食品中铬的生理功能及其检测方法

介绍了铬的物理化学性质;铬的生理功能主要是铬在糖代谢和脂肪代谢方面的作用;食品中的铬的含量的测定方法;铬作为一种必需微量元素,其保健功能倍受关注.     

部分微量元素对基因组结构稳定性影响

维持基因组结构稳定性是生物生存的基础,微量元素作为人体生长发育所必需的营养成分,其摄入对于维持染色体和DNA结构的稳定具有重要的作用。本文介绍了锌、硒、铜、铁、铬等微量元素对基因组结构稳定性的影响,并就微量元素对基因组结构稳定性的影响机制作了介绍。     

富集微量元素的功能酵母研究概况及应用前景

微量元素是生物有机体必需的营养元素,在维持生物体的正常代谢过程中起着重要作用。富集微量元素的功能酵母能将无机态微量元素转化为有机态微量元素,以提高其生物利用率;其自身含有丰富的营养成分,很适合作为饲料添加剂应用在畜牧业中。文中综述了几种富集微量元素的功能酵母——富硒酵母、富铁酵母、富锌酵母和富铬酵母等的生理功能及其研究概况和富集微量元素的功能酵母在饲料行业中的应用前景。     

膳食中铬对机体健康的影响（综述）

膳食中铬对机体健康的影响（综述）王茂起卫生部食品卫生监督检验所（１０００２１）铬是人体必需的微量元素之一，长期以来铬及其化合物波广泛应用于化工、冶金，皮革和电镀等工业生产上。在我国鉴于工业“三废”的排放对人群健康带来的不利影响．铬作为食品中重要的化学...     

乳酸菌富集微量元素Se、Cr、Zn的初步研究

研究了乳酸菌对硒、铬、锌通过生物转化将无机态微量元素富集转化为细胞内的有机态微量元素。结果表明:适当提高培养基中硒、铬、锌的浓度,有利于乳酸菌的生长和微量元素有机态的富集转化,但是当它们浓度超出一定范围时,则抑制乳酸菌的生长。这3种元素中,乳酸菌对锌的富集转化能力最强,铬次之,而对硒的富集转化能力最弱。     

保加利亚乳杆菌对微量元素硒、铬、锌的富集

硒、铬、锌是人体必需的具有一定功能作用的微量营养元素,有机态微量元素吸收迅速且安全,吸收率高。研究了保加利亚乳杆菌对硒、铬、锌通过生物转化将无机态微量元素富集转化为细胞内的有机态微量元素,结果表明:适当提高培养基中硒、铬、锌的浓度,有利于保加利亚乳杆菌的生长和微量元素有机态的富集转化;但是当硒浓度超出一定范围时,则抑制保加利亚乳杆菌的生长。这3种元素中,保加利亚乳杆菌对锌的富集转化能力最强,铬次之,而对硒的富集转化能力最弱。     

葡萄糖耐量因子(GTF)及作用研究综述

铬作为人体必需微量元素 ,它具有葡萄糖耐量因子的活性 ,因铬缺乏而引起的疾病及铬的生理功能 ;葡萄糖耐量因子定义的变迁、结构推测、生物活性分析方法及争议 ;全文对提取方法及生理临床作用的研究进展状况作一展示 ,以引起更多的科技工作者对这一领域的关注和重视。同时介绍了国内在铬及葡萄糖耐量因子方面所取的主要研究成果及铬在食用饲料方面的作用和安全。     

我国食品中铬污染现状及健康风险

铬是人体必需的微量元素,但摄入过多会对人体产生危害。近年来食品中铬的污染问题引发了人们的关注。本文综述了我国近年来食品中铬污染状况,分析其来源及危害,结合国内外铬的限量标准和风险评估提出相应的措施,为加强食品中铬的研究,确保食品安全提供科学依据。     

含铬废革料资源化 ——制备富铬酵母

简要概述了铬(Ⅲ)作为一种必需微量元素的生理意义,结合制革工业产生大量含铬废革料的事实,提出了利用含铬废革料来制备富铬酵母的资源化新思路。     

粮油食品中微量元素的分析及营养机制的研究

采用了石墨炉及气态氢化物发生原子吸收光谱仪对浙江省27种粮油食品中铜、锌、铁、锰、硒、铬、铅、镉、砷和汞十种微量元素含量水平进行了测试,从而为人类改进膳食结构的观点提供一定依据,结果表明,谷物中的锰、铁、锌、铬、铜含量比较丰富,而在植物性食物中以豆类、花生微量元素含量最高,本文同时对其营养机制进行研究,并从微量元素的角度,论述了食物间微量元素的转化、协同和拮抗作用。以及对微量元素在食品精制过程中的损失也作了一些初步探讨,试验采用标准加入法对分析方法进行考察,回收率为96.3%-104.7%,结果令人满意。     

The role of trace elements for the health of elderly individuals

Elderly individuals have a higher risk to develop trace element deficiencies due to modified dietary habits and requirements, age related physiological changes, drug therapy, and chronic diseases leading to or associated with enhanced consumption or excretion of trace elements. This review gives an overview about the role of zinc, iron, selenium, copper, chromium and fluoride for the health of elderly people in regard of physiological functions, trace element status and intake, and effect of supplementation on clinical parameters and disease outcome.     

