Cellulose isolated from Delonixregia pods: Characterisation and application in the encapsulation of vitamin A

Abstract

Native cellulose (NC) was extracted from agricultural waste (flamboyant fruit pods) using acidified sodium sulphite treatment followed by mercerization with sodium hydroxide. Carboxyl methyl cellulose (CMC) and cellulose acetate (CA) derivatives were obtained via etherification and acetylation of NC respectively under acidic conditions. Chemical composition, structural crystallinity, morphology, thermal studies, degree of substitution and acetylation of modified cellulose were reported. Wide angle X-ray diffractometry showed remarkable reduction in structural crystallinity and increased amorphous character upon modificationof NC.Scanning Electron Microscopy (SEM) displayed irregular spherical morphology and rough spongy-like mass for native and modified cellulose respectively confirming the surface disruption upon acetylation and carboxylmethylation. Proximate analysis revealed a reduction in the ash and fat contents of modified cellulose. Thermal analysis showed improved stability upon chemical modification of the NC. CMC significantly enhanced the stability of vegetable oil-water emulsion and ensured successful encapsulation of vitamin A in oil phase.