• 대기
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• 제32권1호
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• pp.51-60
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• 2022

Corona Virus Disease 19 pandemic (COVID-19) causes many deaths worldwide, and has enormous impacts on society and economy. The COVID-19 was caused by a new type of coronavirus (Severe Acute Respiratory Syndrome Cornonavirus 2; SARS-CoV-2), which has been found that these viruses can be effectively inactivated by ultraviolet (UV) radiation of 290~315 nm. In this study, 90% inactivation time of the SARS-CoV-2 virus was analyzed using ground observation data from Brewer spectrophotometer at Yonsei University, Seoul and simulation data from UVSPEC for the period of 2015~2017 and 2020. Based on 12:00-13:00 noon time, the shortest virus inactivation time were estimated as 13.5 minutes in June and 4.8 minutes in July/August, respectively, under all sky and clear sky conditions. In the diurnal and seasonal variations, SARS-CoV-2 could be inactivated by 90% when exposed to UV radiation within 60 minutes from 10:00 to 14:00, for the period of spring to autumn. However, in winter season, the natural prevention effect was meaningless because the intensity of UV radiation weakened, and the time required for virus inactivation increased. The spread of infectious diseases such as COVID-19 is related to various and complex interactions of several variables, but the natural inactivation of viruses by UV radiation presented in this study, especially seasonal differences, need to be considered as major variables.

• 한국수산과학회지
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• 제52권6호
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• pp.644-649
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• 2019

Killed vaccines, developed by inactivation with formalin, have been investigated for many fish viruses. In this study, the inactivation of viral hemorrhagic septicemia virus (VHSV) by formalin was investigated based on the infectivity titer. When viral cell culture supernatants were used, the infectivity titer decreased 1,000-fold at 1 d after treatment with 0.1% (v/v) formalin, but was below the detection limit at 7 and 14 d. Moreover, neither the N nor G gene were detectable by RT-PCR immediately after formalin treatment. In western blot analysis, N protein was not detected by rabbit antiserum against VHSV KR-9225 from 2 d after formalin treatment. On the other hand, when we used a virus that was purified and concentrated ~100 times, the infectivity titer was maintained at 10^6.05 TCID₅₀/mL, even at 14 d after formalin treatment, and no change in the viral structural proteins was observed. This study provides important data on the production and use of formalin-inactivated vaccines.

• 한국연초학회지
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• 제18권2호
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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.

• Journal of Microbiology and Biotechnology
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• 제10권6호
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• pp.858-864
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• 2000

The purpose of the present study was to examine the efficacy and mechanism of the fraction IV cold ethanol fractionation and pasteurization ($60^{\circ}C$ heat treatment for 10h) steps, involved in the manufacture of albumin from human plasma, in the removal and/or inactivation of blood-born viruses. A variety of experimental model viruses for human pathogenic viruses, including the Bovine viral diarrhoea virus (BVDV), Bovine herpes virus (BHV), Murine encephalomyocarditis virus (EMCV), and Porcine parvovirus (PPV), were selected for this study. Samples from the relevant stages of the production process were spiked with the viruses, and the amount of virus in each fraction was then quantified using a 50% tissue culture infectious dose ($TCID_{50}$). The mechanism of reduction for the enveloped viruses (BHV and BVDV) during fraction IV fractionation was inactivation rather than partitioning, however, it was partitioning in the case of the non-enveloped viruses (EMCV and PPV). The log reduction factors achieved during fraction IV fractionation were ${\geq}6.9$ BHV, $\geq5.2$ for BBDV, 4.9 for EMC, and 4.0 for PPV. Pasteurization was found to be a robust and effective step in inactivating the enveloped viruses as well as EMCV. The log reduction factors achieved during pasteurization were $\geq7.0$ for BHV, $\geq6.1$ for BVDV, $\geq6.3$ for EMCV, and 1.7 for PPV. These results indicate that the production process for albumin has sufficient virus-reducing capacity to achieve a high margin for virus safety.