The role of trace elements for the health of elderly individuals.

Elderly individuals have a higher risk to develop trace element deficiencies due to modified dietary habits and requirements, age related physiological changes, drug therapy, and chronic diseases leading to or associated with enhanced consumption or excretion of trace elements. This review gives an overview about the role of zinc, iron, selenium, copper, chromium and fluoride for the health of elderly people in regard of physiological functions, trace element status and intake, and effect of supplementation on clinical parameters and disease outcome.     

Chromium, exercise, and body composition

Chromium is an essential trace element involved in the metabolism of carbohydrates, lipids, and proteins mainly by increasing the efficiency of insulin. Chromium deficiency affects the maintenance of normal glucose tolerance and healthy lipid profiles. The Estimated Safe and Adequate Daily Dietary Intake for chromium is 50 to 200 microg/d for adults. However, the dietary intake of chromium in humans is often suboptimal. Chromium assessment has proven to be a challenge due to the low amounts of chromium present in biological materials and the absence of a reliable indicator of chromium status. Recently, chromium has been touted as an agent for increasing lean body mass and decreasing percent body fat. This article reviews the various studies that have been conducted to investigate the relationship of chromium with exercise and body composition.     

Trace elements in flour and bran from common and tartary buckwheat

The contents of Se, Cr, Rb, Zn, Fe, Co, Sb, Ba, Ni, Ag, Hg and Sn were analysed in the flour and bran of common and tartary buckwheat, obtained by milling in a stone mill. In both species most trace elements are concentrated mainly in the bran. However, there are relatively small differences in the contents of iron, antimony, and chromium between flour (extraction rate 55%) and bran fractions. In tartary buckwheat fine flour (extraction rate 42%) there is a lower trace element content than in normal flour. The potential use of buckwheat bran as a dietary source of Zn, and Se, is indicated.     

Assessment of trace element status in humans

Trace elements occur in the body in very small or 'trace' amounts. Deficiencies of essential trace elements produce multiple and diverse clinical signs and symptoms. These may arise from inadequate dietary intake, decreased bioavailability, iatrogenic factors, certain disease states in which decreased absorption, excessive excretion and/or utilization occurs, and physiological states in which trace element requirements are increased and/or body stores are reduced. This review discusses both the static and functional laboratory tests used for the assessment of chromium, copper, selenium, and zinc status in humans, with emphasis on those tests suitable for community use. Static tests measure the total quantity of the trace elements in various accessible tissues and body fluids such as hair, nails, blood or some of its components, and urine; functional tests measure the activity of trace-element-dependent enzymes, or a physiological or behavioural function dependent on a specific trace element. The advantages and limitations of each test are discussed, together with the effects of non-nutritional factors that may confound the interpretation of the results. Interpretive criteria are also given, where possible.     

Nutritional Assessment of Processing Effects on Major and Trace Element Content in Sea Buckthorn Juice (Hippophaë rhamnoides L. ssp. rhamnoides)

ABSTRACT:  Processing effects on the mineral content were investigated during juice production from sea buckthorn ( Hippophaë rhamnoides L. ssp . rhamnoides, Elaeagnaceae) using berries from 2 different growing areas. The major and trace elements of sea buckthorn berries and juices were determined by atomic absorption spectroscopy (AAS)—(calcium, iron, magnesium, potassium, sodium) and inductively coupled plasma–mass spectrometry (ICP-MS)—(arsenic, boron, chromium, copper, manganese, molybdenum, nickel, selenium, zinc). Potassium is the most abundant major element in sea buckthorn berries and juices. The production process increased the potassium content in the juice by about 20%. Moreover, the processing of juice increased the value of manganese up to 32% compared to the content in berries. During industrial juice production, the technological steps caused a loss of about 53% to 77% of the chromium concentration, 50% of the copper content, 64% to 75% of the molybdenum amount, and up to 45% of the iron concentration in the final juice product. Consumption of sea buckthorn juice represents a beneficial source of chromium, copper, manganese, molybdenum, iron, and potassium for the achievement of the respective dietary requirements.     

氨基酸微量元素螯合物替代无机微量元素对肉鸡饲养效果的影响

研究氨基酸微量元素螯合物替代饲粮中无机微量元素对肉鸡生产性能、饲粮养分代谢率和粪中微量元素含量的影响。1组为对照组饲喂基础饲粮,其Fe、Cu、Mn、Zn分别由硫酸亚铁、硫酸铜、硫酸锰和氧化锌提供,添加水平分别为Fe 100 mg/kg、Cu 20 mg/kg、Mn 120 mg/kg和Zn 120 mg/kg;2、3、4和5组分别用12.5%、25.0%、37.5%和50.0%的蛋氨酸螯合铁、铜、锰、锌替代基础饲粮各相应无机微量元素的25%、50%、75%和100%。63 d的试验结果表明:与对照组比较,用不同水平蛋氨酸螯合物(铁、铜、锌、锰)替代相应无机盐可一定程度提高肉鸡的生产性能,改善饲粮养分利用率,提高养殖效益,降低粪中微量元素的排泄量,尤以37.5%的蛋氨酸微量元素螯合物替代饲粮中75%的相应无机微量元素的效果良好。