新型天然海藻钙源

<正> 有关专家指出,骨质疏松症已成为全球所关注的疾病之一。钙缺乏被认为是骨质疏松症及其相关疾病的主要原因。据新的膳食参考摄入量(DRIs)推荐,存在罹患骨质疏松症高危的成人每日应摄入1,000～1,300毫克钙(美国医药研究所)。就全球而言,人均膳食钙的摄入量并不足够。因此,增加人们钙摄入量的最佳途径是对食品和饮料     

牦牛骨粉对大鼠骨钙、骨密度及骨钙吸收率影响的研究

目的:研究牦牛骨粉钙吸收率及对大鼠骨钙、骨密度的影响。方法:清洁级雌性SD大鼠,70只,随机分为7组,即低钙对照组(饲料中含钙量为1180mg/kg),牦牛骨粉高、中、低三个剂量组(相当于人体推荐摄入量的5、10、20倍),实测值饲料中含钙量为1437、1852、2778mg/kg,另设与样品对照组剂量相对应的三个碳酸钙对照组。于实验第4w末进行三天的钙代谢试验。整个喂养时间为12w,实验结束日,测右侧股骨长度,干重,骨钙含量及骨密度。结果:牦牛骨粉10、20倍剂量组股骨钙含量、股骨骨密度高于低钙对照组,5、20倍剂量组钙表观吸收率高于相应剂量的碳酸钙对照组(p<0.05)。结论:牦牛骨粉不仅有增加骨密度功能,并具有较高的钙表观吸收率。     

钙源的比较与应用

<正> 现在人人都认识到钙是一种重要的矿物质,对儿童和年老妇女尤其重要。儿童从婴儿时骨骼便不断生长,当人进入老年期,骨中钙的流失速度超过新骨的生长,在这阶段钙源的补充尤显重要。据报道,美国的冷冻桔子汁饮料市场中,钙强化饮料的增长迅猛。目前钙强化果汁饮料已占果汁饮料市场的15％,其市场份额增长达32％,而普通果汁饮料仅有3％的增长。 溶解性 乳酸钙是最为有效的钙源,它是L(+)乳酸的天然矿物盐。在果汁饮料(尤其是澄清果汁),运动员饮料和多种矿物质饮料中加入钙,最重要的是不     

钙营养缺乏及合理补钙

钙是人体必需的矿物元素,适量的钙供给对人体健康至关重要,缺钙会引起儿童佝偻病、中老年骨质疏松、骨软化等疾病。我国居民膳食中钙摄入严重不足,仅占供给量标准的５０％左右。据１９９２年全国营养调查的结果表明,钙是中国居民膳食中缺乏最明显的营养素。近年来,随着人们对钙摄入量与儿童、青少年骨质发育和成人骨健康关系认识的不断深入,对补钙食品和钙制剂的需求日益增加,补钙成为人们关注的热点。 一、钙的主要生物学功能 钙是人体中含量最多的无机元素,约占体重的ｌ．５０～２．００。人体总钙含量达１３００ｇ,其中９９％以…     

影响微生物富钙因素的研究

用微生物富集钙,氯化钙是一种较好的钙源,其钙浓度以Ca2 计为0.6%时,有利于富钙微生物菌丝体的生长及对钙的富集;食用丝状真菌F2生物量大、富钙率高,且含有较高的蛋白质、维生素和各类氨基酸,是一种较理想的富钙菌种;生物钙制剂含有易被人体吸收的氨基酸钙,可作为目前钙制剂的换代产品。     

钙的食品强化

钙是人体骨骼生长和调节生理功能的重要物质,但缺钙现象非常普遍,为满足人们补充钙质的需要,各式各样的补钙产品和强化钙的食品也越来越多。本文简述了钙对人体的作用,并对开发强化钙食品的钙源选择和钙的食品强化进行了概述。     

国人钙摄入不足推荐量一半

正近日,从事骨质疏松研究的非营利组织——国际骨质疏松症基金会公布了1项针对近57万人所做的"中国骨健康常识"调查。报告显示,有53.50%的受访者有膳食平衡的基本观念,注意肉、菜、奶搭配;44.63%的受访者知道牛奶是有效的补钙手段。但《中国居民膳食指南》(2011版)也指出,中国居民膳食不合理现象仍然存在,特别是钙摄取严重不足。我国城乡居民膳食钙摄入量平均为389毫克,不及推荐量     

透明质酸钙毒理学研究

目的研究透明质酸钙的毒理学特性。方法分别进行小鼠急性毒性实验和大鼠30 d喂养实验。结果样品对小鼠的急性毒性LD50大于5 g/kg;实验期内大鼠生长发育良好,血常规及血生化各项指标均在正常范围,病理组织学检查各脏器均未见有意义的病理改变。结论根据人体最大可能摄入量(100 mg/d)和急性毒性分级标准,透明质酸钙为无毒物质,对人体无毒害及副作用。     

