• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.3
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• pp.232-237
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• 2009

Norovirus surrogate (feline calicivirus) was inactivated by treatment at 50,000 psi for 60 sec by 6.8-$log_{10}TCID_{50}mL^{-1}$. Tissue obtained from oyster (digestive gland, gill and mantle) was qualitatively destroyed and distorted by treatment at pressure greater than 5,000 psi for 60 sec. High pressure treatment induced progressive changes in the color of the oyster adductor muscle. High pressure treatment effectively reduced norovirus surrogate but induced conformational changes in the tissue and color of oyster flesh.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.5
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• pp.415-420
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• 2010

In Korea, oysters are used as an ingredient of Kimchi (Korean pickled cabbage) in early winter. Although viral contamination of oysters, including contamination by norovirus, can provoke gastroenteric illness, little is known of the epidemiological relationship to outbreaks. We postulated that Kimchi ripening can reduce the infectivity of norovirus, in order to test this hypothesis, we carried out a model experiment. Since norovirus is currently regarded as non-culturable, feline calicivirus (FCV) was used as a surrogate to examine the activation of norovirus with Kimchi ripening. In commercial well-prepared Kimchi, the infectivity ($TCID_{50}$) of FCV decreased by 2 log every 12 hours and reached the limit of detection after 48 hours during over-aging at $25^{\circ}C$. During storage at $4^{\circ}C$, the infectivity ($TCID_{50}$) of FCV decreased slowly and reached 5.00 $TCID_{50}$ after 48 hours. The low pH appears to affect the infectivity of FCV directly via organic acids produced by ripening during over-aging and storage. In neutralized lab-prepared Kimchi (pH 7.0), the infectivity ($TCID_{50}$) of FCV also decreased and reached the limit of detection after 72 hours at $4^{\circ}C$. This indicates that there are substances beside organic acids in Kimchi that originate from the raw materials and are produced during ripening. Among the raw materials, salt-fermented anchovies and garlic showed high direct antiviral activity. The main factor decreasing the infectivity of FCV in Kimchi was the high acidity caused by organic acids, regardless of the type, produced by ripening. Furthermore, unknown secondary products of microorganisms associated with Kimchi ripening and antiviral materials originating from raw material might contribute to the decreased infectivity of FCV, the surrogate of norovirus.

• Preventive Nutrition and Food Science
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• v.15 no.2
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• pp.130-136
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• 2010

Norovirus (NV) is becoming a major cause of foodborne illness in many countries. At present, very little is known about the survival of NV in the environment or the disinfection procedures needed to remove NV from contaminated surfaces. Feline calicivirus (FCV, $1{\times}10^{6.75}\;TCID_{50}/mL$) was used as a surrogate model for NV to investigate the effectiveness of sanitizing treatments for the viruses attached to food and food contact surfaces. Ammonium chloride (2%), organic acids (3000 ppm), and ethanol (70%) were most effective, providing $4\;log_{10}$ (99.99%) reductions in FCV titers on food or food contact surfaces. The disinfection efficacies of most agents on ceramic and glass surfaces were greater than stainless steel. The results from this study can be applied in the food industry to reduce NV-associated foodborne illnesses.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.925-930
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• 2008

Norovirus has become the most common cause of human gastroenteritis in developed countries. Detection procedures of foodborne viruses from foods require several steps. The concentration step using polyethylene glycol (PEG) is time-consuming and the detection efficiency of reverse transcription-polymerase chain reaction (RT-PCR) is affected by inhibitors from food components. In this study, a rapid detection method based on buoyant density centrifugation was developed to replace the time-consuming chloroform-polyethylene glycol-Tris Tween method. Feline calicivirus that belongs to the family Caliciviridae was used as a surrogate model for norovirus. After artificial inoculation of feline calcivirus (FCV) to oyster and lettuce, 830 ${\mu}L$ of homogenized sample suspension was layered on the top of 670 ${\mu}L$ 20% percoll and centrifuged. Then RNA extraction step was proceeded with the supernatant. By varying several physical conditions, the detection limits were lowered to $2.4{\times}10^2$ PFU per 1 g in oyster and $2.4{\times}10^0$ PFU per 1 g in lettuce. The protocol obtained in this study could be used to develop new detection method for norovirus in foods.

• Food Science and Industry
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• v.50 no.1
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• pp.67-73
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• 2017

Control of food pathogens is critical in food safety field. Norovirus is one of the major causes of gastroenteritis and food poisoning worldwide, however, currently, there is not a vaccine or a specific drug available for its treatment. There are several methods to inactivate norovirus during food processing by chemical and physical treatments, however, the use of natural substance has been suggested as an optional strategy due to their safety and consumer preference. In this study supported by Ministry of Food and Drug Safety in Korea, we identified novel plant-derived substances with significant anti-norovirus activities. The aim of this project was to determine the antiviral activity of a wide range of natural substances, including plant-derived extracts and essential oils, using a norovirus surrogate system, human norovirus replicon-bearing cells, and mouse in vivo experiments. During the activity screening test, we identified novel anti-norovirus substances or oils using plaque assay with MNV-1. Six selected substances were formulated into an optimum mixture and used as an ingredient for salad sauce of which anti-novovirus activity was confirmed(pending for patent and paper submission). The potential application of selected natural substances as a metal surface sanitizer was also tested. Interestingly, the mixture of selected natural compounds showed a significant inhibitory effect against norovirus. These results suggest that these substances may be used as food ingredient with anti-norovirus antivity or components for surface sanitizers to prevent norovirus contamination.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2106-2109
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• 2015

