ObjectiveFood-borne pathogens are a major cause of illnesses, death and expenses. Their occurrence in meat and other food is considered a global health problem. The burden of food-borne disease is increasing due to antimicrobial resistance which represents a greater risk of treatment failure. However, very little is known about the antibiotic resistance profile of food-borne pathogens in Nepal. This study was conducted to examine the antibiotic resistance profile of common food-borne bacterial pathogens isolated from raw meat sold in Nepal. A total of 83 meat samples were collected from the market and analyzed.ResultsThe prevalence of Staphylococcus aureus, Escherichia coli, Salmonella, Shigella, and Vibrio were 68%, 53%, 35%, 6%, and 6% respectively. The resistance of Salmonella was most frequently observed to amoxicillin (100%), tetracycline (24%), chloramphenicol (11%), and nalidixic acid (11%). S. aureus was resistant to amoxicillin (100%) followed by tetracycline (63%), nalidixic acid (17%), and cefotaxime (13%) respectively. Vibrio isolates resisted amoxicillin (100%), tetracycline (40%) and chloramphenicol (20%). Shigella expressed the highest resistance to amoxicillin (100%), followed by chloramphenicol (80%), tetracycline (60%) and nalidixic acid (20%). E. coli exhibited the highest resistance to amoxicillin (100%), followed by tetracycline (93%), nalidixic acid (25%) and cefotaxime (19%).

Background: Escherichia coli is the most common causative agent of urinary tract infection. Antibiotic resistance among uropathogens has become a prominent public health problem. Multidrug resistance bacteria have limited the therapeutic possibilities by producing Extended Spectrum Beta Lactamases (ESBL). Objective: Since routine monitoring of ESBL producers are not conducted in clinical laboratories their true prevalence is still unknown. So the objective of this research was to assess multiple antibiotic resistance (MAR) indices and determine ESBL production among Escherichia coli isolated from urine samples. Methods: Standard microbiological techniques and antibiotic sensitivity test were performed by Kirby Bauer disc diffusion method to identify E. coli. ESBL screening was done by using Ceftriaxone, Aztreonam, Cefotaxime, Ceftazidime and Cefpodoxime whereas confirmation by combined disc assay. SPSS 16 software was used to analyze data. Results: 86.95% E. coli isolates were MDR strains. 27 isolates had multiple antibiotic resistance (MAR) index of 0.2 and 5 isolates had MAR index of 0.7. E. coli isolates showed higher degree of resistance towards Amoxicillin (100%) while 100% were sensitive towards Gentamicin followed by Nitrofurantoin (62.31%). The reliable screening agent for ESBL detection with sensitivity 100% and positive predictive value of 80% was Cefotaxime. Combined disc assay detected 12/69 (17.31%) of E. coli isolates as confirmed ESBL producers. Conclusion: The ubiquity of ESBL-producing E. coli was observed emphasizing the necessity of regular surveillance of ESBL producing clinical isolates in clinical samples to minimize multi-drug resistance strains and avert the ineffectiveness of antimicrobial agent for good health practices.\Int J Appl Sci Biotechnol, Vol 3(3): 423-426

Milk is an excellent medium for the growth of many bacteria. This study aimed to determine antibiotic profiling and thermal inactivation of Staphylococcus aureus and Escherichia coli isolated from raw milk of Dharan. Total viable count, total Staphylococcal count, and total coliform count were carried out by conventional microbiological methods. Identification was done on the basis of Gram staining and biochemical tests. The antibiotic susceptibility test of the isolates carried out by the modified Kirby-Baur disc diffusion method. Thermal inactivation of S. aureus and E. coli were carried out by subjecting to thermal treatment in a water bath. Total plate count ranged from 204×104 CFU/mL to 332×105 CFU/mL. Total staphylococcal count and total coliform count ranged from 14×105 CFU/mL to 8×106 CFU/mL and 11×104 CFU/mL to 3×106 CFU/mL respectively. S. aureus showed an increasing resistance patterns towards Ampicillin, Cefotixin, Carbenicillin and Cefotaxime. Ciprofloxacin, Erythromycin, Amikacin, Gentamycin, Azithromycin, and Chloramphenicol were found to be effective against S. aureus. All the E. coli isolates were resistant to Ampicillin and least resistant to Cefotixin. Chloramphenicol, Amikacin, Azithromycin, and Nalidixic acid were found highly effective to E. coli. The D-values for S. aureus at 56°C, 58°C and 60°C were 1.36 min, 1.19 min, and 1.09 min respectively. The Z-value was 14.92°C. While D-values were obtained as 0.98 min, 0.75 min, and 0.57 min for E. coli at 56° C, 58° C and 60° C respectively, and Z-value was 9.75° C. Hence, S. aureus was found to be more heat resistant than E. coli.

