Carbohydrate Material Research Articles

Esterification and interesterification

AbstractA versatile and large group of fatty acid esters are prepared from monohydroxy alcohols (C1 to C22 members), glycols (ethylene and propylene glycols and others), etherglycols (many polyoxyethylene glycols), triols (glycerol and others), tetraols (pentaerythritol and others), polyglycerols, carbohydrate materials (sorbitol, sorbitan, sucrose and others). The two most important direct esterifications of fatty acids are those done with monohydroxy alcohols (methanol, butanol, etc.) and glycerol itself. Esterifications of these materials are carried out with or without the use of catalysts. For edible ester products, the choice of catalyst is determined by (a) rate of reaction promotion permitted by the use of the catalyst; (b) color of product obtained; (c) ease of removal of catalyst; (d) toxicity of catalyst, and perhaps; (e) other factors including promotion of acrolein formation from glycerol, loss by volatilization at high temperatures, inactivation above certain threshold temperatures, and catalyst corrosivity on the materials of construction of the esterifier. In certain instances the last factor may indeed be the paramount one in a particular catalyst choice for a direct esterification. Industrial production of methyl esters is principally by a process of interesterification called methanolysis. Polyols require conditions for complete esterification that are vigorous and severe. The two most important interesterification methods used in the fatty acid industry are the methanolysis of fats and oils for the production of methyl esters and the glycerolysis of fats and oils for the production of three kinds of so‐called “monoglycerides”, namely the 40%, 60% and 90% monoglycerides.

Fractionation of Glucans Synthesized by Streptococcus mutans in vitro

Extracellular polysaccharides (EPS) synthesized by Streptococcus mutans in vitro and insoluble in the culture supernatant are shown to be mixtures of water-insoluble and water-soluble EPS. After dissolving in potassium hydroxide and subsequent neutralization only part of the EPS precipitates (insoluble fraction). Another part can be isolated from the neutralized solution by the addition of ethanol (soluble fraction). Some samples show remarkable amounts of carbohydrate material, soluble even in 70% ethanol or material which can pass dialysis membranes. The insoluble fraction shows a higher share of α-(l→3)-linkages and is less susceptible to dextranase than the soluble fraction. It is suggested that the soluble fraction might be surrounded by insoluble polysaccharide or might be linked to cell-associated glucosyl-transferase, thus becoming part of an insoluble complex. Insoluble EPS synthesized by isolated glucosyltransferase of 5. mutans showed no fractionation after alkaline treatment.

Periodate oxidation analysis of carbohydrates: Part IX. Evaluation of the use of pyridine as reaction solvent for oxidation of water-insoluble carbohydrate materials

Oxidation of methyl glycopyranosides with periodic acid in pyridine was studied by analysis of the reaction products by the dithioacetal method. Both C 2—C 3 and C 3—C 4 bonds were cleaved yielding three types of dialdehydes;secondary attack of these dialdehydes by periodic acid did not occur. Oxidation in aqueous pyridine proceeded in normal Malapradian fashion, but more slowly than for oxidation in water. Molar proportions of aldehydes were theoretical, when methyl glycosides were oxidized with periodic acid in a 1:1 ( v v ) mixture of pyridine and water. The structures of carbohydrate moieties in a few saponins and glycolipids were confirmed by analysis of the oxidation products obtained under similar conditions.

Microbial production of essential amino acid with Corynebacterium glutamicum mutants.

Amino acids produced by microbial process are generally L-forms. The stereospecificity of the amino acids produced by fermentation makes the process advantageous compared with synthetic process. Microorganisms employed in microbial process for amino acid production are divided into 4 classes; wild-type strain, auxotrophic mutant, regulatory mutant and auxotrophic regulatory mutant. Using such mutants of Corynebacterium glutamicum, all the essential amino acids but L-methionine are now being produced by "direct fermentation" from cheap carbon sources such as carbohydrate materials or acetic acid.

A Rhizobium mutant incapable of nodulation and normal polysaccharide secretion

THE surface carbohydrates of Rhizobium, including both the lipopolysaccharide and the extracellular polysaccharide, are thought to participate in the infection and nodulation of legumes by these Gram-negative bacteria1–3. We report here the isolation of a mutant of Rhizobium leguminosarum which produces diminished amounts of extracellular polysaccharide (that is, the carbohydrate material present in cell-free filtrates of bacterial cultures) and which fails to nodulate pea, its normal host.

