侧柏叶活性成分研究进展

侧柏叶（Cacumen Platycladi）中主要含有黄酮、挥发油、鞣质等活性成分,具有多种多样的药理作用,文章介绍了侧柏叶几种活性成分的研究进展,为充分挖掘侧柏叶产品的药用价值及深层次开发高附加值产品奠定了基础,具有重大现实意义.     

侧柏叶总黄酮提取工艺研究进展

侧柏叶含有黄酮、多酚和多糖等成分,其中黄酮类类成分含量较高,具有广泛的药理活性。侧柏叶总黄酮具有抗炎、抗癌、降尿酸等多种活性。本文对侧柏叶总黄酮的提取技术进行了综述,为侧柏叶的进一步开发利提供依据。     

侧柏叶挥发油提取工艺及其抑菌活性研究

采用水蒸气蒸馏法提取侧柏叶挥发油,以减重法测定挥发油质量,并用薄层色谱法及气相色谱法进行成分分析,通过测量侧柏叶挥发油的抑菌圈大小考察其抑菌活性.正交实验确定侧柏叶挥发油的最佳提取工艺条件为:侧柏叶粉碎度20～30目,加6倍量水,浸泡时间12 h,提取时间5 h;侧柏叶挥发油对金黄色葡萄球菌、四联球菌、大肠杆菌和产气杆菌均有明显的抑制作用,对枯草杆菌的抑菌作用不明显.     

侧柏叶有效成分提取及酪氨酸酶活性影响评价

目的：研究侧柏叶有效成分总黄酮的最佳提取工艺,并评价有效提取成分对酪氨酸酶活性的影响。方法：采用单因素试验、正交试验考察了提取过程中各因素对侧柏叶总黄酮含量的影响;采用蘑菇酪氨酸酶多巴速率氧化法考察提取成分对酪氨酸酶活性的影响。结果：本实验确定最优的提取工艺为90%乙醇作为提取液,按照1∶15的料液比（g∶mL）,以70℃的超声温度进行提取,超声时间为60 min,此条件下总黄铜提取量为1.394 mg/g。0.5 g/mL乙酸乙酯提取物的激活率最小,为-211.68%±2.42%;0.5 g/mL石油醚提取物的激活率最大,为20.30%±1.32%。结论：本研究确定了侧柏叶有效成分提取的最佳工艺,经过对有效成分活性测试可知,乙醇粗提取物和乙酸乙酯提取物对酪氨酸酶的活性有抑制作用且随着浓度升高而升高,石油醚提取物低浓度有抑制作用,高浓度有激活作用。     

薄荷活性成分及其提取技术的研究进展

薄荷叶中主要含有挥发油、黄酮类、酚酸类、醌类、萜类、氨基酸和微量元素等成分,具有多种药理作用.本文详细介绍了薄荷的活性成分和药理作用,以及薄荷黄酮及多酚的提取技术的研究进展,可为充分挖掘薄荷产品的药用价值及深层次开发高附加值产品,提供文献参考.     

菊花脑活性成分及其提取技术研究进展

菊花脑作为一种常见的野菜,含有蛋白质、脂肪、纤维素、维生素和黄酮类化合物、挥发油等多种活性成分,并拥有多种药理作用。文章主要介绍目前菊花脑主要活性成分及提取方法的研究进展,同时为挖掘菊花脑产品的药用价值和开发研究更深层次地高附加值产品铺设道路,契合市场发展规律,具有较高的现实意义。     

侧柏叶有效成分提取过程研究

研究了侧柏叶有效成分酶法提取及乙醇－水混合溶剂提取过程。用测定电导率及标定有效成分含量方法反映提取规律。对提取过程中的温度、ｐＨ值、酶用量、提取时间、乙醇浓度及侧柏叶粒度等工艺条件进行了实验研究,得到优化的提取条件。提出在理论上用溶解度参数法选择提取剂及其浓度,实验结果证实与理论一致。     

茉莉花活性成分分析及提取技术研究进展

茉莉花富含多糖类、黄酮类及挥发油等活性成分,具有一定的药用价值。本文综述了茉莉花的几种主要活性成分及其提取技术,并对本领域后续发展进行了展望,旨在为茉莉花活性成分的理论研究与应用价值提供依据。     

胆碱/谷氨酸离子液体微波辅助提取栀子活性成分的研究

研究了[胆碱][谷氨酸]离子液体([Ch][Glu]IL)水溶液提取栀子活性成分的方法。以栀子黄色素、绿原酸、栀子苷三者收率为考察指标,用响应面优化了微波辅助提取栀子活性成分的条件。最佳条件为:[胆碱][谷氨酸]离子液体水浓度1. 4%、液料比25. 5 m L/g、微波功率320 W、微波处理时间305 s。在此条件下,栀子黄色素、绿原酸、栀子苷的收率可达49. 58、17. 23、71. 82 mg/g。[Ch][Glu]IL水溶液提取栀子活性成分具有时间短、效率高、环境友好等优点,为栀子活性成分的获得提供了新方法。     

八角中黄酮提取及其抗氧化抑菌活性研究进展

黄酮是八角的功能活性成分之一,具有抗氧化抑菌活性,在医药、食品、卫生和保健品等领域具有广泛应用前景。开发应用八角黄酮对发展八角产业有重要的实际意义。本文概述我国八角黄酮提取纯化工艺及抗氧化抑菌活性研究进展,为八角黄酮提取纯化及其抗氧化抑菌活性的进一步研究提供参考。     

The reaction of methyl vinyl ketone with alpha- and beta-eleostearic acids

Summary Methyl vinyl ketone was found to be an active dienophile for the modification of the eleostearate One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.     

