• Journal of Environmental Health Sciences
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• v.27 no.1
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• pp.75-82
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• 2001

Microorganisms can attach firmly to food contact surface material and the resitance of adherent bacteria differ markedly from planktonic cells. Therefore, adherent cells are a potential contamination problem to the food preparation because of their high resistance. to sanitation and heat treatment. This study was carried out in order to investigate growth and decontamination of Listeria monocytogenes attached to stainless steel, glass and plastic. Listeria monocytogenes cells could attach to all types of surface at three temperatures after contact times for 24 hrs. The numbers of adherent cells were greater at higher temperatures, but not increased with incubation time. When recovery of adherent cells was investigated, after 24 grs, the numbers of adherent cells were about 10$^{7}$ , 10$^{10}$ , 11$^{11}$ at 4$^{\circ}C$, $25^{\circ}C$, 3$0^{\circ}C$ repectively. Planctonic cells decreased by 2 log cycles after exposure to the domestic sanitizer. Adherent cells showed high resistance to domestic sanitizers and that was dependent upon surface materials studied, being greatest on plastic followed by stainless steel and glass. Adherent cells were more resistant to heat treatment than planktonic cells. When adherent cells were exposed to the temperature of 5$0^{\circ}C$, 55$^{\circ}C$, 57.5$^{\circ}C$ for 10 min, their populations did not decrease significantly. When the temprature increased to 6$0^{\circ}C$, cells attached to all types of surfaces were completely inactivated for 10 min.

• Korean Journal of Food Science and Technology
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• v.52 no.1
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• pp.109-112
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• 2020

To evaluate the safety of bacteriophages for application of sanitizer, endotoxin content and cell cytotoxicity of two Escherichia coli and four Staphylococcus aureus phages were determined. Endotoxin ratio was determined by the Limulus amebocyte lysate (LAL) assay as a test for representative biological endotoxin content. The average endotoxin average content of the 9 log PFU/mL lysate was 18.6 EU/mL and that of the 10 log PFU/mL lysate was 5.9 EU/mL, suggesting that the phage lysate was not suitable for clinical applications, but suitable for food pathogen control applications. To confirm the cell cytotoxicity of the phage lysates, MTT assay was performed using Raw 264.7 cells treated with 9 log PFU/mL phages. Results of the assay indicated that the phage lysates did not significantly decrease the cell viability (p>0.05). These results indicated that bacteriophages would be suitable as a food safety sanitizer.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.11
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• pp.1696-1700
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• 2016

In this study, acorn pomace extract (APE) was developed as a natural chemical sanitizer and substitute for chlorine-based sanitizers such as sodium hypochlorite containing harmful substances. Antimicrobial activities of APE and its combined treatments with fumaric acid (FA) and mild heat against Listeria monocytogenes inoculated on red chard were examined. Among the treatments, combined treatment of 0.5% APE at $50^{\circ}C$ and 0.5% FA was the most effective, causing reduction of L. monocytogenes populations by 3.36 log CFU/g compared to the control. After combined treatment, populations of aerobic mesophilic bacteria in the red chard decreased by 2.89 log CFU/g during storage at $4^{\circ}C$ for 8 days compared to the control. Regarding color changes in red chard upon combined treatment, there was no significant change among the red chard samples. These results indicate that combined treatment of APE, FA, and mild heat can improve microbial safety of red chard without affecting quality such as color during storage.

• Journal of Microbiology and Biotechnology
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• v.33 no.6
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• pp.771-779
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• 2023

Biofilms are a significant concern in the food industry. The utilization of plant-derived compounds to inactivate biofilms on food contact surfaces has not been widely reported. Also, the increasing negative perception of consumers against synthetic sanitizers has encouraged the hunt for natural compounds as alternatives. Therefore, in this study we evaluated the antimicrobial activities of ethanol extracts, acetone extracts, and essential oils (EOs) of seven culinary herbs against Salmonella enterica serotype Typhimurium and Listeria innocua using the broth microdilution assay. Among all tested extracts and EOs, the ethanol extract of Piper betle L. exhibited the most efficient antimicrobial activities. To evaluate the biofilm inactivation effect, S. Typhimurium and L. innocua biofilms on pitted and smooth stainless steel (SS) coupons were exposed to P. betle ethanol extract (12.5 mg/ml), sodium hypochlorite (NaClO; 200 ppm), hydrogen peroxide (HP; 1100 ppm), and benzalkonium chloride (BKC; 400 ppm) for 15 min. Results showed that, for the untreated controls, higher sessile cell counts were observed on pitted SS versus smooth SS coupons. Overall, biofilm inactivation efficacies of the tested sanitizers followed the trend of P. betle extract ≥ BKC > NaClO > HP. The surface condition of SS did not affect the biofilm inactivation effect of each tested sanitizer. The contact angle results revealed P. betle ethanol extract could increase the surface wettability of SS coupons. This research suggests P. betle extract might be utilized as an alternative sanitizer in food processing facilities.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.162-167
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• 2004

