Salmonella Characterization in Poultry Eggs Sold in Farms and Markets in Relation to Handling and Biosecurity Practices in Ogun State, Nigeria

Salmonella remains one of the notable food-borne bacterial pathogens. It is associated with poultry and poultry products including eggs. This study investigated Salmonella distribution in eggshell and content, their antimicrobial resistance pattern, and the possible risk factors driving contamination in Ogun State, Nigeria. A total of 500 eggs (5 eggs pooled into one sample) were collected and culturally examined for the presence of Salmonella serovars. Isolates were further characterized biochemically using Microbact 20E (Oxoid) and Antimicrobial susceptibility determined by the Kirby-Bauer disk diffusion method. A total of 14 Salmonella isolates spread across 10 serovars were recovered from the 100 pooled egg samples; 10 (10%) from the market and 4 (4%) farms, 13(13%) eggshell, and 1(1%) egg content. All tested serovars were susceptible to ampicillin, chloramphenicol, florfenicol, and kanamycin. Resistance was mostly observed in sulfamethoxazole 8 (80%), followed by ciprofloxacin 5 (50%) and tetracycline 3 (30%). Sales of eggs in the market appear to be a strong factor encouraging contamination in addition to poor biosecurity and unhygienic handling of eggs on the farm.

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Bacterial Contamination Associated with Retail Chicken Carcasses in Osogbo, Nigeria

Journal of Health and Allied Sciences NU ◽

10.1055/s-0040-1703934 ◽

2015 ◽

Vol 05 (04) ◽

pp. 045-050

Author(s):

Adesiji Yemisi Olukemi ◽

Igbinigie Mavis Osas ◽

Olaitan Janet Olubukola ◽

Ogah Ikhevha Jeremiah

Keyword(s):

Diffusion Method ◽

Isolation And Identification ◽

Disk Diffusion Method ◽

E Coli ◽

Poultry Products ◽

Bacterial Contaminants ◽

Food Borne ◽

Chicken Carcass ◽

Hygiene Measures ◽

Food Borne Illness

Abstract Background: Worldwide, food borne illness is often associated with consumption of meat and poultry products sold at retail markets. A study on the bacteriological status of chicken carcass in Osogbo, Nigeria, was carried out to determine the prevalence of Arcobacter species, Escherichia coli and Staphylococcus aureus in chicken carcasses. Methodology: A total of 100 samples of chicken carcasses were collected from two major processing points in Osogbo, Nigeria. The samples were analysed for the presence of bacterial contaminants using standard microbiological isolation and identification procedures, with antimicrobial susceptibility test performed using the disk diffusion method. Result: Of hundred chicken carcasses sampled, 38% were positive for Arcobacter species and E. coli while 60% accounted for S. aureus isolates. Ninety percent of Arcobacter spp isolates were susceptible to ciprofloxacin, 85% to gentamicin, and pefloxacin, 70% to chloramphenicol and 90% were resistant to amoxicillin, 85% to augumentin and 80% to streptomycin. Hundred percent of E. coli isolates were susceptible to ciprofloxacin, pefloxacin, 95% to gentamicin and 100% were resistant to streptomycin, 85 % resistant to amoxicillin, augumentin, while 100% of S. aureus isolates were susceptible to trimethoprim sulphamethoxazole, 90% susceptible to gentamicin, 80% to streptomycin and 100% of the S.aureus isolates were resistant to ampliclox. Conclusion: The bacteriological status of chicken carcass revealed high contamination with Arcobacter, E coli and S. aureus with varying degree of antibiotic resistance therefore, improvement in meat processing procedures and strict hygiene measures towards reduction of these pathogens in food products should be encouraged.

