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根据Box-Behnken试验设计原理和响应面分析法确定了富硒大豆中硒蛋白提取的最佳工艺;在此条件下,获取可溶性硒蛋白中的硒代氨基酸,并采用高效液相色谱-质谱联用技术对富硒大豆可溶性蛋白中的硒代蛋氨酸进行定性定量分析。结果表明,液料比11∶1(mL/g)、提取温度 44 ℃、提取时间96 min时,可溶性硒蛋白的提取率可达到76.03%。对4 种自行种植的富硒大豆中可溶性蛋白分析可知:硒-L-蛋氨酸中硒含量与可溶性蛋白中硒含量、富硒大豆中总硒量呈正相关;实验范围内硒代蛋氨酸相对于可溶性蛋白中硒含量最高可达28.46%;说明富硒大豆中不仅含有硒代蛋氨酸,还存在其他形态的硒代氨基酸,有待于进一步研究探索。对大豆进行富硒种植,不仅能提高大豆中含硒总量,而且能通过大豆的生物代谢将其转化成安全无毒营养的有机硒。 相似文献
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硒是一种必需微量元素,具有重要的生理保健功能,利用生物合成方法生产有机硒引起了人们的关注。食用微藻中含有丰富的蛋白质、维生素、脂质、多糖及微量元素等,有显著的营养和保健功能。利用有重要食用和保健功能的小球藻进行硒的富集,进而开发富硒小球藻食品,具有富集效率高,营养丰富、均衡,有多种生理保健功能的特点,因而具有良好的开发潜力和市场前景。 相似文献
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富硒大豆蛋白产品的功能特性 总被引:16,自引:0,他引:16
本文对富硒大豆脱脂粉、富硒大豆浓缩蛋白和富硒大豆分离蛋白的功能特性进行了测定,结果表明:这些产品具有良好的功能特性,适用于食品工业。 相似文献
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纳米硒生物利用度高且研究发现它是毒性最小的硒补充剂。纳米硒具有抗氧化、抗菌功能,可以提高机体的免疫力,具有抗肿瘤作用,可作为癌症预防剂。然而纳米硒在水溶液中容易聚集失活,限制它的生物活性。如何最大限度地保持纳米硒的活性和稳定性成为当前纳米硒的研究热点之一。具有抗氧化性、生物黏附性、无毒性的多糖可作为某些抗菌、抗氧化或营养因子的载体,形成活性复合材料,与纳米硒复合能够有效地增强纳米硒的稳定性,降低硒和多糖应用的局限性。本文综述了当前多糖和纳米硒复合的方法、多糖-纳米硒复合物稳定性的作用机制,并且探讨了多糖-纳米硒复合物的生物活性及应用趋势,为多糖-纳米硒复合物的应用提供了参考依据。 相似文献
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大鼠对亚硒酸钠和硒蛋白生物利用的比较研究 总被引:1,自引:0,他引:1
目的:在营养剂量范围内比较低硒大鼠对亚硒酸钠和硒蛋白的生物利用效果以及剂量-反应关系。方法:雄性SD大鼠72只,按体重随机分为9组,自由进食克山病区低硒饲料。6周后开始对低硒大鼠补硒,对照组每天灌胃纯水;亚硒酸纳、硒蛋白各4组,每天灌胃相应的硒强化剂(各分四个硒剂量2、4、8、16μg/kg bw)。连续灌胃4周后处死采样,通过血肝肾中的硒含量以及肝肾组织中谷胱甘肽过氧化物酶(GSH-Px)活性和硫氧还蛋白还原酶(TrxR)活性来比较生物利用效果。结果:与对照组相比,血肝肾中的硒含量以及肝肾组织中GSH-Px活性和TrxR活性均随补硒剂量的增加而增加(P0.05),呈量效关系。在同一补硒水平上,亚硒酸钠组大鼠肝肾组织中的硒含量高于硒蛋白组(P0.05)。在4g/kg bw剂量时,硒蛋白组大鼠肾GSH-Px活性高于亚硒酸钠(P0.05)。在16g/kg bw剂量时,硒蛋白组大鼠肾TrxR活性高于亚硒酸钠(P0.05)。结论:硒蛋白增加大鼠肝肾组织中的硒含量低于亚硒酸钠,但对含硒酶的影响却优于亚硒酸钠,因此硒蛋白能更好的被大鼠吸收利用。 相似文献
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微量元素硒的研究现状及其食品强化 总被引:21,自引:0,他引:21
综述了微量元素硒的生物学功能、硒缺乏症、硒的毒性、食物中硒的含量与硒的摄入量及硒的营养强化与硒强化食品,并提出了未来硒研究的发展方向。 相似文献
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为研究梭子蟹中硒的赋存形态,并进一步探究梭子蟹硒蛋白组分中硒含量的分布,以梭子蟹为研究对象,采用透析法提取有机硒、连续提取法提取不同种类蛋白质、热水浸提法提取多糖、原子荧光光谱法测定原料和各组分中的含硒量。结果表明:梭子蟹中64.5%的硒是以有机硒形态存在,并主要与蛋白结合(蛋白硒占总硒的48.8%);碱溶性蛋白和水溶性蛋白是梭子蟹结合硒的主要蛋白,总结合硒量占蛋白硒含量的77.9%,按照结合硒量的多少,硒在蛋白中的分布依次是:碱溶性蛋白水溶性蛋白盐溶性蛋白醇溶性蛋白;也有部分硒和多糖结合,占总硒含量的3.59%。 相似文献
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Selenium (Se) is a potent nutritional antioxidant that carries out biological effects through its incorporation into selenoproteins. Given the crucial roles that selenoproteins play in regulating reactive oxygen species (ROS) and redox status in nearly all tissues, it is not surprising that dietary Se strongly influences inflammation and immune responses. The notion that Se "boosts" the immune system has been supported by studies involving aging immunity or protection against certain pathogens. However, studies examining the effects of Se status on other types of immunity such as antiparasitic responses or allergic asthma have suggested more Se may not always be beneficial. In this review, we summarize and compare the available data regarding how the levels of Se affect different types of immunity. Overall, determining how Se intake differentially affects various types of immune responses and dissecting the mechanisms by which this occurs will lead to a better utilization of Se-supplementation for human diseases involving the immune system. 相似文献
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Baliga MS Diwadkar-Navsariwala V Koh T Fayad R Fantuzzi G Diamond AM 《Molecular nutrition & food research》2008,52(11):1300-1304
The availability of selenium and the levels of specific selenoproteins might affect cancer risk by influencing the ability of DNA damaging agents to cause genomic instability and mutations. Transgenic mice that express reduced levels of selenoproteins and previously shown to be more susceptible to pathology associated with cancer development were used to study this possibility. These mice were exposed to X-rays and DNA damage assessed in the erythrocytes, where micronuclei formation was higher compared to the same cells obtained from irradiated wild-type controls. To determine whether the selenoprotein glutathione peroxidase-1 (GPx-1) might be involved in this protection, its levels were reduced by siRNA targeting in LNCaP human prostate cells. UV-induced micronuclei frequency was higher in these cells compared to control-transfected cells. These results indicate a role for selenoproteins in protecting DNA from damage and support human data implicating GPx-1 as a possible target of the chemoprotective effect of selenium. 相似文献
