Rheological, functional and morphological characterization of reconstituted Aloe vera gels at different levels of pH and concentration: Novel concepts of reconstituted Aloe vera gels formation.

ABSTRACT

In this study, firstly, gelation process and its optimization at different pH (3-7) and concentration (0.2-1.6%, w/v) on the viscoelastic behavior of reconstituted Aloe vera (A. vera) samples were studied using response surface methodology (RSM). The optimum condition obtained by numerical optimization for the formulation of reconstituted samples was 1.6%, w/v at pH 7 with desirability of 0.84. Secondly, structural alteration of the reconstituted A. vera gels were evaluated using FTIR, SEM, and TEM at particular pH (3-7) and concentration (0.2-1.6%, w/v). The FTIR spectrum of reconstituted hydrogels showed formation of new hydrogen bond at 3600-3000 cm-1 and deacetylation of acemannan at 1740 cm-1 with increase in A. vera concentration. Moreover, SEM and TEM micrograph images of A. vera xerogel at lower concentrations (0.2-0.4%, w/v) evidenced the intact surface morphology and formation of clumps and at higher concentration (0.8-1.6%, w/v), exhibited rope-like network patterns and composed of spherical aggregates.