CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



741 



pure sodium sulfite, either in solid 

 or concentrated clear solution. 

 (15) When material is dissolved mix well. 



Sterilization: Sterilize (13) in the steamer 

 for 20 minutes. Sterilize the final me- 

 dium for 20 minutes in the steamer. 



Use: To obtain bacterial counts in water. 

 Author reported that B. coli grew best 

 on medium containing lactose. B. typho- 

 sus and B. paratyphosus A and B and 

 Gartner's enteritidis grew best on man- 

 nitol or glucose. Shiga and dysentery- 

 bacilli developed best in glucose medium. 

 Cholera vibrio developed best in presence 

 of sucrose. When one of the sugars were 

 fermented by the organisms a red colony 

 developed. The medium should be color- 

 less when ready for use. On plating on a 

 series of media of this type one may 

 determine the kind of organisms present 

 in the water as well as the relative number. 



Added nutrients : The author added 10.0 g. 

 of lactose, mannitol or sucrose to (8). 



Variants : 



(a) Burger prepared a similar medium 

 using 20.0 g. Liebig's meat e.xtract, 

 20.0 g. Witte's Rostock's peptone, 

 10.0 g. NaCl, 200.0 g. gelatin, 2.0 g. 

 crystalline soda, 20.0 g. of the added 

 nutrients, 10.0 cc. of a saturated 

 alcoholic fuchsin solution and 5.0 g. 

 NaoSOa instead of the amounts indi- 

 cated. Water under investigation 

 may be added to the sterile medium. 



(b) Burger used the following amounts 

 of constituents in preparing a medium 

 in the same manner as above. Dis- 

 tilled water 750.0 cc, Liebig's meat 

 e.xtract 25.0 g., Witte's Rostock pep- 

 tone, 25.0 g., NaCl, 12.5 g., gelatin 

 250.0 g., saturated alcoholic fuchsin 

 solution 12.5 cc. NasSOj 6.25 g., 

 crystalline soda 2.5 g., and 25.0 g. of 

 one of the added nutrients. Water 

 under investigation may be added to 

 the sterile medium. 



Reference: Burger (1916-17 p. 478). 



2295. Tausz and Peter's Basal Ragit 

 Gelatin 



Constituents: 



1. Water 1000.0 cc. 



2. Ragit powder 22.0 g. 



3. Gelatin 100.0 g. 



Preparation: 



(1 ) Boil 22.0 g. of ragit powder with 1 liter 

 of water. 



(2) Add slowly 100.0 g. gelatin and bring 



to the boiling point. 



(3) The reaction is slightly alkaline. 



(4) Filter in the steamer. 

 Sterilization: Sterilize on 3 successive days 



for 30 minutes in streaming steam. 

 Use: Cultivation of Bacterium alipha- 



ticum, Bad. aliphaticutn liqucfaciens. 

 Added nutrients: The authors added 0.5% 



glucose, lactose or other nutrients. 

 Reference: Tausz and Peter (1919 p. 49). 



2296. Buchan's Basal Litmus Extract 

 Gelatin 



Constituents: 



1. Distilled water 850.0 cc. 



2. Peptone 20.0 g. 



3. Lemco 10.0 g. 



4. Gelatin 100.0 g. 



5. Litmus 

 Preparation : 



(1) Dissolve 2, 3, 4 and 10.0 g. of one of 

 the added nutrients in 1. 



(2) Add 10.0 cc. of a 5.0% KOH solution. 



(3) Tinge with litmus. 

 Sterilization : Not specified. 

 Use: To study fermentation. 



Added nutrients: The author added 10.0 g. 

 of any desired carbohydrate, alcohol, etc. 

 Reference: Buchan (1910 p. 107). 



2297. Bacto Nutrient Gelatin. (Dehydrated) 



Constituents: 



1. Distilled water 



2. Beef extract, Bacto 3.0 g. 



3. Peptone, Bacto 5.0 g. 



4. Gelatin, Bacto 120.0 g. 



Preparation : 



(1) Dissolve 128.0 g. of Bacto Nutrient 

 Gelatin (dehydrated) in 1000.0 cc. 

 distilled water by warming. 



(2) If sterilized at 15 pounds for 20 min- 

 utes pH = 6.6±. 



Sterilization: Sterilize for 20 minutes at 

 15 pounds pressure. 



Use: General culture medium. The au- 

 thors reported that the medium con- 

 forms to the "Standard Methods" 

 formula. 



Reference: Digestive Ferments Co. (1925 

 p. 10). 



