甘蓝叶绿素锌钠盐的制备及性质研究

以甘蓝叶为原料,利用萃取得到叶绿素.经皂化、酸化、锌代等过程,制得叶绿素锌钠盐.结果表明,该产品水溶性好,对光、热稳定性较好,具有很好的耐受氧化剂和还原剂的能力.几种常见的食品添加剂对叶绿素锌钠盐的影响不一样.     

罗勒叶叶绿素锌钠盐的制备及其稳定性研究

通过正交试验研究罗勒叶中叶绿素浸提的最佳工艺条件,经过皂化、酸化、锌代及其成盐反应制备叶绿素锌钠盐,并对其稳定性进行研究.结果表明,罗勒叶叶绿素的最佳浸提工艺条件为:乙醇浓度100％,浸提时间50 min,料液比为1:10,温度控制在70℃.而其制备的叶绿素锌钠盐水溶性、耐热性、耐氧化还原性、在弱酸、中性及碱性条件下较稳定,但在光照条件下,稳定性差.常用的食品添加剂和一些金属离子对叶绿素锌钠盐的稳定性无影响,Cu2+、Fe3+对叶绿素锌钠盐的稳定性有较大的影响.     

蚕沙叶绿素锌钠盐的制备及其稳定性研究

利用蚕沙制备叶绿素锌钠盐溶液,采用分光光度计对叶绿素锌钠盐进行定性、定量测定,确定最大波长为412 nm。并对其稳定性进行研究。结果表明:叶绿素锌钠盐水溶性较好、耐热性、pH为2.66～13.01时的溶液稳定性较好,氧化剂(H_2O_2)、还原剂(Na_2SO_3)稳定性较好,Vc对叶绿素锌钠盐有一定保护作用,但对光不稳定。常见的食品添加剂(蔗糖、葡萄糖、食盐、柠檬酸)和一些金属离子(Ca~(2+)、Na~+、Mg~(2+))对叶绿素锌钠盐的稳定性无影响,而部分金属离子Cu~(2+)、Fe~(2+)、Al~(3+)对叶绿素锌钠盐的稳定性有较大的影响。     

叶绿素锌钠盐的理化性质及应用研究

对叶绿素锌钠盐的理化、光谱、与聚乙烯醇染色后薄膜的性能进行了研究。结果表明,叶绿素锌钠盐能溶于水,在412、639nm处有特征吸收峰,在中性溶液中稳定,热稳定性很好,有一定的抗氧化还原性,光稳定性较差。一般的食品添加剂,如食盐、葡萄糖、抗坏血酸对叶绿素锌钠盐的稳定性没有太大的影响。含叶绿素锌钠盐的塑料薄膜具有一定的保鲜性,但失重率较高,有待进一步提高。     

桑叶叶绿素锌钠盐的制备及其稳定性研究

利用桑叶制备叶绿素锌纳盐溶液,并对其稳定性进行研究。经过研究得到结论:叶绿素锌钠盐水溶性较好,耐热性、耐氧化还原性、pH为4.00～11.00时的稳定性较好,但光照条件下,稳定性较差。常见的食品添加剂(蔗糖、葡萄糖、食盐、柠檬酸)和一些金属离子(Al~(3+)、Ca~(2+)、Na~+、Mg~(2+))对叶绿素锌钠盐的稳定性无影响,而Cu~(2+)、Fe~(2+)对叶绿素锌钠盐的稳定性有较大的影响。     

由松针制取三种叶绿素钠盐及其稳定性的研究

为提高叶绿素的稳定性,以松针为原料,以乙醇水溶液为溶剂提取得到叶绿素,再经过皂化、酸化、铜代(或锌代、铁代)及加碱成盐等过程,分别制备得到叶绿素铜钠盐、叶绿素锌钠盐和叶绿素铁钠盐,将它们配成相同浓度的水溶液,颜色分别为深绿色、翠绿色和茶黄色。进而比较了它们对光、热、pH及氧化剂的稳定性,结果表明叶绿素铜钠对光照的稳定性最好;叶绿素锌钠对温度稳定性较好;pH会引起三者的异构化造成吸光值的改变;低氧化剂浓度下,三者均较为稳定,但高浓度时其稳定性均下降较快。     

