CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



495 



(8) Collect the fluid which drains 

 thru the cloth together with that 

 obtained by squeezing the meat 

 in the cloth. 



(9) Filter the fluid collected thru 

 well-wetted, thick filter paper. 



(10) Add to the filtrate— 10.0 g. pep- 

 tone, 5.0 g. sodium chloride. 



(11) Steam or boil 45 minutes. 



(12) Bring the volume up to 1000.0 cc. 

 by the addition of water. 



(13) Cut up 20.0 g. fiber agar into 

 small pieces. 



(14) Add to 1000.0 cc. hot bouillon 

 (12). 



(15) Bring the agar into solution with 

 heat after having been allowed to 

 soak 2 hours in the hot bouillon. 



(16) Estimate and adjust the reaction 

 to a definite pH value or faintly 

 alkaline to litmus or 1.0% acid 

 to phenolphthalein. 



(17) Steam 30 minutes. 



(18) Clarify and filter. 



(a) Beat up the white of one or two 

 eggs along with the crushed 

 shells in about 20.0 cc. water. 



Note: Raw meat juice, 

 15.0 cc. per liter of medium, 

 may be substituted for white of 

 egg. 



(b) Add to the medium little by 

 little before filtration and at a 

 temperature not exceeding 60°C. 



(c) Stir to mi.x. 



(d) Steam 30 minutes. 



(e) Remove from steamer and shake 

 well to mix. 



(f) Steam again 15 minutes. 



(g) Filter in the steamer thru thick 

 filter paper, or thru two layers 

 of absorbent cotton wool. 



(h) Refilter, if necessary, the first 

 portion of the filtrate. 



(19) Distribute into test tubes. 



(20) Sterilize in the steamer or auto- 

 clave. 



(x) Harvey (1921-22). 



(1) Mince 250.0 g. fat-free beef with 

 500.0 cc. of water. 



(2) Heat the mixture 20 minutes over 

 a free flame, at a temperature not 

 exceeding 50°C. 



(3) Skim off fat floating on the sur- 

 face. 



(4) Raise the temperature to boiling 

 point. 



(5) Boil 10 minutes. 



(6) Pour the mixture on to a wet, 

 thick, clean cloth. 



(7) Add 2.5 g. XaCl to the filtrate. 



(8) Bring the volume up to 1000.0 cc. 

 by the addition of water. 



(9) Estimate and adjust the reaction. 



(10) Steam 30 minutes. 



(11) Filter, while hot, thru well- 

 wetted, thick filter paper. 



(12) Place 15.0 g. fiber agar in 500.0 cc. 

 tap water. 



(13) Wash the agar well by squeezing 

 it thru the hands. 



(14) Decant and reject the dirty 

 water. 



(15) Replace with the same amount of 

 clean tap water. 



(16) Heat over a free flame with con- 

 stant stirring to dissolve the agar. 



(17) Add peptone 5.0 g., sodium 

 chloride 2.5 g. 



(18) Add to 500.0 cc. of meat extract 

 (11), 10.0 g. egg albumin which 

 has been made into a paste or 

 suspension with a little of the 

 meat infusion. 



(19) Add the dissolved agar slowly to 

 the meat extract thus prepared, 

 with constant stirring. 



(20) Steam 60 minutes or heat 45 min- 

 utes at 120°C. 



(21) Bring the volume to 1000.0 cc. 

 by the addition of water. 



(22) Estimate and adjust the reaction. 



(23) Boil 15 minutes over a free flame. 



(24) Make up for any loss of volume 

 by addition of water. 



(25) Filter, while hot, thru well- 

 wetted, thick filter paper by 

 placing filter funnel, stand, and 

 receptacle for filtrate in the 

 steamer and steaming till filtra- 

 tion is completed. 



(26) Distribute filtrate into flasks or 

 test tubes. 



(27) Sterilize in the steamer or auto- 

 clave. 



(y) Harvey (1921-22). 



(1) Soak 10.0 g. purified agar (see me- 

 dium 1401 for preparation) in 

 500.0 cc. of Harvey's Infusion 



