1887

Abstract

Bacterial spores are of concern in food processing due to their ubiquity and resistance. This study seeks to determine the effect of ultraviolet C (UV-C) in the inactivation of spores of and that can result in enzymatic spoilage in foods using PBS as the suspension medium. Purified spore samples were treated under 1 pass in a UV-C reactor using 10 mL of spore inoculum with one dose of the radiation (410 mJ/cm2) for 10secs at room temperature. Aliquots of the treated samples were plated on tryptone soy agar supplemented with 0.6% glucose and the colonies counted. Flow cytometry analysis was done using 500 μL of both treated and control samples with a cell concentration of a ≥106 CFU/ml with propidium iodide (15 μM) and SYTO 9 (500 nM) used as live/dead stains. Samples were processed for microscopy (SEM and Raman-AFM Imaging). The maximum lethality is 2.5 for and the minimum is 0.1 for . Microscopic imaging of treated spores shows significant morphological disruption of the spore structure. The Raman spectroscopy analysis reveals the isolates to have the highest concentrations of dipicolnic acid (Ca+2DPA) as well as other compounds belonging to other functional groups. Flow cytometric analysis of treated spores reveals sub-populations unaccounted for by plate count. UV-C shows a promising application in the inactivation of resistant spores during processing of liquid foods such as milk.

Loading

Article metrics loading...

/content/journal/acmi/10.1099/acmi.ac2020.po0012
2020-07-10
2020-10-20
Loading full text...

Full text loading...

http://instance.metastore.ingenta.com/content/journal/acmi/10.1099/acmi.ac2020.po0012
Loading

Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error