Study On The Extraction And Purification Of Solanesol From Waste Tobacco Leaf

Solanesol is one high value-added fine chemical mainly existing in the flue-cured tobacco, potato and mulberry leaves. It belongs to polyisoprene alcohol and displays strong ability to eliminate free radicals, excellent bioactivities such as anti-oxidation, anti-radiation, anti-inflammation, and fungicidal activity for its nine non-conjugated double bonds in the structure. It has been widely used in production of healthy products, cosmetics, anti-hypertension medicines, and anti-tumor drugs, with high market prospects.The manufacture process of solanesol from tobacco leaves comprises of extraction and purification. On the basis of literatures and prior studies, we investigated the contents of solanesol from ten species of tobacco leaves and waste tobacco leaves and drawed off one new technology to isolate solanesol from waste tobacco leaves.During the liquid-liquid extraction of solanesol from tobacco leaves with two immiscible solvents, solanesol, polar impurities, nonpolar impurities distributed in the different solvent phases because of their relatively different polarity and solubility, and thus made the phase separation easily and eliminated the viscidity of prior filtration. The experimental results proved that the solanesol content obtained by this method reached up to 20%～26%, 1.3-1.6 times that of prior arts, and the extraction rate reaches 6‰, much higher than those reported in the literatures.It effectively inhibited the oxidative degradation of solanesol in the acidic alcohol medium through introduction of reactive extraction technology which made the solanesol extracted into nonpolar solvent phase for its formation. This innovation process solved the viscous matters which produced in saponification in aqueous alcohol medium and consequently greatly simplified the phase separation. This technology would greatly improve the operation feasibility for large scale production and reduce the solanesol loss in operation. The solanesol content of non-saponified mass obtained by this method was high up to 30-40%.According to their relatively different polarity and solubility of solanesol, polar impurity and nonpolar impurity in different solvents, one solvent formulation has been designed to purify the non-saponified mass. Additional methods of solvents and process control were also studied to selectively eliminate specific impurity in the specific order. By this process, more than 90% solanesol products were obtained without tedious column chromatography operation, and hence enhanced the production efficiency and reduced the production cost. The experimental results showed that the total yield from extractum to 90% solanesol products could be 56%~64% by this novel process in this paper.The column chromatograph was used to purify the 90% solanesol to produce 98% solanesol products. The alumina was stationary phase and solvent mixture of n-hexane-ethyl acetate with 4:1 (v/v) was mobile phase.The products of pure solanesol got in the experiment were identified by IR, MS, and elemental analysis.