APPELMANA METHOD — a method of definition of lytic activity of a bacteriophage on fluid mediums by establishment of its maximum cultivation causing a full lysis of bouillon culture of bacteria.
In a row sterile test tubes from neutral glass with an identical diameter pour on 4,5 ml of a medium (usually a beef-extract broth). Bring 0,5 ml of the examinee of a phage which is consistently parted further in the first test tube of a row, transferring from a test tube to a test tube 0,5 ml (every time a separate sterile volume pipette). Usually prepare 10 cultivations of a phage. Excess 0,5 ml pour out of the last (10th) test tube. Then bring 1 — 2 drops of 18-hour bouillon culture in all test tubes. Control is served by additional test tubes — 11 and 12; in one of them there is a liquid medium and culture (without phage), in another — a medium (control of sterility). All test tubes incubate in the thermostat at t ° 37 ° during the 18th hour. The lytic activity of a phage expressed in a caption is established on the last test tube, in a cut there is no turbidity or a deposit. At the accounting of results of experience of a test tube it is necessary to stir up. Thus, the caption of a bacteriophage, across Appelman, is expressed by the maximum cultivation of a phage, at Krom there was a full lysis of the corresponding culture: e.g., the caption of the bacteriophage which gave a lysis in the first 7 test tubes of a row is equal to 10 - 7 .
The data obtained by titration across Appelman characterize only lytic activity of a phage. Concentration of phage corpuscles is defined by titration of a phage on solid nutrient mediums.
See also Bacteriophage .
D. M. Goldfarb.