CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



735 



(6) Tube. 



(7) Sterilize in the Arnold 20 to 30 min- 

 utes on 3 successive days. 



References: Schultz (1891 p. 62), Acosta 

 and Grande (1892 f^U), Frothingham 

 (1895 p. 55), Forster (1897 p. 342), Jensen 

 (1898 p. 406), Committee A. P. H. A. (1899 

 p. 77), Migula (1901 p. 13), Thoinot and 

 Masselin (1902 pp. 30, 32), Frost (1903 

 p. 6), Abel (1912 p. 15, 17), Lohnis (1913 

 p. 14), Meier (1918 p. 435), Worth (1919 

 p. 608), Besson (1920 p. 39), Abbott 

 (1921 p. 125), Dopter and Sacquepee 

 (1921 p. 124), Harvey (1921-22 p. 70), 

 Pitfield (1922 p. 116), Klimmer (1923 

 p. 192), Park, Williams and Krumwiede 

 (1924 p. 117). 



2280a. Koch's Nutrient Gelatin 



Constituents : 



1. Any nutrient medium, 



double strength 1000.0 cc. 



2. Gelatin solution, 5 to 6%. . . 1000.0 cc. 

 Preparation : 



(1) Place gelatin in distilled water and 

 dissolve by warming. A concentra- 

 tion of 5 to 6% gelatin recommended. 



(2) Add this gelatin solution to an equal 

 volume of any nutrient medium 

 (double strength). 



(3) Neutralize with sodium or potassium 

 hydroxide or phosphate. 



(4) Boil and filter off precipitate. 



(5) Place in sterilized cotton stoppered 



Sterilization: Sterilize by boiling. 



Use : General culture medium and isolation 



of cholera bacillus. 

 Variants : 



(a) The author stated that larger quanti- 

 ties of gelatin might be used, that 

 the gelatin may be dissolved directly 

 in the nutrient medium. 



(b) Hueppe (1885) prepared the medium 

 as follows: 



(1) Add 5 or 10% finely cut gelatin to 

 any desired nutrient medium. 



(2) Allow to soak for half an hour. 



(3) Heat to dissolve. 



(4) Neutralize by the addition of so- 

 dium carbonate, or make slightly 

 alkaline to litmus. 



(5) Heat on the water bath for an hour 

 and filter thru a damp filter paper. 



References: Koch (1881 p. 169), Hueppe 

 (1885 p. 101-104), Koch (1887 p. 161). 



2281. Smith's Peptone Infusion Gelatin 



Constituents : 



1. Distilled water 1000.0 cc. 



2. Lean beef 500.0 g. 



3. Peptone (Witte) 10.0 g. 



4. Gelatin (best white French) 10.0 g. 

 Preparation : 



(1) Prepare a medium from the constit- 

 uents, method not given. 



(2) Add enough KOH to neutralize to 

 litmus. 



Sterilization: Sterilize (method not given). 

 After sterilization reaction slightly acid 

 to litmus. 



Use: Smith used the medium for the culti- 

 vation of Pseudomonas campestris Pam- 

 mel. He reported that the gelatin was 

 slowly but distinctly liquefied. Slight 

 growth on this medium. The presence of 

 salt hindered the growth. Would not 

 grow on a medium alkaline to phenol- 

 phthalein. Similar media were used as 

 general culture media and also in water 

 analysis. 



Variants : 



(a) Committee A. P. H. A. (1901) recom- 

 mended the following method of 

 preparation: 



(1) Infuse 500.0 g. lean meat 24 hours 

 with 1000.0 cc. of distilled water in 

 refrigerator. 



(2) Make up loss by evaporation. 



(3) Strain infusion thru cotton flannel. 



(4) Weigh filtered infusion. 



(5) Add 1.0% Witte's peptone and 

 10.0% gold label sheet gelatin. 



(6) Warm on water bath, stirring till 

 peptone and gelatin are dissolved 

 and not allowing the temperature 

 to rise above 60°C. 



(7) Heat over boiling water (or steam) 

 bath for 30 minutes. 



(8) Restore loss by evaporation. 



(9) Titrate after boiling one minute 

 to expel carbonic acid. 



(10) Adjust reaction to -1.0% by add- 

 ing normal hydrochloric acid or 

 sodium hydrate as required. 



(11) Boil 2 to 5 minutes over a free 

 flame constantly stirring. 



(12) Make up loss by evaporation. 



