螺旋藻多糖铁(Ⅲ)配合物的制备、抗氧化及淋巴细胞增殖活性

以三氯化铁为原料,通过络合反应,对螺旋藻多糖(SP)进行结构修饰,制得有机铁化合物〔螺旋藻多糖铁(Ⅲ)配合物SP-Fe(Ⅲ)〕。采用FTIR、DSC、TGA、XRD和SEM对其结构进行了表征,采用DPPH(1,1-二苯基-2-三硝基苯肼)自由基法、羟自由基法等5种方法和MTT(四唑盐)法分析了SP和SP-Fe(Ⅲ)的抗氧化活性和淋巴细胞增殖活性的影响。制备的SP-Fe(Ⅲ)中Fe(Ⅲ)质量分数为16.42%±1.17%。采用5轴蛛网图对SP-Fe(Ⅲ)的抗氧化活性进行了综合评价。结果表明,SP-Fe(Ⅲ)相比SP具有较高的抗氧化活性。在模拟人工胃液消化后,随着消化时间的延长,在pH=6.8的人工肠液中释放出的Fe(Ⅲ)质量分数达到83.64%;在31.25×10–3 g/L的质量浓度下,与SP相比,SP-Fe(Ⅲ)配合物对淋巴细胞增殖提高了44.35%。     

氨基酸铜配合物的抗氧化活性分析

采用氨基酸和醋酸铜为原料,设计合成4种不同配体结构的Cu(Ⅱ)金属配合物Cu L1~4,并用紫外分光光度计和傅里叶红外检测仪对其化学结构进行了分析。采用改进的氮蓝四唑还原法确定了氨基酸铜金属配合物抗氧化活性最强时对应的浓度,并讨论了在相同浓度下不同种类氨基铜酸配合物的抗氧化活性与其化学结构之间的关系。结果表明,L-α-丙氨酸铜配合物由于金属活性中心周围空间位阻较小,其抗氧化活性高于苯丙氨酸铜配合物。     

壳寡糖席夫碱Cu(Ⅱ)配合物的制备、表征、电化学行为及抗氧化活性

在无水乙醇中,对羟基苯甲醛与壳寡糖直接反应得到希夫碱化合物,并以此为配体合成了它与Cu~(2+)以不同摩尔配比的配合物,通过元素分析、红外光谱、紫外―可见吸收光谱和差热―热重对这些化合物进行了结构性能的表征。此外,研究了希夫碱及配合物的抗氧化活性。结果表明,希夫碱的-C=N中氮原子、酚羟基中氧原子、伯仲羟基中氧原子均参与配位。循环伏安结果表明了生成的配合物具有电化学活性,在扫描速率为0.025~1.0 V/s范围内,配合物在玻碳电极上的反应主要由扩散过程控制。对超氧负离子自由基和羟自由基的清除能力依次为Schiff-Cu13>Schiff-Cu11>PCS,Cu~(2+)含量与希夫碱配合物的抗氧化活性有关。     

尿素铁（Ⅲ）配合物的合成研究

硝酸铁和尿素在无水乙醇溶剂中合成了尿素铁（Ⅲ）配合物。通过单因素实验考察物料配比、反应温度、乙醇含量、反应时间、搅拌速率对尿素铁（Ⅲ）配合物收率的影响。实验结果表明最佳的工艺条件为：Fe（NO3）·9H2O和尿素物料配比为1∶6,反应温度为50℃,溶剂用无水乙醇,反应时间为2h,搅拌速率为300r·min^-1。在此条件下得到的尿素铁（Ⅲ）配合物收率为82.25%。     

大黄素-硒(Ⅳ)配合物的合成、表征及抗氧化活性研究

研究了大黄素-硒(Ⅳ)配合物的合成,并对比配体和配合物体外抗氧化活性。采用单因素试验和正交试验研究大黄素-硒(Ⅳ)配合物的最佳合成条件:以无水乙醇为溶剂、n(大黄素)∶n(四氯化硒)=1∶2、pH 3～4、反应温度40～45℃。通过红外光谱法、紫外-可见光谱法和基质辅助激光解吸-飞行时间质谱对大黄素-硒(Ⅳ)配合物的结构进行表征;运用紫外-可见分光光度法测定配体和配合物对DPPH的清除率。结果显示,大黄素-硒(Ⅳ)配合物抗氧化活性相对于配体大黄素有显著提高,大黄素与硒之间存在协同抗氧化作用。     

