ONPG Test – Principle, Procedure, Result, Uses

o-Nitrophenyl-b-D-Galactopyranoside (ONPG) Test Principle, Procedure

ONPG test is a rapid biochemical test used in microbiology to detect the presence of β-galactosidase enzyme in bacteria. It is used to identify organisms which can produce β-galactosidase but may not ferment lactose in routine lactose tests. Normally lactose fermentation needs two enzymes. One is lactose permease which transports lactose inside the cell. Another … Read more