锌代谢池—判断人体锌营养状况的可靠指标

用稳定性同位素锌(~(68)Zn和~(70)Zn)对2例志愿者进行了历时15周不同锌营养水平的代谢实验。结果表明,锌代谢池能正确地反映人体的锌营养状况。空腹和餐后血浆锌浓度的差别比单独测定空腹血浆锌浓度更为可靠。每日尿锌和粪锌的排泄量则有一定的局限性。粪便中内源性锌排泄量的测定对确定人体每日锌的供给量标准,具有一定的参考价值。     

锌代谢池—判断人体锌营养状况的可靠指标

用稳定性同位素锌(~(68)Zn和~(70)Zn)对2例志愿者进行了历时15周不同锌营养水平的代谢实验。结果表明,锌代谢池能正确地反映人体的锌营养状况。空腹和餐后血浆锌浓度的差别比单独测定空腹血浆锌浓度更为可靠。每日尿锌和粪锌的排泄量则有一定的局限性。粪便中内源性锌排泄量的测定对确定人体每日锌的供给量标准,具有一定的参考价值。     

人体微量元素研究的进展(一) 锌

本文综述与人体有关的三种重要的微量元素锌、锰和铜研究的进展,特别着重体内代谢及失调方面的生理、生化和病理变化。一、锌1.吸收:一个70公斤的人体含1.4～2.3克锌。成人大约每天摄入10～15毫克锌,由小肠吸收5毫克左右。锌在小肠的吸收不是简单的扩散,而是受某种机理调节的。胃肠外给小鼠过量的~(65)Zn,可使大便中~(65)Zn排泄加速,而口服不行。在身体锌负荷增加时~(65)Zn的吸收减少。Evans等指出,锌吸收的变化与肠粘膜锌含量有关,后者又受血浆锌含量的调节。     

谷豆型混合膳防治儿童缺铁性贫血效应的实验观察

利用大豆发酵降解植酸技术,生产出系列儿童营养主食品,提高了植物性食品中铁的吸收利用率。经437名幼儿食用半学年后,缺铁性贫血率由21.7％下降至1.07％,经用稳定性同位素~(58)Fe中子活化法测得大豆发酵食品组膳食铁吸收率(21.8％)比对照组铁吸收率(14.3％)显著增高(P<0.01),与加食硫酸亚铁组(22.4％)比,效果相同(P>0.05)。     

云南五个民族儿童血铅及血清锌、铜、钙水平现状调查

【目的】了解云南省同一地域不同民族儿童血铅(Pb)及血清锌(Zn)、铜(Cu)、钙(Ca)元素水平现状。【方法】对云南省某哈尼族、傣族自治县五个不同民族(汉族、白族、傣族、彝族、哈尼族)3~7岁健康儿童共751名,应用美国PE-300型原子吸收光谱仪、日立7060生化分析仪测定儿童全血Pb及血清Zn、Cu、Ca含量,对各民族间元素水平进行比较,并对各民族儿童生活环境及习俗等问卷调查情况进行分析。【结果】汉族、白族、傣族、彝族、哈尼族儿童血Pb及血清Cu、Ca水平均值分别为66~67μg/L、1.21~1.28 mg/L2、.40~2.48 mmol/L,三种元素含量呈现较为集中趋势,五个民族三种元素比较差异无显著性(P>0.05);血清Zn均值分别为0.77、0.72、0.85、0.85、0.84 mg/L,白族血清Zn含量低于其它民族儿童(P<0.05)。751例民族儿童中儿童铅中毒率13.8%,低于昆明市城区儿童(24.9%)。五个民族儿童Zn、Cu、Ca总缺乏率分别为16.1%、3.5%、13.0%,各民族儿童间元素缺乏状况不同,白族儿童Zn、Ca微/宏量缺乏率(27.1%、18.7%)高于其它民族儿童、傣族儿童Zn、Ca缺乏率(9.1%、8.0%)最低,本次调查对象中未检出Zn、Cu、Ca过量儿童。【结论】同一地域不同民族儿童微/宏量元素水平存在差异。     

