• Microbiology and Biotechnology Letters
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• v.15 no.2
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• pp.84-88
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• 1987

Poly(ethylene glycol)-PPB two phase system was used tot the purification of $\beta$-galactosidase from Lactobacillus sporogenes. The smaller the molecular weight of concentration of PEG phase in-creased, proteins as well as $\beta$-galactosidase was partitioned into the top phase. All cell debris were confined to the potassium phosphate phase (bottom phase), approached to the binodial line. The purification ratio increased by changing the polymer-salt composition of the tie line towards higher salt concentrations. It was also possible to obtain higher purification of the enzyme after two-step extraction using PEG 1000 and PEG 300. The top phase contained 74% of the total $\beta$-galactosidase with a purification factor of 2.1.

• Journal of Periodontal and Implant Science
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• v.44 no.3
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• pp.141-146
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• 2014

Purpose: Peri-implantitis and periodontitis are inflammatory and infectious diseases of implant and tooth-supporting tissues. Recently, the role of gene polymorphisms of immune response components in the relevant pathogenesis has been investigated. The present study was the first to evaluate the relationship between two known single nucleotide polymorphisms (SNPs) of the receptor activator of nuclear factor kappa-${\beta}$ (RANK) gene (rs3018362 and rs35211496) in chronic periodontitis and peri-implantitis patients in an Iranian population. Methods: Eighty-one periodontally healthy patients, 38 patients with peri-implantitis, and 74 patients with chronic periodontitis were enrolled in this study. DNA was extracted from blood arm vein samples by using Miller's salting out technique according to the manufacturer's instructions given in the extraction kit. The concentration of DNA samples was measured using a spectrophotometer. The genetic polymorphisms of the RANK gene were evaluated using a competitive allele specific polymerase chain reaction (KBioscience allele specific PCR) technique. Differences in the frequencies of genotypes and alleles in the diseased and healthy groups were analyzed using chi-squared statistical tests (P<0.05). Results: Analysis of rs35211496 revealed statistically significant differences in the expression of the TT, TC, and CC genotypes among the three groups (P=0.00). No statistically significant difference was detected in this respect between the control group and the chronic periodontitis group. The expression of the GG, GA, and AA genotypes and allele frequencies (rs3018362) showed no statistically significant difference among the three groups (P=0.21). Conclusions: The results of this study indicate that the CC genotype of the rs35211496 RANK gene polymorphism was significantly associated with peri-implantitis and may be considered a genetic determinant for peri-implantitis, but this needs to be confirmed by further studies in other populations.

• Korean Journal of Agricultural Science
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• v.14 no.1
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• pp.144-155
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• 1987

A potent fungus producing milk clotting enzyme with fairly weak proteolytic activity was isolated from various soil and sewage, which the selected strain, SA-101, was identified as Mucor sp. with microbiological characteristics. Its milk clotting enzyme production was maximized when grown on 10g of wheat bran media added to 8ml of tap water containing 0.1M HCl for 60hrs at $30^{\circ}C$. This enzyme production was stimulated by addition of 6% lactose, 0.05% NaCl and reached a maximal level of 9810 unit/g wheat bran. The crude enzyme product could be produced effectively by salting out with ammonium sulfate fractionation and lyophilization. The ratio of milk clotting activity to proteolytic activity of crude enzyme product was lower than Hansen rennet, but resembled to Meito rennet. The optimal temperature of milk clotting activity of crude enzyme product was abound $60^{\circ}C$ on a substrate of 10% reconstituted skim milk containing 1/100M $CaCl_2$.

• Food Science and Preservation
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• v.7 no.4
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• pp.343-348
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• 2000

Characteristics of major suing Chinese cabbage cultivars in Korea, Norangbom(Nor), Gonaenggiyeurum(Gon), Maereuk (Mae) and Housekumgarak (Hou), and their qualities of Kimchies were investigated. Mean weight of the cabbages was in the range of 1.39∼2.40 kg, and was higher Gon, Mae, Nor, Hou in order. Leaves number was Gon 45, Nor 56, Mae 59 and Hou 56 pieces. Sensory taste of raw Chinese cabbage was best in Nor. Decreasing rate of gumminess and chewiness by salting was the highest in Gon and the lowest in Nor. fermentation of Gon and Nor-Kimchi were faster than Mae and Hou-Kimchi. Amount of gas formation during fermentation was the highest in Mae-Kimchi and lowest in Nor-Kimchi. Decreasing rate of AIS was the fastest in Mae-Kimchi and the latest in Hou-Kimchi. Hardness and gumminess of Kimchi fermented for 21 days were to be ordered Mae-Kimchi, Hou-kimchi, Gon-Kimchi and Nor-Kimchi. Overall acceptability by the sensory test was good in Nor- and Hou-Kimchi.

• Korean Journal of Food Science and Technology
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• v.8 no.3
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• pp.141-146
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• 1976

1) The purified enzyme was obtained with the specific activity 126.5 u/mg protein (about 45 times of the original activity) and the yield of 4.2%, by means of salting out with ammonium sulfate (0.5 saturation) of the crude enzyme solution, desalting by Sephadex G 25, CM cellulose columm chromatography, concentration by Sephadex G 25, and gel filtration by Sephadex G 75. 2) In the acrylamide gel disc electrophoresis of the purified enzyme, the main band and two obscure ones on the both side of the main band appeared, which indicated that the enzyme was considerably purified compared with its crude enzyme solution, even if it is not referred to as a pure protein.