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Evaluation of Bacterial Load and Antibiotic Resistance Pattern of Staphylococcus aureus from Ready-to-Eat Raw Beef in Bahir Dar City, Ethiopia

International Journal of Microbiology ◽

10.1155/2021/5560596 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Bizuneh Tsehayneh ◽

Taddesse Yayeh ◽

Birhan Agmas

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Bacterial Load ◽

Diffusion Method ◽

Resistance Pattern ◽

Bahir Dar ◽

Disk Diffusion Method ◽

Food Borne ◽

Antibiotic Susceptibility Test ◽

Butcher Shops

Background. Staphylococcus aureus is one of the most important causes of food-borne intoxication and the most frequent antibiotic-resistant pathogen in the world. Regular evaluation of the current safety status of food is a proactive measure to minimize the possible danger of food-borne pathogens. Therefore, this study was conducted to assess the bacterial load and antibiotic resistance profile of S. aureus from ready-to-eat raw beef in Bahir Dar city, Ethiopia. Methodology. This cross-sectional study was conducted from October 2018 to April 2019 by collecting a total of 101 raw beef samples from butcher shops using a simple random sampling method. Isolation and microbial load determination of S. aureus use were performed by conventional culture method and an antibiotic susceptibility test was conducted by using Kirby Bauer disk diffusion method on the Mueller–Hinton agar. The data were analyzed by using STATA software version 12.0. Result. Out of 101 raw beef samples, 55 (54.45%) were positive for S. aureus with a mean bacterial count of 3.40 ± 0.63 (log10 cfu/g). About 13% of butcher shops had unacceptable and potentially dangerous (above 104 cfu/g) bacterial load. High S. aureus drug resistance was observed on penicillin (92.73%) followed by cefoxitin (74.5%), tetracycline (63.63%), and clindamycin (50.9%). On the other hand, there was the highest susceptibility for ciprofloxacin (100%) followed by gentamycin (90.91%) and erythromycin (87.27%). Multidrug resistance was also found in 54 (98%) of the isolates. Conclusion. In this study highly drug-resistant S. aureus was incriminated as the main meat contaminant in butcheries of Bahir Dar city. Therefore, appropriate antimicrobial use and staphylococcal control methods should be employed to prevent S. aureus intoxications in foods.

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Isolation, antimicrobial susceptibility patterns, and risk factors assessment of non-typhoidal Salmonella from apparently healthy and diarrheic dogs

BMC Veterinary Research ◽

10.1186/s12917-021-03135-x ◽

2022 ◽

Vol 18 (1) ◽

Author(s):

Belisa Usmael ◽

Bruk Abraha ◽

Sisay Alemu ◽

Bahar Mummed ◽

Adem Hiko ◽

...

Keyword(s):

Risk Factors ◽

Antimicrobial Resistance ◽

Rectal Swab ◽

Bacterial Load ◽

Diffusion Method ◽

Resistance Pattern ◽

Biochemical Tests ◽

Disk Diffusion Method ◽

Eastern Ethiopia ◽

Apparently Healthy

Abstract Background Dogs are one of the important asymptomatic carriers of antimicrobial resistant and potentially pathogenic strains of Salmonella. They can harbor large bacterial load in the intestines and mesenteric lymph nodes which can be shed in their feces with the possibility of transmission to humans. Therefore, a cross-sectional study was conducted with the objectives of estimating the prevalence of non-typhoidal Salmonella, assessing the risk factors for dog’s Salmonella carriage, and profiling the antimicrobial resistance pattern of Salmonella isolates among housed dogs in Harar town, Eastern Ethiopia. A total of 415 rectal swab samples were collected from randomly selected dogs. Samples were examined for non-typhoidal Salmonella using standard bacteriologic culture and biochemical tests. The disk diffusion method (Kirby-Bauer test) was employed to evaluate the isolates for their susceptibility against five antimicrobials. Results Non-typhoidal Salmonella were isolated from 26 (6.3%) of the rectal swab samples, with significantly higher occurrence in diarrheic (15.2%) than non-diarrheic (5.5%) dogs. The risk of Salmonella harboring was significantly higher in female dogs than in male dogs (OR = 2.5, p = 0.027). Dogs fecal shedding of Salmonella was relatively higher in households who used offal as a main feed type for their dogs (23.1%; 95% CI = 5–53.8) than those who used leftover food (10.1%; 95% CI = 5.7–16.1) and practiced mixed feeding system (17%; 95% CI = 7.6–30.8). Salmonella isolates showed higher resistance to ampicillin (41.7%), while all isolates were fully susceptible to gentamicin. Moreover, 58.3% of Salmonella isolates showed resistance to at least one of the tested antimicrobials. Majorities (72.7%) of the dog owners had no awareness on the risk of zoonotic salmonellosis from dog and all of the respondents use bare hand to clean dog kennel. Conclusion Our study reveals the importance of both diarrheic and apparently healthy housed dogs in the harboring and shedding of antimicrobial resistant non-typhoidal Salmonella. The risk of non-typhoidal Salmonella spread among pet owners is not negligible, especially in households who use offal as main feed type. Therefore, an integrated approach such as: proper dog handling practices; continuous evaluation of antimicrobial resistance; and rational use of antimicrobials in the field of veterinary sector are necessary to tackle the problem.

