Development of Strategies to Minimize the Risk of Listeria monocytogenes Contamination in Radish, Oriental Melon, and Carrots

Contamination by Listeria monocytogenes in packaged produce is a major concern. The purpose of this study was to find natural and affordable sanitizers to reduce L. monocytogenes contamination in agricultural products. Organic acids, ultraviolet-C (UV-C), and ethanol were analyzed either alone or in combination to assess their ability to reduce L. monocytogenes population in radish, oriental melon, and carrot samples. In radish samples, 3% malic acid combined with UV-C at a dosage of 144 mj/cm2 significantly reduced (>4 log CFU/g) the population of L. monocytogenes (1.44 ± 0.5) compared to the control sample (5.14 ± 0.09). In the case of the melon samples, exposure to UV-C at a dosage of 144 mj/cm2 combined with 3% lactic acid (2.73 ± 0.75) or 50% ethanol (2.30 ± 0.01) was effective against L. monocytogenes compared to the control sample (5.10 ± 0.19). In carrot samples, 3% lactic acid combined with 144 mj/cm2 dosage UV-C reduced L. monocytogenes population (4.48 ± 0.25) more than in the control sample (5.85 ± 0.08). These results reveal that sanitizers that are effective for one crop are less effective for another crop indicating that effective prevention methods should be customized for each crop to prevent pathogen cross contamination during postharvest washing.

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Effect of Ultraviolet-A (UV-A) and Ultraviolet-C (UV-C) Light on Mechanical Properties of Oyster Mushrooms during Growth

Journal of Biophysics ◽

10.1155/2014/687028 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 3

Author(s):

Tindibale L. Edward ◽

M. S. K. Kirui ◽

Josiah O. Omolo ◽

Richard G. Ngumbu ◽

Peter M. Odhiambo

Keyword(s):

Mechanical Properties ◽

Storage Modulus ◽

Loss Factor ◽

Loss Modulus ◽

Control Sample ◽

Ultraviolet A ◽

Significant Difference ◽

Ultraviolet C ◽

Oyster Mushrooms ◽

Uv C

This study investigated the effects of ultraviolet-A (UV-A) and ultraviolet-C (UV-C) light on the mechanical properties in oyster mushrooms during the growth. Experiments were carried out with irradiation of the mushrooms with UV-A (365 nm) and UV-C (254 nm) light during growth. The exposure time ranged from 10 minutes to 60 minutes at intervals of 10 minutes and irradiation was done for three days. The samples for experimental studies were cut into cylindrical shapes of diameter 12.50 mm and thickness 3.00 mm. The storage modulus, loss modulus, and loss factor of the irradiated samples and control samples were determined for both UV bands and there was a significant difference between the storage modulus, loss modulus, and loss factor of the irradiated samples by both UV bands with reference to the control sample, P<0.05. UV-C light irradiated samples had higher loss modulus and loss factor but low storage modulus as temperature increased from 35 to 100°C with respect to the control sample while UV-A light irradiated samples had lower loss modulus, low loss factor, and higher storage modulus than UV-C irradiated samples.

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Effect of UV-C Irradiation and Lactic Acid Application on the Inactivation of Listeria monocytogenes and Lactic Acid Bacteria in Vacuum-Packaged Beef

Foods ◽

10.3390/foods10061217 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1217

Author(s):

Giannina Brugnini ◽

Soledad Rodríguez ◽

Jesica Rodríguez ◽

Caterina Rufo

Keyword(s):

