Selective Media - Lab Report Example

Selective media has a limited number of microorganisms it can support in growth because the particular component inhibits most other microorganisms by either limiting their growth or production of toxic substance that inhibit growth of non-selected microbes hence appropriate in the selection of target microorganisms during diagnosis. Diagnostic procedures utilising growth characteristics of enteric microorganisms is one of the cheapest and the easiest microbiological protocol that can be adopted in any low-income laboratory or a facility with high throughput diagnostic equipments.

During the diagnosis of enteric medical conditions, use of growth media in the diagnosis of microorganisms gives reliable information that guides subsequent diagnostic studies that aims at targeting a particular pathogen. However, the growth of microorganisms is a characteristic of the media used in the assessment of growth. All media do not support the growth of all pathogens. In fact, only nutrient agar can support the growth of most microorganisms. Therefore, utilising a particular media that targets an individual pathogen is a crucial phenomenon in bacterial culture laboratory practices.

Media are made selective for a particular microorganism by the incorporation of growth enhancement component that targets a particular pathogen as well as growth limiting component that inhibits the growth of unwanted organisms. Such media is referred to as selective media because it either enhances or inhibits the growth. Using selecting media makes it easy to discriminate most unwanted pathogens that arise from environmental contamination and likely to give false positive diagnosis. This report assessed the growth, morphology characteristics, differential colony features of the four selected microorganisms (E.

coli, Salmonella tyhimum, Shigella flecked, and Staphylococcus spp) on five selected selective media (Phenylethyl alcohol – PEA; Hektoen enteric agar- HEK;