Surrogate organisms for pathogenic O157:H7 and non-O157 Escherichia coli strains for apple juice treatments by UV-C light at three monochromatic wavelengths

Orłowska, Marta; Koutchma, Tatiana; Kostrzynska, Magdalena; Tang, Joshua

doi:10.1016/j.foodcont.2014.08.004

Cited by 35 publications

(13 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The GInaFiT software was used to test linear and non-linear survival curves [40], using the biphasic [41],Weibull [42], Weibull plus tail [43] and biphasic plus shoulder [40] models. The GInaFiT software has been used to test survival kinetics of different bacteria and viruses when submitted to heat treatment or UV-C irradiation [44].…”

Section: Modeling Of Inactivationmentioning

confidence: 99%

Evaluation of the effectiveness of the SurePure Turbulator ultraviolet-C irradiation equipment on inactivation of different enveloped and non-enveloped viruses inoculated in commercially collected liquid animal plasma

et al. 2019

View full text Add to dashboard Cite

The objective of this study was to evaluate the effectiveness of the SurePure Turbulator ultraviolet-C (UV-C, 254 nm wavelength) irradiation equipment on inactivation of different enveloped and non-enveloped viruses in commercially collected liquid animal plasma. Specifically, Pseudorabies virus (PRV), Porcine reproductive and respiratory syndrome virus (PRRSV), Porcine epidemic diarrhea virus (PEDV), Bovine viral diarrhea virus (BVDV), Classical swine fever virus (CSFV), Swine influenza virus (SIV) as enveloped viruses and Porcine parvovirus (PPV), Swine vesicular disease virus (SVDV), Porcine circovirus type 2 (PCV-2) and Senecavirus A (SVA) as non-enveloped viruses, were inoculated in bovine or porcine plasma and subjected to different UV-C irradiation doses (0, 750, 1500, 3000, 6000 and 9000 J/L) using an UV-C device developed for opaque liquid working under turbulent flow. The enveloped viruses tested were inactivated at < 3000 J/L of UV-C, being the dose needed to inactivate 4 log TCID 50 (4D) of 1612 J/L for PRV,1004 J/L for PRRSV, 1953 J/L for PEDV, 1639 J/L for SIV, 1641 J/L for CSFV and 1943 J/L for BVDV. The non-enveloped viruses tended to have higher 4D values: 2161 J/L for PPV, 3223 J/L for SVA and 3708 J/L for SVDV. Because the initial viral concentration was <4.0 Log for PCV-2, it was not possible to calculate the 4D value for this virus. In conclusion, these results demonstrated that the SurePure Turbulator UV-C treatment system is capable of inactivating significant levels of swine viruses inoculated in commercially collected porcine or bovine plasma. It was concluded that irradiation with UV-C can provide an additional redundant biosafety feature in the manufacturing process of spray-dried animal plasma.

show abstract

Section: Modeling Of Inactivationmentioning

confidence: 99%

Evaluation of the effectiveness of the SurePure Turbulator ultraviolet-C irradiation equipment on inactivation of different enveloped and non-enveloped viruses inoculated in commercially collected liquid animal plasma

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Of course, for applications on solid food, the suitability of surrogate bacteria needs to be verified as the ability for attachment, biofilm formation, and other characteristics may differ between O157:H7 and nonpathogenic/attenuated E. coli strains. Orlowska, Koutchma, Kostrzynska, and Tang () found that E. coli ATCC 8739 met the criteria for a UV‐C surrogate organism for O157:H7 and non‐O157 STEC strains. Oteiza, Peltzer, Gannuzzi, and Zaritzky () found that EDL933 had a similar sensitivity to UV‐C in juices as did ATCC 25922.…”

Section: Resultsmentioning

confidence: 99%

“…Orlowska, Koutchma, Kostrzynska, and Tang (2015) found that E. coli ATCC 8739 met the criteria for a UV-C surrogate organism for O157:…”

