微波提取山楂中黄酮类化合物的工艺优化

以总黄酮得率为指标,采用微波法辅助提取山楂叶中的总黄酮,选取浸提时间、乙醇体积分数、微波辐射时间、液固比等参数进行单因素试验,选择影响较大的因素,利用Design-Expert 8.0.5b进行响应面分析,得到优化的提取工艺条件:乙醇体积分数56%,液固比51 m L/g,微波辐射时间3.7 min,在此条件下,山楂叶中总黄酮得率为8.923%。     

天花粉中总黄酮提取工艺研究

本研究优化了天花粉中总黄酮的提取工艺,采用Al(NO3)3-Na NO2比色法测定了天花粉中总黄酮的含量。在单因素试验的基础上,采用L9(34)正交试验,以天花粉中总黄酮提取率为指标,探讨了甲醇体积分数、料液比、提取温度、提取时间对天花粉中总黄酮提取率的影响。结果表明最佳提取工艺参数为:甲醇体积分数50%、料液比1∶15、提取温度70℃、提取时间90 min。在最佳工艺条件下测得天花粉中总黄酮平均含量为0.1184 mg/g。该方法操作简单,稳定性和重复性好,本实验首次测定了天花粉中总黄酮含量,为天花粉药材质量控制提供了依据。     

响应面法优化合萌总黄酮提取工艺

目的:利用响应面法优化合萌中总黄酮的提取工艺条件。方法:通过单因素试验分别考察提取时间、乙醇体积分数、液固比、提取温度及提取次数对合萌总黄酮得率的影响,并选取提取时间、乙醇体积分数、液固比、提取温度为影响因子,应用响应面法优化提取工艺。结果:合萌总黄酮的最佳提取条件为:提取时间60 min,乙醇浓度65%,液固比(g∶m L)25∶1,提取温度90℃,在此条件下,合萌总黄酮得率为4.08 mg/g,接近模型预测值4.11 mg/g。结论:响应面法在一定程度上可以提高合萌总黄酮得率,表明响应面法用于合萌总黄酮提取工艺的优化具有可行性。     

竹柏叶总黄酮不同提取方法比较

本研究采用正交试验设计分别优选回流提取和超声波提取竹柏叶总黄酮的最佳工艺条件。在单因素试验的基础上,以总黄酮得率为参考指标,选取液料比、乙醇体积分数、温度和时间4个影响因子,进行正交试验,分别确立回流提取和超声波提取最佳提取工艺条件。结果表明,回流提取优化工艺条件为:液料比30∶1(m L∶g),乙醇体积分数为70%,回流时间1.0 h,回流温度80℃;超声波提取优化工艺为:液料比25∶1(m L∶g),乙醇体积分数为70%,超声时间30 min,超声水浴温度60℃。两种提取方法的最终提取效果比较,回流提取的总黄酮得率为15.522%,超声波提取总黄酮得率为13.637%,回流提取法总黄酮得率高于超声波提取法。本实验结果为后续竹柏叶总黄酮的开发利用提供了参考。     

红果参叶中总黄酮的提取工艺初步探讨

目的:研究红果参叶中总黄酮的最佳提取工艺条件。方法:利用单因素和正交试验,考察提取时间、乙醇溶液体积分数、液固比3个因素对总黄酮得率的影响。结果:红果参叶中总黄酮的最佳提取工艺条件为:85%(体积分数)的乙醇作为提取溶剂、提取时间10 min、料液比1∶30(g/mL)。在此条件下,总黄酮提取率可达4.76%。结论:乙醇超声法可用于红果参叶中总黄酮的提取,其中料液比对提取率的影响最大。     

杜梨叶黄酮的提取工艺研究及其初步定性分析

目的:优化杜梨叶总黄酮提取的工艺及其初步定性分析.方法:研究了浸提温度、乙醇浓度、提取时间、料液比等因素对杜梨叶中黄酮类化合物提取效果的影响,和正交试验进行优化,所得结果采用方差分析.采用颜色反应的方法进行杜梨叶中黄酮的初步定性分析.结果:确定了最佳单因素水平,正交实验确定了以乙醇为浸提荆的最佳提取工艺条件为:乙醇体积分数60%,料液比1:22,温度80℃,浸提时间1h,在此条件下黄酮含量为5.03%.结论:杜梨叶中含黄酮类化合物,颜色反应试验表明,其成分主要集中在黄酮醇类和二氢黄酮类.     

