scholarly journals Antiviral Effects of Lindera obtusiloba Leaf Extract on Murine Norovirus-1 (MNV-1), a Human Norovirus Surrogate, and Potential Application to Model Foods

Antibiotics ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 697
Author(s):  
Diana Solis-Sanchez ◽  
Adriana Rivera-Piza ◽  
Soyoung Lee ◽  
Jia Kim ◽  
Bomi Kim ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Leaf Extract ◽  
Food Poisoning ◽  
Inhibitory Effect ◽  
Viral Infectivity ◽  
Murine Norovirus ◽  
Inhibitory Effects ◽  
Human Norovirus ◽  
Lindera Obtusiloba ◽  
Natural Agent

Noroviruses are the leading cause of acute gastroenteritis and food poisoning worldwide. In this study, we investigated the anti-noroviral activity of Lindera obtusiloba leaf extract (LOLE) using murine norovirus (MNV-1), a surrogate of human norovirus. Preincubation of MNV-1 with LOLE at 4, 8, or 12 mg/mL for 1 h at 25 °C significantly reduced viral infectivity, by 51.8%, 64.1%, and 71.2%, respectively. Among LOLE single compounds, β-pinene (49.7%), α-phellandrene (26.2%), and (+)-limonene (17.0%) demonstrated significant inhibitory effects on viral infectivity after pretreatment with MNV-1, suggesting that the anti-noroviral effects of LOLE may be due to the synergetic activity of several compounds, with β-pinene as a key molecule. The inhibitory effect of LOLE was tested on the edible surfaces of lettuce, cabbage, and oysters, as well as on stainless steel. After one hour of incubation at 25°C, LOLE (12 mg/mL) pretreatment significantly reduced MNV-1 plaque formation on lettuce (76.4%), cabbage (60.0%), oyster (38.2%), and stainless-steel (62.8%). These results suggest that LOLE effectively inhibits norovirus on food and metal surfaces. In summary, LOLE, including β-pinene, may inactivate norovirus and could be used as a natural agent promoting food safety and hygiene.

Comparing Human Norovirus Surrogates: Murine Norovirus and Tulane Virus

2013 ◽  
Vol 76 (1) ◽  
pp. 139-143 ◽  
Author(s):  
KIRSTEN A. HIRNEISEN ◽  
KALMIA E. KNIEL
Keyword(s):  
Tap Water ◽  
Plaque Assay ◽  
Heat Treatments ◽  
Viral Infectivity ◽  
Murine Norovirus ◽  
Human Norovirus ◽  
Human Noroviruses ◽  
Ph Values ◽  
Significant Difference ◽  
Tulane Virus

Viral surrogates are widely used by researchers to predict human norovirus behavior. Murine norovirus (MNV) is currently accepted as the best surrogate and is assumed to mimic the survival and inactivation of human noroviruses. Recently, a new calicivirus, the Tulane virus (TV), was discovered, and its potential as a human norovirus surrogate is being explored. This study aimed to compare the behavior of the two potential surrogates under varying treatments of pH (2.0 to 10.0), chlorine (0.2 to 2,000 ppm), heat (50 to 75°C), and survival in tap water at room (20°C) and refrigeration (4°C) temperatures for up to 30 days. Viral infectivity was determined by the plaque assay for both MNV and TV. There was no significant difference between the inactivation of MNV and TV in all heat treatments, and for both MNV and TV survival in tap water at 20°C over 30 days. At 4°C, MNV remained infectious over 30 days at a titer of approximately 5 log PFU/ml, whereas TV titers decreased significantly by 5 days. MNV was more pH stable, as TV titers were reduced significantly at pH 2.0, 9.0, and 10.0, as compared with pH 7.0, whereas MNV titers were only significantly reduced at pH 10.0. After chlorine treatment, there was no significant difference in virus with the exception of at 2 ppm, where TV decreased significantly compared with MNV. Compared with TV, MNV is likely a better surrogate for human noroviruses, as MNV persisted over a wider range of pH values, at 2 ppm of chlorine, and without a loss of titer at 4°C.

scholarly journals The Enterovirus Protease Inhibitor Rupintrivir Exerts Cross-Genotypic Anti-Norovirus Activity and Clears Cells from the Norovirus Replicon

