Image Analysis Semi-Automatic System for Colony-Forming-Unit Counting.

BACKGROUND

Accurate quantitative analysis of microorganisms is recognized as an essential tool for gauging safety and quality in microbiology settings in a wide range of fields. The enumeration process of viable microorganisms via traditional culturing techniques are methodically convenient and cost-effective, conferring high applicability worldwide. However, manual counting can be time-consuming, laborious and imprecise. Furthermore, particular cases require an urgent and accurate response for effective processing.

METHODS

To reduce time limitations and discrepancies, this work introduces an image processing method capable of semi-automatically quantifying the number of colony forming units (CFUs). This rapid enumeration technique enables the technician to provide an expeditious assessment of the microbial load of a given sample. To test and validate the system, three bacterial species were cultured, and a labeled database was created, with subsequent image acquisition.

RESULTS

The system demonstrated acceptable classification measures; the mean values of , and were: (1) 95%, 95% and 0.95 for ; (2) 91%, 91% and 0.90 for ; and (3) 84%, 86% and 0.85 for .

CONCLUSIONS

Evidence related to the time-saving potential of the system was achieved; the time spent on quantification tasks of plates with a high number of colonies might be reduced to a half and occasionally to a third.