Lactic Acid ◽

Listeria Monocytogenes ◽

Lactic Acid Bacteria ◽

Quadratic Model ◽

Meat Color ◽

Minimal Impact ◽

Log Reduction ◽

Combined Application ◽

Meat Samples ◽

Uv C

The objective of this study was to test the effect of the combined application of lactic acid (0–5%) (LA) and UV-C light (0–330 mJ/cm2) to reduce Listeria monocytogenes and lactic acid bacteria (LAB) on beef without major meat color (L *, a *, b *) change and its impact over time. A two-factor central composite design with five central points and response surface methodology (RSM) were used to optimize LA concentration and UV-C dose using 21 meat pieces (10 g) inoculated with L. monocytogenes (LM100A1). The optimal conditions were analyzed over 8 weeks. A quadratic model was obtained that predicted the L. monocytogenes log reduction in vacuum-packed beef treated with LA and UV-C. The maximum log reduction for L. monocytogenes (1.55 ± 0.41 log CFU/g) and LAB (1.55 ± 1.15 log CFU/g) with minimal impact on meat color was achieved with 2.6% LA and 330 mJ/cm2 UV-C. These conditions impaired L. monocytogenes growth and delayed LAB growth by 2 weeks in vacuum-packed meat samples throughout 8 weeks at 4 °C. This strategy might contribute to improving the safety and shelf life of vacuum-packed beef with a low impact on meat color.

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Effectiveness of Ultraviolet-C Room Disinfection on Preventing Healthcare-Associated Clostridioides difficile Infection

Infection Control and Hospital Epidemiology ◽

10.1017/ice.2020.512 ◽

2020 ◽

Vol 41 (S1) ◽

pp. s33-s33

Author(s):

Michihiko Goto ◽

Erin Balkenende ◽

Gosia Clore ◽

Rajeshwari Nair ◽

Loretta Simbartl ◽

...

Keyword(s):

Acute Care ◽

Acute Care Hospitals ◽

Incidence Rates ◽

Positive Test ◽

Negative Binomial Regression Model ◽

Test Results ◽

Clostridioides Difficile ◽

Ultraviolet C ◽

Healthcare Associated ◽

Uv C

Background: Enhanced terminal room cleaning with ultraviolet C (UVC) disinfection has become more commonly used as a strategy to reduce the transmission of important nosocomial pathogens, including Clostridioides difficile, but the real-world effectiveness remains unclear. Objectives: We aimed to assess the association of UVC disinfection during terminal cleaning with the incidence of healthcare-associated C. difficile infection and positive test results for C. difficile within the nationwide Veterans Health Administration (VHA) System. Methods: Using a nationwide survey of VHA system acute-care hospitals, information on UV-C system utilization and date of implementation was obtained. Hospital-level incidence rates of clinically confirmed hospital-onset C. difficile infection (HO-CDI) and positive test results with recent healthcare exposures (both hospital-onset [HO-LabID] and community-onset healthcare-associated [CO-HA-LabID]) at acute-care units between January 2010 and December 2018 were obtained through routine surveillance with bed days of care (BDOC) as the denominator. We analyzed the association of UVC disinfection with incidence rates of HO-CDI, HO-Lab-ID, and CO-HA-LabID using a nonrandomized, stepped-wedge design, using negative binomial regression model with hospital-specific random intercept, the presence or absence of UVC disinfection use for each month, with baseline trend and seasonality as explanatory variables. Results: Among 143 VHA acute-care hospitals, 129 hospitals (90.2%) responded to the survey and were included in the analysis. UVC use was reported from 42 hospitals with various implementation start dates (range, June 2010 through June 2017). We identified 23,021 positive C. difficile test results (HO-Lab ID: 5,014) with 16,213 HO-CDI and 24,083,252 BDOC from the 129 hospitals during the study period. There were declining baseline trends nationwide (mean, −0.6% per month) for HO-CDI. The use of UV-C had no statistically significant association with incidence rates of HO-CDI (incidence rate ratio [IRR], 1.032; 95% CI, 0.963–1.106; P = .65) or incidence rates of healthcare-associated positive C. difficile test results (HO-Lab). Conclusions: In this large quasi-experimental analysis within the VHA System, the enhanced terminal room cleaning with UVC disinfection was not associated with the change in incidence rates of clinically confirmed hospital-onset CDI or positive test results with recent healthcare exposure. Further research is needed to understand reasons for lack of effectiveness, such as understanding barriers to utilization.Funding: NoneDisclosures: None