2014 ◽  
Vol 58 (8) ◽  
pp. 4675-4681 ◽  
Author(s):  
J. Rocha-Pereira ◽  
M. S. J. Nascimento ◽  
Q. Ma ◽  
R. Hilgenfeld ◽  
J. Neyts ◽  
...  
Keyword(s):  
Protease Inhibitor ◽  
Antiviral Effect ◽  
Inhibitory Effect ◽  
Murine Norovirus ◽  
Norwalk Virus ◽  
Rna Dependent Rna Polymerase ◽  
Human Norovirus ◽  
Polymerase Inhibitors ◽  
Murine Noroviruses

ABSTRACTPotent and safe inhibitors of norovirus replication are needed for the treatment and prophylaxis of norovirus infections. We here report that thein vitroanti-norovirus activity of the protease inhibitor rupintrivir is extended to murine noroviruses and that rupintrivir clears human cells from their Norwalk replicon after only two passages of antiviral pressure. In addition, we demonstrate that rupintrivir inhibits the human norovirus (genogroup II [GII]) protease and further explain the inhibitory effect of the molecule by means of molecular modeling on the basis of the crystal structure of the Norwalk virus protease. The combination of rupintrivir with the RNA-dependent RNA polymerase inhibitors 2′-C-methylcytidine and favipiravir (T-705) resulted in a merely additive antiviral effect. The fact that rupintrivir is active against noroviruses belonging to genogroup I (Norwalk virus), genogroup V (murine norovirus), and the recombinant 3C-like protease of a GII norovirus suggests that the drug exerts cross-genotypic anti-norovirus activity and will thus most likely be effective against the clinically relevant human norovirus strains. The design of antiviral molecules targeting the norovirus protease could be a valuable approach for the treatment and/or prophylaxis of norovirus infections.

Evaluation of Murine Norovirus Persistence in Environments Relevant to Food Production and Processing

2011 ◽  
Vol 74 (11) ◽  
pp. 1847-1851 ◽  
Author(s):  
S. FALLAHI ◽  
K. MATTISON
Keyword(s):  
Stainless Steel ◽  
Food Production ◽  
Room Temperature ◽  
Potable Water ◽  
Plaque Assay ◽  
The Other ◽  
Murine Norovirus ◽  
Human Norovirus ◽  
Log Reduction ◽  
Virus Survival

Human norovirus (NoV) causes outbreaks of acute gastroenteritis associated with many ready-to-eat foods, including fresh produce. Effective inactivation procedures must consider virus survival under conditions of produce production and processing. This study aimed to investigate the persistence of NoV in a variety of environments, using murine NoV (MNV) as a surrogate for NoV. MNV was incubated for up to 42 days at room temperature on stainless steel disks, on lettuce, on soil, and in potable water and titers determined by plaque assay. A 1-log reduction of MNV infectivity was observed after 29 days in water, 4 days on lettuce, 12 days on soil, and 15 days on stainless steel disks. MNV survived longer in water than in any of the other environments, indicating that drying may contribute to NoV inactivation. MNV genomes were not significantly reduced for up to 42 days, suggesting that genomic detection is not a reliable indicator of viability. Overall, our findings provide valuable information regarding the potential for NoV transmission in the food supply.

scholarly journals Inhibitory Effects of Bryophyllum pinnatum Leaf Extract on Inflammatory Biomarkers

2021 ◽  
pp. 7-13
Author(s):  
Adebayo Afees Oladejo ◽  
Onwubuya Emmanuel Ikechuckwu ◽  
Ogbunugafor Henrietta Aritetsoma ◽  
Okafor Chike Samuel ◽  
Ogbodo Chibuzor Uche
Keyword(s):  
Leaf Extract ◽  
Inhibitory Effect ◽  
Inflammatory Biomarkers ◽  
Dependent Manner ◽  
Inhibitory Effects ◽  
Dose Dependent ◽  
Rich Content ◽  
Traditional Medical Practice ◽  
India And China ◽  
Bryophyllum Pinnatum

Bryophyllum pinnatum Lam. (Crassulaceae) called ‘Oda-opue’ in Igbo and ‘Abamoda’ in Yoruba are widely used as food and as medicines in traditional medical practice. They are found widely in tropical Africa, America, India and China. This study investigated the inhibitory effect of the hydro-ethanol leaf extract on inflammatory biomarkers. The Cotton Pellet Induced Granuloma method was used in the study. The plant extract significantly inhibited the inflammatory biomarkers, cyclooxygenases 1 and 2, interleukins 1β and 6, and prostaglandin E2, in a dose dependent manner indicating a reduction of inflammation in the rats. The study showed that B. pinnatum leaf extract possess a rich content of bioactive compounds which could be synthesized to produce new plant-based product to fight inflammatory disorders with fewer side effects.

