三带喙库蚊幼虫饲料的研究

三带喙库蚊是流行性乙型脑炎主要传播媒介。为研究和掌握它的生态习性、繁殖规律、进而为实验室筛选有效杀虫剂、国内外都在室内通过人工饲养建立三带喙库蚊实验室种群。在人工饲养中幼虫饲料是蚊幼虫的生长发育及繁殖传代的关键。我国饲养7种常见蚊幼虫饲料为炒面粉、酵母粉或肝粉。其中三带喙库蚊幼虫饲料为羊肝粉和馒头粉。我们于1983年首次选用以鱼松、动物肝粉等原料先后研制了多种类型的三带喙库蚊幼虫饲料配方,对28种配方和4种主要原料分别进行了人工饲养效果比较,并分析了饲料配方组成的营养成份含量及不同饲料对幼虫存活率、生长发育、化蛹距羽化时间、雌、雄性比例、繁殖周期等系列观察、选出了6种适合三带喙库蚊幼虫生长发育的饲料配方。连续饲     

几种铁营养资源的生物利用率评价

兔肝粉、禽肝粉、猪肝粉、鱼肝粉、酵母粉五种铁营养资源都含有丰富的铁、蛋白质等营养成份。以大鼠为生物模型,用预防性评价法(Prophylactic Assay)对五种铁资源中铁生物利用率进行了测定。结果表明:五种铁资源中铁吸收利用良好,生物利用率较高。兔、禽、鱼、猪等肝粉与酵母粉中铁的相对生物价(RBV)分别为:88.5％,85.5％,85.0％,48.0％,132.5％。这些资源可以作为防治婴幼儿缺铁性贫血的补充铁源。大鼠模型对评价铁的生物利用率具有简便、实用、需时短、结果明确的优点。     

3种物质不同配比对美洲大蠊若虫生长的影响

目的筛选美洲大蠊若虫饲料的优化配方。方法采用L（934）设计方法,研究小麦粉、奶粉、干酵母粉3种物质不同配比对美洲大蠊若虫生长发育的影响。结果实验结果表明,若虫饲养120d后,取食配方S5的若虫体长增量（19.21mm/只）、日取食量（25.94mg/只）、体重（532.5mg/只）及若虫对饲料的利用率（96.69%）均高于取食其他配方饲料的若虫。结论美洲大蠊若虫最佳的饲料配方为小麦粉：奶粉：干酵母粉=2：4：1。干酵母粉是美洲大蠊若虫体长增量的关键因子,有利于若虫的生长。     

膳食n-6/n-3脂肪酸比值对小鼠淋巴细胞脂肪酸构成和功能的影响

目的观察膳食n6n3脂肪酸比值对淋巴细胞脂肪酸构成及细胞功能的影响。方法BALBc小鼠随机分为5组n6n3比值分别为1(A组)、75(B组)、15(C组)、30(D组)和正常对照组,其中实验组S∶M∶P模拟中国居民膳食脂肪酸摄入的S∶M∶P为1∶15∶1,正常对照组为AIN93G配方的1∶15∶37。基础饲料采用AIN93G配方,脂肪酸构成以食用油脂调配。饲养12周。测定小鼠T淋巴细胞功能,脾淋巴细胞脂肪酸构成、PGE2水平。结果n6n3比值接近1时,小鼠T淋巴细胞增殖活性、CD4+、CD8+T细胞比例、培养上清IL2、PGE2水平显著降低;淋巴细胞C18∶2、C20∶4、n6PUFA含量显著减少;C22∶6、C16∶1、C18∶1、总MUFA含量明显高于其他实验组。淋巴细胞C22∶6含量与淋巴细胞增殖活性显著负相关;C20∶5含量与CD4+T淋巴细胞比例、IL2水平显著负相关;C16∶1含量与CD4+、CD8+T淋巴细胞比例显著负相关。结论小鼠脾淋巴细胞的脂肪酸构成受膳食脂肪酸构成的影响;n6n3比值为1组与比值为30的膳食组相比较,小鼠T淋巴细胞增殖活性受到抑制。     

德国小蠊规格化养殖的研究

德国小蠊是一种分布广、危害严重的室内卫生害虫。为了给有关实验研究提供规格化的试虫,作者等进行了规格化养殖的研究。结果表明,德国小蠊最适宜的饲养条件是:环境温度28°±0.5℃;饲料为豚鼠料粉17份,酵母粉1份,肝粉1份,糖1份混合制成的料块;饲养密度按容器的底面积计算,1只/cm~2。按上述条件饲养的虫体发育快、存活率高、繁殖量大,从而使养殖工作不但节省人力、物力和空间,且达到科学化、规格化、计划化。     