Biosynthesis of the Blood‐Group‐B‐Specific Trisaccharide in a Rhesus Monkey

A Rhesus monkey, serologically grouped as B, has been shown to excrete low-molecular-weight carbohydrate material in urine closely related to that found in human urine. Galactose feeding resulted in the excretion of a trisaccharide which was shown to be identical to the trisaccharide isolated from the urine of group B humans under the same conditions. Experiments in which [14C]galactose was administered both orally and via an intestinal vein demonstrated that the intestine is the site of biosynthesis.

Barker (neonatal respiratory distress) syndrome in the pig: The ultrastructural pathology of the lung

The ultrastructural pathology of the lung of a naturally occurring, fatal respiratory distress syndrome of the newborn piglet is described. The pulmonary lesions are characterised by immaturity of the distal airways and of alveoli; by severe alveolar epithelial hyperplasia and hypertrophy; by increased width of the blood to air barrier; by alveolar and bronchiolar epithelial degeneration and separation; by the production of alveolar and bronchiolar hyaline membranes and by alveolar haemorrhage and alveolar and peribronchial oedema. Many of the hyperplastic cells of the alveolar epithelium are pyramidal, rest on a basement membrane, have microvilli on their luminal surfaces, form tight junctions with their neighbours and contain reduced numbers of lamellated electron-dense inclusion in the cytoplasm. These cells are dystrophic type 2 pneumocytes. Other hyperplastic alveolar epithelial cells have some of these features and may be type 1 or type 2 pneumocytes. Both types contain large amounts of cytoplasmic carbohydrate material and are deficient in lamellated inclusions associated with type 2 pneumocytes of normal piglets. Increase in the thickness of the blood to air barrier from 0-22 micron to 0-55 micron in normal to 0-50 micron to 2-33 micron in moderately affected piglets, or to a maximum of 12 micron in severely affected piglets, was associated with increasing respiratory distress. Hyaline membranes were composed of epithelial cellular debris from saccular and bronchiolar epithelium. The reduction in size and number of the specific lamellated cytoplasmic inclusions of type 2 pneumocytes in affected lungs was correlated with biochemical findings of increased surface tension and reduced phospholip and lecithin contents of lung washings.

Studies on the Secretion of Maize Root Cap Slime V. The Cell Wall as a Barrier to Secretion

Summary The periodicity of polysaccharide slime secretion by root cap cells of corn ( Zea mays L. cv. SX 17) was studied. The release of carbohydrate material containing hexose and methyl hexose residues from the root of single seedlings has a period of 2–3 hr. Similarly, the release of alcohol insoluble material containing radioactivity from fucose [ 3 H] is cyclic with a period of 2–3 hr. The appearance of label in the incubation medium is preceded by the accumulation of radioactivity in an alcohol insoluble fraction of the tissue homogenate of roots labelled with fucose [ 3 H]. Radioactivity from thymidine [ 3 H] in trichloroacetic acid-insoluble cell debris released from the root cap surface indicates that cell sloughing is also cyclic having a 2–3 hr periodicity. Localization of label by autoradiography in root tips incubated with fucose [ 3 H] for 2 hr showed asymmetric accumulation of radioactivity on the outer tangential surface of cells lying 2–3 cells from the root cap surface. Cytochemical staining of sections of aldehyde-fixed tissue with periodic acid-silver proteinate showed an accumulation of polysaccharide material between the cell wall and plasma membrane of cells lying 2–3 cells from the cap surface. The accumulation of radioactivity and polysaccharide between the cell wall and plasma membrane of these cells is correlated with changes in the structure of the walls. The cell walls of central root cap cells are 0.16–0.20 μm in thickness and possess different silver proteinate staining properties from those of the walls of the peripheral cells which are 0.8–0.9 μm thick. The preferential distribution of several polysaccharide hydrolases in the root cap indicates that they may be involved in alteration of the cell wall. It is proposed that sequential modification of the cell wall by enzymatic hydrolysis results in the periodicity of polysaccharide slime release.

