• The Korean Journal of Food And Nutrition
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• v.14 no.6
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• pp.548-561
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• 2001

Listeria spp. from sea water, fishes and shellfishes have been troubled in many countries. So we exam ined its distribution rates, biochemical characteristics of a separated strain, growth curve of pH at set times to 4 species of standard strain, and yes or no of growth inhibition for precautionary measure of food poisoning by L. monocytogenes, garlic, mustard, wasabi, and green tea extracts including sensitivity of antibiotics 10 species. As its results, check numbers of its positivity to Listeria spp. were 32 species in total examination body 200 species, and its isolation rates were 16%, L. innocua was 14.0%, L. monocytogenes 1.0%, and L. seeligeri 1.0% by the strain species. All the standard strain of 4 species showed growth inhibition bellow pH 3.0, its pH conditions of the optimum growth at 7.0∼8.0, and its growth was more active in alkali co]tuition than in acid condition. Its growth inhibition examination by garlic extracts had an the worst effects with O.D values of 0.078∼0.210. But the case of mustard and wasabi had weakened effect, and the case of green tea had some effect as the time went by. The results of sensitivity examination of antibiotics 10 species were as fellows. L. innocua of the 16 cases showed sensitivity of 100% in all 5 species, Ampicillin, etc, and Ciprofloxacin showed sensitivity of 43.7% and gentamicin, 93.7%. But tetracycline showed tolerance of 31.3% , cefotaxine. 75%, nalidixic acid, 100%. L. monocytogenes of the 6 cases showed sensitivity of 100% in all 6 species, ciprofloxacin, etc.

• Journal of Food Hygiene and Safety
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• v.10 no.2
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• pp.89-95
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• 1995

Highly lethal Listeria monocytogenes, causing bromatoxism through vegetables, dairy products, meat products and shellfish etc, was examined for possible contamination in market beef. USDA, FDA, Malthus and Modified Cold Enrichment methods were used for the detection of Listeria spp.. Samples of domestic and imported market beef were collected from local meat shopsat Seoul, Korea. Total two hundreds and six of Listeria spp. were isolated and identified from beef. Among 206 isolates, the number of L. welshimeri was one hundred and twenty-one(44.8%). The numbers of isolated L. innocua, L. murrayi, L. monocytogenes, L. grayi, L. seeligeri, and L. ivanovii were 49(18.1%), 14(5.2%), 12(4.4%), 6(2.2%), 2(0.7%), and 2(0.7%), respectively. Detection rates of Listeria spp. varied among four methods. The highest detection rate of Listeria spp. in market beef was found at USDA method and that of L. monocytogenes was found at Malthus method.

• 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.

• The Korean Journal of Food And Nutrition
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• v.17 no.3
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• pp.254-259
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• 2004

Rapid detection of foodbome pathogens is becoming increasingly important. The requirement for faster, more reliable tests has lead to the development of a wide range of rapid methods. Among these methods, the use of systems based on nucleic acid based detection has been increasing since they offer advantages of reduction in test time and more reliable detection or identification. Random Amplification Polymorphic DNA(RAPD) method has been used to fingerprint foodbome microorganisms; Listeria monocytogenes. In this study, 10-mer primer OPG-13(5'-CTCTCCGCCA-3') was used to generate RAPD-PCR for detection of pathogenic L. monocytogenes of Listeria spp. Among 20 primers tested, OPG-13 showed on acceptable result for the differentiation of a pathogenic Listeria from non-pathogenic microorganisms. Pathogenic Listeria, L. monocytogenes(ATCC 15313, 19111, 19112, 19113) showed two bands for 700 bp and 1,500 bp while non-pathogenic bacteria, L. ivanovii, L. grayi, L. murrayi, L. innocua, L. welshimeri, and L. seeligeri had only one band sizing from 2,000 to 2,300 bp. This RAPD method proved to be a valuable to gain important information on sources of pathogenic bacteria in food industry.

