Comparative effect of garlic (Allium sativum), onion (Allium cepa), and black seed (Nigella sativa) on gastric acid secretion and gastric ulcer

Naheed Amir, Amina Al Dhaheri, Najla Al Jaberi, Fatma Al Marzouqi, Salim MA Bastaki
Department of Pharmacology and Therapeutics, Faculty of Medicine and Health Sciences, UAE University, Al Ain, United Arab Emirates

Abstract: Protective roles of raw and boiled garlic (Allium sativum) and onion (Allium cepa) in comparison with black seed (Nigella sativa) on acidified ethanol-induced gastric ulcers and gastric acid secretion in rats in vivo have been investigated. Raw or boiled Nigella sativa, garlic, or onion significantly inhibited histamine stimulated acid secretion, whereas on basal acid secretion, onion and garlic significantly stimulated secretion but Nigella sativa had no effect. Raw Nigella sativa and garlic showed a significant decrease in the ulcer index when compared with the control at all doses (0.25 g/kg, 0.5 g/kg, and 1 g/kg) tested, whereas onion-only, at doses of 0.5 g/kg and 1 g/kg, significantly reduced the ulcer index. Boiled Nigella sativa showed equal potency to raw Nigella sativa in decreasing ulcer index, but boiled garlic and onion showed reduced potency. The results of this study demonstrate the protective role of raw Nigella sativa, garlic, and onion against ethanol-induced gastric ulcers and gastric acid secretion. Boiling did not affect the protective effect of Nigella sativa on gastric ulcers.

Keywords: Nigella sativa, onion, garlic, acid ulcer