淄博市部分学校食堂面粉中过氧化苯甲酰检测情况

过氧化苯甲酰 (benzoylperoxide)是一种弱氧化剂 ,作为面粉改良剂对面粉有显著的增白作用 ,加入过多将对小麦中的 β -胡萝卜素、维生素A、B、E有较强的破坏作用。为了解学校食堂内的面粉中增白剂过氧化苯甲酰的使用情况 ,加强对学校采购食品原料的管理 ,确保广大学生的身体健康 ,我们于 2 0 0 2年 4～5月份对市属以上学校食堂用面粉进行了 1次检查 ,现将检测情况分析如下。1　调查对象与内容1 1　调查对象　抽取淄博市市属中学及大中专技术 40余所食堂所用的面粉 ,共采集面粉样品 15份 ,其中特二粉 9份 ,特一粉4份 ,高筋精粉 2份 ,涉及 1…     

不同n-3/n-6多不饱和脂肪酸构成比膳食对大鼠一磷酸腺苷活化蛋白激酶表达的影响

目的研究不同n-3/n-6配比脂肪酸对大鼠磷酸腺苷酸活化蛋白激酶(AMP-activated protein kinase,AMPK)蛋白及活性表达的影响。方法58只SD大鼠适应性喂养7d后,尾静脉取血。根据血清总胆固醇水平随机分为:空白(基础饲料);高脂(高脂饲料);高脂1:1(高脂饲料+n-3/n-6=1:1配方油);高脂1:5(高脂饲料+n3/n6=1:5配方油);低脂1:1(脱脂基础饲料+n-3/n-6=1:1配方油);低脂1:5(脱脂基础饲料+n3/n6=1:5配方油)6组,喂养45d,观察大鼠摄食与体重增长。于实验前1d,15d,30d,45d分别各取血测血清总胆固醇水平,于D45处死动物。Western blotting分别分析肝和下丘脑组织中AMPK-α总蛋白及其活性表达。结果添加PUFA的4个比例组血清TC、体重与高脂组相比,显著降低,且低脂2个比例组和高脂1:1组均与高脂1:5组相比有显著差异。添加PUFA的4个比例组均与高脂组相比,大鼠下丘脑AMPK-α总蛋白表达水平明显降低,肝AMPK-α蛋白表达水平均比高脂组明显升高。结论PUFA改善血脂可能是通过增加肝AMPK表达,抑制下丘脑AMPK表达,增加肝脂肪酸氧化和抑制食欲,影响血脂代谢。     

颐养文萃

我国百姓有望吃上营养面粉到2006年,我国老百姓吃面粉就像吃加碘食盐补碘一样,可通过吃面食补充人体所必需的多种微量营养元素。据悉,一项专门针对我国公众身体素质的“7+1”营养强化面粉计划日前在全国面粉行业高峰论坛上正式启动。这是我国“公众营养改善项目”的一个组成部分,也是将来我国面粉生产的一项行业标准。“7+1”营养强化面粉是指在面粉生产过程中添加铁、钙、锌、维生素B1、维生素B2、叶酸以及尼克酸7种基础配方和维生素A建议配方等微量元素。在国际上,对面粉进行营养强化处理已有六七十年历史,美国、加拿大、日本、澳大利亚…     

欢欢喜喜过大年

新年到,新年到,穿新衣,戴新帽,小朋友们哈哈笑……日子过得真快,转眼又迎来了2015年的春节。喜庆团圆的日子里,我们为宝宝精心准备了4款赏心悦目、好吃美味的节日"大餐",希望宝贝们大饱口福,过一个"香喷喷"的春节!蒸蒸日上(小猪馒头)材料面粉250g、牛奶100g、酵母2g、温水25g、红曲粉2g、黑芝麻适量做法1红曲粉放入50g面粉中拌匀,酵母用温水化开分别加入两种面粉中拌匀后,加牛奶揉成光滑的     

用赖氨酸、钙、铁、B_2强化面粉对大鼠生长实验

我们用赖氨酸、钙、铁、B_2等强化面粉对大鼠进行了生长发育和代谢实验,为强化儿童食品提供了科学依据。实验方法实验分为1组(对照组)以武威市食品厂面包成分作为基础饲料:面粉71.1％、白糖14.2％,植物油3.6％,鸡蛋10.7％、食盐0.4％。2组为基础饲料加0.3％赖氨酸。3组为基础饲料加0.3％赖氨酸,钙0.36％、元素铵0.02％、B_20.001％、黄豆粉0。05％。使氨酸色比为400,钙、磷比为1.5:1,以提高蛋白质利用率和钙的吸收。各组配方基本等氮、等热,均经电烤箱200℃烘烤约20分钟,无异味、保持原食品色、香、味。用Wistar种     

