Suhua Zhu, Chengxiang Fang, Shiqiao Zhu, Fang Peng, Luozhen Zhang, Chengpeng Fan, Inhibitory Effects of Gynostemma Pentaphyllum on the UV Induction of Bacteriophage 5 in Lysogenic Escherichia coli. Current Microbiology. Aug. 2001.

In this study at Wuhan University in China they examined the effect of Jiaogulan on the growth of bacteriophages (viruses that attack bacteria, e-coli and cholera are both examples). They found that Jiaogulan did inhibit the growth of the bactriophages. They also found through Magnetic Resonance Imaging that Jiaogulan was an effective scavenger of free radicals.