"Microbiology Topics" discusses various topics in microbiology of practical use in validation and com­ pliance. We intend this column to be a useful resource for daily work applications. Reader comments, questions, and suggestions are needed to help us fulfill our objective for this col­ umn. Please send your comments and suggestions to column coordinator Scott Sutton at scott.sutton@ microbiol...

IM A G E S O U R C E , M E D IC A LR F. C O M /G E T T Y IM A G E S “Microbiology Topics” discusses various topics in microbiology of practical use in validation and compliance. We intend this column to be a useful resource for daily work applications. Reader comments, questions, and suggestions are needed to help us fulfill our objective for this column. Please send your comments and suggestio...

1 Clermont Université, Université Blaise Pascal, LMGE, F-63000 Clermont-Ferrand, France 2 CNRS, UMR 6023, Laboratoire Microorganismes: Génome et Environnement, BP 80026, F63171 Aubière Cedex, France Clermont Université, Université Blaise Pascal, ICCF, F-63000 Clermont-Ferrand, France CNRS, UMR 6504, Institut de Chimie de Clermont-Ferrand, BP 80026, F-63171 Aubière Cedex, France * magalie.stauff...

The fungus Polymyxa betae is an obligate parasite of the roots of many plants of the family Chenopodiaceae. In the sugar beet, it acts as a vector of beet necrotic yellow vein virus, the agent of a serious disease known as rhizomania. With indirect methods of analysis, such as bioassay, one can establish only the presence or absence, but not the quantity, of P. betae in soil. A new method based...

Cryptosporidium is globally established as a contaminant of drinking and recreational waters. A previously described cell culture infectivity assay capable of detecting infectious oocysts was adapted to quantify viable oocysts through sporozoite invasion and clustering of foci. Eight experiments were performed by using oocysts less than 4 months of age to inoculate host HCT-8 cell monolayers. O...

The quantification of microorganisms present in food samples is an important step to assess the risk to consumers. The number of salmonellae in 20 positive samples of minced pork was determined by the Most Probable Number method. Counts ranging between <3 and 240 cfu.g were found in the analyzed samples.

AIMS To better understand and manage the fate and transport of Salmonella in agricultural watersheds, we developed a culture-based, five tube-four dilution most probable number (MPN) method for enumerating dilute densities of Salmonella in environmental waters. METHODS AND RESULTS The MPN method was a combination of a filtration technique for large sample volumes of environmental water, stand...

The validity of survivor curves for Leptospira autumnalis Akiyami A based on most-probable-number values is supported by the following observations: (i) linear regression lines fell within most of the 95% confidence intervals; (ii) linear correlation coefficients (r) were consistently high (i.e., near -1); and (iii) statistical tests for goodness of fit usually accepted the linear model. These ...