蜜源油菜花粉有效成份的研究

油菜(Brassica campestrisLinn.var.oleifera DC.)花粉含有七种可溶性糖和一个中性多糖;十七种游离氨基酸和十八种水解氨基酸;十一种维生素;四种黄酮类化合物;九种脂肪酸;五种有机酸和廿二种矿质元素。因此,油菜花粉是一种营养与有效成份极其丰富的营养品。     

Chemical Studies on the Cell Walls of Leptospira biflexa Strain Urawa and Treponema pallidum Strain Reiter

The preparation and chemical poperties of the cell walls of Leptospira biflexa Urawa and Treponema pallidum Reiter are described. Both cell walls are composed mainly of polysaccharides and peptidoglycans. The data of chemical analysis indicate that the cell wall of L. biflexa Urawa contains rhamnose, arabinose, xylose, mannose, galactose, glucose and unidentified sugars as neutral sugars, and alanine, glutamic acid, α,ε-diaminopimelic acid, glucosamine and muramic acid as major amino acids and amino sugars. As major chemical constituents of the cell wall of T. pallidum Reiter, rhamnose, arabinose, xylose, mannose, galactose, glucose, alanine, glutamic acid, ornithine, glycine, glucosamine and muramic acid have been detected. The chemical properties of protein and polysaccharide fractions prepared from the cells of T. pallidum Reiter were also partially examined.     

Sugars in hydrolysates of fungal melanins and soil humic acids

Humic acids from four Brazilian topsoils of different origin and four fungal melanins, synthesized under two cultural conditions were subjected to a two step hydrolysis procedure and the released monosaccharides qualitatively and quantitatively determined by gas-liquid chromatography. The neutral sugars, glucose, galactose, mannose, arabinose, xylose, fucose, rhamnose and the alcohol sugar inositol, were detected in most of the soil humic acid samples. The fungal melanins showed the presence of glucose, galactose, mannose and arabinose. Ribose was present in two out of the eight samples tested. Some quantitative differences in the two types of humic polymers were noted and expected considering their origins. However, similarities were more apparent than differences and give further indication that melanic fungi may play a significant role in the formation of soil humic acids.     

Production and composition of extracellular polysaccharide from cell suspension cultures of Mentha

A suspension culture of Mentha was established from callus which formed on the tips of young shoots of a Mentha hybrid (M. arvenis × M. spicata). Changes in growth parameters during a culture cycle were recorded. The general appearance of cells during division and growth, including the changes in cell form, was also represented.Suspension-cultured cells of Mentha hybrid released a large amount of extracellular polysaccharides (ECP) mainly at the logarithmic phase of the growth cycle. The ECP contained galacturonic acid as major components and arabinose, galactose, glucose, xylose, rhamnose and mannose as minor components. The ratio of the uronic acid content to total sugar content in the ECP was below 40% at day 7, but increased up to 90% at day 21. The relative contents of xylose and glucose in the ECP decreased during the culture period, while the arabinose content increased and those of rhamnose, mannose and galactose remained constant.The IR spectrum suggested that the ECP were low-methoxylated pectic polysaccharides. The presence of lignin and related compounds in the ECP was not detected. The protein content of the ECP was about 10% and the main amino acids were alanine, proline, hydroxyproline, valine, asparticacid and serine, in that order.     

Chemical characterisation of the released polysaccharide from the cyanobacterium Aphanothece halophytica GR02

The released polysaccharide from the halophilic cyanobacterium Aphanothece halophytica GR02 was separated into two main fractions byanion-exchange chromatography. The major fraction consisted of glucose,fucose, mannose, arabinose and glucuronic acid. Judging from thechromatography on Sepharose 2B, the major fraction was not furtherfractionated, and its apparent molecular weight was above 2.0 × 10⁶ Da.The minor fraction consisted of rhamnose, mannose, fucose,glucose, galactose and glucuronic acid, with traces of arabinose.Methylation and GC-MS spectrometry analyses of the major fractionrevealed the presence of 1-linked glucose, 1,3-linked glucose, 1,3-linkedfucose, 1,4-linked fucose, 1,3-linked arabinose, 1,2,4-linked mannose,1,3,6-linked mannose, 1-linked glucuronic acid and 1,3-linked glucuronicacid residues. The major fraction was thought to originate from capsularpolysaccharide. The released polysaccharides, obtained from cultures atdifferent age of culture, showed no striking variations in themonosaccharide composition and the relative proportions of themonosaccharides. However, the proportions of galactose and rhamnose inthe released polysaccharides, obtained from cultures under different salinity,were significantly different. The released polysaccharide also exhibitedgelling properties and strong affinity for metal ions.     

