紅景天之活性成分與生物活性回顧

從天然的食材或藥材中尋找有利於人體生理機能的成分，進而發展成健康食品，是現今許多健康食品產業的開發來源，中草藥即是重要的開發來源，而含紅景天的產品亦可見於市場上。紅景天為景天科(Crassulaceae)紅景天屬(Rhodiola sp.)多年生草本植物或亞灌木植物，主要分布於不丹、錫金、尼泊爾以及中國大陸的西藏、四川、雲南等地，紅景天屬植物全球共約有200多種。本論文以紅景天做為研究回顧之主題，並就其主要的活性成分紅景天苷(salidroside)的製備方法與藥理作用進行探討。論文中包含紅景天植物的種類與分佈，成份回顧發現紅景天含有黃酮類(flavonoid)、揮發油(volatile oil)、苷類(glycoside)、香豆素(coumarins)、谷甾醇(steroid)、鞣酸(tannins)、有機酸(organic acids)、酚類(phenols)、萜類(terpenoid)、脂肪(fats)及蛋白質(proteins)等。紅景天粗抽物的藥理活性則有：抗疲勞、抗缺氧、抗衰老、抗病毒、抗腫瘤作用、抗微波輻射及解毒作用等。而其中紅景天苷(salidroside)則具有抗氧化、抗貧血、抗第二型糖尿病、降低氧化壓力、解毒、保護神經元等活性。紅景天苷的製備方法發現醇沉法優於乙酸鉛沉澱法，微波輔助提取優點是提取所需時間較醇提時間短。超音波提取紅景天苷的提取率最佳溫度為60℃，又以能夠恆溫的條件較無恆溫的優。粗抽物最後再經由分配萃取與管柱層析方法後即可取得大量之純化合物。本論文針對紅景天中活性成分salidroside建立快速製備之方法。將紅景天以95%乙醇熱迴流抽取後，再經由分配萃取與管柱層析法即可得純化物salidroside，並建立紅景天中salidroside含量檢測方法。此方法可提供未來大量純化salidroside之使用。

關鍵字

景天科；紅景天苷苷類；藥理活性

並列摘要

Many of functional food are developed from natural sources, and Chinese herbal medicine is an important one. The products, containing the Rhodiola, have also been developed in the market. Rhodiola, belong to Crassulaceae family, is a perennial herb and distribute in Bhutan, Sikkim, Nepal and China's Tibet, Sichuan and Yunnan. The Rhodiola genus has more than 200 plants around the world. The aims of this thesis were studying on the constituents and bioactivities of Rhodiola genus, systematically, and preparation methods and pharmacological activities of main active components, salidroside. It includes Rhodiola category and distribution, phytochemicals, and pharmacological activities. The phyochemical study have reported that this genus contained flavonoid, volatile oils, glycosides, coumarins, steroid, tannins, organic acids, phenols, terpenoids, fats and proteins. The crude extract of Rhodiola exhibited anti-fatigue, anti-anoxia, anti-aging, anti-virus, anti-tumor, anti-microwave radiation and detoxcification. The bioactivities of salidroside exhibited ant-oxidative, anti-anemia, anti-diabetes, reduce oxidative stress, detoxification, and neuron protection effects. The alcohol precipitation was optimal method than lead acetate precipitation for preparation of salidroside, and using ultrasonic technology can also improve the alcohol precipitation method. The optimal temperature was 60 ℃for ultrasonic extraction under thermostatic conditions. Finally, the crude extract was subjected on column chromatography to obtain salidroside. In this thesis, we also established the rapid preparation method for salidroside purification in large scale. The powder of R. crenulata was extracted with 95% ethanol, then, the extract was partitionated with different polarity solvents. The sublayer, containing salidroside, was subjected on column chromatography to yield salidroside. Quantitative this method maybe provide the purification method for salidroside for large-scale in the future.