490 



CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



(10) Neutralize (indicator not speci- 

 fied). 



(11) Filter. 



(12) Sterilization not specified. 



(f) Jensen (1898) studied denitrification 

 using the following medium: 



(1) Prepare a meat infusion from 

 500.0 g. of meat and 1000.0 cc. 

 of water. 



(2) Dissolve 5.0 g. NaCl, 10.0 g. 

 peptone and 15.0 g. agar in (1). 



(3) Adjust to a slight alkalinity with 

 soda. 



(4) Method of sterilization not given, 

 (g) Committee A. P. H. A. (1899). 



(1) Macerate one part finely chopped 

 lean meat with 2 parts distilled 

 water in the ice box for 18 to 

 24 hours, stirring occasionally. 



(2) Strain cold thru a fine cloth. 



(3) Add 1.0% peptone and 0.5% NaCl 

 to the filtrate. Heat until solu- 

 tion is complete. 



(4) Add NaOH until the reaction is 

 slightly alkaline (practically neu- 

 tral) to phenolphthalein. 



(5) Heat on a water bath for 30 min- 

 utes and boil for 5 minutes over a 

 free flame. 



(6) Filter while hot thru paper or cot- 

 ton and cloth, and add 1.0 to 

 2.0% agar to filtrate. Dissolve 

 by boiling or autoclaving. 



(7) Add N/1 HCl to the filtrate to ob- 

 tain the desired reaction (+1.5). 



(8) U the medium is clear distribute 

 in tubes or flasks. If not clear, 

 clarify by adding the white of 

 one egg to the agar cooled to 50 

 to 60°C., and then boil vigor- 

 ously. Filter. 



(9) Sterilize either by the fractional 

 or continuous method. 



(h) Ravenel (1899). 



(1) Mi.x 500.0 g. of freshly chopped 

 meat with 500.0 cc. of water. 



(2) Allow to stand in a cool place 

 over night. 



(3) Strain thru a towel. 



(4) Chop agar into small pieces and 

 add to 500.0 cc. water. 



(5) Put in an autoclave and run the 

 pressure up to two atmospheres 

 (135.1°). Turn out the flame. 



(6) Cool the autoclave at 100°C. be- 

 fore opening. 



(7) Cool to 75°C. 



(8) Mix (7) and (3). 



(9) Add 10.0 g. peptone and 5.0 g. 

 NaCl to (8). 



(10) Boil for 3 to 5 minutes. 



(11) Neutralize (indicator not speci- 

 fied). 



(12) Filter. 



(13) Sterilization not specified. 



(i) Thalmann (1900) used the following 

 medium for the isolation of gono- 

 cocci: 



(1) Cut lean beef into small pieces in 

 , a meat cutting machine. 



(2) Add a double weight of distilled 

 water to (1). 



(3) Boil for 15 minutes stirring con- 

 tinually with a glass rod. 



(4) Make up the loss of water and 

 filter thru a filtering cloth. 



(5) Add 1.0% peptone (siccum) and 

 0.5% NaCl. 



(6) Boil. 



(7) Make up the volume of water 

 lost. 



(8) Cool (in a closed container) and 

 filter. 



(9) Distribute in 300 to 500.0 cc. por- 

 tions in clean flasks with pat- 

 ented sealers. 



(10) Sterilize in streaming steam for 

 one hour. 



(11) Add 1.5% agar to (10). 



(12) Bring to a boil on a concentrated 

 salt solution bath and boil for 

 45 minutes shaking often. 



(13) Take 30.0 cc. of (12) add a drop 

 of alcoholic phenolphthalein solu- 

 tion and add N/1 sodium solution 

 until a red coloration is formed. 



(14) Estimate the amount (12) and 

 calculating from (13) add f the 

 amount of sodium solution re- 

 quired to give neutralization. 



(15) Keep in the autoclave or hot 

 water for 15 minutes. 



(16) Filter. 



(17) Tube. 



(18) Sterilize (exact method not spec- 

 ified). 



(j) Walbaum (1901). 



(1) Method of preparation of meat 

 infusion not given. 



