Chemo-Enzymatic Production of 4-Nitrophenyl-2-acetamido-2-deoxy-α-D-galactopyranoside Using Immobilized β-N-Acetylhexosaminidase

α-Nitrophenyl derivatives of glycosides are convenient substrates used to detect and characterize α-N-acetylgalactosaminidase. A new procedure combining chemical biocatalytic steps was developed prepare 4-nitrophenyl-2-acetamido-2-deoxy-α-D-galactopyranoside (4NP-α-GalNAc). The α-anomer prepared through synthesis an anomeric mixture followed by selective removal the β-anomer using specific enzymatic hydrolysis. Fungal β-N-acetylhexosaminidase (Hex) from Penicillium oxalicum CCF 1959 served this purpose owing its high chemo-and regioselectivity towards β-anomeric N-acetylgalactosamine (GalNAc) derivative. kinetic measurements hydrolytic reaction showed that enzyme not inhibited substrate or products. immobilization Hex in lens-shaped polyvinyl alcohol hydrogel capsules provided a biocatalyst with very good storage operational stability. immobilized retained 97% initial activity after ten repeated uses 90% 18 months at 4 °C. Immobilization inactivated 65% activity. However, effectiveness factor mass transfer phenomena approached unity indicating negligible limitations.