氧化铝柱层析分离纯化磷脂的工艺过程

研究了氧化铝柱层析同时分离纯化卵磷脂和脑磷脂的工艺过程,包括上样、洗脱工艺条件优化以及氧化铝再生等.结果表明较佳上样条件为：上样质量浓度为100 g/L,流动相为纯甲醇,流速为1.0~2.5 BV/h;较佳洗脱条件为：甲醇 氯仿溶液中氯仿的体积分数为80%;较佳再生条件为：用5个床层体积的甲醇冲洗层析柱.通过连续上样实验,验证了该工艺过程的可行性,可以同时得到质量分数大于95%的卵磷脂产品和质量分数大于80%的脑磷脂产品.氧化铝柱层析可以用于同时分离纯化卵磷脂和脑磷脂,具有粗磷脂处理量大以及产率和纯度高等优点     

高纯度新疆胡麻卵磷脂的制备

以粉末状新疆胡麻磷脂粗品为原料,经金属离子沉淀法、柱层析法、全溶剂萃取法及薄层层析富集法等工艺制备了高纯度卵磷脂,并研究了金属离子沉淀法对柱层析分离磷脂混合物效果的影响。结果表明:以金属离子锌为复合沉淀离子,以中性氧化铝为吸附剂,以氯仿:甲醇:水=65:25:4(V:V:V)为洗脱剂进行等度洗脱,可获得高纯度的卵磷脂精品;未经金属离子沉淀法处理的磷脂混合物,氧化铝吸附柱层析法无法分离得到单一组分的卵磷脂,对于该部分磷脂混合物,研究采用薄层层析富集法获得卵磷脂纯品。所得卵磷脂采用红外光谱、紫外光谱、一维多次展开薄层层析、二维双液展开薄层层析等手段进行了鉴定。     

栉孔扇贝营养物的提取与分析

目的:水提法提取栉孔扇贝中营养物质并测定其多糖、牛磺酸和胆碱的含量。分析营养物提取率与牛磺酸、胆碱、多糖含量的关系。方法:超声波破碎组织法;水提法提取栉孔扇贝中营养物质;苯酚-硫酸显色法测定多糖;乙酰丙酮-甲醛显色法测定牛磺酸;雷氏盐沉淀比色法测定栉孔扇贝中胆碱的含量。结果:当1g组织加30ml水并用超声破碎时,水提物出率最高达23%;多糖在栉孔扇贝水提物中的含量达3.60%～15.09%;牛磺酸的含量为1.13%～1.25%;胆碱的含量为0.31%～0.38%。结论:栉孔扇贝中营养物的提取率受各种提取条件影响较大;营养物中的牛磺酸、胆碱含量受各种提取条件影响不大,而多糖的含量则较大。并且,牛磺酸、胆碱、多糖的含量与营养物提取率不呈正相关。     

含水量对氧化铝柱色谱法同时分离纯化卵磷脂和脑磷脂的影响

系统地研究了固定相初始含水量和流动相含水量对氧化铝柱色谱法同时分离纯化卵磷脂和脑磷脂的影响.结果表明：在实验范围内,氧化铝的初始含水量对氧化铝柱色谱法同时分离纯化卵磷脂和脑磷脂有很大的影响,而流动相含水量则影响不大.氧化铝初始含水量在8%(质量分数)和流动相含水量在0.1%～1.1%(体积分数)范围内,卵磷脂和脑磷脂可实现基线分离,PC的回收率可达90%以上,PE的回收率可达40%以上.并对实验结果的重现性进行了考察.研究结果除了对卵磷脂和脑磷脂的精制有一定的指导作用外,对其他天然产物分离纯化的研究和生产也有一定的借鉴意义.     

可裂解的表面活性剂(英)(待续)

可裂解的表面活性剂值得关注有几方面的原因。首先,弱键联接的表面活性剂分子结构迎合了改善两亲性物质生物降解能力的发展趋势。裂解可以被酶催化,其生物降解作用可能与污水处理的一般发机理相符合。另外,这些表面活性剂也可以妥,例如,用酸、碱、此一（ＵＶ）、热或臭氧诱发降解反应,对酸、碱不稳定的表面活性剂已引起特别关注,因为在初始步骤所需的稳定性与其在后续步骤中应易裂解并不冲突。综述了制可裂解性表面活性剂的主     

Supplemental choline for prevention and alleviation of fatty liver in dairy cattle