锌营养水平诊断指标的动物实验研究

将40只断乳的WKA系雄性健康大鼠,随机分成5组,其中3组分别畏以含锌6、15和24ppm的合成饲料8周,不锈钢单笼饲养。结果表明6ppm组大鼠体重增长缓慢,摄食量下降,蛋白质功效比值、蛋白质净比值及食物效能也均显著降低(P<0.05)。除了这些低锌的一般反应外,值得特别注意的是大鼠的毛锌浓度、碱性磷酸酶活性(AKP)、胫骨锌和肾锌浓度及含量,肝、肾、脑、睾丸及胫骨中的锌含量及其~(65)Zn的比值、粪、尿~(65)Zn排出率都显著(P<0.05)或极显著(P<0.01)地低于15ppm组和24ppm组。我们认为这些指标较敏感地反映了大鼠锌营养状况。对锌营养不良有重要诊断意义。另外,6ppm组大鼠全血超氧化物歧化酶(SOD)试验后期也显著降低,有一定诊断意义。     

富锌豆制品的开发实验

在普通的豆制品生产工艺中添加含锌食品凝固剂 ,研制出富锌豆制品 ,作为强化锌食品。富锌豆制品感官鉴定呈白色或黄色 ,具有弹性 ,味细嫩 ,无异味。1　方法1.1　含锌食品凝固剂配制称取 87.5 3mg氯化锌 ,放入一定比例的卤水中 ,待充分溶解后备用 ,其 Zn Cl2 浓度为 87.5 3m g/ kg大豆。筛选过的大豆用自来水洗净并浸泡 2 4h,粉碎、过滤、压榨、去渣后煮沸 ,用含锌的食品凝固剂均匀的点在煮沸的大豆浆中(点脑 ) ,经养脑、压榨、翻版、空水后制成成品。1.2　富锌豆制品含锌量侧定用原子吸收分光光度仪测定富集在豆制品中的含锌量 ,同时设同一…     

发芽大豆蛋白提高锌生物利用率的研究

本文采用放射性同位素~(65)Zn示踪法,将大豆进行发芽处理,降低其中对锌的抗营养因素,提高促进锌生物利用因素以后,通过实验比较发芽大豆粉,未经处理的大豆粉以及公认的优质蛋白质来源的蛋清蛋白粉对大鼠膳食中锌的生物利用率、锌的分布、锌的吸收、锌的排泄、锌的平衡以及锌的潴留等方面的影响的研究,明确了发芽大豆粉对锌生物利用率的作用。为我国充分开发与合理利用大豆这一植物蛋白质资源,从锌生物利用率上再次提供重要的理论依据和确切的实验数据。     

胃癌患者的血清锌值

<正> [氏家重纪、他:癌の临床31(11):1372～1376,1985(日文)]患癌动物的血清锌(Zn)值降低,一般认为有以下三个原因:其一,因为血清中的 Zn 大约70%要与白蛋白结合,所以可认为血清 Zn 的降低是继发于血清中白蛋白的减少(癌症后期产生恶液质,引起血清白蛋白减少);其二,患癌机体的肝脏中锌含量增加,因此血清Zn 值降低是 Zn 由血清向肝脏转移增加的缘故;其三,因为许多恶性肿瘤组织中含有大量     

~(65)Zn在锌的生物利用率研究中的应用

用~(65)Zn同位素示踪法研究体锌缺乏及正常小鼠体内锌的生物利用率结果表明:体锌缺乏时对锌的吸收率(71.9±3.6％)显著高于体锌正常(38.8±6.8％,P<0.01)时;体内锌的分布与锌的营养状态无关;肝脏、脾脏、肾脏和肌肉中~(65)Zn比活度,体锌缺乏显著高于体锌正常,锌在体内廓清呈二项指数函数,血液、脾脏、肾脏、肺脏、骨骼及肌肉中~(65)Zn的廓清速率,体锌缺乏显著慢于体锌正常,分配到体锌缺乏组的慢廓清相的份额显著大于体锌正常组。     

