Phages as Deodorants

Abstract

Although sweat from sweat glands is odourless, anaerobic bacteria from the genus Corynebacterium, Propionibacterium, Staphylococcus, and Micrococcus, which colonise human skin, especially in the armpit, generate chemical compounds when they metabolise sweat. This gives sweat an unpleasant odour, a problem to which deodorants are the most common solution. However, deodorants may cause irritation for some users and have an adverse impact on the skin. Alternative methods offer hope for sweat malodour. For instance, phages and their gene products may eliminate odour-causing bacteria as an alternative to chemical-based deodorants. This project examined the hypothesis that phages could provide an alternative to conventional deodorants by eliminating the bacteria that cause body odour. Specifically, the aim was to isolate the bacteria that cause odour and the phages that could infect them. The methodology involved normal microbiology and phage biology techniques, wherein the isolated bacteria were identified, and the isolated phages were characterised. Twelve anaerobic bacteria were isolated from human skin samples and identified by Autof MS1000 MALDI-Tof. A specific phage, termed Phage S, was also isolated from the human epidermis, and its lytic activity against Staphylococcus cohnii isolates was demonstrated. The maximum lytic activity of Phage S was observed between 35 and 37°C, and the optimal storage temperature was 4°C. Phage S showed a high burst size with a short latent period. In addition, it effectively inhibited bacterial growth as measured by a killing curve assay. The properties and efficient microbial growth suppression of Phage S against Staphylococcus cohnii indicate its potential for phage therapy against odour-causing bacteria.