Background and Aim:The feasibility assessment of food products on the market becomes one of the milestones of food safety. The quality of food safety of animal origin especially pork need to get attention and more real action from the parties related and concerned. Since pork is also a source of transmission for the contagion of foodborne disease so that the study of the existence of several agents in the pork and its products become the benchmark of safety level. This study aimed to isolate, identify, and detect the Shiga toxin 2a (stx2a) gene from Escherichia coli O157:H7 in pork, pig feces, and clean water in the Jagalan slaughterhouse.Materials and Methods:A total of 70 samples consisting of 32 pork samples, 32 pig fecal samples, and 6 clean water samples were used to isolate and identify E. coli O157:H7 and the stx2a gene. Isolation and identification of E. coli O157:H7 were performed using culture on eosin methylene blue agar and Sorbitol-MacConkey agar media and confirmed molecularly with polymerase chain reaction to amplify the target genes rfbE (317 bp) and fliC (381 bp). The isolates, which were identified as E. coli O157:H7, were investigated for the stx2a gene (553 bp).Results:The results of this study show that of the total collected samples, E. coli O157:H7 was 28.6% in Jagalan slaughterhouse and consisted of 25% of pork samples, 31.25% of pig fecal samples, and 33.3% of clean water samples. The isolates that were identified to be E. coli O157:H7 mostly contained the stx2a gene, which was equal to 75%, and consisted of seven isolates from pork samples, seven isolates from fecal samples, and one isolate from clean water samples.Conclusion:E. coli O157:H7 was found in 28.6% of pork, pig feces, and clean water in Jagalan slaughterhouse and 75% of identified E. coli O157:H7 contained the stx2a gene.

E scherichia coli O157:H7 is a subset of enterohemorrhagic E. coli (EHEC) that can cause diarrhea in human. Escherichia coli O157:H7 differ from normal flora found in the intestine and are categorized into specific group based on virulence factors, such as exotoxin (Fernandez, 2008). The EHEC produces Shiga-like toxin, it is also called Shiga toxin (stx)-producing E. coli (STEC). Stx consists of two subgroups, namely stx1 and stx2. Other virulence factors found in EHEC are eae (intimin), rfbE (O157 antigen), and fliC (flagellar antigen). EHEC lives research Article Abstract | Food products of animal origin, especially beef, are at risk of Escherichia coli (E. coli) contamination during slaughtering and/or processing that poses serious threat to consumers. E. coli contamination affects food quality because the pathogen contains toxins that can cause disease and even death. This study aimed to detect virulence genes in E. coli O157:H7 and non-O157 isolates of beef sold in the traditional markets of the Yogyakarta Special Province, Indonesia, using the multiplex polymerase chain reaction (multiplex PCR). A total of 98 raw beef samples were collected aseptically from different markets of study area and cultured on various selective media followed by the analysis by multiplex PCR amplification. The results exhibited that out of 98 beef samples, 83 (84,69%) were positive for E. coli. The main virulence genes detected were eae, fliC, rfbE, and stx2A. All of these virulence genes of E. coli O157:H7 were detected in all beef samples. The 28 isolates were identified as non-O157 E. coli that exhibited the eae gene, however they were not exhibited the rfbE and fliC genes. This study concluded the presence of significant contamination of virulent E. coli strains in beef meat sold in the Yogyakarta Special Province, Indonesia. Moreover, multiplex PCR assay was shown to be effective for the detection of E. coli O157:H7 and non-O157 strains from beef and may be applied for other food matrices as well.

Abstract. Indraswari A, Suardana IW, Haryanto A, Widiasih DA. 2021. Molecular analysis of pathogenic Escherichia coli isolated from cow meat in Yogyakarta, Indonesia using 16S rRNA gene. Biodiversitas 22: 4566-4573. Meat has been recognized as a major source of foodborne disease and a public health problem. The characteristics of meat become an ideal growth medium for various microorganisms if not handled properly. Pathogenic Escherichia coli is one of the foodborne disease agents that causes diarrhea. Identification of pathogenic E. coli isolated from cow meat needs to be done. This research aims to study nucleotide sequence of 16S rRNA gene of pathogenic E. coli isolated from cow meat in Yogyakarta, Indonesia using Polymerase Chain Reaction (PCR). These fifteen isolates have been detected for eae target gene, then amplification of the 16S rRNA gene was carried out using primers 27F and 1492R. Phylogenetic tree reconstruction was performed on the fifteen isolates of pathogenic E. coli to figure out the relationship to reference strains available at the GenBank. Results show that nucleotide sequence among the fifteen isolates from different traditional markets in Yogyakarta, Indonesia and reference strains are very similar. The fifteen isolates have small genetic distance to the reference strains, and these fifteen isolates are also in the same clade with reference strains. This research shows that the fifteen isolates under investigation are closely related to the reference strains, which is Shiga-toxin producing E. coli (STEC). People should pay more attention in processing food stock, especially cow meat. Further research may focus on determining the strain of those fifteen isolates.