830 



CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



Preparation : 



(1) Dissolve 2, 3 and 4 in 1. 



(2) Add (1) to one of the listed pulverized 

 materials. The solid materials are 

 placed in a Petri dish, and the solu- 

 tion added until they are about one- 

 half immersed. The following 

 "Starre" materials were used: 



Ouartz sand (Merck's sea sand, washed 



and heated to glowing). 

 Glass powder (pulverized Erlenmeyer 



Kavlin (Merck) 



Clay powder (pulverized pottery) 



Clay plates (pieces of pottery) 



Pieces of porcelain 



Pumice stone powder 



Kieselguhr 



Talcum 



Asbestos powder 



Marble powder 



Marble 



Prepared chalk 



CaCOs (precipitated Merck's) 



Magnesium gypsum plates (1 part 

 MgCOs -I- 99 parts gypsimi, according 

 to Omelianski). 



Blood charcoal (Merck). 



Charcoal powder. 



Soot. 



Pieces of sponge. 

 Sterilization : Not specified. 

 Use: See medium 329. 

 Variants: The author used media 329 or 



560 instead of the solution given above. 

 Reference: Mortensen (1909 p. 532). 



2530. Wojtkiewicz's Soil Medium 



Constituents : 



1. Water. 



2. Soil. 

 Preparation : 



(1) Fill 7.0 cm. wide and 20.0 cm. high 

 glass cylinders with 500.0 g. of sifted 

 soil that has been moistened with 

 25.0% water. 



(2) Pass 10 liters of CO a free air thru the 

 cylinder per day. 



Sterilization: Not specified. 



Use: To study carbon dioxide production 

 by soil forms. The author collected the 

 formed CO a in a Liebig's potassium 

 apparatus. Sherman studied the activi- 



ties of protozoa in the soil and their in- 

 fluence upon bacterial flora. 

 Variants : 



(a) Sherman sterilized soil with a mois- 

 ture content of 17.0% or 18.0%. 



(b) Sherman prepared soil as follows: 



(1) Place various soils in suitable con- 

 tainers. 



(2) Cover with layer of non-absorbent 

 cotton between layers of cheese 

 cloth. 



(3) Sterilize in autoclave at 15 pounds 

 pressure for one hour. 



References: Wojtkiewicz (1914 p. 260), 

 Sherman (1916 pp. 45, 47). 



2531. MakrinofE's Carbonate Soil Medium 



Constituents : 



1. Nitrite forming solution. 



2. MgCO,. 



3. Soil. 

 Preparation : 



(1) To each 10.0 g. of dry MgCO, add 

 0.25, 0.75, 1.0, 1.75, 2.5, 3.5 5.0 or 

 6.5 g. of dry soil. 



(2) Mix well. 



(3) Add usual substrata for nitrite forma- 

 tion (composition not given) until a 

 semi fluid mass is formed. 



(4) Place in test tubes and slant. 



(5) Place a strip of absorbing paper in 

 the tube touching the mixture and 

 allow to stand over night. 



(6) Solidification takes place. 



(7) To each tube of sterile (6) add 3.0 to 

 5.0 cc. sterile substrata for nitrite 

 formation. 



Sterilization: Sterilize (6) for 30 minutes at 

 120°C. Method of sterilization of nitrite 

 forming solution not given. 



Use: To study nitrite production. The 

 author reported that following inocula- 

 tion growth took place, causing the 

 MgCO I to become liquid. This caused 

 the colonies to be deep in the substrata. 



Reference: Makrinoflf (1909 p. 417). 



2532. Wichers' Ammonium Sulphate 

 Permutite Medium 



Same as medium 2519 but use 10.0 g. of 

 calcium permutite instead of 24.0 g. of eand 

 in each flask. 



