Martinus beijerinck developed the enrichment culture technique to isolate metabolically-distinct microbes from complex natural samples, like soil and water, by manipulating the

By manipulating the culture conditions and nutrients.

Enrichment culture refers to the application of some kind of growth media to favor the development of a specific microorganism over the others, elevating a sample for the microorganism, which is of interest. This is usually attained by administrating nutrients or favorable environmental conditions, which permit the development of the desired organism.