US 11,911,433 B2
Preparation method of non-ester tea polyphenols rich in EGC
Xueyin Ren, Jiangyin (CN); Jianhong Liu, Jiangyin (CN); Houjian Cao, Jiangyin (CN); Pingnan Pu, Jiangyin (CN); and Dehe Liu, Jiangyin (CN)
Assigned to JIANGSU DEHE BIOTECHNOLOGY CO., LTD., Jiangyin (CN)
Appl. No. 18/024,758
Filed by JIANGSU DEHE BIOTECHNOLOGY CO., LTD., Jiangyin (CN)
PCT Filed Jan. 17, 2022, PCT No. PCT/CN2022/072230
§ 371(c)(1), (2) Date Mar. 4, 2023,
PCT Pub. No. WO2022/156615, PCT Pub. Date Jul. 28, 2022.
Claims priority of application No. 202110065862.2 (CN), filed on Jan. 19, 2021.
Prior Publication US 2023/0241151 A1, Aug. 3, 2023
Int. Cl. A61K 36/82 (2006.01); A61K 31/353 (2006.01); A61K 36/00 (2006.01)
CPC A61K 36/82 (2013.01) [A61K 31/353 (2013.01); A61K 2236/15 (2013.01); A61K 2236/31 (2013.01); A61K 2236/331 (2013.01); A61K 2236/39 (2013.01); A61K 2236/51 (2013.01); A61K 2236/53 (2013.01)] 8 Claims
 
1. A preparation method of non-ester tea polyphenols rich in epigallocatechin (EGC), characterized by comprising the steps of:
(1) pretreatment of tea leaves: using green tea leaves as raw materials, crushing and wall-breaking the tea leaves to obtain tea particles;
(2) endogenous enzymes enzymolysis: adding the pre-treated tea particles into a dynamic extraction tank, adding deionized water, and adding a food-grade acid to adjust the pH to 2.0-6.5; and under stirring conditions, performing enzymolysis on the ester tea polyphenols in the pre-treated tea particles by the hydrolytic enzymes of the tea itself;
(3) leaching: leaching the pre-treated tea particles after polyphenols with deionized water twice, filtering after each leaching, and combining the two filtrates;
(4) filtration: cooling the above-mentioned filtrate, filtering again, and collecting the filtrate;
(5) concentration: concentrating the filtrate in step (4);
(6) mobile extraction-water washing: extracting the concentrated solution in step (5) with 1-2 times volume of ethyl acetate, collecting an ethyl acetate phase, and concentrating the ethyl acetate phase to a solid content of 2-10%; then performing reverse phase extraction with 0.2-1 times volume of deionized water on the concentrated ethyl acetate phase, collecting a water-washed phase, and performing reverse phase extraction with the same method for 1-5 times, and combining the water-washed phases; and then performing extraction with 1-2 times volume of ethyl acetate for the water-washed phase, and collecting the ethyl acetate phase;
(7) conversion and dissolving: concentrating the ethyl acetate phase finally collected in step (6) to an extractum, and then adding deionized water for dissolution to obtain a tea polyphenol aqueous solution; and
(8) concentration: concentrating the aqueous tea polyphenol solution in step (7) under vacuum;
(9) drying: drying the concentrated solution in step (8) by spray drying to obtain a non-ester tea polyphenol product rich in EGC.