Studies On Extraction, Isolation And Purification Of Solanesol From Discarded Tobacco Leaves

Solanesol is an all-trans-polyprenol which can be used as a synthetic precursorfor coenzyme Q₁₀ and antitumor durgs.It was first isolated from flue-cured tobacco byRoland et al in 1956, the most abundant know source being tobacco and potatoleaves.the research on extraction, isolation, purification of solanesol from discardedtobacco leaves. We aimed to get the solanesol which conent is 90%,At the end of theresearch the conent of the solanesol is 60%. The works are summarized sevenaspects as follows.1. The research on extraction, isolation,purification,determination advances ofsolanesol from tobacco leaves was summarized.2. Solanesol was extracted, isolated, purified from discarded tobacco leaves,itpurity conformed to the demand of＜The provisions for new drug approval＞.Crudesolanesol was extracted from discarded tobacco leaves with Supercritical fluidextraction,then was saponified with NaOH, after freeze and recrystallization,thecrude solanesol was subjected to column chromatography on silica G.We have gotfour compounds, three of them was identified by ¹HNMR、¹³CNMR、DEPT.theyare n-docosanol、solanesol, n—tricosanoic acid..3. Solanesol were determined by RP-HPLC, The method is as follows: the columnwas packed with Lichrospher C₁₈ （4.6mm×250mm, 5μm）, the mobile phase consistedof methanol-isopropanol （50:50）, detected at wavelength 210nm while the columntemperature was 25℃. and the flow rate was 0.8ml·min^-1, The method was accurateand quick, The average recovery of solanesol was 99.36% with RSD of 2.43%.thin-layer chromatography method for discrimination of solanesol was established.The methods can be used both qualitatively and quantitatively as standards forquality control of solanesol.4. Optimal extraction conditions were obtained, it was investigated that use ofsupercritical carbon dioxide fluid extraction process and organic solvents extractionprocess for the extraction of solanesol from discarded tobacco leaves, supercriticalcarbon dioxide fluid had no superiority.In extraction section, methanol, alcohol,acetone,n-hexane,petroleum ether, chloroform,acetic ether were used as extractingagent with circumfluence extraction,we find that acetone and petroleum have thesuperiority on extraction percentage and extract purity.soxhlet extractiong showedadvantage over the circumfluence extraction, Using solanesol extraction percentage and extract yield as a marker, by orthogonal optimize design,the best is with 24 timespetroleum ether （one 10 times, two 8 times, three 6 times）, cricumfluence with 2hours （one 1 hour,two 0.5 hour, three 0.5）.soaking in 4 times petroleum ether,thegrade size is 20.5. Saponification of crude extracts were obtained,we have got the best conditions,the time is 2 hours, Temperature was 50℃,and the NaOH was 6%,the volume ofalcohol was 20ml per gram crude, the conent of solanesol we have got is 30%.6. we have got a good result by using adsorption resin isolation and purification ofsolanesol.Studied the factors of adsorption resin, such as the adsorptive and elutionratio,we knew that AB-8 was much better. by orthogonal experiment design of formL₉ （3⁴）, the three factors were concerned in this experiment, The concentration of thesample was 3.1mg/ml, the ratio of diameter and height was 1: 9,Adsorption velocitywas 1BV/h,Temperature was 25℃, we have got most of the solanesol from adsorptionresin by eluting with acetone and alcohol(（0: 1, 1: 9, 2: 8,v/v） in turn. At the endof the research the conent of the solanesol is 60%.7. To study the technical process to extract solanesol in potato leaves by ultrasonicextraction. The optimal conditions of ultrasonic extraction method was:solvent wasmethol,extraction power:300W, extraction time:20min, rate of solvent to material is30:1 （v/w）.