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黑麦中阿拉伯木聚糖对黑麦加工、面包焙烤及营养特性具有重要作用,该文主要讨论黑麦水溶性阿拉伯木聚糖与水不溶性阿拉伯木聚糖的结构、物化性质及营养功能。 相似文献
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Selenium (Se) was discovered 180 years ago. The toxicological properties of Se in livestock were recognized first; its essential nutritional role for animals was discovered in the 1950s and for humans in 1973. Only one reductive metabolic pathway of Se is well characterized in biological systems, although several naturally occurring inorganic and organic forms of the element exist. The amount of Se available for assimilation by the tissues is dependent on the form and concentration of the element. Se is incorporated into a number of functionally active selenoproteins, including the enzyme glutathione peroxidase, which acts as a cellular protector against free radical oxidative damage and type 1 iodothyronine 5'‐deiodinase which interacts with iodine to prevent abnormal hormone metabolism. Se deficiency has been linked with numerous diseases, including endemic cardiomyopathy in Se‐deficient regions of China; cancer, muscular dystrophy, malaria, and cardiovascular disease have also been implicated, but evidence for the association is often tenuous. Information on Se levels in foods and dietary intake is limited, and an average requirement for Se in the U.K. has no been established. Available data suggest that intake in the U.K. is adequate for all, except for a few risk groups such as patients on total parenteral nutrition or restrictive diets. 相似文献
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米糠油或稻米油从很多方面来看都是一种健康植物油。与其他植物油相比,米糠油具有均衡的脂肪酸,拥有较高含量且独特的微量成分、微量营养素或不皂化物。目前研究表明,米糠油中的谷维素含量超过1.5%,提供了营养和药物功能。更多的研究在开展中来证明米糠油多方面的广泛功能。米糠油富含植物甾醇,有许多研究关注其营养应用价值。此外,米糠油含有生育酚和生育三烯酚,尤其后者具有许多特殊功能,如预防乳腺癌等。越来越多地营养学或生物学研究证明,当米糠油适当加工后在食品中使用时,具有特殊功能。因此,在学术研究和产业实践中,都在探索米糠油在食品和制药领域的应用。对米糠油的营养应用进展做简要综述。 相似文献
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Nutritional studies are greatly hampered by a paucity of proper models. Previous studies on nutrition have employed conventional cell lines and animal models to gain a better understanding of the field. These models lack certain correlations with human physiological responses, which impede their applications in this field. Enteroids are cultured from intestinal stem cells and include enterocytes, enteroendocrine cells, goblet cells, Paneth cells, and stem cells, which mimic hallmarks of in vivo epithelium and support long‐term culture without genetic or physiological changes. Enteroids have been used as models to study the effects of diet and nutrients on intestinal growth and development, ion and nutrient transport, secretory and absorption functions, the intestinal barrier, and location‐specific functions of the intestine. In this review, the existing models for nutritional studies are discussed and the importance of enteroids as a new model for nutritional studies is highlighted. Taken together, it is suggested that enteroids can serve as a potential model system to be exploited in nutritional studies. 相似文献
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Milly Ryan-Harshman Walid Aldoori 《Revue canadienne de la pratique et de la recherche en diététique》2005,66(2):98-102
Selenium is an essential trace element involved in several key metabolic activities via selenoproteins, enzymes that are essential to protect against oxidative damage and to regulate immune function. Selenium also may have other health benefits unrelated to its enzymatic functions. It may provide important health benefits to people whose oxidative stress loads are high, such as those with inflammatory or infectious diseases like rheumatoid arthritis or human immunodeficiency virus/acquired immunodeficiency syndrome, or who are at high risk for cancers, particularly prostate cancer. Some studies have generated compelling evidence that selenium is beneficial, either alone or in conjunction with other micronutrients. Additional data from large clinical trials that provide the highest level of evidence will be key to determining the benefits accrued at various selenium intake levels. When the strength of the evidence becomes sufficient, clinical health professionals will need to use dietary and clinical assessment methods to ensure that people at increased risk for cancer or inflammatory and infectious diseases can be appropriately advised about selenium intake. 相似文献