Isolation,Identification And Bioactivity Of The Chemical Constituents From Leaves Of Tetraena Mongolica

The constituents or activity screening of lots of plants in China have not been reported.For example,the consitituents of many endermic plants of 500 species in 200 genera have not been studied or is not studied thorough enough.Tetraena Mongolica Maxim,which originated in the tropical floristic region of the Tethys Sea 70 million years ago and currently occurs only on the northwest Ordos plateau,is a species of Zygophyllaceae endemic to China.Some metabolites,oleanolane triterpenoides and flavanols,have been isolated from T.Mongolica.However,its characteristic secondary metabolites have not been reported,we therefore chose this plant to pursue our ongoing search for novel natural products with important bioactivities.Phytochemical investigation of the leaf extract of T.Mongolica,the structural elucidation of these compounds was performed using Q-TOF-MS,NMR,and experimental and calculated electronic circular dichroism?ECD?data.The content of isolated compounds were quantified in different season.The anti-cancer,anti-tyrosinase,anti-tyrosinase,and anti-CdCl₂ activities of isolated compounds were described.The expression of caspase 3,cleaved caspase 3,Bax,Bcl-2,beclin 1,and P62 in cells treaemtent with compounds and CdCl₂ were evaluated.It is important for further study on the metabolites and biological functions of the relict plant of T.Mongolica.The results are as follows:1.Phytochemical investigation of the leaf extract resulted in the isolation of 21 compounds,including 7 sesquiterpenes,8 phenols and 6 flavonoids.Compounds 2-7 are new compounds,compounds 1-8 have unusual O-sulfoglucosyl groups.2.The content of isolated compounds appeared rising and then decreasing trend from June to October.The content of compounds1,2,3,6,7,and 18 reached the highest in August,and the content of compounds 4,5,8,14,15,16,17,and 19 reached to the highest in June.3.The plausible biosynthetic pathways of sesquiterpenes from T. Mongolica were hypothesized,compounds 1-4,7,9 and 10 may be generated undergo dehydration,oxidized,glycosylated,sulfonated of abscisic acid or ionone formed by the product of glycolysis.4.All of the isolated compounds displayed weakly cytotoxicity, compounds 6,8,and 15 shown anti-tyrosinase,compounds 9 and11 shown anti-CdCl₂ in 293t cells,and compound 11 shown anti-CdCl₂ in L02 cells.5.The expression of cleaved-caspase 3,Bax,and beclin 1 were increased by treatment with CdCl₂,and the expression of Bcl-2were decreased by treatment with CdCl₂.However,the action was restored by combined treatment with compound 11,it shown that compound 11 attenuates cadmium-induced damage and apoptosis in 293t and L02 cells.