| 摘要 |
A method for extracting and separating ginkgolides. The ginkgolides obtained through steps of extraction on a ginkgo leaf, further extraction, column chromatography, crystallization, and crystal mixing comprise 25.0% to 50.0% of bilobalide (C15H18O8), 20.0% to 45.0% of ginkgolide A (C20H24O9), 10.0% to 30.0% of ginkgolide B (C20H24O10), and 5.0% to 15.0% of ginkgolide C (C20H24O11). The total quantity of the bilobalide, the ginkgolide A, the ginkgolide B, and the ginkgolide C is over 95%. |
| 主权项 |
1. A method for extracting and separating ginkgolides, comprising:
A. extracting:
crushing ginkgo leaves, adding an organic solvent for extraction to produce an extracted solution,concentrating the extracted solution to produce a concentrated extracted solution,adding an anti-oxidization protection agent to the concentrated extracted solution, adjusting a pH to 4 to 5 with a pH adjusting agent, which is followed by concentrating and refrigerating to form a refrigerated concentrated solution; wherein in the step A, the organic solvent for extraction is ethanol, acetone, or ethyl acetate, with a concentration of 50 to 80% v/v and an amount in liters that is in a range of from 5 to 12 times a number equal to a mass in kilograms of the ginkgo leaves; B. further extracting:
extracting the refrigerated concentrated solution 2 to 3 times with n-hexane or petroleum ether firstly to produce a first aqueous phase and a first organic extracting phase,extracting the first aqueous phase 4 to 5 times with a lipid-soluble solvent to produce a second aqueous phase and a second organic extracting phase,extracting the second aqueous phase 4 to 5 times with a water saturated sec-butyl alcohol-ethyl acetate mixed solvent or water saturated n-butyl-ethyl acetate mixed solvent to produce a third aqueous phase and a third organic extracting phase,combining the second and the third organic phase extracted solutions, and concentrating under reduced pressure to produce a extracted concentrated solution; C. passing through a column:
passing the extracted concentrated solution through a polyamide resin column, sequentially eluting with 15 BV of water, 3 to 5 BV of 20% to 40% v/v ethanol and 2 to 3 BV of 60% to 90% v/v ethanol, controlling a flow velocity of an eluant to 2 to 3 BV/h;concentrating the eluant under reduced pressure, and drying to produce a dry substance; D. separating crystals out:
adding the dry substance to boiling water, dissolving by agitating, cooling, extracting a supernate 4 to 5 times with ethyl acetate, ethyl formate or acetone in a volume equal to that of the supernate, combining extracted solutions, concentrating under reduced pressure, drying by distillation, adding an amount of 30% to 50% v/v ethanol in liters that in a range of from 5 to 8 times a number equal to a mass in kilograms of the dried substance, dissolving by heating and agitating, filtering, refrigerating, separating crystals out, filtering to obtain a filtrate I for later use, washing the crystals with 30% to 50% v/v ethanol, and drying under reduced pressure to obtain crystals I;concentrating the filtrate I until the alcohol content is 10 to 30% v/v, refrigerating, separating crystals out, filtering to obtain a filtrate II for later use; and washing with 30 to 50% v/v ethanol, and drying under reduced pressure to obtain crystals II;concentrating the filtrate II, adding 0.1% to 0.5% active carbon for adsorption, filtering to obtain a filtrate, concentrating the filtrate until the alcohol content is 10% to 30% v/v, refrigerating, separating crystals out, filtering to obtain a filtrate III for later use, washing the crystals with 30% to 50% v/v ethanol, and drying under reduced pressure to obtain crystals III;concentrating the filtrate III, passing through an active-carbon-silica gel column, eluting with 30% to 50% v/v ethanol firstly, then eluting with 70% to 90% v/v ethanol, collecting eluants, concentrating until the alcohol content is 10% to 30% v/v, refrigerating and separating crystals out, filtering the crystals out to obtain a filtrate IV for later use; and washing the crystals with 30% ethanol, and drying under reduced pressure to obtain crystals IV;concentrating the filtrate IV, refrigerating, separating crystals out, filtering, washing the crystals with 30% v/v ethanol, and drying under reduced pressure to obtain crystals V; and E. mixing the crystals:
uniformly mixing the crystals I, II, III, IV and V, and crushing to obtain the ginkgolides. |
