730 



CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



(9) Remove from the autoclave, and 

 loosen the solidified gelatin from 

 the walls of the container. 



(10) Upset the gelatin on a filter paper. 



(11) Cut off the turbid upper layer of 

 the gelatin cylinder with a thread 

 or wire. 



(12) Cut the clear gelatin into pieces, 

 place into a flask and melt. 



(13) Distribute into test tubes. 



(14) Sterilize by the discontinuous 

 method, (details not given). 



(b) Frothingham (1895). 



(1) Add one pound of finely chopped 

 lean meat to 1000.0 cc. water and 

 allow to stand from 12 to 24 hours 

 in a cool place. 



(2) Strain thru a cheese cloth or coarse 

 towel and squeeze in a meat press 

 or by twisting the ends of the 

 cloth until 1000.0 cc. of the meat 

 juice is obtained. Make up to 

 1000.0 cc. by the addition of water 

 if necessary. 



(3) Dissolve 5.0 g. NaCl and 10.0 g. 

 dried peptone in (2). 



(4) Add 100.0 g. gelatin to (3). 



(5) Heat in a water bath to 50° until 

 the gelatin is dissolved. 



(6) Make slightly alkaline. 



(7) Boil for 45 minutes to 60 minutes. 



(8) Filter. 



(c) Forster (1897). 



(1) Prepare Loeffler's bouillon. 



(2) Sterilize (1) method not given. 



(3) Heat to 60°C. and dissolve the 

 necessary or required amount 

 (exact amount not given) of 

 gelatin in (1). 



(4) Make slightly alkaline and cool 

 a little. 



(5) Add the white of an egg. 



(6) Place the kettle containing (5) in 

 boiling water, and stir with a 

 spoon to insure equal heating. 



(7) Adjust the reaction once more and 

 heat to 100°C. for 15 minutes. 

 Leave the lid loosely on the kettle. 



(8) Heat a water funnel to 60°C. (not 

 higher) and filter quickly. 



(9) Distribute the filtrate into sterile 

 culture tubes. 



(10) Heat in boiling water or in flow- 

 ing steam at 100°C. for 17 to 20 

 minutes. 



(d) Jensen (1898) cultivated denitrifying 



bacteria on the following medium: 



(1) Prepare an infusion from 500.0 g. 

 meat and 1000.0 cc. of water. 



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

 tone and 200.0 g. of gelatin in (1). 



(3) Adjust the reaction to a slight 

 alkalinity by adding soda. 



(4) Method of sterilization not speci- 

 fied. 



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



(1) Macerate one part finely chopped 

 lean meat with 2 parts distilled 

 water in an ice box for 18 to 24 

 hours, stirring constantly. 



(2) Strain while 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 5 minutes over a 

 free flame. 



(6) Filter while hot thru paper or 

 cotton and cloth, and dissolve 

 10.0% gelatin in the filtrate. 



(7) Add normal HCl to the filtrate to 

 obtain the desired reaction. If 

 the medium is clear distribute in 

 tubes or flasks. If not clear, 

 clarify by adding the whites of 

 one egg to the medium cooled to 

 50 or 60° and boil vigorously. 

 Filter. 



(8) Sterilize either by the fractional or 

 continuous method. 



(f) Migula (1901). 



(1) Mix 500.0 g. of finely chopped lean 

 beef with one liter of water, and 

 allow to stand in the ice box for 

 12 to 24 hours. 



(2) Press the liquid thru a towel and 

 make up the volume to one liter. 



(3) Boil in the steamer cooker for 

 30 minutes. 



(4) The infusion may be boiled for an 

 hour before removing the meat 

 and then filtered thru paper. If 

 the liquid is still red, boil again 

 for 15 minutes. 



(5) Filter when cold to remove any fat. 



(6) Heat to boiling and add 0.5% 

 NaCl, 1.0% Witte's peptone and 