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Methicillin-resistant Staphylococcus aureus bloodstream infection: risk factors and clinical outcome in non-intensive-care units

Revista da Sociedade Brasileira de Medicina Tropical ◽

10.1590/s0037-86822012000200010 ◽

2012 ◽

Vol 45 (2) ◽

pp. 189-193 ◽

Cited By ~ 4

Author(s):

Karinne Spirandelli Carvalho Naves ◽

Natália Vaz da Trindade ◽

Paulo Pinto Gontijo Filho

Keyword(s):

Risk Factors ◽

Staphylococcus Aureus ◽

Bloodstream Infection ◽

Antimicrobial Agents ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Methicillin Resistant ◽

Staphylococcus Aureus Bloodstream Infection

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) is spread out in hospitals across different regions of the world and is regarded as the major agent of nosocomial infections, causing infections such as skin and soft tissue pneumonia and sepsis. The aim of this study was to identify risk factors for methicillin-resistance in Staphylococcus aureus bloodstream infection (BSI) and the predictive factors for death. METHODS: A retrospective cohort of fifty-one patients presenting bacteraemia due to S. aureus between September 2006 and September 2008 was analysed. Staphylococcu aureus samples were obtained from blood cultures performed by clinical hospital microbiology laboratory from the Uberlândia Federal University. Methicillinresistance was determined by growth on oxacillin screen agar and antimicrobial susceptibility by means of the disk diffusion method. RESULTS: We found similar numbers of MRSA (56.8%) and methicillin-susceptible Staphylococcus aureus (MSSA) (43.2%) infections, and the overall hospital mortality ratio was 47%, predominantly in MRSA group (70.8% vs. 29.2%) (p=0.05). Age (p=0.02) was significantly higher in MRSA patients as also was the use of central venous catheter (p=0.02). The use of two or more antimicrobial agents (p=0.03) and the length of hospital stay prior to bacteraemia superior to seven days (p=0.006) were associated with mortality. High odds ratio value was observed in cardiopathy as comorbidity. CONCLUSIONS: Despite several risk factors associated with MRSA and MSSA infection, the use of two or more antimicrobial agents was the unique independent variable associated with mortality.

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Prevalence, Risk Factors, and Antibiogram of Nontyphoidal Salmonella from Beef in Ambo and Holeta Towns, Oromia Region, Ethiopia

International Journal of Microbiology ◽

10.1155/2021/6626373 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Endrias Zewdu Gebremedhin ◽

Gezahegn Tafesse Soboka ◽

Bizunesh Mideksa Borana ◽

Lencho Megersa Marami ◽

Edilu Jorga Sarba ◽

...

Keyword(s):

