【作者】 刘长姣；

【导师】 张守勤；

【作者基本信息】 吉林大学 ， 农业机械化工程， 2007， 硕士

【摘要】 红景天是中国传统中药之一,具有多种对人体有益的生物活性。目前红景天总黄酮的提取及其粗提物的抗氧化活性研究较少,本文以总黄酮为研究对象,应用超高压技术提取红景天中黄酮类物质,并测定提取物的抗氧化活性。为红景天的进一步应用提供支持。本文首次将超高压技术应用于红景天总黄酮的提取,通过单因素实验测定每个因素对红景天总黄酮得率的影响;通过均匀设计法优化试验条件,得到最优提取条件。选择超声提取法,回流法、浸泡法为对比试验方法。实验结果证明红景天总黄酮超高压提取法的得率最高,且提取时间比超声提取法缩短了57min,比回流提取法缩短了117min,比浸提法缩短了77min,进一步肯定了超高压提取法的诸多优点,为超高压提取技术在中药有效成分中的应用以及红景天总黄酮的提取技术提供依据。本文首次应用三种纯化方法分离纯化红景天总黄酮,醇沉法以黄酮损失率为指标;絮凝澄清法以壳聚糖为絮凝剂,以总黄酮损失率和透过率为评价指标,根据各因素对纯化效果的影响确定了絮凝澄清法纯化工艺条件;大孔吸附树脂分离法,以吸附率或解析率和总黄酮损失率为评价指标,根据各因素对纯化效果的影响确定了大孔吸附树脂分离法纯化工艺条件。试验证明大孔吸附树脂分离纯化法总黄酮纯度最高,更利于红景天总黄酮的分离纯化。应用DPPH法测定红景天提取物的抗氧化活性,并与人工合成抗氧化剂TBHQ进行对比。当红景天粗提物浓度在0.15 mg/mL以上时,其抗氧化活性高于人工合成抗氧化剂TBHQ(1.0mg/mL)的抗氧化活性;且超高压提取物的抗氧化活性高于其它三种方法的红景天提取物,这可为红景天作为抗氧化剂的进一步应用开发提供一定的实验依据。更多还原

【Abstract】 Rhodiola sachlinesis A.Bor is one of the most popular traditional Chinese medicines and the extract of the root of this plant has been proved to have many pharmacological effects. So far information on the extraction of flavonoids from Rhodiola sachlinesis is scarce, but some methods were used to extract flavonoids from other Chinese traditional medicines. Such as reflux, microwave extraction, supercritical CO2 extraction and so on. The methods mentioned have disadvantages such as complex procedure, long extraction time and the limitation of extracted components. Consequently,we chose Ultrahigh pressure extraction(UPE) as extraction method for the extraction of flavoniods from Rhodiola sachlinesis. This technique can improve the efficiency and reduce the power consumption.The flavonoids of Rhodiola sachlinesis needs to be purified and bioactivity text for its application. So this paper did some research on the purification and bioactivity texts of flavonoids and provided theoretical bases for its further application.The main content of this paper are as follows:1) UPE was used to extract flavonoids from Rhodiola sachlinesis for the first time. The optimum UPE condition was got by the Uniform design, the optimum regression equation and the optimum UPE conditions were shown below: Y=23.1090484+0.0445254X1+0.7462729X2+403.5558837X3-0.0000239X1X1+0.0002301X1X2-1.3896711X1X3-0.0.101624X2X2-1.4765610X2X3. R2=0.9998,F=534.8979>F0.05(8,1)=239,significant at P﹤0.05The optimum UPE condition was as follows: pressure (MPa)was 500MPa; ethanol concentrationwas 40%; solid/liquid ratiowas 1:70(gcm-3). The optimum extraction yield of flavonoids was 5.233%.Ultrasonic extraction, heat reflux and dipping extraction were chosen as the comparied methods. For the extraction time, UPE was 57min shoter than Ultrasonic extraction, 117min shorter than heat reflux and 77min shorter than dipping extraction. So UPE was the best method to improve the extraction yield of flavonoids and production efficiency.2) Three different methods were chosen as the text methods: ethanol purification, flocculant purification and macroporous adsorption resin purification. For the first method, the purity rate of flavonoids was 15.12%, and rate of getting power was 20.02%. For the second method, chitosan was used as flocculant, pH was 3, the amount of chitosan was 0.02mL/mL(sample), the purity rate of flavonoids was 18.21%, and rate of getting power was 19.06%. For macroporous adsorption resin purification, D101macroporous adsorption resin was used in this study, the amount of the sample used was 1/2 of the BV, pH was 5-6, the concentration of the sample was 3.66-2.44 mg/mL, the eluant was 70% ethanol-water solution, the amount of the eluant was five times of BV, the purity rate of flavonoids was 21.72%, and rate of getting power was 13.15%.This method can delete most of the protein and polysaccharide, the purity rate of flavonoids was the best, and the macroporous adsorption resin can be recovered. So macroporous adsorption resin purification was suitable for purifying the flavonoids from the Rhodiola sachlinesis extract.3) The antioxidant activity was tested in this paper. DPPH method was employed to test the antioxidant activity of the Rhodiola sachlinesis extract. We got that the antioxidant activity of Rhodiola sachlinesis extract with concentration above 0.15mg/mL was higher than TBHQ. At the same time the extracts of different extraction methods were also tested. The antioxidant activity ranking was: the extract of UPE>the extract of ultrasound extractiuon>the extract of dipping method>the extract of reflux.So we could get the conclusion that the UPE can not only improve the extraction efficiency, but also the bioactivity of the extract.更多还原