Tenacity of Human Norovirus and the Surrogates Feline Calicivirus and Murine Norovirus during Long-Term Storage on Common Nonporous Food Contact Surfaces

2015 ◽  
Vol 78 (1) ◽  
pp. 224-229 ◽  
Author(s):  
SASCHA MORMANN ◽  
CATHRIN HEIßENBERG ◽  
JENS PFANNEBECKER ◽  
BARBARA BECKER
Keyword(s):  
Stainless Steel ◽  
Real Time ◽  
Room Temperature ◽  
Plaque Assay ◽  
Feline Calicivirus ◽  
Murine Norovirus ◽  
Rt Pcr ◽  
Human Norovirus ◽  
Food Contact Surfaces ◽  
Contact Surfaces

The transfer of human norovirus (hNV) to food via contaminated surfaces is highly probable during food production, processing, and preparation. In this study, the tenacity of hNV and its cultivable surrogates feline calicivirus (FCV) and murine norovirus (MNV) on two common nonporous surface materials at two storage temperatures was directly compared. Virus titer reduction on artificially inoculated stainless steel and plastic carriers was monitored for 70 days at room temperature and at 7°C. Viruses were recovered at various time points by elution. Genomes from intact capsids (hNV, FCV, and MNV) were quantified with real-time reverse transcription (RT) PCR, and infectivity (FCV and MNV) was assessed with plaque assay. RNase treatment before RNA extraction was used to eliminate exposed RNA and to assess capsid integrity. No significant differences in titer reduction were found between materials (stainless steel or plastic) with the plaque assay or the real-time quantitative RT-PCR. At room temperature, infectious FCV and MNV were detected for 7 days. Titers of intact hNV, FCV, and MNV capsids dropped gradually and were still detectable after 70 days with a loss of 3 to 4 log units. At 7°C, the viruses were considerably more stable than they were at room temperature. Although only MNV infectivity was unchanged after 70 days, the numbers of intact capsids (hNV, FCV, and MNV) were stable with less than a 1-log reduction. The results indicate that hNV persists on food contact surfaces and seems to remain infective for weeks. MNV appears to be more stable than FCV at 7°C, and thus is the most suitable surrogate for hNV under dry conditions. Although a perfect quantitative correlation between intact capsids and infective particles was not obtained, real-time quantitative RT-PCR provided qualitative data about hNV inactivation characteristics. The results of this comparative study might support future efforts in assessment of foodborne virus risk and food safety.

Polymerized Degradable Hyaluronan – a Platform for Stent Coating with Inherent Inhibitory Effects on Neointimal Formation in a Porcine Coronary Model

2002 ◽  
Vol 25 (12) ◽  
pp. 1166-1173 ◽  
Author(s):  
B. Heublein ◽  
E.G. Evagorou ◽  
R. Rohde ◽  
S. Ohse ◽  
R.R. Meliss ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Inhibitory Effect ◽  
Local Drug Delivery ◽  
Inhibitory Effects ◽  
Neointimal Formation ◽  
Ha Coating ◽  
Pig Coronary Arteries ◽  
Stent Coating ◽  
Wall Injury

Biodegradable hyaluronan (hyaluronic acid, HA) made insoluble by self-cross-linking in the presence of N-(3-dimethylaminopropyl)-N′-ethyl carbodiimide (EDC) has been used to cover stents. The maximum polymer-mass on a 16-mm stainless steel stent is approximately 2 mg. During manual crimping and simulated application, the loss of polymerized HA is negligible. The insoluble HA coating has an advantageous inherent antiproliferative effect regarding neointimal formation after local vessel wall injury (overstretch model) and leads to a reduced inflammatory response compared to uncoated stainless-steel stents, used as control, in undiseased pig coronary arteries, over a follow-up period of four weeks. Thus, cross-linked HA stent coating warrants further research as an interactive degradable biomaterial with an inherent inhibitory effect on neointimal formation as a possible biomatrix for local drug delivery to reduce restenosis rate.

