• The Korean Journal of Zoology
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• v.32 no.2
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• pp.134-141
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• 1989

The present investigation aims at elucidating a possible mechanism of heat inactivation of SCK ceils by comparing the kinetics of cell lethality and protein degradation in the presence of heat protector or heat sensitizer. The effect of heat sensitizer and protector was exhibited in both cell survival and protein degradation kinetics, the magnitude of the effect being much profound for the protector compared to the sensitizer. A conclusion to he drawn from the present experiment is that there is no direct correlation between cell lethality and protein degradation. Rather, protein degradation, which might occur in the membrane, causes cell inactivation indirectly, possibly by altering the cellular environment. Accordingly, further studies are needed to get insight into the mechanism of cell inactivation by hyperthermia.

• Journal of Ginseng Research
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• v.7 no.1
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• pp.88-93
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• 1983

Studies were carried out to elucidate the protein stabilizing effect of ginseng. Malate dehydrogenase (EC 1.1.1.37) was used as a protein and the rate constant of the enzyme inactivation was determined under the heat denaturation condition. There was an optimum pH for the enzyme stability, the rate constant of the enzyme inactivation was minimum at BH 8.8. The rate constant was increased at lower and higher pH regions than the optimum pH. The inactivation reaction followed the Arrehnius law and the activation energy was measured as 36.8kcal/mole. The reaction rate was not affected by the enzyme concentration and thus it was assumed to be unimolecular first order reaction. The water extract of red ginseng decreased the rate constant of Malate dehydrogenate under heat inactivation condition to stabilize the enzyme activity. Purified ginseng saponin also stabilized the enzyme against heat inactivation.

• Archives of Pharmacal Research
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• v.21 no.5
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• pp.543-548
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• 1998

We examined the immunological properties of the recombinant hepatitis B surface antigen (r-HBsAg) which was expressed in mammalian cell (C127). The cross-immunity of r-HBsAg and plasma-derived hepatitis B surface antigen (p-HBsAg) were tested using Western blotting and ELISA with guinea pig polyclonal antibody and naturally infected human-derived antibody and the both antigens show the same results in their response pattern and intensity, which indicate they have a good cross-immunity. from the measurement of $ED_{50}$ after formalin- or heat-inactivation, both r-HBsAg and p-HBsAg and p-HBsAg showed $ED_{50}$ of 0.2-0.3 in formalin-inactivaton, while r-HBsAg was 0.05-0.09 and p-HBsAg was 0.03-0.07 in heat-inactivation, which means heat-inactivation method is 3-4 times superior in immunogenicity. In the immunopersistency test performed in guinea pig for the period of 3 months with two different adjuvants, antibody titer was 34.2 with muramyl dipeptide adjuvant, which was 1.8 times greater than the antibody titer of 18.9 with $AIPO_{4}$ adjuvant. the mutagenicity of r-HBsAg has the same cross-immunity with p-HBsAg, and heat-inactivation method and muramyl dipeptide adjuvant allow development of r-HBsAg vaccine with excellent immunogenicity.

• The Korean Journal of Zoology
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• v.32 no.4
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• pp.305-313
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• 1989

The present investigation aims at inquiring into a possible target for the heat inactivation of SCK tumor cells by comparing the kinetics of cell survival, rate of protein synthesis, and DNA polymerase activity in the presence of heat protector or heat sensitirer. A possible conclusion to be drawn from the present experiment is that there is no direct correlation between cell death and decrease in the rate of protein synthesis, but that the loss of DNA polvmerase $\beta$ activity correlates quite well with cell inactivation. Thus, protein degrada-tion and/or abnormal protein synthesis causes cell inactivation innireuv, possibly by altering the cellular environment which in turn affects the DNA polymerase $\beta$ activity. Accordingly, further studies, dealing with the correlation between changes in the cellular environment and DNA polymerase $\beta$ activity, are needed to set insight into a possible target for the heat inactivation of cells. 본 연구는 열보호제 또는 열증감제의 존재하에서 세포 생존곡선, 단백질 합성률, DNA 중합효소 $\beta$의 활성변화를 비교 검토함으로써 SCK 종양세포가 열에 의해서 불활성화될 때의 표적이 무엇인지를 밝혀보기 위해서 수행되었다. 본 실험의 결과로 추정하건대 열에 의한 세포치사는 단백질 합성률의 변화와는 직접적인 연관성이 없으나, DNA 중합효소 $\beta$의 활성도와는 밀접한 연관성이 있음을 알 수 있다. 즉, 단백질의 분해 또는 비정상적인 단백질의 합성이 세포의 환경을 변화시키고 이것이 DNA 중합효소 $\beta$의 활성에 영향을 미침으로써 간접적으로 세포의 치사를 초래할 것으로 짐작할 수 있다. 따라서, 세포의 열불화성화의 표적을 좀더 분명히 밝히기 위해서는 세포의 환경변화와 DNA 중합효소 $\beta$의 활성과의 관계를 추구하는 연구가 수행되어야 할 것으로 사료된다.

