桐油高压水解制备α-桐酸的工艺研究

为探索利用桐油高压水解制备α-桐酸的工艺条件,在单因素实验基础上,以桐油水解率和α-桐酸保留率为响应值,采用响应面实验对高压水解桐油的水解条件(水解温度、水解时间和水油体积比)进行了优化。结果表明:桐油高压水解制备α-桐酸的最佳工艺参数为水解温度230℃、水解时间4 h、水油体积比3∶1,该工艺条件下桐油的水解率为90.26%,α-桐酸保留率为93.01%。     

羟基硅油共聚改性阳离子水性聚氨酯的合成和性能

首先将二乙烯三胺与环氧氯丙烷反应合成中间体,并采用2,4-甲苯二异氰酸酯、聚醚二元醇、羟基硅油等合成羟基硅油共聚改性水性聚氨酯预聚体,然后将中间体与预聚体反应,合成了羟基硅油共聚改性阳离子水性聚氨酯乳液.结果表明,羟基硅油共聚改性阳离子水性聚氨酯中含氯丙醇基—CH2—CH(OH)—CH2Cl;当二乙烯三胺和环氧氯丙烷的摩尔比为1∶3,n(—NCO)∶n(—OH)=2.7,n(—NH —OH)∶n(—NCO)=1.3时合成的羟基硅油共聚改性阳离子水性聚氨酯乳液可以成膜、稳定性好,乳液的粒径呈正态分布.     

脂肪酸微生物转化生产羟基脂肪酸的研究进展

羟基脂肪酸是一种在生物可降解聚合物材料、化工、食品及机械等行业具有十分重要用途的化合物：对天然底物脂肪酸通过微生物转化方法生产羟基脂肪酸所涉及的微生物种类、微生物转化的作用机理和发酵条件等,特别是转化脂肪酸生产ω-1、ω-2和ω-3-羟基脂肪酸的细胞色素P450系统进行了较系统的分析和阐述,并对羟基脂肪酸的生产及发展趋势作了展望,为进一步研究和工业化生产羟基脂肪酸提供了基础。     

纳米固色剂Tinokin VG帮您解决牢度难题

常州市广华助剂有限公司生产的纳米固色剂Tinokin VG是应用独特工艺合成的多种环氧基、氨基及聚醚改性的有机硅共聚高分子化合物。其粒径在几十纳米之间，外观为淡黄色透明液体。易溶于水；属阳离子性，pH值4．0-5．0。     

纳米固色剂Tinokin VG帮您解决牢度难题

常州市广华助剂有限公司生产的纳米固色剂Tinokin VG是应用独特工艺合成的多种环氧基、氨基及聚醚改性的有机硅共聚高分子化合物。其粒径在几十纳米之间，外观为淡黄色透明液体，易溶于水；属阳离子性，pH值4．0-5．0。     

MTBSTFA衍生化结合GC-MS分析镇江香醋不挥发羧酸

以镇江香醋为研究对象,利用N-特丁基二甲基硅烷基-N-甲基三氟乙酰胺(N-(tert-butyldimethylsilyl)-N-methyltrifluoroacetamide,MTBSTFA)衍生化结合气相色谱-质谱法(GC-MS)分离鉴定香醋中不挥发羧酸,共鉴定并定量61种不挥发化合物,包括17种氨基酸、13种芳香酸、11种羟基酸、8种长链脂肪酸、7种二元及多元酸(不含羟基)、1种含硫有机酸、1种酮酸,2种杂环酸和1种不挥发酸酯。新检测到2-糠酸、乙醇酸、3-羟基丙酸、甘油酸、扁桃酸、对羟基苯乙酸、2,6-二羟基苯甲酸、原儿茶酸、阿魏酸、柠檬酸、芥子酸、没食子酸、咖啡酸等24种不挥发有机酸。研究结果表明,香醋中羟基酸(16.01 g/L)含量最高,其次是杂环酸(597. 3 mg/L)和氨基酸(546. 5 mg/L);单个酸含量大于100 mg/L的有乳酸、焦谷氨酸、琥珀酸、精氨酸、草酰乙酸和2-羟基-3-苯丙酸(从高到低依次)。该研究将为我国食醋品质的提升奠定基础。     

