were observed ; body weights, lung weights, pulmonary transcapillary albumin transit, arterial gas parameters (pH, $PaO_2$ and $PaCO_2$) bronchoalveolar lavage fluid (BALF) protein lactate dehydrogenase (LDH), and proinflammatory cytokines tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-$1{\beta}$ (IL-$1{\beta}$) contents, total cell numbers, neutrophil and alveolar macrophage ratios, lung malondialdehyde (MDA), myeloperoxidase (MPO), proinflammatory cytokines TNF-${\alpha}$ and IL-$1{\beta}$ contents. In addition, the histopathologic changes were observed in the lung in terms of luminal surface of alveolus, thickness of alveolar septum, number of polymorphonuclear neutrophils. Result : As results of LPS-injection, dramatical increases in lung weights, pulmonary transcapillary albumin transit increases, increases in $PaCO_2$, decreases in pH of arterial blood and $PaO_2$, increases of BALF protein, LDH, TNF-${\alpha}$ and IL-$1{\beta}$ contents, total cells, neutrophil and alveolar macrophage ratios, TNF-${\alpha}$ and IL-$1{\beta}$ contents increases were detected with decreases in LSA and increases of alveolar septum and PMNs numbers, respectively as compared with intact control. These are means that acute lung injuries (resembling acute respiratory distress syndrome) are induced by treatment of LPS mediated by inflammatory responses, oxidative stress and related lipid peroxidation in the present study. However, these LPS-induced acute lung injuries were inhibited by 28 days continuous pretreatment of 250 and 500mg/kg of LF extracts. Because of lower three dosages of LF treated groups, 31.25 and 62.5 and 125mg/kg did not showed any favorable effects as compared with LPS control, the effective dosages of LF in LPS-induced acute lung injuries in the present study, is considered as about 125mg/kg. The effects of 250mg/kg of LF extracts showed almost similar effects with ${\alpha}$-lipoic acid 60mg/kg in preventing LPS-induced acute lung injuries. Conclusion : It seems that LF play a role in protecting the acute respiratory distress syndrome caused by LPS.

• Journal of Preventive Medicine and Public Health
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• v.35 no.4
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• pp.282-286
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• 2002

Objectives : The level of 4-hydroxyproline (4-Hyp) in human urine was measured using high performance liquid chromatography (HPLC) with a fluorescence detector. This method is useful for medical examinations and investigating the radicals induced by physical, chemical, mental stresses. This method is superior to many published several methods in terms of its low cost and ability to analyze many samples. Methods : The urine from workers in a tire manufacturing company (22 male pre- and post-shift workers) and 18 office-workers as controls were analyzed. Data concerning age, the cumulative drinking amount and the cumulative smoking amount was collected with a questionnaire. The optimum applied amount of dansyl-Cl, the optimum reaction temperature and time, the recoveries and the optimum pH of the eluent and buffer were determined.4-Hyp from human urine was derivatized with dansyl-Cl (dimethylamino-naphthalene-1-sulfonyl chloride) after removing the a-amino acid by a treatment with phthalic dicarboxaldehyde (OPA) and cleaned with Bond Elut C18 column. The 4-Hyp derivatives were separated on a reversed phase column by gradient elution with a phosphate buffer (5 mmol, pH 8.0) and acetonitrile, and detected by fluorescence measurements at 340 nm (excitation) and 538 nm (emission). Results : The detection limit for the urinary free 4-Hyp was $0.364{\mu}mol/l$. The recovery rate of 4-Hyp was 99.7%, and the effective pH of the phosphate buffer and borate buffer were 3.0 and 8.0, respectively. From statistical analysis, age, drinking and smoking did not affect the urinary free 4-Hyp in both the controls and workers. The range of urinary 4-Hyp in the controls, pre-shift, and post-shift workers were 0.33-16.44, N.D-49.06, and $0.32-56.27{\mu}mol/l$. From the pared-sample t-test, the urinary 4-Hyp levels in post-shift workers ($11.82{\pm}6.73\;nmmol/mg\;Cre$) were 2-fold higher than in pre-shift workers ($5.36{\pm}5.53\;nmol;/mg\;Cre$) and controls ($4.91{\pm}4.89\;nmol;/mg\;Cre$). Conclusions : This method was developed with high sensitivity, accuracy, and precision. The present method was effectively applied to analyze the urinary free 4-Hyp in both controls and workers.

• Journal of Life Science
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• v.26 no.2
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• pp.164-173
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• 2016

Isotocin (IT), a nonapeptide homolog of oxytocin in mammals, has been suggested to be involved in physiological processes including social behaviors, stress responses, and osmoregulation in teleost fish. To study its structure and function, the gene encoding the IT precursor was cloned from the genomic DNA and brain cDNA of the cinnamon clownfish, Amphiprion melanopus. The IT precursor gene consists of three exons separated by two introns, and encodes an open reading frame of 156 amino acid (aa) residues, comprising a putative signal peptide of 19 aa, a mature IT protein of 9 aa, a proteolytic processing site of 3 aa, and 125 aa of neurophysin. Tissue-specific analysis of the IT precursor transcript indicated its expression in the brain and gonads of A. melanopus. To examine its osmoregulatory effects, the salinity of the seawater (34 ppt) used for rearing A. melanopus was lowered to 15 ppt. Histological analysis of the gills indicated the apparent disappearance of an apical crypt on the surface of the gill lamella of A. melanopus, as pavement cells covered the surface upon acclimation to the lower salinity. The level of Na⁺/K^+-ATPase activity in the gills was increased during the initial stage of acclimation, followed by a decrease to its normal level, suggesting its involvement in osmoregulation and homeostasis. The only slight increase in the level of IT precursor transcript in the A. melanopus brain upon low-salinity acclimation suggested that IT played a minor role, if any, in the process of osmoregulation.

