Methods of extraction of plant materials and extracts obtained using supercritical glycerin

A method for extracting selected bioactive compounds from plant materials comprising contacting selected bioactive compound-containing plant materials soluble in supercritical glycerin, with a supercritical mixture of glycerin and one or more non-reactive inert gas co-solvents with an effective supercritical point temperature below 301° Kelvin to provide optimal concentrations of glycerin in the extract while reducing the supercritical point of the mixture, at temperatures between approximately 550° K and approximately 700° K and at pressures between approximately 250 kPa and approximately 7500 kPa, in an amount effective to maintain the glycerin in supercritical phase for a sufficient time to extract the selected bioactive materials from the plant materials, wherein the one or more inert co-solvents lower the effective supercritical temperature of the supercritical mixture to its boiling point for a time effective to produce a glycerin extract containing the selected bioactive compounds.