Clevenger法提取草果精油的化学组成及清除NaNO2能力

采用Clevenger法提取草果精油,以1.87%的平均得油率获得精油,用GC-MS联机对精油进行了成分分析,检测出38种成分,解析鉴定了占总成分98.393%的32个成分。主要成分1,8-桉树脑占40.891%(相对含量,以下同),α-水芹烯9.769%,2-异丙基苯甲醛6.988%。测定精油清除NaNO2能力结果可知:当精油用量为0.15～0.45 mL时,清除率为68.22%～81.40%,大于对照物Vc(57.12%～78.16%)和BHT(14.64%～18.66%)(精油和对照物浓度10 mg/mL)。     

小花假泽兰精油超临界CO_2提取工艺及其成分和抑菌活性研究

采用正交试验法研究超临界CO_2萃取法提取小花假泽兰精油的提取条件,采用GC-MS法分析测定精油的化学成分,并初步测定精油的抑菌效果.结果表明:超临界CO_2萃取小花假泽兰精油的较佳工艺条件为:采用先静态后动态的萃取方式,静态萃取时间20 min,动态萃取条件为萃取温度55℃,萃取压力35 Mpa,CO_2体积为40 mL/g,CO_2 流速为0.5～1.0 mL/min;从超临界CO_2萃取的小花假泽兰精油中鉴定了64种成分,占精油总量的79.80%,主要有萜类、醇类、脂肪酸、酯类、甾体类等;生物测定结果表明,超临界CO_2萃取物对小麦赤霉病菌和小麦纹枯病菌菌丝生长的EC_(50)分别为119.55 mg/L和78.27 mg/L. 果.结果表明:超临界CO_2萃取小花假泽兰精油的较佳工艺条件为:采用先静态后动态的萃取方式,静态萃取时间20 min,动态萃取条件为萃取温度55℃,萃取压力35 MPa,CO_2体积为40 mL/g,CO_2 流速为0.5～1.0 mL/min;从超临界CO2萃取的小花假泽兰精油中鉴定了64种成分,占精油总量的79.80%,主要有萜类、醇类、脂肪酸、酯类、甾体类等;生物测定结果表 ,超临界CO_2萃取物对     

木鳖子提取物对朱砂叶螨的触杀活性

测定了木鳖子提取物对朱砂叶螨的触杀活性。用甲醇、氯仿、石油醚3种不同极性的溶剂提取,石油醚提取率最高为30.79%,且对朱砂叶螨成螨和卵的触杀活性均高于其他两种溶剂的提取物,24 h校正死亡率分别为77.52%和72.04%。用甲醇对石油醚提取物萃取,发现甲醇萃取物活性明显高于石油醚部分,对成螨和卵处理24 h后的校正死亡率分别为89.60%和74.65%,产卵抑制率为62.74%,驱避率为58.23%。柱层析对甲醇萃取物进行分离得到10种组分,组分5活性最高,浓度为2 mg/mL时,24 h校正死亡率为86.15%。用薄层层析和气相色谱质谱联用仪分别检测组分5纯度和主成分,初步确定活性成分为α-菠菜甾醇。     

芫荽茎叶精油的消除DPPH自由基作用

用GC-MS对超声波法提取的芫荽茎叶精油成分进行了分析,检测出154个成分,解析出70种物质,占精油93．643％,含量最多的是酯类化合物47．569％,其次为饱和与非饱和烃类化合物19．897％,醛类化合物和醇类化合物含量分别为13．406％,12．595％。探讨了精油对DPPH的清除作用,结果显示,用超声波萃取法获得的精油对DPPH自由基（1,1-diphenyl-2-picrylhydrazyl）具有一定的消除作用,最高消除率62．9％,水蒸汽蒸馏法获得的芫荽茎叶精油的DPPH自由基清除率最大为84．2％。     

响应面法优化超临界CO2萃取茉莉花蕾精油及抗氧化活性的研究

为研究超临界CO2萃取茉莉花蕾获得精油的最佳工艺及抗氧化活性,实现资源的综合利用。实验考察了夹带剂用量、原料颗粒大小、萃取压力、萃取温度和动态萃取时间对茉莉精油产率的影响,进一步以响应面实验设计优化挥发油的提取工艺参数,以GC-MS分析挥发油组成及相对含量,并测定精油清除DPPH自由基及还原铁离子能力。结果表明,最佳工艺参数为:夹带剂乙醇用量为0.2mL/g,花粉颗粒为40目,萃取压力20MPa,萃取温度46℃,动态萃取时间1.6h。在此条件下茉莉精油的产率为13.67%,远高于同时蒸馏萃取法(2.87%)和超声辅助提取(2.45%)。超临界萃取精油的主要香气成分与茉莉鲜花基本一致,并且具有较好的清除自由基和还原铁离子能力。实验证明超临界萃取技术提取茉莉花蕾得到茉莉精油品质高,可为其资源综合利用提供参考。     