• Resources Recycling
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• v.29 no.1
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• pp.25-34
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• 2020

Electrochemical Quartz Crystal microbalance is a tool that is capable of measuring nanogram-scale mass change on electrode surface. When applying alternating voltage to the quartz crystal with metal electrode formed on both sides, a resonant frequency by inverse piezoelectric effect depends on its thickness. The resonant frequency changes sensitively by mass change on its electrode surface; frequency increase with metal dissolution and decrease with metal deposition on the electrode surface. The relationship between resonant frequency and mass change is shown by Sauerbrey equation so that the mass change during metal dissolution can be measured in real time. Especially, it is effective in the case of reaction mechanism and rate studies accompanied by precipitation, volatilization, compound formation, etc. resulting in difficulties on ex-situ AA or ICP analysis. However, it should be carefully considered during EQCM experiments that temperature, viscosity, and hydraulic pressure of solution, and stress and surface roughness can affect on the resonant frequency. Application of EQCM was shown as a case study on leaching of platinum using aqueous chlorine for obtaining activation energy. A platinum electrode of quartz crystal oscillator with 1000 Å thickness exposed to solution was used as leaching sample. Electrogenerated chlorine as oxidant was purged and its concentration was controlled in hydrochloric acid solution. From the experimental results, platinum dissolution by chlorine is chemical reaction control with activation energy of 83.5 kJ/mol.

• Korean Journal of Plant Resources
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• v.31 no.4
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• pp.312-321
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• 2018

Angelica tenuissima, also known as Ligusticum tenuissimum, is classified as a food-related plant and has been used as traditional medicines treating headache and anemia in Asia. However, its anti-melanogenic effect has not been reported in detail. When the extract of Angelica tenuissima (ATE) was prepared by the extraction with 70% EtOH at $80^{\circ}C$ (final yield = 22%), the contents of decursin and Z-ligustilide in ATE were determined 0.06% and 8.43%, respectively. Total flavonoid and phenolic content in mg ATE were $5.52{\pm}0.07{\mu}g$ quercetin equivalents and $237.27{\pm}13.24{\mu}g$ gallic acid equivalents, respectively. Antioxidant capacity of ATE determined by DPPH and ABTS assay was increased with a dose dependent manner up to $1000{\mu}g/m{\ell}$. The amount of melanin synthesis followed by ${\alpha}-melanocyte$ stimulating hormone on B16F10 cells were significantly reduced in the presence of ATE (250 to $1000{\mu}g/m{\ell}$, p<0.05). ATE (125 to $1000{\mu}g/m{\ell}$, p<0.05) suppressed the tyrosinase activity but did not show any significant effect on ${\alpha}-glucosidase$ activity at the same condition. Taken together, ATE possesses tyrosinase inhibitory potential with significant antioxidant capacities. These effects of ATE might be involved in suppression of melanin synthesis, at least, in B16F10 cells. The anti-melanogenic potential of ATE will provide an insight into developing a new skin whitening product.

• Journal of Sericultural and Entomological Science
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• v.53 no.2
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• pp.71-77
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• 2015

Much attention has been focused on the activity of the natural antioxidants present in fruits and vegetables, because potentially these components may reduce the level of oxidative stress. Especially, mulberry leaves containing many natural components are considerable resource for natural antioxidants. The antioxidant capacity of mulberry leaves was investigated with minilum L-100 device and ARAW-KIT (anti-radical ability of water-soluble substance), in comparison to the ascorbic acid. The antioxidant capacity of 16 varieties was 3303.4 nmol at opening stage of five leaves in spring. The highest stage of antioxidant capacity (3708.0 nmol) and yield rate was just before the coloration stage with anthocyanin in fruits, whereas the lowest stage was middle of June (2231.6 nmol) and about two months growing stage after summer pruning (2064.6 nmol). But after summer pruning, the antioxidant capacity of mulberry leaves increased gradually until just before fallen leaves stage. Even if samples were same variety, antioxidant effect of those showed different results according to collected regions. Also, antioxidant effect of mulberry leaves were higher than that of branches. The antioxidant capacity of yield-type mulberry leaves and fruits (Morus alba L., M. bombycis Koidz, and M. Lhou (Ser.) Koidz) collected from In-je, Won-ju and Yang-yang regions, Kang-won province, Korea, was investigated. The results indicated that total antioxidant capacity of yield-type mulberry leaves was 2711.2 nmol. In the antioxidant capacity analysis of Jeollabuk-Do genetic resources, autumn's mulberry leaves showed higher antioxidant capacity than that of spring's it. To investigate the effect of tea on antioxidative capacity, five kinds of tea(coffee mix, green tea added brown rice, mulberry leaf tea, Polygonatum odoratum tea and black tea added lemon) were selected and analyzed. Their's anti-oxidative capacity were 2,531.01 nmol, 1,867.42 nmol, 1,053.72 nmol, 292.71 nmol and 188.91 nmol, respectively. The antioxidative capacity of drinking water soaked with mulberry leaf showed 891.96 nmol.