艾滋病病毒感染者/病人“种豆吃豆”项目效果评价

目的了解安徽省艾滋病病毒感染者/病人"种豆吃豆"试点活动开展情况,全面评估活动实施效果,为在项目地区进一步推广提供依据。方法采取普查方法,对2个县(区)参与项目所有可接触到的47名艾滋病病毒感染者/病人进行问卷调查,并入户核实调查结果。结果在47名调查对象中,共接受豆种320.5kg,收获大豆3 465kg,较投入增加了9.8倍,87.2%对象接受过培训,97.9%的人均食用了大豆,平均每人每周吃豆6.4±2.6次,喝豆浆者占89.4%,89.1%的对象自报吃豆后感觉身体较以前好,86.7%自报比吃豆前生病少,总蛋白、白蛋白和血红蛋白较吃豆前增加者分别占61.11%、61.11%和57.89%,且前两者在吃豆前后比较均有显著性差异(t=3.8136,P<0.05,t=2.6697,P<0.05),CD4较吃豆前增加的占54.05%;97.9%人认为此项目好,所有人都希望继续开展该项目。结论该项目改善了感染者/病人的营养状况和知识水平,减少了机会性感染的发生,"种豆吃豆"试点活动效果明显,并具有可持续性。     

Zinc deficiency increases the osmotic fragility of rat erythrocytes

Zinc deficiency in rats causes increased osmotic fragility of their erythrocytes. This study was designed to determine the relationship of food intake and dietary sulfur amino acid level to the effect of low zinc status on fragility. Immature rats were fed for a 3-wk period a low zinc diet (less than 1 mg/kg) based on isolated soybean protein or a similar control diet (100 mg Zn/kg diet) supplied either ad libitum or by pair feeding. Fragility was measured by the degree of hemolysis in hypotonic saline solutions. In the first experiment, zinc deficiency resulted in higher fragility than in ad libitum controls; pair-fed controls were intermediate and not different from either. Experiment 2 included two levels of methionine, 0.4 and 0.9%, and two of zinc, 0 and 100 mg Zn/kg diet. At the 0.4%, but not at the 0.9% methionine level, hemolysis of red blood cells from the zinc-deficient rats was significantly greater than those from either pair-fed or ad libitum controls. Repletion for 1 or 2 d completely alleviated the increased fragility, but in vitro addition of zinc had no effect. Restricted intake of the zinc-adequate diet reversed the fragility within 1 d as readily as did ad libitum intake. Thus, the osmotic fragility induced by zinc deficiency was prevented by high sulfur amino acid intake and was readily reversed by dietary zinc. It is postulated that extracellular or membrane-bound zinc protects a component of the membrane that is essential to its function, and that reversal of the defect requires an in vivo metabolic process.     

高效液相色谱定量分析发酵豆制品中大豆异黄酮和Monacolin K

目的建立高效液相色谱定量分析发酵豆制品中大豆异黄酮和Monacolin K的方法。方法采用polaris C1(82.0mm×100mm,3μm),水(含0.3%H3PO4)、乙腈为流动相,梯度洗脱,流速:0.3ml/min,柱温50℃,测定波长(λ):大豆异黄酮260nm;Monacolin K为237nm。分析了发酵豆制品中大豆异黄酮和Monacolin K。结果在选定色谱条件下大豆异黄酮和Monacolin K其线性范围在0.2～45mg/L,样品加标回收率88.9%～101.1%,相对标准偏差为0.89%～3.19%.结论本方法精密度好,结果可靠.适合于发酵豆制品中大豆异黄酮和Monacolin K的定量分析。     

Nutritional and sensory evaluation of tempe-fortified maize-based weaning foods

Maize-based weaning foods prepared from whole maize meal or dehydrated fermented maize (ogi) flour fortified with soybean, cowpea or groundbean tempe, with or without the addition of melon seed flour were fed to 40 albino weanling rats. The nutrient quality of the weaning foods was monitored by the measurement of protein efficiency ratio (PER), net protein ratio (NPR), true digestibility (TD), biological value (BV) and net protein utilization (NPU). Amino acid composition and amino acid scores were determined. The weaning foods were also evaluated for sensory properties and acceptability by nursing mothers and their children. Protein efficiency ratio, net protein retention and net protein utilization of the fortified weaning foods were not significantly different (P > 0.05) when compared to casein diet (control). True digestibility of tempe-fortified maize-based weaning foods averaged 85.4 +/- 3.4% compared to 94.4%, for casein diet. Results from sensory analysis showed that relative to tempe-fortified maize-based weaning foods, most mothers preferred Cerelac, a commercial weaning food, and its porridge because of its vanillic flavour and sweet taste. Despite the low scores recorded for aroma and taste of tempe-fortified maize-based weaning foods, most mothers and their children found porridges prepared from these foods acceptable, with a preference for ogi fortified with cowpea tempe. Tempe-fortified maize-based weaning foods had high protein quality and can support the growth of infants in developing countries especially during the critical weaning period (6-12 months). They were comparable to Cerelac, a commercial baby food in colour and texture.     

