Enzymatic depolymerisation of starch to glucose or maltose is carried out by starch- degrading amylases during a two-stage hydrolysis: liquefaction using bacterial α-amylase followed by saccharification with glucogenic (fungal amylase) or maltogenic (fungal or bacterial) amylases. As a rule, these enzymes are applied separately, following the recommendations concerning their action provided by the enzyme manufacturers. The study presents our attempts to determine the reaction conditions for a simultaneous action of liquefying and saccharifying enzymes on pre-treated potato starch. Hydrolysis was run by Liquozyme Supra, Maltogenase 4000L and San Super 360L enzymes (Novozymes) at different temperatures. During the single-stage method of starch hydrolysate production the most desirable results was obtained for the maltose hydrolysate at 80°C (51.6 DE) and for the glucose hydrolysate at 60°C (96 DE). The analyses indicate that the application of a single-stage hydrolysis of starch to maltose or glucose makes it possible to obtain a degree of starch saccharification comparable with that obtained in the traditional two-stage hydrolysis.
Synthesis of chiral epoxy resins derived from methyl 4,6-O-benzylidene-á-D-glucopyranoside (1) and epichlorohydrin (2) is described. The strategy involves polyaddition of 2 to 1 catalyzed by NaOH/PTC system at room temperature. The products were analyzed by NMR spectroscopy and the fractions of different functionality were identified by ESI-MS spectrometry.
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Variations in protein, carbohydrate, lipid, ash, moisture, fatty acid and amino acid contents of the seaweeds Ulva lactuca Linnaeus (Chlorophyta), Jania rubens (Linnaeus) J.V. Lamouroux and Pterocladia capillacea (S.G. Gmelin) Bornet (Rhodophyta) were studied seasonally from spring to autumn 2010. The seaweeds were collected from a rocky site near Boughaz El-Maadya on the coast of Abu Qir Bay east of Alexandria, Egypt. Remarkable seasonal variations were recorded in the levels of the studied parameters in the three species. Pterocladia capillacea was characterized by the highest protein and carbohydrate content throughout the different seasons, whereas Ulva lactuca contained more lipids (4.09 š 0.2%) than J. rubens and P. capillacea. The highest total fatty acids were recorded in J. rubens during the three seasons, while saturated fatty acids were predominant in P. capillacea during spring. This is due mainly to the presence of palmitic acid (C16:0), which made up 74.3% of the saturated fatty acids. The highest level of polyunsaturated fatty acids (PUFA) in these algae was measured in J. rubens; DHA (22:6?3) was the main acid, making up 26.4% of the total fatty acids especially during summer. Proline was the major component of the amino acids in the three algal species, with maximum amounts in U. lactuca.
The treatment of type 2 diabetes should be supported with a proper diet paired with physical activity at every stage of therapy. Carbohydrates are key macronutrients with a direct effect on the level of postprandial glycaemia. For the past several decades, dietary intervention studies investigating and comparing the effects of limiting carbohydrate intake in favour of other macronutrients have been carried out. A low-carbohydrate diet has been and still is suggested by some experts as well as patient organizations as the most effective option that is associated with the smallest risk of side effects. The recommendations, however, have not been supported with evidence from high quality randomized control trials. The aim of this work is to review the published meta-analyses of randomized control trials, which compared the parameters relevant for the treatment of diabetes, including fasting plasma glucose, glycated haemoglobin, the lipid profile and weight loss. Currently, there is insufficient scientific evidence allowing a uniform recommendation to be made regarding the optimum amount of carbohydrates in the daily diet, hence the relevant recommendations should be tailored to each patient. In dietary interventions among type 2 diabetes, lowering the patient’s diet energy content is of primary importance, as well as the quality of ingested macronutrients, especially carbohydrates and fats.
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Leczenie cukrzycy typu 2 na każdym etapie powinno być wspomagane odpowiednią dietą połączoną z aktywnością fizyczną. Kluczowym makroskładnikiem diety, mającym bezpośredni wpływ na wzrost glikemii po posiłku, są węglo-wodany. Od kilkudziesięciu lat badane są efekty interwencji dietetycznych polegających na ograniczeniu procentowego udziału węglowodanów w diecie na rzecz innych makroskładników. Dieta niskowęglowodanowa była i nadal jest sugerowana przez niektórych ekspertów oraz środowiska pacjentów jako najskuteczniejsza i niosąca najmniejsze ryzyko skutków ubocznych. Sugestie te nie są jednak poparte dowodami pochodzącymi z wysokiej jakości randomizowanych kontrolowanych badań klinicznych. Praca stanowi przegląd publikowanych w ostatnich latach metaanaliz randomizowanych kontrolowanych badań porównujących parametry mające znaczenie dla leczenia cukrzycy: glikemię na czczo, hemoglobinę glikowaną, lipidogram oraz redukcję masy ciała. Obecnie brak wystarczających dowodów naukowych do zalecania jednej, optymalnej ilości węglowodanów w diecie, wobec czego zalecenia te powinny być indywidualizowane. Większą rolę w podejmowanych interwencjach dietetycznych u chorych na cukrzycę typu 2 mają obniżenie całkowitej wartości energetycznej diety oraz jakość dostarczanych makroskładników, szczególnie węglowodanów i tłuszczów.
The potential erosive effect of enzymes on polycarbonate urethanes has been evaluated. Polyurethanes were obtained in two-stage polyaddition process which involved diisocyanate (TMDI) and poly(carbonate)diol (Desmophen DC2200) The isocyanate prepolymers were crosslinked with carbohydrates (sucrosc, glucose, mannitol, sorbitol) to improve the ability of the enzyme to degrade polymer. Obtained samples were treated by lipase from Candida antarctica (Novozvm 735). Surface characteristic changes after enzymatic degradation were observed using confocal microscopy. The roughness parameters were determined. Also evaluation the degree of changes of the free surface energy was done. In addition, the thermal analysis of pre-degraded and post-degraded residue was performed.