Component of the triterpene saponins (e.g. PPD-type ginsenosides) biosynthetic pathway (PubMed:25769286). Glycosyltransferase that catalyzes the biosynthesis of ginsenoside Rh2 from protopanaxadiol (PPD) (PubMed:25769286). (20S)-protopanaxadiol + UDP-alpha-D-glucose = (20S)-ginsenoside Rh2 + H(+) + UDP kcat is 0.384 sec(-1) with protopanaxadiol as substrate (at pH 8 and 40 degrees Celsius). Secondary metabolite biosynthesis; terpenoid biosynthesis. Belongs to the UDP-glycosyltransferase family.