Dielectric monitoring of growth and sporulation of Bacillus thuringiensis.

UMR Ingénierie de la Réaction Biologique--Bioproductions, Université Montpellier II, 34095, Montpellier, France.
Biotechnology Letters (Impact Factor: 1.74). 05/2005; 27(7):511-7. DOI: 10.1007/s10529-005-2543-x
Source: PubMed

ABSTRACT On-line permittivity and optical density measurements have been used to monitor biomass concentration and sporulation status during growth of a spore-forming bacterium, Bacillus thuringiensis, in fed-batch culture. The correlation between permittivity, optical density and other observations showed three distinct phases of growth: growth itself, transition and sporulation. The permittivity variations during the transition and sporulation phases could be related to the sporulation development: the evolution pattern of the ratio of optical density to permittivity was representative of the culture state, and during the sporulation phase, a permittivity index could be build to measure the extend of spore liberation.

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