• Korean Journal of Veterinary Research
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• v.42 no.3
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• pp.363-370
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• 2002

For the development of diagnostic polymerase chain reaction (PCR) to fungal infection by dermatophytes Trichophyton and Microsporum, detection of the fungal DNA by PCR and analysis of the DNA pattern were undertaken in the present study. A total of 15 strains were tested and those consisted of 3 reference strains and 12 isolates such as: reference strains of T mentagrophytes (downy type, ATCC 9533), T rubrum (IFO 6204) and M gypseum (ATCC 9083), and each isolate of T mentogrophytes (powdery type), T mentagrophytes (granular type), T mentogrophytes (purple-red type), T rubrum, T raubitschekii, T tonsurans, T equinum, T ajelloi, T verrucosum, M cookei, M nanum and M gypseum. The DNA were purely isolated from all strains of Trichophyton spp. and Microsporum spp. by a simple method partly consisted of disruption of fungal cells by lyophilization and grinding and extraction of fungal DNA without phenol treatment which is a routine procedure in DNA isolation. For the detection of fungal DNAs, optimal condition of PCR was determined as preheating once at $94^{\circ}C$ for 5 min, 35 cycles of denaturation at $94^{\circ}C$ for 1 min, annealing at $38^{\circ}C$ for 1 min and polymerization at $72^{\circ}C$ for 2 min, and 1 cycle of final extension at $72^{\circ}C$ for 5 min. In PCR using arbitrary primers AP-1 (5' ACCCGACCTG3') and AP-2 (5' ACGGGCCAGT3'), DNAs in various numbers and sizes were detected from different species of Trichophyton and Microsporum, while DNAs in similar size were also detected in all strains of Trichophyton spp. and Microsporum spp. There were unique DNAs observed from certain dermatophytes by AP-1 such as 1,900 bases in T rubrum, 950 and 1,100 bases in T raubitscheldi, 2,100 bases in T equinum, 400 bases in T verrucosum and 1,150 bases in M gypseum. The unique DNAs were also observed by AP-2 such as 1,200 bases in T ajelloi, 250 bases in T verrucosum, 1,150 bases in M cookei and 2,000 bases in M nanum. The results indicated that PCR can detect a specific DNA from certain Trychophyton and Microsporum spp, which can be the information for further development of diagoomc PCR to dennatophytes.

• Applied Biological Chemistry
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• v.36 no.3
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• pp.163-171
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• 1993

The collagens from filefish (Novoden modestus) and cod (Gadus macrocephalus Tilesius) skin were isolated and their physicochemical properties were investigated. Glutamic acid, hydroxyproline, valine and phenylalanine in the filefish skin collagen (FSC) were presented at higher levels than those of cod skin collagen (CSC), but the contents of glycine, proline and serine were contrary. The content of essential amino acids of FSC (265 residues/1000 residues) was higher than CSC (229 residues). The solubilities of both collagens were the lowest at pH 7.0, but precipitously increased at acid zone(below pH 5.0). FSC has lower viscosity than CSC. Furthermore, while the viscosities of both collagens were the lowest at pH 7.0, the viscosities of FSC and CSC were the highest at pH 4.0 and pH 2.0, respectively. The denaturation temperature of $FS(25^{\circ}C)$ was higher than $CSD\;(17^{\circ}C)$. The free hydrophobic residue contents of FSC and CSC tended to increase till $60^{\circ}C,\;and\;50^{\circ}C$ respectively, and to decrease thereafter. Hydration capacities of both collagens were the lowest at pH 7.0, and CSC had the superior hydration capacity to FSC. In addition, emulsifying and emulsifying stability of CSC was also superior to FSC.

