o-Nitrophenyl-b-D-Galactopyranoside (ONPG) Test Principle, Procedure
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o-Nitrophenyl-b-D-Galactopyranoside (ONPG) Test Overview ONPG Test Purpose ONPG Test Principle Requirements for ONPG Test ONPG broth Composition Ingredients Gms / Litre Casitose (Equivalent to Casein Peptone) 7.500 O-Nitrophenyl-β-D-galactopyranoside 1.500 Disodium hydrogen phosphate 0.350 Sodium chloride 3.750 Final pH ( at 25°C) 7.5±0.2 ONPG Test Procedure ONPG broth method ONPG disk method Discs made of ONPG-impregnated … Read more