EN
All Categories

Home>News>Healthy Care


How does the luteinester convert to lutein?

Date:2019-09-30

Abstract: In this paper,extraction of  lutein ester with n-hexane from marigold with methanol treatment and the  best conditional for Lutein ester saponification by the orthogonal  experiments of L 9(34),  It is found that using 20% KOH methanol as the extracting solution,  with saponification reaction time of 40 minutes, at a temperature of 50  ℃, Lutein ester can be thoroughly saponified. Lutein can then be  recrystallized in the solvent of acetone and methanol is (1∶1). The  purity of lutein crystal is 97.2%.

Marigold ( Tagetes  erecta L. ) is a perennial herb of the genus Asteraceae, which yellow  pigment formed eater is mainly lutein and an ester of saturated fatty  acids such as lauric acid,myristic acid, palmitic acid. The free lutein  can be directly absorbed and used by the body and the content is very  low and Lutein ester is absorbed must be hydrolyzed to lutein in the  body. Lutein is an oxygenated carotenoid whose molecular structure  consists of a central polyene chain and an aromatic ring on both sides,  and there is a hydroxyl group (-OH) on each aromatic ring. In many  natural resources (such as in the petals of higher plants). Lutein  exists in the form of ester and most of lutein and its esters present in  nature are all-trans isomers. 


Extraction of lutein ester  

Technology procedure:  

Marigold flower→Methanol extraction→residue→N-hexyl extraction→Extract concentration→Crude extract of Lutein ester  

Saponification of Lutein ester and purification of Lutein  

Crude extract of Lutein ester→Add KOH/Methanol mixed solution soap→Acetic acid neutralization excess KOH→Filter→Soap matter


Lutein purification  

The saponified product mainly contains  lutein, fatty acid potassium soap and potassium acetate etc,  the  saponified product is dissolved in acetone to remove the soap, and the  obtained filtrate is evaporated to dryness and then crystallized from methanol.  


At present, the raw  material for natural lutein is mainly marigold, It can be obtained by  saponification of lutein ester, which is the major extracts from  Marigold. Lutein is widely used in food, food additive, drugs, and feed  industries. Preparation techniques of natural lutein include flower  fermentation, dry granulation, extraction of flavin ester,  saponification of Flavin ester, purification of Flavin, etc. In this  paper, Without passing through fermentation and granulation. Extraction  of lutein ester with n-hexane from marigold with methanol treatment and  the best conditional for Lutein ester saponification by the orthogonal  experiments, satisfactory results have been obtained.