• Analytical Science and Technology
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• v.29 no.2
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• pp.73-78
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• 2016

Hydrogen cyanide (HCN) is an extremely toxic gas frequently produced during the incineration of plastics, such as acrylonitrile-butadiene-styrene (ABS). A victim of a fire who has inhaled smoke could have cyanide in the blood. Therefore, cyanide could be a good marker for a post-mortem examination of a fire as well as carboxyhemoglobine (COHb) test of blood samples. For a particular fire case, a burned body with a suicide note was found inside a burned vehicle. Even though the COHb value is conclusive evidence, measuring the COHb for denatured blood might be difficult due to severe thermal denaturation or the formation of methemoglobin (MetHb). To overcome this difficulty, cyanide could be used as an indicator when investigating the death of a fire victim. In this study, gas chromatography/mass spectrometry (GC/MS) was adopted to measure the levels of cyanide in the blood through derivatization with pentafluorobenzyl bromide (PFBBr) under cation surfactant by scan and SIM mode. The concentration of cyanide in the blood of heart blood and brain of the victim was found to be 0.36 µg/mL and 1.20 µg/mL respectively, which was higher than the average value (0.041 µg/mL) found in the blood of 14 people who smoked.

• Journal of Animal Science and Technology
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• v.48 no.4
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• pp.575-586
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• 2006

This study was performed to determine potential antimicrobial activity of lactoferrin, which incorporated into the low-fat/salt sausages during storage either at 30 or 4℃. First, the model study on the antimicrobial activity of lactoferrin was performed. Based on the model study, more than 0.25% of lactoferrin was required to have a distinctive antimicrobial activity for the growth of E. coli O157:H7 in the broth. However, extended shelf-life was not shown in the low-fat/salt sausages manufactured with lactoferrin during refrigerated storage. In addition, no synergistic effects of lactoferrin with sodium lactate were observed in the sausages. These results indicated that the addition of lactoferrin into the low-fat sausages did not have antimicrobial activity of E. coli O157:H7, due to the denaturation of lactoferrin or the complexity of the sausage, even though it had a distinctive antimicrobial effect in the model study.

• Microbiology and Biotechnology Letters
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• v.4 no.3
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• pp.91-97
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• 1976

During the course of studies on the production and utilization of thermostable ${\alpha}$-amylase from a thormophilic actinomycete species isolated from soil, partial characterization of the ${\alpha}$-amylase has been (arried out. The optimum pH for the dextrinogenic activity of the enzyme was found to be 6.5 and the maximum reaction rate was achieved at a temperature range of 55$^{\circ}$ to 65$^{\circ}C$. Calcium ion was recognized to have a slight effect in activating the enzyme, while heavy metal salts especially ferrous and cupric ions showed a remarkable inhibition effect. The enzyme was best protected iron thermal denaturation at pH 8.0 with tris-HCI buffer；inactivation was rapid at higher or lower pH values. Furthermore, its thermal stability was greatly increased by calcium ion, particulary at the final concentration of 1${\times}$10$\^$－2/ mole in the reaction mixture. The Km value for the ${\alpha}$-amylase was calculated to be 2.17${\times}$10$\^$－4/g per $m\ell$ and the energy of activation for the dextrinogenic reaction to be 12,000${\pm}$580 ㎈ per mole.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.1
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• pp.55-61
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• 1997

In order to effectively utilize the fish and squid skin wastes derived from marine processing manufacture, the skin wastes of some pelagic fishes such as yellowfin sole, red cod, cod, Allaska pollack and flying squid were screened for the raw material of edible gelatin and studied some properties of those gelatins. The content of total collagen in the red cod skin was the highest (28.4 g/100 g wet skin), while that in the flying squid skin was the lowest (11.1 g/100 g wet skin) and those of another fishes were similar. Acid soluble collagens in the skins of the fishes and flying squid were $68.9\~84.8\%\;and\;44.3\%$, respectively. But showed no difference in the amino acid composition between acid soluble and insoluble collagens. Those collagens were consisted $\alpha\;and\;\beta$ chain and $\alpha$ chains extracted from fish skins except red cod and flying squid skins were hetero. The collagen of yellowfin sole skin exhibited slightly higher denaturation temperature $(25.4^{\circ}C)$ and also physical properties such as gel strength, melting point and gelling point were better than those of the other species.

