Degradation of arabinans by arabinanases from Aspergillus aculeatus and Aspergillus niger

• Published in: Carbohydrate polymers 1993, Vol.20 (3), p.159-168
• Main Authors: Beldman, G., Searle-van Leeuwen, M.J.F., De Ruiter, G.A., Siliha, H.A., Voragen, A.G.J.
• Format: Article
• Language: English
• Subjects: antibodies; Applied sciences; arabinofuranosidase b; arabinose; Aspergillus aculeatus; Aspergillus niger; Biological and medical sciences; Biotechnology; endo-arabinasase; enzyme activity; Enzyme engineering; Exact sciences and technology; Food Chemistry and Microbiology; Fundamental and applied biological sciences. Psychology; glycosidases; glycosidic linkages; Improved methods for extraction and purification of enzymes; Levensmiddelenchemie en -microbiologie; Methods. Procedures. Technologies; Natural polymers; Physicochemistry of polymers; purification; stability; Starch and polysaccharides
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/0144-8617(93)90146-U

An endo-arabinanase was purified from an enzyme preparation, derived from Aspergillus aculeatus. After SDS-gel electrophoresis a molecular weight of 45 kDa was estimated. The enzyme was reactive with antibodies raised against endo-arabinanase from Aspergillus niger, having the same molecular weight. Besides similarities, remarkable differences were observed for endo-arabinanases from A. niger and A. aculeatus. The enzyme from A. aculeatus was optimally active at a higher pH and produced a different spectrum of oligomers after incubation with linear arabinan. This was reflected in a relatively low concentration of oligomers with a degree of polymerization (DP) of 13 and a high concentration of oligomers with a DP of 6–7. Contrary to this, the concentration of oligomers produced by the A. niger endo-arabinanase gradually increased, going from DP 20 to DP 3. Both endo-arabinanases, as well as arabinofuranosidase B from A. niger, were studied with respect to the degradation of branched arabinans. Removal of arabinofuranosyl side chains by arabinofuranosidase B was essentially independent of the type of glycosidic linkage but had a tremendous effect on the digestibility by endo-arabinanase.