Antarctic bacteria inhibit growth of food-borne microorganisms at low temperatures

• Published in: FEMS Microbiology Ecology
• Main Authors: O'Brien, Andrea, Sharp, Richard, Russell, Nicholas J., Roller, Sibel
• Format: Text
• Language: English
• Published: Oxford University Press 2004
• Subjects: Articles; Antarctic; Antarc*
• Online Access: http://femsec.oxfordjournals.org/cgi/content/short/48/2/157; https://doi.org/10.1016/j.femsec.2004.01.001

The aim of this study was to identify Antarctic microorganisms with the ability to produce cold-active antimicrobial compounds with potential for use in chilled food preservation. Colonies (4496) were isolated from 12 Antarctic soil samples and tested against Listeria innocua , Pseudomonas fragi and Brochothrix thermosphacta . Thirteen bacteria were confirmed as being growth-inhibitor producers (detection rate 0.29%). When tested against a wider spectrum of eight target organisms, some of the isolates also inhibited the growth of L. monocytogenes and Staphylococcus aureus . Six inhibitor producers were psychrotrophic (growth optima between 18 and 24 °C), halotolerant (up to 10% NaCl) and catalase-positive; all but one were Gram-positive and oxidase-positive. The inhibitors produced by four bacteria were sensitive to proteases, suggesting a proteinaceous nature. Four of the inhibitor–producers were shown to be species of Arthrobacter , Planococcus and Pseudomonas on the basis of their 16S rRNA gene sequences and fatty acid compositions. It was concluded that Antarctic soils represent an untapped reservoir of novel, cold-active antimicrobial-producers.