Antibacterial efficacy of ethyl pyruvate treatment against Escherichia coli O157:H7 and Salmonella Typhimurium on cherry tomatoes

2021 ◽  
Author(s):  
G. Ucak Ozkaya ◽  
A. Besir ◽  
E. Metin ◽  
M.Z. Durak
Keyword(s):  
Escherichia Coli ◽  
Ethyl Pyruvate ◽  
Colour Properties ◽  
Escherichia Coli O157 ◽  
Antibacterial Efficacy ◽  
Organoleptic Properties ◽  
E Coli ◽  
Two Temperatures ◽  
Pathogen Populations ◽  
Cherry Tomatoes

ABSTRACTCherry tomatoes inoculated with Escherichia coli O157:H7 and Salmonella Typhimurium were treated with vaporised ethyl pyruvate (EP). The changes of microbial and organoleptic properties of the samples during storage were investigated at two temperatures (4 and 10 °C) and four EP concentrations (0, 42, 105, and 420 ppm) for 7 days at 4 °C and for 5 days 10 °C. After 3 days, 4.3 log and 3.6 log reductions in E. coli O157:H7 numbers were detected in cherry tomatoes treated with 42 ppm EP at 4 °C and at 10 °C, respectively. The highest EP treatment (420 ppm) led to 5.7 log CFU g−1 E. coli O157:H7 reduction after 1 day at 4 and 10 °C. The reduction of Salmonella Typhimurium on samples treated with 420 ppm EP was 7.7 log CFU g–1 after 1 day at 4 °C, and 6.9 log after 1 day at 10 °C. The treatment of EP can be effective at decreasing pathogen populations and can protect the organoleptic and colour properties of fresh produce.

Antibacterial Effect of Monocaprylin on Escherichia coli O157:H7 in Apple Juice

2005 ◽  
Vol 68 (9) ◽  
pp. 1895-1899 ◽  
Author(s):  
MANOJ KUMAR MOHAN NAIR ◽  
HANEM ABOUELEZZ ◽  
THOMAS HOAGLAND ◽  
KUMAR VENKITANARAYANAN
Keyword(s):  
Escherichia Coli ◽  
Apple Juice ◽  
Antibacterial Effect ◽  
Storage Temperature ◽  
Escherichia Coli O157 ◽  
Organoleptic Properties ◽  
E Coli ◽  
Low Concentrations ◽  
Storage Temperatures ◽  
Control Samples

The antibacterial effect of low concentrations of monocaprylin on Escherichia coli O157:H7 in apple juice was investigated. Apple juice alone (control) or containing 2.5 mM (0.055%) or 5 mM monocaprylin was inoculated with a five-strain mixture of E. coli O157:H7 at ~6.0 log CFU/ml. The juice samples were stored at 23 or 4°C for 14 or 21 days, respectively, and the population of E. coli O157:H7 was determined on tryptic soy agar plates supplemented with 0.6% yeast extract. At both storage temperatures, the population of E. coli O157:H7 in monocaprylin-supplemented juice samples was significantly lower (P < 0.05) than that in the control samples. The concentration of monocaprylin and the storage temperature had a significant effect on the inactivation of E. coli O157:H7 in apple juice. Monocaprylin at 5 mM was significantly more effective than 2.5 mM monocaprylin for killing E. coli O157:H7 in apple juice. Inactivation of E. coli O157:H7 by monocaprylin was more pronounced in juice stored at 23°C than in the refrigerated samples. Results of this study indicated that monocaprylin is effective for killing E. coli O157:H7 in apple juice, but detailed sensory studies are needed to determine the organoleptic properties of apple juice containing monocaprylin.

Chemical and Irradiation Treatments for Killing Escherichia coli O157:H7 on Alfalfa, Radish, and Mung Bean Seeds

2003 ◽  
Vol 66 (5) ◽  
pp. 767-774 ◽  
Author(s):  
M. L. BARI ◽  
E. NAZUKA ◽  
Y. SABINA ◽  
S. TODORIKI ◽  
K. ISSHIKI
Keyword(s):  
Escherichia Coli ◽  
Heat Treatment ◽  
Mung Bean ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Chemical Treatments ◽  
Dry Heat ◽  
Pathogen Populations ◽  
Dry Heat Treatment ◽  
Alfalfa Seeds

