Processing of bacterial colony images for automatic isolation and transfer

A review of the current state of digital plate reading of cultures in clinical microbiology

Digital plate reading (DPR) is increasingly being adopted as a means to facilitate the analysis and improve the quality and efficiency within the clinical microbiology laboratory. This review discusses the role of DPR in the context of total laboratory automation and explores some of the platforms currently available or in development for digital image capturing of microbial growth on media. The review focuses on the advantages and challenges of DPR. Peer-reviewed studies describing the utility and quality of these novel DPR systems are largely lacking, and professional guidelines for DPR implementation and quality management are needed. Further development and more widespread adoption of DPR is anticipated.

Effective object recognition for automated counting of colonies in Petri dishes (automated colony counting)

Determination of the number of colonies (colony forming units, CFU) is a standard method in microbiological analysis to ensure the quality of drinking water. Normally this tedious work is still performed manually. A PC-based method for the automated counting of digitized images of Petri dishes is presented. The method includes highly specific and effective object recognition algorithms that ensure very high detection accuracy. The processing sequence implies internal controls therefore enabling reliable automated evaluations of series of images. Use of the Fuzzy formalism and the high adaptivity of the algorithms lead to an extraordinary user-friendliness. For digitization different devices like flatbed scanners or CCD-cameras can be used. Due to the highly adaptive algorithms samples from the routine standard preparation process in laboratories can be evaluated. The accuracy and quality of the method aim at advancement in objectivity of colony counting and quality control and assurance. The algorithms and the evaluation of the method are presented.

Characterization of bacterial growth on solid medium with image analysis

Alkaliphilic bacterial strains producing the enzyme cyclodextrin glucanotransferase were cultivated on solid agar medium containing an indicator system detecting the enzyme. The growth of the colony and the surrounding diffusion zone, due to the enzyme, were measured by the image analysis during the cultivation. It was possible to differentiate between relatively similar clones by observing quantitatively the changes at and around the colony. Optimal experimental conditions for such measurements are discussed. The image analysis technique provides a potential tool for characterizing microbes grown on solid media.

Vision Assisted Robotics and Tape Technology in the Life-Science Laboratory: Applications to Genome Analysis

Recent proposals to analyze a number of major genomes have created a need for methods of rapidly manipulating and assaying very large numbers of specimens containing DNA fragments. Systems for sampling semi-solid biological material from mixed disordered arrays are required. These samples need to be sorted in an ordered format and stored in minimum space at known locations. It should be possible to recall them quickly from stock, individually or collectively, for duplication or re-ordering into new arrays for appropriate analysis. This article reviews a range of problems associated with high speed multiple specimen handling and assay in the molecular biology laboratory and outlines the solutions currently available to address these difficulties. Designs for automatic systems to manipulate biosamples and analyze DNA are presented.