低黏度阳离子淀粉的制备及其表面施胶性能研究

以玉米原淀粉为原料,经盐酸适度酸解后,通过3-氯-2-羟丙基三甲基氯化铵醚化制备低黏度阳离子淀粉。研究了盐酸的用量、反应温度和反应时间对酸解淀粉黏度的影响,探讨了阳离子醚化剂的用量对阳离子淀粉黏度的影响。在水介质中,盐酸用量5%,反应温度35℃,反应时间3h,阳离子醚化剂用量2.5%,制备的低黏度阳离子淀粉即可达到表面施胶的要求。表面施胶实验结果表明,低黏度阳离子淀粉比氧化淀粉和阳离子淀粉具有更好的表面施胶性能。     

正交试验探讨橡胶籽油亚临界水解反应

以橡胶籽油为原料,在间歇式高温高压反应釜中进行亚临界水解反应,分别考察了反应温度、反应时间、水油体积比对水解率的影响.应用正交试验得出水解反应的较适宜条件为:反应温度290 ℃,反应时间40 min,水油体积比为4:1.在此条件下水解率可达96.8%.通过超高效液相色谱(UPLC)检测分析,橡胶籽油水解产物主要由亚油酸、油酸、亚麻酸、棕榈酸、硬脂酸5种脂肪酸组成.     

石榴籽油的提取及成分分析

探讨了石榴籽油提取过程中受溶剂、温度、回流时间的影响因素,确定了石榴籽经石油醚,在85℃下回流2h提取、皂化和甲基化得到的总脂肪酸甲酯经GC 分析,共检出12种成分.确定脂肪酸成分为棕榈酸(2.5%)、硬脂酸(1.6%)、亚油酸(4.8%)、油酸(4.7%)、花生酸(0.4%)、花生一烯酸(0.8%)、花生二烯酸 (0.3%)、山嵛酸 (0.2%)、石榴酸(62.9%)、α-桐酸(15.6%)、β-桐酸(6.0%)、未知酸(0.2%).     

胭脂虫酸染丝织物时钛离子前媒工艺的探讨

将钛离子前媒处理后的丝织物,采用天然染料胭脂虫酸进行染色,以丝织物的K／S、H值进行表征,对媒染剂浓度、温度、时间三个工艺因素进行了单因素实验,得到了钛离子前媒处理的最佳工艺参数（媒染液浓度510-3mol／L,40℃,40min）。用钛离子分别与丝的模拟物-丝肽、胭脂虫酸刺成配合物,测定配合物的红外光谱,丝肽中-NH2,酰胺Ⅰ、酰胺Ⅱ、羟基、羧基;胭脂虫酸分子中葡萄糖剩基上环状C-O-C,醌结构中的酚羟基、羧基等基团参与了与钛离子的配合反应。     

量子化学计算法比较不同脂肪酸分子的反应活性位点

为了探究不同链长及不饱和度脂肪酸反应活性位点的异同,采用量子化学计算的方法,运用Gaussian 09软件,在m06-2x/def2tvzp理论水平上对6 种碳链长度和不饱和度有差异的脂肪酸分子进行结构优化,再在ma-def2tzvp基组下对其进行单点能计算。然后对分子表面静电势、平均局部离子化能、前线分子轨道以及简缩福井函数进行分析,并得到可视化结果。结果表明：饱和脂肪酸的亲核反应活性位点在羟基氢上,其中辛酸的亲电反应活性位点在氧原子附近,随着碳链长度的增加,棕榈酸和硬脂酸的羧基基团几乎不发生亲电反应。不饱和脂肪酸中,油酸的氧原子附近亲核活性较高,碳碳双键处亲电活性较高,随着双键数量的增多,亚油酸和亚麻酸的反应活性位点均在碳碳双键,并且对于链长相同的不饱和脂肪酸而言,随着不饱和度的增加,脂肪酸的反应活性逐渐增强。本研究结果可为揭示脂肪酸的不同结构与性质之间的关系提供理论依据,同时也对食品的油脂工业中关于脂肪酸的选择具有参考意义。     

仿生织物用防水剂甲基羟基硅油的合成研究

合成一种防水剂甲基羟基硅油,涂于织物表面,可以用于织物防水,起到如荷叶、紫罗兰叶等植物叶子表面不沾水的仿生自洁功能。以二甲基环硅氧烷DMC和乙酸为原料,以浓硫酸为催化剂,合成了甲基羟基硅油。以硫酸为链引发剂,以乙酸为链终止剂,探讨了链引发、链增长和链终止的阳离子开环聚合反应机理。考察了反应时间、反应温度和催化剂用量等因素对产品质量的影响。实验结果表明,该工艺的最佳反应条件为:反应温度140℃,反应时间4h,硫酸用量(催化剂)2%,其中反应温度对反应过程影响显著。     

