- 著者
-
鈴木 三郎
- 出版者
- 公益社団法人 日本獣医学会
- 雑誌
- 日本獸醫學會雑誌
- 巻号頁・発行日
- vol.1, no.2, pp.81-84, 1922
The broth used as the basis of various culture-media for bacteria does not contain so much protein as to meet the demand of the pathogenic bacteria for nitrogen and a certain amount of peptone should, therefore, be added to it. MARTIN recommended a process of meat digestion with the addition of pepsin while HOTTINGER used pancreatin for the same purpose; they obtained a broth with so much peptone that no addition of commercial peptone was required, but these methods are somewhat complex and require much time.<br>Recently the author devised a very simple method to prepare a broth rich in peptone, obtaining a good result by the use of papain, a vegetable digestive ferment, for the digestion of meat Papain acts most energetically at 85°C, unlike pepsin and trypsin, and its action is complete in a few minutes, disappearing at a temperature of nearly 100°C. The process is as follows:<br>1. For general use. Mix one pound of horse-flesh or beef with one litre of water; add 1.5gr. of papain and boil the mixture over the fire or in KOCH'S steam sterilizer. As the temperature of the mixture passes 85°C, 70% of the protein of the meat will be transformed into peptone. Filter and wash the residue with water; mix the filtrate and the water used in washing the residue; fill up to 3 litres by adding water; add 30gr. of sodium chloride. In the filtrate thus prepared is contained about 2% of peptone.<br>2. For preparing materials for immunization. The process is similar to that just described above, but the quantity of papain should be reduced to 1/3 and the total amount of the broth up to one litre. In this case the protein digested is as much as 40% and the content of peptone in the broth as mounts to about 5, 4%.