Lack of Correlation between Virus Barosensitivity and the Presence of a Viral Envelope during Inactivation of Human Rotavirus, Vesicular Stomatitis Virus, and Avian Metapneumovirus by High-Pressure Processing

Abstract

High-pressure processing (HPP) is a nonthermal technology that has been shown to effectively inactivate a wide range of microorganisms. However, the effectiveness of HPP on inactivation of viruses is relatively less well understood. We systematically investigated the effects of intrinsic (pH) and processing (pressure, time, and temperature) parameters on the pressure inactivation of a nonenveloped virus (human rotavirus [HRV]) and two enveloped viruses (vesicular stomatitis virus [VSV] and avian metapneumovirus [aMPV]). We demonstrated that HPP can efficiently inactivate all tested viruses under optimal conditions, although the pressure susceptibilities and the roles of temperature and pH substantially varied among these viruses regardless of the presence of a viral envelope. We found that VSV was much more stable than most food-borne viruses, whereas aMPV was highly susceptible to HPP. When viruses were held for 2 min under 350 MPa at 4°C, 1.1-log, 3.9-log, and 5.0-log virus reductions were achieved for VSV, HRV, and aMPV, respectively. Both VSV and aMPV were more susceptible to HPP at higher temperature and lower pH. In contrast, HRV was more easily inactivated at higher pH, although temperature did not have a significant impact on inactivation. Furthermore, we demonstrated that the damage of virion structure by disruption of the viral envelope and/or capsid is the primary mechanism underlying HPP-induced viral inactivation. In addition, VSV glycoprotein remained antigenic although VSV was completely inactivated. Taken together, our findings suggest that HPP is a promising technology to eliminate viral contaminants in high-risk foods, water, and other fomites.High-pressure processing (HPP) is a nonthermal pasteurization technology that uses pressure instead of thermal energy to inactivate harmful pathogens. In the food industry, HPP has been used to inactivate food-borne infectious agents (such as bacteria, viruses, fungi, protozoa, and prions) and proteins (such as enzymes, allergens, and toxins) (2, 3, 6, 9). The primary advantage of HPP is that it has minimal effect on the organoleptic and nutritional properties of foods compared to other processing methods, since the treatment does not disrupt the covalent bonds stabilizing the structure of micronutrients as well as color and flavor compounds (3,5,23,39). In addition, since pressure acts instantaneously and uniformly throughout the pressure vessel, the structure and texture of many high-moisture foods are minimally affected. In today's modern society, consumers are increasingly demanding food products that are minimally processed and free of preservatives. Thus, HPP is becoming a widely used nonthermal processing technology that can ensure food safety, food quality, shelf-life extension, and nutritional value.Despite the extensive research on the inactivation of bacterial pathogens by HPP, the inactivation of viruses by HPP is less well understood. With regard to applications in the area of food safety, HPP studies have focused on food-and waterborne virus...

High-Pressure Inactivation of Rotaviruses: Role of Treatment Temperature and Strain Diversity in Virus Inactivation

“…Interestingly, HPP inactivation of the Wa strain was not significantly impacted by the initial temperature during treatment in culture medium or oyster tissues. This is consistent with our previous observation of an approximately a 5-log virus reduction for the Wa strain under 400 MPa at either 4 or 20°C (27). Overall, our results suggest that a low initial temperature increases the inactivation of a majority of the RV strains by HPP.…”

“…RV plaque assay was performed as described previously (27). Briefly, monolayers of MA-104 cells were grown in six-well plates (Corning Life Sciences, Wilkes-Barre, PA) at a density of 2 ϫ 10 6 cells per well.…”

“…Temperature is a critical factor influencing virus inactivation by HPP. The optimal initial temperature during HPP varies greatly between different viruses (27,28,(30)(31)(32)(33)(34). In this study, we choose to compare two different initial temperatures, 4°C and 20°C, for their influence on HPP inactivation of the seven RV strains.…”

Evaluation of the Porcine Gastric Mucin Binding Assay for High-Pressure-Inactivation Studies Using Murine Norovirus and Tulane Virus

“…Interestingly, greater than 2 log unit reductions of the RNA copy numbers could be achieved for HuNoV GI.1 and GII.4. HHP mainly targets the capsids and not the genomes of the viruses (22,30,31). A previous study has shown that HHP disrupts the structure of the viral capsid of MNV-1 and not the primary or secondary structure of the VP1 protein, which plays a role in viral attachment (22).…”

Variable High-Pressure-Processing Sensitivities for Genogroup II Human Noroviruses

“…High-pressure processing (HPP) has come to the forefront as a promising intervention for viral inactivation in foods since it has been reported to effectively inactivate some foodborne viruses (such as hepatitis A virus and rotavirus), prevent internalization of particles, and inactivate both surface-contaminated and internalized particles (11,13,(15)(16)(17). In recent years, HPP has been used to treat high-risk foods for virus contamination, including fruit and vegetable product categories (e.g., salsa, apple sauce, and various fruit blends and purees) and shellfish (e.g., oysters and clams).…”