Zinc and copper: proposed fortification levels and recommended zinc compounds

Micronutrient fortification of foods is now a highly relevant tool worldwide for overcoming micronutrient deficiency. Recent data show that subclinical zinc deficiency is widespread; in Mexico a national survey showed that 25% of children less than age 11 y had plasma zinc concentrations below 10.0 micromol/L (65 microg/dL). Copper deficiency in populations is unknown but copper supplementation is recommended to accompany zinc supplementation. Of the foods available for fortification, staple cereals are very good candidates for reducing micronutrient deficiencies. Because of its higher stability and lower cost, we recommend fortification of cereal flours with zinc oxide, which is absorbed as well as the less stable and more expensive forms of zinc. Depending on the amount of the food that is expected to be eaten, zinc fortification of staple foods could be 20-50 mg/kg of flour. For copper fortification the safer compound is copper gluconate. Copper sulfate is significantly less expensive, but an evaluation of potential physicochemical reactions that affect the final food product is recommended. The suggested amount of copper added to staple foods is 1.2-3.0 mg/kg of flour. For food supplements designed as part of supplementation programs to reduce micronutrient deficiency in children less than age 3 y, a dose of the final product (usually approximately 40-50 g) should contain approximately 4-5 mg of zinc and approximately 0.2-0.4 mg of copper depending on the habitual diet, magnitude of deficiencies and period of supplementation.     

豆类发酵食品中维生素B_(12)的分离与定量

植物性食物不含维生素B_(12),但我们曾发现发酵食品中可检出维生素B_(12)活性物质。为了进一步确定这类食品中具有生理作用的钴维生素含量,建立了维生素B_(12)生物自显谱面积定量法,其要点如次:豆类发酵食品提取液点于滤纸上,以仲丁醇—水—氢氧化铵—5％氰化钾(100:50:1:0.25)为扩展剂,下行扩展,24—72小时后取出干燥,然后置于含有E、Coli44110及2,3,5—三苯基四唑(鎓)化氯的营养琼脂培养基上,显谱后测量生长圈面积,计算样品中钴维生素含量。 用上述方法测定了两种豆类发酵食品,其钴维生素含量均值:每百克臭豆付乳中含0.97μg,酱豆付乳含0.4μg。与动物性食品相比,这两种豆类发酵食品可视为维生素B_(12)较好来源。     

Fermentation of soybean flour with Aspergillus usamii improves availabilities of zinc and iron in rats

Soybean flour was fermented with Aspergillus usamii to improve the availabilities of dietary zinc and iron through the degradation of phytate. Three kinds of experimental diets that differed in protein sources were prepared: one consisting of 40% fermented soybean flour (RS diet), one consisting of 40% fermented soybean flour (FS diet), and one consisting of 20% regular soybean flour and 20% fermented soybean flour (RF diet). Zinc solubilities in the upper and the lower segments of the small intestine were higher in rats fed the FS diet than in rats fed the RS diet. The FS group showed higher solubility of iron in the lower small intestine than the RS group did. Zinc concentrations in the femur and plasma and iron concentrations in the liver and plasma were higher in the FS group than in the RS group. These results suggested that the fermentation of soybean flour improved the availabilities of dietary zinc and iron, which may be induced by increasing the solubilities of these minerals in the small intestine through the reduction of phytate content. Femoral and plasma zinc concentrations in the RF group were higher than in the RS group, but lower than in the FS group. No difference was noted in liver and plasma iron concentrations between the RF group and the FS group. Although phytase activity in FS degrades phytate in the RF diet, higher activity may be needed to degrade phytate completely.     