Risk Factors ◽

Food Safety ◽

Antimicrobial Susceptibility ◽

Multidrug Resistant ◽

Animal Origin ◽

Diffusion Method ◽

Isolation And Identification ◽

Disk Diffusion Method ◽

Cross Sectional ◽

Food Of Animal Origin

Background. Salmonella has been recognized as a major cause of food-borne illness associated with the consumption of food of animal origin. The present cross-sectional study was conducted from December 2017 to May 2018 in Ambo and Holeta towns to assess the prevalence, risk factors, and antimicrobial susceptibility patterns of nontyphoidal Salmonella isolates from raw beef samples from abattoirs, butchers, and restaurants in Ambo and Holeta towns, Oromia region, Ethiopia. Methods. A total of 354 beef samples were collected from abattoirs, butchers, and restaurants. Salmonella isolation and identification were carried out using standard bacteriological methods recommended by the International Organization for Standardization. Antimicrobial susceptibility testing was performed using the disk diffusion method. Besides, a structured questionnaire was used to collect sociodemographic data and potential risk factors for contamination of meat. Chi-square tests and logistic regression were used for data analyses. Results. Of the total 354 meat samples examined, 20 (5.7%, 95% confidence interval (CI): 3.5–8.6) were positive for Salmonella. Two serotypes belonging to S. typhimurium (11 isolates) and I:4,5,12: i:- (9 isolates) were identified. The Salmonella detection rate in abattoirs, butchers, and restaurants was 4.2% (5/118), 8.5% (10/118), and 4.2% (5/118), respectively. The antimicrobial susceptibility test showed that 40%, 30%, and 20% of the Salmonella isolates were resistant to azithromycin, amoxicillin, and ceftriaxone, respectively. The odds of Salmonella isolation when meat handlers are illiterate were 7.8 times higher than those when they are educated to the level of secondary and above ( P = 0.032 ). Similarly, the likelihood of Salmonella isolation was 6.3 and 7.6 times higher among workers of butcher and restaurants, respectively, who had no training ( P = 0.003 ) and no knowledge ( P = 0.010 ) on food safety and hygiene. Conclusions. The study showed widespread multidrug-resistant Salmonella isolates in the study areas. Therefore, raw meat consumption and indiscriminate use of antimicrobial drugs should be discouraged. Provision of food safety education for meat handlers and further surveillance of antimicrobial-resistant isolates are suggested.

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Prevalence and risk factors associated with Campylobacter among layer farms

Veterinary Science Development ◽

10.4081/vsd.2018.6430 ◽

2018 ◽

Vol 8 (1) ◽

Cited By ~ 1

Author(s):

Mohammad Q. Al-Natour ◽

Akram R. Al-Aboudi ◽

Musa A. Alshehabat ◽

MT K. Tamimi

Keyword(s):

Risk Factors ◽

Stocking Density ◽

Occurrence Rate ◽

Residual Chlorine ◽

Public Health Importance ◽

Factors Associated ◽

Poultry Products ◽

Food Borne ◽

Potential Risk Factors ◽

Free Residual Chlorine

Campylobacter jejuni is an important food-borne pathogen. The main source of this pathogen is poultry and poultry products. Poultry farms of low biosecurity level plays major role in disseminating this pathogen. The objectives of this study were to investigate the occurrence of Campylobacter and identify potential risk factors associated with their presence in layer farms in Northern Jordan. A total of 2524 samples from chickens, litter, water and feed were collected from 35-layer farms. Samples underwent conventional and enrichment isolation methods for Campylobacter. Confirmation was done morphologically, biochemically and by PCR typing. The flock-level prevalence of C. jejuni was 40%, 37%, 20% in chicken cloacae, drinking water and litter respectively. C. jejuni was the only confirmed isolated species. None of the feed samples revealed presence of Campylobacter. The concentration of free residual chlorine was below the recommended standard levels. The risk factors were identified using modified semi-structured questionnaire. There was no significant association between evaluated risk factors and isolation status potentially reflecting small number of study farms. The prevalence rate for C. jejuni is within commonly reported range. High stocking density, short distance between farms, improper hygienic practice and low water chlorine level seems to increase occurrence rate of Campylobacter in layer farms. Educational biosecurity programs regarding C. jejuni transmission and their public health importance needs to be established.

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Detection of Pan drug resistance OXA-48 producing Providencia in an ICU patient for the first time in Nepal

Antimicrobial Resistance and Infection Control ◽

10.1186/s13756-019-0608-1 ◽

2019 ◽

Vol 8 (1) ◽

Cited By ~ 3

Author(s):

Ranjit Sah ◽

Shusila Khadka ◽

Gentle Sunder Shrestha ◽

Subhash Acharya ◽

Diptesh Aryal ◽

...

Keyword(s):

