肝脏含铁提取物的制备及对Caco-2细胞吸收铁的促进作用

以新鲜猪肝脏为原料,采用中性蛋白酶和风味酶两步水解工艺制备肝脏含铁提取物,经喷雾干燥的提取物粉末的铁含量约为475.3μg/g,且溶解性良好。采用Caco-2细胞作为铁吸收的评价模型,与无机铁FeCl3溶液比较,该含铁提取物粉末具有显著促进铁吸收的作用。这为研究生物利用度高、易于吸收的有机铁提供了一种新来源。      

肝脏含铁提取物的制备及对Caco-2细胞吸收铁的促进作用

以新鲜猪肝脏为原料,采用中性蛋白酶和风味酶两步水解工艺制备肝脏含铁提取物,经喷雾干燥的提取物粉末的铁含量约为475.3μg/g,且溶解性良好.采用Caeo-2细胞作为铁吸收的评价模型,与无机铁Fecl3 溶液比较,该含铁提取物粉末具有显著促进铁吸收的作用.这为研究生物利用度高、易于吸收的有机铁提供了一种新来源.     

利用啤酒酵母泥制备酵母多糖铁补剂

本文探讨了利用啤酒酵母泥进行有机补铁剂的研究.研究以苯酚硫酸法测定多糖含量,通过碱提法,酶解法,微波法提取酵母多糖的比较,最终确定以碱提法提取酵母多糖,并与三氯化铁在碱性条件下合成酵母多糖铁.研究所得酵母多糖铁呈深棕红色无定形粉末,易溶于水,得率为26.63％;以邻菲罗啉比色法测定酵母多糖铁的铁含量显示含铁量为17.7％.本研究所得的酵母多糖铁将有可能是一种新型的补铁剂.     

红肉可保持精力充沛

如今非常推崇素食主义,而肉类,尤其是红肉,如猪、牛、羊肉却成了不受欢迎的食物,每天仅吃些蔬菜水果和米饭,长此以往相信朋友们肯定有这样的体会:人特别容易疲劳、精力涣散,这就是长期拒绝肉类,特别是红肉的慢性后果。这看似颇为奇怪,其实一点也不足为怪:肉类太少的膳食无法为人体提供足够的铁元素,很容易让人觉得累和疲倦。而猪、牛、羊肉等红肉却含有丰富的血红素铁,这对保持人体的充沛精力相当重要。正常成人体内含铁3-5克,其中60%-70%存在于血红蛋白中,3%在肌红蛋白中,细胞色素酶、过氧化氢酶等酶系统中约占1%,其余约26%-36%以铁蛋白或含铁血黄素的形式贮存于肝、脾、骨骼等处。机体缺铁会出现缺铁性贫血,表现为食欲减退、乏力、面包苍白、心悸、头晕等。铁的食物来源为含血红素铁丰富的动物性食品,     

铁的生理功能与吸收

铁缺乏所引起的缺铁性贫血仍是 目前世界性的一大营养问题。铁是人体所需的最重要的微量元素之一,也是体内含量最多的一种必需微量元素。成人体内含铁约3—5克,其中的60—70％存在于血红蛋白中,3％在肌红蛋白中,各种酶系统中的铁不足1％,余下的26—36％以运铁物质和铁储备的形式存在。铁是血红蛋白分子的重要组成,血红蛋白分子可以吸收肺中的氧气,随血流将氧带     

铁与人体健康

铁是人体必需的微量营养素之一,虽只占人体体重的0.006%,即成人含铁约4.0g左右,但极为重要。人体内的铁都与蛋白质结合,无游离态。铁是血红蛋白、肌红蛋白和许多酶的构成成分,成人体内的总铁量为4～5g,其中72%的铁结合在能携带氧分子的血红蛋白和运铁蛋白(血浆)中,以血液形式流经全身;3%以肌红蛋白的形式存在,又叫功能铁;其余则为储备铁,以铁蛋白和含铁血黄素的形式存在于肝、脾、骨髓、骨骼肌、肠粘膜、肾等组织中。铁在体内可反复利用,健康成人每日只需吸收1mg以上的铁即可满足机体需要。一、铁的生理功能(一)造血和输氧铁对人体健康的重…     

提汁过程蔗汁铁和酚类色素含量对色值影响的研究

测定研究甘蔗提汁过程各座次压榨机出汁以及典型蔗汁中铁、酚类色素含量和色值,分析蔗汁增色因素的变化规律及致因。结果表明,提汁过程榨出汁色值与蔗汁中铁和酚类色素含量显著相关。不同厂同列榨机出汁含铁量随榨机座次增加,前三座榨机蔗汁酚类色素含量递增;两家糖厂初压汁含铁量分别为54.0和220.1μg/mL·○Bx,初压汁酚类色素含量分别为3021和1791mg/kg·○Bx;前五座榨机蔗汁色值随榨机座次明显升高。预灰对铁的去除效果不明显,对酚类色素的去除较明显,预灰后蔗汁色值有所降低。     

