E. Coli

3.1.4.Solutions and indicators in biochemical
identification (Cruickshank et al., 1975):
3.1.4.1. Oxidase reagent (Bio-Merieux, 1980)
Freshly prepared 1%solution of tetra methyl-p-phenylene diamine
dihydrochloride was used to test for oxidase production.
3.1.4.2. Kovac's reagent:
Pdimethylaminobenzaldhyde 10 g
Amyl alcohol 150 ml
Concentrated HCl 50 ml
3.1.4.3. Methyl Red Reagent: (M.R)
Methyl red 0.1 g
Ethyl alcohol 95% 300.0 ml
Distilled water 200.0 ml
3.1.4.4.Voges-Proskauer (V.P.) test reagents:
To 5ml of a 48-hours at 37°C, 3ml of alcoholic solution of naphthol
and 1ml of 40% of potassium hydroxide solutions were
added. Pink colored ring developed withen 10-15 min. while negative
if there is no pink ring.
3.1.4.5. Urea solution (40%) (Oxoid, sr20)
3.1.4.6. H2S production:
Triple sugar iron (T.S.I) (oxoid) examination was done daily up
to the 7 th day for detection of H2S production as well as for gas
production.
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