180 research outputs found
Effect of sialidase on blood group specificity of hog submaxillary glycoproteins
Hogs can be divided into three phenotypes A, H and In, depending on the ability of extracts of their submaxillary glands to inhibit the agglutination of human A cells with human anti-A, and human O cells with eel-anti-H serum. Evidence is here provided that the inactive glycoprotein, In, represents H active glycoprotein containing additional N-glycolyl neuraminic acid, which stereospecifically masks the H determinant, [alpha] (1 --> 2)-L-fucosyl residue.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32733/1/0000101.pd
Quantitative determination of reducing sugars, oligosaccharides, and glycoproteins with [3H]borohydride
A very simple and direct radioactive isotope method has been described for the quantitative determination of reducing sugars. The method can be adapted to give any degree of sensitivity desired. The procedure is of general applicability to the determination of a large class of sugars. The stoichiometry of the reaction makes it a comprehensive procedure which greatly facilitates the analysis of sugars, oligosaccharides, and glycoproteins after acid and enzymic hydrolysis. Examples of the versatility of the method are given.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33817/1/0000074.pd
Valorization of pineapple waste for the extraction of bioactive compounds and glycosides using autohydrolysis
Autohydrolysis process, an alternative technology that uses only water as extraction solvent, was evaluated for the extraction of glycosides and polyphenols from pineapple waste. A Box-Behnken design was carried out using different temperatures (150200°C), solid-liquid ratio (1:401:10w/v) and reaction time (1545min). The best condition for the production of glucose (27.6g/L) and fructose (33.8g/L) was 150°C, 30min and 1:10w/v while the highest amount of extracted total polyphenols (1.75g/L) was obtained at 200°C, 30min and 1:10w/v solid-liquid ratio. In all treatments were detected gallic acid, hydroxybenzoic acid, chlorogenic acid, epicatechin, coumaric acid and caffeic acid. These results indicate autohydrolysis as a valuable alternative for the sustainable extraction of high value-added molecules for further use in industrial, food, cosmetic and health applications.The authors thank to BiValBi (Biotechnologies to Valorize the regional food Biodiversity in Latin America) project with reference PIRSES-GA-2013-611493 by financial support. J.A. Teixeira and A. Romaní thank financial support obtained by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-010145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145FEDER-000004) funded by European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio
Fucoidan-degrading fungal strains: screening, morphometric evaluation, and influence of medium composition
Ten different fungal strains from the genus Aspergillus, Penicillium, and Mucor
were screened for fucoidan hydrolyzing ability aiming to find microorganisms able to
produce sulfated fucan-degrading enzymes. Screening was carried out by measuring the
strains kinetic and morphometric behavior over plate assays using Laminaria japonica
fucoidan as only carbon source, testing three nitrogen sources (urea, peptone, and sodium
nitrate). The selected fungal strains were subsequently used in submerged fermentations,
which were performed for (1) selection of the strains able to growth over fucoidan medium
and (2) media selection, testing the synergy of fucoidan with other sugars for inducing high
enzyme titles. Radial expansion and hyphae parameters were observed for Aspergillus niger
PSH, Mucor sp. 3P, and Penicillium purpurogenum GH2 grown only over fucoidan-urea
medium. A. niger PSH showed the maximum enzymatic activity values, which were
significantly different (p<0.05) from those achieved by the other selected fungi. Sucrose
addition to fucoidan media proportioned the highest fucoidanase activity values for this
fungal strain. This research allowed establishing optimal conditions for metabolites
synthesis by fungal stains able to act toward fucoidan ramified matrix.Mexican
Science and Technology Council (CONACYT
Effects of defatted dried roselle (Hibiscus sabdariffa L.) seed powder on lipid profiles of hypercholesterolemia rats.
BACKGROUND: In vivo investigations were made of the effect of defatted dried roselle seed powder (DRS) on the lipid profiles of rats with induced hypercholesterolemia. The two-batch sample consisted of 23 and 20 Sprague-Dawley male rats randomly divided into four groups and fed with four different diets. The first batch of rats was fed with normal, hypercholesterol, hypercholesterol + 10 g kg-1 (w/w) DRS and hypercholesterol + 20 g kg-1 (w/w) DRS diets. The second batch of rats was fed with normal, hypercholesterol, hypercholesterol + 50 g kg-1 (w/w) DRS and hypercholesterol + 150 g kg-1 (w/w) DRS diets. Treatments were given for a total of 5 weeks.
RESULTS: Results indicated that the addition of 10 g kg-1 and 20 g kg-1 of DRS did not significantly lower the plasma total cholesterol (TC) levels. In contrast, 50 g kg-1 and 150 g kg-1 DRS significantly lowered (P < 0.05) the TC and low density lipoprotein cholesterol (LDL-C) levels.
CONCLUSION: The addition of 50 g kg-1 and 150 g kg-1 DRS showed potential hypocholesterolemic effects. Furthermore, these findings indicated that protein, lipid and dietary fibre were high in the seed powder
Production, chemical characterization, and sensory profile of a novel spirit elaborated from spent coffee ground
This study describes a process for the production of a spirit from spent coffee ground (SCG), the chemical composition, and sensory profile of this distillate. The process consisted in three steps starting with the extraction of aroma compounds by hydrothermal treatment of SCG, followed by the fermentation of this extract supplemented with sucrose to ethanol, and the fermented broth distillation. Seventeen volatile compounds were identified in the distillate (including alcohols, esters, aldehydes, and acids), all of them in concentrations able to promote pleasant characteristics to the product. Based on the chemical composition, \SCG\ spirit was considered as having organoleptic quality acceptable for human consumption. Twelve descriptors defined the sensory characteristics of this product, including clarity and brilliance (visual analysis), coffee, roasted, alcohol, elegance and frankly (olfactory analysis), bitter, astringent and pungent (gustatory analysis), and finesse (olfactory and gustatory analyses). Coffee was the most representative aroma by olfactory analysis. Based on the sensory analysis, \SCG\ spirit was considered as having features of a pleasant beverage, with smell and taste of coffee
Isolation and characterization of a glycopeptide from human senescent erythrocytes
A glycopeptide (called "senescence-factor glycopeptide", SF-G) has been isolated from a tryptic digest of human erythrocytes by specific adsorption and elution from immobilized peanut lectin. SF-G was detectable in old but not in young erythrocytes isolated from the same unit of blood. It is present in small quantities, O-glycosyl type, being released by an endo-N-acetyl-[alpha]--galactosaminidase.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25133/1/0000566.pd
Iduronic acid: constituent of sulphated dolichyl phosphate oligosaccharides in halobacteria
The occurrence of iduronic acid in the cell surface glycoprotein of halobacteria is described. This hexuronic acid is not only found in protein-linked oligosaccharides in halobacteria but does also exist in the corresponding dolichol-linked precursors. These findings were unexpected, as iduronic acid is a typical constituent of animal glycosaminoglycans, and its biosynthesis is so far known to occur by epimerization of a glucuronic acid residue within the completed carbohydrate chain linked to protein
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