Phosphorylated Allylchlorides: A Source of new Structures and Transformations

Abstract

General methods have been elaborated for the synthesis of O (or S)-phosphorylated vinylcholines, including the corresponding betaines of mono-, bis- and polymer structures, 5-membered heterocycles with P, O, S, N atoms in the cycle and exo- CHX= (X=H, C1) bond. The key substances, O-phos- phorylated allylchlorides, were obtained either by the well known Perkov reaction or according to scheme (I), worked out by us. The scheme is based on the reactions of 3- or 4-coordinated phosphorus with substituted ketones in the presence of triethylamine (B:).     

超高效液相色谱-串联质谱快速测定食品中的新品种甜味剂爱德万甜

建立了超高效液相色谱-串联三重四极杆质谱快速筛查和确证食品中的新品种甜味剂爱德万甜的方法。样品经甲醇-水（50：50,v/v）超声提取,离心,取上清液过滤膜。采用Agilent SB-C18（150 mm×2.1 mm,5 μm）色谱柱分离,梯度洗脱,在电喷雾离子源的正离子电离模式下,用多反应监测（MRM）方式采集数据,根据保留时间和定性离子对进行定性筛查,根据峰面积和定量离子进行定量分析。结果表明：方法检出限（LOD）为0.03 mg/kg（信噪比S/N ≥ 3）,定量限（LOQ）为0.10 mg/kg（S/N ≥ 10）,回收率为80.3%~98.0%,在0.01~1.0 mg/L范围内均有良好的线性,相关系数r²均大于0.997。该方法快速、简便易行、灵敏、准确,适用于饮料、酸奶和果冻中的新品种甜味剂爱德万甜的批量检测。     

Modification of milk using immobilized enzymes

The preparation and use of immobilized enzyme systems for the modification of the principle components of milk—casein, lactose, and butterfat—are discussed. Design of a pilot-scale bioreactor is described. Also the use of tea polyphenols as a crosslinking agent is reported. A review of methods for hydrolyzing lactose and characteristics of a concentrated liquid sweetener derived from dairy byproducts is presented. Further, the application of immobilized esterases to modify milk, cream, and butterfat is reported.     

HPLC法同时测定乳酸菌饮料中2种防腐剂和3种甜味剂

建立了一种高效液相色谱法同时测定乳酸菌饮料中2种防腐剂（苯甲酸、山梨酸）、3种甜味剂（乙酰磺氨酸钾、天门冬酰苯丙氨酸甲酯、糖精钠）的方法。样品经12％乙酸锌溶液和12％亚铁氰化钾溶液处理后,用C18色谱柱分离-以甲醇和0．02mol／L乙酸铵溶液为流动相梯度淋洗,紫外检测波长为230,205nm,可在30min内将5种组分完全分离,测定结果的相对标准偏差为1．1％-4．3％（n=5）,加标回收率为90％-102％。     

Sweet-Tasting Ionic Conjugates of Local Anesthetics and Vasoconstrictors

Local anesthetics are widely utilized in dentistry, cosmetology, and medicine. Local anesthesia is essential to providing a pain-free experience during dental and local surgeries as well as cosmetic procedures. However, the injection itself may produce discomfort and be a source of aversion. A novel approach toward the taste modulation of local anesthetics is proposed, in which the anesthetics of the “-caine” family serve as cations and are coupled with anionic sweeteners such as saccharinate and acesulfamate. Ionic conjugates of vasoconstrictor epinephrine such as epinephrine saccharinate and epinephrine acesulfamate have also been synthesized. Novel ionic conjugates were developed using anion exchange techniques. Reported compounds are sweet-tasting and are safe to use both topically and as injections.     