In this study, the effectiveness of dry-heat treatment in combination with chemical treatments (electrolyzed oxidizing [EO] water, califresh-S, 200 ppm of active chlorinated water) with and without sonication in eliminating Escherichia coli O157:H7 on laboratory-inoculated alfalfa, radish, and mung bean seeds was compared with that of dry-heat treatment in combination with irradiation treatment. The treatment of mung bean seeds with EO water in combination with sonication followed by a rinse with sterile distilled water resulted in reductions of approximately 4.0 log10 CFU of E. coli O157:H7 per g, whereas reductions of ca. 1.52 and 2.64 log10 CFU/g were obtained for radish and alfalfa seeds. The maximum reduction (3.70 log10 CFU/g) for mung bean seeds was achieved by treatment with califresh-S and chlorinated water (200 ppm) in combination with sonication and a rinse. The combination of dry heat, hot EO water treatment, and sonication was able to eliminate pathogen populations on mung bean seeds but was unable to eliminate the pathogen on radish and alfalfa seeds. Other chemical treatments used were effective in greatly reducing pathogen populations on radish and alfalfa seeds without compromising the quality of the sprouts, but these treatments did not result in the elimination of pathogens from radish and alfalfa seeds. Moreover, a combination of dry-heat and irradiation treatments was effective in eliminating E. coli O157:H7 on laboratory-inoculated alfalfa, radish, and mung bean seeds. An irradiation dose of 2.0 kGy in combination with dry heat eliminated E. coli O157:H7 completely from alfalfa and mung bean seeds, whereas a 2.5-kGy dose of irradiation was required to eliminate the pathogen completely from radish seeds. Dry heat in combination with irradiation doses of up to 2.0 kGy did not unacceptably decrease the germination percentage for alfalfa seeds or the length of alfalfa sprouts but did decrease the lengths of radish and mung bean sprouts.

Inactivation of Escherichia coli O157:H7 and Salmonella and Native Microbiota on Fresh Strawberries by Antimicrobial Washing and Coating

2018 ◽  
Vol 81 (8) ◽  
pp. 1227-1235 ◽  
Author(s):  
MINGMING GUO ◽  
TONY Z. JIN ◽  
JOSHUA B. GURTLER ◽  
XUETONG FAN ◽  
MADHAV P. YADAV
Keyword(s):  
Escherichia Coli ◽  
Foodborne Pathogens ◽  
Allyl Isothiocyanate ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Native Microflora ◽  
Pathogen Populations ◽  
Antimicrobial Treatments ◽  
Antimicrobial Effectiveness

ABSTRACT Antimicrobial washing (AW), antimicrobial coating (AC), and a combination of washing followed by coating (AW+AC) were evaluated for their ability to inactivate artificially inoculated foodborne pathogens and native microbiota on strawberries stored at 4°C. Strawberries were inoculated with a six-strain composite of Escherichia coli O157:H7 and Salmonella; treated by AW, AC, or AW+AC; and stored at 4°C for 3 weeks. The washing solution contained 90 ppm of peracetic acid, and the coating solution consisted of chitosan (1%, w/v), allyl isothiocyanate (1%, v/v), and corn-bio fiber gum (5%, w/v). The effectiveness of the antimicrobial treatments against E. coli O157:H7 and Salmonella pathogens and native microflora on strawberries and their impact on fruit quality (appearance, weight loss, color, and firmness) were determined. By the end of storage, pathogen populations on strawberries were 2.5 (AW+AC), 2.9 (AC), 3.8 (AW), and 4.2 log CFU for the positive (untreated) control. AW+AC treatments also inactivated the greatest population of native microflora, followed by the AC treatment alone. AW+AC treatments showed additional antimicrobial effectiveness against these two pathogens and native microflora. Both AW+AC and AC treatments preserved the color, texture, and appearance of strawberries throughout storage. The coating treatments (AW+AC and AC alone) further reduced the loss of moisture throughout storage. The AW treatment was the least effective in reducing populations of pathogens and native microflora and in maintaining the quality of strawberries throughout storage. This study demonstrates a method to improve the microbiological safety, shelf life, and quality of strawberries.

scholarly journals Fate of Escherichia coli O157:H7 in Manure-Amended Soil

2002 ◽  
Vol 68 (5) ◽  
pp. 2605-2609 ◽  
Author(s):  
Xiuping Jiang ◽  
Jennie Morgan ◽  
Michael P. Doyle
Keyword(s):  
Escherichia Coli ◽  
Soil Temperature ◽  
Soil Microorganisms ◽  
Soil Samples ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Contributory Factors ◽  
Pathogen Populations ◽  
Antagonistic Interactions ◽  
Amended Soil