改性香菇多糖铁(Ⅲ)配合物的制备及其应用研究

采用95%乙醇对香菇粉进行脱脂预处理后,再用超声波法提取香菇多糖(LNT)。为提高其水溶性,采用过氧化氢氧化法对提取的香菇多糖进行化学改性。探究了过氧化氢浓度、pH值、改性时间等因素对改性香菇多糖(MLNT)水溶性的影响。利用傅里叶变换红外光谱和X射线粉末衍射技术对改性香菇多糖进行了结构表征。结果表明,改性后香菇多糖的分子结构发生改变,其水溶性以及与Fe(Ⅲ)的配位能力增强。采用共振散射技术研究了改性香菇多糖与三价铁离子的配位作用,并考察了反应介质、pH值、改性多糖用量等因素的影响。在最优实验条件下,在0.40~6.0μg/mL范围内,体系的共振散射强度变化值ΔI与Fe(Ⅲ)浓度之间有一定的线性关系,其检出限为0.81 ng/mL。据此,分别分析测定了矿渣和布袋灰中的铁含量,相对标准偏差为3.8%和3.4%,回收率为102%和112%。     

酞酸二丁酯在铁(Ⅲ)-草酸盐配合物体系中的光降解

在铁(Ⅲ)-草酸盐配合物体系中考察pH值,铁(Ⅲ)／草酸盐(Fe(Ⅲ)／Ox)配比,酞酸二丁酯(DBP)初始浓度对DBP光降解的影响,结果表明pH=3．5和Fe(Ⅲ)／Ox配比为10．0／120．0μmol／L时具有较强的氧化能力,其光解反应符合表观一级反应动力学规律。并且利用气相色谱-质谱联机分析确定DBP光降解得中间产物,揭示DBP光降解的主要反应途径是OH自由基提取烷基上与羧基相连的α-H,生成醇(ROH),再分解成为酞酸和二醇,进一步氧化脱羧,直至矿化。     

铁配合物的合成、性质及应用

我国因为土地广阔,人口分布不均,居民营养意识薄弱,膳食结构单一,主要以面食、蔬菜为主要营养源,致使我国的缺铁性贫血患病率远高于国外发达国家.所以合成新型补铁剂具有重要意义.主要论述以固相熔融法合成氨基酸类铁配合物——甘氨酸亚铁.利用元素分析确定其化学式,并对其结构进行表征分析,后构建甘氨酸亚铁对治疗缺铁性贫血小白鼠的效...     

木犀草素-锌（Ⅱ）配合物的制备及清除自由基活性研究

为增强木犀草素的生物活性将其制成锌（Ⅱ）配合物,采用了紫外、红外、元素分析及核磁共振1H谱的方法对配合物进行了结构表征,并测定了该配合物的稳定常数。抗氧化性试验采用了DPPH·法和水杨酸法分别测定了木犀草素-锌（Ⅱ）配合物对（DPPH·）自由基和羟自由基（·OH）的清除作用。结果表明：木犀草素的5OH～4C=O和一个锌离子发生配位形成木犀草素-锌（Ⅱ）配合物;该配合物比较稳定,稳定常数为：βn=4.03×10^7;木犀草素锌（Ⅱ）配合物能有效清除DPPH·和·OH自由基,其清除能力均强于木犀草素,对DPPH·自由基的清除作用略高于Vc,对·OH自由基的清除作用与Vc相接近,最大清除率分别为89.37%和85.10%,说明木犀草素-锌（Ⅱ）配合物是一种较强的自由基清除剂。     

