| On account of the outbreak of avian influenza around the world in 2005, star anise fruit used as the Chinese traditional spice has been paid more attention to because it contains an important component, shikimic acid, which was used as a raw material for producing drug for inhibition of avian influenza virus. And it turned to be another component of a specific drug coped with A/H1N1 influenza. Through inquiry and collate information, the paper do research on shikimic acid on plant resources for a tentative exploration, on the way of separation and purification of shikimic acid which was extracted from traditional extraction plant star anise and new resources Liquidambar leaves. The test was expected to provide a reference for the exploration and utilization of plant resources of shikimic acid.The test explored the extraction conditions through star anise and cedar. The results showed that different materials had different extraction conditions. For the extraction of star anise, the solvent affected it most, then the solid-liquid ratio and time subsequently. Its optimum conditions were solvent (water), solid-liquid ratio (1:15), time (120 minutes). Well, for cedar, the order of those three facters was: solvent, time, solid-liquid ratio. Its optimum conditions were solvent (95% ethanol), time (120 minutes), solid-liquid ratio (1:15).By comparing different plant resources, it turned out that, under the same extraction method, Liquidambar leaves (5.16%) and Ginkgo leaves (4.13%) had almost the same amount of shikimic acid as Star anise (4.06%) did. So, Liquidambar leaves and Ginkgo leaves might be supplementions and replacements of Star anise in production. Test results also showed activated carbon's good adsorbability to shikimic acid.In purifying shikimic acid with single resin, macroporous resins HLD-16 (71.80%) showed the best purification effect, then macroporous strongly alkali styrene type I anion exchange resin D201 (64.58%), macroporous resins H103 (53.75%), macroporous weakly alkali styrene type anion exchange resin D301 (51.30%) and 201×7 (717) weakly alkali styrene type anion exchange resin (44.69%) subsequently. Data showed that it was hard to obtain shikimic acid of higher purity with only one resin.In purifying shikimic acid with double resins, extractions were first purified in macroporous resins, then in ion exchange resin. Results showed:extractions of star anise and Liquidambar leaves had the same elution condition(for H103,eluting with 35% ethanol, discarding the first 20ml, collecting the later 460ml; for HLD-16, eluting with 35% alcohol, discarding the first 40ml and collecting the later 330ml.). Test data showed:with macroporous, the purity of shikimic acid in Liquidambar leaves was increased, as well as the yield and recovery (up to 90%). Thus, the method of first purification of shikimic acid extractions by macroporous resin is feasible. In further purificition test with ion exchange resins, the eluting condition of star anise with 201 x 7 resin was eluting by 1mol/1 hydrochloric acid, discarding the first 300ml and collecting the later 370ml; with D301, discarding the first 350ml and collecting the later 300ml. The eluting condition of Liquidambar leaves with 201 x 7 resin was discarding the first 350ml and collecting the later 320ml; with D301, discarding the first 360ml and collecting the later 290ml. However, after the ion exchange resin purification, the yield and recovery of shikimic acid in Liquidambar leaves were relatively low, and purity was not very high(purity up to 65.41%).In this study, ginkgo and liquidambar leaves were explored. With their high amount of shikimic acid, they might be used as a supplementation of star anise. Purification conditions of several different resins were explored. This study was expected to provide a reference for the exploration and purification methods of plant resources of shikimic acid, help for the production practice. |