葡萄叶中总黄酮的提取工艺研究

目的：从葡萄叶中提取总黄酮。方法：采用正交试验法研究葡萄叶总黄酮的最佳提取工艺条件,考察了乙醇浓度、回流温度、回流时间及料液比四因素对葡萄叶总黄酮提取率的影响。结果：确立了葡萄叶总黄酮最佳提取条件为：45％的乙醇为溶剂、液料比为1：40、提取温度为60％、提取时间2h,在最佳工艺条件下葡萄叶总黄酮含量为5．329mg／g。     

超声波法提取玉兰花总黄酮的工艺研究

目的:超声波优化玉兰花总黄酮提取工艺。方法:以芦丁为对照,在单因素试验的基础上以乙醇体积分数、料液比、温度、超声时间、超声功率为考察因素,利用紫外可见分光光度计测定总黄酮吸光度,以总黄酮含量为评价指标,采用L16(45)正交实验优化提取工艺。结果:玉兰花总黄酮的最佳提取工艺为:70%乙醇溶液为提取溶剂,采用液固比10 m L/g,在180 W超声功率和35℃下超声提取30 min。结论:实验表明超声波提取玉兰花工艺方法简单、合理、稳定且可行,为玉兰花的进一步开发利用提供了实验基础。     

老鸦瓣叶中黄酮成份的提取及初步鉴定

以老鸦瓣干燥叶为原料,采用超声波提取老鸦瓣干燥叶的总黄酮,紫外分光光度法测定含量。在单因素实验中,分别研究了超声时间、料液比、超声功率、乙醇体积分数等因素对提取率的影响,在单因素实验的基础上进行了正交试验,得出最佳工艺:乙醇体积分数60%、超声时间60 min、料液比1∶30、超声功率80 W,在最佳工艺条件下,老鸦瓣干燥叶的总黄酮为6.28%。并经HPLC对提取的黄酮类物质进行初步鉴定,结果显示,该样品包含儿茶素、芦丁、杨梅素、槲皮素、山奈酚、异鼠李素等黄酮类物质,为老鸦瓣资源的合理化应用提供研究基础与依据。     

Box-Behnken设计优化甘草浸膏中甘草苷的超声提取

以新疆甘草浸膏为原料,利用Box-Behnken设计优化超声提取甘草浸膏中甘草苷的工艺。在单因素试验的基础上,利用响应面法考察固液比、超声时间和乙醇体积分数对甘草苷含量的影响,优化提取工艺,得到最佳工艺条件:固液比2.5 g/L、超声时间24 min、乙醇体积分数59%,甘草苷一次提取含量达到0.832%。此研究对甘草浸膏的综合利用以及产业化发展提供了科学依据。     

Investigation of the mechanism of temperature sensitivity of the electroreceptors of ampullae of lorenzini

In experiments on Black Sea skates (Raja clavata), the potential of the receptor epithelium of the ampullae of Lorenzini and spike activity of single nerve fibers connected to them were investigated during electrical and temperature stimulation. Usually the potential within the canal was between 0 and –2 mV, and the input resistance of the ampulla 250–400 k. Heating of the region of the receptor epithelium was accompanied by a negative wave of potential, an increase in input resistance, and inhibition of spike activity. With worsening of the animal's condition the transepithelial potential became positive (up to +10 mV) but the input resistance of the ampulla during stimulation with a positive current was nonlinear in some cases: a regenerative spike of positive polarity appeared in the channel. During heating, the spike response was sometimes reversed in sign. It is suggested that fluctuations of the transepithelial potential and spike responses to temperature stimulation reflect changes in the potential difference on the basal membrane of the receptor cells, which is described by a relationship of the Nernst's or Goldman's equation type.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. I. M. Sechenov, Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. Pacific Institute of Oceanology, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Neirofiziologiya, Vol. 12, No. 1, pp. 67–74, January–February, 1980.     

Principles of organization and evolution of systems of regulation of functions

Evolution of living organisms is closely connected with evolution of structure of the system of regulations and its mechanisms. The functional ground of regulations is chemical signalization. As early as in unicellular organisms there is a set of signal mechanisms providing their life activity and orientation in space and time. Subsequent evolution of ways of chemical signalization followed the way of development of delivery pathways of chemical signal and development of mechanisms of its regulation. The mechanism of chemical regulation of the signal interaction is discussed by the example of the specialized system of transduction of signal from neuron to neuron, of effect of hormone on the epithelial cell and modulation of this effect. These mechanisms are considered as the most important ways of the fine and precise adaptation of chemical signalization underlying functioning of physiological systems and organs of the living organism