The effects of Triplochiton scleroxylon aqueous extracts on initial growth of some vegetable crops in Ghana

2018 ◽  
Vol 1 (2) ◽  
pp. 93-97
Author(s):  
S. Abugre
Keyword(s):  
Leaf Extract ◽  
Inhibitory Effect ◽  
Initial Growth ◽  
Aqueous Extracts ◽  
Vegetable Crops ◽  
Inhibitory Effects ◽  
Pathology Laboratory ◽  
Root Extracts ◽  
Randomized Design ◽  
Completely Randomized Design

The effect of Triplochiton scleroxylon (wawa) aqueousextracts were tested on the seeds of tomato (Lycopersicumesculentum), pepper (Capsicum annuum ) and garden egg (Solanummelongena ) in the pathology laboratory of the Forestry Research Institute of Ghana (FORIG). Aqueous extracts of T. scleroxylon leaves (L) and roots (R) were prepared at different concentrations of 2%, 4%, 6%, and 8% and applied to the seeds. The effects of these treatments were assessed in a Completely Randomized Design (CRD) with 4 replications. The findings showed that all the vegetable crops were affected by the different concentrations of the leaf and roots aqueous extracts (P<0.05). Tukey-Kramer multiple comparison indicated that the inhibitory effect was positively correlated with concentration of the extracts. The higher extract concentrations (6%-8%) had stronger inhibitory effect whereas; in some cases the lower concentration (2%-4%) showed stimulatory effect during germination. The radicles were more susceptible to the effect of the extracts than the plumules. The germination of L.esculentum was highly inhibited in growth by 51.4% in both the leaf and root extracts. Similarly, C.annuum recorded the highest inhibitory effect on radicle length by 72.5% in the leaf extract whilst, the highest inhibitory effects in plumule was 44%. The overall results point to an allelopathic inhibitory effect of T. scleroxylon on the three vegetable crops.

scholarly journals Destruction of the Capsid and Genome of GII.4 Human Norovirus Occurs during Exposure to Metal Alloys Containing Copper

2015 ◽  
Vol 81 (15) ◽  
pp. 4940-4946 ◽  
Author(s):  
C. S. Manuel ◽  
M. D. Moore ◽  
L. A. Jaykus
Keyword(s):  
Stainless Steel ◽  
Copy Number ◽  
Copper Alloys ◽  
Pure Copper ◽  
Protein Band ◽  
Murine Norovirus ◽  
Human Norovirus ◽  
Copper Surfaces ◽  
Public Health Burden ◽  
Rnase Treatment

ABSTRACTHuman norovirus (HuNoV) represents a significant public health burden worldwide and can be environmentally transmitted. Copper surfaces have been shown to inactivate the cultivable surrogate murine norovirus, but no such data exist for HuNoV. The purpose of this study was to characterize the destruction of GII.4 HuNoV and virus-like particles (VLPs) during exposure to copper alloy surfaces. Fecal suspensions positive for a GII.4 HuNoV outbreak strain or GII.4 VLPs were exposed to copper alloys or stainless steel for 0 to 240 min and recovered by elution. HuNoV genome integrity was assessed by reverse transcription-quantitative PCR (RT-qPCR) (without RNase treatment), and capsid integrity was assessed by RT-qPCR (with RNase treatment), transmission electron microscopy (TEM), SDS-PAGE/Western blot analysis, and a histo-blood group antigen (HBGA) binding assay. Exposure of fecal suspensions to pure copper for 60 min reduced the GII.4 HuNoV RNA copy number by ∼3 log10units when analyzed by RT-qPCR without RNase treatment and by 4 log10units when a prior RNase treatment was used. The rate of reduction of the HuNoV RNA copy number was approximately proportional to the percentage of copper in each alloy. Exposure of GII.4 HuNoV VLPs to pure-copper surfaces resulted in noticeable aggregation and destruction within 240 min, an 80% reduction in the VP1 major capsid protein band intensity in 15 min, and a near-complete loss of HBGA receptor binding within 8 min. In all experiments, HuNoV remained stable on stainless steel. These results suggest that copper surfaces destroy HuNoV and may be useful in preventing environmental transmission of the virus in at-risk settings.

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