不同碳水化合物食品血糖生成指数和胰岛素指数的评估

目的:测定不同来源碳水化合物食品GI值、II值。方法:10名空腹健康志愿者分别试食含碳水化合物50g的葡萄糖粉、富强粉馒头、燕麦纤维馒头和抗性淀粉馒头,测定餐后120min血浆中血糖和胰岛素水平。结果:以葡萄糖GI值、II值分别为100,三种馒头GI值分别为88.24±20.84、60.16±14.16、47.05±10.22;II值分别为83.06±10.81、68.32±17.08、60.26±30.1。食用抗性淀粉馒头后血糖峰值(45min)、胰岛素峰值(60min)及胰岛素与血糖应答曲线下面积比显著低于葡萄糖粉和富强粉馒头(P<0.05),与燕麦纤维馒头相比无统计学意义。燕麦纤维馒头血糖峰值(45min)低于葡萄糖粉(P<0.05)。结论:不同来源的碳水化合物食品有不同的血糖、胰岛素应答,抗性淀粉食品具有吸收缓慢而持久的特点,可维持餐后血糖稳态,降低餐后胰岛素分泌,提高机体对胰岛素的敏感性。     

大豆粉铁对贫血大鼠血红蛋白恢复效应的相对生物利用率

为澄清文献上关于大豆制品不利于膳食铁生物利用率的有争论的观点,本文以硫酸亚铁为参考铁源,某厂试制的猪血粉铁为比照铁,面粉为载体,通过血大鼠模型血红蛋白恢复效应,研究了大豆粉铁的相对生物利用率(RBA％)。实验结果表明:当恢复饲料中3/4 (24/32ppm)铁来自大豆粉、大豆粉面粉各半、猪血粉面粉各半、猪血粉和硫酸亚铁时,贫血大鼠在五周恢复期间血红蛋白恢复效应顺次分别是(g％):6.6至9.4;7.0至10.4;6.1至11.1;6.4至11.4和5.3至12.8。各组铁的相对生物利用率顺次分別为45.4、65.0、72.0、74.0和100％。大豆粉铁的相对生物利用率最低。本文并就此提出一些讨论意见。     

Bioavailability of elemental iron powder in white wheat bread

OBJECTIVE: Iron fortification of wheat flour is widely used. In most cases, elemental iron powders are utilized as fortificants due to their lower cost and few, if any, sensory problems. However, their bioavailability is unknown. We aimed to measure the bioavailability of H(2)-reduced elemental iron powder in white wheat bread made from 72% extraction flour. DESIGN: A stable isotope of H(2)-reduced iron powder (mean particle size 15 microm) was used as fortificant in bread prepared from unfortified wheat flour. In all, 12 5- to 7-y-old children were fed bread with 4 mg of H(2)-reduced (58)Fe /100 g of flour. The next day (57)Fe ascorbate was given as reference dose. After 14 days, erythrocytes were analyzed for isotopic enrichment using mass spectrometry. RESULTS: When normalized to 40% absorption of the reference dose, the geometric mean (+/-range of 1 s.d.) bioavailability of reduced (58)Fe in wheat bread rolls was 6.5% (3.7-11.8). CONCLUSIONS: When compared to previous radioiron studies of ferrous sulfate showing 10% absorption from an identical meal in adult women, the relative bioavailability can be estimated at about 65%. However, the bioavailability of this smaller particle size (58)Fe (15 microm) is likely to be higher than that of commercial iron powder (45 microm) although the precise difference cannot be ascertained with current methods. Thus, the bioavailability of commercial elemental iron powders currently used in fortification programs is likely to be substantially lower than that of ferrous sulfate. SPONSORSHIP: This work was funded in part by Grant No 910313 by Micronutrient Initiative, IDRC, Ottawa, Canada.     