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Listeria monocytogenes survival in the presence of malic acid, lactic acid or blueberry extract

Journal of Berry Research ◽

10.3233/jbr-160143 ◽

2017 ◽

Vol 7 (1) ◽

pp. 33-41

Author(s):

Anibal Concha-Meyer ◽

Joseph D. Eifert ◽

Robert C. Williams ◽

Joseph E. Marcy ◽

Gregory E. Welbaum

Keyword(s):

Lactic Acid ◽

Listeria Monocytogenes ◽

Malic Acid

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Ultraviolet-C as a Viable Reprocessing Method for Disposable Masks and Filtering Facepiece Respirators

Polymers ◽

10.3390/polym13050801 ◽

2021 ◽

Vol 13 (5) ◽

pp. 801

Author(s):

Talita Nicolau ◽

Núbio Gomes Filho ◽

Andrea Zille

Keyword(s):

Literature Review ◽

Systematic Literature Review ◽

Personal Protective Equipment ◽

State Of The Art ◽

Protective Equipment ◽

Multiple Methods ◽

Ultraviolet C ◽

Single Use ◽

Uv C ◽

New Strategies

In normal conditions, discarding single-use personal protective equipment after use is the rule for its users due to the possibility of being infected, particularly for masks and filtering facepiece respirators. When the demand for these protective tools is not satisfied by the companies supplying them, a scenario of shortages occurs, and new strategies must arise. One possible approach regards the disinfection of these pieces of equipment, but there are multiple methods. Analyzing these methods, Ultraviolet-C (UV-C) becomes an exciting option, given its germicidal capability. This paper aims to describe the state-of-the-art for UV-C sterilization in masks and filtering facepiece respirators. To achieve this goal, we adopted a systematic literature review in multiple databases added to a snowball method to make our sample as robust as possible and encompass a more significant number of studies. We found that UV-C’s germicidal capability is just as good as other sterilization methods. Combining this characteristic with other advantages makes UV-C sterilization desirable compared to other methods, despite its possible disadvantages.

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Inactivation of Candida auris and Candida albicans by Ultraviolet-C

Infection Control and Hospital Epidemiology ◽

10.1017/ice.2020.868 ◽

2020 ◽

Vol 41 (S1) ◽

pp. s292-s292

Author(s):

William Rutala ◽

Hajime Kanamori ◽

Maria Gergen ◽

Emily Sickbert-Bennett ◽

David Jay Weber

Keyword(s):