• 미생물학회지
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• 제39권4호
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• pp.242-247
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• 2003

Murine encephalomyocarditis virus (EMCV)는 혈장유래의약품의 바이러스 안전성 검증을 위해 hepatitis A virus (HAV)의 모델 바이러스로 사용되어왔다. 근래에 혈액응고인자제제에 의한 HAV 감염사례가 보고되면서 혈장유래의약품의 HAV 안전성 검증에 대한 국제적인 규제가 강화되어가고 있다. 본 연구에서는 HAV와 EMCV의 바이러스 불활화 공정에 대한 민감도를 평가하여, 혈장유래의약품 제조공정에서 HAV 불활화 공정의 검증법을 표준화하고자 하였다. HAV와 EMCV의 바이러스 불활화 공정에 대한 민감도를 평가한 결과 HAV가 60$^{\circ}C$ 열처리, low pH 처리(pH 3.9), 0.1 M NaOH 처리, 동결건조 공정 모두에서 EMCV보다 더 저항성이 큰 것을 확인할 수 있었다. EMCV는 특히 열처리와 0.1 NaOH 처리에 민감하게 불활화 되었지만, HAV는 큰 저항성을 나타내었다. 열처리의 경우 2시간 안에 EMCV는 검출한계 이하로 감소하였지만, HAV는 5시간 후에 검출한계 이하로 감소하였다. 0.1 M NaOH 처리시 EMCV는 15분 안에 검출한계 이하로 감소하였지만, HAV는 120분 정도의 처리에도 감염성 바이러스가 검출되었다. pH 3.9에서 25$^{\circ}C$로 14일 동안 항온하였을 때 HAV와 EMCV의 log 감소인수는 각각 1.63, 3.84이었다. 또한 혈액응고 8인자 제조공정의 동결건조 과정에서 HAV와 EMCV의 log 감소인수는 각각 1.21, 4.57이었다. 이와 같은 결과는 혈장유래의약품 제조공정의 HAV 불활화 또는 제거 검증시 모델 바이러스로 사용된 EMCV의 검증 결과를 해석함에 있어 보다 신중함을 가져야 한다는 것을 보여준다. 또한 보다 정확한 HAV검증 결과를 얻고자 한다면 모델 바이러스인 EMCV 보다 HAV를 사용하는 것이 보다 더 타당하다고 사료된다.

• 미생물학회지
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• 제18권3호
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• pp.123-132
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• 1980

Bacterial virus f2 and its RNA were examined to elucidate the mode of ozone utilizing sucrose density gradient analysis and electtron microscopic techniques. the inactivation kinetics of the virus f2 by ozonation showed that the viruses were inactivated during the first 5 sec of the reaction and were further inactivated at a slower rate during the next 10 min at 0.09 and 0.8mg/l ozone concentrations. The virus coat was broken by ozonation into many pieces of protein subunits and the adsorption of the viruses to the host pili was inversely related to the extent of the breakage of the virus. The viral RNA was released from the virus particles during ozone, but ozone inactivation of the RNA enclosed in the protein coat could not ruled out the possibility that the RNA was secondarily sheared by a reaction with the broken coat protein.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권1호
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• pp.65-68
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• 2004

The purpose of the present study was to examine the efficacy and mechanism of fraction IV cold ethanol fractionation and pasteurization (60$^{\circ}C$ heat treatment for 10 h), involved in the manufacture of albumin from human plasma, in the removal and/or inactivation of the hepatitis A virus (HAV). Samples from the relevant stages of the production process were spiked with HAV and the amount of virus in each fraction then quantified using a 50% tissue culture infectious dose (TCID$\_$50/). HAV was effectively partitioned from albumin during the fraction IV cold ethanol fractionation with a log reduction factor of 3.43. Pasteurization was also found to be a robust and effective step in inactivating HAV, where the titers were reduced from an initial titer of 7.60 log TCID$\_$50/ to undetectable levels within 5 h of treatment. The log reduction factor achieved during pasteurization was $\geq$4.76. Therefore, the current results indicate that the production process for albumin has sufficient HAV reducing capacity to achieve a high margin of virus safety.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.615-618
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• 2000

