Oxoid develops database
identification capabilities of food microbiology laboratories has
been developed.
Designed for use with the MicroStation microbial identification system from Oxoid, the system provides accurate and reproducible identification of over 2000 species of bacteria, yeast and fungi.
The database was developed in collaboration with two world-renownedmycologists, Dr John Bisset at Agriculture and Agri-Food, Canada and Dr Rob Samson at Centraalbureau Voor Schimmelcultures, the Netherlands. It was designed for the identification of sporulating fungal genera important in food spoilage, environmental monitoring and agriculture.
Fungal spoilage is responsible for significant losses in the food industry. Traditional methods for the identification of fungal species are often subjective and time-consuming.
But by simplifying and improving the identification and characterisation of filamentous fungi, the MicroStation system provides accurate and reproducible results significantly faster than traditional methods - in days rather than weeks.
The Filamentous Fungi database also includes a comprehensive library of microscopic and macroscopic digital photographs that can be reviewed automatically, allowing verification of identifications with morphological criteria.
In addition to providing accurate identifications and characterisations, the MicroStation system can be used to trace sources of contamination by comparing the carbon utilisation fingerprints of individual strains of bacteria or fungi with those from environmental samples.
MicroStation's microbial identification technology is based on patented carbon-source utilisation 'fingerprinting'. Following isolation on solid media (and, for bacterial cultures, Gram staining to determine the testing protocol) the organism is introduced to a wide variety of pre-selected carbon sources in the 96-well MicroPlate.
Incubation for four hours or less then produces a characteristic biochemical pattern called a metabolic fingerprint. An accurate identification of the organism is then obtained by comparison with stored fingerprints in the MicroLog databases.
Oxoid claims that the quality of microbial identifications that can be obtained using MicroStation would normally involve the use of labour-intensive strips and panels, and could only be performed in large reference laboratories. The semi-automated MicroStation system has eliminated these time consuming steps, allowing any size of laboratory to perform more rapid identifications and characterisations.
'Fingerprinting' technology is increasingly being applied in food analysis. Scientists from the University of Seville, Spain, for example have developed a method of finger-printing champagne, cava, and other wines to prevent cheaper products being passed off as the more expensive varieties.
A recent article in New Scientist magazine said that tests were 100 per cent accurate in determining which of 35 samples were cava and which were champagne.
Atomic absorption spectrometry was used to measure the concentrations of 16 trace metals in the champagne and cava. The results showed that nine of these could be used to give the wines a unique fingerprint that was different in the case of cava and champagne.
