Studies On Flavonoids And Caffeic Acid Derivatives Of Scorzonera Austriaca Willd

Background:Scorzonera austriaca Willd,also called black salsify,soil ginseng,and lycopene,etc.,is a kind of perennial herb from the asteraceae family.Scorzonera austriaca willd bloom in early spring with yellows flowers,and looks like thousand-headed chrysanthemums.They are both flowery,edible,and pharmaceuitical,usually picked in summer and autumn.In civil,scorzonera austriaca willd are applied for clearing heat and swelling;as a diet,it is fried together with tofu,which is suitable for diseases such as lung deficiency,cough,deficiency,diabetes,acne,and swollen poison.In general,scorzonera austriaca willd is widely used in folk.As a traditional folk herbal medicine,many researches have been conducted on scorzonera austriaca willd systematically.It has been demonstrated that scorzonera austriaca willd can take lots of pharmacological roles including liver protection,anti-virus,anti-inflammatory,anti-diarrhea and other effects,and liver protection effect is particularly remarkable.Objective:After referring to the literature on flavonoids and caffeic acid derivative compounds in scorzonera austriaca willd,it was found that the flavonoids and caffeic acid derivative compounds are the material basis for the pharmacological function of liver protection,antibacterial and antiviral.It will be of great significance to study its protective effect on the liver especially based on the current prevalence of liver disease.Current researches on scorzonera austriaca willd is circumscribed due to the fact that only 15 species of flavonoids and 5 species of caffeic acid and derivatives have been isolated.For the purpose of developing and utilizing the medicinal value of scorzonera austriaca willd more sufficiently and rationally,this article studied the chemical constituents of flavonoids and caffeic acid derivatives in scorzonera austriaca willd systematically.Methods:1.Extraction of total flavonoids from scorzonera austriaca willd: Soak the whole plant of scorzonera austriaca willd with 70% ethanol for three times,and one week for each time.Combine all the extracts,concentrate under reduced pressure,dissolve the resulting cream in water,filter,add the filtrate to the D101 macroporous resin,collect eluent of 60% ethanol,recover and dry under reduced pressure,and gather the solid of total flavonoids.2.Isolation and purification of flavonoids and caffeic acid derivatives: isolate the monomer compound from total flavonoids of scorzonera austriaca willd by means of macroporous resin column chromatography,thin-layer chromatography,normal and reversed phase silica gel column chromatography,recrystallization,and semi-preparative HPLC methods3.Structure identification: The chemical structures of monomer compounds obtained were identified by physicochemical properties and spectral analysis techniques.Results:After comprehensive use of the methods above,six compounds were isolated from total flavonoids from scorzonera austriaca willd and their structures were identified as follows:(I): 4-O-Caffeoyl quinic acid(II): Isoorientin 2''-O-?-D-glucoside(III): 4,5-O-Dicaffeoyl qunic acid(IV): Ethyl caffeate(V): Luteolin(VI): P-hydroxyl ethyl cinnamateConclusion:All of compounds are first isolated from Scorzonera austriaca Willd.