烟台市发酵性调料中氨基甲酸乙酯污染状况调查

目的:探讨烟台市发酵调料中氨基甲酸乙酯(ethyl carbamate,EC)污染状况,对本地区发酵性调料的食品安全性进行调查与评估。方法:随机选取2011年烟台市超市及食品供销部的158份发酵食品,应用基质固相分散萃取(MSPD)技术GC/MS定量分析各类发酵调料食品中EC的含量。结果:(1)158份发酵性调料食品中阳性样品数为117份,阳性率为74.05%,其中黄酒及料酒中EC阳性率最高,平均含量分别为73.1μg/kg、66.4μg/kg,酱油和食醋中EC的含量相对较低,平均含量为40.3μg/kg、29.1μg/kg,腐乳EC平均含量为27.5μg/kg;(2)EC阳性腐乳样品数为36份,其中红腐乳19份,白腐乳17份,两组间EC含量水平无显著差异性。结论:烟台市发酵调料食品中普遍存在EC,其中黄酒及料酒中EC阳性率最高,且EC含量最高值为100.2 mg/L,发酵调料的食品安全问题应进一步加强监管、严格调控。     

The anti-inflammatory action of fermented soybean products in kidney of high-fat-fed rats

Soybean has many compounds with a variety of biological properties that potentially benefit human health; among them, isoflavones have inhibitory effects on lipid oxidation in adipose tissue. In this study, we examined two Korean traditional fermented soybean products--doenjang (DNJ) and cheonggukjang (CGJ)--for their ability to suppress redox-sensitive nuclear factor κB (NF-κB) activation in the kidney of rats fed a high-fat diet. Sprague-Dawley rats, 4 weeks old, were fed soybean, DNJ, or CGJ (1?g/kg/day) with a 20% fat diet for 6 weeks. Body weight and food intake were carefully monitored. NF-κB-related activities of genes for inflammatory proteins, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and vascular cell adhesion molecule-1 (VCAM-1), were determined. The soybean products exhibited antioxidative action by maintaining redox regulation, suppressing NF-κB activation, and modulating the expression of genes for NF-κB-induced inflammatory proteins such as COX-2, iNOS, and VCAM-1. Based on these results, we conclude that Korean traditional soybean fermented products, especially CGJ, suppress the generation of reactive species, NF-κB activity, and NF-κB-related inflammatory genes.     

A potential synbiotic product improves the lipid profile of diabetic rats

ABSTRACT: BACKGROUND: Previous studies showed that intake of yacon or some lactic acid bacteria was able to inhibit the development of diabetes mellitus, by reducing glucose and associated symptoms, for example, the lipid profile. OBJECTIVE: The purpose of this study was to assess the consumption influence of a potential symbiotic product of soybean and yacon extract and fermented Enterococcus faecium CRL 183 and Lactobacillus helveticus ssp jugurti 416 in reducing blood glucose and lipid levels in an animal model. METHODS: Diabetes mellitus was chemically induced by intraperitoneal administration of streptozotocin (50 mg/kg body weight). The rats were divided into four groups (n=10): GI -- non-diabetic animals that received only a standard chow diet (negative control), GII -- diabetic animals that received only chow diet (positive control), GIII -- diabetic animals that received the chow diet + 1 mL/kg body weight/day of soybean and yacon unfermented product, GIV -- diabetic rats that received the chow diet + 1 mL/kg body weight/day of soybean and yacon fermented product. There was a seven-week treatment period and the following parameters were evaluated: animal body weight, food and water intake, blood glucose, enzyme activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT), triglycerides levels, total cholesterol, HDL-C, non-HDL-C. Cell viability of the fermented product was checked weekly for a seven-week period. RESULTS: The product average viable population was 108-109 CFU/mL, by ensuring both the rods and cocci regular intake. No difference was observed between the water and feed intake and body weight of groups that received unfermented and fermented products and the untreated diabetic group. The same was observed for the blood glucose and AST and ALT activities, while some improvement was observed for a lipid profile, represented by reduction of triglycerides level by 15.07% and 33.50% in groups III and IV, respectively, and an increase of 23.70% in HDL-C level for group IV. CONCLUSION: The results showed that the ingestion of a potential symbiotic product was neither able to promote improvement in some of the disease symptoms, nor reduce blood glucose. However, a positive effect on triglycerides levels and HDL-cholesterol was observed in the groups that received the unfermented product containing yacon extract and the fermented product with Enterococcus faecium CRL 183, as well as Lactobacillus helveticus ssp jugurti 416 and yacon extract (symbiotic product).