Dissolve this in a steamer and adjust the reaction to pH

7.5. After this, add 2% agar and melt in the autoclave

at 15 lb for 20 minutes. Clear with white of eggs. Than

add lactose 10 g and 1% solution of neutral red, 7–10 mL

to the media. Distribute in 200 mL flasks and sterilize

by steaming on 3 consecutive days in the Arnold’s

steam sterilizer. Organisms which produce acid from

lactose e.g. E. coli form rose pink colored colonies are

called lactose fermenters. Non-lactose fermenters, such

as Salmonella typhi, produce colorless colonies. Sodium

taurocholate is a bile salt, which inhibits the growth of

gram-positive bacteria and promotes the growth of enteric

gram-negative bacteria.

Lowenstein Jensen Medium

(For cultivation and differentiation of human and bovine

types of tubercle bacilli).

Mineral Salt Solution

Potassium dihydrogen phosphate 0.4%

Magnesium sulfate 0.04%

Magnesium citrate 0.1%

Asparagine 0.6%

Glycerol 2% (in distilled water)

Heat to dissolve. Boil the solution by placing a steamer

for 2 hours and allow it to cool overnight. 600 mL is a

convenient quantity to prepare. Asparagine gives the

source of nitrogen and glycerol the source of carbon. To

each 600 mL of mineral salt solution add 30 grams of potato

starch. A luxuriant growth can be obtained even without

the addition of potato starch. Eggs are washed with soap

water and immersed in 5% carbolic acid for half an hour.

After this wash the eggs in distilled water and break them

and filter. For 600 mL of mineral salt solution, 1000 mL of

egg fluid is required. Add 40 mL of 1% malachite green

solution to this solution. Inspissate the media at 80–85oC

for 50 minutes on three consecutive days.