Chitosan-alginate matrices loaded with leaf extracts of Anredera cordifolia Steenis as a gastrointestinal extended-release formulation

The development of chitosan-alginate matrices loaded with Anredera cordifolia Steenis (Madeira-vine) leaf extract as an extended-release formulation is herewith described. Madeira-vine plants have been known used traditionally to treat various ailments such as anti-inflammation, hypertension, and skin diseases. The matrices were prepared using the ionotropic gelation methodwith tripolyphosphate as the cross-linking agent. Scanning electron microscope and Fourier transform infrared spectroscopy was used to investigate the surface morphology and the structure of the matrices, respectively. The effect of alginate addition was studied by determining the physical characteristics of the matrices, encapsulation efficiency, loading capacity, matrix yield, as well as the release profiles of the bioactive compounds in simulated gastrointestinal fluids. The bioactive compounds in the leaf extracts and matrices, quantified as total phenolics, were determined using UV-spectrophotometry. High-performance liquid chromatography was used to determine the amount of vitexin present in the leaf extracts. The encapsulation efficiency of the phenolic compounds was at least 90%, the highest loading capacity was 1.23%, and matrix yield was at least 83%. The in vitro release assays showed a reduced cumulative release of phenolic compounds in synthetic gastric fluid (35 to 12%), and, in three synthetic gastrointestinal fluids (71 to 50%) after 24 hours, due to the addition of alginate in the chitosan matrix. These results indicate the possibility of employing chitosan-alginate matrixto shift the release of phenolics of Anredera cordifolia extracts from the gastric area to the colon area.The development of chitosan-alginate matrices loaded with Anredera cordifolia Steenis (Madeira-vine) leaf extract as an extended-release formulation is herewith described. Madeira-vine plants have been known used traditionally to treat various ailments such as anti-inflammation, hypertension, and skin diseases. The matrices were prepared using the ionotropic gelation methodwith tripolyphosphate as the cross-linking agent. Scanning electron microscope and Fourier transform infrared spectroscopy was used to investigate the surface morphology and the structure of the matrices, respectively. The effect of alginate addition was studied by determining the physical characteristics of the matrices, encapsulation efficiency, loading capacity, matrix yield, as well as the release profiles of the bioactive compounds in simulated gastrointestinal fluids. The bioactive compounds in the leaf extracts and matrices, quantified as total phenolics, were determined using UV-spectrophotometry. High-performance liquid chromat...