• Journal of the Society of Disaster Information
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• v.13 no.4
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• pp.562-569
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• 2017

Reinforced concrete is used for bridges and large structures that are constructed with social overhead capital because they are economically and semi-permanently integrated with reinforcing bar and concrete. However, when the chloride ion in the concrete destroys the passive film of the reinforcing bar by the marine exposure environment and the snow remover used in the winter season, and the reinforcing bar is corroded by various chemical and physical actions, the durability is deteriorated in a short period, and the life span is shortened. In this study, a repair method to recover the durability of the initial structure by effectively removing chloride ion from the damage caused by salting of the above mentioned reinforced concrete was conducted.

• Korean Journal of Microbiology
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• v.18 no.4
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• pp.161-171
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• 1980

A mutant strain having increased productivity of both enzymes, protease and amylase, was obtained from A. flavus KU 153, isolatd from South Korea for its high protease production by successive ultra-violet light irradiation, Two glucoamylases from the mutant strain selected were purified from wheat branculture by successive salting out, followed by dialysis and column chromatography, and their characteristics were compared with those of the wild strain. Glucoamylase production of the mutant selected was increased about 3.3 times compared with the wild strain, and 2.1 times compared with the parental strain, ${\alpha}-amylase$ activity of the mutant selected was about 2 times hugher than that of the wild strain or the parental strain. Protease and cellulase productivities of the muant selected were all alike compared with those of the highly proteolytic mutant, the parental strain. Therefore, it was considered that the back mutation on the protease production did not occurred in the formation process of the glucoamylase producing mutant. Total activities of glucoamylase I and II from the mutant selected were 2.86 and 3.65 times higher compared with those from the wild strain, respectively. Considering the optimal pH-thermal stability and Km-Vmax value of glucoamylase I and II from both strains, wild and mutant, it was deduced that the characteristics of glucoamylase I and II from the wild strain did not altered during the mutation process. Therefore, it was concluded that the selected mutant did not induce the formation of another glucoamylase isozyme, or the changes in the characteristics of the glucoamylase, but induce the productivity of the same glucoamylase I and II by the action of regulatory gene.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.325-329
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• 1991

Changes in thermal conductivity of petiole tissue of Chinese cabbage during steam heating and salting were measured by probe method. The thermal conductivity($k_e,\;W/m{\cdot}K$) of the tissue decreased with the increase in gas content and the decrease in moisture content. The correlating equation. $k_e=0.0192$ MC-0.6284 $V_a-1.3252$, obtained over the range of moisture content(MC) of 92 to 96% and gas content($V_a$) of 0 to 0.15 ml/g cabbage at $30^{\circ}C$ The thermal conductivity of salted cabbage was about $0.04\;W/m{\cdot} K$ higher than that of raw cabbage at the same moisture content.

• Journal of Life Science
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• v.7 no.3
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• pp.228-233
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• 1997

A thiol protease has been isolated and partially purified from encysted brine shrimp Artemia franciscana using a four-step procedure(filtration, salting out, gel filtration and ion exchange chromatography). The optimum pH of the enzyme for caseinolytic activity was appeared to be 3.0, and the enzymematic activity was stable up to pH 6.0 but lost completely at the pH higher than 8.0. The optimal temperature of the enzyme was appeared to be 35$^{\circ}$C, and ninety percent of the enzyme activity was lost at 45$^{\circ}$C. Various metal ions, e.g., zinc, copper, iron, inhibited the enzyme activity; however, heavy metal chelator, e.g., EDTA, stimulated the enzyme activity. The protease was concluded to be a member of the thiol group protease, since it was inhibited by thiol protease inhibitors and iodoacetate. The protease was also concluded to be a acid protease based on optimum pH.

• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.30-36
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• 1996

This study was conducted to investigate the changes in chemical, microbial, sensory characteristics and volatile flavor components of wooung(burdock, Arctium lappa, L) kimchi during fermentation at 15$^{\circ}C$, Three types(A, B, C) of wooung kimchi were prepared. Sample A was prepared with basic ingredients, in the other hand, sample B was prepared with all sorts of ingredients. These samples were mixed after salting the sliced burdock with 4% brine for 30min. Sample C was prepared mixing with all sorts of ingredients after blanching the sliced burdock with 2% vinegar solution. pH decreased slowly until 3 day, and then decreased rapidly for 4~7 days in all samples. Total acidity increased gradually in all samples. The changes of pH and total acidity were the sample C and were the greatest in sample B. The reducing sugar contents decreased slowly until 7 day, and decreased rapidly for 8~14 days in sample A and B, and at 10 day in sample C, respectively. The numbers of lactic acid bacteria and total bacteria of sample B were much greater than those of other sample. In sensory evaluation, sample B exhibited the best scores and sample C showed the worst scores in all characteristics. The major volatile components in wooung kimchi were identified as ethanol, hexanal, 2-hexenal, disulfide dl- 2-prophenyl, zingiberene and $\beta$-sesquiphellandrene. The relative amounts of hexanal, 1-hexanol and ethanol were decreased, while the relative amounts of acetic acid ethyl ester, 3-htdroxy-2-butanone and acetis acid were increased gradually during fermentation.