Isolation of β-mannanase from Cocos nucifera Linn haustorium and its application in the depolymerization of β-(1,4)-linked d-mannans

Abstract

β-Mannanase was extracted from coconut (Cocos nucifera Linn) haustorium and purified through ammonium sulfate precipitation and sepharose 6B–lectin affinity chromatography. Coconut β-mannanase is an acidic protein with a pI of 3.75. The molecular mass of coconut β-mannanase (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) was found to be 44 kDa and was confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The optimum temperature and pH for enzyme activity was 70°C and 5.2. The enzyme was used for the preparation of neutraceutical dietary supplement from galactomannans of guar gum and tender coconut kernel having a β-(1,4)-linked d-mannose backbone. Depolymerized guar gum has 92% of oligosaccharides with a degree of polymerization of 3 and 7. Tender coconut kernel has a degree of polymerization of 9–39 oligosaccharides along with disaccharides and trisaccharides. Hence this mannanase will be useful to depolymerize β-(1,4)-linked d-mannose polysaccharides from most plant sources to produce prebiotics in a cost-effective technique.

Keywords::

• Galactomannan
• β-mannanase
• haustorium
• Cocos nucifera Linn
• prebiotic

Acknowledgements

The authors are grateful to the Director, National Institute for Interdisciplinary Science and Technology (NIIST, CSIR), Trivandrum, India for providing the necessary facilities for the work.