共查询到18条相似文献,搜索用时 93 毫秒
1.
2.
3.
4.
5.
儿茶素单体分离制备方法 总被引:1,自引:0,他引:1
茶叶中含有丰富的儿茶素类物质,占茶叶干重12%~24%,是茶叶中最具生理活性和保健功效的物质。文中对目前国内外纯化制备儿茶素的常见方法进行了综述。常见的儿茶素制备方法包括纤维素柱层析、葡聚糖凝胶(Sephadex LH—20)、硅胶柱层析、吸附树脂柱层析和高速逆流色谱等方法。通过这些方法制备的儿茶素单体纯度不高,仍需结合结晶、制备型液相色谱技术或膜分离技术进行进一步纯化,从而才能获得高纯度的儿茶素单体。在儿茶素单体的制备方法中,每种方法都有相应的优缺点。Sephadex LH—20柱层析分离的量较大,但是分离时间较长,而且Sephadex LH—20柱填料昂贵;高速逆流色谱分离效果较好,得到的儿茶素单体的纯度较高,分离时间相对要短,但是目前市场上只有分析型,分离的量相对少;硅胶材料廉价,但是分离的效果不佳,且分离过程相对繁琐,单体制备量较小;吸附树脂柱层析分离已实现EGCG单体的工业化生产,但在其他儿茶素单体的分离制备上尚不成熟。 相似文献
6.
7.
高速逆流色谱分离纯化荷叶黄酮槲皮素 总被引:1,自引:1,他引:0
以含量为4.4%的荷叶黄酮粗粉为原料,在优化高效液相色谱分析荷叶黄酮槲皮素条件的基础上,通过对不同溶剂体系的优选及操作参数的优化,建立了高速逆流色谱分离纯化荷叶黄酮槲皮素的技术方法。结果表明,采用流动相甲醇和0.4%磷酸、梯度(0min90%甲醇→10min60%甲醇→20min40%甲醇→40min20%甲醇)洗脱、检测波长360nm、流速1.0mL/min、柱温30℃、进样量20μL的技术参数可作为高效液相色谱分析荷叶黄酮槲皮素的方法;采用氯仿:甲醇:水(体积比8:10:5)为溶剂系统(上相为固定相,下相为流动相)、流速2mL/min、转速850r/min、进样量150mg的高速逆流色谱操作技术参数,可分离制备荷叶黄酮槲皮素单体,其纯度大于99%。 相似文献
8.
利用两步高速逆流色谱法分离纯化裂壶藻油脂中的二十二碳六烯酸(DHA)。经筛选,正庚烷-乙酸乙酯-甲醇-水(体积比15∶1∶15∶1)为第1步高速逆流色谱的两相溶剂体系,正庚烷-甲醇-水(体积比5∶6∶1)为第2步高速逆流色谱的两相溶剂体系。采用紫外检测器在波长210 nm处检测。利用单因素试验和响应面分析法对高速逆流色谱的分离条件:进样量、流动相流速、转速、分离温度进行优化试验,得到的最佳条件是:进样量180mg、流速3 mL/min、转速910 r/min、温度13℃。在此条件下,利用两步高速逆流色谱法分离纯化裂壶藻油脂中的DHA,用高效液相色谱和紫外检测联用技术检测DHA的纯度分别为90.06%和99.61%,回收率分别为为95.27%和93.81%。 相似文献
9.
《食品科学》2010,(12)
目的:确定高速逆流色谱分离制备高纯度丰城鸡血藤黄酮类物质刺芒柄花素的条件。方法:利用高效液相色谱测定刺芒柄花素在两相溶剂体系中的分配系数K值,通过K值优化确定高速逆流色谱分离的两相溶剂体系,并测定刺芒柄花素的纯度。结果:用于高速逆流色谱分离的两相溶剂体系为:正己烷-乙酸乙酯-甲醇-水(4:5:4:5,V/V),体系的上相为固定相,下相为流动相。高速逆流色谱分离条件为:流速2mL/min,转速800r/min,检测波长260nm,温度26℃。从鸡血藤乙醚提取物中可一步纯化得到活性成分刺芒柄花素,得率为16.1%,高效液相色谱检测其纯度达96.3%。结论:该溶剂体系分离结果可靠,可作为高效快速分离纯化刺芒柄花素的制备分离方法。 相似文献
10.
11.
Hu Jiang-Ning Shan Bin Deng Ze-Yuan Li Jing Fan Ya-Wei Ruan Zheng Liu Rong 《Food science and biotechnology》2010,19(6):1661-1665
A high-speed counter-current chromatography (HSCCC) method was developed for isolation of 5 alkaloids from lotus (Nelumbo nucifera Gaertn.) leaves. The 2-phase solvent system of HSCCC composed of light petroleum-ethyl acetate-methanol-water was set up
in 2- step separation process in the proportion of 3:5:3:5 for isolation of N-nornuciferine and armepavine, and in the proportion
of 1:5:1:5 for that of anonaine, pronuciferine, and nuciferine. The purity of anonaine (14.6mg), pronuciferine (29.7 mg),
N-nornuciferine (31.4 mg), nuciferine (22.1 mg), and armepavine (23.3 mg) isolated from 150 mg crude extract of lotus leaves
were examined as 95.6, 88.2, 92.5, 94.3, and 92.1%, respectively. 相似文献
12.
13.
