Synbiosis, a world-leading manufacturer of automated microbiological systems, is delighted to announce its ProtoCOL 3 rapid automated colony counter has been shown in an independent study to perform with the same level of accuracy as manual colony counting for enumerating 10 different types of microbial colonies on a range of agar plates.
The study, which was performed to GLP-compliant standards at Don Whitley Scientific Contract Microbiology Laboratory, compared the ProtoCOL 3 system with manual counting for enumeration of bacterial, yeast and fungal colonies on either Plate Count Agar, Columbia Blood Agar or Sabouraud Dextrose Agar plates. These plates were surface spread or spiral plated with one of the following organisms: Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Kocuria rhizophila, Enterococcus faecalis, Mannheimia haemolytica, Bacillus subtilis, Streptococcus pneumoniae, Candida albicans and Aspergillus brasiliensis. The resulting colonies were then enumerated both manually and using the ProtoCOL 3’s powerful software to produce a count.
For each plate type (spiral and spread) the comparison between ProtoCOL 3 and manual counts were analysed statistically using a t-test. The results (p = 0.105 for spiral plate data and p = 0.143 for spread plate data) did not identify significant differences between manual and the automated counting methods, for either plate type, at the 95% confidence level.
Martin Smith at Synbiosis commented: “The microorganisms in this independent study produce colonies of differing colours, shapes and sizes and were also cultured on both translucent and opaque agars, which means some are a real challenge to count automatically. We’re delighted with the results of this study because they show that there is no significant difference between the accuracy of manual and automated counting with the ProtoCOL 3 in what are realistic evaluation situations you’d see in many microbiology laboratories.”
Martin continued: “Being able to accurately enumerate so many types of colonies on different agars is a task very few automated colony counters can perform well and this study validates the ProtoCOL 3’s versatility for this application. Microbiologists looking to increase their throughput of plate counts can now install a ProtoCOL 3, confident that they will automatically count many different types of bacteria, fungi and yeast in a fraction of the time, while still guaranteeing the accuracy they demand from a manual count.”