华根霉全细胞脂肪酶催化合成生物柴油

比较了5种不同商品化脂肪酶和自制的华根霉CCTCCM201021全细胞脂肪酶(RCL)催化油脂合成生物柴油的转化效果,结果表明,RCL能有效应用于无溶剂体系催化合成生物柴油.在无溶剂体系中对该酶催化生物柴油的转酯化反应工艺进行优化,考察了甲醇用量、体系含水量、酶的添加量和反应温度对生物柴油收率的影响,使生物柴油最终收率大于86.0%.在有机溶剂体系中选择不同有机溶剂作为助溶剂进行转酯化反应,发现logP值在4.0～4.5的有机溶剂具有较好的转化效果.其中以正庚烷为助溶剂的转酯化反应具有最高的生物柴油收率86.7%.在无溶剂体系中RCL催化转化油酸和模拟高酸价油脂合成脂肪酸甲酯的研究表明,该酶具有很好的催化合成生物柴油的潜力.     

不同溶剂中酶催化合成油酸酯研究初探

对几种非水溶剂中脂肪酶催化合成油酸酯 (油酸乙酯、油酸正辛酯和油酸油酯 )进行了初步考察。结果表明 ,在环己烷、正庚烷和甲苯等有机溶剂中 ,上述酯化反应都有很高的转化率 ;在所考察的实验条件下 ,超临界CO2 中反应的转化率略比上述有机溶剂中的低 ,但该结果已初步显示以超临界CO2 替代有机溶剂合成油酸酯具有很大的应用潜力。     

混合溶剂系统中固定化脂肪酶对酮基布洛芬的催化酯化反应

以硅藻土吸附的脂肪酶为催化剂,对外消旋酮基布洛芬[2-(3-苯甲酰苯基)丙酸]进行对映选择性酯化反应;考察了不同的脂肪酶制剂,固定化时所加缓冲液的体积与pH值,酰基受体(醇)的种类以及混合溶剂系统的组成等因素对酶活性的影响.结果表明,在所考察的7种脂肪酶中,以LipaseOF的酪化活性最高;用硅藻土吸附固定化酶时,缓冲溶液的最适pH为7.0左右,每克酶粉加1.0mL缓冲溶液为最佳;固定化酶催化酯化的活性比游离的脂肪酶高.在酮基布洛芬与不同酰基受体(醇)的酶促酯化反应中,以丙醇的反应速度为最快.在由一种主溶剂与一种助溶剂组成的混合溶剂系统中,酶促酯化的速度要比在单一的主溶剂或助溶剂系统中快.当以1gP值较大的环己烷或异辛烷等为主溶剂,甲苯为助溶剂时,脂肪酶催化酮基布洛芬酯化反应的活性最高.     

无溶剂体系中固定化脂肪酶Candida sp. 99-125催化合成油酸低碳醇酯

采用固定化脂肪酶Candida sp.99-125在无溶剂体系中催化合成油酸低碳醇酯,考察了加酶量、温度、酸醇摩尔比和醇结构对油酸酯化率的影响。结果表明,加酶量为底物质量的3%,最适温度为20℃,酸与醇摩尔比为1∶1,甲醇对该酶有一定的毒性,由于空间位阻效应,该酶对伯醇具有高选择性,对仲醇、叔醇的选择性低,且对长链脂肪酸催化活性高,对带支链的多元酸、多元醇活性低。该酶重复使用5次,酶活性基本没有降低。与传统的化学法相比,用该酶催化合成酯类化合物的色泽更浅。     

微乳液中脂肪酶和含明胶的微乳液凝胶中固定化脂肪酶的催化特性

在双2-乙基己基琥珀酸酯磺酸钠(AOT)油包水微乳液中Calytical脂肪酶催化月桂酸和戊醇的酯化反应动力学研究表明,反应符合乒乓(BiBi)机制.表观速率常数k_m酸=0.13518mol/L,k_m醇=0.22423mol/L,最大反应速度v_max=1.3873×10^-5mol/(L·min·mg).将该脂肪酶固定于含明胶的微乳液凝胶(MBGs)中,制得固定化脂肪酶,含酶MBGs在非极性溶剂中可作为固相催化剂,并研究了其在辛烷中催化酯化的性能.所制得的含酶MBGs物理稳定性好,重复利用10次以上,其转化率仍达初始转化率的90%.     

