Standardization Research Of Rhodiola Crenulata

In order to explore and make full use of the resource of Rhodiola L. and improve the quality control system of products, the standard extracts, chemical component, antioxidant activity and HPLC finger map of Rhodiola crenulata, which was recorded in Chinese pharmacopoeia published in 2005 were studied.A method to obtain the standard extracts was developed. The root of Rhodiola crenulata was extracted by 70% ethanol, the extracted solution was concentrated to remove ethanol. Then the concentrated solution was chromatographed on DM-130 macro-porous absorbent resin column. Elute by water to remove impurities first, then by 30%, 60% ethanol-water gradiently, and the two standard extracts were gained. The products were stable and the recovery were 10.87% and 5.43% respectively, The process was simple and the price was low . It was suitable for industrial application. Ten compounds were isolated from the two different parts of the standard extracts by column chromatrography(CC) with different solid-phase including silica gel and Sephadex LH-20 and MCI-gel CHP20 as well. All the compounds were identified by 1H NMR and 13C NMR spectrum data, which were salidroside, tyrosol, kaempferol, kaempferol-7-O-α-L-rhamnoside, crenulatin, rhodinin, rhodiosin, caffeic acid respectively. The standard salidroside with the purity of 99.09% was also made by further purification of the 30% ethanol-water eluated from DM-130 macro-porous absorbent resin column of 70% ethanol extracts of Rhodiola crenulata.The antioxidant activity of the two part standard extracts and the eight pure compounds was tested. According to the DPPH assay, both of the two parts had high antioxidant activity with the SC50 2.8 and 4.8μg/mL respectively, and the activity of the four flavone was the same with Vc. This may be the scientific base for its both medical and edible use.