494 



CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



(2) Adjust reaction so that it is 

 neutral to phenolphthalein. 



(3) Tube in 8 to 10.0 cc. quantities. 



(4) Autoclave at 15 pounds for J hour. 



(5) To transfer cultures, a semi-solid 

 agar culture is melted and 1.0 cc. 

 portions transferred to fresh 

 semi-solid melted agar tube. 



(u) Meier (1918). 



(1) Boil 500.0 g. of fat and tendon 

 free beef in 1 liter of water. 



(2) Filter. 



(3) Dissolve 15.0 g. agar, 10.0 g. 

 Witte's peptone and 5.0 g. NaCl 

 in the filtrate. 



(4) Neutralize by the addition of 

 KOH. Add KOH until turmeric 

 paper is turned quite weakly 

 brownish red. 



(5) Sterilization not specified, 

 (v) Harvey (1921-22). 



(1) Mince finely fat-free beef. 



(2) Add 500.0 to 1000.0 cc. distilled 

 water or clear tap water. 



(3) Heat the mixture 20 minutes 

 over a free flame at a temperature 

 not exceeding 50°C. 



(4) Skim off fat floating on the sur- 

 face. 



(5) Raise the temperature to boiling 

 point. 



(6) Boil 10 minutes. 



(7) Pour the mixture onto a wet, 

 thick, clean cloth. 



(8) Collect the fluid which drains 

 thru the cloth together with that 

 obtained by squeezing the meat 

 in the cloth. 



(9) Add 10 g. peptone 5.0g XaCl. 



(10) Mix fiber agar 1 part, glacial 

 acetic acid 0.05 parts, and water 

 2 parts. 



(11) Allow the agar to soak in the 

 acidified water 15 minutes. 



(12) Remove the fiber agar and wash 

 thoroly with water imtil quite 

 free from any trace of acid reac- 

 tion to litmus paper. 



(13) Squeeze in a cloth to get rid of 

 excess of water. 



(14) Add (13) to (9). 



(15) Steam gently 2^ hours to bring 

 the agar thoroly into solution. 



Note: Or heat 45 minutes at 

 118°C. 



(16) Bring the volume up to 1000.0 cc. 

 by the addition of hot water. 



(17) Estimate and adjust the reaction 

 to a definite pH value, or to 

 faintly alkaline to litmus or 

 1.0% acid to phenolphthalein. 



(18) Steam 30 minutes. 



(19) Filter, while hot, thru well- 

 wetted, thick filter paper or two 

 paper or two layers of absorbent 

 cotton wool, by placing filter 

 funnel, stand, and receptacle for 

 filtrate in the steam sterilizer 

 and steaming till filtration is 

 complete. 



Note: If filtration thru paper 

 is not sufficient to give a clear 

 medium, clarify with white of 

 egg or other clearing agent. 



(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 sub- 

 stituted 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 mix. 



(d) Steam 30 minutes. 



(e) Remove from steamer and shake 

 up well to mix. 



(f) Steam again 15 minutes. 



(g) Filter in the steamer thru thick 

 filter paper, or thru two layers 

 of absorbent cotton, 



(h) Refilter, if necessary, the first 

 portion of the filtrate. 

 (20) Distribute into flasks on test 

 tubes, 

 (w) Harvey (1921-22). 



(1) Mince finely fat-free beef. 



(2) Add 500.0 g. to 1000.0 cc. dis- 

 tilled water or clear tap water. 



(3) Heat the mi.xture 20 minutes over 

 a free flame at a temperature not 

 exceeding 50°C. 



(4) Skim off fat floating on the sur- 

 face. 



(5) Raise the temperature to boiling 

 point. 



(6) Boil 10 minutes. 



(7) Pour the mixture on to a wet, 

 thick, clean cloth. 