水/有机溶剂双相中杏仁醇腈酶促不对称合成(R)-苯乙氰醇

 研究了水／有机溶剂双相中来源于杏仁的（R）－醇腈酶催化苯\r\n甲醛与HCN不对称合成（R）－苯乙氰醇,系统探讨了有机溶剂、水相与\r\n有机溶剂相体积比、水相pH值和反应温度对反应速度、转化率和产物光\r\n学纯度的影响．结果表明,上述因素对醇腈酶促不对称合成（R）－苯\r\n乙氰醇反应均有显著影响．异丙醚为该反应最好的有机溶剂,水相与有\r\n机溶剂相体积比以1／2为宜,适宜的pH值为3．4,最佳反应温度为0～\r\n5℃．在该优化反应条件下,反应转化率和产物的光学纯度均高达99％\r\n以上．     

酶促合成油酸香茅醇酯的超临界连续反应-分离过程

将固定床动态酶促反应过程和超临界二氧化碳萃取分离过程相耦合,设计并建立了一套超临界相反应分离一体化的实验装置。在该装置上初步考察了反应压力和温度对脂肪酶催化油酸甲酯和外消旋香茅醇酯交换反应的影响。结果表明,我们所建立的反应装置能有效地实现反应分离一体化过程;当体系压力接近二氧化碳的临界压力时反应速率最高;9MPa压力下反应温度为328K时反应转化率最高,而在14MPa压力下反应转化率在308K～328K之间随着温度的升高而增大。     

无溶剂体系脂肪酶催化合成阿魏酸油醇酯

对无溶剂体系中阿魏酸的转酯化疏水改性进行了研究,确立了减压反应器(0.001 MPa)中Novozym 435脂肪酶催化阿魏酸乙酯和油醇进行转酯化反应合成新型抗氧化剂阿魏酸油醇酯的方法.发现水活度(aw)明显影响转酯反应,阿魏酸油醇酯产率在aw＜0.01-0.75范围内随着水活度的增加而降低,推测底物阿魏酸乙酯和产物阿...     

有机相中α-氰基-3-苯氧基苄醇乙酯的酶促醇解反应

研究了有机相中脂肪酶催化α-氰基-3-苯氧基苄醇乙酯的醇解化反应。制备α -氰基-3-苯氧基苄醇。考察了酶、溶剂、醇、醇用量、溶剂水含量以及底物浓度等 因素对反应的影响，结果表明Novozym435脂肪酶催化活性最高，经实验确定的最佳 条件为：脱水甲苯为溶剂，正辛醇为酰基受体，正辛醇、酯的摩尔比为1.5:1，酶 量为8 mg/mL时的最佳底物浓度为108.13 mmol/L，在上述条件下反应30 h酯的转化 率 > 96%。     

无溶剂体系中酶法合成2-辛基十二烷醇酯

考察了无溶剂反应体系下脂脂酶催化直接酯化合成２－辛基十二烷醇酯。在ｍｏｌ醇：ｍｏｌ酸＝１．６：１,反应温度６０℃,脂肪酶添加量４％,反应时间１０ｈ的最佳条件下,酯化率可达９４．８％。     

The Petroleum Industry Surfactants Synthesized from Fish Oils

Biodegradable surfactants for the petroleum industry have been synthesized by the sulfurization of fish oils. A qualitative composition analysis of surfactants was conducted by FTIR spectroscopy that showed the presence of sulfonic acid groups in the samples. Previously, several samples of the technical fish oils (fish processing waste) have been studied with regard to their use for the synthesis of biodegradable surfactants. It has been shown by gas–liquid chromatography, FTIR spectroscopy, high-performance liquid chromatography, and mass spectrometry method that samples under study contain a large amount of saturated and nonsaturated fatty acids with hydrocarbon radicals comprising from 16 to 22 carbon atoms. The results reveal that the concentration of oleic acid approaches to 15 wt%. Fish oils with a high content of free fatty acids were used as the basis for the synthesis of technical, environmentally friendly surfactants that can be applied in the petroleum industry.     