• Food Science and Preservation
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• v.18 no.2
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• pp.208-211
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• 2011

Limonoids are abundant as bitter taste in citrus fruit and other plants. Interestingly. limonoid UDP-glucosyltransferase (LUGT) effectively ameliorates the bitterness from limonoid. The high level of LUGT expression in Escherichia coli can result in the formation of insoluble aggregates known as inclusion bodies. We isolated the soluble LUGT protein when this inclusion body was renaturated with ${\beta}$-cyclidextrin treatment after protein denaturation by urea. Our present results suggest that the isolation of LUGT from inclusion body in cells leads to shed light to characterize the enzyme for food industry purposes.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.957-963
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• 1999

Effects of cryoprotectants on protein denaturation of soybean curd, tofu, during frozen storage were examined. A whole-coagulated non-press tofu was prepared by adding 2% of isolated soybean protein to soy milk in order to prevent loss of added cryoprotectants. The cryoprotectants added were glocose, glycerol, sorbitol, propylene glycol, and tripolyphosphate. The texture characteristics of soybean curds before and after frozen storage were measured by sensory evaluation and Texture analyzer, and the results were evaluated by response surface methodology (RSM). Glucose, glycerol, sorbitol, and sodium tripolyphosphate were effective as single cryoprotectant, and the mixtures of glucose and sodium tripolyphosphate, and sorbitol and propylene glycol were also effective in minimizing textural change during freezing. Overall, the mixture of cryoprotectants were more effective than single cryoprotectant. According to the RSM, the maximum effect of cryoprotectants in minimizing textural changes during freezing was obtained with the mixture of 2.1% glucose, 6.7% glycerol, 2.1% sorbitol, 0.4% propylene glycol, and 0.3% sodium tripolyphosphate. However, considering the sensory acceptability, the optimum use of cryoprotectants in frozen tofu was 1% glucose, 2% glycerol, 1% sorbitol, 0.2% propylene glycol, and 0.5% sodium tripolyphosphate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.9
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• pp.1148-1153
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• 2008

For the effective use of red seabream, the texture between red seabream muscles cultured by feeding and starving were compared. Moisture and crude lipid contents of red seabream muscle cultured by starving (RCS) were 72.7% and 3.7%, respectively, which was 3% higher in the moisture compared to that of red seabream muscle cultured by feeding (RCF), while 3% lower in the crude lipid. The hardness of RCS was $0.93\;kg/cm^2$, which was higher than that ($0.47\;kg/cm^2$) of RCF. No differences in total collagen content, acetic acid-solublized collagen content, its thermal denaturation temperature and SDS-PAGE patterns between RCS and RCF were found. The results suggested that the difference in muscle texture between RCS and RCF was probably due to the difference of lipid content.

• BMB Reports
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• v.40 no.3
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• pp.315-324
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• 2007

The novel $\alpha$-amylase purified from locally isolated strain, Bacillus sp. KR-8104, (KRA) (Enzyme Microb Technol; 2005; 36: 666-671) is active in a wide range of pH. The enzyme maximum activity is at pH 4.0 and it retains 90% of activity at pH 3.5. The irreversible thermoinactivation patterns of KRA and the enzyme activity are not changed in the presence and absence of $Ca^{2+}$ and EDTA. Therefore, KRA acts as a $Ca^{2+}$-independent enzyme. Based on circular dichroism (CD) data from thermal unfolding of the enzyme recorded at 222 nm, addition of $Ca^{2+}$ and EDTA similar to its irreversible thermoinactivation, does not influence the thermal denaturation of the enzyme and its Tm. The amino acid sequence of KRA was obtained from the nucleotide sequencing of PCR products of encoding gene. The deduced amino acid sequence of the enzyme revealed a very high sequence homology to Bacillus amyloliquefaciens (BAA) (85% identity, 90% similarity) and Bacillus licheniformis $\alpha$-amylases (BLA) (81% identity, 88% similarity). To elucidate and understand these characteristics of the $\alpha$-amylase, a model of 3D structure of KRA was constructed using the crystal structure of the mutant of BLA as the platform and refined with a molecular dynamics (MD) simulation program. Interestingly enough, there is only one amino acid substitution for KRA in comparison with BLA and BAA in the region involved in the calcium-binding sites. On the other hand, there are many amino acid differences between BLA and KRA at the interface of A and B domains and around the metal triad and active site area. These alterations could have a role in stabilizing the native structure of the loop in the active site cleft and maintenance and stabilization of the putative metal triad-binding site. The amino acid differences at the active site cleft and around the catalytic residues might affect their pKa values and consequently shift its pH profile. In addition, the intrinsic fluorescence intensity of the enzyme at 350 nm does not show considerable change at pH 3.5-7.0.