ABSTRACT Escherichia coli O157:H7 cells survived for up to 77, >226, and 231 days in manure-amended autoclaved soil held at 5, 15, and 21°C, respectively. Pathogen populations declined more rapidly in manure-amended unautoclaved soil under the same conditions, likely due to antagonistic interactions with indigenous soil microorganisms. E. coli O157:H7 cells were inactivated more rapidly in both autoclaved and unautoclaved soils amended with manure at a ratio of 1 part manure to 10 parts soil at 15 and 21°C than in soil samples containing dilute amounts of manure. The manure-to-soil ratio, soil temperature, and indigenous microorganisms of the soil appear to be contributory factors to the pathogen's survival in manure-amended soil.

Fate of Escherichia coli O157:H7 in Ground Apples Used in Cider Production

1998 ◽  
Vol 61 (10) ◽  
pp. 1372-1374 ◽  
Author(s):  
TOMEKA L. FISHER ◽  
DAVID A. GOLDEN
Keyword(s):  
Escherichia Coli ◽  
Statistical Difference ◽  
The Other ◽  
Escherichia Coli O157 ◽  
Apple Cultivar ◽  
Mold Growth ◽  
E Coli ◽  
Significant Difference ◽  
Golden Delicious ◽  
Pathogen Populations

Survival of Escherichia coli O157:H7 in ground Golden Delicious, Red Delicious, Rome, and Winesap apples stored at 4, 10, and 25°C was determined. E. coli O157:H7 populations were monitored for up to 18 days (4°C), 12 days (10°C), and 5 days (25°C), when mold contamination became visible. At 25°C, Red Delicious apples supported survival of E. coli O157:H7 better (P < 0.05) than the other cultivars, followed by Golden Delicious and Rome apples, which were not statistically different (P > 0.05). Winesap apples were the least favorable (P < 0.05) for survival of E. coli O157:H7 at 25°C. E. coli O157:H7 was recovered at similar rates from Golden Delicious and Red Delicious apples, (P > 0.05), but pathogen populations increased in both cultivars (P < 0.05) during storage at 25°C. At 10°C, survival of E. coli O157:H7 was poorest (P < 0.05) in ground Red Delicious apples, while there was no significant difference in survival of E. coli O157:H7 among ground Golden Delicious, Rome, or Winesap cultivars (P > 0.05). When stored at 4°C, Golden Delicious and Rome apples were not statistically different in supporting survival of the pathogen (P > 0.05) and there was no statistical difference in the recovery of E. coli O157:H7 from ground Red Delicious, Rome, and Winesap apples (P > 0.05). In general, apple pH increased during storage and was associated with mold growth. Results of this investigation indicate that there is no trend toward a particular apple cultivar supporting survival of E. coli O157:H7. However, variation in apple pH during storage can negatively or positively influence E. coli O157:H7 survival at 25 °C.

Death of Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes in Garlic Butter as Affected by Storage Temperature

2002 ◽  
Vol 65 (12) ◽  
pp. 1976-1980 ◽  
Author(s):  
BARBARA B. ADLER ◽  
LARRY R. BEUCHAT
Keyword(s):  
Escherichia Coli ◽  
Listeria Monocytogenes ◽  
Pathogenic Bacteria ◽  
Storage Time ◽  
Storage Temperature ◽  
Rapid Decline ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Pathogen Populations ◽  
And Storage

Garlic is known to have antimicrobial activity against several spoilage and pathogenic bacteria. However, the fate of Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes in garlic butter has not been reported. This study was undertaken to determine the viability of these organisms in garlic butter as affected by the type of raw minced garlic added to the butter, storage temperature, and storage time. Unsalted butter at 40°C was combined with raw minced jumbo, elephant, or small-cloved garlic at a 4:1 butter/garlic ratio (wt/wt), inoculated with mixed-strain suspensions of Salmonella, E. coli O157:H7, or L. monocytogenes, and stored at 4.4, 21, or 37°C for up to 48 h. All pathogens retained their viability at 4.4°C, regardless of the presence of garlic. The addition of garlic to butter enhanced the rates of inactivation of all three pathogens at 21 and 37°C. The most rapid decline in pathogen populations was observed at 37°C. The inactivation of L. monocytogenes occurred more slowly than did that of Salmonella or E. coli O157:H7. The inactivation of Salmonella and L. monocytogenes was more rapid in jumbo garlic butter than in elephant or small-cloved garlic butter. It is concluded that Salmonella, E. coli O157:H7, and L. monocytogenes did not grow in unsalted butter, with or without garlic added (20%, wt/wt), when inoculated products were stored at 4.4, 21, and 37°C for up to 48 h.