影响人体铁吸收的因素

营养调查结果显示,我国人民膳食中的铁含量充足,城乡分别达到RDA的183％和173％,但缺铁性贫血仍十分常见,占整个人群的20％左右。问题就在于我国的膳食以植物性食物为主,铁吸收率很低。因此,有必要进一步研究影响人体铁吸收利用的因素。 1 人体内铁的存在形式 成人体内含铁约3～5g。主要存在于2大类物质中:①以特定的生理功能的形式存在于血红蛋白(Hb)、肌红蛋白及一些酶系统中。它们的作     

酒类

含铁葡萄酒的制造方法 铁是构成血红肮的一种主要元素。含铁化合物可以用来作为贫血治疗剂及补血剂。人体主要吸收Fe~(2+),而不能吸收Fe~(3+),且有机含铁化合物(铁与     

可增加食品含铁量的单质铁粉

单质铁粉被广泛用于增加谷类食品含铁量，是添加于家用面粉、调制食品和方便面中唯一的一种铁制品，也是添加在玉米粉、糕点、甜饼、饼 干和许多婴儿谷类食品和方便早餐谷类食品等最常用铁制品，单质铁粉所提供铁约占美国人饮食中所需铁含量15％，约占加拿大人饮食中所需铁含量20％。     

Immobilization of selenite on Fe3O4 and Fe/Fe3C ultrasmall particles

The sorption of selenite ions onto Fe3O4 and Fe/Fe3C nanoparticles (NPs) was studied in aqueous solutions under anoxic conditions using gamma spectrometry and X-ray absorption spectrometry (XAS) techniques. This is the first study related to the remedial applications of Fe/Fe3C NPs. FesO4 NPs have been prepared by conventional coprecipitation of Fe(II) and Fe(III) in basic solutions. Stable Fe/Fe3C NPs have been prepared by Fe(CO)5 sonicating in diphenylmethane solutions and subsequently annealing the as-prepared product. Kinetic study demonstrated that Se(IV) sorption is extremely rapid: the equilibrium is reached in approximately 10 and 30 min for Fe3O4 and Fe/Fe3C NPs, respectively, at pH = 4.9-5.1 in solutions of 0.1 M NaCl. The distribution coefficients are also very high for both kinds of NPs (Kd > 3000). Increasing the pH to 10.3 or adsorption of organic ligands, like L-lysine or dodecanoate, at the surface of NPs causes the decrease in Kd values. However, even in these cases Kd values exceed 150. Magnetic NPs loaded with selenium can be easily and completely removed from solution with a 0.4 T permanent magnet. XAS study revealed the absence of Se(IV) reduction during the sorption onto Fe3O4 NPs in the pH range of 4.8-8.0. By contrast, the removal of Se(IV) with Fe/Fe3C NPs in anaerobic conditions occurs via Se(IV) reduction to Se(-II) and subsequent formation of iron selenide at the particle surface. Thus, the Fe/Fe3C NPs are superior to Fe3O4 NPs due to their ability to immobilize rapidly and irreversibly Se(IV) via reductive mechanism. Presumably these particles could be also effective for the removal of other contaminants such as hexavalent chromium, actinides, technetium, and toxic organic compounds.     

Pd-Fe合金电镀

概述了含有可溶性Pd化合物,可溶性Fe化合物,导电盐和光亮剂等组成的Pd-Fe合金镀液,可以获得耐蚀性,耐磨性和附着性优良的白色光亮Pd-Fe合金镀层,不会发生金属过敏反应,适用于装饰品的表面精饰.     

果酒中铁的测定

果酒中铁含量过高不但影响果酒的颜色和口味，还容易产生沉淀而影响其感官指标。铁的化合物有二价和三价两种状态，而人体能够吸收利用的是二价铁，将二价铁和三价铁分离，分别测定。一方面可以了解果酒中铁是否超标，另一方面可以了解其对人体的生理意义。     

铁（Ⅲ）——PAN—S体系分光光度法测定抗坏血酸

基于抗坏血酸还原Fe(Ⅲ）-1-（2-吡定偶氮）-2-萘酚-6-磺酸[简写为Fe(Ⅲ）-PAN-S]为Fe(Ⅱ）-PAN-S,建立了分光光度法测定水果中抗坏血酸的方法。在pH4.5的HAc--NaAc缓冲溶液中,Fe(Ⅱ）-PAN-S络合物的最大吸收峰位于549nm和748nm处。在748nm处,抗坏血酸含量在0-100μg/25ml）范围内符合比耳定律,方法操作简便,选择性较高,可用于水果中抗坏血酸的测定。     

