Question

This is an microbiology experiment course.

During an enrichment, the culture conditions can be adjusted so growth of unwanted microorganisms is inhibited. Describe two such conditions that would inhibit unwanted microorganisms.

Answer 1

Hi,

The Selective media are used for selecting the organism of requirement and Inhibiting growth of other microbes. One such example is Ox gal. When this is present in the media, it inhibits gram +ve organisms.

Another example is presence of high concentration of sodium citrate. This inhibits enterobacteria such as e coli and Salmonella.

We can also use pH to inhibit microbes. Like pH of above 8 inhibits most enteric bacteria.

Another example I'd temperature. If we want to select organism which grows in high temperature then culturing media at both temperature would inhibit other microbes.