Journal of Thermal Analysis and Calorimetry

, Volume 108, Issue 2, pp 665–670

Microcalorimetric study of the growth of Enterococcus faecalis in an enriched culture medium

  • Natividad Lago Rivero
  • José L. Legido Soto
  • Lidia M. Casás
  • Isaac Arias Santos
Article

DOI: 10.1007/s10973-011-2052-1

Cite this article as:
Rivero, N.L., Legido Soto, J.L., Casás, L.M. et al. J Therm Anal Calorim (2012) 108: 665. doi:10.1007/s10973-011-2052-1

Abstract

Enterococcus faecalis is a Gram-positive bacteria, considered one of the most common causes of nosocomial infections. Bacterial cultures produce an exchange of energy as a result of the bacteria metabolisms. The rate of heat production is an adequate measure of the metabolic activity of the organisms and their constituent parts. Microorganisms produce small amounts of heat: 1–3 pW per cell. Although the heat produced by bacteria is very small, their exponential reproduction in a culture medium permits heat detection through microcalorimetry. In this study, we analyzed the microcalorimetric behavior of Enterococcus faecalis. A thermal Calvet microcalorimeter was used. The inside of the calorimeter contains two stainless steel cells (experimental and reference). Experiments were carried out at final concentrations of 106,105,103, and 10 CFU/mL and a constant temperature of 309.65 K was maintained within the microcalorimeter. Recording the difference in calorific potential over time we obtained E. faecalis’s growth curves. Thermograms were analyzed mathematically allowing us to calculate the constant growth, generation time and the amount of heat exchanged over the culture time.

Keywords

Enterococcus faecalis Microcalorimetry Metabolism Bacteria 

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2011

Authors and Affiliations

  • Natividad Lago Rivero
    • 1
  • José L. Legido Soto
    • 2
  • Lidia M. Casás
    • 2
  • Isaac Arias Santos
    • 1
  1. 1.Servicio de FarmaciaComplejo Hospitalario Universitario de Vigo (Xeral-Cíes)VigoSpain
  2. 2.Departamento de Física Aplicada, Facultade de Ciencias ExperimentaisUniversidade de VigoVigoSpain