Vol. 11, Special Issue 3 (2022)

Author(s):
Poonam Shakya, Anju Nayak, RK Sharma, AP Singh, RV Singh, Joycee Jogi, Ajay Rai, Smita Bordoloi, Himani K, Aishwarya Lade and Rahul Sehar

Abstract:
Biofilms are structured aggregation of surface attached microbes encased in an extracellular matrix. Biofilm formation by resistant organisms like Methicillin Resistant Staphylococcus aureus makes the problem more difficult to treat. Hence, methods to detect the biofilm production by these resistant organisms is the need of the hour so that timely preventive measures can be taken. The study was conducted with the aim to detect the capability to form biofilm by 20 MRSA organisms isolated form cases of bovine mastitis which is the leading cause of decline in milk production in the dairy industry. Biofilm formation was detected by Congo Red agar method, Tube method and Microtitre plate assay. By Congo Red agar method, 05/20 (25%) isolates produced characteristic black coloured biofilm forming colonies and rest 15/20 (75%) isolates produced pink coloured non biofilm forming colonies. By Tube method, 07/20 (35%) isolates were weak biofilm producers, 05/20 (25%) isolates were moderate biofilm producers, 05/20 (25%) isolates were strong biofilm producers, while rest of the 03/20 (15%) isolates were designated as Non biofilm producers. Quantitative detection of biofilm was done by Microtitre plate method. The result was analysed by taking OD in ELISA reader at 570 nm. After 24 hours of incubation, results indicated that only 09/20 (45%) isolates were biofilm producers, which only produced weak biofilms. Rest 11/20 (55%) isolates were non biofilm forming. However, we can conclude from our study that the Tissue Culture Plate method is a more quantitative and reliable method for the detection of biofilm forming microorganisms as compared to Tube Method and Congo Red Agar methods and it can be recommended as a general screening method for detection of biofilm producing bacteria in laboratories.