The poor bioavailability of elemental iron in corn masa flour is not affected by disodium EDTA

The most sustainable way to eradicate iron deficiency is through food fortification. Elemental iron powders are commonly utilized as fortificants due to their low cost and few sensory problems. However, their bioavailability is unknown. Our goals were to measure the bioavailability of elemental iron in Mexican style corn masa flour tortillas and to evaluate the effects of Na(2)EDTA. We used a stable isotope of H(2)-reduced iron powder, with and without Na(2)EDTA in tortillas prepared with corn masa flour. Two groups of 5- to 7-y-old children (n = 12/group) were fed tortillas to which was added 3 mg/100 g of H(2)-reduced (58)Fe with a mean particle size of 15 micro m. In one group, Na(2)EDTA was incorporated at a ratio of 1:2 mol/mol. The next day, (57)Fe ascorbate was given as a reference dose. After 14 d, blood samples were analyzed for isotopic enrichment. When normalized to 40% absorption of the reference dose, the geometric mean (+/-range 1 SD) bioavailability of reduced iron in tortilla was 3.8% (2.7-5.3). The addition of Na(2)EDTA, tended to increase it (P = 0.18) to 5.1% (2.8-9.2). This observed low absorption was compounded by the use of iron isotopes with smaller particle size (mean diameter 15 micro m) than typical of commercial elemental iron powder (<45 micro m). We conclude that H(2)-reduced iron powder is an ineffective fortificant in corn tortillas.     

Making bread with sourdough improves mineral bioavailability from reconstituted whole wheat flour in rats

OBJECTIVE: We compared the effects of different kinds of bread fermentation on mineral bioavailability. METHODS: Wistar rats were fed one of the following experimental diets for 21 d: control, reconstituted whole wheat flour (white flour plus bran), yeast bread, and sourdough bread. The apparent mineral absorption and intestinal fermentation were measured in each animal. RESULTS: Phytate contents in yeast and sourdough bread were lower than in reconstituted whole wheat flour (-52% and -71%, respectively). Total cecal pool of short-chain fatty acids, in particular the butyrate pool, was significantly increased by the ingestion of unrefined products. Calcium homeostasis was not modified by these nutritional conditions, whereas magnesium absorption was significantly greater in rats fed the control and sourdough diets than in those consuming whole wheat flour and yeast bread. Magnesium kidney excretion was slightly stimulated by sourdough bread. Compared with the control diet, iron balance was significantly reduced by reconstituted whole wheat flour diet. Yeast bread making counteracted the deleterious effects of whole wheat on iron absorption, whereas sourdough bread making enhanced iron absorption. Further, liver and plasma iron and transferrin saturation levels were lower in rats adapted to the flour diet than in other groups. Zinc absorption was strongly depressed in the presence of unprocessed reconstituted whole wheat flour in the diet, but yeast fermentation afforded a zinc assimilation comparable to the control diet, whereas the sourdough bread led to maximal zinc absorption. Copper absorption increased significantly when rats were fed the sourdough bread, whereas unprocessed whole flour depressed copper absorption (-41% versus control diet). CONCLUSION: Mineral bioavailability from reconstituted whole wheat flour can be improved by bread making. Although yeast fermentation minimizes the unfavorable effects of phytic acid, sourdough bread is a better source of available minerals, especially magnesium, iron, and zinc.     

Phloem fortification in rye bread elevates serum enterolactone level

OBJECTIVE: To analyse the lignan content of phloem powder enriched rye bread and to study the dose-response relationship of the effect of dietary plant lignans derived from phloem on intestinal production of enterolactone by measuring enterolactone concentration in serum. DESIGN: A randomized double-blind supplementation trial. SUBJECTS: Seventy-five non-smoking men recruited by newspaper advertisements. INTERVENTION: Subjects were randomized to three study groups receiving either rye bread high in phloem (HP, 14% of rye flour substituted with phloem powder), rye bread low in phloem (LP, 7% of rye flour substituted with phloem powder) or placebo rye bread. Participants consumed 70 g of study bread daily for 4 weeks and provided serum samples for enterolactone analysis at baseline and at the end of the intervention. RESULTS: There was a significant increase in serum enterolactone concentration in the LP and HP groups compared with the placebo group (P=0.009 and P=0.003, respectively). Considerable interindividual differences were observed in the response to dietary lignans within the study groups. CONCLUSIONS: Our results indicate that plant lignans attached to insoluble fibre layer in phloem can be further metabolized and converted to enterolactone presumably by the bacteria present in the colon. Phloem powder is useful source of lignans for functional foods aimed to elevate serum enterolactone levels. SPONSORSHIP: Phloem powder and the study breads were provided by Finnpettu Oy and Linkosuo Oy, respectively. The clinical study work was sponsored in part by Oy Jurilab Ltd.     