High-speed counter-current chromatography (HSCCC) was used to separate an ethanolic extract of leaves of Mucuna sempervirens into fractions which were then detected their antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The fractions were grouped into seven larger fractions (components) based on their antioxidant activity. The seven components were isolated by preparative HPLC to yield 12 flavonoids and two phenolic acids identified by electrospray ionisation mass spectrometry and nuclear magnetic resonance analyses. The oestrogenic activity of the 12 isolated flavonoids was evaluated by the luciferase assay based on the MVLN cell line. The results indicate that leaves of M. sempervirens are a flavonoid-rich resource that may supply antioxidant and oestrogenic compounds to the human body. The HSCCC separation-DPPH radical scavenging detection could be widely applied for rapid screening and isolation of antioxidants from complex plant extracts. 相似文献
14.
Flavonoids from lotus (Nelumbo nucifera) seed embryos were fractionated over a macroporous resin chromatography into 2 main fractions (I and II), and subsequently identified by high‐performance liquid chromatography coupled with tandem mass spectrometry (HPLC‐MS2). Sixteen flavonoids were identified in lotus seed embryos, including 8 flavonoid C‐glycosides and 8 flavonoid O‐glycosides, in which the flavonoid C‐glycosides were the main flavonoids. Among them, 2 flavonoid O‐glycosides (luteolin 7‐O‐neohesperidoside and kaempferol 7‐O‐glucoside) were identified in lotus seed embryos for the 1st time. For further elucidating the effects of flavonoid C‐glycosides to the bioactivities of lotus seed embryos, we compared the differences of the flavonoids and their antioxidant activities between leaves and seed embryos of lotus using the same methods. The results showed the antioxidant activity of flavonoids in lotus seed embryos was comparable or higher than that in lotus leaves, whereas the total flavonoid content in seed embryos was lower than lotus leaves which only contained flavonoid O‐glycosides. The flavonoid C‐glycosides of lotus seed embryos had higher antioxidant properties than the flavonoid O‐glycosides presented in lotus leaves. This study suggested that the lotus seed embryos could be promising sources with antioxidant activity and used as dietary supplements for health promotion. 相似文献
15.
响应曲面法优化超临界二氧化碳萃取荷叶复方活性组分的工艺研究 总被引:1,自引:1,他引:0
运用CO2超临界萃取装置同时对荷叶、山楂、决明子和泽泻的复方物进行萃取,用Box-Bebnken响应曲面设计法,以萃取压力、萃取温度、夹带剂用量为自变量,以总生物碱、总蒽醌、总三萜类物质得率3个指标用多指标实验全概率法处理后所得的全概率公式分为响应指标,用回归方程的方差分析检验模型的准确性。最优化的条件为萃取压力30.93MPa,萃取温度50.04℃,夹带剂用量2.16mL/g。在此条件下提取3次结果与理论预测值相近。因此,基于多指标实验全概率公式分的响应曲面法所得的优化提取工艺参数准确可靠,具有实用价值,可用于荷叶复方降脂产品的开发。 相似文献
16.
Qi-he Chen Ming-liang FuMiao-miao Chen Jing LiuXiao-jie Liu Guo-qing HeShou-cheng Pu 《Food chemistry》2012,132(1):619-623
Xanthohumol (XN) and related prenylflavonoids are the main bioactive components of hops (Humulus lupulus L.). The current work is to investigate the use of high-speed counter-current chromatography (HSCCC) in search for high isolation of xanthohumol from hops. A solvent system consisted of n-hexane-ethyl acetate-methanol-water at a volume ratio of 5:5:4:3 was employed. The results demonstrated that the constructed method could be well applied for the isolation of xanthohumol from hops extract. After HSCCC isolation procedure, the purity of xanthohumol was over 95% assayed by HPLC and the yield of extraction was 93.60%. The chemical structure identification of xanthohumol was carried out by UV, 1H NMR and 13C NMR. The present results demonstrated that xanthohumol could be efficiently obtained using a single HSCCC step from H. lupulus L. extract. 相似文献
17.
目的:筛选荷叶生物活性效应标志成分,为荷叶质量及活性评价提供评价指标。方法:采用薄层色谱法分析鉴别、高效液相色谱法测定荷叶的8种黄酮、生物碱成分,进行荷叶抗氧化、抑制脂肪酶的活性效应成分相关性分析;薄层色谱法分离分析荷叶特征色谱斑点,聚类分析法筛选质量标志成分;结果:定量分析标志物荷叶碱为2.48±1.80mg/g,2-羟基-1-甲氧基阿朴啡为0.61±0.33mg/g;荷叶有较强的抗氧化及抑制脂肪酶活性;薄层鉴别标志物为2-羟基-1-甲氧基阿朴啡、荷叶碱。结论:荷叶中黄酮、生物碱成分含量测定为荷叶多成分的含量测定提供一定技术支持。2-羟基-1-甲氧基阿朴啡、荷叶碱为薄层鉴别标志物及抗氧化、抑制脂肪酶活性效应的质量评价成分,有助于全面评价荷叶药材质量及生物活性效用。 相似文献
18.
应用高速逆流色谱法分离制备了白胡椒中3种单萜类化合物。以V(叔丁基甲基醚)∶V(甲醇)∶V(水)=2∶1∶1为两相溶剂系统,上相为固定相,下相为流动相,在主机转速900 r/min、流动相流速2.5 mL/min条件下,从2.76 g样品中一步分离制备得到3,7-二甲基-2-辛烯-1,6,7-三醇35 mg,对薄荷烷-1,2,8-三醇-2-O-β-D葡萄糖苷55mg,5-羟基龙脑-2-O-β-D葡萄糖苷40mg,经高效液相蒸发光散射检测器(HPLC-ELSD)检测纯度均达95.0%以上,各化合物结构经质谱和核磁共振氢谱、碳谱鉴定。研究结果表明,利用该方法可以对白胡椒中的单萜类化合物进行快速的分离和纯化,且制备量大,分离效率高。 相似文献