US 11,779,041 B2
Plant extraction method
Yuling Liu, Beijing (CN); Xiangyang Zhu, Beijing (CN); Yiqun Jin, Beijing (CN); Zhihua Liu, Beijing (CN); and Jundong Yang, Beijing (CN)
Assigned to BEIJING WEHAND-BIO PHARMACEUTICAL CO., LTD, Beijing (CN); and GUANGXI WEHAND-BIO PHARMACEUTICAL CO., LTD, Hechi (CN)
Appl. No. 17/638,011
Filed by BEIJING WEHAND-BIO PHARMACEUTICAL CO., LTD, Beijing (CN); and GUANGXI WEHAND-BIO PHARMACEUTICAL CO., LTD, Guangxi (CN)
PCT Filed Aug. 20, 2020, PCT No. PCT/CN2020/110179
§ 371(c)(1), (2) Date Feb. 24, 2022,
PCT Pub. No. WO2021/036896, PCT Pub. Date Mar. 4, 2021.
Claims priority of application No. 201910794907.2 (CN), filed on Aug. 27, 2019.
Prior Publication US 2022/0273014 A1, Sep. 1, 2022
Int. Cl. A61K 36/60 (2006.01); A23L 33/105 (2016.01); A61P 3/06 (2006.01); A61P 3/10 (2006.01); A61P 1/00 (2006.01); A61K 36/34 (2006.01); A61K 36/896 (2006.01)
CPC A23L 33/105 (2016.08) [A61K 36/34 (2013.01); A61K 36/60 (2013.01); A61K 36/896 (2013.01); A61P 1/00 (2018.01); A61P 3/06 (2018.01); A61P 3/10 (2018.01); A61K 2236/51 (2013.01); A61K 2236/55 (2013.01)] 15 Claims
 
1. A plant extraction method comprising the following steps of:
step 1): preparing a crude plant extraction solution by using a plant raw material; and concentrating the crude plant extraction solution;
step 2): separating the concentrated crude extraction solution via a cation resin and an anion resin to obtain a collection solution; wherein:
the cation resin is one or a combination of more selected from a strongly acidic cation exchange resin, a weakly acidic cation exchange resin, and a strongly alkaline quaternary ammonium-type cation resin;
the amount of the cation resin used and the plant raw material have a weight ratio ranging from 1:1 to 1:30;
an eluent for the cation resin is a salt solution containing cations or an alkaline solution containing cations; and the cations in the eluent have a concentration ranging from 0.04 to 5 mol/L;
collection from the cation resin begins when the pH of the effluent is higher than 7 or the starting point of the collection of the effluent is determined according to properties of components to be separated as determined by utilizing a precipitation reaction; and the collection from the cation resin is terminated when the volume of the collection solution reaches 0.1 to 10 times the weight of the plant raw material;
a weight of the eluent used for the separation via the cation resin is 0.1 to 30 times the weight of the plant raw material;
the anion resin is one or a combination of more selected from a strongly alkaline anion exchange resin, a weakly alkaline anion exchange resin, and a weakly acidic anion exchange resin; and
the amount of the anion resin used and the plant raw material have a weight ratio ranging from 1:1 to 1:80;
collection from the anion resin is terminated when the volume of the collection solution reaches 0.05 to 10 times the weight of the plant raw material;
step 3): concentrating the collection solution obtained in step 2);
step 4): subjecting the concentrated solution obtained in step 3) to alcohol precipitation using ethanol as the alcohol, wherein the ethanol used for the alcohol precipitation and the plant raw material have a weight ratio ranging from 1:4 to 1:600; and
optionally, step 5): concentrating and drying,
wherein
the plant is a branch of a plant of the genus Morus;
a plant extract obtained by the plant extraction method contains each component in the following weight ratios with respect to a total weight of the plant extract: alkaloids 30% to 99%; polysaccharides 0.2% to 35%; flavones 0.05% to 2%; amino acids 0% to 25%; and other components 0% to 20%;
the alkaloids in the plant extract contain 1-deoxynojirimycin with a weight content of 50% to 99% with respect to a total weight of the alkaloids, and
the heavy metal content of the plant extract is not more than 10 ppm.