Comprehensive evaluation of cell wall degrading enzymes produced by Aspergillus niger under various sucrose concentrations
摘要
The production of cell wall-degrading enzymes by the plant pathogenic fungus Aspergillus niger is of significant interest for both industrial and agriculture applications, particularly in the context of plant pathogenicity and biocontrol strategies. In this study, enzyme production was investigated using Murashige and Skoog (MS) medium supplemented with varying sucrose concentrations (1, 3, and 5%), using sucrose as the sole carbon source. Enzymatic activity was utilized in extracellular, cytoplasmic, and wall-bound fractions, focusing on different enzymes, such as polygalacturonase, xylanase, α/β-galactosidase, and β-glucosidase, for various time periods. Polygalacturonase exhibited the highest enzymatic activity, with peak extracellular activity of 95 U/mL at 72 h in the 3% sucrose condition, followed by a decrease in activity at higher sucrose concentrations. Xylanase activity peaked at 72 h in the 5% sucrose medium, reaching 45 U/mL. Both α-galactosidase and β-glucosidase showed moderate activity, with α-galactosidase reaching 20 U/mL and β-glucosidase 15 U/mL under the 1% sucrose condition. The extracellular fractions consistently displayed the most significant enzyme activity compared to cytoplasmic and wall-bound fractions. Polygalacturonase was determined as the first enzyme generated during the pathogenic process. These findings enhance our understanding of enzyme production dynamics in A. niger and offer insights for industrial and agricultural applications.