| i Eucommia ulmoides Olive., very abundant in our country, is a kind of deciduoustrees. Lignans in Eucommia ulmoides Olive. which have many pharmacological effects are a sort of important active ingredients. Ionic liquids, also called green solvents, have many advantages. So they have been increasingly applied to extraction of natural products. Ionic liquids were used to extract lignans from barks of Eucommia ulmoides Olive in this thesis. In addition, purification of pinoresinol diglucopyranoside and medioresinol diglucopyranoside were discussed. Details are as follows:(1) The detection method of lignans in Eucommia ulmoides Olive. was established.Lignans were developed with chromotropic acid, then the concentrations of them were detected by UV-Vis. With the wavelength being 525 nm, the standard curve equation was A = 0.0002 C + 0.0061( A- absorbance, C- concentration, μg·m L-1). R2was0.9995. The linear relationship ranged from 95.30 to 3050 μg·m L-1. The optimized HPLC method to detect pinoresinol diglucopyranoside and medioresinol diglucopyranoside simultaneously was: Dimamonsil C18 column(250 mm × 4.6 mm, 5 μm), V(methanol) : V(0.05% phosphoric acid) = 14:86 as the mobile phase, 227 nm as the detecting wavelength and the temparature was 25℃. Standard curve equation of pinoresinol diglucopyranoside was A = 0.0185 C + 0.0695(A- peak area/1000000 and C- concentration, μg·m L-1). R2 was 0.9993. The linear relationship ranged from 23.83 to 762.5 μg·m L-1. Standard curve equation of medioresinol diglucopyranoside was A =0.018C- 0.0144. R2 was 0.9995. The linear relationship ranged from 8.720 to 279.0μg·m L-1. Methodology results showed that the precision, reproducibility, stability and standard addition recovery rate of these methods were good. Under these conditions, the yields of total lignans, pinoresinol diglucopyranoside and medioresinol diglucopyranoside from barks of Eucommia ulmoides Olive. were 10.19%, 0.2251% and 0.08520%,respectively.(2) The technology of ionic liquids extraction of total lignans in Eucommia ulmoides Olive. was optimized. The suitable solvent that ionic liquid-based ultrasonicassisted method extracted the total lignans from barks of Eucommia ulmoides Olive.was [C4mim]BF4. The optimized condition of ionic liquids extraction were: 0.8677mol·L-1 of [C4mim]BF4, 18:1 m L·g-1 of liquid-solid ratio, 54℃ of ultrasonic temperature,30 minutes of extraction time and 2 h of soaking time only once. The yield of total lignans was 11.10%. However, the yield of total lignans extracted by ethanol ultrasonicassisted method was 7.436%. The yield extracted by ethanol hot reflux method was9.984%. Under these conditions, the yields of pinoresinol diglucopyranoside and medioresinol diglucopyranoside from barks of Eucommia ulmoides Olive. extracted by[C4mim]BF4 were 0.2316% and 0.08930%, respectively. So this proposed method wasrapid, efficient, simple and well reproductable.(3) The purification of lignans containing pinoresinol diglucopyranoside and medioresinol diglucopyranoside in Eucommia ulmoides Olive. was studied. AB-8 resin was screened to purify lignans. And it was used to investigate the adsorption isotherms,the adsorption curves, the breakthrough curves and the elution curves of pinoresinol diglucopyranoside and medioresinol diglucopyranoside. Then the extract of lignans from Eucommia ulmoides Olive. was obtained. The contents of pinoresinol diglucopyranoside and medioresinol diglucopyranoside in the extract were 9.313% and 8.034%,respectively. The positive phase silica gel column chromatography was applied to purification of the extract. Then the crudes of pinoresinol diglucopyranoside and medioresinol diglucopyranoside were separately obtained. Their purities were 58.69%and 47.31%, respectively. Finally, the semi-preparative HPLC method was separately used to purify the raws. And the products of pinoresinol diglucopyranoside and medioresinol diglucopyranoside were separately obtained. The purity of pinoresinol diglucopyranoside was 92.94% and the one of medioresinol diglucopyranoside was93.38%.(4) The structures of lignans containing pinoresinol diglucopyranoside and medioresinol diglucopyranoside obtained from experiments were characterized,respectively. |
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