Studies On Chemical Constituents And Biological Activities Of Two Medicinal Plants From Taebaek Mountain

The Qinling Mountains is not only the north-south boundary of the geography andclimate, but also the watershed of the two rivers, Yangtze River and Yellow River, whichforming wide variety of plants and one of the world most abundant terrestrial biodiversityregion. The Qinling Mountains are an important traditional Chinese medicine area in China.,serve as an important medicinal plant resource. Taebaek Mountain, also known as “HerbalKingdom” and “Natural Botanical Garden of Asia”, is the highest peak of the QinlingMountains, with the altitude of3767.2m. Due to the special environment, there are manyunique medical plants growing in this area. This research mainly focuses on chemicalconstituents and biological activities of Astragalus taipaishanensis and Potentilla fruticosawhich grow in Taebaek Mountain.10compounds were first isolated from these plant. It couldprovide a theoretical basis for the development and utilization of endemic medicinal plantresources and play a role for better protection of wild medicinal plant resources.1. The total phenolics, total flavonoids content and antioxidant activities of ethanolextracts (EE) and subfractions (petroleum ether fractions (PEF), ethyl acetate ftractions (EAF),n-butanol fractions (BF) and the aqueous phase (WF) of Astragalus taipaishanensis wereanalysis. EAF had the highest phenolics and flavonoids content and the strongest antioxidantactivities, which could be screening as the active part for further isolation and purification.2. Eight compounds were isolated and identified from the EAF part by using silica gelcolumn chromatography, gel filtration chromatography, preparative high performance liquidchromatography for isolation combined with modern spectroscopic techniques for structureidentification. Eight compounds were7,2’-dihydroxy-3’,4’-dimethoxy isoflavan(1),formononetin (2), isoliquiritigenin (3), p-hydroxy benzoic acid (4), vanillic acid (5), quercetin(6), kaempferol (7), ononin (8). These compounds were first isolated from this plant.3. The antioxidant activities of isolated compounds were evaluated by in vitro and in vivoantioxidant assays. Compound6which had the highest antioxidant activities against ABTS,DPPH, FRAP and H2O2induced Escherichia coli assays, while compound7had the strongest lipid peroxidation ability. The results first time revealed the chemical composition andbiological activity of Astragalus taipaishanensis, as well as provide a theoretical foundmentand technical support for better development, utilization and protection of this plant.4. Seven compounds were isolated and identified from the ethyl acetate fractions of thewhole plant, which were betulinic acid (1), oleanolic acid (2), quercetin (3), kaempferol (4),hyperoside (5), rutin (6) and caffeic acid (7). Compounds1and2were first time isolatedfrom this plant. The antioxidant activities of compounds were measured and the compound3had the strongest antioxidant capacity, followed by compound4.5. Total phenolics, flavonoids, tanning and six phenolic compounds (catechin, caffeicacid, ferulic acid, hyperoside, rutin, ellagic acid) content of different parts (leaves, flowers,stems) of Potentilla fruticosa were evaluated by colourimetric method and HPLC. The leavesof Qinghai had the highest content of total phenolics tannins catechin, caffeic acid, ferulicacid and hyperoside, the values were6.94%,8.04%,1.51±0.003,0.09±0.004,0.04±0.003and7.63±0.005mg/g, respectively. In addition, the flowers of Taebaek had the highestflavonoid content (8.46%), the rutin content of leaves of Taebaek was up to5.84±0.004mg/g;while the ellagic acid content (2.16±0.002mg/g) was the highest in flowers of Qinghai.6. The in vitro and in vivo antioxidant activities together with the in vitro and in vivoantifungal and antibacterial avtivities of different parts of Potentilla fruticosa were measured.Among all the tested samples, the leaves of Qinghai had both the strongest antioxidant,antifungal and antibacterial activities, which could be select as natural antioxidant andfungicides and bacteriacides for further development and utilization.