Cell wall and sheath constituents of the cyanobacterium Gloeobacter violaceus

Sheaths isolated from Gloeobacter violaceus were found to be composed of a major polysaccharide moiety (glucose, galactose, rhamnose, mannose, arabinose), a protein moiety, and negatively charged components (glucuronic acids, phosphate, sulfate). Outer membrane polypeptide patterns were dominated by two major peptidoglycan-associated proteins (M_r 62,000 and 53,000). Lipopolysaccharide constituents were glucosamine, 3-hydroxy fatty acids (3-OH-14:0, anteiso-3-OH-15:0, 3-OH-16:0, 3-OH-18:0), carbohydrates, and phosphate. A1-type peptidoglycan and non-peptidoglycan components (mannosamine, glucose, mannose, and glucosamine) indicated the presence of a peptidoglycan-polysaccharide complex in the cell walls of Gloeobacter violaceus.Abbreviations A₂pm diaminopimelic acid - ATCC American Type Culture Collection - CE cell envelope - CM cytoplasmic membrane - CW cell wall - dOcla 3-deoxy-d-manno-2-octulosonic acid - GalN galactosamine - GlcN glucosamine - GlcUA glucuronic acid - HF hydrofluoric acid - LPS lipopolysaccharide - ManN mannosamine - M relative molecular mass - MurN muramic acid - MurN-6-P muramic acid-6-phosphate - OMe O-methyl - PAGE polyacrylamide gel electrophoresis - PCC Pasteur Culture Collection - SDS sodium dodecyl sulfate - SH sheath     

Production of citric acid from sugars present in wood hemicellulose usingAspergillus niger andSaccharomycopsis lipolytica

Summary One strain each of the fungus,Aspergillus niger, and the yeast,Saccharomycopsis lipolytica, were investigated for their ability to produce citric acid from the sugars present in hemicellulose hydrolysates.S. lipolytica produced citric acid as efficiently from mannose as from glucose, but failed to assimilate xylose, arabinose or galactose.A. niger readily assimilated mannose, xylose and arabinose, and produced citric acid from these sugars although the yields were lower than from glucose. A possible inhibitory effect of arabinose on citric acid production from other sugars was observed usingA. niger.     

Isolation and characterization of an extracellular hydroxyproline-rich glycoprotein and a mannose-rich polysaccharide from Eudorina californica (Shaw)

Mucilage and colony walls of E. californica were separated from the cells by homogenization, filtration, and differential centrifugation. The chief components of the mucilage were a high-molecular-weight (MW) hydroxyproline-rich glycoprotein and a very high-MW polysaccharide in the proportions 47% and 34%, respectively. The glycoprotein consisted of galactose, arabinose, xylose and an unidentified neutral sugar; and the amino acids cysteine, aspartic acid, glutamic acid, arginine, lysine, glycine, serine, methionine, histidine, alanine, proline, hydroxyproline, tyrosine, threonine, valine, phenylalanine, isoleucine and leucine. The principal sugar of the polysaccharide was mannose. The chemical composition of the colony walls was essentially the same as that of the glycoprotein in the mucilage except that there was almost twice as much hydroxyproline. Also the protein content of the colony walls was 34% while that of the glycoprotein in the mucilage was 22%. No glucose, sugar acids or nucleic acids were found in the extracellular matrix.     

Growth of five pathogenic fungi on cell wall-related monosaccharides

Spores of Monilinia fructicola, Colletotrichum coccodes, Botrytis cinerea, Alternaria alternata and Mucor mucedo were transferred to agar plates containing 0.5, 5 or 50 mM concentrations of various plant cell wall-related monosaccharides or glucose. The wall-related monosaccharides tested were arabinose, galactose, galacturonic acid, mannose, rhamnose and xylose. Germ tube length was measured after 24 h. Growth of germ tubes on media containing the different monosaccharides varied substantially among fungi. The most striking response was with M. mucedo; spores were only able to grow on media containing glucose or galactose.Increase in colony size was determined during a 7-day period after subcultures were transferred to media containing 5 mM arabinose, galactose, galacturonic acid, mannose, rhamnose and xylose, each with and without 5 mM glucose. Glucose, alone or in conjunction with any other monosaccharide, was the optimal carbon source for growth. In general, fungi were unable to grow as well on any of the wall-related monosaccharides without glucose. Galacturonic acid and rhamnose, major components of pectic polysaccharides of plant cell walls, were unable to support any growth of M. fructicola cultures. No wall-related monosaccharides supported more than 50% of the growth observed when M. mucedo cultures were grown on glucose.     

Purification and characterization of fish surface mucin

Fish surface mucin from Pampus argenteus was extracted with different organic solvents and the residue passed through Sephadex G-200. The major peak was purified by DEAE-Cellulose chromatography and five fractions were obtained. Carbohydrate and protein contents showed that major peak is a glycoprotein. Rechromatography of this component on the Sephadex G-200 column gave a single peak, with an estimated minimal molecular weight of 6.9 X 10(5). Analysis of individual sugar components revealed the presence of galactose, glucose, mannose, arabinose, N-acetyl glucosamine, N-acetyl galactosamine and sialic acid. The most represented amino acids are threonine, serine, proline, glutamic acid and glycine. The N-terminal amino acid end was blocked. Nearly 47% of sulphate was acid labile. Sialic acid and fucose were released rapidly by mild acid hydrolysis. The presence of blood group-A activity suggests that some kind of terminal alpha-Gal-NAC may be present.