Drug Resistance ◽

Pathogenic Bacteria ◽

Antimicrobial Agents ◽

Vital Signs ◽

Carbapenem Resistance ◽

Diffusion Method ◽

Resistance Pattern ◽

Common Mechanism ◽

Disk Diffusion Method ◽

Drug Resistance Pattern

Abstracts Background Resistance to antimicrobial agents of pathogenic bacteria has become a major problem in routine medical practices. Carbapenem resistance has long been increasing. The production of carbapenem- hydrolysing β-lactamases (carbapenamases), which include NDM, KPC, OXA-48, IMP-1 and VIM is the most common mechanism. Case presentation A 56 years old male presented with fever and mental changes with progressively decreasing sensorium for the last 3 days. He was admitted to Intensive care unit (ICU) with a diagnosis of meningoencephalitis. On day seven, he developed ventilator associated pneumonia due Klebsiella pnemoniae and Acinetobacter baumannii. He was on meropenem, but the isolates were susceptible to colistin, tigecyclin and amikacin solely. Hence, amikacin was started with addition of intravenous and nebulized colistin. Subsequently, vital signs improved with resolution of fever. However, on day 18, he developed fever once again with a drop in blood pressure. Inotropic support was maintained, and echinocandins and tigecycline were added to the regimen. Repeat blood and urine culture grew Providencia species, which were resistant to most of the drugs on phenotypic Kirby-Bauer disk diffusion method and are intrinsically resistant to colistin and tigecycline. Phenotypic detection of ESBL (combined disk method), MBL, KPCs, AmpC and co-producer were tested according to updated CLSI guideline and all were negative. But the Modified Hodges test was found to be positive. Consequenty, OXA-48 drug resistance pattern was brought into action by blank disc method according to A Tsakris et al., which revealed indentation of growth toward both EDTA and EDTA/PBA disk indicating production of OXA-48 carbapenamase. To confirm the resistance pattern we processed the isolated colonies for Xpert Carba-R (Cepheid) assay, which detected blaOXA-48 gene and confirmed the OXA-48 drug resistance pattern. Hence, the infecting organism was not susceptible to any of the antibiotics. The patient was kept under isolation and on 31th day of admission, he died of septic shock. Conclusions Carbapenamase production along with intrinsic colistin resistance in infecting bacterial pathogens can cause fatal outcomes in the resource limited countries like Nepal where new antibiotic combinations ceftazidime+ Avibactam, or aztreonam +avibactam are not available. Drug resistance patterns including OXA 48 producer should be characterized in all cases by standard phenotypic methods or by Xpert Carba-R assay and larger studies are required to know the exact burden of OXA 48 producer in Nepal.

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Streptococcus agalactiae in pregnant women: serotype and antimicrobial susceptibility patterns over five years in Eastern Sicily (Italy)

European Journal of Clinical Microbiology & Infectious Diseases ◽

10.1007/s10096-020-03992-8 ◽

2020 ◽

Vol 39 (12) ◽

pp. 2387-2396

Author(s):

Carlo Genovese ◽

Floriana D’Angeli ◽

Valentina Di Salvatore ◽

Gianna Tempera ◽

Daria Nicolosi

Keyword(s):

Pregnant Women ◽

Antimicrobial Susceptibility ◽

Streptococcus Agalactiae ◽

Late Onset ◽

Disk Diffusion ◽

Diffusion Method ◽

Resistance Pattern ◽

Disk Diffusion Method ◽

Defibrinated Sheep Blood ◽

Disk Diffusion Test

AbstractStreptococcus agalactiae (also known Group B Streptococcus or GBS) represents the main pathogen responsible for early- and late-onset infections in newborns. The present study aimed to determine the antimicrobial susceptibility pattern and the capsular serotypes of GBS isolated in Eastern Sicily over 5 years, from January 2015 to December 2019. A total of 3494 GBS were isolated from vaginal swabs of pregnant women (37–39 weeks), as recommended by the Centers for Disease Control and Prevention. Capsular polysaccharide’s typing of GBS was determined by a commercial latex agglutination test containing reagents to serotypes I–IX. The antimicrobial resistance pattern of GBS was determined through the disk diffusion method (Kirby-Bauer) and the double-disk diffusion test on Mueller-Hinton agar plates supplemented with 5% defibrinated sheep blood, according to the guidelines of the Clinical and Laboratory Standards Institute. Serotypes III (1218, 34.9%) and V (1069, 30.6%) were the prevalent colonizers, followed by not typable (570, 16.3%) and serotypes Ia (548, 15.7%), Ib (47, 1.3%), II (40, 1.1%), and IV (2, 0.1%). All 3494 clinical isolates were susceptible to cefditoren and vancomycin. Resistance to penicillin, ampicillin, levofloxacin, clindamycin, and erythromycin was observed in 6 (0.2%), 5 (0.1%), 161 (4.6%), 1090 (31.2%), and 1402 (40.1%) of the strains, respectively. Most of erythromycin-resistant GBS (1090/1402) showed the cMLSB phenotype, 276 the M phenotype, and 36 the iMLSB phenotype. Our findings revealed a higher prevalence of serotype III and a relevant resistance rate, among GBS strains, to the most frequently used antibiotics in antenatal screening.