Two experiments were conducted to evaluate if supplementing rumen-protected choline (RPC; Reashure, Balchem Encapsulates, Slate Hill, NY) could prevent or alleviate fatty liver in dairy cattle. The first experiment evaluated the effect of supplementing RPC on hepatic triacylglycerol (TAG) accumulation during fatty liver induction. Twenty-four dry cows between 45 to 60 d prepartum were paired by body weight (BW) and body condition score (BCS) and randomly assigned to control or supplementation with 15 g of choline as RPC/d. From d 0 to 6, before treatment application, all cows were fed 1.4 kg/d of concentrate and forage ad libitum. Samples of blood and liver, obtained during the pretreatment period, were used for covariate adjustment of blood metabolites and liver composition data. During fatty liver induction (d 7 to 17), cows were fed 1.4 kg/d of concentrate with or without supplementation with RPC, and forage intake was restricted, so cows consumed 30% of the total energy requirements for pregnancy and maintenance. Supplementation with RPC during fatty liver induction did not affect plasma glucose and plasma β-hydroxybutyrate (BHBA) concentration but did decrease plasma nonesterified fatty acid (NEFA; 703 vs. 562 μEq/L, SE = 40) and liver TAG accumulation (16.7 vs. 9.3 μg/μg of DNA, SE = 2.0). In the second experiment, we evaluated the effect of supplementing RPC on the clearance of liver TAG when cows were fed ad libitum after the induction of fatty liver by feed restriction. Twenty-eight cows between 45 and 60 d prepartum were paired according to BCS and BW and assigned to treatments. Fatty liver was induced by feeding 1.4 kg/ d of concentrate (without RPC) and restricting forage intake, so cows consumed 30% of maintenance and pregnancy energy requirements for 10 d. From d 11 to 16, after feed restriction, cows were fed forage ad libitum and 1.4 kg/d of concentrate with or without RPC. Treatments were not applied during fatty liver induction; however, following feed restriction, liver for cows assigned to control and RPC treatments contained 6.8 and 12.7 μg of TAG/μg of DNA, respectively. Measurements obtained before treatment served as covariates for statistical analysis. During the depletion phase, plasma glucose, BHBA, and NEFA were not affected by treatment. Liver TAG, expressed as covariate adjusted means, was 6.0 and 4.9 μg/μg of DNA (SE = 0.4) on d 13, and 5.0 and 1.5 μg/μg of DNA (SE = 0.9) on d 16 for control and RPC, respectively. Rumen-protected choline can prevent and possibly alleviate fatty liver induced by feed restriction.     

正相色谱法测定大豆磷脂中的磷脂酰胆碱

目的建立正相色谱法测定大豆磷脂中磷脂酰胆碱含量,用于大豆磷脂类保健食品生产过程中该物质含量的测定和质量控制。方法采用硅胶柱(4.6 mm×250 mm,5.0μm)进行分离;色谱条件为流动相:异丙醇:正己烷:蒸馏水=70:16:14(V:V:V),等度洗脱,流速:1.0 m L/min;柱温:40℃;进样量:10μL;检测波长:205nm;并进行方法学验证,考察方法检测限、精密度、回收率等指标。结果磷脂酰胆碱峰面积与其浓度呈良好的线性关系,线性范围为0.1~0.8 mg/m L(r=0.9999),检出浓度0.04μg/m L,检出限为20μg/g,定量限为66.666μg/g,精密度(RSD)为0.6%,平均回收率99.37%(n=9)。结论本文建立的方法灵敏度高,重复性好,且具有很好的专属性,能够应用于大豆磷脂类保健食品中磷脂酰胆碱含量的检测。     

胆碱模块自动化合成11C-carfentanil及Micro PET显像

为快速、高效合成中枢神经阿片受体显像剂¹¹C-carfentanil(¹¹C-CFN),对国产商业化¹¹C-胆碱合成模块略做改动,并优化了合成条件。结果表明,采用4-哌啶乙酸钠,4-[(1-丙羰基)苯胺]-1-(2-苯乙基)[钠盐]作前体,DMSO作溶剂,¹¹CH_3-triflate作甲基化试剂,在胆碱模块上采用反应瓶法,可自动化合成¹¹C-CFN。合成的¹¹C-CFN活度＞14.8 GBq、比活度＞1.4×10¹⁴Bq/g、放化纯度＞99%,校正合成效率＞80%（n=55,以¹¹CH₃-triflate计算）,全部合成时间为18 min。经Micro PET/CT证实,¹¹C-CFN可用于μ阿片受体的PET显像研究。     

食品中磷脂酰胆碱检测技术的研究进展

食品中磷脂酰胆碱含量的测定方法主要有紫外可见分光光度法(UV-VIS)、薄层色谱法(TLC)、高效液相色谱法(HPLC)等。本文分别概述了这些传统方法,同时介绍了核磁共振波谱法(NMR)和荧光分光光度法(FS)两种最新检测技术,并对不同方法的优缺点进行了初步的探讨,为从事功能食品功效成分及食品安全检测人员提供信息和参考。     

Aerobic Alcohol Oxidation by Ruthenium Species Stabilized on Nanocrystalline Magnesium Oxide by Basic Ionic Liquids

The selective oxidation of various alcohols into their corresponding aldehydes and ketones was achieved by ruthenium species stabilized on the nanocrystalline magnesium oxide (NAP‐MgO) by the incorporation of choline hydroxide, a basic ionic liquid, in excellent yields. The procedure is simple, efficient and environmentally benign. The catalyst can be used for four cycles with almost consistent activity.