The purpose of present study was to examine the efficacy of PAB (para-amino benzamidine) affinity column chromatography, pasteurization ($60^{\circ}C$ heat treatment for 10 h), and lyophilization steps, employed in the manufacture of urokinase from human urine, in the removal and/or inactivation of urine-born viruses. Bovine herpes virus (BHV) and Murine encephalomyocarditis virus (EMCV) were selected for this study. Samples from the relevant stages of the production process were spiked with the viruses and the amount of virus in each fraction was quantified by 50% tissue culture infectious dose ($TCID_{50}$). BHV and EMCV were effectively partitioned from urokinase during PAB chromatography with the log reduction factors of 6.71 and 5.27, respectively. Pasteurization was a robust and effective step in inactivating BHV and EMCV, of which titers were reduced from initial titers of $8.65\;log_{10}\;TCID_{50}$ and $7.81\;log_{10}\;TCID_{50}$, respectively, to undetectable levels within 1 hour of treatment. The log reduction factors achieved during lyophilization were 2.06 for BHV and 4.54 for EMCV. These results indicate that the production process for urokinase has sufficient virus reducing capacity to achieve a high margin of virus safety.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권6호
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• pp.340-346
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• 2002

The purpose of the present study was to examine the efficacy and mechanism of the PAB (para-amino benzamidine) affinity column chromatography, Viresolve NFP virus filtration, pasteurization (60$\^{C}$ heat treatment for 10 h), and lyophilization steps employed in the manufacture of urokinase from human urine as regards the removal and/or inactivation of the hepatitis A virus (HAV). Samples from the relevant stages of the production process were spiked with HAV and subjected to scale-down processes mimicking the manufacture of urokinase Samples were collected at each step, immediately titrated using a 50% tissue culture infectious dose (TCID$\_$50/), and the virus reduction factors evaluated. PAB chromatography was found to be an effective step for removing HAV with a log reduction factor of 3.24. HAV infectivity was rarely detected in the urokinase fraction, while most of the HAV infectivity was recovered in the unbound and wash fractions. HAV was completely removed during the Viresolve NFP filtration with a log reduction factor of $\geq$ 4.60. Pasteurization was also found to be an effective step in inactivating HAV where the titers were reduced from an initial titer of 7.18 log$\_$10/ TCID$\_$50/ to undetectable levels within 10 h of treatment. The log reduction factor achieved during pasteurization was $\geq$ 4.76. Lyophilization revealed the lowest efficacy for inactivating HAV with a log reduction factor of 1.48. The cumulative log reduction factor was $\geq$ 14.08. Accordingly, these results indicate that the production process for urokinase exhibited a sufficient HAV reducing capacity to achieve a high margin of virus safety.

• Journal of Microbiology
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• 제38권3호
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• pp.187-191
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• 2000

A validation study was conducted to determine the efficacy of solvent/Detergent (S/D) inactivation and Q-Sepharose column chromatographic removal of the human immunodeficiency virus (HIV) during the manufacturing of a high purity antihemopilic factor VIII (GreenMono) from human plasma. S/D treatment using the organic solvent, tri (n-butyl) phosphate, and the detergent, Trition X-100, was a robust and effective step in eliminating HIV-1. The HIV-1 titer was reduced from an initial titer of 8.3 log10 TCID50 to undetectable levels within one minute of S/D treatment, HIV-1 was effectively partitioned form factor VIII during Q-Sepharose column chromatography with the log reduction factor of 4.1 . These results strongly assure the safety of GreenMono From HIV.