尼古丁是脂肪酶的反竞争抑止剂的实验研究

希望明确尼古丁对脂肪酶活性是否有抑止作用,用于解释医学已有统计数据：吸烟的人体重普遍较轻,而戒烟后体重会有回升．用三油酸甘油酯为底物,在加入尼古丁前后,检测脂肪酶活性变化．结果表明：脂肪酶在人体外仍有活性,而且尼古丁是脂肪酶反竞争性抑止剂．在脂肪酶浓度为7mg／mL时,抑止程度达50％．     

1,3-丙二醇油酸双酯的合成

以对甲苯磺酸为催化剂,油酸和1,3-丙二醇为原料合成了1,3-丙二醇油酸双酯。最佳反应条件为:油酸60 mmol,n(油酸)∶n(丙二醇)=2.1,催化剂对甲苯磺酸的用量为油酸质量的3.5%,带水剂甲苯20 mL,于160℃反应1 h。在优化反应条件下,酯化率98%,收率77%。     

Lamellar liquid crystal polymerization of sodium oleate/oleic acid/octadiene/water system

In the lamellar liquid crystallization (LLC) phase of NaOL/ OLA/H2O system, the small angle X-ray diffraction measurements show that the oleic acid is solubilized in the oil layer at first and then into the amphiphile layer. The octadiene added is also located partly in the oil layer and partly in the amphiphile layer in the LLC. With the addition of octadiene as cross-Unking agent, the LLC phase of NaOL/OIA/H2O system was polymerized under the initiation of AIBN with the protection of pure nitrogen at 60℃. Most of the double bond absorption of the monomers in IR spectra disappeared after polymerization. The polymerization takes place not only in the middle of the amphiphile layer between the double bonds of NaOL or OLA and those of octadiene, but also in the oil layer of LLC between the double bonds of OLA and those of octadiene. Interlayer spacing measurements on the copolymer proved d values decreased by about 1-2 nm compared with those of the corresponding system before the polymerization, indicati     

Adsorption of oleic acid and triolein onto various minerals and surface treated minerals

A systematic investigation of the adsorption of oleic acid was under-taken with various minerals and surface treated minerals, viz., kaolinite, treated kaolinites, montmorillonites, talcs, gibbsites, calcites and a treated calcite. Adsorption onto kaolinite, two of the treated kaolinites (amine and MgSiO₃ treated), talcs and gibbsites was well correlated by the Langmuir model, while adsorption on the treated calcite was well correlated by the Freundlich model. Adsorption on a cationic polymer-treated kaolinite was explained in terms of a cooperative mechanism. Adsorption onto montmorillonites was explained in terms of a penetrative mechanism involving exchangeable cations.Oleic acid adsorption was compared with triolein adsorption on one of the montmorillonites, two adsorbents produced by the surface treatment of this montmorillonite, and one of the talcs. The triolein adsorption of the montmorillonite was considerably less than its oleic acid adsorption, and was explained in terms of a cooperative mechanism. Triolein adsorption of the treated montmorillonites, and the talc was well correlated by the Langmuir model. Larger amounts of triolein were taken up by the treated montmorillonites than by the untreated montmorillonite. The triolein adsorption of the talc was greater than its oleic acid adsorption.     

