Method 1: a preparation method of high-purity salvianolic acid B:
a. First, pulverize the Chinese medicinal material Salvia miltiorrhiza. For the first time, add the crushed salvia miltiorrhiza under the condition of slight boiling of deionized water at 100 degrees for 1 hour, and use water 5 times the weight of Salvia miltiorrhiza; then under the condition of less than 50 degrees PH1-6.5 Extract 2-3 times, each time for 40 minutes, use 3 times the weight of Salvia miltiorrhiza water;
b. The extract is filtered and then chromatographed by macroporous adsorption resin, eluted with water, desorbed with 20—90% C1—C5 lower alcohol, and concentrated under reduced pressure to obtain salvianolic acid B the crude product;
c. The crude product of is further subjected to cellulose chromatography, eluted with lower alcohol or acetone, desorbed with water or lower alcohol of C1—C5, combined with the components containing salvianolic acid B, concentrated under reduced pressure, Freeze-drying to obtain high-purity salvianolic acid B.
d. In steps a, b and c, adjust the pH to 1-6.5 with a pH adjusting substance.
Method 2: a method for preparing high-purity salvianolic acid B by salting out, comprising the following steps:
(1) After crushing Salvia miltiorrhiza, extract it with alcohol solvent, water or alcohol-water mixture, filter and concentrate under reduced pressure to obtain a paste-like crude salvia miltiorrhiza extract;
(2) Simple purification treatment of the crude Salvia miltiorrhiza crude extract to obtain a crude crude extract; the purification treatment adopts precipitation, extraction, macroporous resin chromatography, forward chromatography or reverse chromatography; precipitation The method includes acid precipitation, water precipitation and alcohol precipitation. Water precipitation is to precipitate out water-insoluble low-polarity impurities, alcohol precipitation is to precipitate out alcohol-insoluble impurities, and acid precipitation is to precipitate out insoluble impurities under acidic conditions. Macroporous resins include weak polar and non-polar resins such as D101, AB-8, HPD-100, etc. Reversed-phase chromatography packings include reversed-phase silica gel and reversed-phase resins such as C18 silica gel, CG161, Sephadex LH-20, and the like.
(3) Dissolve the crude Salvia miltiorrhiza crude extract or the crude Salvianolic acid B crude extract in an organic solvent to obtain a crude solution of Salvianolic acid B, and add a salt-forming agent dropwise under slow stirring, and the pH of the salt-forming pH is 3-4 , the salt-forming temperature is 25-45 ° C, and the precipitated salvianolic acid B salt is precipitated; The weight percentage content of salvianolic acid B is 5～80%, and the molar weight of the salt-forming agent is 1-2.5 times of the molar weight of salvianolic acid B, and the salt-forming agent is a weak base solution and potassium, sodium, calcium, magnesium, ammonia, etc. , amine organic salt solution or potassium, sodium, calcium, magnesium, ammonia, amine carbonate solution; the organic solvent is selected from methanol, ethanol, propanol, acetone, acetonitrile, tetrahydrofuran, dioxane, dimethyl One or both of sulfoxide, formamide or ethyl acetate, preferably a mixed solution of ethyl acetate and absolute ethanol;
(4) Desalting salvianolic acid B salt by acid precipitation desalting method, extraction desalting method or macroporous resin chromatography desalting method, and drying to obtain high-purity .