磺胺类人工合成甜味剂的毛细管电泳/电导法分离检测

采用15 mmol/L Tris-10 mmol/L H3BO3-0.2 mmol/L EDTA为电泳运行液,0.2%四乙烯五胺为电渗流抑制剂,融硅石英毛细管(45 cm×50 μm),负高压分离(-15 kV),柱端接触式电导检测,建立了磺胺类人工合成甜味剂(糖精钠、安赛蜜、甜蜜素)的高效毛细管电泳/电导法分离检测方法.糖精钠、安赛蜜、甜蜜素的线性检测范围分别为0.8 ～120、1.1 ～120、1.5 ～120 μmol/L,检出限分别为0.3、0.4、0.6 μmol/L.详细讨论了电泳运行液的组成、浓度以及进样方式对灵敏度和分离度的影响.该法用于市售饮料中3种甜味剂的分离检测,结果满意.     

合成甜味剂检测技术的研究进展

综述近十年来食品中合成甜味剂的检测技术。着重介绍光谱法、毛细管电泳法、流动注射分析法、高效液相色谱法以及液相色谱串联质谱法等。结合实际需求,比较不同方法的特点,并对合成甜味剂检测技术的发展进行了展望。     

超高效液相色谱-高分辨质谱法测定蜂蜜中的苯甲酸、山梨酸、安赛蜜与糖精钠

建立了蜂蜜中苯甲酸、山梨酸、安赛蜜、糖精钠的超高效液相色谱-高分辨质谱分离测定方法。样品采用甲醇-水溶液(10∶90)提取,Diamonsil Plus C18色谱柱进行色谱分离,以0.5 mmol/L乙酸铵溶液和甲醇为流动相梯度洗脱,通过高分辨负离子扫描模式进行定性,外标法定量。结果表明,4种物质在0.02~2.0mg/L范围内均具有良好的线性关系,相关系数为0.998 7~0.999 7。苯甲酸、山梨酸的方法定量下限为0.5mg/kg,安赛蜜、糖精钠为0.3 mg/kg。在低、中、高3个加标浓度下,方法的回收率为89.0%~104.0%,相对标准偏差(RSD)为2.0%~7.9%。该方法灵敏、简单、快速,定性准确可靠,适用于大批量蜂蜜中苯甲酸、山梨酸、安赛蜜、糖精钠的检测。     

Analytical methodologies for determination of artificial sweeteners in foodstuffs

Artificial high-intensity sweeteners are used increasingly frequently for food production. The food industry tends to highlight beneficial aspects of their use (e.g., tooth friendliness, increasing the quality of life of those suffering from different forms of diabetes and the possibility of weight control without anyone sacrificing their favorite “unhealthy” drinks or snacks). However, some consumers are deeply concerned about the safety of artificial sweeteners and claim that the food industry is replacing natural beet sugar or cane sugar for purely economic reasons.Most of these food additives have a maximum usable dose or a maximum allowable concentration specified for a given type of food. In order to assure consumer safety, it is necessary to control the content of sweeteners in foodstuffs. Analytical methods (including high-performance liquid chromatography, ion chromatography, thin-layer chromatography, gas chromatography, capillary electrophoresis, flow-injection analysis, electroanalysis and spectroscopy) can determine sweeteners individually and simultaneously in mixtures. This review focuses on the application of some popular analytical procedures for determination of artificial sweeteners in food.     

Determination of cyclamate in foods by high performance liquid chromatography-electrospray ionization mass spectrometry

A high sensitive method for determination of cyclamate in foods by ion-pair high-performance liquid chromatography-electrospray ionization mass spectrometry was developed and validated. The separation was achieved on a C₈ column with 5 mM tris(hydroxymethyl)aminomethane aqueous solution (pH 4.5, adjusted by acetic acid) as mobile phase with an isocratic mode. The quantification of target compound was completed using a selected ion recording (SIR) at m/z 178 obtained from ESI-mode. Tiopronin was used as internal standard for the quantification of cyclamate. The correlation coefficient of the calibration curve were better than 0.996, in the range of 50-5000 ng/mL. The limit of detection is 5 ng/mL, the limit of quantification is 20 ng/mL. The inter- and intra-day accuracy, precision were investigated in detail. The method can be used to monitor effectively the content of the artificial sweetener in foods. The method has obvious merits such as high sensitivity, specificity and simply versus other methods reported.