• Preventive Nutrition and Food Science
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• v.3 no.2
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• pp.157-162
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• 1998

As a part of investigation for listeriosis, we attmepted iolationof Listeria spp. from commerical frozen and refrigerated foods at the supermarket level. Seven strains of Listeria spp. were isolate from 6 samples (7.15) among 84 samples of frozen foods, and ten strains of Listeria spp. were also isolated from 8 samples (7.6%)_ among 105 samples of refrigerated foods at the supermarkets in Pusan area. From a total of 189 commerical foods, the number of isolated Listeria spp. and ratio were 6 strains(3.25) of L. grayi, one strain (0.5%) of L. welshimeri, 6 strains (3.2%) of L. innocua and 4 strains (2.15) of L monocytogenes. Listeria spp. isolates except L. monocytogenes did not show $\beta$-hemolysis on blood agar and positive reaction in CAMP test with Staphyloccccus aureus. In the antibiotic susceptibility,most isolates of Listeria spp. were susceptible to 12 antibiotics such as ampicillin , cephalotin, penicillin, amikacin, gentamicin, erythromycin, kanamycin, vancomycin, tobramycin, carbenicillin , tetracycline and trimethoprim /sulfamethoxiazole. Four strains of L. monocytogenes were susceptible to ntibiotics used in this study except nitrofurantio. The serotype of 3 strains and one strain of L. monocytogenes were classified into Listeria O serotype 1 and 4, respectively.

• Fisheries and Aquatic Sciences
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• v.5 no.1
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• pp.54-58
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• 2002

The polymerase chain reaction (PCR) amplification technique was used for comparison of Listeria monocytogenes serotypes. PCR primers for the fragment of invasion-associated protein (iap) gene were highly specific for all the serotypes of L. monocytogenes. Other Listeria spp., such as Listeria ivanovii and Listeria innocua were not produced the PCR fragments by above primer set. The nucleotide sequences of PCR products showed high homologies in comparison of all the isolated serotypes except unknown type II-2. The deduced amino acid sequences of the PCR products also showed similar to one another. The various region of the PCR products, called a Thr-Asn repeat region was presented. All of isolated L. monocytogenes serotypes possessed 16 to 20 Thr-Asn repeats.

• Korean Journal of Veterinary Research
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• v.44 no.2
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• pp.217-224
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• 2004

This study was carried out to investigate the antibiotic resistance pattern of Listeria spp. and Staphylococcus aureus. A total of 17 (14.8%) L. monocytogenes, 13 (11.3%) L. innocua, 7 (7%) L. welshimeri, and 83 (72.2%) S. aureus were isolated from commercial poultry carcasses in Seoul and Kyonggi province during the period between 2001 and 2003. Antibiotic susceptibility test of all Listeria strains isolated was performed by the disk agar diffusion method. Antibiotics used in the study were as follows; Amikacin (An), Ampicillin (Am), Cephalothin (Cf), Chloramphenicol (C), Ciprofloxacin (Cip), Erythromycin (E), Gentamicin (Gm), Imipenem (Ipm), Kanamycin (K), Minocycline (Mi), Neomycin (N), Norfloxacin (Nor), Ofloxacin (Ofx), Penicillin (P), Streptomycin (S), Tetracycline (Te), Tobramycin (Nn), Trimethoprim (Tmp), Trimethoprim/Sulfamethoxazloe (Sxt), and Vancomycin (Va). The antibiotic resistance pattern of S. aureus isolates was performed by the disk agar diffusion method. For the latter program, antibiotics used to the study were as follows; Cf, C, Cip, Clindamycin (Cc), E, Gm, Ipm, Nafcillin (Nf), Oxacillin (Ox), P, Te, Sxt, and Va. Of the 17 L. monocytogenes isolates, 94.1% were resistant to Te, 88.2% to Mi, 11.8% to Nor, 11.8% to S, 5.9% to Cip, and 5.9% to C. Of 13 L. innocua, 53.8% were resistant to Te, 23.1% to Mi, 23.1% to S, 7.7% to Cip, and 7.7% to Nor. Of 7 L. welshimeri, 57.1% were resistant to Te, and 14.3% to Am. Of 83 S. aureus, 100% were resistant to Te, 86.7% to Gm, 34.9% to P, 15.7% to Cip, 12% to Cc, 9.6% to E. The multiple antibiotic resistance patterns of L. monocytogenes isolates were observed in Te Mi Cip (5.9%), Te Mi Nor (5.9%), Te Mi (76.5%), and Te Nor (5.9%). Multiple antibiotic resistance was also found in L. innocua isolates. Resistant to Te Mi S Cip Nor was 7.7%, Te Mi S (7.7%), Te Mi (7.7%), and was 7.7% to Te S. Antibiotic resistance patterns for S. aureus isolats were demonstrated to Te Gm P Cip Cc E (6.0%), Te Gm Cip Cc E (3.6%), Te Gm P Cc (1.2%), Te Gm P (15.6%), Te Gm Cip (2.4%), Te P Cip (2.4%), Te Gm Cc (1.2%), Te Gm (56.6%), Te P (9.6%), and to Te Cip (1.2%). The results of this study suggest a high incidence of Lsteria spp. and S. aureus on poultry carcasses. The contaminated poultry carcasses may be a potential vehicle for foodborne infections due to multiple antimicrobial resistant organisms.

