Production of manno-oligosaccharides from locust bean gum using immobilized Penicillium occitanis mannanase

Mannanase was immobilized on chitin with glutaraldehyde by cross-linking reaction. The immobilization conditions and the characterization of immobilized enzyme were carried out. The immobilization yield and the mannanase activity recovery were 94.81% and 72.17%, respectively. The optimal mannanase activity shifted to lower pH after immobilization. However, the optimum temperature remained unchanged at 70 degrees C. The immobilized enzyme exhibited better thermal and pH stability than the free one. It also exhibited a high storage stability and retained 70% of its initial activity after 120 days. The main hydrolysis products yielded from locust bean gum were mannotriose and mannotetraose. The resulting manno-oligosaccharides could be used as a special nutrient for lactic bacteria. (C) 2011 Elsevier B.V. All rights reserved.