title: Effect of nisin on the growth of Staphylococcus aureus determined by a microcalorimetric method.
abstract: A novel microcalorimetric technique based on the bacterial heat output was applied to evaluate the biological effect of nisin on the growth of Staphylococcus aureus. The thermogenic curves of S. aureus in the presence of nisin were studied by an LKB-2277 Thermal Activity Monitor. The thermokinetic parameters, such as the growth rate constant (k), the generation times (G), the inhibitory ratio (I), and the half inhibitory concentration (IC50), for the growth of S. aureus at different nisin concentrations were determined. The relationship between the growth rate constant (k) and the concentration of nisin (c) is nearly linear, which can be modeled by the formula k = 0.03794 - 4.005 x 10(-4) x c, with a correlation coefficient of -0.9971. Based on this model, we obtained the critical inhibitory concentration of nisin on the growth of S. aureus at 94.73 IU/mL. We proposed that this microcalorimetric method could be a useful tool in monitoring the biological effect of nisin on microorganisms, and providing valuable information on the study of microorganism metabolisms.
authors.affiliation: Department of Food Safety and Microbiology, HuaZhong Agricultural University, Wuhan, PR China. wxh@mai.hzau.edu.cn
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Wang
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Bijun
authors.initials: B
authors.lastname: Xie
authors.forename: Xianming
authors.initials: X
authors.lastname: Shi
authors.forename: Junchu
authors.initials: J
authors.lastname: Zhou
authors.forename: Honglin
authors.initials: H
authors.lastname: Zhang
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002151:Calorimetry / Q000379:methods*; D004305:Dose-Response Relationship, Drug; D007700:Kinetics; D009561:Nisin / Q000008:administration & dosage / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development*
chemical_list: D000900:Anti-Bacterial Agents; D009561:Nisin