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1.
AbstractMicroalgae are unicellular microorganisms that can be rich in proteins and are therefore a valuable ingredient in different foods. So far microalgae are mainly utilized in foods in low concentrations as a whole-cell ingredient even though it is known that proteins extracted from microalgae can possibly posess various technofunctional properties, such as high protein solubility, emulsification, foaming, and gelation properties. The widespread usage of protein-rich ingredients obtained from microalgae is for the most part prevented by the high price of the biomass, the lack of efficient downstream processes, and the adverse taste. The aim of this review is to give insights into the fundamental properties of the growth and processing of microalgae, highlight the advantages of microalgae ingredients and show potential applications based on the technofunctional, nutritional and sensory properties that were reported. Moreover, the existing challenges and knowledge gaps that hinder the application of microalgal proteins in foods are discussed. 相似文献
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H. W. M. Ten Hoopen W. L. J. Hinrichs G. H. M. Engbers J. Feijen 《Journal of materials science. Materials in medicine》1996,7(11):699-704
The effects of sterilization of dry heparinized Cuprophan hemodialysis membranes by means of ethylene oxide (EtO) exposure, gamma irradiation, or steam on the anticoagulant activity and chemical characteristics of immobilized heparin and the permeability of the membrane were investigated. Sterilization did not result in a release of heparin or heparin fragments from heparinized Cuprophan. Sterilization of heparinized Cuprophan by means of EtO exposure and gamma irradiation induced a slight, insignificant decrease of the anticoagulant activity. In contrast, steam-sterilized heparinized Cuprophan showed a higher anticoagulant activity than unsterilized heparinized Cuprophan, which was most likely caused by cleavage of some of the covalent bonds between heparin and Cupropha. The effects of sterilization on the permeability of unmodified Cuprophan and heparinized Cuprophan were compared. The permeability of unmodified Cuprophan for vitamin B12 (Vit B12) and sulfobromophthalein (SBP) was reduced by 20–35% after EtO exposure and gamma irradiation and was reduced by 90–95% after steam sterilization. The water permeability of unmodified Cuprophan remained the same after EtO exposure and gamma irradiation but also dramatically reduced after steam sterilization. These reductions were ascribed to the collapse of pores of the membrane. The permeability of heparinized Cuprophan was not affected by EtO exposure and gamma irradiation but dramatically reduced after steam sterilization, although to a lesser extent than in the case of unmodified Cuprophan. Apparently, the presence of immobilized heparin (partially) prevented the collapse of pores during sterilization. Gamma irradiation was recommended as the preferred method of sterilization for heparinized Cuprophan. 相似文献
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This study was carried out to determine the physical, chemical, microbiological and organoleptic properties of koumiss made from bovine milk. The bovine milk was modified according to the composition of mares’ milk using ultrafiltration, microfiltration and nanofiltration. Koumiss made from modified bovine milk and mares’ milk were compared. In order to assess options for a consistent fermentation, a starter culture, instead of the prevailing spontaneous flora in traditional manufacture of koumiss, was used. Key compositional factors modified were the contents of dry matter, mineral, protein and lactose and the casein-to-whey protein ratio. Koumiss made from modified bovine milk and by starter cultures was found to be very similar to koumiss from mares’ milk in terms of pH, titratable acidity, alcohol, proteolytic activity, apparent viscosity, and microbiological composition, when assessed both in the freshly made product and that after 15 days storage at 4°C. 相似文献
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KU Leo JM Grace Q Li J Peggins AL Mitchell T Aguilar TG Brewer 《Canadian Metallurgical Quarterly》1997,54(5):276-284
Arteether (AE) is primarily deethylated to dihydroqinghaosu (DQHS) in rats and humans. Conversion of AE to DQHS was impaired in microsomes from rats infected with Plasmodium berghei. The Km for AE was 175.1 +/- 49.1 and 124.4 +/- 115.1 mumol/l, and Vmax was 2.24 +/- 0.45 and 1.22 +/- 0.67 nmol AE formed/mg protein/min in control and infected microsomes (p < 0.05), respectively. Calculated intrinsic clearance (CLint = initial Vmax/Km) for AE was only 4% lower in infected microsomes. Apparent pharmacokinetic parameter estimates for AE using the isolated perfused rat liver demonstrated no differences (p > 0.05) in volume of distribution, clearance, and half-life between normal and infected animals. Malaria infection resulted in decreased biliary excretion of free AE and DQHS. The majority of AE is eliminated via biliary excretion of conjugated DQHS, which is approximately 500-fold higher than free DQHS and 75-fold higher than free AE on a molar basis. 相似文献
8.
简介剪切带扩展法(SBP)的原理及其在海底滑坡稳定性分析的应用;以舟山六横岛典型海底斜坡为分析案例,开展基于高斯函数的SBP和极限平衡法(LEM)斜坡稳定性对比分析研究;进行SBP输入参数对剪切带扩展系数R的敏感度分析. 研究结果显示,对于斜坡剪切带破坏长度,当剪切带扩展系数R不大于1时,LEM与SBP得到的滑坡滑裂面区域一致,当R大于1时,SBP计算得到的最终滑动区域比LEM计算得到的区域大;在斜坡发生滑动破坏区域SBP比LEM计算得到的安全系数低;地震影响因素和土体特征位移对R的影响较大. 相似文献
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融合多尺度分块局部二值模式和张量高阶奇异值分解提出一种人脸识别算法.优选不同尺度的MB-LBP算子组合提取图像纹理特征,构造人脸图像的3阶张量模型;利用HOOI算法进行张量高阶奇异值分解;基于HOSVD分解结果采用最邻近算法设计识别分类器.运用Yale数据库和自制数据库进行算法对比实验,验证算法的有效性,实验结果表明,基于Yale数据库,提出算法与LBP深度置信网络算法的识别精度一样高,均为98.667%;基于自制人脸数据库,该算法识别精度为100%.综上提出算法是一种有效的、可行的识别算法. 相似文献