The promoting effect of organotin compounds upon peroxidation of oleic acid

The effect of the organotin compounds R _nSnCl_4?n (n = 1–3; where R = Me, Et, n‐Bu and Ph) upon oleic ((Z)‐9‐octadecenoic) acid oxidation by dioxygen has been studied at 25, 37, 65, and 95 °C. The promoting effect of organotins upon the formation of oleic acid hydroperoxides is temperature dependent and is at a maximum at a temperature close to the physiological one, but the impact of organotins upon oleic acid peroxidation decreases in the presence of 2,6‐di‐tert‐butylphenol. The role of organic free radicals derived from the Sn? C bond cleavage in the oxidation of oleic acid is discussed. Copyright © 2002 John Wiley & Sons, Ltd.     

A Mechanistic Study of the Multiple Roles of Oleic Acid in the Oil-Phase Synthesis of Pt Nanocrystals

Oleic acid (OAc) is commonly used as a surfactant and/or solvent for the oil-phase synthesis of metal nanocrystals but its explicit roles are yet to be resolved. Here, we report a systematic study of this problem by focusing on a synthesis that simply involves heating of Pt(acac)₂ in OAc for the generation of Pt nanocrystals. When heated at 80 °C, the ligand exchange between Pt(acac)₂ and OAc leads to the formation of a Pt^II–oleate complex that serves as the actual precursor to Pt atoms. Upon increasing the temperature to 120 °C, the decarbonylation of OAc produces CO, which can act as a reducing agent for the generation of Pt atoms and thus formation of nuclei. Afterwards, several catalytic reactions can take place on the surface of the Pt nuclei to produce more CO, which also serves as a capping agent for the formation of Pt nanocrystals enclosed by {100} facets. The emergence of Pt nanocrystals further promotes the autocatalytic surface reduction of Pt^II precursor to enable the continuation of growth. This work not only elucidates the critical roles of OAc at different stages in a synthesis of Pt nanocrystals, but also represents a pivotal step forward toward the rational synthesis of metal nanocrystals.     

Synthesis of Some Surfactants Based on Polytriethanolamine and Investigation of Their Surface Active Properties

New modified surfactants were developed by esterification of ethoxylated polytriethanolamine with oleic acid. Triethanolamine was polymerized at three different times 1.30, 2.30, and 3.30 hours to give (P₄, P₆, and P₈) where 4, 6, and 8 refer to the degree of polymerization. The prepared polymer (P₈) was ethoxylated at three different molar ratios of ethylene oxide (40, 100, and 120) and named E(en)P₈. Then the ethoxylated polymers were esterified with oleic acid and abbreviated as E(en)P₈O_m. The surface properties for these surfactants were determined by measuring the surface tension. The structure was confirmed using the elemental analysis, (FTIR, ¹H, ¹³C NMR) spectroscopic.     

氯硝柳胺透皮控释给药的研究

用Ｖａｌｉａ－Ｃｈｉｅｎ双室扩散池进行了氯硝柳胺体外透皮的研究，发现氯硝柳胺乙醇混悬液有较高的渗透速率且服从零级动力学模型，透皮促进剂油酸比氮酮具有更好的促渗作用，氮酮与丙二醇或油酸合用均有协同作用．研究结果表明，氯硝柳胺能制成长效贴剂，且在２３～７２ｈ之间缓慢平稳释药．用ＩＲ、ＤＳＣ研究了氮酮和油酸的作用机理．     

Strategies for synthesis of epoxy resins from oleic acid derived from food wastes

The use of biomass‐sourced chemical feedstocks creates a conflict over land use between food and fuel/chemical production. Such conflict could be reduced by making use of the annual 1.3 Pg food waste resource. Oleic acid is available from seed oils such as pumpkin, grape, avocado and mango. Its esterification with diols 1,3‐propanediol, resorcinol and orcinol was used to form diesters and the naturally occurring norspermidine was used to prepare a diamide, all under ambient conditions. These compounds were then epoxidized and polymerized. When esterification was followed by epoxidation and subsequent curing at elevated temperature with p‐phenylenediamine or diethylenetriamine, hard insoluble resins were formed. When the sequence was changed such that the epoxidized oleic acid was first reacted with cis‐1,2‐cyclohexanedicarboxylic anhydride and then esterified with orcinol and resorcinol, insoluble crosslinked polymers were also obtained. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 3159–3170