红豆杉叶绿素提取及其锌钠盐对羊毛的染色

采用95%乙醇从红豆杉叶中提取叶绿素,优化提取工艺,并将其制备成叶绿素锌钠盐,对羊毛织物进行染色,研究了染色温度、色素用量对染色效果的影响。研究结果表明,从红豆杉叶中提取叶绿素的较佳工艺条件：采用95%乙醇,在提取温度60℃和料液比为1:15的条件下浸提2h。羊毛织物在制备的叶绿酸锌钠盐染液中染色,温度90℃时K/S值最大,且叶绿素锌钠盐用于羊毛织物染色具有较好的提升性。染色毛织物的水洗牢度较好,日晒牢度有待提高,在紫外光照射下,织物的最大吸收波长发生变化,K/S值有所降低。     

几种竹叶制备叶绿素锌钠的产量比较

以四种竹叶作为原料制备叶绿素锌钠盐，并对其产量进行比较。实验结果表明：用95％乙醇-石油醚（1：5，V：V）作浸提溶剂、65℃浸提6h、碱性条件皂化、ZnSO4浓度为10％、pH0．72锌代的条件下，毛竹叶制备叶绿素锌钠盐的产量最高，为0．2795g。     

叶绿素铬钠盐的制备及理化性质

由菠菜叶提取叶绿素并经皂化、酸化、铬代及成盐反应制备叶绿素铬钠,测定了它的紫外可见光谱,并与叶绿素铜(II)钠盐的紫外可见光谱进行比较,同时测定了叶绿素铬钠盐理化性质。实验结果表明:叶绿素铬钠盐在360.8、401.6、655.1nm处有特征吸收峰,紫外可见光谱与叶绿素锰(III)叶绿素镧(III)相似,证明铬离子已经配位到叶绿素卟啉环上,形成了叶绿素铬钠盐。叶绿素铬钠盐能溶于水,在中性溶液中稳定,有一定的抗氧化还原性,热稳定性好,光稳定性较差。其中食盐这种食品添加剂对叶绿素铬钠盐的稳定性影响不大。     

叶绿素锌钠盐的制备研究

此项研究以菠菜叶为原料，ＮａＯＨ、ＺｎＳＯ４劝辅料，乙醇、丙酮、石油醚为溶剂，经过物理、化学过程制得叶绿素锌钠盐。     

Speciation and removal of zinc from composted municipal solid wastes

This paper presents composting of the organic fraction of municipal solid waste containing 50,000 mg/kg of cellucotton and 7980 mg/kg of zinc carried out under laboratory conditions. In the initial material as well as the compost obtained, zinc, cadmium, copper, nickel, and lead were analyzed, and their forms were determined by means of sequential extraction. It was found that 65% of zinc occurs in the organically bound form. Removal of zinc from the waste through leaching and subsequent electrochemical separation from the leaching solution was also examined. A double extraction of the waste with sodium diphosphate(V) enables a reduction of zinc content to 1240 mg/kg. As a result of electrolysis of the leaching solution, 90.2% of Zn is separated on the cathode. This paper suggests a method for processing municipal solid waste with high zinc content based on extraction of the waste with sodium diphosphate(V) and composting. The leaching solution is recovered electrochemically.     

加工工艺对名优绿茶叶素变化的影响

用薄层扫描分析法测定了名优绿茶叶绿素组成的变化。结果表明，在针形茶加工过程中，chla、chlb呈下降趋势，pya、pyb呈上升趋势，cda、cdb变化较小。杀青工序和揉捻后做形前期是叶绿素破坏和脱镁叶绿素形成的主要阶段。主要类型名优绿茶叶绿素测定结果表明，chla、pya差异较大，其次是chlb，而cdb、cda、pyb的差异较小。揉捻对名优茶色泽品质有影响．揉捻型名茶叶绿素的含量低于未揉捻型名茶，而脱镁叶绿素的含量则相反。春茶后期以及夏秋季鲜叶加工过程叶绿素的过多破坏和脱镁叶绿素的大量形成是造成叶色发暗的主要原因。     

