Extraction of raw plant materials using two-phase extractant systems containing suppository components

Abstract

It is suggested to use two-phase extractant (TPE) systems consisting of lipophilic and hydrophilic components of suppository bases for the extraction of biologically active substances from raw plant materials. The influence of the polar and nonpolar phases on the efficiency of extraction of lipophilic (chlorophylls) and hydrophilic (flavonoids, anthracene derivatives) biologically active substances has been studied using St. John’s wort (Hypericum perforatum) as a model medicinal plant. A TPE system comprising a mixture of A-type hard fat and 80% aqueous propylene glycol has been chosen for the extraction, and the optimum extraction conditions for St. John’s wort in this system have been established (temperature, 80 ± 5°C; extraction time, 90 min). Higher temperatures and longer periods of extraction lead to the decomposition of anthracene derivatives. The results obtained for several types of raw plant materials show that the yield of lipophilic compounds extracted using TPE systems is several times as large as that obtained by extraction with the hard fat component alone. It is also found that the major properties of the A-type hard fat, including the acid and peroxide numbers, melting point, solidification point, and hardness, are not influenced by heating and by the presence of a polar phase during two-phase extraction. A significant increase in the acid and peroxide numbers of the fat takes place upon its contact with the plant material. Thus, hard fat in a TPE system possesses a sufficiently high chemical and physical stability during the two-phase extraction process.