Studies On The Pharmacognosy Of Leaves Of Astilboides Tabularis Studies On The Chemical Components Of Leaves Of Corydalis Ambigua Var.amurensis And The Metabolism Of Ambinine In Rat

Astilboides tabularis,a perennial herb in Saxifragaceae,was used as an astringent to the intestine to relieve diarrhea.In this paper,the preliminary pharmacognosy study on the A.tabularis was research including microscopical identification of crude drug,hypoglycemic activities and chemical components of the water extract of A.tabularis.The microscopic characteristics which had the important distinction significance were obtained by observing permanent and temporary slide of A.tabularia and the vein islet number,the stomatal density and stomatal index were measured under the microscopy.In order to investigate the hypoglycemic effects of its water extracts,both epinephrine-induced and alloxan-induced diabetes model were established in our experiment.We found that the water extracts with dosage of 600 mg/Kg b.w.could significantly decrease the blood glucose level of diabetic mice.However,the low dosage groups(300 mg/Kg b.w.)showed effective hypoglycemic activity only in epinephrine induced diabetes model.The main constituents of the water extract were isolated by silica gel column chromatography,Sephedax LH-20 column and RP 18 column chromatography and their structures were characterized by Co-TLC and spectroscopic analysis as bergenin(1),catechol(2),pyrogallol(3),gallic acid(4),kaempferol(5),quercetin(6),quercitrin(7)and hyperoside(8),which are the main chemical components of the water extract of A.tabularis.Corydalis ambigua var.amurensis,a member of Corydalis genus in Papaveraceae family,is mainly distributed in the northeast of china.It could be used medicinally instead of C.yanhusuo which has the function of stimulating the blood circulation and analgesia.We previously found 16 new compounds and 1 new natural product from the tuber of C.ambigua var.amurensis.However,few publications literature specifically noted the chemical components of the aerial part of C.ambigua var.amurensis.These results prompted us to perform a systematic study to isolate abundant compounds in order to enrich the chemical composition of C ambigua var.amurensis.In present study,23 compounds,including one new compound with 22 known ones were isolated by silica gel column chromatography,Sephedax LH-20 column and preparative HPLC.Their structures were characterized by specctroscopicanalysis including 1D and 2D NMR,and HR-ESIMS data as(-)-cavidine(1),(-)-sinactine(2),tetrahydrocoptisine(3),d-corydaline(4),(6R,13S,14S)-6-acetylambinine(5),(6R,13-S,14S)-11-demethoxyambinine(6),(6R,13S,145)-ambinine(7),(-)-Adlumine(8),(6R,13S,14S)-2-demethylambinine(9),(6R,13S,14S)-3-demethylambinine(10),(6R,6aS,P)-isocorydine(11),(-)-corydalmine(12),(6R,8R,13S,14S)-8-hydroxymethyl-ambinine(14),(6R,13S,14S)-11-demethylambinine(15),(6R,13S,14S)-2,11-didemethylambinine(16),Dehydrocorydaline(17),13-Methylberberine(18),kaempferol-7-O-?-L-rhamnoside(19),p-hydroxycinnamic esters(20),tyrosol(21),Gallic acid(22),?-sitosterol(23)and Daucosterol(24).Among them,compound 18?22 were isolated for the first time in the C.ambigua var.amurensis.The antioxidant activities of the chemical components from the leaves of C.ambigua var.amurensis were determined by using DPPH and ABTS radical scavenging experiments.Based on the analysis of references and the results of our present study,the structure-activity relationships were discussed.The compounds with phenolic hydroxyl group showed different antioxidant activity and the activity of compound 19 and 22 were stronger than the positive control.In the DPPH radical scavenging experiments,the DPPH radicals scavenging activity of protoberberinealkoloids was stronger than that of hexahydrobenzophenanthridine alkaloids when they possessed the same number of hydroxyl groups.However,protoberberinealkoloids was weaker than that of hexahydrobenzophenanthridine alkaloids in ABTS radical scavenging experiments.These discoveries could be the guiding significance for seeking natural antioxidants.The ambinine was obtained from the leaf of C.ambigua var.amurensis which provide a material base for the future research.In our continuous study,6 metabolites were isolated from the urine,and the structures of the metabolisms were identified as:(6R,13S,14S)-6-acetylambinine(M1),(6R,13S,14S)-11-demethylambinine(M2),(6R,13S,14S)-2-demethylambinine(M3),(6R,13S,14S)-3-demethylambinine(M4),(6R,135,14S)-2,11-didemethylambinine(M5)and(6R,13S,14S)-3,11-didemethylambinine(M6).All the metabolites are phase I metabolites,and one metabolite was new compound(M6).Based on the identified metabolites,we could find that demethylation and acetylization were the most possible metabolic pathways.An ultra-performance liquid chromatography/quadrupole time-of-fight mass spectrometry(UHPLC/Q-TOF MS)method was employed to investigate the in vivo metabolism of ambinine in rats.Plasma,bile,urine and feces of rats were collected after a single oral administration with 200 mg/Kg dose of ambinine and then prepared by removing protein precipitation,solid phase extraction and ultrasonic extraction,successively.And then,the possible metabolites of ambinine were determined by mass spectrometric pattern of the parent compound and finally we speculated that reduction,demethylation,sulfationand glucuronidation were the metabolic pathways of ambinine in rats.