A urinary pentasaccharide in bovine mannosidosis.

Abnormally high amounts of low molecular weight mannose-rich carbohydrate material were found in the urine of an Angus calf with mannosidosis. At least five oligosaccharide fractions were detected by paper chromatography. The most abundant compound was purified by gel chromatography, zone electrophoresis, and two consecutive preparative paper chromatographic steps. The yield was 10 mg/liter of urine. From structural studies including nuclear magnetic resonance spectroscopy, optical rotation, sugar analysis, methylation analysis, and partial enzymatic degradation the following structure was deduced: alpha-D-Manp-(1 leads to 6)-beta-D-Manp-(1 leads to 4)-beta-D-GlcNAcp-(1 leads to 4)-beta-D-GlcNAcp-(1 leads to 4)-D-GlcNAc. This oligosaccharide is distinct from all the oligosaccharides previously described which are excreted by patients with mannosidosis.

Biochemical changes in the transformation of Schistosoma mansoni cercariae to schistosomules

1. 1. In the transformation of Schistosoma mansoni cercariae to schistosomules there was an elimination of the ATEE-hydrolysing proteases to about 50 per cent of the original specific activity level, in 40–60 min. 2. 2. Histochemical examination of the pre- and postacetabular glands of cercariae stained by alizarin and PAS disclosed a similar loss of material as the larvae became schistosomules. 3. 3. The ratio of carbohydrate/protein decreased to about 50 per cent of its original value during the transformation. 4. 4. Extracts of cercariae, tails and bodies submitted to electrophoresis in deoxycholate-containing borate buffer, pH 9·5, disclosed three PAS-stained bands which were identified as post-acetabular gland content, surface coat and glycogen. 5. 5. The loss of carbohydrate material from transforming cercariae was accompanied by changes in intensity of the PAS-stained bands obtained by electrophoresis of larval extracts. 6. 6. The glycoprotein material of the cercarial glycocalyx was recovered from the incubation medium following transformation of the larvae to schistosomules.

Selective micro determination of unconjugated uronic acids by fluorescence reactions with ethylenediamine sulfate

A simple method for the spectrofluorimetric determination of uronic acids is proposed. The fluorescence at 328 (excitation) and 405 nm (emission) formed by heating sample solutions in acetate buffer containing large amounts of ethylenediamine sulfate, can be used to determine 1.0·10 -2–3.0·10 -2 or 4.0·10 -2–4.0·10 -1 μmole of unconjugated uronic acids accurately, without interference from other carbohydrate materials, especially uronides.

The antigens associated with the cell walls of members of the genus Pseudomonas.

Three antigens were associated with the cell walls of pseudomonads. A highly antigenic, strain‐specific antigen of high molecular weight and protein or lipoprotein in nature, occurred as an envelope around the cells. It could be washed off the cells closely associated with carbohydrate material but its antigenicity was not dependent on the carbohydrate present. Another antigen, common to all strains tested, was situated below the first antigen. This was less antigenic than the strain‐specific antigen and was polysaccharide or lipopolysaccharide in nature. A second common antigen was the mucopeptide of the cell walls. This had an antigenicity similar to that of the second antigen and was dependent on both the carbohydrate and polypeptide components of the macromolecule. There appears to be some correlation between these findings and the structure of cell walls of pseudomonads are shown by electron microscopy.

Carbohydrate cytochemistry of the intestinal epithelium of Ascaris suum. Nature of the microvilli glycocalyx and basal lamella.

Results of various cytochemical tests demonstrate large deposits of glycogen within the intestinal absorptive cells of Ascaris suum. Carbohydrate material is also associated with the microvilli surface and basal lamella. Staining produced by the periodate-thiocarbohydrazide-osmium procedure was abolished by analine or m-aminophenol. Diastase digestion did not alter the staining on the microvilli surface. Similar results were seen using the silver methenamine procedure. A positive reaction was noted on the microvilli surface, vesicles in both the apical and basal cytoplasm, Golgi apparatus, and basal lamella. Lanthanum nitrate stained the microvilli surface and intercellular spaces between absorptive cells. Alcian blue or cetylpyridinium chloride in combination with lanthanum enhanced the staining produced by lanthanum alone. These results suggest the presence of acidic glycans on both the microvilli surface and basal lamella.