透明质酸钙毒理学研究

目的 研究透明质酸钙的毒理学特性.方法 分别进行小鼠急性毒性实验和大鼠30 d喂养实验.结果 样品对小鼠的急性毒性LD50大于5 g/kg;实验期内大鼠生长发育良好,血常规及血生化各项指标均在正常范围,病理组织学检查各脏器均未见有意义的病理改变.结论 根据人体最大可能摄入量(100 mg/d)和急性毒性分级标准,透明质酸钙为无毒物质,对人体无毒害及副作用.     

人体罐钙与钙营养强化剂的选用

钙是人体骨骼 和牙齿的主要成分，并可参与人体的多种生理活动。我国缺钙现象相当严重，单靠食物摄钙，仅能达到中国营养学会推荐标准的４９．２％。目前我国规定的钙营养强化剂约１８种，其中国家规定１４种，新审批４种。选择钙营养强化剂时应注意钙含量、溶解度，吸收率，安全性，口感、价格等因素，介绍了一种瓣型钙营养强化剂：Ｌ－乳酸钙。     

Eggshell powder,a comparable or better source of calcium than purified calcium carbonate: piglet studies

Powdered chicken eggshells might be an interesting and widely available source of calcium. In two studies using piglets we determined the digestibility of calcium from different diets. The first study compared casein-based diets with CaCO₃ (CasCC) or eggshell powder (CasES). The second study compared soya protein isolate-based diets with CaCO₃ (SoyCC) or eggshell powder (SoyES). Diets were fed to groups of six piglets. Faeces were collected quantitatively. No adverse effects of eggshell powder were observed with regard to magnesium and crude fat digestibility. Calcium from eggshell powder was more digestible than calcium from purified CaCO₃. In the first study, digestibility coefficients for calcium were 66.9 (SD 7.9)% for CasCC and 71.3 (SD 3.8)% for CasES. In the second study, these coefficients were 46.7 (SD 8.6)% for SoyCC, and 65.9 (SD 3.7)% for SoyES, a significant difference. Our conclusion is that eggshell powder is, in the case of casein-based diets, as good a source of calcium as CaCO₃ and, in the case of soya protein-based diets, better than CaCO₃ for growing piglets. As the piglet model is considered to be representative for humans, chicken eggshell powder is also a promising source of calcium for human nutrition. © 1999 Society of Chemical Industry     

蛋白钙的研究

主要介绍通过新工艺从虾头中提取蛋白钙的工艺方法,并对该产品进行动物及临床验证,结果表明该产品人体易吸收,是一种较好的钙补充剂.     

Effects of legume processing on calcium,iron and zinc contents and dialysabilities

Legumes are a good source of calcium, iron and zinc, but are also a source of phytates and dietary fibre components that can negatively affect the bioavailability of these minerals. To estimate the latter, an in vitro dialysis method can be applied that gives the dialysability of a mineral as an estimate of its availability for absorption. Calcium, iron and zinc contents and dialysabilities in three legumes (beans, chickpeas and lentils) and the effects of cooking treatments and industrial processing on these parameters were studied. Beans had the highest calcium content (1.54 g kg^?1 dry matter (DM)) and chickpeas the lowest iron content (46.9 mg kg^?1 DM), whilst the zinc contents were similar in all three raw legumes (33.7–36.9 mg kg^?1 DM). Traditional and microwave cooking reduced the mineral contents by 9.7–36.4% for calcium, 14.2–31% for iron and 11.1–28.9% for zinc. The dialysabilities of calcium with respect to the values for the raw products were also reduced by these cooking techniques. Industrially processed legumes had higher dialysabilities of calcium, iron and zinc than traditionally or microwave cooked legumes. © 2001 Society of Chemical Industry     

Analysis of calcium in milk using an embedded system

The objective of the present work is to design and implement a low cost PIC18F452 microcontroller based instrument for the measurement of calcium in milk samples using Light Emitting Diode (LED) as source and photodiode as detector. The developed instrument measures the absorbance, calculates the concentration and displays the results in Liquid Crystal Display (LCD). The principle of the measurement is based on the reaction between calcium and Ortho Cresolphthalein Complexone (OCPC) reagent in alkaline medium to form purple complex with maximum absorption at 570 nm. Algorithm is developed to monitor and control the process sequences and transmit data to PC via serial communication module using an RS232 protocol. Statistical analyses are carried out to evaluate the performance characteristics of the developed instrument and compared with the conventional instrument. Linear calibration curve is obtained between 0 and 5.0 mmol L^?1 and lower limit of detection is 0.05 mmol L^?1. The developed system shows the good performance and the results are in good agreement with the current clinical spectrophotometric method at 96% of confidence level.     