铁配合物及价态分析的光谱电化学研究

用ＦＯＳＥＣＳ分别研究了２，２－联吡啶铁，硫氰酸铁，酒石酸铁配合物的光谱电化学特性，求算了它们的热力学函数及条件平衡常数，并对混合溶液中Ｆｅ＾３＋的价态分析进行了初步探讨。     

Preparation and the antioxidant and antibacterial activities of urushiol powders (YPUOH)

Lacquer sap derived from lacquer trees has been widely used in Asian countries for thousands of years as a natural paint and coating material. These natural lacquers exhibit superior barrier properties against oxygen and water, as well as good durability, chemical resistance, mechanical properties, and antibacterial and antioxidant properties. However, they are limited in commercial application due to their high volatility, low drying rate, and allergic reactions. To overcome these limitations, powder-type urushiols (YPUOH), which are essential to provide convenient handling, were successfully prepared using urushiol and different contents of 3-(trimethoxysilyl) propyl methacrylate (TPM). The prepared YPUOH powders were analyzed by Fourier-transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), thermogravimetric analyzer (TGA), and antibacterial and antioxidant measurements. The as-prepared YPUOH powders exhibited excellent antibacterial activity against E. coli and S. aureus, good antioxidant activity, and high thermal stability.     

Chemo‐enzymatic synthesis of lipophilic ferulates and their evaluation for antioxidant and antimicrobial activities

An efficient chemo‐enzymatic synthesis of ferulic acid‐based structured lipids mimicking triacylglycerol with a pendant phenolic moiety was carried out for the first time. Initially, ferulic acid was reduced to coniferyl alcohol, followed by its esterification with fatty acids. The key step in the synthesis was dihydroxylation of the olefinic side chain of coniferyl ester, which was eventually esterified with fatty acids to generate phenolic structured lipids. Two such compounds of varying fatty acid chain lengths were synthesized in good yield. Structural confirmation of both compounds is based on IR, ¹H and ¹³C NMR, and MS techniques. The synthesized compounds were tested for in vitro antioxidant and antimicrobial activities. Both compounds exhibited moderate to good antioxidant activity. The phenolic structured lipid with only shorter‐chain fatty acids showed antibacterial activity. Both compounds did not show any antifungal activity.     

琼榄提取物的抗氧化及抗菌活性初步研究

为研究琼榄的药用活性成分,更好地开发和利用琼榄资源,对琼榄根、茎、叶的5种不同溶剂提取物分别采用清除DPPH自由基法和滤纸片扩散法进行抗氧化及抗菌活性研究。结果表明,琼榄叶的乙酸乙酯提取物（L-EtOAc）清除DPPH自由基的IC50最小,为154.1μg/mL,是15组提取样品中清除自由基活性最强的部位。琼榄根、茎、叶的15组提取物对5种供试菌均具有不同程度的抑菌活性,且以琼榄叶的乙酸乙酯提取部位对5种供试菌的抑菌作用均较强,特别是对金黄色葡萄球菌、大肠杆菌、铜绿假单胞菌的抑制作用和阳性对照品头孢他啶的抑菌作用接近。因此,琼榄叶部位的抗氧化和抗菌活性最强,且活性物质在乙酸乙酯部位,L-EtOAc为有效提取部位。     

3-羟基-4-吡啶酮衍生物的合成及与Fe3+螯合性能

以甲基麦芽酚、对苯二胺、丙二酰氯为主要原料,微波辅助合成得到N,N'-二[对-(2-甲基-3-羟基-4-吡啶酮)苯基]丙二酰胺。采用IR、1HNMR、UV-vis、MS对产物结构进行了确证。采用分光光度法测定了该化合物对Fe3+的螯合性能,结果表明,在pH=7.40的Tris-水-乙醇缓冲溶液中,配体与Fe3+的配位比为1∶1,配合物表观稳定常数为lgK=7.76,证实该化合物对Fe3+具有潜在的螯合能力。     

