Jump to Main Content
Production, purification and biochemical characterization of an exo-polygalacturonase from Aspergillus niger MTCC 478 suitable for clarification of orange juice
- Anand, Gautam, Yadav, Sangeeta, Yadav, Dinesh
- 3 Biotech 2017 v.7 no.2 pp. 122
- Aspergillus niger, acetone, chromatography, clarification (processing), copper, enzyme activity, fungi, industrial applications, molecular weight, orange juice, pH, polygalacturonase, silver, solid state fermentation, tea, temperature, wheat bran
- Polygalacturonases (PG) represent an important member of pectinases group of enzymes with immense industrial applications. A fungal strain Aspergillus niger MTCC478 was used for the production of polygalacturonase both under submerged and solid-state fermentation condition. Further its production was optimized under solid-state fermentation condition with media comprising of wheat bran and tea extract. Purification of an exo-PG was achieved by acetone precipitation (60–90%) and CM-cellulose column chromatography revealing 15.28-fold purification with a specific activity of 33.47 U/mg protein and 1.2% yield. A relative molecular mass of purified PG was approximately 124.0 kDa. The pH and temperature optimum was found to be 4 and 50 °C, respectively. The k cₐₜ and K ₘ value for degradation of PGA by the purified enzyme was found to be 194 s⁻¹ and 2.3 mg/mL, respectively. Cu²⁺ was found to enhance the PG activity while Ag⁺ completely inhibited the enzyme activity. The application of the purified PG in orange juice clarification was elucidated.