Studies On Chemical Constituents From Bletilla Striata And Their Biological Activities

Bletilla striata（Thunb.）Reichb.f.,a medicinal plant,is a perennial herb belonging to Bletilla Reichb f.（family Orchidaceae）.It contains bibenzyls,phenanthrenes,phenanthraquinones,triterpenoids and its saponins and other components.This herb has many functions such as wound healing,hematemesis,hemoptysis,traumatic bleeding,chapped kin,and ulcerative carbuncle.Recently,the biological activities,including hemostasis,antimicrobial,anti-inflammation,anti-ulcer,anti-tumor,anti-oxidation,immune-modulatio,have been reported by domestic and foreign researchers.In order to further clarify its pharmacological substance basis and screen its monomers with better anti-tumor and anti-inflammatory activities,this research systematically studied the chemical composition of Bletilla striata from Yunnan province and carried out related biological activity research based on the characteristics of the isolated compounds.1.In this paper,the 95%ethanol extracts of Bletilla striata tubers was extracted with petroleum ether,ethyl acetate and n-butanol respectively.Silica gel column chromatography,reversed-phase C18 open column chromatography,semi preparative HPLC and other separation methods were applied to systematically separate and purify the extractive ethyl acetate parts of Bletilla striata tubers,which yielded 30 compounds in total.We identified 30 compounds,by analyzing the UV,MS and 1D,2D-NMR spectra,which yielded 1 new compound and 29 known compounds,including three 9,10-dihydrophenanthropyran derivatives compounds,bletilore A（1^*）、bletilol A（2）、bletilol B（3）;three biphenanthrenes compounds,blestrianol A（4）、gymconopin C（5）、blesriarene A（6）;two9,10-dihydrophenanthrenes derivatives compounds,2,7-dihydroxy-1-（p-hydroxybenzoyl）-4-methoxy-9,10-dihydrophenanthrene（7）、1-（p-hydroxybenzyl）-4-methoxy-9,10-dihydrophenanthrene-2,7-diol.（8）;four9,10-dihydrophenanthrenes compounds,2,7-dihydroxy-4-methoxy-9,10-dihydrophenanthrene（9）、2-hydroxy-4,7-dimethoxy-9,10-dihydrophenanth-rene（10）、2-methoxy-9,10-dihydrophenanthrene-4,5-diol.（11）、4-methoxy-9,10-dihydrophenanthrene-1,2,7-triol.（12）;three simple phenanthrene compounds,1,5-dimethoxy-2,7-phenanthrenediol.（13）、5-methoxyphenan-threne-2,7-diol.（14）、epheranthol（15）;six complex monobenzyl bibenzyls compounds,3,3′-dihydroxy-2′-（p-hydroxybenzyl）-5′-methoxybibenzyl（16）、gymconopin D（17）、3′-hydroxy-4′-（p-hydroxybenzyl）-3,5′-dimethoxybibenzyl（18）、bulbocol（19）、arundinan（20）、3′-hydroxy-6′-（p-hydroxybenzyl）-5′-methoxybibenzyl（21）;seven simple bibenzyls compounds,gigantol（22）、3,5,5′-trihydroxy-4′-methoxybibenzyl（23）、batatasinⅢ（24）、3-O-methyldihydropinosylvin（25）、dihydropinosylvin（26）、3,5,5′-trihydroxybibenzyl（27）、3,5,4′-trihydroxybibenzyl（28）;one alkaloid,indole-3-aldehyd（29）;one simple aromatic compound,p-hydroxybenzyl alcohol（30）.Among the above compounds,compound 1^*is a new 9,10-dihydrophenanthropyran derivatives compounds,and compounds 10-13,15,23,25-30（12 in total）were all isolated from Bletilla striata for the first time.2.Compounds 1-18,20-30 were assessedin terms of their cytotoxic effects against three human tumor cell lines（Hep G2,T98G and MCF-7）.The results showed that none of these compounds had significant antiproliferative activity.3.In order to evaluate and screen the anti-inflammatory activities of twenty-nine compounds（1-18,20-30）,the cytotoxicity was determined by CCK-8 method.RAW264.7 cells induced by LPS was used as inflammatory model.The production of NO in culture supernatant were measured by Griess method.The results showed that compounds 11（2-methoxy-9,10-dihydrophenanthrene-4,5-diol）,at 20μM,the inhibition rate of NO production was over than 50%,with IC₅₀values as 19.78±0.14μM and showed some anti-inflammatory activity.