In this study, untreated (UT), water soaking (WT), and sanitizing solutions [chlorine at 100 ppm (CL): ethanol at 10% (ET); hydrogen peroxide at 1% (HP); chlorine at 100 ppm + ethanol at 10%(CE); chlorine at 100 ppm + hydrogen peroxide at 1% (CH); ethanol at 10% + hydrogen peroxide at 1% (EH); chlorine at 100 ppm + ethanol at 10% + hydrogen peroxide at 1% (CEH)] were compared in terms of their antimicrobial effectiveness against natural microflora of wild cabbage (Brassica oleracea var. capitata). All samples were kept in sanitizing solutions for 2 min, and effectiveness of sanitizing agents was evaluated based on number of decimal reduction of total aerobic mesophilic, total coliforms, E. coli, lactic acid bacteria, and yeast and mold counts. Average initial levels of these organisms in samples were $9.21{\pm}0.15,\;6.60{\pm}0.06,\;6.08{\pm}0.03,\;and\;3.66{\pm}0.08\;log_{10}\;CFU/g$ for total aerobic mesophilic bacteria, total coliforms, lactic acid bacteria, and yeasts and molds, respectively, Escherichia coli was not detected in any tested samples. Decimal reduction of populations of total aerobic mesophilic, total coliforms, E. coli, lactic acid bacteria, and yeasts and molds were: in $WT\;8.09,\;5.36,\;5.82,\;and\;3.57 log_{10}\;CFU/g;\;in \;CL\;7.39,\;4.10\;5.24,\;2.45\;log_{10}\;CFU/g;\;in\;ET\;6.78,\;4.23,\;5.20,\;2.50\;log_{10}\;CFU/g;\;in\;HP\;6.11,\;4.27,\;5.28,\;2.46\;log_{10}\;CFU/g;\;in\;CE\;6.18,\;4.26,\;5.31,\;2.49\;log_{10}\;CFU/g;\;in\;CH\;6.10,\;3.77,\;5.33,\;2.46\;log_{10}\;CFU/g;\;in\;EH\;6.07\;3.82,\;4.76,\;2.41\;log_{10}\;CFU/g;\;and\;in\;CEH\;5.27,\;3.45,\;4.45,\;2.15\;log_{10}\;CFU/g,$ respectively. Statistical analysis of the results showed effectiveness of CEH sanitizing solution for elimination of microbial contamination was the highest among all sanitizer treatments.

• Journal of Food Hygiene and Safety
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• v.22 no.2
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• pp.127-131
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• 2007

This study evaluated the bactericidal effect of 10 sanitizers and disinfectants such as ethanol (75 and 95%), iodine (15 and 25 ppm), chlorine (100 and 200 ppm), quaternary ammonium, acid, hydrogen peroxide, and peroxide acetic acid against V. parahaemolyticus. Ten strains of V. parahaemolyticus isolated from Korean foods and 4 strains of standard V. parahaemolyticus were compared for efficacies of various sanitizers and disinfectants by EN 1276 method based on quantitative suspension test. Ethanol (75 and 95%), 25 ppm of iodine, 100 ppm of quaternary ammonium, 145 ppm of hydrogen peroxide and acid showed more than $5log_{10}CFU/mL$ reduction in both clean and dirty conditions. Tests result of chlorine (100 ppm) showed more than $5log_{10}CFU/mL$ reduction in clean condition. Iodine (15 ppm) showed more than $5log_{10}CFU/mL$ reduction except 4 isolated and 1 standard V. parahaemolyticus in clean condition. iodine (15 ppm) also showed under $5log_{10}CFU/mL$ reduction $(0.93{\sim}3.73log_{10}CFU/mL)$ in dirty condition. Eleven hundred ppm of hydrogen peroxide was evaluated as weak sanitizer and disinfectant due to their $0.99{\sim}4.79log_{10}CFU/mL$ reduction on both clean and dirty conditions. Consequently, ethanol, iodine (25 ppm), chlorine (200 ppm), quaternary ammonium, acid and peroxide acetic acid were thought to be effective sanitizer and disinfectant against V. parahaemolyticus.

