According to Synbiosis, its rapid automated colony counter works as accurately as manual colony counting.
During the study performed to GLP-compliant standards at Don Whitley Scientific Contract Microbiology Laboratory, the ProtoCOL 3 system was compared with manual counting for enumeration of bacterial, yeast and fungal colonies on either Plate Count Agar, Columbia Blood Agar or Sabouraud Dextrose Agar plates.
The 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, Treptococcus pneumoniae, Candida albicans and Aspergillus brasiliensis.
The resulting colonies were then enumerated both manually and using the ProtoCOL 3’s 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: “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.”
