Phytochemical and Pharmacological Studies on Convolvulus fatmensis Ktze.

Abstract

Two aglycones flavonoid compounds were isolated from Convolvulus fatmensis Ktz. using column and preparative paper chromatography and identified by using ¹HNMR, ¹³CNMR and UV shift reagent, these compounds were kaempferol and quercetin. Four coumarin compounds were isolated and identified as umbelliferone, scopoletin, asculetin and scopoline for the first time. Two phenolic acids were also isolated in the same manner and identified by spectroscopic methods, they are ferulic acid and caffeic acid. The methanol extract of Convolvulus fatmensis was evaluated for its potential antiulcerogenic, diuretic and hepatoprotective effects as well as for its acute toxicity. The antiulcerogenic effect was evaluated against acute (ethanol model) and prolonged (aspirin model)-gastric ulceration. The results revealed that, oral administration of the methanol extract (400 mg/kg bw) significantly reduced the alcohol-induced gastric ulcers (curative ratio; 32.6%). It also produced high curative ratio (75%), decreased the number of gastric ulcers, total acidity and total protein in aspirin-induced gastric ulcer (P < 0.05). Oral administration of 500 mg/kg bw methanol extracts did not affect the urine output, or sodium excretion while potassium and chloride excretion were significantly increased. The higher dose (1000 mg/kg bw) significantly increased the sodium, potassium and chloride excretion but did not affect urine volume. Moreover, it produced mild hepatoprotective effect against CCl₄-induced hepatotoxicity as indicated from serum biochemical and histopathological changes. No signs of acute toxicity were observed after oral administration of doses up to 2.75 g/kg bw.