Question

What is the difference between primary and secondary screening of microorganisms and a couple of examples of techniques utilized to do each?

Answer 1

Primary screening helps in isolation and detection of microorganisms whereas secondary screening helps in determining of yield or production of microorganisms. These are usually employed for screening of microbes for their ability to produce antibiotics. This is the basic difference between primary and secondary screening.

Techniques used in Primary Screening:

i) Crowded Plate technique - used for those microbes which produces antibiotics

ii) Indicator dye technique - for acid and amine producing microorganisms

Techniques used in Secondary screening:

i) Giant colony technique

ii) Liquid medium method