Isolation of Klebsiella pneumoniae and Acinetobacter radioresistens from Dish Wash Scrubbers

Aims: To identify predominant microorganisms in dish washing scrubbers collected from ten different sources.

Study Design: Collection of dish wash scrubbers from different sources, pour plating of appropriately prepared dish wash scrub suspensions and subsequent isolation and identification of predominant isolates. Assessment of antibiotic susceptibility of the selected isolates by disc diffusion assay.

Place and Duration of Study: April, 2018 - June 2018.

Methodology: A total of 10 dish wash scrubbers (synthetic green scrubber pads free from any anti-bacterial preservatives belonging to the same brand) were collected from various sources. Appropriately prepared dish wash scrub suspensions in peptone water were pour plated on Plate Count Agar (PCA) and MacConkey agar. Predominant colonies selected from the plates based on the colony morphology were subjected to Grams staining, catalase, oxidase, indole, citrate, urease tests and genotypic identification by 16S ribosomal RNA sequencing. The identified isolates were tested for their susceptibility to eight antibiotics by disc diffusion method.

Results: Irrespective of the sample source, most of the dish wash scrubbers sampled harbored similar types of colonies. From the colonies obtained two of them were identified by 16S rRNA sequencing and subsequent blasting as Klebsiella pneumoniae and Acinetobacter radioresistens. The isolates were deposited in the NCBI database with accession numbers MK032217 (Klebsiella pneumoniae RSV02) and MK032134 (Acinetobacter radioresistens RSV 01). These isolates were tested for their susceptibility to different antibiotics and Acinetobacter radioresistens RSV 01 was found to be more antibiotic susceptible than Klebsiella pneumoniae RSV02.

Conclusion: Observations of this study confirm the potential role of dish wash scrubbers as vehicle for potential pathogens and their ability to act as cross contaminating agents in food processing environments.