Aspartylglycosaminuria: a generalized storage disease. Morphological and histochemical studies.

Aspartylglycosaminuria (AGU) is a hereditary metabolic disorder characterized by slowly progressive mental deterioration from infancy, urinary excretion of large amounts of aspartylglycosamine, and decreased activity of the lysosomal enzyme aspartylglcosamine amido hydrolase in various body tissues and fluids. The nature and distribution of the morphological and histochemical alterations in AUG are described in the light of the first AGU patient investigated post mortem and brain and liver. Most nerve cells and hepatocytes contained large vacuoles without any histochemically demonstrable lipid or carbohydrate material. Ultrastructural studies revealed numerous electron-lucent vaculoles, limited by a single, membrane, in the cytoplasm of these cells. In addition to evenly disperesed finely granular or reticular material the vacuoles contained small electron-opaque "lipid" droplets and polymorphic membraneous or granular aggregates. Similar vacuoles were also seen in a number of other cell types, particularly in the kupffer cells and brain macrophages, as well as in the capillary pericytes. Biochemical studies suggest that the principal storage material consists of aspartylglycosamine itself; glycoasparagines of higher molecular weight are present as only minor components. Correlated morphological and biochemical studies thus definitely establish that AGU is a generalized storage disorder. The condition is apparently due to decreased activity of aspartylglycosamine amido hydrolase, with accumulation of products of flycoprotein carabolism in cytoplasmic vacuoles in both epithelial and mesenchymal cells.

Ultrastructural autoradiography and cytochemistry of the iodine‐binding cells in the ascidian endostyle

AbstractThyroid‐like activity was investigated in the endostyles of Molgula manhattensis, M. occidentalis and Styela plicata. Animals were immersed in sea water containing 125I for one to 24 hours. Although electron microscopic autoradiography revealed an extracellular accumulation of silver grains associated with zone 8 in all three species and with zone 9 in two of them, intracellular accumulations were found only in zone 7. Within this zone in each of the three species, grains were present over the apical cell membrane, multivesicular bodies and the apical cytoplasmic matrix after brief exposure to 125I. After longer exposure, grains were also present over large dense bodies and more basal regions of the cytoplasmic matrix.Certain features, suggestive of thyroidal functions, were observed in the cells of zone 7. These included morphological evidence for secretory and pinocytotic activities and cytochemical evidence both for peroxidase activity and for the presence of carbohydrate material which may represent a glycoprotein.It is concluded that active binding of iodine is restricted to zone 7 in the endostyles of Molgula and Styela, where it occurs at both the apical cell membrane and within multivesicular bodies. Some of the iodinated product may be immediately passed into the lumen of the pharynx. The rest is stored intracellularly within multivesicular bodies and dense bodies of zone 7. Intracellular binding and storage of iodine are considered to represent primitive conditions preceding the evolution of the follicular structure of the thyroid gland.

The amino-acid composition of human hard tissue collagens in osteogenesis imperfecta and dentinogenesis imperfecta.

Collagen from the calvarium of a 2-week-old infant with osteogenesis imperfecta and dentine collagen from a first permanent molar of an 11-year-old boy with dentinogenesis imperfecta were prepared by methods which had previously been used for collagens from normal hard tissues. Amino-acid analysis, carried out on hydrolysates of these preparations, showed the same amino-acids as are found in normal collagens. There was no gross deficiency in any particular amino acid and the compositional differences accompanying the pathological conditions appeared to be small. The collagen from osteogenesis imperfecta had a 7–9% deficiency in the abundant amino acids and an excess of amino acids with lipophilic side chains, compared with collagen from normal bone, which suggested that up to 10% of other protein material could be present in osteogenesis imperfecta. In dentinogenesis imperfecta there was a similar but smaller decrease in the amounts of hydroxyproline and alanine but there was an increase in the amounts of glycine and proline present. An excess of hydroxylysine was found in both diseased states compared with the corresponding normal hard tissue collagens. A 12% deficiency in weight recovery compared with nitrogen recovery may be explained by carbohydrate material responsible for argyrophilia.

