Resource investigation about Tibetan medicine Rhodiola kirilowii / 中国中药杂志

The investigation aims to better understand the resource status of Rhodiola kirilowii, analysis the suitable habitat of wild Rh. kirilowii and protect the wild resources of Rh. Kirilowii, promoting the sustainable utilization of Rh. kirilowii resources. In this paper, we investigated the wild resources of Rh. kirilowii in 16 counties of Sichuan, Qinghai, Gansu and Yunnan by means of investigation and sampling investigation combined with interview. The results showed that the population densities of wild Rh. kirilowii in 4 provinces were very different and the reserve of wild resources decreased gradually in many areas. According to the survey results, the current total reserve of Rh. kirilowii in four provinces was about 1 100 t. The reserve of wild Rh. kirilowii in Sichuan province was the largest. Simultaneously, the Rh. kirilowii had a certain ecological value. We found that a sand control base with planting Rh. kirilowii was set up in Hongyuan County of Sichuan Aba Tibetan and Qiang Autonomous Prefecture. The investigation provides a scientific basis for the development and sustainable utilization of Rh. kirilowii resources.

Antioxidant activities of cold-nature Tibetan herbs are signifcantly greater than hot-nature ones and are associated with their levels of total phenolic components / 中国天然药物

Tibetan medicinal plants have been used for more than 2 000 years. In order to find their differences in antioxidant activity, total phenolics and total flavonoids between "hot-nature" and "cold-nature" herbs, we investigated the antioxidant activities of 40 Tibetan herbs from Qinghai plateau, with 20 herbs in cold-nature and 20 herbs in hot-nature. Antioxidant capacities were evaluated by the following methods: scavenging ABTS•(+) (2, 2'azinobis-(3-ethylbenz-thiazoline-6-sulfonic acid), scavenging O2•(-), and Ferric-reducing antioxidant power (FRAP). The effects on inhibition of mitochondrion lipid peroxidation were determined by measuring the formation of TBARS (Thiobarbituric acid reactive substrates). Total phenolics and flavonoids were estimated by Folin-Ciocalteu and NaNO2-Al(NO3)3-NaOH colorimetric methods. Interestingly, the cold-nature herbs displayed higher antioxidant activities than the hot-nature ones, corresponding to nearly three-fold higher total phenolic contents in the cold-nature herbs. Moreover, the antioxidant activities correlated linearly with the levels of total phenolics for both cold-nature and hot-nature herbs, but only with the levels of total flavonoids for the hot-nature herbs. The results suggested that the phenolic compounds, but not the flavonoids, play the major role in antioxidant capacities of the cold-nature herbs. These findings could shed new lights on the study the theory of Tibetan medicine.