Kinetics of lactose hydrolysis and galactooligosaccharides formation in beverages based on goat’s milk and its permeate

Food Science and Biotechnology - The aim of this work was the analysis of galactooligosaccharides (GOS) formation in a model mixture of goat’s milk and its permeate from microfiltration and...     

Production of dihydroxyacetone from an aqueous solution of glycerol in the reaction catalyzed by an immobilized cell preparation of acetic acid bacteria Gluconobacter oxydans ATCC 621

Dihydroxyacetone (1,3-dihydroxy-2-propanone, DHA) is applied in the food and cosmetic industries as well as in pharmacy and medicine. It is produced as a result of incomplete oxidation of glycerol by acetic acid bacteria Gluconobacter oxydans. This reaction is catalyzed by PQQ-dependent membrane-bound glycerol dehydrogenase. The research developed a method of obtaining DHA by oxidation of a 3?% aqueous solution of glycerol (pH 7.5) at a temperature of 23?°C, with the only reaction biocatalyst being an immobilized cell preparation obtained from G. oxydans cells. After 5?days of the process, DHA concentration in the solution accounted for 27.2?g/L and the reaction efficiency for 94?%. After 4?days of the reaction run in culture media with pH 5.0, at a temperature of 28?°C, free or immobilized cells of G. oxydans produced on average 25?g of DHA/L at the reaction efficiency of 87?%.     

Stability of emulsions formulated with high concentrations of sodium caseinate and trehalose

Stability of emulsions formulated with 10 wt.% oil (concentrated fish oil, CFO, sunflower oil, SFO, or olive oil, OO), sodium caseinate concentrations varying from 0.5 to 5 wt.%, giving oil-to-protein ratios of 20–2, and 0, 20, 30 or 40 wt.% aqueous trehalose solution was studied by Turbiscan. Particle size distribution, microstructure, and small angle X-ray scattering (SAXS) patterns were also obtained. The main mechanism of destabilization in a given formulation strongly depended on oil-to-protein ratio. As evidenced by the BS-profile changes with time, emulsions formulated with 0.5 and 1 wt.% NaCas destabilized mainly by creaming while for the 2 wt.% NaCas concentration, both creaming and flocculation mechanisms, were involved. The main destabilization mechanism for the 3, 4 or 5 wt.% NaCas emulsions was flocculation. Stability of emulsions was also affected by the content of trehalose in the aqueous phase. Trehalose diminished the volume-weighted mean diameter (D_4,3) and greatly improved stability.     

Renal glomerular and tubular lesions in rabbits treated with uranyl nitrate

Renal injury and regeneration was followed light--and electron microscopically in rabbits treated with uranyl nitrate. The presence and importance of glomerular lesions is noteworthy.     

Transplantation of Peyer''s patches under the kidney capsule in syngeneic mice. I. Morphological studies

The morphology of Peyer's patches transplanted under the kidney capsule in syngeneic mice was studied up to 30 days after transplantation. Changes undergoing in transplants were arbitrarily divided into three stages: the initial stage of necrosis, then from the third day on -- clearing of dead tissues, and finally, from the fifth day -- lymphoid regeneration. Starting from the ninth day on, the lymphoid structure of the transplants was quite distinct. Transplants appeared to be similar to Peyer's patches in situ. Reconstituted transplants contained a huge number of blood vessels located with lymphocytes. The epithelial cysts were found in all the transplants. They were formed by remnants of persisted intestinal epithelium covering Peyer's patches in situ. The possibility of epithelial influence on lymphoid regeneration of the transplants is discussed.