Studies in cystic fibrosis. Urinary excretion of hexosamine, sialic acid and fucose.

SummaryNormal values for the total urinary excretion of hexosamine, sialic acid and fucose and their ratios to creatinine in childhood were determined. The excretion of these substances in 25 CF children was slightly higher at all ages than in controls. The increase was more pronounced in higher ages and in more severely affected patients.No difference in the ratio of fucose to sialic acid was found between controls and CF patients, either in the unfractionated urine or in the ultrafiltrable or non‐ultrafiltrable fractions of urine.Zone electrophoretic fractionation of the non‐ultrafiltrable material disclosed a proportionately higher excretion of both carbohydrate‐ and protein‐containing material in CF patients as compared with controls.Two CF patients exhibited normal gel‐chromatographic distributions of fucose‐con‐taining low molecular weight carbohydrate material.

The histochemical detection of soya "novel proteins" in comminuted meat products.

The enforcement of the regulations governing meat and meat products requires the determination of meat content. Meat content is assessed from the total nitrogen content, from which suitable deductions are made for the nitrogen contributed by the other ingredients of significant nitrogen content present in meat and meat products. The availability of “novel proteins” and the possibility of the addition of these proteins to meat products necessitates the detection and determination of “novel proteins” in such products for the true assessment of their meat content. A microscopical method that indicates the presence of “novel protein” of soya origin in meat products has been examined. This method involves the use of a specific technique to demonstrate the presence of carbohydrate material and is diagnostic for the cellular fraction of many processed soya products.

A New Approach for the Evaluation of Wood from Fertilized Trees

A new approach is presented to evaluate the effects of fertilizer application on wood properties of Douglas-fir, in particular weight of tracheid and its length. A specially developed quartz ultra-microbalance was used to weigh tracheids (holocellulose and alpha cellulose skeletons), from wood formed by trees treated with four different formulations (urea, NPK, (NH4)2SO4, NH4NO3).Following the year of fertilization, tracheid weight decreased or remained static for 1 or 2 years; subsequently there was an increase in the weight of individual cells. Highly significant correlations (R2 more than 64%) were found between length of tracheid and weight of carbohydrate material in it. Variations in cell weight following fertilizations, for the most part, were associated with changes in tracheid length.Although the study was not intended as a statistical sampling for the species, the results nevertheless illustrate that qualitative differences attributable to treatment composition (urea vs. NPK vs. (NH4)2SO4) exist, in that some treatments resulted in less weight of alpha cellulose per unit length of tracheid, when compared with normal wood tracheids. This reduction in cellulose fraction was suggested as a possible factor for differences observed in gross wood specific gravity in wood of some fertilized trees.

Characterization of Mannide Monooleate

Two lots of a specially treated mannide monooleate emulsifier were fractionated by column chromatography and characterized by TLC and GC; individual components were identified by mass spectrometry. Silica gel fractionation indicated the presence of three major classes of components: diesters, monoesters, and polymeric carbohydrate material. The diester contents of Lots 114B and 115B were 36.3 and 51.8 wt. % while the monoester content was 52.2 and 31.4 wt. %, respectively. The carbohydrate polymer content amounted to 11.2 and 15.8 wt. %, respectively. The mannide monooleate (as the chemical entity) content within Lots 114B and 115B was 33.6 and 20 wt. %, respectively, while the mannide dioleate content varied from 21.9 wt. % (114B) to 29.2 wt. % (115B). Six cyclic fatty acids were observed in these two lots as well as in two toxic lots identified as 8B and 3589. The UV absorptions at 267, 278, 298, and 315 nm. were approximately fivefold greater for Lot 8B than Lot 114B and approximately 20‐fold greater for Lot 3589. Nonconjugated trans‐olefins were present in Lots 114B and 115B to the extent of 5.9 and 6.0 wt. %, respectively, while the conjugated tratts‐trans‐diene content amounted to about 1.6 wt. % for both specially treated lots. In both lots, 14 components were found to comprise the monoester class, while 13 components comprised the diester class. The carbohydrate material was not characterized.