Selective Media

Selective media inhibit the growth of organisms other than the one being sought. For example, Thayer-Martin agar is used to isolate Neisseria gonorrhoeae from clinical specimens. This is chocolate agar to which three or more antimicrobial drugs have been added. The antimicrobials inhibit fungi, Gram-positive bacteria, and Gram-negative rods. Because these drugs do not inhibit most strains of N. gonorrhoeae, they allow growth with little competition from other organisms.

Table 4.6 Ingredients in Two Representative Types of Media that Support the Growth of E. coli

Nutrient Broth


(complex medium)

(defined medium)



Meat extract

Dipotassium phosphate


Monopotassium phosphate

You Are What You Eat

You Are What You Eat

Nutrition is a matter that people spend their careers learning about and requires volumes of books to explain. My objective is to instruct you how to consume a healthy nutritional diet that aids your body in burning off fat instead of storing it. You do not require overwhelming science to get this.

Get My Free Ebook

Post a comment