Abstract. Ansharieta R, Ramandinianto SC, Effendi MH, Plumeriastuti H. 2021. Molecular identification of blaCTX-M and blaTEM genes encoding extended-spectrum ß-lactamase (ESBL) producing Escherichia coli isolated from raw cow’s milk in East Java, Indonesia. Biodiversitas 22: 1600-1605. The emergence of extended-spectrum ?-lactamase (ESBL) producing bacteria and its increasing level has become public health issue. The presence of these bacteria in food of animal origin is quite alarming. The objective of this study was to detect and characterize Escherichia coli producing ESBL encoding genes, isolated from 200 raw cow milk samples in East Java, Indonesia. The results of this study showed that 70.5% of isolates were confirmed as E. coli, based on the morphological growth of colonies on the EMB Agar and biochemical IMViC tests. In this study, the double-disc synergy test (DDST) method was used to confirm the ESBL, and previously sorted out presumptively by using Aztreonam antibiotic disc. The antibiotics used were amoxicillin-clavulanate, ceftazidime, and cefotaxime for DDST. In addition, ESBL confirmation with Multiplex PCR method for blaCTX-M and blaTEM genes were done. The presence of ESBL-producing by E. coli isolated from raw cow’s milk in East Java were 2.12% (3/141). The PCR results showed that the double blaCTX-M and blaTEM gene harbored by 2 ESBL isolates and one blaTEM gene as many as 1 ESBL isolate. Thus, the findings of our study indicate that milk can be a good reservoir of bacteria carrying blaCTX-M and blaTEM ESBL resistance genes with the potential to affect human health.

Background and Aim: Raw milk can be a source of food-borne disease transmission and a medium for spreading antibiotic-resistant bacteria. Staphylococcus aureus and Escherichia coli are bacteria that have the pathogenic ability to attack host cells and are capable of harboring antibiotic-resistant genes. This study estimated the prevalence and antibiotic resistance of S. aureus and E. coli isolated from raw milk in East Java, Indonesia. Materials and Methods: Two hundred and fifty raw milk samples were collected from five dairy farms in East Java. S. aureus and E. coli were isolated using their respective selective media, whereas antibiotic susceptibility testing was performed using the Kirby–Bauer disk diffusion method. The methicillin-resistant S. aureus (MRSA) was confirmed using the oxacillin resistance screen agar test, and extended-spectrum beta-lactamase (ESBL)-producing E. coli was determined using the double-disk synergy test. The presence of mecA and blaTEM genes were screened by the polymerase chain reaction method. Results: Results indicated that the prevalence of S. aureus was 138 (55.2%) and that E. coli was 176 (70.4%). Of the 138 S. aureus isolated, 27 (19.6%) were MRSA, and among the 176 E. coli isolates identified, 3 (1.7%) were ESBL producers. The mecA gene was observed in 2 (7.4%) MRSA and all 3 (100%) ESBL-producing E. coli isolated harbored blaTEM genes. Conclusion: The presence of MRSA and ESBL-producing E. coli in raw milk is a serious public health threat, and public awareness should be raised about the dangers posed by these pathogenic organisms.

Escherichia coli is one of bacteria which have resistant to three or more classes of antimicrobial agents. E. coli having resistant to three or more classes of antimicrobial drugs can be defined as multidrug-resistant (MDR) bacteria. The aim of the study was to evaluate the expression of Shiga toxin gen in MDR E. coli. A total of 250 raw milks samples were taken from dairy farms in Kediri,