ABSTRACT
AIMS: The main objective of our study was to assess the persistence of Mycobacterium avium in an oligotrophic environment such as bottled groundwater. METHODS AND RESULTS: Filtered groundwater samples were spiked with washed Myco. avium suspension and stored in dark and under static conditions, at 20 degrees C, for 3 months in 500 ml PET bottles. The loss of Myco. avium cultivability was slow in water. On the contrary, after a 3-month storage at 20 degrees C, growth of attached cells was observed and cell adhesiveness to the PET wall increased with time. It could probably be because of the presence of an extracellular matrix. CONCLUSIONS: This study has shown the great stability of Myco. avium in bulk water as well as their adhesiveness and their growth on a PET bottle wall in an oligotrophic environment. SIGNIFICANCE AND IMPACT OF THE STUDY: Slowly growing mycobacteria are well adapted to oligotrophic environments such as groundwater. As they stick very well to surfaces, they could be used for determining the efficiency of the cleaning of contaminated surfaces.
Subject(s)
Bacterial Adhesion , Mineral Waters/microbiology , Mycobacterium avium/growth & development , Polyethylene Terephthalates , Water Microbiology , Colony Count, Microbial , Microscopy, Fluorescence , Product Packaging , Time FactorsABSTRACT
AIMS: The main objective of the present study was to estimate the survival of microaerophilic Campylobacter jejuni in filtered natural mineral water at 4 degrees C and 25 degrees C. The influence of the presence of biodegradable organic matter was tested, assuming that the bacterial contamination of a bottled natural mineral water could be associated with contamination by organic matter. METHODS AND RESULTS: Washed Campylobacter cultures were inoculated in natural mineral water and sterile natural mineral water, and incubated in the dark at 4 degrees C and 25 degrees C. The effect of temperature, the biodegradable organic matter added, incubation atmosphere and autochthonous microflora were tested on the cultivability of Camp. jejuni. CONCLUSIONS: The survival of Camp. jejuni in natural mineral water was better at 4 degrees C than at 25 degrees C, and the presence of organic matter led to a deceleration in the loss of cultivability and to the multiplication of Camp. jejuni in natural mineral water. SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlighted the fact that, in the event of dual contamination of a bottled natural mineral water (Campylobacter and biodegradable organic matter), the pathogen could survive (and even grow) for a relatively long time, especially at low temperature and in spite of the presence of oxygen.
