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CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



2437. Dorset's Egg Medium (Abel) 



Constituents: 



1. Physiological salt solution.. . 100.0 cc. 



2. Egg 300.0 cc. 



Preparation : 



(1) Wash absolutely fresh eggs in dilute 

 formalin. 



(2) Allow the shells to dry and break the 

 eggs into a sterile dish. 



(3) Thoroly mix the yolk and albuminous 

 portion by gentle stirring. 



(4) Strain the mixture thru sterile gauze. 



(5) Add one part sterile physiological 

 salt solution (0.85% NaCl) to 3 parts 

 (4). 



(6) Tube. 



(7) Coagulate in 3 to 5 minutes by heat- 

 ing in the steamer. 



Sterilization: Sterilize the tubes by heating 

 at 105° for 20 minutes on each of 2 succes- 

 sive days. Screw all of the valves of the 

 autoclave down before starting to heat. 



Use: Cultivation of tubercle bacilli. 



Variants : 



(a) Abel stated that sterile glycerol 

 bouillon might be added to the 

 medium to prevent drying. 



(b) Harvey prepared the medium as 

 follows: 



(1) Clean thoroly the eggs to be used. 



(2) Wash with 5.0% carbolic acid. 



(3) Allow to dry partially. 



(4) Heat the ends of the eggs gently 

 in the flame to dry them. 



(5) Pierce, with sterile precautions, 

 both ends. 



(6) Blow the whole contents of the 

 eggs into a sterile, wide-mouthed, 

 glass stoppered bottle containing 

 glass beads. 



Note : The eggs may be carefully 

 broken and the contents allowed 

 to fall into the bottle. 



(7) Add* 1 volume 0.85 sterile salt 

 solution for each 3 volumes egg 

 contents. 



♦Note: If desired 3.75 cc. N/1 

 sodium hydroxide per 100.0 cc. egg 

 mixture may be added and also 

 1-0% glucose at this stage. 



(8) Shake well to mix. 



(9) Strain thru cloth. 



Note: At this stage, if desired, 

 some drops of alcohol basic fuchsin 



to give a slight pink color to the 

 medium may be added. 



(10) Distribute into test tubes. 



(11) Coagulate. 



(12) Fill in each test tube 0.85 sterile 

 salt solution to cover the medium. 



(13) Sterilize. 



Note: It is very usual to dis- 

 pense with the addition of salt 

 solution and subsequent steriliza- 

 tion. In that case sterility should 

 be tested before use by incubation 

 for 48 hours. 



(14) Pour off the salt solution at the 

 time of use. 



References: Abel (1912 p. 97), Harvey 

 (1921-22 p. 84). 



2438. Soparkar's Glycerol Egg Medium 



Constituents : 



1. Water with 5.0% glycerol. 72.0 cc. 



2. Eggs 1.0 dozen 



Preparation : 



(1) Sterilize surface of one dozen eggs by 

 pouring boiling water over them. 



(2) Break the shell with sterile forceps 

 and pour contents into a sterile flask. 



(3) Add 6.0 cc. of (sterile ?) water con- 

 taining 5.0% glycerol for each egg 

 (72.0 cc.) and thoroly mix by con- 

 tinued shaking. 



(4) Strain material thru sterile muslin 

 and distribute in tubes. 



(5) Heat in inspissator on the first day 

 up to about 90°C. for 3 hours till the 

 medium becomes solid. Then at 

 72°C. for 3 hours on each of two 

 succeeding days. 



Sterilization: Method not given. 

 Use: Cultivation of tubercle bacilli. 

 Reference: Soparkar (1916-17 p. 34). 



2439. Lubenau's Glycerol Egg Medium 



(Abel) 



Constituents: 



1. Physiological salt solution... 100.0 cc. 



2. Egg 300.0 cc. 



3. Glycerol (6.0%) 6.0 g. 



Preparation : 



(1) Wash absolutely fresh eggs in un- 

 diluted formalin. 



(2) Allow the shells to dry and break the 

 eggs into a sterile dish. 



