From Big Medical Encyclopedia

TINDALLIZATION — a method of destruction of spore-formers in various objects by fractional influence by heat.

It is offered in 1877 by the English scientist J. Tyndall for sterilization of thermolabile substances.

T. subject the objects which are not maintaining temperature higher than 100 °. At the same time they repeatedly with breaks are heated: at t 60 — 65 ° heating is carried out on 60 min. daily within 5 days, at t ° 70 — 80 ° — 60 min. within 3 days, at t 100 ° — 30 min. 3 — 4 days. In a break between heating an object is maintained during 24 hours at a temperature of cultivation of vegetative forms of microbes (25 — 37 °).

The essence of a method is that during the heating in the specified modes death of vegetative forms of microorganisms is reached; the subsequent keeping of objects at favorable for germination to temperature (25 — 37 °) leads a dispute to transformation remained a dispute in vegetative forms, to-rye perish at the subsequent repeated action of heat. Antimicrobic effect of T. it is reached only under a condition if Wednesday, in a cut there are microorganisms, and temperature maintained between the periods of heating provide germination a dispute in vegetative forms. This method is not suitable for sterilization of the liquids which are not nutritious substrate for microorganisms. The T is not effective. and when the optimum temperature of cultivation of the microorganisms planting objects is higher 25 — 37 °, napr, for spore-forming thermophilic bacteria, the optimum of temperature of cultivation to-rykh is equal 50 — 56 °, and also concerning spore-forming microbes if germination a dispute happens in anaerobic conditions.

T. use in microbiology prp preparation of the mediums containing complete protein or carbohydrates (Wednesdays on whey, bilious broth, the environment Rapoport, Giss's circles, Russell's circle, Wednesday with urea and carbohydrates, the egg environment of Dorset, sugar broth, etc.).

T. carry out in various devices: steam sterilizers fluid steam (see. Sterilization ), in Koch's device (see. Sterilizers ), on the water bath.

Lack of T. its smaller reliability in comparison with sterilization (see), duration of process, a possibility of increase in initial quantity of microorganisms in an object is during keeping at a temperature of cultivation.

Efficiency of T. control bacterial. by method with use of the test microorganisms having a certain heat stability. For control of temperature and time of T. use potentiometers with thermocouples, the maximum thermometers, hours, etc.

See also Pasteurization .

Bibliography: Vashkov V. I. The means and methods of sterilization applied in medicine, M., 1973; The Guide to clinical laboratory methods of a research, under the editorship of L. G. Smirnova and E. A. Kost, M., 1964; TvndaJl J. Essays on the floating-matter of the air in relation to putrefaction and infection, L., 1881.

H. V. Ramkova.