Section: Statistical Analysesmentioning

confidence: 99%

Sensitivity of pathogenic and attenuated E. coli O157:H7 strains to ultraviolet‐C light as assessed by conventional plating methods and ethidium monoazide‐PCR

Yan

Liu

Gurtler

et al. 2017

Journal of Food Safety

View full text Add to dashboard Cite

The UV‐C sensitivity of six pathogenic Escherichia coli O157:H7 strains associated with recent outbreaks of foodborne illnesses and five attenuated/nonpathogenic E. coli O157:H7 strains was investigated using conventional plating method, and real time PCR with and without ethidium monoazide (EMA) pretreatment. Results showed that the nonpathogenic/attenuated E. coli ATCC 25922, 6980‐2, and 6982‐2 had more or similar resistance to UV‐C compared to the pathogenic strains. The UV‐C inhibition on the PCR amplification of DNA correlated well with UV‐C dose, as indicated by the cycle threshold (Ct), regardless of EMA pretreatment. The Ct values increased linearly with increasing UV‐C doses. Cell membrane was damaged only at high doses when UV‐C inactivated more than 6 log CFU of bacteria. Overall, our results suggest that E. coli strains have different sensitivities to UV‐C and that EMA‐PCR is a useful tool to assess cell damage caused by UV‐C. Practical applications Ultraviolet (UV) light, as one of the postharvest interventions, is simple to implement and inexpensive for commercial applications. To conduct trials on a large scale or at a commercial setting, nonpathogenic/attenuated surrogates of pathogenic bacteria should be used, due to the difficulty for containment and post‐treatment decontamination of equipment and the environment. We demonstrated the variations in UV‐C sensitivity among pathogenic and nonpathogenic E. coli strains. Three attenuated/nonpathogenic strains of E. coli had similar sensitivities as the pathogenic strains, and therefore, could serve as surrogates. Furthermore, cell membrane was not affected by moderate doses of UV‐C treatments, even though the bacteria were not cultivable. The information will be useful for researchers to conduct scale‐up trials, and to optimize UV‐C technology for microbial safety enhancement.

show abstract

“…In particular, excilamps are considered an attractive UV source due to characteristics such as their wavelength selectivity, fast warm-up, long lifetime, and high radiant intensity, as well as the absence of mercury (29)(30)(31). Excilamps can emit nearly monochromatic radiation, with wavelengths ranging from 172 to 345 nm, depending on the type of rare gas and halogen used (31,32). Recent studies, including ours, to evaluate the germicidal effects of various forms of excilamps (Xe 2 , KrCl, and XeBr excilamps with maximum emissions at 172, 222, and 282 nm, respectively) and conventional mercury lamps emitting 254-nm radiation revealed that the KrCl excilamp, emitting at a 222-nm wavelength, resulted in the highest log reductions of pathogens among other excilamps as well as mercury lamps emitting at a 254-nm wavelength at the same incident dose, which means that the 222-nm KrCl excilamp has a greater inactivation effect than those of other excilamps or the mercury vapor lamp (29,(32)(33)(34).…”

mentioning

confidence: 99%

“…Excilamps can emit nearly monochromatic radiation, with wavelengths ranging from 172 to 345 nm, depending on the type of rare gas and halogen used (31,32). Recent studies, including ours, to evaluate the germicidal effects of various forms of excilamps (Xe 2 , KrCl, and XeBr excilamps with maximum emissions at 172, 222, and 282 nm, respectively) and conventional mercury lamps emitting 254-nm radiation revealed that the KrCl excilamp, emitting at a 222-nm wavelength, resulted in the highest log reductions of pathogens among other excilamps as well as mercury lamps emitting at a 254-nm wavelength at the same incident dose, which means that the 222-nm KrCl excilamp has a greater inactivation effect than those of other excilamps or the mercury vapor lamp (29,(32)(33)(34). In particular, the Yin et al study (35) comparing the inactivation effect at the same energy level that is imposed entirely on cells, excluding the matrix effect of the medium, by using the actual dose imparted to apple juice, which was calculated by taking into account the absorption coefficient of the apple juice sample to be treated, reported that the 222-nm KrCl excilamp reduced E. coli O157:H7 in apple juice by almost 1 log more than the 282-nm XeBr excilamp or 254-nm mercury lamp.…”

mentioning

confidence: 99%

Increased Resistance ofSalmonella entericaSerovar Typhimurium andEscherichia coliO157:H7 to 222-Nanometer Krypton-Chlorine Excilamp Treatment by Acid Adaptation