The synergy effect of trisodium phosphate (TSP) and ethanol against murine norovirus 1 (MNV-1), as a surrogate for human noroviruses, on fresh produces was evaluated. More than 2% (w/v) of TSP effectively inactivated MNV-1. The single treatment of 1% TSP or 30% ethanol for 30 min was not effective on MNV-1; however, cotreatment showed inactivation of MNV-1 on stainless steel and the produces of lettuce and bell pepper under 15 min. The results suggest that cotreatment of TSP and ethanol at a low concentration and a short time of exposure might be useful for the reduction of norovirus in some produce.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.3
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• pp.238-242
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• 2009

Recently coastal seawater has been contaminated by enteric viruses such as the norovirus via untreated groundwater globally. Accordingly, the consumption of molluscan shellfish from seawater that has been contaminated with fecal material has become an important issues. The levels of enteric viruses in seawater are low and recovery and concentration of the virus from large volumes of water is difficult. We compared the effectiveness of two representative method of concentrating virus using negatively and positively charged filters. The mean retention of seeded FCV by HAMF and NCCF was 48% and 78%, respectively. Overall, the recovery of NCCF was 43.3$\pm$11% better than that of HAMF. However, the eluate obtained by using beef extract solution in the NCCF procedure caused an inhibitory effect on the RT-PCR; therefore, it was necessary to employ a PCR inhibitor removal procedure. The HAMF eluate contained no PCR inhibitors, but HAMF was not an effective method of concentrating the virus from large volumes of natural seawater due to clogging.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.345-352
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• 2023

Antibacterial activity against foodborne bacteria (Bacillus cereus, Staphylococcus aureus, Salmonella Enteritidis) and inhibitory activity against murine norovirus, a human norovirus surrogate, of 28 extracts from plants endemic to Korea were investigated in this study. All plant extracts showed antibacterial activity only against gram-positive bacteria, B. cereus and S. aureus. Extracts from Callistemon speciosus and Nymphaea tetragona showed inhibition zones of 16.54 and 24.35 mm against B. cereus and S. aureus, respectively, presenting the highest antibacterial activities recorded in this study. Among all samples, Ardisia japonica extract at concentrations of 100 and 200 ㎍/mL showed the highest virucidal activities of 96.6 and 100.0%, respectively. Ardisia japonica, Duchesnea indica, Polygonum aviculare, and Geum japonicum extracts showed high antibacterial and virucidal activity simultaneously without Raw 264.7 cell cytotoxicity. These plant extracts may serve as potential antimicrobials to control foodborne infections.

• Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.155-158
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• 2014

The objective of this study was to evaluate the antiviral activity of Phaeophyta extracts against feline calicivirus (FCV), used as a norovirus surrogate. A bioassay-guided cytotoxicity and virus infectivity assay revealed that methanolic extracts of Phaeophyta possessed significant antiviral activity against FCV. Among them, Eisenia bicyclis extract exhibited the highest antiviral activity against FCV. The 50% effective concentration of the extract ($EC_{50}$) inhibiting FCV viral replication by 50% was $80{\mu}g/mL$. The extract also showed the highest selectivity index, calculated from the ratio of the median cellular cytotoxicity concentration ($CC_{50}$) and $EC_{50}$, indicating antiviral efficacy against FCV. In addition, significant interruption of FCV infection was observed by pretreatment of host Crandall-Reese feline kidney cells with the E. bicyclis extract ($200{\mu}g/mL$) prior to virus infection, in a dosedependent manner.

• Journal of Ginseng Research
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• v.35 no.4
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• pp.429-435
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• 2011

Korean red ginseng has been studied various biological activities such as immune, anti-oxidative, anti-microbial, and anticancer activities but antiviral mechanism needs further studies. In this study, we aimed to examine the antiviral effects of Korea red ginseng extract and ginsenosides on norovirus surrogate, including murine norovirus (MNV) and feline calicivirus (FCV). We evaluated the pre-, co-, and post-treatment effects of Korean red ginseng (KRG), ginsenosides $Rb_1$ and $Rg_1$. To measure the antiviral effect and cytotoxicity of KRG extract, and ginsenosides $Rb_1$ and $Rg_1$, we treated Crandell-Reese Feline Kidney for FCV or RAW264.7 cells for MNV with concentrations of 0, 5, 6.7, 10, 20 ug/mL total saponin. There was cytotoxic effect in the highest concentration 20 ug/mL of KRG extract so this concentration was excluded in this study. The FCV titer was significantly reduced to 0.23-0.83 $log_{10}$ 50% tissue culture infectious dose ($TCID_{50}$)/mL in groups pre-treated with red ginseng extract or ginsenosides. The titer of MNV was significantly reduced to 0.37-1.48 $log_{10}$ $TCID_{50}$/mL in groups pre-treated with red ginseng extract or ginsenosides. However, there was no observed antiviral effect in groups co-treated or post-treated with KRG and its constituents. Our data suggest that KRG extract has an antiviral effect against norovirus surrogates. The antiviral mechanisms of KRG and ginsenosides should be addressed in future studies.