Assessment of production efficiency,physicochemical properties and storage stability of spray‐dried chlorophyllide,a natural food colourant,using gum Arabic,maltodextrin and soy protein isolate‐based carrier systems

The aim of this research was to study spray drying as potential action to protect chlorophyllide from environmental conditions for shelf‐life extension and characterisation of the powders. Six formulations were prepared with 7.5 and 10 g of carrier agents [gum Arabic (GA), maltodextrin (MA) and soybean protein isolate (SPI)]/100 mL of chlorophyllide solutions. The powders were evaluated for morphological characteristics (SEM), particle size, water activity, moisture, density, hygroscopicity, cold water solubility, sorption isotherms, colour and stability, during 90 days. All the powders were highly soluble, with solubility values around 97%. A significant lower hygroscopicity was observed for GA powders, whilst the lower X_m values obtained by GAB equation fitting of the sorption isotherms was observed for the 7.5 g MA/100 mL samples. All formulations, but the 1 (7.5 g SPI/100 mL of chlorophyllide), provided excellent stability to the chlorophyllide during 90 days of storage even at room temperature.     

不同浓度海水灌溉对库拉索芦荟中微量元素的影响

采用原子吸收分光光度法分析了不同浓度海水灌溉的3年生库拉索芦荟中Ca、Mg、Na、K、Mn、Zn、Fe、Cu、Ni、Pb、Cd、Cr共12种微量元素的含量。试验发现:各元素在芦荟中的含量差异较大,其中,Ca、Mg、Na、K含量丰富,Mn、Zn、Fe含量中等,而有毒重金属离子Cu、Ni、Pb、Cd、Cr含量很低;无论是凝胶还是全叶中,海水浓度对库拉索芦荟中Ca、Mn元素的影响很大,对其他各种元素的影响不大,但Cd离子的含量随海水灌溉浓度的升高呈略微上升趋势。     

微波消解-电感耦合等离子体质谱法同时测定雄蚕蛾中8种元素

目的 建立微波消解-电感耦合等离子体质谱(inductively coupled plasma mass spectrometry, ICP-MS)法同时测定雄蚕蛾中钠、锰、镁、铜、钙、铁、硒和锌8种元素的含量的方法。方法 样品经硝酸-过氧化氢微波消解后, 通过在线加入内标溶液校正, 以72Ge为内标, 采用ICP-MS测定雄蚕蛾中钠、锰、镁、铜、钙、铁、硒和锌8种元素的含量。结果 8种元素线性良好, 相关系数为0.9995~0.9999; 钠、锰、镁、铜、钙、铁、硒和锌的检出限分别为0.04、0.0004、0.003、0.003、0.01、0.004、0.0005、0.006 mg/kg; 8种元素的回收率在91.3%~98.6%之间, 相对标准偏差(relative standard deviation, RSD)≤3.7%(n=6)。结论 该方法灵敏度高、稳定性好, 可以满足雄蚕蛾中钠、锰、镁、铜、钙、铁、硒和锌的同时测定。     

电感耦合等离子体质谱法同时测定马鹿皮中9种元素

目的建立微波消解-电感耦合等离子体质谱(inductively coupled plasma mass spectrometry,ICP-MS)法同时测定马鹿皮中钠、锰、镁、钾、钙、铁、硒、铜和锌9种元素的含量的方法。方法样品经硝酸-过氧化氢微波消解后,通过在线加入内标溶液校正,以72Ge为内标,采用ICP-MS测定马鹿皮中钠、锰、镁、钾、钙、铁、硒、铜和锌9种元素的含量。结果 9种元素线性良好,相关系数为0.9995~1.0000;钠、锰、镁、钾、钙、铁、硒、铜和锌的检出限分别为4、0.007、0.2、1、1、0.3、0.004、0.009、0.05 mg/kg;9种元素的回收率在86%~116%之间;相对标准偏差(relative standard deviation,RSD)≤7.2%(n=6)。结论该方法灵敏度高、稳定性好,可以满足马鹿皮中钠、锰、镁、钾、钙、铁、硒、铜和锌的测定。     