Kang

2019

Appl Environ Microbiol

View full text Add to dashboard Cite

In this study, we examined the change in resistance ofSalmonella entericaserovar Typhimurium andEscherichia coliO157:H7 to 222-nm krypton-chlorine (KrCl) excilamp treatment as influenced by acid adaptation and identified a mechanism of resistance change. In addition, we measured changes in apple juice quality indicators, such as color, total phenols, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity, during treatment. Non-acid-adapted and acid-adapted pathogens were induced by growing the cells in tryptic soy broth without dextrose (TSB w/o D) at pH 7.3 and in TSB w/o D at pH 5.0 (adjusted with HCl), respectively. For the KrCl excilamp treatment, acid-adapted pathogens exhibited significantly (P < 0.05) higher D5dvalues, which indicate dosages required to achieve a 5-log reduction, than those for non-acid-adapted pathogens in both commercially clarified apple juice and phosphate-buffered saline (PBS), and the pathogens in the juice showed significantly (P < 0.05) higher D5dvalues than those for pathogens in PBS because of the UV-absorbing characteristics of apple juice. Through mechanism identification, it was found that the generation of lipid peroxidation in the cell membrane, inducing cell membrane destruction, was significantly (P < 0.05) lower in acid-adapted cells than in non-acid-adapted cells for the same amount of reactive oxygen species (ROS) generated at the same dose because the ratio of unsaturated to saturated fatty acids (USFA/SFA) in the cell membrane was significantly (P < 0.05) decreased as a result of acid adaptation. Treated apple juice showed no significant (P > 0.05) difference in quality indicators compared to those of untreated controls during treatment at 1,773 mJ/cm2.IMPORTANCEThere is a need for novel, mercury-free UV lamp technology to replace germicidal lamps containing harmful mercury, which are routinely utilized for UV pasteurization of apple juice. In addition, consideration of the changes in response to antimicrobial treatments that may occur when pathogens are adapted to the acid in an apple juice matrix is critical to the practical application of this technology. Based on this, an investigation using 222-nm KrCl excilamp technology, an attractive alternative to mercury lamps, was conducted. Our study demonstrated increased resistance to 222-nm KrCl excilamp treatment as pathogens adapted to acids, and this was due to changes in reactivity to ROS with changes in the fatty acid composition of the cell membrane. Despite increased resistance, the 222-nm KrCl excilamp achieved pathogen reductions of 5 log or more at laboratory scale without affecting apple juice quality. These results provide valuable baseline data for application of 222-nm KrCl excilamps in the apple juice industry.

show abstract

Surrogate organisms for pathogenic O157:H7 and non-O157 Escherichia coli strains for apple juice treatments by UV-C light at three monochromatic wavelengths

Cited by 35 publications

References 37 publications

Evaluation of the effectiveness of the SurePure Turbulator ultraviolet-C irradiation equipment on inactivation of different enveloped and non-enveloped viruses inoculated in commercially collected liquid animal plasma

Evaluation of the effectiveness of the SurePure Turbulator ultraviolet-C irradiation equipment on inactivation of different enveloped and non-enveloped viruses inoculated in commercially collected liquid animal plasma

Sensitivity of pathogenic and attenuated E. coli O157:H7 strains to ultraviolet‐C light as assessed by conventional plating methods and ethidium monoazide‐PCR

Increased Resistance ofSalmonella entericaSerovar Typhimurium andEscherichia coliO157:H7 to 222-Nanometer Krypton-Chlorine Excilamp Treatment by Acid Adaptation

Contact Info

Product

Resources

About