抄録
The screened strain that exhibited the highest level of polygalacturonase (PGase) activity based on coffee pectin was selected and identified as Aspergillus tubingensis. Sucrose (2%) and sodium nitrate (3%) were the best carbon and nitrogen sources, respectively, for the strain’s production of PGase. At 35°C and an initial pH of 4 as culture conditions, the strain showed the highest level of PGase production (15.9 U/mL). The highest activity of purified PGase-1 was observed at 60°C and pH 5. PGase-I activity was highly enhanced by Ca2+, Mn2+, and Ba2+. PGase-I was thermally stable at 50°C, with a half-life of 4 h. High stability was observed after 24 h incubation at pH levels from 3 to 7. The elimination of coffee mucilage was obviously improved by treating with this enzyme.