从天然紫胶中提取紫胶桐酸的工艺条件

以颗粒紫胶为原料提取紫胶桐酸,在不加入任何有机溶剂的情况下,可获得质量分数>98%的紫胶桐酸产品。研究了皂化时间、皂化化温度、盐析时间、以及亚硫酸钠对紫胶桐酸收率的影响,结果表明:NaOH质量分数25%、料液比(g∶mL)1∶6,皂化时间96h、无水Na2SO3的加入量为紫胶质量的10%,盐析时间18h,紫胶桐酸质量分数可达98.85%~99.43%、收率可达24.64%~25.16%。利用有机元素分析仪、红外光谱方法、显微溶点测定仪对提取的紫胶桐酸结构进行了表征。     

羊毛脂的理化指标及主要成分分析

羊毛脂的理化指标和组成对其使用性能影响较大,因而采用国标等方法对原料羊毛脂的熔点、水分及挥发物含量、灰分含量、酸值、过氧化值、碘值、色度等基本理化指标进行分析,并通过薄层色谱及柱层析对其主要成分进行分析鉴定,采用气质联用色谱对羊毛醇和羊毛酸进行定性定量分析。结果表明：与精制羊毛脂（药典级）相比,原料羊毛脂色泽较深,水分及挥发物含量、灰分含量、碘值与酸值略高;羊毛脂的主要组成成分为脂肪酸酯、羟基酸酯、游离甾醇及多羟基物残留物,分别占羊毛脂总质量的55.14%、25.57%、4.04%和13.15%;原料羊毛脂中甘油三酯未检出;羊毛醇的主要组成为胆甾醇与羊毛甾醇,相对含量分别为44.31%与14.62%,羊毛脂中胆甾醇和羊毛甾醇含量分别为10.41%、3.43%（以全样原料羊毛脂计）;羊毛酸的主要组成为饱和脂肪酸,碳链长度为C13~C27,其中支链脂肪酸相对含量高达62.03%,异构支链脂肪酸相对含量为27.56%,反异构支链脂肪酸相对含量为34.47%。     

Chemical Modification of Pigskin Gelatin: Factors Affecting the Esterification of Gelatin with Fatty Acid

ABSTRACT: This study investigated the esterification of pigskin gelatin with fatty acid catalyzed by acid in aqueous medium. Factors affecting the esterification reaction B temperature, pH, water content, fatty acid concentration, fatty acid type and reaction time- were elucidated in the view of optimizing the reaction. Under the same experimental conditions, increase in fatty acid concentration permitted the determination of the maximum amount of fatty acid that could be esterified per unit weight of gelatin and demonstrated that not all the hydroxyl functional groups present in the gelatin could be blocked by the fatty acid chains.     

Impact of fatty acid composition on the accuracy of mid-infrared fat analysis of farm milks

Our objective was to determine whether data from a previous study using model milk emulsions to characterize the influence of variation in fatty acid chain length and unsaturation on mid-infrared (MIR) fat predictions could be used to identify a strategy to improve the accuracy of MIR fat predictions on a population of farm milks with a wide variation in fatty acid chain length and unsaturation. The mean fatty acid chain length for 45 farm milks was 14.417 carbons, and the mean unsaturation was 0.337 double bonds per fatty acid. The range of fatty acid chain lengths across the 45 farm milks was 1.23 carbons, and the range in unsaturation was 0.167 double bonds per fatty acid. Fat B (absorbance by the carbon-hydrogen stretch) MIR predictions increased and fat A MIR (absorbance by the ester carbonyl stretch) predictions decreased relative to reference chemistry with increasing fatty acid chain length. When the fat B MIR fat predictions were corrected for sample-to-sample variation in unsaturation, the positive correlation between fat B and fatty acid chain length increased from a coefficient of determination of 0.42 to 0.89. A 45:55 ratio of fat B corrected for unsaturation and fat A gave a smaller standard deviation of the difference between MIR prediction and reference chemistry than any ratio of the fat B (without correction for unsaturation) and fat A or either fat B or fat A alone. This demonstrates the technical feasibility of this approach to improve MIR testing accuracy for fat, if a simple procedure could be developed to determine the unsaturation of fat in milk rapidly and to correct the fat B reading for the effect of unsaturation before being combined with fat A.     

