P nitrophenyl β d glucopyranoside

Crude enzyme extracts from the organisms were assayed for a-galactosidase activity according to the method of Scalabrini et al. (1998) (link). The enzyme assay is based on the principle that when α-galactosidase enzyme acts on the substrate p-nitrophenyl-α-D-galactoside (HiMedia, India), a colorimetric reaction takes place which releases p-nitrophenol (pNP) in the medium. $\beta$ -glucosidase activity was determined by measuring the rate of hydrolysis of p-nitrophenyl $\beta$ -D-glucopyranoside (HiMedia, India) according to the method of Otieno and Shah (2007) (link) and Scalabrini et al. (1998) (link). The amount of p-nitrophenol released was measured spectrophotometrically using a UV–Vis spectrophotometer (Systronics, Ahmedabad) at 410 nm.

Fungal culture media (yeast extract glucose agar and potato dextrose agar), birch wood xylan, carboxymethyl cellulose (CMC), p-nitrophenyl–β-D-glucopyranoside, and standard sugars (HPLC-grade) were purchased from HiMedia laboratories Ltd, Mumbai, India. Veratryl alcohol was purchased from Sigma Aldrich Co, USA. 2, 2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) was purchased from MP Biomedicals, USA. All other laboratory reagents were purchased from SD-Fine chemicals Ltd, Mumbai, India.