An anti-ulcerogenic flavonol diglucoside from Equisetum palustre L.
BACKGROUND
The aerial parts of Eqiusetum palustre L. is used to treat peptic ulcer in Karaman, Turkey.


OBJECTIVE
The present study was undertaken to evaluate the in vivo gastroprotective potential and structure elucidation of the active constituent(s) through bioassay-guided fractionation procedures by using ethanol (EtOH)-induced ulcerogenesis model in rats.


METHODS
The 80% ethanol extract of the aerial parts was subjected to subsequent separation procedures such as solvent-solvent partition and column chromatography through bioassay-guided fractionation techniques to isolate the active anti-ulcer component(s) by using the EtOH-induced ulcer model in rats. The ulcer index was used to evaluate and to calculate the gastroprotection percentage.


RESULTS
The subextracts, n-butanol and remaining H2O, of Equisetum palustre showed potent in vivo gastroprotective activity. Bioassay-guided fractionation has revealed that a flavonol diglucoside, was isolated as an active constituent from the n-BuOH subextract of Equisetum palustre. Structure elucidation by standard spectroscopic techniques (1H NMR, 13C NMR and DEPT, etc.) revealed that this compound as kaempferol-3-O-1''-beta-d-glucopyranosyl-3-O-1'''-beta-D-glucopyranoside, which provided remarkable protection at 250 and 500 mg/kg doses (69.5 and 98.5% ulcer inhibition, respectively) against ethanol-induced gastric lesions.


CONCLUSIONS
Experimental data confirmed the ethnobotanical usage of Equisetum palustre, with scientific evidence, in Turkey. Additionally, kaempferol-3-O-1''-beta-D-glucopyranosyl-3-O-1'''-beta-D-glucopyranoside, a known compound, was defined as an anti-ulcerogenic compound in the present work for the first time.
Gurbuz
Ilhan
I
Gazi University, Faculty of Pharmacy, Department Pharmacognosy, Etiler, 06330 Ankara, Turkey.
Yesilada
Erdem
E
Ito
Shigeru
S
D000818:Animals; D000897:Anti-Ulcer Agents / Q000627:therapeutic use*; D004195:Disease Models, Animal; D020829:Equisetum; D000431:Ethanol; D005260:Female; D005753:Gastric Mucosa / Q000187:drug effects*; D044949:Kaempferols / Q000737:chemistry / Q000302:isolation & purification / Q000627:therapeutic use*; D008297:Male; D016595:Misoprostol / Q000627:therapeutic use; D008517:Phytotherapy; D035261:Plant Components, Aerial; D010936:Plant Extracts / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013276:Stomach Ulcer / Q000139:chemically induced / Q000188:drug therapy*; D014421:Turkey
D000897:Anti-Ulcer Agents; D044949:Kaempferols; D010936:Plant Extracts; C540592:kaempferol-3-O-1''-beta-d-glucopyranosyl-3-O-1'''-beta-D-glucopyranoside; D016595:Misoprostol; D000431:Ethanol