Immobilization of Aspergillus quadrilineatus RSNK-1 multi-enzymatic system for fruit juice treatment and mannooligosaccharide generation

Aspergillus quadrilineatus RSNK-1 produced a multi-enzymatic system containing (U/gds) beta-mannanase (1021), endo-xylanase (1 9 1), alpha-galactosidase (3.42), beta-xylosidase (0.07) and beta-glucosidase (0.28) on low-cost copra meal (CM) in SSF. The enzyme preparation was covalently immobilized on aluminum oxide pellets (3 mm) under statistically optimized conditions leading to 73.17% immobilization yield. The immobilized enzyme (Man-AOP) displayed enhanced thermal and pH stability. Man-AOP was characterized by FTIR, SEM and PXRD revealing a covalent interaction. The bio-conjugate was successfully recycled for mannooligosaccharide (MOS) generation from locust bean gum (LBG) up to 10 cycles, yielding an average of 0.95 mg MOS/cycle. Man-AOP was also effective in clarification of apple, kiwi, orange and peach juices and enhanced their reducing sugar content. The bio-conjugate was useful in generation of MOS from mannan and enrichment of fruit juices.