Biochemical, immunological, and molecular biological tests for microbial identification or the differentiation between groups of organisms are used regularly in microbiological quality control at production facilities and in academic research. Such microbial identification tests detect specific proteins, certain biochemical activities of the target cells (for example the activity of an enzyme), or gene sequences that are characteristic for microorganisms. Many microbial identification tests deliver important results within a short time, are very economical and user-friendly, and most do not need specific equipment or instrumentation. Some biochemical tests require only a drop of reagent to be applied on an agar plate or in a liquid medium.
The advanced microbial identification system HybriScan® is a rapid molecular biology test for the accurate detection and identification of spoilage and pathogenic microorganisms in beverages, water, and food. It is based on in situ hybridization with probes. A robust test in a microtiter plate format, the microbial identification system does not require a thermocycler like a PCR test does.
Biochemical reagents form the basis for liquid biochemical tests to detect, for example, an enzyme activity that is characteristic for a target microorganism. Such tests can often be performed directly on agar plates or liquid media.
Discs, strips, and ID membranes are among the many user-friendly microbial identification test formats based on biochemical reagents and reactions. The reagents are impregnated on a carrier, for example paper, and are therefore stable and easy to handle. A well-known example are the oxidase strips to check for cytochrome oxidase activity.
The test kits are based on different methods, including biochemical and immunological ones. The results can be evaluated by, for example, visible coagulation, a color reaction, or turbidity.
Reagents and kits for staining microorganisms are used to differentiate and identify these under the microscope. Well-known tests like Gram staining help to give further biochemical, structural, or morphological information.
Learn about the advantages, disadvantages, and costs of the HybriScan® method compared to common methods.