A study conducted by Assoc. Prof. Dr. Pharkphoom Panichayupakaranant, Director of Research in Pharmaceutical Biotechnology, and Mr. Apirak Sakunpak, a Ph.D. candidate under the support of the Royal Golden Jubilee Ph.D. Program in the Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences, Prince of Songkla University, investigated the anti-bacterial activity against gastrointestinal pathogenic bacteria of indigenous plants, specifically located in southern Thailand.

Based on the main findings, for the first time ever, substances that have not only potential anti-bacterial activity against gastrointestinal pathogenic bacteria but also potential anti-cancer activity were extracted from Garcinia cowa leaves.

Twenty-two edible plant extracts were evaluated for their antibacterial activity against Helicobacter pylori, which can infect the digestive system. The results of the study found that only Garcinia cowa leaf extracts exhibited antibacterial activity against all tested bacteria. Purification of the extract of Garcinia cowa leaves using an antimicrobial assay-guided isolation provided a new polyprenylated benzophenone, Chamuangone, which displayed satisfactory antibacterial activity against Streptococcus pyogenes.

Also, the new polyprenylated benzophenone, Chamuangone, was capable to inhibit the growth of protozoa. For this reason, Chamuangone was used to experiment with lung cancer cells and leukaemia cancer cells, and it exhibited anti-cancer activity as well. This achievement can then lead to the improvement of more effective substances having potential anti-cancer activity.