Traditional separation and purification of microorganisms

What are the effects of selective culture methods and techniques for separating and purifying microorganisms on the experimental results?

Factors affecting the isolation of pure microbial strains;

1. Other bacterial invasion;

2. Changes in the growth process;

3. The temperature and humidity should be appropriate.

Introduction:

Isolation of pure strains of microorganisms: a seed selection method, which attempts to select a certain cell to reach the level of "colony line" or "strain line" by some methods.

Separation method of pure microbial strains;

(1) dilution plate separation

Gradually dilute the sample to be tested to a certain concentration gradient according to a certain method, select the sample with suitable dilution concentration, and inoculate and cultivate for a certain time to obtain microbial colonies.

(2) separation of plate scribing

Select an appropriate amount of samples (mixed samples of microorganisms) with inoculation tools, draw lines on the culture medium plate according to a certain method, and after a certain period of culture, microbial colonies can be obtained, and then pure cultures of microorganisms can be obtained.

(3) selective culture and separation

According to the unique physiological characteristics of cultured microorganisms, selective culture medium with strong pertinence is used for culture.