Comparative study of Salmonella Typhimurium biofilms and their resistance depending on cellulose secretion and maturation temperatures
Soo-Hwan Kim, Sunna Jyung, Dong‐Hyun Kang
Abstract
We investigated the aspects of S. Typhimurium biofilms and their resistance (thermal and chemical) depending on the different morphotypes at room temperature (rdar; strain 43971 and bdar; strain 19585) and maturation temperature. Strain 19585 biofilm had a relatively low cell mass and polysaccharide content compared to strain 43971 in all cases, and when matured for 9 days at 15 °C, both properties were significantly higher than at 25 and 37 °C maturation. The difference in secretion ability influenced the pattern in which the biofilm increased resistance. The thermal and chemical resistance levels of strain 19585 biofilms increased at 15 °C, and those of strain 43971 biofilms increased at 15 and 25 °C. When the two strains were mixed, the aspect of biofilm formation was similar to that of strain 43971 except that the heat and chemical resistance were higher at 37 °C maturation. Following 9 days of biofilm maturation, we concluded that 15 °C compared with 25 and 37 °C was the optimal condition for rdar and bdar strains in terms of quantity of total cell mass, EPS secretions and resistance against heat and chemical treatments.