Tibetan Medicine Rhododendron Primulaeflorum In Vitro Antioxidant Screening And Chemical Composition Analysis

Rhododendron primulaeflorum Bur. et Franch. is one of the original plant of Tibetan medicine "Dali". It has been contained in Flos Rhododendri Anthopgonoidi in1995edition of Tibetan Medicine Standard of Ministry of Public Health of Peoples Republic of China (Volume I), and first set out in the " Somaratsa " which was published the8th century, which described that Dali mainly treated Long diseases, Chiba diseases and Peigen diseases. The free radical has a close relationship with the development of variety of diseases, and the antioxidants could remove free radical effectively, that could prevent disease. With the deepening of free radical’s research, the study on screening the antioxidant components of the drugs is increasingly subject to the attention of the people.Objective:Screening the antioxidant components of Tibetan medicine Rhododendron primulaeflorum is to provide the material basis.Methods:1. Antioxidant capacity of Rhododendron primulaeflorum and its different officinal parts was preliminarily screened by HPLC with Pre-column derivatization. TLC-Bioautography could distinguish between active and inactive compounds of Rhododendron primulaeflorum. On-line HPLC-DPPH-MS assay was used for the screening of antioxidant compounds in Rhododendron primulaeflorum.2. To study on the quantitative determination of antioxidant compounds hyperoside, quercitrin and quercetin in Rhododendron primulaeflorum by HPLC.Results:1. Tibetan medicine Rhododendron primulaeflorum and its different officinal parts had good antioxdant capacity, and more abundant antioxidant components. Then, the antioxidant ability of hyperoside and quercitrin equals to Vitamin C.The antioxidant ability of flowers was better than the leaves, and the antioxidant components of flowers were more than the leaves. 2. The results of the quantitative determination of hyperoside, quercitrin and quercetin had large differences between the different batches of Rhododendron primulaeflorum. Then, the content of hyperoside in the flowers, leaves and branches has descending order; the content of quercitrin in the flowers was more than the content in the leaves and branches. Furthermore, quercetin in the branches has a higher content.Conclusion:1. The methods of HPLC with Pre-column derivatization, TLC-Bioautography and on-line HPLC-DPPH-MS assay could evaluate the anti-oxidation activity of the sample from quantitative and qualitative.2. The different of the antioxidant capacity and the content of antioxidant components between in the flowers and leaves of Rhododendron primulaeflorum, initially revealed the material basis for the efficacy of the flowers and leaves.