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CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



3. Potato 100.0 g. 



4. NaCl (0.65) 150.0 cc. 



5. Agar 5.0 g. 



6. Blood, defibrinated horse 

 Preparation : 



(1) Peel 100.0 g. potatoes, cut in small 

 pieces and wash in running water for 

 2 hours. 



(2) Add (1) to 200.0 cc. of distilled water 

 containing 4.0% double distilled acid 

 free glycerol. 



(3) Autoclave for 40 minutes. 



(4) Allow to stand over night and strain 

 thru cheese cloth. 



(5) Mix 50.0 cc. (4), 150.0 cc. of a 0.65% 

 NaCl solution and 5.0 g. agar. 



(6) Steam in the Arnold sterilizer until 

 the agar is dissolved (30 to 60 

 minutes). 



(7) Tube, do not filter. 



(8) When ready for use, melt sterile 

 tubes of (7), cool to about 45°C. and 

 add the desired amount of sterile 

 defibrinated horse blood. 



Sterilization: Method of sterilization of 

 agar not given. 



Use: To maintain stock cultures of menin- 

 gococci. Author reported that trans- 

 plants must be made every two weeks. 

 Incubate at 37.5°C. If tubes are par- 

 affined fair growth after 6 weeks. Gono- 

 cocci grow on this medium when blood 

 content high and salt content dimin- 

 ished. Other authors cultivated the 

 whooping cough bacillus, influenza bacil- 

 lus, etc., on similar media. 



Variants : 



(a) Bordet and Gengou prepared the 

 medium as indicated above. They 

 distributed the agar in 2.0 or 3.0 cc. 

 lots and added an equal volume of 

 sterile defibrinated rabbit or human 

 blood to the sterile agar. 



(b) Bezangon prepared the medium as 

 follows: 



(1) Add 100.0 g. of chopped potatoes 

 to 200.0 cc. of a 4.0% glycerol 

 solution and boil in the autoclave 

 (time not given). 



(2) Separate the liquid from the pota- 

 toes (method not given). 



(3) Dissolve 6.0 g. NaCl and 50.0 g. 

 of agar in a liter of water in the 

 autoclave. 



(4) Add 50.0 cc. of the potato juice to 

 150.0 cc. of (3). 



(5) Tube in 2 to 3.0 cc. quantities. 



(6) Sterilize (method not given). 



(7) When ready for use melt the agar 

 and add an equal quantity of whole 

 or defibrinated human or rabbit 

 blood. (Temperature of the agar 

 not specified.) 



(8) Mix well. 



(c) Harvey prepared a similar medium as 

 follows: 



(1) Grate finely washed, peeled 

 potatoes. 



(2) Add 100.0 g. to 100.0 cc. water. 



(3) Heat the mixture 20 minutes to a 

 temperature not exceeding 50°C. 



(4) Raise to boiling temperature. 



(5) Boil 10 minutes. 



(6) Pour the mixture onto a clean, 

 thick cloth. 



(7) Collect the fluid which drains thru 

 the cloth together with that ob- 

 tained by squeezing the cloth. 



(8) Filter the fluid collected thru 

 thick, filter paper. 



(9) Add the filtrate to an equal 

 quantity of distilled water. 



(10) Steam 60 minutes. 



(11) Add glycerol to 4.0%. 



(12) Mix well. 



(13) Filter. 



(14) Mix 10 parts (13) with 30 parts 

 0.6% NaCl solution and one part 

 agar. 



(15) Sterilize. 



(16) Distribute into test tubes. 



(d) Povitzky prepared the medium in the 

 same manner as Bordet and Gengou 

 using 2.0% glycerol as a final con- 

 centration instead of 1.0% and used 

 defibrinated or citrated horse blood 

 instead of defibrinated rabbit or 

 human blood. 



(e) Park, Williams and Krumwiede pre- 

 pared the medium as follows: 



(1) Add 500.0 g. sliced potatoes and 

 80.0 cc. glycerol to 1000.0 cc. water. 



(2) Heat in the autoclave at 15 pounds 

 pressure for 30 minutes. 



(3) Pour off the liquid. 



C4) To 500.0 cc. of the potato extract, 

 add 1500.0 cc. of a 0.6% salt solu- 

 tion and 60.0 g. agar. 



