Pure Culture

pure culture

In microbiology, laboratory culture containing a single species of organism. A pure culture is usually derived from a mixed culture (containing many species) by methods that separate the individual cells so that, when they multiply, each will form an individually distinct colony, which may then be used to establish new cultures with the assurance that only one type of organism will be present. Pure cultures may be more easily isolated if the growth medium of the original mixed culture favours the growth of one organism to the exclusion of others.

---

pure culture [′pyu̇r ¦kəl·chər]

(microbiology)

A culture that contains cells of one kind, all progeny of a single cell.

---

Pure Culture 

a culture containing cells of a single species of microorganism.

The most reliable way of isolating a pure culture is from a single cell of a population. For yeast and microscopic fungi, this is accomplished by Lindner’s drop technique. Drops from a cellular suspension of yeast or fungi spores (conidia) are transferred to a cover glass, or cover slip. The cover glass is then placed over a cavity slide. Microscopic techniques are used to find a drop containing a single cell, and the drop is then transferred, using sterile procedures, to a culture medium. Pure, single-cell bacterial cultures are isolated with the aid of a micromanipulator or thin capillaries (B. V. Perfil’ev’s microselector).

The isolation of pure cultures is necessary in the classification and study of the variability of microorganisms and in the production of vaccines. It is also used in the microbiological industry for the preparation of enzymes, antibiotics, vitamins, steroid hormones, and other preparations.