CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



423 



3. Glucose 50.0 g. 



4. KH2PO4 0.5 g. 



5. MgS04 0.2 g. 



(c) Beijerinck also used the following 

 medium: 



1. Water 1000.0 g. 



2. Glucose 100.0 g. 



3. KH2PO4 1.0 g. 



4. MgS04 1.0 g. 



5. Agar 20.0 g. 



(d) Brown added a trace of FeaSOi to the 

 basic medium and added 0.05 g. pep- 

 tone. This medium was modified as 

 follows: 



(1) Substitute 0.05 g. urea for peptone 

 (Brown urea agar). 



(2) Substitute 0.05 g. asparagin for 

 peptone (Brown asparagin agar). 



(3) Substitute 0.1 g. casein for peptone 

 (Brown casein agar A). 



(4) Substitute 0.1 g. albumin for pep- 

 tone (Brown albumin agar A). 



(5) Omit the peptone from (1) and 

 substitute 10.0 g. of albumin for 

 the peptone (Brown albumin 

 agar B). 



(6) Substitute 20.0 cc. of extract of 

 humus (method of preparation not 

 given) for peptone (Brown Arti- 

 ficial humus agar A). 



(7) Substitute 10.0 cc. of extract of 

 humus (method of preparation not 

 given) for peptone (Brown Arti- 

 ficial humus agar B). 



(8) Substitute 20.0 cc. of humus ex- 

 tract (method of preparation not 

 given) for peptone and add 6.0 g. 

 K2HPO4 (Brown Artificial humus 

 agar C). Reaction is 0.5% acid. 



(9) Substitute 10.0 cc. of humus ex- 

 tract (method of preparation not 

 given) for peptone and add 3.0 g. 

 K2HPO4 (Brown Artificial humus 

 agar D). Reaction is 0.5% acid. 



(10) Same as (9) but omit the dextrose 

 from the agar. Reaction is 0.5% 

 acid (Brown Artificial humus 

 agar E). 



(11) Substitute 10.0 cc. of humus ex- 

 tract neutralized with HCl for 

 peptone (Brown Artificial humus 

 agar F). 



(12) Substitute 25.0 cc. of humus ex- 



tract neutralized with N/1 HCI 

 for peptone (Brown Artificial 

 humus agar G). 



(13) Substitute 0.05 g. casein for pep- 

 tone (Brown casein agar B). 



(14) Substitute 0.05 g. albumin for pep- 

 tone (Brown albumin agar C). 



(15) Substitute 0.5 g. albumin for pep- 

 tone (Brown albumin agar D). 



(16) Substitute 1.0 g. albumin for pep- 

 tone (Brown albumin agar E). 



(17) Substitute 0.5 g. casein for pep- 

 tone (Brown casein agar C). 



(e) Greaves studied the bacterial count 

 of soil on a medium composed of the 

 following constituents: 



1. Distilled water 1000.0 cc. 



2. Dextrose 10 g 



3. K2HPO4 0^5 g' 



4. MgS04 0.2 g. 



5. Agar (powdered) 20.0 g. 



References: Lipman and Brown (1910 



p. 447), Dombrowski (1910 p. 380), Beij- 

 erinck (1911 pp. 164, 165), Brown (1913 

 p. 498), Greaves (1914 p. 447). 



1440. Beijerinck's Glucose Agar 



Same as medium 185, but solidified by the 

 addition of 2.0% agar. 



1441. Heinemann's Glucose A^ar 

 Constituents: 



1. Distilled water 1000.0 cc. 



1.0 g 

 0.5 g 

 0.01 g 

 0.01 g 

 0.01 g 



2. KH2PO4 



3. MgSOi. 



4. NaCl . . 



5. FeS04. . 



6. MnS04. 



7. Glucose 20.0 



8. Agar 2O.O g 



Preparation : 



(1) Dissolve 2, 3, 4, 5, 6 and 7 in 1. 



(2) Dissolve 20.0 g. of agar in (1). 



Sterilization: Sterilize in the autoclave. 



Use: To study the assimilation of atmos- 

 pheric nitrogen. 



Reference: Heinemann (1922 p. 39). 



1442. Miinter's Basal Salt Agar 



Same as medium 164, but solidified by the 

 addition of 1.2% agar. Also solidify me- 

 dium 140 by the addition of 1.2% agar. 



