Validation of the Micro Biological Survey Method for Total Viable Count and E. coli in Food Samples

""The rom of this study was the validation of the Micro Biological Survey (MBS) method for. microbiological analysis of food for Total Viable Count (TVC) and Escherichia coli (E. coli), The. MBS method is a rapid quantitative alternative method for the detection and selective counting of. bacteria in agro-food, in water and in environmental samples. It is based on colorimetric survey in. mono-uss disposable reaction vials that must be filled with the samples without any preliminary. treatment (e.g., homogenization, dilution, etc.); the greater the number ofbacteria presents into. the sample, the faster the color change. However, an independent evaluation of the analytical. results obt.ained with MBS method would be required before commercialization. Therefore, this. alternative method was validated in comparison to the reference method. The general estimate of. precision, reliability, uncertainty, linearity, accuracy and selectivity were determined. Ali the. performance parameters have demonstrated total corrslation between the alternative method and. the reference method for the detection and counting of TVC and E. coli both in artificially. contaminated and in naturaliy contaminated samples. MBS assay can be used as rapid and user. friendly screening method for detection of TVC and E. coli in food industry."

A New Method For Microbiological Analysis That Could Be Used For Point-Of-Care Testing (POCT)

""Abstract: Standardized microbiological methods used in clinical analysis are based on traditional microbial enrichment. on selective media, possibly followed by characterization of bacteria with molecular methods. These techniques present. several difficulties, such as the subjectivity in the interpretation of genetic, biochemical or morphological tests and the. possible interference of biological matrices, specially when low levels of contamination are present. In addition, standardized. microbiological analyses are characterised by the high cost of the method, both in terms of labor and supplies, and. above all, by the long time needed to obtain definitive results (from 3 to 7 days). These reasons have led to the development. and refinement of microbiological POCTs which are now available for several microorganisms, even thought no microbiological. POCT was up to now developed for the count of total viable bacteria (TVC) in serum, urine or other biological. fluids.. MBS srl (a spin-off of Roma Tre University, Rome, Italy) has developed and patented an alternative method for selective. counting of bacteria, called Micro Biological Survey (MBS) method. The MBS method is based on colorimetric survey. performed in mono-use disposable reaction vials in which samples can be inoculated without any preliminary treatment.. The analyses can be carried out by untrained personnel and anywhere they are necessary, without the need for any other. instrumentation than a thermostated optical reader that can automatically detect the colour change providing the number. of bacteria present into the sample. The MBS method measures the catalytic activity of redox enzymes in the main metabolic. pathways of bacteria, allowing an unequivocal correlation between the observed enzymatic activity and the number. of viable cells present in the samples. The time required for a color change is inversely related to the log of bacterial concentration;. like an enzymatic reaction, the greater the number of bacteria, the faster the color change.. The objective of this study was the primary validation, in accord with ISO 13843:2003 (Guidance on validation of microbiological. methods), of the quantitative Micro Biological Survey (MBS) method for Total Viable Count (TVC). Validation. aims to compare the results obtained with an alternative method, in this case the MBS method, with the results obtained. with the reference method. To verify the equivalence between the two methods different parameters were analyzed:. selectivity, linearity and accuracy. The validation has shown that the MBS method gives similar results and is in agreement. with the reference methods. The MBS method could therefore represent a worthy aid in microbiological analysis as. POCT device without replacing the analysis carried out with traditional methods which are very precise though often long. and complex."

A new device for the prompt diagnosis of urinary tract infections

BACKGROUND: Urinary tract infections (UTIs) are among the most common infectious diseases. RESULTS obtained from conventional microbiological analysis of urine and antibiotic susceptibility testing are available only after a few days, delaying precise diagnosis and appropriate therapy. Micro Biological Survey (MBS) srl (a spin-off of Roma Tre University, Rome, Italy) has developed and patented an automated colorimetric test for rapid bacterial counting. In a preliminary validation study it was demonstrated that the results obtained with the MBS method are equivalent to the results obtained with conventional culture-based microbiological analysis. METHODS: In this study, sterile urine samples were artificially contaminated with bacterial species that are most frequently responsible for UTIs. The MBS method was used to evaluate the presence of bacteria and their sensitivity to some of the most commonly used antibiotics in UTIs. RESULTS: The MBS method was able to detect in a few hours the presence or absence of bacteria at clinically significant concentrations (>105 CFU/mL), and to provide their susceptibility pattern to a limited panel of antibiotics. DISCUSSION: The results obtained demonstrate that the MBS point-of-care testing (POCT) device could be developed into a valuable aid for the management of UTIs, possibly addressing more precise diagnosis and appropriate therapy

Qualitative and Quantitative Validation of the Micro Biological Survey Method for Listeria spp., Salmonella spp., Enterobactericeae and Staphylococcus aureus in Food Samples

""The objective of the present study was the preliminary validation in accord with ISO 16140 (2003) of the qualitative MBS methods for Salmonella spp. and Listeria spp. and the quantitative MBS methods for Enterobacteriaceae and Staphylococcus aureus. The MBS method is a rapid alternative method for the detection and selective counting of bacteria in agro-food, in water and in environmental samples. It is based on colorimetric survey in mono-use disposable reaction vials that must be filled with the samples without any preliminary treatment (eg. homogenization, dilution, etc.); the greater the number of bacteria present in the sample, the faster the color change. For the qualitative validation of the MBS methods for Salmonella spp. and Listeria spp., selectivity, relative accuracy, relative specificity and relative sensitive were determined. Selectivity, linearity and accuracy were analyzed for the quantitative validation of the MBS methods for Enterobacteriaceae and Staphylococcus aureus. The validation here reported has shown that the MBS methods for Listeria spp., Salmonella spp., Enterobacteriaceae and S. aureus gave similar results and were in agreement with the reference methods."