Studies on extraction of concrete from flowers of Sophora Japonica.L by supercritical carbon dioxide

摘要

The experimental research of the concrete extraction from flowers of Sophora Japonica. L. by means of supercritical carbon dioxide (SC-CO_2) as a solvent was studied. The apparatus with extractor volume in 1L was setup. Experiments were conducted at pressures between 10 MPa and 30 MPa and temperatures between 313K and 333K. The purity of carbon dioxide reached 99%. Flowers of Sophora Japonica.L, which were collected in May this year in Dalian, China, had fresh samples and dry samples. The experiments show that concrete can be extracted with supercritical carbon dioxide from fresh and dry flowers of Sophora Japonica.L. The concrete extracted were ropy yellow and had a strong odor of flowers of Sophora Japonica.L. The chemical composition of the extracts was primarily determined using GC-MS analysis methods. The major compounds of the essential oil were diethyl phthalate, rutinoside, isorhamnetin, hexadecenoic acid, tetradecadecenoic acid, quercetin, eicosanoic acid, hexadecanoic acid, octadecadienoic acid and so on. Experiments turned out that both the yield of concrete obtained from fresh flowers and that from dry flowers was nearly 1% (wt%). This article laid emphasis on improved methods of extraction process in order to increase the yield of concrete. Flowers of Sophora Japonica.L were dealt with by swelling with an alcohol solution of certain concentration (mass of solute: mass of solvent=1:3, at room temperature 20°C, 15min). The results showed that the yield obtained from flowers with swelling treated was more than 10 times than that obtained from flowers without swelling treated.