• Journal of Food Hygiene and Safety
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• v.21 no.2
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• pp.60-64
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• 2006

In this study, we evaluated bacteriocidal effect of CaO (scallop shell powder) for the reduction of microorganism in lettuce, and compared with main chemical sanitizers such as chlorine, ethanol, hydrogen peroxide. As a result, the effectiveness of CaO showed dramatic reduction rate for total aerobic bacteria, Escherichia coli, Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, and Salmonella Typhimurium and were $5.9{\times}10^3,\;1.3{\times}10^5,\;5.9{\times}10^3,\;2.7{\times}10^6,\;3.6{\times}10^3,\;4.5{\times}10^3\;and\;2.6{\times}10^4$, respectively. CaO did not show better disinfecting efficiency than chlorine or hydrogen peroxide which were used as sanitizer. In Bacillus cereus case, it showed $10^6$ reduction rate, and were $10^2{\sim}10^5$ times better reduction than ethanol sanitizer. According to these results, CaO can alternate the currently used chemical sanitizers due to its natural origin as well as the effectiveness for sterilization.

• Microbiology and Biotechnology Letters
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• v.33 no.4
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• pp.302-307
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• 2005

The inactivation efficiency of Campylobacter jejuni were assessed in vitro and in vivo using confocal laser microscopy and flow cytometry. C. jejuni cells were inactivated with $1\%$ (w/v) trisodium phosphate (TSP) and the live cells and inactivated cells were distinguished by staining with LIVE/DEAD BacLight Bacteria Viability fluorescent probe. After treatment of TSP for 5 min, most of C. jejuni cells turned to coccoid form from original spiral shape. C. jejuni cells lost total cell viability in the absence of organic nutrients but did not lost total cell viability in the presence of organic nutrients. In vivo test, C. jejuni cells turned to viable but non-culturable (VBNC) form after TSP treatment and remained alive on chicken skin. C. jejuni cells attached on chicken meat would transform to coccoid form by sanitizer treatment, but could possibly be alive by the benefits of organic nutrients present in chicken meat.

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.423-431
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• 1975

The purpose of this investigation was to study whether limewater can be used as dairy detergent-sanitizer for dairy farm euipment compared with idophore in the milking machine. 1. Milkstone deposition was increased slightly by idophore and limewater pre-rinse but seriously increased by milking without pre-rinse for 6 days milking. 2. Milkstone deposition was increased by increasing temperature of pre-rinse sanitizer solutions. 3. Limewater rinse was more effective than idophore rinse and tap water rinse in removing butterfat. 4. Idophore and limewater rinse was more effective than tap water rinse in removing milk solid. 5. Both of idophore and limewater were found to be significantly effective for milk bactericidal. 6. It was conclused that good hygienic raw milk can be producesed from dairy farm by idophore and limewater per-rinse.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1337-1342
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• 2008

This study was conducted to investigate effects of chemical sanitizers on inhibiting foodborne pathogens, such as Listeria monocytogenes (L. monocytogenes), Salmonella Typhimurium (S. Typhimurium), and E scherichia coli O157:H7 (E. coli O157:H7), on cabbages. Cabbages were inoculated with the culture cocktail of pathogens and treated with water, 100 ppm commercial chlorine, and 50, 100, and 200 ppm chlorine dioxide ($ClO_2$) for 1, 5, and 10 min at room temperature ($22{\pm}2^{\circ}C$). Treatments with water did not significantly reduce levels of three pathogens whereas other treatments with chemical sanitizers significantly reduced levels of three pathogens. Treatment with 200 ppm $ClO_2$ for 10 min was the most effective at inhibiting pathogens and reduction levels were 1.90, 1.92, and 1.98 log CFU/g for L. monocytogens, S. Typhimurium, and E. coli O157:H7, respectively. Levels of reduction were increased with the increase of $ClO_2$ concentrations. When chemically injured cells were investigated, there were no significant differences on the levels of injured cells between before and after treatment with commercial chlorine and $ClO_2$. These results suggest that $ClO_2$ can be used as an alternative sanitizer for reducing pathogens on fresh produces.