Study On The Transformation Of Rat Liver Microsomes With Chemical Components Of Trollius

Flos Trollii is the dried flower of Trollius chinensis Bunge(Ranunculaceae)that mainly contains flavonoids,phenolic acids and alkaloids compounds.The contribution of these three kinds of compounds to the flowers of T.chinensis is controversial.To determine the effective constituents of the flowers of T.chinensis needs to overall consider the active intensity and metabolism in body.The liver is the main organ for drug metabolism.CYP450 enzyme is the main enzyme in liver for drug metabolism.At present,Liver microsome which contains CYP450 enzyme has been widely used in hepatic metabolism study in vitro.The flowers of T.chinensis were extracted with boiling water to prepare the extract and individual compounds.Model of rat liver microsomal transformation in vitro was established,and the extract and representative compounds of flavonoids,phenolic acids and alkaloids of these flowers,i.e.veratric acid,trollioside,proglobeflowery acid,vitexin,orientin,2?-O-?-L-galactopyranosylorientin,isoswertiajaponin,isoswertisin,2?-O-(2"?-methylbutyryl)isoswertisin,trollisin I,isoquercetin,and trolline were transformed by this model.LC-MSn techniques was used to analyze and identify the metabolites.And the metabolic pathway were inferred,in order to provide a basis for determining the effective components of the flowers.The phenolic acids in the flowers of T.chinensis contains methyl group.In the transformation of phenolic acids compounds,it was observed that demethylation(e.g.veratric acid and trollioside)and monoglycosylation(e.g.trollioside)occurred in phenolic acids.And hydroxylation(e.g.vitexin,isoswertisin and 2?-O-(2"'-methylbutyryl)isoswertisin),demethylation(e.g.isoswertisin and 2?-O-(2??-methylbutyryl)isoswertisin),acetylation(e.g.vitexin,2?-O-?-L-galactopyranosylorientin,isoswertisin,2"-O-(2???methylbutyryl)isoswertisin,trollisin I and isoquercetin),monoglycosylation(e.g.2"-O-?-L-galactopyranosylorientin,and isoquercetin)and hydrolysis(2"-O-(2??methylbutyryl)isoswertisin)occurred in flavonoids.Metabolites of larger molecular weight were detected in trolline,suggesting polymerization took place during transformation.The transformation of crude extract was in accord with the individual compounds.Individual compounds in crude extract were also inter-transformed,e.g.vitexin,isoswertisin,orientin,isoswertiajaponin,2"-O-?-L-galactopyranosylorientin and 2'-O-(2??-methylbutyryl)vitexin which may be transformed from their derivatives.The main reactions of demethylation,hydroxylation,acetylation,monoglycosylation and hydrolysis taking place during liver microsomal transformation are in favor of the elimination and toxicity reduction of the compounds from the flowers of T.chinensis by increasing their polarity.The activity of the flowers of T.chinensis is produced by the original compounds for their low or none transformation.The inter-transformation by rat liver microsomal of the individual compounds can also increase the activity of the flowers of T.chinensis which improves the effectiveness of the flowers in turn.