永州香樟叶精油的提取及其季节含量变化

本实验以永州香樟叶为原料,优化了超临界CO2萃取制备香樟叶精油的工艺条件。结果显示,超临界CO_2萃取香樟叶精油的最适工艺条件为:CO_2流量20 L/h,萃取压力18 MPa,萃取温度46℃,萃取时间1.6 h,在此工艺条件下永州香樟叶精油萃取率可达到98.37%,高出索氏提取法42.97%,高出水蒸气蒸馏法26.69%。当加入0.6%CO_2流量的乙醇作为夹带剂萃取时间缩短了26 min,可进一步节省能耗。同时研究了永州香樟叶精油在一年内各季度的变化规律,发现夏秋两季精油含量水平较高,而春冬两季较少,在1月含量达到最低。     

2种方法提取绒毛香茶菜精油成分及体外抗氧化能力的比较研究

分别采用微波辅助水蒸气蒸馏法和超声波辅助水蒸气蒸馏法,从新鲜的绒毛香茶菜叶片中提取精油,用GC-MS对精油化学成分进行测定,且对比了2种不同方法提取的精油对DPPH自由基、ABTS自由基、超氧阴离子自由基的清除能力。结果表明:微波辅助水蒸气蒸馏法优于超声波辅助水蒸气蒸馏法,提取率达到0.56%。绒毛香茶菜精油主要成分为烯烃类及酮类,2种方法提取的绒毛香茶菜精油成分中,4-羟基-4-甲基-2-戊酮最多(相对含量在23.23%～42.53%之间),其次是α-萜品烯、萜品油烯、双戊烯和D-柠檬烯。在不同的抗氧化能力评价体系中证实,2种方法提取的绒毛香茶菜精油在(200～1 000)μg/mL浓度梯度范围内均有较强的抗氧化活性,且与精油浓度梯度成正相关。综上所述,2种提取法所得绒毛香茶菜精油的提取率、成分、含量及抗氧化活性等方面均存在一定差异,为绒毛香茶菜精油的深入研究提供了理论基础。     

7种不同提取方式对香露兜挥发性成分的影响

为了解不同提取方式对香露兜挥发性成分的影响,以采自海南兴隆的香露兜成熟鲜叶为研究对象,采用100%甲醇蒸馏法、75%乙醇蒸馏法、100%乙醇蒸馏法、75%乙醇超声波辅助法、100%乙醇超声波辅助法、75%乙醇浸提法和100%乙醇浸提法7种不同方式进行提取,利用气相色谱-质谱法(GC-MS)测定各提取物的挥发性成分,并结合主成分分析(PCA)和相关分析(CA)对其组成和含量差异进行比较分析。结果表明,7种不同提取方式共鉴定出52种挥发性成分,主要由酯类、醇类、酮类、烯烃类、吡咯类物质组成,100%甲醇蒸馏法未检测出关键特征香气物质2-乙酰-1-吡咯啉(2-AP),其余6种方式提取物均有检出,含量变幅为1.21～37.48μg/g;7种香露兜提取物相关性系数平均值为34.80%±7.20%,PCA分析将7种提取方式分为3组:75%、100%乙醇超声波辅助提取法和75%、100%乙醇浸提法主要挥发性成分为叶绿醇、角鲨烯、3-羟基-2-丁酮、棕榈酸乙酯、羟基丙酮、3-甲基-2-(5H)-呋喃酮和2-AP,75%和100%乙醇蒸馏提取法主要挥发性成分为硬脂酸甲酯、2-AP、(E)-7-四癸醇和棕榈酸甲酯,100%甲醇蒸馏提取法主要挥发性成分为(Z)-十六烯酸甲酯、苯乙烯、十四酸甲酯、十五碳酸甲酯。由此说明,香露兜7种不同方式提取物3个组间挥发性成分的组成和含量存在差异,这为香露兜产品精深加工提供了理论依据。     

干姜超临界CO2萃取与水蒸气蒸馏工艺比较研究

目的：比较干姜的超临界CO2萃取与水蒸气蒸馏两种工艺的差别,为其在复方制剂中的应用提供工艺设计参考。方法：分别用超临界CO2萃取和水蒸气蒸馏处理干姜药材,采用GC、TLC对产物进行分析比较。结果：超临界CO2萃取产物得率为8．0％,水蒸气蒸馏得率为0．2％,GC、TLC显示超临界CO2萃取物比水蒸气蒸馏样品有较多的成分。结论：干姜的超临界CO2萃取工艺较水蒸汽蒸馏工艺的产物量高,成分较多。     

大蒜化学成分的气-质联用分析

本文采用环己烷、乙酸乙酯和正丁醇对大蒜（Allium sativum L.）新鲜鳞茎的95%乙醇提取物进行萃取,并与水蒸气蒸馏法提取的挥发油成分进行比较,用GC-MS对其成分进行定性和定量分析.在环己烷萃取物中共检出112个成分,鉴定了38个化合物,占环己烷萃取物总量的80.08%;在乙酸乙酯萃取物中检出86个成分,鉴定了26个化合物,占乙酸乙酯萃取物总量的56.70%;在正丁醇萃取物中未检出挥发性成分.在水蒸气蒸馏法提取的挥发油中共检出109个成分,鉴定了29个化合物,占挥发油总量的83.58%.大蒜95%乙醇提取物的环己烷和乙酸乙酯萃取物及大蒜挥发油中皆以含硫化合物为主.在环己烷和乙酸乙酯萃取物中,阿霍烯的含量分别为生药的0.00395%和0.00145%,大蒜中阿霍烯含量达0.00540%.     

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