Reduction of Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes with Electrolyzed Oxidizing Water on Inoculated Hass Avocados (Persea americana var. Hass)

2011 ◽  
Vol 74 (9) ◽  
pp. 1552-1557 ◽  
Author(s):  
O. RODRÍGUEZ-GARCIA ◽  
V. M. GONZÁLEZ-ROMERO ◽  
E. FERNÁNDEZ-ESCARTÍN
Keyword(s):  
Escherichia Coli ◽  
Listeria Monocytogenes ◽  
Salmonella Enterica ◽  
Tap Water ◽  
Bactericidal Effect ◽  
Persea Americana ◽  
Free Chlorine ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Pathogen Populations

This study was intended to evaluate the bactericidal effect of electrolyzed oxidizing water (EOW) and chlorinated water on populations of Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes inoculated on avocados (Persea americana var. Hass). In the first experiment, inoculated avocados were treated with a water wash applied by spraying tap water containing 1 mg/liter free chlorine for 15 s (WW); WW treatment and then spraying sodium hypochlorite in water containing 75 mg/liter free chlorine for 15 s (Cl75); WW treatment and then spraying alkaline EOW for 30 s (AkEW) and then spraying acid EOW (AcEW) for 15 s; and spraying AkEW and then AcEW. In another experiment, the inoculated avocados were treated by spraying AkEW and then AcEW for 15, 30, 60, or 90 s. All three pathogen populations were lowered between 3.6 and 3.8 log cycles after WW treatment. The application of Cl75 did not produce any further reduction in counts, whereas AkEW and then AcEW treatment resulted in significantly lower bacterial counts for L. monocytogenes and E. coli O157:H7 but not for Salmonella. Treatments with AkEW and then AcEW produced a significant decrease in L. monocytogenes, Salmonella, and E. coli O157:H7 populations, with estimated log reductions of 3.9 to 5.2, 5.1 to 5.9, and 4.2 to 4.9 log CFU/cm2, respectively. Spraying AcEW for more than 15 s did not produce any further decrease in counts of Salmonella or E. coli O157:H7, whereas L. monocytogenes counts were significantly lower after spraying AcEW for 60 s. Applying AkEW and then AcEW for 15 or 30 s seems to be an effective alternative to reduce bacterial pathogens on avocado surfaces.

Reduction of Escherichia coli O157:H7 in Fresh Spinach, Using Lactic Acid Bacteria and Chlorine as a Multihurdle Intervention

2010 ◽  
Vol 73 (2) ◽  
pp. 358-361 ◽  
Author(s):  
S. E. GRAGG ◽  
M. M. BRASHEARS
Keyword(s):  
Escherichia Coli ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Shelf Life ◽  
Escherichia Coli O157 ◽  
Life Study ◽  
E Coli ◽  
Industry Standard ◽  
Retail Display ◽  
Pathogen Populations

A 12-day shelf life study was conducted at 7°C to determine whether Escherichia coli O157:H7 on spinach can be controlled effectively by selected strains of lactic acid bacteria (LAB) alone or in combination with chlorine as a multihurdle intervention. The multihurdle intervention consisted of both LAB and chlorine and was applied to spinach as a rinse and evaluated in comparison to LAB alone and chlorine and water rinses. Reductions achieved by all treatments also were compared with those observed for an inoculated control. The spinach was inoculated by submersion in a solution containing an E. coli O157:H7 cocktail at 1.0 × 106 CFU/ml. LAB were applied postharvest at a concentration of 2.0 × 108 CFU/ml, and 200 ppm of chlorine was used for the chlorine rinse. All spinach samples were packaged in commercial packaging, held in a retail display case, and tested for E. coli O157:H7 on days 0, 1, 3, 6, 9, and 12 using the Neo-Grid filtration system and CHROMagar. Survival of LAB throughout the shelf life also was determined. Significant reductions in pathogen populations were achieved by water (P < 0.0008), LAB (P < 0.0001), chlorine (P < 0.0001), and multihurdle (P < 0.0001) treatments when compared with controls. The multihurdle treatment produced the greatest reduction from control populations, a reduction of 1.91 log CFU/ml. This reduction was significantly greater than that achieved with water (P < 0.0001), LAB (P = 0.0025), and chlorine (P < 0.0001) alone, indicating that the application of chlorine and LAB is most effective as a combination treatment. The results obtained from this study indicate that the industry standard chlorine wash may be more effective when applied in combination with LAB.