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Antibiotic Resistance ofSalmonellaspp. Isolated from Shrimp Farming Freshwater Environment in Northeast Region of Brazil

Journal of Pathogens ◽

10.1155/2013/685193 ◽

2013 ◽

Vol 2013 ◽

pp. 1-5 ◽

Cited By ~ 11

Author(s):

Fátima C. T. Carvalho ◽

Oscarina V. Sousa ◽

Edirsana M. R. Carvalho ◽

Ernesto Hofer ◽

Regine H. S. F. Vieira

Keyword(s):

Drug Resistance ◽

Antibiotic Resistance ◽

Shrimp Farming ◽

Diffusion Method ◽

Resistance Pattern ◽

Plasmid Curing ◽

Freshwater Environment ◽

Disk Diffusion Method ◽

Northeast Region ◽

Drug Resistance Pattern

This study investigated the presence and antibiotic resistance ofSalmonellaspp. in a shrimp farming environment in Northeast Region of Brazil. Samples of water and sediments from two farms rearing freshwater-acclimatedLitopenaeus vannameiwere examined for the presence ofSalmonella. Afterwards,Salmonellaisolates were serotyped, the antimicrobial resistance was determined by a disk diffusion method, and the plasmid curing was performed for resistant isolates. A total of 30 (16.12%) of the 186 isolates were confirmed to beSalmonellaspp., belonging to five serovars:S. serovar Saintpaul,S. serovar Infantis,S. serovar Panama,S. serovar Madelia, andS. serovar Braenderup, along with 2 subspecies:S. entericaserovar houtenae andS. entericaserovar enterica. About twenty-three percent of the isolates were resistant to at least one antibiotic, and twenty percent were resistant to at least two antibiotics. Three strains isolated from water samples (pond and inlet canal) exhibited multiresistance to ampicillin, tetracycline, oxytetracycline, and nitrofurantoin. One of them had a plasmid with genes conferring resistance to nitrofurantoin and ampicillin. The incidence of bacteria pathogenic to humans in a shrimp farming environment, as well as their drug-resistance pattern revealed in this study, emphasizes the need for a more rigorous attention to this area.

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Inhibitory activity of crude bacteriocin produced by lactic acid bacteria isolated from dadih against Listeria monocytogenes

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d210404 ◽

2020 ◽

Vol 21 (4) ◽

Author(s):

Usman Pato ◽

YUSMARINI YUSUF ◽

SHANTI FITRIANI ◽

NIA NAIDYA JONNADI ◽

MIMI SRI WAHYUNI ◽

...

Keyword(s):

Antimicrobial Activity ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Inhibition Zone ◽

Diffusion Method ◽

Antimicrobial Compounds ◽

Disk Diffusion Method ◽

Food Borne ◽

Paper Disk ◽

Natural Preservatives

The use of natural preservatives called bacteriocin derived from lactic acid bacteria (LAB) is one way of preventing food from being contaminated by pathogenic microorganisms such as L. monocytogenes (LM). The aims of this study were to evaluate the ability of LAB isolated from dadih to inhibit the growth of LM and to obtain the antimicrobial components that play a role in inhibiting the growth of LM. The antimicrobial activity of the supernatant obtained from 12 strains of dadih LAB was determined using the paper disk diffusion method. The results showed that the supernatant from the 12 LAB strains was able to inhibit the growth of LM with various inhibition zones. However, out of the 12 LABs, only 9 strains were found to have an inhibition zone of more than 3.5 mm. The antimicrobial compounds of 9 strains were tested and it was found that the antimicrobial compounds of strains R-8, R-14 and R-49 were derived from lactic acid. In addition, 6 strains namely R-43, R-32, R-19, R-55, R-45 and R-41 were derived from bacteriocin based on their sensitivity to pH, heat and enzyme treatments. Crude bacteriocin derived from 6 LAB strains inhibited the growth of LM, and the highest antimicrobial activity was obtained in Streptococcus faecalis subsp. liquefaciens R-55 with an average inhibition zone of 13.87 mm. Bacteriocin produced by strain R-55 can be used as natural preservatives for the prevention of food-borne disease caused by LM.

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