Isolation, characterization and formulation properties of a new plant gum obtained fromCissus refescence

This study elucidated the physical, thermal, sorption and functional properties of a gum obtained from the stem of Cissus refescence (CRG). Scanning electron microscopy (SEM), Particle size analysis, X-ray powder diffraction (XPRD), Thermo gravimetric analysis (TGA), Differential scanning colorimetry (DSC), Fourier transmittance infra red (FTIR), and Elemental analysis were used to characterize the gum sample. Tablets were prepared by incorporating an anti asthmatic drug; theophylline. In vitro drug release was  carried out in simulated gastric and intestinal conditions. Effect of gum concentration on release kinetics was evaluated. CRG had a glass transition (Tg) and melting peak of 233.5 and 270o C respectively. This material showed a 10.59 % loss in weight at 195o C. The sample had very strong peaks at approximately 14o, 15o, 23o, 24o, and 29o2θ degrees of 2-theta (θ) in the X-Ray Powder Diffraction pattern. Elemental analysis showed that CRG contains 44.1, 7.1, 48.5, and 0.3% Carbon, Hydrogen, Oxygen and Nitrogen respectively. Release of theophylline under simulated biologic conditions varied between 2 to 12 hours depending on the concentration of the gum used in formulation. Drug release was found to be erosion-controlled initially (i.e. in SGF), but at later stage, it became swelling -controlled (i.e. in SIF). The results obtained in this study establish the fundamental characteristics of CRG. The matrices were pH sensitive and can potentially be used for intestinal drug delivery.