Influence of pH,concentration of sodium lactate as an additive and ultrasonic treatment on synthesis of zinc phosphate white pigments

Zinc oxide that has the photocatalytic activity is used as a white pigment for cosmetics. A certain degree of sebum on the skin is decomposed by the ultraviolet radiation in sunlight. In this work, zinc phosphates were prepared from zinc nitrate and phosphoric acid at pH 5 and 7 with and without the addition of sodium lactate and ultrasonic treatment as a novel white pigment for use in cosmetics. The chemical composition, powder properties, photocatalytic activity, colour phase, moisture retention and smoothness of the zinc phosphates were studied. The obtained materials had a Zn/P ratio of about 1.5, which corresponds to zinc orthophosphate Zn₃(PO₄)₂. Samples prepared with ultrasonic treatment indicated the high ratios of large particles in scanning electron microscopy images and particle‐size distributions. The photocatalytic activity of these zinc phosphate particles was too less to protect the sebum on the skin. The materials obtained and their thermal products at 100°C showed a high reflectance within the range of visible light. The slipping resistance and roughness of the powder were enough low for use in cosmetics.     

ICP-AES次灵敏线法测定高盐食品中氯化钠的含量

本文以高盐食品为研究对象,建立了运用等离子体发射光谱法(ICP-AES)次灵敏线(330.232 nm)检测高盐食品中NaCl含量的方法,并比较了外界共存离子以及不同前处理方法对于测定结果的影响。结果显示:ICP-AES次灵敏线(330.232 nm)的线性范围(10~300 mg/L,r=0.9995)宽于主灵敏线(589.59 nm)的线性范围(0~20 mg/L,r=0.9998)且精密度良好(RSD < 1.0%),可以规避传统方法测定样品因稀释梯度大而导致的误差;外界共存元素K、Ca、Mg、Sn及Zn离子对于ICP-AES发射光谱次灵敏线测定NaCl含量的结果没有影响,这也规避了滴定法中非目标氯化物带来的干扰;通过与国标方法的比较,ICP-AES发射光谱次灵敏线法的准确性与精密度均与国标法持平,这表明ICP-AES发射光谱次灵敏线在高盐食品中检测氯化钠含量的具有独特优势,具有一定的推广价值。     

固定化酵母在糯米稠酒中的应用

以海藻酸钠为载体，以CaCl2和ZnSO4为交联剂制作固定化酵母，并将其应用于糯米稠酒的连续发酵。研究结果表明，当海藻酸钠溶液浓度为2．5，以CaCl2溶液为交联剂制备的固定化酵母，应用于糯米稠酒生产的效果较好。连续发酵5批，所得糯米稠酒米香、醇香浓酸甜适中，酒体醇厚，无苦涩味。     

Development of functional alginate fibers for medical applications

In this study, antibacterial alginate fibers were developed by using two approaches for fiber development. Firstly, replacing the sodium ions of sodium alginates with metal ions like zinc. Secondly, replacing the sodium ions of sodium alginate with biologically inactive ions like calcium and loading the fibers with ZnO nanorods. Fibers were characterized by liquid absorption and ion release measurements, by placing them separately in distilled water, solution A (0.8298% NaCl & 0.0368% CaCl2) and normal saline solution. Results showed that release of ions from fibers was affected by liquid absorption, physiology of solution and contact time with solution. More ions were released from fibers with higher absorption and longer contact time. Calcium alginate fibers containing zinc ions showed greater absorbency as well as the greater metal ions release. Fibers containing zinc ions, and ZnO nanorods were also tested for their mechanical properties and antibacterial properties against Staphylococcus aureus and Escherichia coli. Alginate fibers containing ZnO nanorods were stronger than alginate fibers containing zinc ions. However, calcium fibers containing zinc ions exhibited more antibacterial activity.