CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



809 



2475. Sullivan's Basal Glycerol Silicate 

 Jelly 



Constituents: 



1. Water 1000.0 cc. 



2. Sodium silicate (4.0%) 40.0 g. 



3. Glycerol (3.5%) 35.0 g. 



4. H3PO4 (10.0%) 

 Preparation: 



(1) Add to the water about 4.0% sodium 

 silicate. 



(2) Add 3.5% glycerol which prevents the 

 silicic acid from throwing out its 

 water. Mix. 



(3) Add drop by drop with frequent stir- 

 ring enough of a 10.0% solution of 

 H3PO4 sterile (2) to render slightly 

 acid to phenolphthalein. 



(4) Medium solidifies at room tempera- 

 ture in about 30 minutes. In the 

 sterilizer the medium is solidified in 

 from 5 to 10 minutes. 



Sterilization: Method not given. 

 Use: To study pigment production. 

 Variants: A solution of any desired salts 



may be used instead of water. 

 Reference: Sullivan (1905-06 p. 118). 



2476. Fermi's Solution Silicate Jelly 

 (Smith) 



Constituents : 



1. Water 100-0 ««• 



2. MgS04 0.2g. 



3. KH2PO4 10 g. 



4. Ammonium phosphate 10.0 g. 



5. Glycerol 45.0 g. 



6. HCl 500.0 cc. 



7. Sodium silicate 500.0 cc. 



Preparation : 



(1) Add drop by drop 500.0 cc. of sodium 

 silicate (sp. gr. 1.09) to 500.0 cc. of 

 HCl (sp. gr. 1.10° Beaume) stirring 

 the mixture constantly with a glass 

 rod. 



(2) Place in a collodion sac and dialyze 

 in running water until all traces of 

 salt have been removed. 



(3) Dissolve 2, 3 and 4 in 100.0 cc. of 

 freshly boiled distilled water. 



(4) Add 45.0 g. glycerol to (3). 



(5) Boil (3) for a minute or 2 to drive off 

 the absorbed air. 



(6) Cool (5) to 50°C. 



(7) Add 90.0 cc. of (4) to 500.0 cc. of (6). 



It is necessary to have (4) free from 

 air. Either boil and cool or remove 

 the air using an air pump. Mix 

 thoroly by stirring with a clean glass 

 rod. 

 (8) Pipette quickly into tubes. 



Sterilization: Autoclave at 110°C. for 

 15 minutes. 



Use : Synthetic medium for plant parasites 



Reference: Smith (1905 p. 39). 



2477. Doryland's Basal Acetic Acid Silicate 

 Jelly 

 Same as medium 2474 but containing 

 153.5 cc. acetic acid instead of glucose. 

 The acetic acid is added with the acids in 

 step (7) and not at the end, as in the case 

 of glucose. 



2478. Waksman and Carey's Cellulose 

 Silica Jelly 



Constituents : 



1 Distilled water 100.0 cc. 



2. (NH4)2HP04 5.0 g. 



3. MgS04 1-0 g- 



4. FeS04 0.02g. 



5. KCl 10 g. 



6. HCl 



7. Potassium silicate 



8. Cellulose (filter paper) 5.0 g. 



9. CaCOs 

 Preparation: 



(1) Prepare a normal solution of HCl 

 and an equivalent solution of C.P. 

 potassium silicate solution (about 

 10% silicate). 



(2) Place 5.0 cc. portions of the acid in 

 a series of tubes, and add varying 

 quantities of silicate (4.5, 4.75, 5.0, 

 5.25, 5.75, 6.0, etc. cc). 



(3) Mix and pour into a series of dishes. 



(4) Select the mixture that solidifies in 

 from two to five minutes. 



(5) Dilute the silicate solution with dis- 

 tilled water so that equal volumes of 

 the silicate and HCl give a gel in 

 the desired period of time. 



(6) Pour from 100.0 cc. to 200.0 cc. of 

 silicate solution into an equal 

 volume of the acid solution and mix 

 thoroly. 



(7) Pour (6) into the lower halves of 

 petri dishes in a layer 3 to 4 mm. 

 deep. 