Effects of metal ions (Cu,Fe and Fe) on HPLC analysis of catechins

Catechins [(−)-epicatechin (EC), (−)-epigallocatechin (EGC), (−)-epicatechin gallate (ECG) and (−)-epigallocatechin gallate (EGCG)] were analysed by HPLC using an ODS column, an electrochemical detector (0.75 V vs. Ag/AgCl) and an eluting solvent composed of water containing buffer (84% v/v), acetonitrile (12% v/v) and ethylacetate (4% v/v) in the presence of metal ions (Cu²⁺, Fe²⁺ and Fe³⁺). HPLC peaks were affected by metal ions: the peak intensities of ECG and EGCG decreased, but the peak intensities of EC and EGC were not affected seriously. Fe²⁺ most markedly decreased the peak intensities of EGCG. EDTA was added to mask metal ions and an optimum condition was proposed. The effects of the metal ions on HPLC analysis are discussed from the viewpoints of metal complex formation with catechins and oxidation of catechins on the basis of ultraviolet–visible (UV–vis) spectrophotometry, electrospray ionisation mass spectrometry (ESI-MS) and cyclic voltammetry (CV).     

浅谈白酒中铁含量的测定

白酒中铁离子的含量国家标准中没有规定 ,也没有具体的检验方法。但是 ,如果含量超过 2ｍｇ/Ｌ时 ,就可能引起酒体变黄甚至产生棕褐色沉淀 ,影响白酒的质量。白酒中铁的来源主要是酿酒用具的铁材剥蚀、操作及运输工具的铁材接触、贮酒容器的传入以及水等。酒中的铁与空气隔绝时 ,是二价的 ,可溶性的。但有空气之后 ,氧气将铁氧化成三价。如果酒度很低时 ,能使酒体色泽变深或产生混浊。经我厂长期实践 ,总结出了一套简便易行的测铁方法。该方法的特点是 :简便 ,即不需消化过程 ;快速 ,即半小时可得出结果 ;准确 ,误差小 ;易行 ,只用分光光度…     

面粉中加铁改善居民缺铁性贫血的可行性研究

缺铁性贫血是一种常见的营养缺乏病,全世界约２１．５亿人患有不同程度的铁缺乏。我国最新调查显示,１８～６０岁人群中贫血患病率占２５％,学龄前儿童患病率为２３．３５％。１９９７年国务院批准颁布的《中国营养改善行动计划》公开承诺：“要使孕妇和儿童的缺铁性贫血患病率较１９９０年降低１／３”。解决缺铁性贫血的问题已摆在全社会,特别是营养工作者面前。本文以营养教育和空白对照考核面粉中加铁对贫血的防治作用。 一、资料与方法 （一）确定干预社区 采用整群抽样的方法,随机选取莘县燕店乡６个村作为试验点,按各村的地理…     

Effects of Fe(III) chemical speciation on dissimilatory Fe(III) reduction by Shewanella putrefaciens

Shewanella putrefaciens, a heterotrophic member of the gamma-proteobacteria is capable of respiring anaerobically on Fe(III) as the sole terminal electron acceptor (TEA). Recent genetic and biochemical studies have indicated that anaerobic Fe(III) respiration by S. putrefaciens requires outer-membrane targeted secretion of respiration-linked Fe(III) reductases. Thus, the availability of Fe(III) to S. putrefaciens may be governed by equilibrium chemical speciation both in the solution phase and at the bacterial cell-aqueous or cell-mineral interface. In the present study, effects of Fe(III) speciation on rates of bacterial Fe(III) reduction have been systematically examined by cultivating S. putrefaciens anaerobically on a suite of Fe(III)-organic complexes as the sole TEA. The suite of Fe(III)-organic complexes spans the range of stability constants normally encountered in natural water systems and includes Fe(III) complexed to citrate, 5-sulfosalicylate, NTA, salicylate, tiron, and EDTA. Rates of bacterial Fe(III) reduction in the presence of dissolved chelating agents correlate with the thermodynamic stability constants of the Fe(III)-organic complexes, implying that chemical speciation governs Fe(III) bioavailability. Equilibrium Fe(III) sorption experiments measured the reversible coordination of Fe(III) with S. putrefaciens as a function of cell/Fe(III) concentration, time, and activity of competing chelating agents. Results show that S. putrefaciens readily sorbs dissolved Fe(III) but that adsorption is restricted by the presence of strong Fe(III)-chelating agents. Our results indicate that dissimilatory Fe(III) reduction by S. putrefaciens is controlled by equilibrium competition for Fe(III) between dissolved organic ligands and strongly sorbing functional groups on the cell surface.     

铁营养保健酱油研制

本文从补铁重要性入手，探讨了在酱油中强化铁的可行性及铁强化剂的选择，通过对比试验，从强化铁后酱油色、香、味、体及稳定性等方面得出最佳铁强化剂及其用量。