异丁烷脱氢Pt系催化剂研究进展

介绍异丁烷脱氢制备异丁烯Pt系催化剂的研究进展,表明催化剂的活性中心、载体和助剂对异丁烷脱氢反应性能影响较大。催化剂活性中心的积炭覆盖和烧结是催化剂失活的直接原因;载体的酸性有助于调变积炭的形成速率,而活性中心与助剂的交互作用可促使积炭的表面迁移;活性中心与载体的交互作用有利于减少活性中心的烧结。     

分离用金属陶瓷复合膜及研究进展

金属陶瓷复合膜是由金属膜及表面陶瓷活性膜层复合而成,综述金属膜制备方法及金属膜表面溶胶凝胶法制备陶瓷活性层膜制备技术,为金属陶瓷复合膜制备提供理论意义。论述国内外金属陶瓷复合膜研究进展,对金属陶瓷复合膜制备工艺技术及应用范围展望。     

穿山龙水溶性有效成分的研究概况

对穿山龙水溶性有效成分的作用、研究进展等方面进行了系统介绍,并对其发展前景进行了分析展望。     

Aggregation pheromones of the flat grain beetle,Cryptolestes pusillus (Coleoptera: Cucujidae)

Aggregation pheromones were isolated fromCryptolestes pusillus (Schönherr), a coleopteran pest of stored products. Porapak Q-captured beetle and frass volatiles were fractionated by preparative gas-liquid chromatography. The fractions were bioassayed with an arena olfactometer and/or with a two-choice, pitfall olfactometer. Three biologically active, male-produced compounds eliciting aggregation behavior from adultC. pusillus were isolated and identified by spectroscopic methods as (Z)-3-dodecenolide (I), (Z)-5-tetradecen-13-olide (II), and (Z,Z)-3,6-dodecadienolide (III). Compound I was the major volatile produced and was active alone. Compound II was not active alone, but synergized the response to I. Compound III was active alone at higher concentrations, but did not significantly increase the response when added to the most active mixture of I and II, and so it is probably not part of the aggregation pheromone. Pheromone production increased dramatically when the insects were aerated on a food source.Research supported in part by the Natural Sciences and Engineering Research Council of Canada, Operating Grants A3881 and A3785, Strategic Grant 60958, and a Graduate Scholarship to J. G. Millar.     

Thermal rearrangement of sulfated tallow alkanolamides

A study of reaction variables in the sulfation of tallow alkanolamides revealed that a molecular rearrangement to aminoester occurs as a result of prolonged heating in the unneutralized state. Heating sulfated isopropanolamide for 4 hr at 60 C resulted in a 60% loss of active ingredient. The sulfated diglycolamide heated at 60 C for 12 hr suffered a loss of 22% active ingredient. A 50:50 mixture of these sulfated alkanolamides heated for 12 hr at 40 C incurred no loss of active ingredient content, whereas at 60 C a 40% loss of active ingredient was observed. Thus, careful temperature control and rapid neutralization after sulfation are required to obtain sulfated alkanolamides with a high percentage of active ingredient. Agricultural Research, Science and Education Administration, USDA.     

Soap—Based detergent formulations: XXV. Synthesis and surface active properties of higher molecular weight betaine lime soap dispersants

A series of surface active betaines have been prepared via the quaternization of a tertiary amine with drolysis. The betaines possessed a hydrophobic (C₁₂-C₁₆) alkyl side chain, and the anionic and cationic sites were separated by one, two, or three methylene groups or a benzyl group. The betaines were more water soluble and were poorer lime soap dispersants than analogous sulfobetaines. Detergency of most soap-based detergent formulations containing the betaine lime soap dispersants was good and generally close to that of a commercial control detergent containing 50% sodium tripolyphosphate in screening tests conducted in water of 300 ppm hardness. Fats and Proteins Research Foundation fellow stationed at Eastern Regional Research Center. Federal Research, Science and Education Administration, U.S. Department of Agriculture.     

Synthetic detergents from animal fats. Disodium alpha-sulfopalmitate and sodium oleyl sulfate

Summary Disodium α-sulfopalmitate and homologous compounds were prepared by sulfonation of the fat acid with liquid sulfur trioxide. Sodium oleyl sulfate was prepared in an estimated 95% purity by sulfation of oleyl alcohol with pyridine-sulfur trioxide. The solubility, surface tension, wetting, foaming, and detergent properties of these and related compounds were measured. Disodium α-sulfopalmitate is potentially inexpensive, has adequate surface active properties, is a good detergent in hard and soft water, but has limited solubility at room temperature (0.25% at 25°C.). The lauric and myristic homologs are less surface active, but more soluble. Disodium α-sulfostearate is less soluble. Sodium oleyl sulfate has excellent solubility, and surface active properties and is an excellent detergent in soft water. It is not quite so efficient in hard water although no insoluble calcium salts are formed. The future of the two compounds will depend upon successful formulation with builders or combinations with soap or other detergents. Report of a study in which certain phases were made under the Research and Marketing Act of 1946. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, United States Department of Agriculture. Presented at the meeting of the American Oil Chemists’ Society, Chicago, Ill., in October 1951.     

FePO Catalysts for the Selective Oxidative Dehydrogenation of Isobutyric Acid into Methacrylic Acid

This review presents the iron phosphorus oxides used as catalysts for isobutyric acid oxidative dehydrogenation. Research on this catalytic system has been developed in the last decade and many publications have been devoted to this reaction, as it can be a step in a new process of production of methyl methacrylate. We emphasize particularly the nature of the active phase, the active centers, and the role of water and promoters. The mechanistic aspects of the reaction, which corresponds to an extension of the Mars and van Krevelen mechanism with a special role of water partial pressure, are discussed.