• Journal of Microbiology and Biotechnology
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• v.26 no.9
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• pp.1551-1556
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• 2016

Broiler meat production worldwide has been plagued by lethal food-poisoning bacteria diseases, including listeriosis. A fatality rate of 15.6% was recorded in human beings in the EU in 2015. During 2013, a total of 200 poultry farm samples, including litter, chicken breast, farm feed, and drinking water, were collected to generate baseline data for the characterization of the genus Listeria in broiler poultry farms. Listeria spp. were detected in a total of 95 (47.5%) poultry farm samples. The isolates of Listeria spp. included L. innocua (28.5%), L. ivanovii (12.5%), L. welshimeri (4.5%), and L. monocytogenes and L. seeligeri (1% each). Listeria spp. contamination rates were higher in farm feed (70%), followed by litter (52.5%), chicken breasts (42.2%), and drinking water (10%). Almost all Listeria spp. isolates were resistant to more than three classes of antibiotics (multidrug resistant). Besides this, we observed a significant resistance level to penicillin and fluoroquinolone drugs. However, lower resistance levels were recorded for broad-spectrum cephalosporins. The inlA, inlC, and inlJ virulence genes were detected in almost all of the L. monocytogenes isolates. Thus, food safety management approaches and interventions at all stages of the broiler rearing cycle were needed to control cross-contamination and the zoonotic potential of listeriosis.

• Journal of Food Hygiene and Safety
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• v.20 no.4
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• pp.232-236
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• 2005

This study was performed to find out the patterns of Listeria spp. contamination during Kimbab preparation at the specialized restaurants. Samples were collected from ingredients, containers, equipments, and environments from two Kimbab restaurants from July through September, 2004. Isolation rate of Listeria spp. was $43.2\%$ among 264 samples. Strains isolated were Listeria innocua $35.9\%$, L. murrayi $6.8\%$, and L. grayii $0.3\%$. No L. monocytogenes was detected. Contamination level of ingredients, containers, equipments, and Kimbab sampled during afternoon was all significantly higher than the samples collected during morning(P < 0.05). The most influencing factor of contamination was improper handling or no disinfection procedures during Kimbab preparation. Safety controls are recommended as follows; prevention of cross-contamination during ingredients Preparation, temperature control for ingredients and Kimbab during holding, cleaning and disinfection of chopping boards and knives during preparation processing, and frequent changes of disposable gloves. Kimbab restaurants should recognize the importance of safety control using the Good Hygienic Practices.

• Korean Journal of Veterinary Research
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• v.31 no.3
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• pp.271-277
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• 1991

To investigate the epidemiological trait of listeriosis, Listeria spp were isolated from poultry meat, products and environmental specimens in chicken slaughterhouse. Also determined were isolation rates by the different enrichment procedures, the biochemical properties of isolates. In a total of 307 samples including poultry meat, liver, feathers, feces, chiller water, scalding water overflow and slaughterhouse floor, Listeria spp were isolated predominantly from scalding water overflow (90.0%), body skin before washing (66.7%), liver (20.0%) and feathers(15.0%) However, few Listeria spp were isolated from body skin after washing and feces. The higher isolation rates were obtained in the secondary enrichment procedure (7.2%) than in the primary enrichment (3.9%); after stored the secondary enrichment cultures for 2 weeks at $4^{\circ}C$, Listeria spp were present in 9.8%. The majority of the isolated Listeria spp were identical to those of the standards strains in biochemical and cultural properties. Overall, Listeria spp were present in 13.4% of the specimens tested, and were in order of prevalence of L innocua(11.1%), L monocytogenes(3.3%), L grayi(0.7%) and L murrayi(0.3%).