Na2EDTA enhances the absorption of iron and zinc from fortified rice flour in Sri Lankan children

Rice flour was proposed as a vehicle for iron and zinc fortification in Sri Lanka. Although widely consumed, rice flour has not been evaluated as a fortified food, and the absorption of minerals including iron and zinc from this flour is unknown. Determination of the bioavailability of these nutrients is a critical step before commencing a fortification program. We randomly divided 53 Sri Lankan schoolchildren ages 6-10 y into 4 groups that consumed a local dish prepared with 25 g of fortified rice flour labeled with one of the following: 1) (58)FeSO(4) 2) (58)FeSO(4) + Na(2)EDTA 3) (58)FeSO(4) + (67)ZnO or, 4) (58)FeSO(4) + Na(2)EDTA + (67)ZnO. The levels of iron and zinc were 60 mg/kg; the rice flour also contained folate at 2 mg/kg in each group. Na(2)EDTA was added at a Fe:Na(2)EDTA, 1:1 molar ratio. A total of 48 children completed the trial. Absorption of (58)Fe from a meal was significantly greater (P < 0.01) in the groups administered FeSO(4) + Na(2)EDTA (4.7 +/- 3.6%) than in those administered FeSO(4) without Na(2)EDTA (2.2 +/- 1.3%). Fractional absorption of zinc was 13.5 +/- 6.0% in the FeSO(4) + Na(2)EDTA group and 8.8 +/- 2.0% in the FeSO(4) group (P = 0.037). Although zinc absorption was low, our results demonstrated a benefit in using Na(2)EDTA to improve both iron and zinc absorption. We conclude that the fortification of rice flour is feasible, although additional strategies such as dephytinization or an increase in the level of iron and zinc fortification should be considered to obtain a higher proportion of the daily requirement of total absorbed iron and zinc.     

Mulberry (Morus alba) leaves as human food: a new dimension of sericulture

Mulberry leaf is commonly used for sericulture in almost every part of the world but its potential to be utilized for human consumption is not well recognized. This paper deals with development of mulberry leaf powder and its use with wheat flour to develop paratha, the most common food item of breakfast and dinner in the Indian diet. The optimum ratio of the mulberry leaf powder and wheat flour (MLP-WF) mix for preparation of paratha on the basis of sensory quality was found to be 1:4. The protein quality of the MLP-WF mix was estimated by measuring the Protein Efficiency Ratio, and was found to be 1.82 against a casein diet for which a value of 2.44 was observed. The in vivo toxic effect of mix was studied and no adverse effect on the growth of internal organs of rats (heart, liver, kidney and testes) was found. The storage stability of the mix was estimated for a period of 2 months in polyethylene bags at room temperature. A non-significant difference was observed between paratha prepared from fresh and stored mix. This indicated that mix can be stored for a period of 2 months at room temperature without loss of quality.     

蛋白质补充品的研究——Ⅱ.不同加热处理法制备的黄豆粉和花生蛋白粉的营养效用

用理化和生物学的方法对湿热处理黄豆粉、远红外线烘干黄豆粉、膨化黄豆粕粉和用碱液提取后浓缩喷干花生蛋白粉进行了检测,对其蛋白质营养价值进行了综合评定。 2.三种黄豆粉的尿酶和胰蛋白酶活力均为阴性,说明三种加热方法均可使抗营养因子失活。三种豆粉中蛋白质含量在39—49％,每100g粗蛋白质中赖氨酸总量高达6g左右,其中可利用赖氨酸含量湿热处理豆粉为6.05g,远红外烘干豆粉为4.82g,膨化豆粉为5.18g。食膨化豆粉的大鼠的肝、肾,甲状腺、胰腺病理组织学检查未见异常。湿热处理豆粉,远红外线烘干豆粉和膨化豆粉的校正蛋白质功效比值(EPR)(以标准酪蛋白为2.40)分别为2.06、1.86、和1.91,真消化率(TD)分别为91.9、87.2和86.2％,生理价值(BV)分别为67.8、58.8和59.4％,净蛋白质利用率(NPU)分别为62.4、51.3、51.3％,湿热处理豆粉与酪蛋白的校正PER(2.40)、BV(69.9％)和NPU(67.9％)无显著差异,但均显著高于远红外线烘干豆粉和膨化豆粉,这些结果说明这三种加热方法中以湿热处理豆粉的方法较好。 3.花生蛋白粉的蛋白质含量高达70.2％,但氨基酸模式不平衡,缺少赖、苏、蛋、色氨酸。每100g粗蛋白中可利用赖氨酸仅2.89g。校正蛋白质功效比值(PER)为1.32。真消化率(TD)虽高于其他各组,但生理价值(BV)和净蛋白质?