Chemical Constituents and Antiulcer Activity of n-Hexane Extract of Sanchezia nobilis Hook F. Leaves from Vietnam

Five compounds (1-5) were isolated from the leaves of Sanchezia nobilis collected in Nam Dinh province by chromatographic methods. These compounds were identified as: mangiferin (1), β-sitosterol (2), margaric acid (3), ursolic acid (4), oleanolic acid (5). Their structures were elucidated by spectroscopic methods, including mass spectrometry and nuclear magnetic resonance. These compounds were isolated from the leaves of Sanchezia nobilis for the first time. Screening of gastric and duodenal antiulcer effects on indomethacin induced gastric ulcer models showed that n-hexane fraction produced the highest antiulcer activity. Percentage inhibition of gastric ulceration of misoprostol was 22.86 %, while that of n-hexane fraction was 28.57 % (p < 0.05). Evaluation of gastric and duodenal antiulcer effects on acysteamine induced gastric ulcer models showed that this fraction was effective against gastric and duodenal ulcer (83.3 %), improved ulcer damage (54.17 %), significantly reduced the number of mean ulcer and ulcer index (2.00 ± 1.28) but it did not change the area of the ulcer.