CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



429 



(2) Add a slight excess of copper car- 

 bonate. 



(3) Shake vigorously. 



(4) Allow to stand over night and then 

 siphon off the supernatant solution. 



(5) Add 15.0 g. of unwashed sheet filter 

 paper. 



(6) Shake occasionally until the paper 

 is dissolved. 



(7) Dilute to 10 liters and add slowly a 

 one to five solution of hydrochloric 

 acid with vigorous shaking until the 

 precipitation of the cellulose is 

 complete. 



(8) Dilute to 20 liters, allow the cellu- 

 lose to settle and decant the super- 

 natant liquid. 



(9) Wash by repeated changes of water, 

 adding HCl each time until the 

 copper color disappears. Then wash 

 with water alone until the solution 

 is free from chlorine. 



(10) Allow to settle several days and 

 decant as much of the clear solution 

 as possible. 



(11) If the cellulose percentage is too 

 low centrifuge a portion of the fluid 

 to bring the cellulose content up to 

 one per cent. 



(12) Dissolve 4, 5, 6, 7 and 8 in 1000.0 cc. 

 of tap water. 



(13) Mix 500.0 cc. of (11), 500.0 cc. of (12). 



(14) Dissolve 10.0 g. of agar in (13). 

 Sterilization: Method not given. 



Use: Cultivation of organisms fermenting 



cellulose. 

 Variants : 



(a) The author prepared a similar me- 

 dium using potato starch instead of 

 cellulose as the polysaccharide. The 

 medium was prepared as follows : 



(1) To 800.0 cc. of boiling water add 

 10.0 g. of potato starch suspended 

 in cold water. 



(2) Evaporate by boiling to 500.0 cc. 



(3) Dissolve 1.0 g. K2HPO4, 1.0 g. 

 MgS04, 1.0 g. NaCl, 2.0 g. 

 (NH4)2S04, and 2.0 g. CaCOj in 

 1000.0 cc. of water. 



(4) Mix 500.0 cc. (2) with 500.0 cc. (3). 



(5) Dissolve 10.0 g. of agar in (4). 



(6) Sterilization not specified. 



(b) Tanner used one-half the amounts of 

 salts and dissolved them in 500.0 cc. 



of water instead of 1000.0 cc. as indi- 

 cated by Kellerman and McBeth. 

 Tanner then mixed equal parts salt 

 solution on cellulose solution. 



(c) Tanner prepared starch agar by dis- 

 solving one-half the quantity of salts 

 given in variant (a), step (3), in 

 500.0 cc. tap water. Then Tanner 

 mixed equal parts of salt solution 

 and starch water and proceeded as 

 in variant (a). 



(d) Giltner prepared a starch agar as 

 follows: 



(1) Dissolve 1.0 g. K2HPO4, 1.0 g. 

 MgS04-7H20, 1.0 g. NaCl, 2.0 g. 

 (NH4)2S04, and 2.0 g. CaCOa in 

 1000.0 cc. of water. 



(2) Add 10.0 g. washed agar. 



(3) Weigh. 



(4) Boil over a free flame until the 

 solution of the agar is complete. 



(5) Weigh and make up the loss in 

 weight with boiling water. 



(6) Make a smooth paste of 10.0 g. of 

 potato starch or other starch in a 

 little cold water. 



(7) Add 800.0 cc. of boiling water 

 to (6). 



(8) Concentrate to 500.0 cc. by boiling. 



(9) Mix (5) and (8) and boil a few 

 minutes. 



(10) Strain thru two thicknesses of 

 cheese cloth. 



(11) Add 1.5% china blue rosolic acid 

 for indicator. 



(12) Tube, taking care to keep the 

 CaCOs well mixed with the media. 



(13) Sterilize (method not given). 



(e) Khouvine prepared a cellulose in the 

 same manner as Kellerman and 

 McBeth and dissolved 20.0 g. agar in 

 1000.0 cc. of water by heating. The 

 inorganic salts, as used by Keller- 

 man and McBeth, were dissolved in 

 the agar solution. Five hundred 

 cubic centimeters of the cellulose 

 solution was then added to the agar 

 solution, mi.xed well, tubed and steri- 

 lized at 110° for 15 minutes. 



(f) Khouvine prepared a starch agar in 

 the following manner: 



(1) Prepare a paste with 10.0 g. of 

 potato starch in a little cold water. 



(2) Add (1) to 800.0 cc. of boiling water. 