• Korean Journal of Veterinary Research
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• v.11 no.2
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• pp.137-140
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• 1971

Survival and thermal inactivation after heat treatment at $143^{\circ}F$ were observed among 27 strains of coliform bacteria isolated from dairy cattle. The results obtained were as follows. 1. The obvious differences in heat-sensitivity were observed among the strains tested. 2. No strain was found resistant to the heat treatment of $143^{\circ}F$ for 30 minutes. 3. A marked effect of density of coliform bacteria on the survival after the heat treatment was observed. As the density of coliform bacteria was increased, the rate of survival was increased markedly regardless of the length of heat treatment.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.603-607
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• 2008

Thirteen commercial antimicrobial products were examined to assess the sporicidal activity against Bacillus cereus spores at room temperature, 60 and $85^{\circ}C$. Neither the antimicrobials showed detectable antimicrobial activity against the B. cereus spores nor induced spore germination after the treatment at 0.5 or 1.0%(w/v, v/v) commercial antimicrobial agents at room temperature for 0.5 to 4 hr. However, when the antimicrobials such as chitosan, lactic acid, fermented pollen, grapefruit extract were applied with heat at $85^{\circ}C$ for 30 min, more than 1 log CFU/mL spores were additionally inactivated compared to only heat treatment without antimicrobials. Imposition of $60^{\circ}C$ to B. cereus spores with the higher concentration of 5.0%(v/v) lactic acid or 2.5%(w/v) thiamine dilaurylsulfate for the longer time incubation of 24 hr resulted in 3 log CFU/mL spore inactivation. This work showed that low concentrations of commercial antimicrobials by themselves did not inactivate B. cereus spores. However, when physical processes such as heat were combined together, antimicrobials showed a synergistic effect against B. cereus spores.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.2
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• pp.99-102
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• 1989

The level of serum alkaline phosphatase activity was determined in 7 Japanese Black steers at different ages. The isoenzyme activity of non-bone origin was estimated using a heat-inactivation technique. The activity of serum alkaline phosphatase (SALP, K-A unit) decreased as age (AGE, mo.) increased: SALP = 14.15 - 0.17 (${\pm}\;0.03$) AGE, r = -0.81, P<0.01, $S.E.\;{\pm}\;0.28$. The variation of the activity was greater in younger age than the older. The temperature of $58^{\circ}C$ for the treatment of heat inactivation of bovine serum appeared to be suitable. The percentage of heat inactivated enzyme activity negatively correlated with age and positively with the level of serum alkaline phosphatase activity. The activity of SALP of non-bone origin was inferred to stay at about constant level irrespective of age and that of bone origin decreased with age.

• Archives of Pharmacal Research
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• v.5 no.2
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• pp.45-52
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• 1982

Staibilization effect of Panax ginseng C. A. Meyer on .betha.-D-Galactosidase inactivation was proved by kinetic studies of thermal inactivation of the enzyme. The water extract Panax ginseng C. A. Meyer showed stabilization activity at minimal concentration of 10ppm. The methanolic extract was purified to obtain ginseng saponins, and two groups of the ginsenosides, i. e. protopanaxadiol and protopanaxatriol were isolated. They also showed a protective effect against the thermal and chemical inactivation of the enzyme; p-chloromercuribenzoic acid and hydroxylamine known as protein modifier greatly inactivated the enzyme but inactivation was significantly balocked by the ginseng component MG$^{2+}$, known as a cofactor, stabilized the enzyme and the poor stabilization effect by it was potentiated by ginseng components.s.

• Journal of the Korean Society of Tobacco Science
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• v.18 no.2
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• pp.120-125
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• 1996

Dried tobacco leaf debris infected with tobacco mosaic virus (TMV) was subjected to heat treatment (6$0^{\circ}C$~10$0^{\circ}C$) with or without addition of moisture and to room temperature for natural decay to examine the periods of time required for the inactivation of PMV in the inoculum source. Wet conditions (60% moisture content of the debris) for heat treatment were more efficient than dry conditions to inactivate the virus at 7$0^{\circ}C$~10$0^{\circ}C$, and which decrease of temperature, the time needed for the viral inactivation increased greatly. At 6$0^{\circ}C$ and 7$0^{\circ}C$, the temperaturein a compost heap during the actively decomposing period, it takes about 15 days or more for the complete inactivation of the virus. However, considering the decrease of the viral infectivity during the decomposition, a shorter period of time will be required to inactivate TMV in the conditions mentioned above, suggesting that a well decomposed organic manure containing tobacco leaf debris may not have infective TMV and may not provide a potential inoculum source.

• Food Science of Animal Resources
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• v.33 no.3
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• pp.317-324
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• 2013

Radio-frequency driven atmospheric pressure plasma using argon gas was studied in the inactivation of Campylobacter jejuni in order to investigate its applicability. First, the inactivation study was conducted on an agar surface. C. jejuni NCTC11168 was reduced by more than 7 Log CFU after an 88 s treatment. Another strain, ATCC49943, was studied; however, the inactivation was less efficient, with a 5 Log CFU reduction after a 2 min treatment. Then, chicken breast ham was studied at the $10^6$ CFU inoculation level. The inactivation efficiency was much lower for both strains compared to that on the agar plates. C. jejuni NCTC11168 and ATCC49943 were reduced by 3 Log CFU after a 6 min treatment and by 1.5 Log CFU after a 10 min treatment, respectively. The scanning electron microscopy analysis indicated that C. jejuni cells were deformed or transformed into coccoid form under the plasma treatment. During the plasma treatment, the temperature of the samples did not rise above $43^{\circ}C$, suggesting that heat did not contribute to the inactivation. Meanwhile, water activity significantly decreased after a 10 min treatment (p<0.05). This study conveyed that radio-frequency atmospheric pressure plasma can effectively inactivate C. jejuni with strain-specific variation.