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The impact of nanoparticulated whey protein aggregates on the texture of fat-free set-type yoghurts was investigated. Monodisperse (MFA) and polydisperse (PFA) fractal aggregates obtained from heated whey protein isolate (WPI) were added to skimmed milk for yoghurt manufacture at four different concentrations (0.2%–1.5%, w/w). The impact of the concentration and the polydispersity of the aggregates on fat-free set-type yoghurts were studied by instrumental measurements (rheology, penetrometry, syneresis and microscopy) and sensory analysis. Yoghurt gel strength and firmness increased with the concentration of WPI, MFA and PFA. However, yoghurts enriched with PFA clearly differed from the yoghurts enriched with WPI. Indeed, yoghurts enriched with PFA were characterised by a weak gel, a low firmness and a low-density of the protein network. Sensory analysis confirmed the results obtained by instrumental measurements. The whey protein aggregates studied are thus promising tools to modulate fat-free yoghurt texture while using milk-derived ingredients. 相似文献
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Nan-Nan Liu Zeng-Shan Liu Pan Hu Ying Zhang Shi-Ying Lu Yan-Song Li Yong-Jie Yang Dong-Song Zhang Yu Zhou Hong-Lin Ren 《International journal of molecular sciences》2016,17(8)
Lysophospholipase I (LYPLA1) is an important protein with multiple functions. In this study, the full-length cDNA of the LYPLA1 gene from Ovis aries (OaLypla1) was cloned using primers and rapid amplification of cDNA ends (RACE) technology. The full-length OaLypla1 was 2457 bp with a 5′-untranslated region (UTR) of 24 bp, a 3′-UTR of 1740 bp with a poly (A) tail, and an open reading frame (ORF) of 693 bp encoding a protein of 230 amino acid residues with a predicted molecular weight of 24,625.78 Da. Phylogenetic analysis showed that the OaLypla1 protein shared a high amino acid identity with LYPLA1 of Bos taurus. The recombinant OaLypla1 protein was expressed and purified, and its phospholipase activity was identified. Monoclonal antibodies (mAb) against OaLypla1 that bound native OaLypla1 were generated. Real-time PCR analysis revealed that OaLypla1 was constitutively expressed in the liver, spleen, lung, kidney, and white blood cells of sheep, with the highest level in the kidney. Additionally, the mRNA levels of OaLypla1 in the buffy coats of sheep challenged with virulent or avirulent Brucella strains were down-regulated compared to untreated sheep. The results suggest that OaLypla1 may have an important physiological role in the host response to bacteria. The function of OaLypla1 in the host response to bacterial infection requires further study in the future. 相似文献
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Xin-Hua Sun Gang Yu Jing-Tao Li Pan Jia Ji-Chao Zhang Cheng-Guo Jia Yan-Hua Zhang Hong-Yu Pan 《International journal of molecular sciences》2014,15(8):14891-14906
Many heavy metals are essential for metabolic processes, but are toxic at elevated levels. Metal tolerance proteins provide resistance to this toxicity. In this study, we identified and characterized a heavy metal-associated protein, AcHMA1, from the halophyte, Atriplex canescens. Sequence analysis has revealed that AcHMA1 contains two heavy metal binding domains. Treatments with metals (Fe, Cu, Ni, Cd or Pb), PEG6000 and NaHCO3 highly induced AcHMA1 expression in A. canescens, whereas NaCl and low temperature decreased its expression. The role of AcHMA1 in metal stress tolerance was examined using a yeast expression system. Expression of the AcHMA1 gene significantly increased the ability of yeast cells to adapt to and recover from exposure to excess iron. AcHMA1 expression also provided salt, alkaline, osmotic and oxidant stress tolerance in yeast cells. Finally, subcellular localization of an AcHMA1/GFP fusion protein expressed in tobacco cells showed that AcHMA1 was localized in the plasma membrane. Thus, our results suggest that AcHMA1 encodes a membrane-localized metal tolerance protein that mediates the detoxification of iron in eukaryotes. Furthermore, AcHMA1 also participates in the response to abiotic stress. 相似文献
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水平井开发技术是提高单井产量的有效手段之一.苏家屯油田由于目的层营三(6)砂组为砂泥岩薄互层,6砂组平面分布稳定,但单砂体呈土豆状分布,含油性变化快,单砂体追踪难度大,在水平井地质设计过程中,引入了2种水平井地质设计的方法,为水平井开发砂泥岩薄互层提供水平井地质设计的新思路和新方法. 相似文献
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在隐蔽油气藏勘探中,地震属性的实际运用使得地震信息的充分利用成为可能。地震属性分析就是以地震属性为载体从地震资料中提取隐含的信息,并结合地质、钻井资料,进行储层岩性及岩相、储层物性和含油气性分析。本文针对松辽盆地河山地区三维地震数据提取了营城组和沙河子组的地震属性,通过地震属性与测井曲线和连井剖面对比结合分析了两个时期的沉积特征。 相似文献
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基于摄像机纵向运动的序列图像的实时漫游 总被引:1,自引:0,他引:1
对于摄像机纵向运动的序列图像,提出了一种基于极线几何约束关系的当前视点目标图像生成算法:1)利用基于傅立叶变换的方法,得到远视点源图像中和近视点源图像无对应点的区域,并用一种背景色将其填充,得到填充后的远视点源图像;2)利用极线的整体匹配性质在两幅源图像中确定遍历整个源图像的对应源极线;3)将所有对应源极线按灰度进行分段;4)用动态规划匹配法确定对应源极线上段与段之间的匹配关系;5)通过两条对应源极线插值合成一条目标极线,生成当前视点的目标图像;6)对上一步得到的目标图像的背景色区域加以处理,得到最终的当前视点目标图像.提出了一种链表数据结构存储每相邻两幅源图像之间的预处理信息.漫游时实时读取.开发了一个图像漫游器,使用户能在其中实现不同视点的实时漫游. 相似文献