382 



CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



(3) Strain the separated whey thru a 

 thick, clean cloth. 



(4) Make the reaction of the fluid 

 neutral to litmus by means of an 

 organic acid, such as citric acid. 



(5) Steam 60 minutes. 



(6) Filter while hot thru well-wetted, 

 thick filter paper. 



(7) Add litmus solution to give a deep 

 purple red color. 



(8) Distribute into flasks or test tubes, 

 (c) Klimmer gave the following method 



of preparation. 



(1) Coagulate the casein in milk by 

 the addition of rennet by heating 

 at 40°C. 



(2) Filter. 



(3) Boil the filtrate for 2 hours. 



(4) Neutralize. 



(5) Filter. 



(6) The whey should be water clear 

 and slightly yellow. 



(7) Add 5.0 cc. of sterile litmus solu- 

 tion to each 100.0 cc. of whey. 



(8) Add acid or alkali until the me- 

 dium is a violet color. 



(9) Filter. 



(10) Sterilize (method not given). 

 References: Durham (1900-01 p. 379), 

 Heinemann (1905 p. 128), Abbott (1921 

 p. 140), Harvey (1921-22 p. 95), Klimmer 

 (1923 p. 207). 



1308. Giltner's Sour Whey 



Constituents: 



1. Whey. 

 Preparation : 



(1) Inoculate sweet milk with a pure 

 active culture of Bad. lactis acidi or 

 Bad. bulgaricum as desired and in- 

 cubate at 30°C. 



(2) Allow the maximum acidity to form. 



(3) Cut the curd and heat in flowing 

 steam for 20 to 30 minutes. 



(4) Strain thru cheese cloth and allow to 

 drain. 



(5) Filter thru filter paper. 



(6) If clear whey is desired it is necessary 

 to clear the medium by the addition 

 of egg albumin. 



Sterilization: Not specified. 



Use: To determine the acid destroying 



ability of bacteria. 

 Reference: Giltner (1921 p. 365). 



1309. Bronfenbrenner, Davis and Mori- 



shima's China Blue Rosolic 



Acid Whey Solution 



Constituents: 



1. Water 200.0 cc. 



2. Whey 100.0 cc. 



3. MnCU (10.0% soln.) 2.5 cc. 



4. China blue, rosolic acid 

 indicator 3.0 cc. 



Preparation : 



(1) Allow fresh milk to stand and syphon 

 the milk from under the cream. 



(2) Bring it to boiling and add 2.5 cubic 

 centimeters of 10% MnCU solution to 

 each 100 cubic centimeters of milk. 



(3) Cool the mixture as soon as a clot is 

 formed and filter thru a single layer 

 of cloth. 



(4) Titrate an aliquot portion hot and 

 adjust the bulk of medium to neutral 

 reaction (1 X 10"'). 



(5) Bring quickly to boiling, cool and 

 filter thru paper. 



(6) Dilute the filtrate with double its 

 volume of water and add 1 cubic 

 centimeter of china blue rosolic acid 

 indicator, see medium 535, under 

 variants, for each 100 cubic centi- 

 meters of medium. (At this point, 

 the medium will have an intensely 

 blue color). 



(7) Distribute into sterile tubes con- 

 taining inverted fermentation tubes. 



Sterilization: Autoclave at 15 pounds pres- 

 sure for 10 minutes. Immediately after 

 autoclaving the medium will have a pink 

 color. On cooling it will become colorless 

 if it is properly neutralized. 



Use: Cultivation of colon-typhoid group. 

 Author reported that the medium gave 

 as good results as lactose-peptone water 

 as a medium for colon-typhoid bacteria 

 and was cheaper and more easily 

 prepared. 



Reference: Bronfenbrenner, Davis and 

 Morishima (1918-19 p. 347). 



1310. Jouan's Litmus Whey Solution 



Constituents: 



1. Water 2000.0 or 3000.0 cc. 



2. Whey 1000.0 cc. 



3. CaCli (25.0% soln.) 10.0 cc. 