胶原多肽螯合钙的研究进展

目前我国居民钙摄入量不足,普遍存在缺钙现象,传统的补钙制剂存在缺陷,将逐步被新型钙制剂所取代。胶原多肽螯合钙作为新型生物钙制剂,具有吸收效率高、无副作用、服用方便等特点,是一种良好的补钙产品。近些年来,许多学者研究胶原多肽螯合钙,为补钙产品提供了新思路。胶原多肽作为其原料的一部分,与钙螯合后可以帮助钙的转运和吸收,被一起摄入后兼补了两种营养素。从一些动物加工的副产物中可以提取胶原多肽和钙,利用他们为原料制备胶原多肽螯合钙有利于副产物的高值化,也为副产物的利用提供了新途径。本文主要对胶原多肽螯合钙的原料制备、螯合工艺、螯合效果的影响因素、发展前景进行了概述。     

Problems in fractionating calcium in plant tissue

Established procedures for the fractionation of calcium in plant tissue have been investigated. Because of the varying solubilities and the imprecise nature of many forms of calcium, such as pectate and phytate, most fractions resulting from successive solvent extraction have little meaning. A modified procedure involving extraction in acetic acid and HCl is shown to give a good measure of that calcium associated with oxalate.     

膳食中钙磷比例风险评估的研究

通过对五大类食品中的钙磷含量进行测定,进行钙磷比例风险评估并提出合理化建议。结果表明,奶制品、豆制品、肉骨头是人体补钙的最良好天然来源,建议缺钙的人每天正餐和饭补充一粒钙含量达到300mg的高钙片,可有效解决当前食品中钙缺乏、钙磷比不合理的现实问题。     

Traditional materials from new sources – conflicts in analytical methods for calcium carbonate

Calcium carbonate (E170) is a common food and pharmaceutical additive/ingredient. In addition to a source of calcium, the carbonate has uses including as a colour, acidity regulator and bulking agent. Globally, a range of regulatory agencies and pharmacopoeia control the analyses and specification of additives in food, supplements, pharmaceutical substances and excipients. Accordingly, a range of specifications and analyses exist for calcium carbonate depending on the application and market of the product. In this contribution, we analyse calcium carbonates from geological, synthetic and biogenic sources, focussing on acid insoluble impurities, a test required by current monographs. Analysis of calcium carbonate from different origins may require modification of existing tests to comply with regulatory bodies, due to the variation of impurities specific to the source of the material. We suggest an analytical approach involving centrifugation that improves analytical efficiency (up to 85% time reduction), especially for calcium carbonate of biological origin.     

In vitro calcium availability from brassica vegetables (Brassica oleracea L.) and as consumed in composite dishes

In vitro calcium availability from four varieties of Brassica oleracea L. (broccoli, cauliflower, green cabbage and kale) was evaluated. The effect of including some brassica vegetables in composite dishes (macaroni and broccoli, macaroni and cauliflower) was also studied. Brassica vegetables were rich in calcium (20.6–35.3 mg/100 g) and in organic acids. Dietary fibre content in brassica vegetables (2.4 g/100 g) was lower than in composite dishes, the latter having a higher content of the soluble fraction. Uronic acids represented 50% of the soluble fibre fraction of brassica vegetables and only 24% of that of composite dishes. Approximately 25% of the total calcium of brassica vegetables was dialysable; ionic dialysable calcium was about 7% of the total calcium. The addition of macaroni to vegetables significantly lowered only calcium dialysability (p<0.001). Unlike vegetables, composite dishes had a percentage of soluble calcium higher (p<0.001) than that of dialysable calcium. The presence in dialysates of higher amounts of bound calcium compared to free ionic calcium implies that most of the absorbable calcium was bound to low molecular weight compounds. Organic acids might constitute the main association of calcium in brassica vegetables. Brassicaceae can be regarded as a good source of available calcium; their consumption in the diet may contribute to an adequate calcium nutriture.     

乳酸菌富集钙的研制

利用人体肠道有益菌——乳酸菌发酵不同粒度的超微粉碎贻贝壳粉,通过研究发酵过程中超微粉碎贻贝壳粉中结合钙游离的影响,优选出乳酸菌发酵贻贝壳粉的最佳生产工艺。结果表明,当贻贝壳粉粒度为1000目、接种贻贝壳粉浓度为20%、乳酸菌接种量为3%、蔗糖浓度为5%时,贻贝壳粉结合钙最大游离转化率为29.6%,从而开发出一种新型的生物态补钙制剂。