Encapsulated drug system based on the gels obtained from callus cultures modified pectins.
The aims of this research were to obtain modified pectins of callus cultures using various culture conditions, to evaluate the relationship between the chemical characteristics of pectins, the swelling behavior and the release of prednisolone from calcium pectinate gel (CaPG) beads. An increase of the calcium concentration in the culture media correlated significantly with the rhamnogalacturonan I (RG-I) branching of the pectin. The beads from the pectin with a higher RG-I branching had the lower prednisolone release in a gastric fluid. The beads produced from the pectins obtained from callus cultured with a higher calcium concentration showed the lower prednisolone release. The swelling of the CaPG beads from pectin with a lower molecular weight (Mw) or linearity occurred to a lower degree. All beads prepared from modified pectins showed a high stability and a slow liberation of prednisolone in the simulated gastric and intestinal fluids, whereas rapid drug release in a colonic fluid. An applied strategy involving modification of the pectic structure using the abiotic factors allows obtaining the pectic gels with modified functional properties, in particular, with enhanced gastric and small intestinal resistance and a low drug release. These CaPG beads can be applied as the carriers for colon delivery of the drugs.