Ulcer is a serious oxidative stress induced disease with complex pathologic events including upregulation of H+K+ ATPase of parietal cell (PC) membrane, damage of mucin layer around PC, PC-DNA damage etc. The polysaccharide (GRPP) fraction and antioxidant extract (GRAOX) of ginger was examined for their ability to inhibit H+ K+ ATPase. Results indicated that the inhibition of H+ K+ ATPase activity which causes acidity in the lumen of the stomach, also exhibited better H+K+ ATPase inhibition (PPI) at the IC50 of 27.2 μg (GRPP) and 16.5 μg GAE (AOX) respectively than the known antiulcer proton pump blocker Lansoprazole (19.3 μg). Further the antioxidant activity in antioxidant extract (GRAOX) by various assay systems was examined such as Reducing power, Free radical scavenging (FRS), DNA and cytoprotection systems etc. GRAOX exhibited concentration dependent reducing power ability at 5-25 μg equivalent of phenol. FRS activity with IC50 of 6.8 μg equivalent of phenol etc. At 0.3 μg level GRAOX offered >；80% protection to DNA and against FeSO4-Asc'orbate induced oxidation. The major active phenolic components were identified as Gallic acid/Tannic acid (46%), and Cinnamic acid (51%).