Infection Prevention ◽

Antifungal Drugs ◽

Candida Auris ◽

Healthcare Facilities ◽

Environmental Surfaces ◽

Route Of Transmission ◽

Indirect Exposure ◽

Ultraviolet C ◽

Severe Infections ◽

Uv C

Background:Candida auris is an emerging fungal pathogen that is often resistant to major classes of antifungal drugs. It is considered a serious global health threat because it has caused severe infections with frequent mortality in over a dozen countries. C. auris can survive on healthcare environmental surfaces for at least 7 days, and it causes outbreaks in healthcare facilities. C. auris has an environmental route of transmission. Thus, infection prevention strategies, such as surface disinfection and room decontamination technologies (eg, ultraviolet [UV-C] light), will be essential to controlling transmission. Unfortunately, data are limited regarding the activity of UV-C to inactivate this pathogen. In this study, a UV-C device was evaluated for its antimicrobial activity against C. auris and C. albicans. Methods: We tested the antifungal activity of a single UV-C device using the vegetative bacteria cycle, which delivers a reflected dose of 12,000 µW/cm2. This testing was performed using Formica sheets (7.6 × 7.6 cm; 3 × 3 inches). The carriers were inoculated with C. auris or C. albicans and placed horizontal on the surface or vertical (ie, perpendicular) to the vertical UV-C lamp and at a distance from 1. 2 m (~4 ft) to 2.4 m (~8 ft). Results: Direct UV-C, with or without FCS (log10 reduction 4.57 and 4.45, respectively), exhibited a higher log10 reduction than indirect UV-C for C. auris (log10 reduction 2.41 and 1.96, respectively), which was statistically significant (Fig. 1 and Table 1). For C. albicans, although direct UV-C had a higher log10 reduction (log10 reduction with and without FCS, 5.26 and 5.07, respectively) compared to indirect exposure (log10 reduction with and without FCS, 3.96 and 3.56, respectively), this difference was not statistically significant. The vertical UV had statistically higher log10 reductions than horizontal UV against C. auris and C. albicans with FCS and without FCS. For example, for C. auris with FCS the log10 reduction for vertical surfaces was 4.92 (95% CI 3.79, 6.04) and for horizontal surfaces the log10 reduction was 2.87 (95% CI, 2.36–3.38). Conclusions:C. auris can be inactivated on environmental surfaces by UV-C as long as factors that affect inactivation are optimized (eg, exposure time). These data and other published UV-C data should be used in developing cycle parameters that prevent contaminated surfaces from being a source of acquisition by staff or patients of this globally emerging pathogen.Funding: NoneDisclosures: None

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Effect of lactic acid bacteria on Listeria monocytogenes infection and innate immunity in rabbits

Czech Journal of Animal Science ◽

10.17221/247/2019-cjas ◽

2020 ◽

Vol 65 (No. 1) ◽

pp. 23-30 ◽

Cited By ~ 2

Author(s):

Heping Zhao ◽

Feike Zhang ◽

Jun Chai ◽

Jianping Wang

Keyword(s):

Lactic Acid ◽

Listeria Monocytogenes ◽

Lactic Acid Bacteria ◽

Positive Control ◽

Negative Control ◽

Listeriolysin O ◽

Serum Iga ◽

Probiotic Lactic Acid Bacteria ◽

Spleen And Lymph Nodes ◽

Proinflammatory Factors

The present study aimed to investigate the effect of probiotic lactic acid bacteria (LAB) addition on Listeria monocytogenes translocation and its toxin listeriolysin O (LLO), proinflammatory factors, immune organ indexes and serum immunoglobulins in farmed rabbits. Five treatments included negative control (NC), positive control (PC) with L. monocytogenes infection and supplemental LAB at 3.0 × 106 (low-LAB, L-LAB), 3.0 × 108 (medium-LAB, M-LAB) and 3.0 × 1010 (high-LAB, H-LAB) CFU/kg of diet, respectively. The LAB was a mixture of equal amounts of Lactobacillus acidophilus (ACCC11073), Lactobacillus plantarum (CICC21863) and Enterococcus faecium (CICC20430). A total of 180 weaned rabbits (negative for L. monocytogenes) were randomly assigned to 5 groups with 6 replicates of 6 rabbits each in response to the 5 treatments. L. monocytogenes infection occurred on the first day of feeding trial and dietary LAB supplementation lasted for 14 days. The results showed that on days 7 and 14 post administration, L. monocytogenes in caecum, liver, spleen and lymph nodes was reduced in M-LAB and H-LAB compared to PC (P < 0.05), and linear and quadratic reducing trends were found in liver on day 7 (P ≤ 0.002). On day 14, mucosa LLO mRNA expression and serum TNFα, IL1β and IFNγ were reduced in the three LAB treatments (P < 0.05), and linear and quadratic trends were found on TNFα and IL1β (P ≤ 0.025); indexes of thymus and spleen, serum IgA and IgG were increased in the LAB treatments (P < 0.05). It is concluded that LAB can be used to alleviate L. monocytogenes infection and to improve the immune function of farmed animals.

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