Pectinases from a new strain of Cladosporium cladosporioides (Fres.) De Vries isolated from coffee bean

Abstract

To examine tThe optimal conditions of cultivation for Cladosporium cladosporioides to produce and partially purify pectin methylesterase (PME) and polygalacturonase (PG) were examined under laboratory conditions . Activities of PME and PG were evaluated after 10, 15 and 20 days of incubation at 28°C in rice solid medium. Enzyme extraction was carried out by homogenization in buffer solutions at different pH (4, 5 and 6) followed by precipitation with ammonium sulfate [(NH4)2SO4] at 20, 40 and 60% saturation. After 10 days of incubation, the highest activities for PG (105.5 U/mL) and PME (1480 U/mL) in the crude extract was observed. Benzoate buffer (pH 4.0) was the best buffer for enzymes extraction. The final yield of 108.7% for PME and 10.6% for PG and a purification index of 14.2 and 1.4 for PME and PG, respectively, was obtained after saturation with 60%. The ideal conditions for obtained and pre-purification of PME and PG were 10 days of incubation, extraction with benzoate buffer pH 4.0 and precipitation with 60% of (NH4)2SO4. This is the first report on of pectinases pectinolytic enzymes produced by from C. cladosporioides and provides information about growth conditions for production and pre-purification of PME and PG.