Study On The Chemical Constituents Of The Lipid-soluble Fraction Of The Fruit Of Lycium Barbarum L.

Lycium barbarum L.,a shrub of the Solanaceae family,is primarily distributed in Ningxia,Inner Mongolia,Gansu,Qinghai and Sinkiang of China.The fruit of Lycium barbarum L.(wolfberry),an important traditional Chinese medicine,has been used for invigorating liver and kidney.It also possesses of widely pharmacological effects,such as anti-oxidation,liver protection,eye protection,and prevention of cardiovascular diseases.The lipid-soluble fraction of wolfberry(LYBAE)showed significant anti-hepatic encephalopathy activity in the mice model,and the red constituents of wolfberry were distributed in this fraction.In order to reveal the global chemical profile of the lipid-soluble fraction and clarify the red constituents,the fraction LYBAE was studied.In this study,26 compounds were isolated from LYBAE using various chromatographic methods.Their structures were unambiguously determined by spectroscopic analyses(UV,IR,MS,and NMR)and chemical methods,including 3 carotenoids(1-3),4 triterpenoids(4-7),3 sterols(8-10),2 tocopherols(11 and 12),12 triglycerides(13-24),and 2 aliphatic hydrocarbons(25 and 26).Compound 1 was a new compound,and the 1D/2D NMR data of compound 2 was firstly reported.9 known compounds(2,12-14,16,17,19,20 and 23)were first obtained from the genus Lycium.According to the review,polysaccharides,dicaffeoylspermidine derivatives,polyphenols,and carotenoids were the four types of major constituents in wolfberry,and the predominant carotenoid is zeaxanthin dipalmitate(3).In this study,compounds 1 and 2 were another two major carotenoids in wolfberry after zeaxanthin dipalmitate(3).In addition,triglycerides were proved to be the fifth type of major constituents in wolfberry for the first time.In conclusion,this study revealed the chemical profile of the lipid-soluble fraction of wolfberry,which would contribute to clarifying the pharmacodynamic material basis of LYBAE against hepatic encephalopathy.Besides,this research found that zeaxanthin dipalmitate(3)and two zeaxanthin dipalmitate derivatives(1 and 2)are mainly responsible for wolfberry’s red color.