Impact of pH Enhancement on Populations of Salmonella, Listeria monocytogenes, and Escherichia coli O157:H7 in Boneless Lean Beef Trimmings†

2003 ◽  
Vol 66 (5) ◽  
pp. 874-877 ◽  
Author(s):  
STEVEN E. NIEBUHR ◽  
J. S. DICKSON
Keyword(s):  
Escherichia Coli ◽  
Listeria Monocytogenes ◽  
Ground Beef ◽  
Final Concentration ◽  
Escherichia Coli O157 ◽  
Ammonia Gas ◽  
E Coli ◽  
Lean Beef ◽  
Pathogen Populations ◽  
Multiple Strains

Boneless lean beef trimmings were inoculated with multiple strains of salmonellae, Listeria monocytogenes, and Escherichia coli O157:H7 at levels of ca. 6 log10 CFU/g. pH enhancement with ammonia gas was then used to increase the pH of the trimmings to ca. 9.6. The product was then frozen, chipped, and compressed into blocks. pH enhancement reduced the populations of salmonellae, L. monocytogenes, and E. coli O157:H7 by approximately 4, 3, and 1 log10 cycles, respectively. After the product had been frozen and compressed into blocks, no salmonellae or E. coli O157:H7 were detectable by enumeration or after enrichment and isolation. The final populations of L. monocytogenes were reduced by ca. 3 log10 cycles relative to the initial populations. When uninoculated pH-enhanced lean boneless trimmings were blended with inoculated ground beef to a final concentration of 15% (wt/wt), pathogen populations in the ground beef were reduced by approximately 0.2 log10 cycles.

Combination Treatments for Killing Escherichia coli O157:H7 on Alfalfa, Radish, Broccoli, and Mung Bean Seeds

2009 ◽  
Vol 72 (3) ◽  
pp. 631-636 ◽  
Author(s):  
M. L. BARI ◽  
D. NEI ◽  
K. ENOMOTO ◽  
S. TODORIKI ◽  
S. KAWAMOTO
Keyword(s):  
Escherichia Coli ◽  
Heat Treatment ◽  
Mung Bean ◽  
Germination Rate ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Dry Heat ◽  
Pathogen Populations ◽  
Dry Heat Treatment ◽  
Alfalfa Seeds

In this study, the effectiveness of prolonged dry-heat treatment (50°C) alone or in combination with chemical treatments (1% oxalic acid, 0.03% phytic acid, 50% ethanol, electrolyzed acidic water, and electrolyzed alkaline water) in eliminating Escherichia coli O157:H7 on laboratory-inoculated alfalfa, radish, broccoli, and mung bean seeds was compared with that of dry-heat treatment in combination with irradiation treatment. Dry-heat treatment for 17 or 24 h alone could reduce E. coli O157:H7 numbers to below detectable levels in radish, broccoli, and alfalfa seeds, but was unable to reduce the pathogen numbers to below the detectable level in mung bean seeds. In addition, dry-heat treatment for 17 h plus sanitizer treatments were effective in greatly reducing pathogen populations on radish, broccoli, and alfalfa seeds, without compromising the quality of the sprouts, but these treatments did not eliminate the pathogen from radish and alfalfa seeds. Seventeen hours of dry heat followed by a 1.0-kGy dose of irradiation completely eliminated E. coli O157:H7 from radish and mung bean seeds, whereas only a minimum radiation dose of 0.25 kGy was required to completely eliminate the pathogen from broccoli and alfalfa seeds. Dry heat in combination with radiation doses of up to 1.0 kGy did not negatively impact the seed germination rate or length of alfalfa, broccoli, and radish seeds or the length of alfalfa, broccoli, and radish sprouts, but did decrease the length of mung bean sprouts.

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