微波皂化法制备紫胶桐酸

采用常压微波法对天然紫胶树脂皂化,后经盐析、结晶等一系列操作,制备紫胶桐酸。单因素试验考察微波功率、碱液质量分数及微波时间3个主要因素对紫胶桐酸得率的影响,并以紫胶桐酸得率为响应值,采用响应曲面法对皂化工艺进行优化试验。结果表明,在微波功率200W、碱液质量分数25.8%、微波时间31min条件下,紫胶桐酸得率最大,达到21.90%。由红外光谱、X射线衍射、差示扫描量热、扫描电镜等表征可知,微波皂化法制备的紫胶桐酸结晶均匀、杂质较少。微波皂化法制备紫胶桐酸简单易行,能有效缩短制备时间,且得率较高。     

Amphiphilic association structures in a model skin lotion with hydroxy acids

The phase diagrams were determined of lactic and isohexanoic hydroxy acids as well as salicylic acid with water, a non-ionic surfactant and a paraffinic oil to outline the influence of the hydroxy acids on the structure in a model for a skin lotion. The results showed the influence of the acid to be similar to that of the oil, but that the difference in chain length between the two alpha acids had only insignificant influence. The results are discussed from two aspects: the structures involved in the lotion as applied and the action of the lotion residue on the skin after the evaporation of the water.     

乳酸菌发酵过程发酵液脂肪酸组生态位的异质性

为探究乳酸菌发酵过程中发酵液脂肪酸组生态位的异质性,测定8 种乳酸菌发酵过程中乳酸菌活菌数和发酵液脂肪酸组,分析生态位宽度和重叠度与乳酸菌生长的关系。结果表明,不同乳酸菌生长能力差异显著,鼠李糖乳杆菌FJAT-13807生长能力最强,嗜热链球菌FJAT-43774最弱。8 种乳酸菌发酵液脂肪酸组共检测到91 条生物标记,其中直链脂肪酸12 条、支链脂肪酸70 条、未能分离的脂肪酸9 条,其含量顺序为直链脂肪酸＞支链脂肪酸＞未能分离的脂肪酸。不同乳酸菌发酵液脂肪酸总量差异显著（P＜0.05）,但乳酸菌发酵液脂肪酸总量与菌生长能力无直接相关性。发酵初期（1 h）,不同乳酸菌发酵液的脂肪酸生态位宽度差异不显著,菌株间脂肪酸生态位重叠程度较高,活菌数较低,环境容量较大,生态位宽度与重叠无相关性;发酵中期（24 h）,乳酸菌发酵液脂肪酸生态位宽度和重叠发生较大分化,影响处于对数生长期的乳酸菌生长模式,生态位宽度增加,乳酸菌生长速度下降,活菌数呈线性方程增长;生态位宽度减少,乳酸菌生长速度增加,活菌数呈抛物线方程增长;生态位宽度维持,乳酸菌生长速度维持原有方式;发酵后期（48 h）,乳酸菌发酵液脂肪酸生态位宽度与重叠也有类似分化,此时,乳酸菌处于稳定消亡期,生态位宽度较宽,乳酸菌生长能力下降,活菌数呈指数方程下降;生态位宽度较窄,乳酸菌生长能力增强,活菌数呈一元三次方程变动;生态位宽度维持,乳酸菌维持原有的规律,活菌数呈幂指数下降。乳酸菌发酵液脂肪酸生态位宽度和重叠的变化可用于乳酸菌生长势和资源利用率评估,为乳酸菌生长生态学研究提供新思路。     

Surface active molecules: preparation and properties of long chain nα-acyl-l-α-amino-ω-guanidine alkyl acid derivatives

A new route for the synthesis of long chain N ^α-acyl- l -α-amino-ω-guamdine alkyl acid derivatives, with cationic or amphoteric character has been established. The general formula of these compounds is shown below.
A physico-chemical and antimicrobial study of these products as a function of the alkyl ester or sodium salt (R), the straight chain length of the fatty acid residue ( x ) and the number of carbons between the ω-guanidine and ω -carboxyl group ( n ) has been investigated.
The water solubility, surface tension, critical micelle concentration (c.m.c.) and minimum inhibitory concentration (MIC) against Gram-positive and Gram-negative bacteria (including Pseudomonas) has been determined.
Dicyclohexylcarbodiimide has been used to condense fatty acids and α -amino-ω-guanidine alkyl acids. In these conditions protection of the ω-guanidine group is not necessary. The main characteristic of this synthetic procedure is the use of very mild experimental conditions (temperature, pH) to form the amide linkage which leads to pure optical compounds in high yield in the absence of electrolytes.
The results show that some structural modifications, particularly the protection of the carboxyl group, promote variations of the surfactant and antimicrobial properties. Only those molecules with the blocked carboxyl group (cationic molecules, where R = Me, Et or Pr) showed a good surfactant and antimicrobial activity. When the carboxyl group was unprotected (amphoteric molecules, where R = Na⁺) the resulting compounds were inactive.