Publications by authors named "H Girardin"

The survival and transfer of Listeria innocua and Clostridium sporogenes, used as surrogates of the food borne pathogens Listeria monocytogenes and Clostridium botulinum, were quantitatively assessed under field conditions. In the soil, spores of C. sporogenes declined by less than 0.

View Article and Find Full Text PDF

A food processing plant producing pasteurized purées and its zucchini purée processing line were examined for contamination with aerobic and facultative anaerobic bacterial spores during a day's operation. Multiplication of spores was also monitored in the product stored under different conditions. High concentrations of Bacillus cereus spores were found in the soil in which the zucchinis were grown (4.

View Article and Find Full Text PDF

Research interest in microbial biodiversity over the past 25 years has increased markedly as microbiologists have become interested in the significance of biodiversity for ecological processes and as the industrial, medical, and agricultural applications of this diversity have evolved. One major challenge for studies of microbial habitats is how to account for the diversity of extremely large and heterogeneous populations with samples that represent only a very small fraction of these populations. This review presents an analysis of the way in which the field of microbial biodiversity has exploited sampling, experimental design, and the process of hypothesis testing to meet this challenge.

View Article and Find Full Text PDF

The saprophytic Paenibacillus and Bacillus spp. found in cooked chilled foods may have an effect on the growth of Clostridium botulinum, a major microbiological hazard, especially for pasteurized vacuum-packaged products. Culture supernatants of 200 strains of Paenibacillus and Bacillus strains isolated from commercial cooked chilled foods containing vegetables were screened for activity against C.

View Article and Find Full Text PDF

When cultivated in the presence of trypsin, the Ruminococcus gnavus E1 strain, isolated from a human fecal sample, was able to produce an antibacterial substance that accumulated in the supernatant. This substance, called ruminococcin A, was purified to homogeneity by reverse-phase chromatography. It was shown to be a 2,675-Da bacteriocin harboring a lanthionine structure.

View Article and Find Full Text PDF