Lactobacillus Research Today is a free monthly online journal that collates and summarizes the latest research about Lactobacillus, including details on probiotics, digestion, diet, health, lactobacillus acidophilus.

Rapid detection and counting of viable beer-spoilage lactic acid bacteria using a monoclonal chemiluminescence enzyme immunoassay and a CCD camera.

March C, Manclús JJ, Abad A, Navarro A, Montoya A

Centro de Investigación e Innovación en Bioingeniería, Universidad Politécnica de Valencia, Camino de Vera, s/n. 46022 Valencia, Spain.

A chemiluminescence enzyme immunoassay carried out with a monoclonal antibody (MAb) and a charge-coupled device (CCD) camera was developed for rapid enumeration of viable beer-spoilage lactic acid bacteria. LA-4 MAb, which recognizes a broad spectrum of lactic acid bacteria isolated from several breweries across Spain, was produced and characterized. Test samples were filtered through polycarbonate membranes, and the membranes with retained bacteria were incubated at 31 degrees C for 2 days. They were then subjected to a two-step chemiluminescence enzyme immunoassay with MAb LA-4, and light-emitting points were detected and counted with a CCD camera. Eighteen out of 19 beer-spoilage lactic acid bacteria analysed produced luminous spots that could be enumerated. Results provided by the immunochemiluminescence assay correlated very well with those obtained by visual plate counting within a range of 3-100 CFU/100 ml. Correlation coefficients were 0.994 for four strains in sterile saline solution and 0.984 for 14 strains in artificially contaminated beer. The excellent agreement suggests that luminous spots detected within 2 days of culture are produced only by viable cells.

Published 22 August 2005 in J Immunol Methods, 303(1): 92-104.
Full-text of this article is available online (may require subscription).

© 2004-2008 Lactobacillus Research Today. All Rights Reserved.