Escherichia coli mtcc 40

The pure culture of each isolate was grown in MRS broth for 24 h and cell free supernatant (CFS) was obtained by centrifuging at 10,000 rpm, 4 °C, for 10 min. The collected CFS was checked for their antibacterial activity against Enterococcus faecalis MTCC 439, Shigella flexneri MTCC 1457, Aeromonas hydrophila MTCC 1739, Escherichia coli MTCC 40, Pseudomonas aeruginosa MTCC 4679, Staphylococcus aureus MTCC 737, Klebsiella pneumonaie MTCC 39, and Proteus vulgaris MTCC 426 received from Microbial Type Culture Collection (MTCC), Chandigarh, India and clinical pathogens such as P. aeruginosa, K. pneumoniae, Acinetobacter baumannii, methicillin resistant S. aureus (MRSA) received from Mahathma Gandhi Memorial Government Hospital, Tiruchirappalli, Tamil Nadu, India. The assay was performed by well diffusion method using 50 µL of each indicator bacteria (2.1 × 10⁵ CFU/mL).

Staphylococcus aureus MTCC 96, Escherichia coli MTCC 40 and Candida albicans MTCC 227 were purchased from Microbial Type Culture Collection, CSIR-Institute of Microbial Technology, Chandigarh, India, and the methicillin-resistant Staphylococcus aureus (MRSA) ATCC 43300 was purchased from HiMedia. Two clinical bacterial isolates (CL1 and CL2) were also obtained from Microbiology Department, Guwahati Neurological Research Center (GNRC), Guwahati, Assam for the evaluation of the antimicrobial assay. These two clinical isolates belonged to Staphylococcus saprophyticus and Bacillus pumillus, respectively, as determined by their 16S rRNA gene sequencing (date not shown). The antibiotic sensitivity pattern of the two clinical isolates was checked against 12 antibiotics using antibiotic-impregnated disc procured from HiMedia (data not shown). The test bacterial strains were cultured in Nutrient Agar (NA) medium (M001, HiMedia) at 37 °C while C. albicans was cultured in Sabouraud Dextrose Agar (SDA) medium (M063, HiMedia) at 28 °C. All the test microbial strains were preserved at − 80 °C in 20% (v/v) glycerol as stock cultures.