Synergistic effect of BSA on antioxidant activities in model food emulsions

Sunflower oil-in-water emulsions containing TBHQ, caffeic acid, epigallocatechin gallate (EGCG), or 6-hydroxy-2,5,7,8-tetramethylchroma-2-carboxylic acid (Trolox), both with and without BSA, were stored at 50 and 30°C. Oxidation of the oil was monitored by determination of the PV, conjugated diene content, and hexanal formation. Emulsions containing EGCG, caffeic acid, and, to a lesser extent, Trolox were much more stable during storage in the presence of BSA than in its absence even though BSA itself did not provide an antioxidant effect. BSA did not have a synergistic effect on the antioxidant activity of TBHQ. The BSA structure changed, with a considerable loss of fluorescent tryptophan groups during storage of solutions containing BSA and antioxidants, and a BSA-antioxidant adduct with radical-scavenging activity was formed. The highest radical-scavenging activity observed was for the isolated protein from a sample containing EGCG and BSA incubated at 30°C for 10 d. This fraction contained unchanged BSA as well as BSA-antioxidant adduct, but 95.7% of the initial fluorescence had been lost, showing that most of the BSA had been altered. It can be concluded that BSA exerts its synergistic effect with antioxidants because of formation of a protein-antioxidant adduct during storage, which is concentrated at the oil-water interface owing to the surface-active nature of the protein.     

Effects of three conventional drying methods on the lipid oxidation,fatty acids composition,and antioxidant activities of walnut (Juglans regia L.)

Three walnut (Juglans regia L.) drying methods (sun drying, direct oven drying, and intermittent oven drying) were employed, and the consequent changes in lipid oxidation attributes, such as acid value (AV), peroxide value (POV), saponification value (SV), fatty acid composition, and antioxidant activity [including reducing power, superoxide anion scavenging activity, 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity (DPPH), lipoxygenase (LOX) activity, total phenols content (TPC), and total flavonoids content (TFC)] were investigated in this study. Sun drying resulted in the highest AV, POV, and SV, followed by direct oven drying and intermittent oven drying. Antioxidant activities and related compounds, TPC and TFC, were initially increased and then declined during drying, and a significant correlation was found between antioxidant activity and TPC and TFC. The LOX activities of all samples showed an increasing trend, although those of the sun-dried samples were the lowest. The walnuts dried with the intermittent oven drying method contained more linoleic acid than those dried by direct oven drying. Overall, intermittent oven drying appears to be a promising strategy for fresh walnut drying.     

新型固体铁系复合盐催化剂制备及其催化酯化研究

报道新型固体复合盐催化剂（Ⅱ）的制备，应用5种催化剂分别进行催化乙酸和乙醇合成乙酸丁酯的对比试验，选出优良催化剂（Ⅱ）并进行催化酯化合成了18种酯的研究工作。通过实验证明催化剂（Ⅱ）酯化性能优良（优于固体超强酸Fe2O3/SO4^2-),操作简单，污染小。在18种酯中乙酸丁酯的产率高达97．9％。     

Supercritical fluid extracts with antioxidant and antimicrobial activities from myrtle (Myrtus communis L.) leaves. Response surface optimization

Supercritical Fluid Extraction (SFE) was used to obtain myrtle leaf extracts, and to study the antioxidant capacity (AOC) and in vitro antimicrobial activity of those extracts. To optimize the SFE operational conditions, the response surface methodology (RSM) was adopted. The parameters studied were: pressure (P), within the range 10 to 30 MPa; temperature (T), between 35 °C and 60 °C and supercritical carbon dioxide (SCCO₂) flow rate (Q) within the range 0.15 to 0.45 kg h⁻¹. The results show a good fit to the proposed model and the optimal conditions obtained (23 MPa, 45 °C, and SCCO₂ flow rate of 0.3 kg h⁻¹) were within the experimental range. The predicted values agreed with experimental ones, thus indicating the suitability of the RSM model for the optimization of the extraction conditions being investigated. With those values remaining constant, ethanol as a co-solvent was then studied. There was an observed rise in AOC as the amount of ethanol increased, within the range studied (0–30 wt% ethanol). The extract with the highest AOC was tested for its antimicrobial activity against gram-positive and gram-negative bacteria. The minimum inhibitory concentration (MIC) values obtained showed significant inhibitory effect against gram-positive bacteria.