Proteins aggregated into spherulite structures of amyloid fibrils have been observed in patients with certain brain diseases such as Alzheimers and Parkinsons. The conditions under which these protein spherulites form and grow are not currently known. In order to illuminate the role of environmental factors on protein spherulites, this research aims to explore the kinetics and mechanisms of spherulite formation and growth, as monitored by optical microscopy, in a range of salt concentrations, and initial protein concentrations for two model proteins: bovine b-lactoglobulin and insulin. These two proteins are significantly different in their size and fibril growth rate, but both of these proteins have been shown previously to form amyloid fibrils and spherulites under low pH conditions. The...
Abstract -Lactoglobulin (-LG) is a lipocalin, which is the major whey protein of cow's milk and the milk of other mammals. However, it is absent from human milk. The biological function of -LG is not clear, but its potential role in carrying fatty acids through the digestive tract has been suggested. -LG has been found in complexes with lipids such as butyric and oleic acids and has a high affinity for a wide variety of compounds. Serotonin (5-hydroxytryptamine, 5-HT), an important compound found in animals and plants, has various functions, including the regulation of mood, appetite, sleep, muscle contraction, and some cognitive functions such as memory and learning. In this study, the interaction of serotonin and one of its derivatives, arachidonyl serotonin (AA-5HT), with -LG was invest...
The influences of maltodextrin (MD) addition and multi-layer formation on the freeze-thaw stability of ?-lactoglobulin (?-Lg)-stabilized oil-in-water beverage emulsions (0.1 wt% corn oil, 0.006 wt% ?-Lg) were investigated. Various beverage emulsions were prepared depending on MD concentration (0?20 wt%), its dextrose equivalent (M150 or M250), and the presence or absence of additional polysaccharides (pectin, alginate, or ?-carrageenan) coatings around the emulsion droplets. All emulsions (?-Lg- and ?-Lg-polysaccharide-coated emulsions) were unstable to experimental freeze-thaw cycling in the absence of MD. In the presence of MD, all emulsions containing M250 had better stability to droplet aggregation than those with M150, regardless of MD concentrations and freeze-thawing. The optimum co...