CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



195 



2. Yeast extract 10.0 g. 



3. Peptone 10.0 g. 



Preparation: 



(1) Stir 10.0 g. of yeast extract (commer- 

 cial product from E. stock) and boil 

 for one hour in a steamer. 



(2) Clarify by repeated filtering thru 

 paper, by addition of serum, or egg 

 white, or by the addition of 5.0 cc. 

 liquid Ferric oxychlorate, and then 

 filtering. 



(3) Add 1.0% peptone but no NaCI as the 

 extract contains 50.0% NaCl. 



Sterilization: Not specified. 



Use: Meat infusion substitute for the 

 preparation of special media, Endoagar, 

 lactose litmus agar, etc. Do not heat 

 over 100°C. or a brown color and a pre- 

 cipitate will develop. 



Reference: Ickert (1918 p. 186). 



695. Ickert's Yeast Infusion Peptone 

 Solution 



Constituents: 



1. Water 1000.0 cc. 



2. Pressed yeast 30.0 g. 



3. Peptone 10.0 g. 



4. NaCI 5.0 g. 



Preparation: 



(1) Suspend 30.0 g. (40.0 g. when pre- 

 paring agar medium) of pressed yeast 

 in 1 liter of water. 



(2) Allow to infuse for one hour. 



(3) Boil for 2 hours in the steamer. 



(4) Clarify by the addition of 5.0 cc. of 

 ferric oxychlorate while hot, and filter 

 twice thru a double filter. 



(5) Add 0.5% NaCI and 1.0% peptone. 

 Sterilization: Not specified. 



Use: Meat infusion substitute for the 

 preparation of special media, Endo, lit- 

 mus lactose agar, etc. Do not heat over 

 100 °C. or a brown color and a precipi- 

 tate will form. 



Reference: Ickert (1918 p. 186). 



696. Fred and Peterson's Yeast Infusion 

 Peptone Solution 



Constituents: 



1. Fresh yeast water extract. . 1000.0 cc. 



2. K2HPO4 5.0 g. 



3. Difco peptone 5.0 g. 



4. Xylose 20.0 g. 



5. Brom cresol purple 



Preparation : 



(1) Preparation or composition of fresh 

 yeast water extract not given. 



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



(3) Adjustment of reaction not given. 



(4) Flask in 250.0 cc. lots. 



(5) When inoculating add a few drops of 

 brom cresol purple. 



Sterilization: Sterilize at 15 pounds pres- 

 sure for 30 minutes in the autoclave. 

 Use: To determine fermentation of xylose. 

 Reference: Fred and Peterson (1920 p. 540). 



697. Ventre's Basal Yeast Ash Peptone 



Solution 



Constituents : 



1. Water 1000.0 cc. 



2. Glucose 170.0 g. 



3. Malt dust extract 2.0 



4. Peptone (malto peptone).. 0.5 



5. Yeast ashes 0.5 g. 



6. (NH4)2HP04 1.0 g. 



7. K0CO3 1.85 g. 



Preparation : 



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



(2) Add one of the added nutrients and 

 1.85g. of K.COsto (1). 



Sterilization: Sterilize by heating in the 

 autoclave at 120°C., by filtration thru a 

 candle or by treating with H..SO4 (250 mg. 

 H2SO4 per liter) (details of method not 

 given). 



Use: Cultivation of yeast. 



Added nutrients and variants: 



(a) The author added one of the fol- 

 lowing: 



tartaric acid 4.0 g. 



malic acid 5.0 g. 



citric acid 0.5 g. 



(b) Used the basic solution without the 

 addition of other materials. 



Reference: Ventre (1914 p. 198). 



698. Henneberg's Glucose Yeast Infusion 



Solution 



Constituents: 



1. Yeast infusion (1.0%) 1000.0 cc. 



2. Peptone (1.0%) 10.0 g. 



3. Glucose (5.0%) 50.0 g. 



Preparation: 



(1) Prepare a 1.0% yeast infusion 

 (method not given). 



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

 Sterilization: Not specified. 



