Grape Extracts May Be Effective Against Harmful Gut Bacteria

H. pylori is the bacterial agent most commonly associated with peptic ulcers, gastritis, mucosa-associated lymphoid tissue lymphoma, and gastric cancer. Antibiotic therapy has proven effective at providing initial relief, however resistance can develop over time and relapse can occur. Previous studies have examined other natural plant extracts with anti-H. pylori activity such as garlic, broccoli, cranberries and green tea, however, grapes have yet to be evaluated despite being well known for their high levels of antioxidants and polyphenols.

The antibacterial effects of extracts from red, white, black and muscadine grapes as well as the pure compounds resveratrol, ellagic acid, and myricetin were tested for anti-H. pylori activity using agar dilution, laser scanning microscopy and cell proliferation. Following 24 hour treatment, results showed that muscadine grape skin extract had the highest anti-H. pylori effect, followed by muscadine grape synergy and seed extract. Additionally, two of the three compounds, resveratrol and ellagic acid, also inhibited H. pylori.

"In this study, grape extracts and their compounds were effective at inhibiting H. pylori in vitro, with highest efficacy by muscadine grape skin extract," say the researchers.