An endophytic bacterium isolated from Panax ginseng CA Meyer enhances growth, reduces morbidity, and stimulates ginsenoside biosynthesis

Ginseng (Panax ginseng C.A. Meyer) is known for its therapeutically useful ginsenosides that have anticancer and other pharmacological effects. However, its low levels in plants and the high costs of chemical synthesis make ginsenosides commercially non-viable; as such, strategies for increasing ginsenoside yield are of great interest. The present study reports the isolation of eight novel endophytic bacteria from ginseng leaves, the highest ginsenoside concentration of microbial transformed strain was identified as Paenibacillus polymyxa. Inoculation of ginseng plants with P. polymyxa by foliar application combined with irrigation enhanced plant growth parameters, reduced morbidity, and increased plant concentration of the ginsenosides (Rg(1), Re, Rf, Rb-1, Rg(2), Rb-2, Rb-3, and Rd) in field experiments. These results indicate that P. polymyxa isolated from ginseng is a beneficial endophytic bacterium with biocontrol properties that can enhance the yield and quality of this medicinal plant. (C) 2014 The Authors. Phytochemical Society of Europe. Published by Elsevier B.V.