Study On Saponins Transformation Of Notoginseng Root Rot

Medicinal plants of the genus Panax are famous in traditional Chinese medicine, P. ginseng, P. notoginseng, P. quinquefoium and P. japonicus were inconsistent with the "Chinese Pharmacopoeia". The main active ingredients of this genus triterpenoid were considered saponins. The reported active chemical components of saponin compounds have been reviewed.Notoginseng is the most famous traditional Chinese medicine in Yunnan province, but its growing environment is almost warm and wet, easy to infect root rot. The saponins of normal notoginseng and its root rot were analyzed using High performance liquid chromatography-mass spectroscopy (LC-MS), and the oxidation level (H2O2 and MDA) of the fresh herbs were detecting.13 peaks in the normal notoginseng were identified, and 9 new transformated compounds from its root rot were detected. Moreover, the oxidation level was significantly increased after infected root rot diseases (P<0.01). The saponins of notoginseng root were transformated may be due to increase the oxidation levels by disease induced.Based on the above speculation, the oxidation experiments of Panax notoginseng saponins (PNS) in vitro were transformated by hydrogen peroxide under the catalysis of Rose Bengal. The reaction products of PNS were similar as Notoginseng root rot. In order to simplify the experiment, and explore the transformation mechanism, the pure compositions (ginsenoside Rgl, ginsenoside Rbl, ginsenoside Rd, ginsenoside Re, notoginsenoside R1) in PNS was isolated. And ginsenoside Rgi and ginsenoside Rbi was used as the substrate for oxidation transformation experiments in vitro, each three kinds of transformation products were obtained and identified as compound 6 (24-hydroxy-24-hydro-ginsenoside Rgi); compound 7 (24-hydroxy-25-peroxy-23-en-24-hydro-ginsenoside Rg1); compounds 8 (25-peroxy-23-en-24-hydro-ginsenoside Rgi); compound 10(24,25-dihydroxy-24-hydro-ginsenoside Rbi); compound 11(24,25-epoxy-24-hydro-ginsenoside Rbi); compounds 12 (24-peroxy -25(26)en-24-hydrogenation ginsenoside Rbi).These transformation products were similar as the some reported trace saponins from notoginseng herb, the 24,25 carbon double bond was oxidated.