Background Staphylococcus aureus is one of the common cause of hospital acquired infection and community acquired infections. Nowadays these organisms became resistant towards variety of drugs. MRSA is the emerging antibiotic resistant bacteria that are resistant to methicillin antibiotic and known to be the infectious pathogen causing severe infection and a cause of fatal mortality.Materials and methodology Altogether 200 nasal swabs and 200 hand swabs were obtained from participants and transported to microbiology lab in cold chain. The samples were swabbed in mannitol salt agar (MSA) containing oxacillin powder of 6mg/L and incubated at 37°C for 24 hrs. Staphylococcus aureus colonies were identified based on growth characteristics on MSA plates (golden yellow colonies), Gram stain and positive results for coagulase tube test and catalase test. The pure isolated MRSA were subjected to antibiotic susceptibility tests and biofilm formation assays.Results From our study the overall prevalence of CA-MRSA was 61.5%. Higher frequency of multi-drug resistant MRSA was isolated. The biofilm producing CA-MRSA were 51.2% which showed high drug resistance and rest (48.7%) were non-biofilm producers. There was significant association in biofilm production with multi-drug resistance (p<0.05). Ciprofloxacin was most sensitive drug against the isolates which was statistically significant (p<0.05). The resistant pattern of biofilm producers reported high ability of multi-drug resistance compared to non-biofilm producers (p<0.05). Microtitre plate method was found to be gold standard over tube and congo red agar method for screening biofilm formation. Surprisingly the emergence of VISA and VRSA strains were significantly reported from our study. The prevalence of VISA and VRSA among CA-MRSA was found to be 49.5% and 40.6% respectively among the isolates which indicates the failure of Vancomycin drug in clinical therapy.Conclusions The prevalence of CA-MRSA was found more in barbers followed by beauticians and municipal waste workers in comparison to healthy controls. This study reported the higher carriage of CA-MRSA in potential risk population along with emergence of VISA and VRSA strains. Improvement in personal hygiene and formulation of appropriate health policy helps to prevent CA-MRSA infection. This study concludes that CA-MRSA is still emerging with multi-drug resistance.

This study aimed to explore the distribution of non-sorbitol fermenting Escherichia coli (E. coli) from meat marketed in Dharan city and study its susceptibility to antibiotics. This study was the laboratory based cross-sectional study conducted from December 2016 to May 2017 at Microbiology laboratory of Central Campus of Technology. A total of 24 meat samples from butcher’s retail shop of Dharan were taken for study that included 6 chickens, 6 buffalo, 6 pork, and 6 goat meat sample. The bacterial isolates from meat samples were isolated by routine microbiological procedures and identified by colony characteristics on selective medium, Gram's staining and biochemical tests. The antibiotic susceptibility test (AST) of the isolated bacteria was performed by Kirby–Bauer disc diffusion method. Results reported 41.66% (10/24) prevalence of non-sorbitol fermenting E. coli in meat samples. However, this distribution was not statistically significant (p=0.877). The prevalence of E. coli was 3 (50%) in chicken, 3 (50%) in buffalo, 2 (33.33%) in pork and 2 (33.33%) in goat meat. All the isolated E. coli were subjected to the antibiotic susceptibility test using 17 different antibiotics and all the strains showed 100% resistance against ampicillin, amoxicillin and ceftazidime and the highest sensitivity towards gentamycin (90%), ceftriaxone (80%), amikacin (80%) and chloramphenicol (80%). The 100% multidrug resistance was observed in all the isolates. This study concludes that the meat consumers of Dharan are at higher risk of infection by pathogenic strain of E. coli. The increasing incidence of multi drug resistance of pathogenic strains may pose serious health ailment among semi-processed meat consumers whilst the cooked meat consumers too are at risk of toxin-mediated food poisoning.

Bio-surfactants are surface-active molecules which are produced by the wide range of microbes including bacteria, fungi, moulds, and yeast. This study was conducted to identify bio-surfactants by Bacillus subtilis combined with use of cheap substrates and industrial wastes (Mustard cake, Whey and Soya cake) which are found locally in Nepal. Bacillus subtilis, one of the most potential bio-surfactants producer; was isolated from soil sample of hydrocarbon contaminated site. Isolates were grown in a Minimal Salt Media (MSM) with 10% (v/v) mustard oil cake, whey and soya cake separately. The presence and potential of surfactant was determined by the oil spreading technique, emulsification index (%E24) and surface tension measurement. It was revealed that the surface tensions of cell free extract were 54.41, 60.02 and 56.64 mN/m for from mustard cake, whey and soya cake respectively as compared to distilled water (72.09) at 25oC. The emulsification index values was found to be highest in engine oil from the bio-surfactant extracted from mustard cake, soya cake and whey respectively. Similarly, mustard oil showed the lowest value of emulsification index. The highest emulsification activity was shown in mustard oil i.e. 1.13 from the cell free extract from mustard oil and lowest in engine oil i.e., 0.07, by the extract from soya cake medium, when measured in spectrophotometer at 540 nm. In conclusion, strain of Bacillus subtilis was found to be the potential surface active agent producers on the mustard oil cake, which can be useful medium for various environmental, food, medicinal and industrial processes.