INFLUENCE OF AGE AND STAGE OF DEVELOPMENT ON THE NEUTRAL CARBOHYDRATE COMPONENTS IN ROOT EXUDATES FROM ALFALFA PLANTS GROWN IN A GNOTOBIOTIC ENVIRONMENT

1972 ◽  
Vol 52 (4) ◽  
pp. 633-642 ◽  
Author(s):  
R. A. HAMLEN ◽  
F. L. LUKEZIC ◽  
J. R. BLOOM

Investigations were carried out by gas–liquid chromatography–mass spectrometry on the neutral carbohydrate fraction of root exudates from DuPuits alfalfa plants grown gnotobiotically for 16 weeks. Carbohydrates detected were arabinose, ribose, xylose, fructose, mannose, glucose, inositol, sucrose, and maltose. Three components were not identified. A general trend was observed of decreasing concentration of total neutral carbohydrates released with increasing plant age; however, two components increased with time. Based on milligrams of carbohydrate released per gram of dry weight of root tissue, all carbohydrates decreased with increased plant age. Flowering plants produced a significant increase in amounts of material released over samples from clipped plants. The results support the view that age and stage of development are significant influences on the qualitative and quantitative nature of plant root exudates.

1968 ◽  
Vol 108 (3) ◽  
pp. 401-412 ◽  
Author(s):  
R. P. Longley ◽  
A. H. Rose ◽  
B. A. Knights

1. Protoplasts of Saccharomyces cerevisiae N.C.Y.C. 366 were prepared by incubating washed exponential-phase cells in buffered mannitol (0·8m) containing 10mm-magnesium chloride and snail gut juice (about 8mg. of protein/ml. of reaction mixture). Protoplast membranes were obtained by bursting protoplasts in ice-cold phosphate buffer (pH7·0) containing 10mm-magnesium chloride. 2. Protoplast membranes accounted for 13–20% of the dry weight of the yeast cell. They contained on a weight basis about 39% of lipid, 49% of protein, 6% of sterol (assayed spectrophotometrically) and traces of RNA and carbohydrate (glucan+mannan). 3. The principal fatty acids in membrane lipids were C16:0, C16:1 and C18:1 acids. Whole cells contained a slightly greater proportion of C16:0 and a somewhat smaller proportion of C18:1 acids. Membrane and whole-cell lipids included monoglycerides, diglycerides, triglycerides, sterols, sterol esters, phosphatidylcholine, lysophosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol+phosphatidylserine. Phosphorus analyses on phospholipid fractions from membranes and whole cells showed that membranes contained proportionately more phosphatidylethanolamine and phosphatidylinositol+phosphatidylserine than whole cells, which in turn were richer in phosphatidylcholine. Phospholipid fractions from membranes and whole cells had similar fatty acid compositions. 4. Membranes and whole cells contained two major and three minor sterol components. Gas–liquid chromatography, mass spectrometry and u.v. and i.r. spectra indicated that the major components were probably Δ5,7,22,24(28)-ergostatetraen-3β-ol and zymosterol. The minor sterol components in whole cells were probably episterol (or fecosterol), ergosterol and a C29 di-unsaturated sterol. 5. Defatted whole cells contained slightly more glutamate and ornithine and slightly less leucine and isoleucine than membranes. Otherwise, no major differences were detected in the amino acid compositions of defatted whole cells and membranes.


Author(s):  
A. I. Musin ◽  
Yu. G. Borisova ◽  
G. Z. Raskil’dina ◽  
R. U. Rabaev ◽  
R. R. Daminev ◽  
...  

Objectives. This study aims to obtain alkenyl-gem-dichlorocyclopropanes from piperylene. The products are then subjected to thermocatalytic isomerization and hydrogenation.Methods. To determine the qualitative and quantitative composition of the reaction crudes, the following analytical methods were used: gas-liquid chromatography using the Crystal 2000 hardware complex, mass spectrometry using a Chromatec-Crystal 5000M device with the NIST 2012 database, and nuclear magnetic resonance (NMR) spectroscopy using a Bruker AM-500 device at operating frequencies of 500 and 125 MHz.Results. Alkenyl-gem-dichlorocyclopropanes were synthesized in the presence of triethylbenzyl ammonium chloride as catalyst. Their isomerization and hydrogenation gave the corresponding gem-dichlorocyclopentene and isomers of alkyl-gem-dichlorocyclopropanes. The structure of synthesized substances were analyzed by gas-liquid chromatography, mass spectrometry, and NMR spectroscopy.Conclusions. The results show that formation of four isomeric substituted gemdichlorocyclopropanes occurs in high yield during incomplete dichlorocyclopropanation of piperylene. The thermocatalytic isomerization of substituted gem-dichlorocyclopropanes in the presence of SAPO-34 zeolite leads to the formation of one product, i.e., gem-dichlorocyclopentene, and hydrogenation of substituted gem-dichlorocyclopropanes in the presence of Pd/C catalyst gives three isomeric alkyl-gem-dichlorocyclopropanes.


1986 ◽  
Vol 64 (9) ◽  
pp. 2088-2097 ◽  
Author(s):  
P. C. Cheng ◽  
R. I. Greyson ◽  
D. B. Walden

The cuticular membrane of the anther of Zea mays is ridged or rugose over most of its surface. The ridges arise during anther development and are confined to the cuticular membrane itself with no coincident folding of the cell wall, although some fibrous wall-like material becomes incorporated within the ridges. The height of a ridge, on mature anthers, is about 0.5 μm and although ridges are aligned, for the most part, in the long axis of the organ, ridges are continuous across cell boundaries in all directions. From transmission electron microscope views we conclude that the cuticle is homogeneous with a thickness of approximately 100 nm. The cuticular layer can be removed from the underlying wall by ZnCl2–HCl hydrolysis. Older anthers yield intact cuticles with persistent ridges. The ridges are not retained by cuticles from young anthers. Chloroform or hexane extraction removes about 30% of the dry weight from isolated cuticles. Characterization of the extract by gas–liquid chromatography – mass spectrometry reveals it is mainly composed of a mixture of odd- and even-numbered straight-chain, saturated hydrocarbons (C25 to C34).


1984 ◽  
Vol 30 (2) ◽  
pp. 188-191 ◽  
Author(s):  
S Yoshioka ◽  
S Saitoh ◽  
S Seki ◽  
K Seki

Abstract Six non-glucose polyols--mannose, fructose, 1-deoxyglucose, mannitol, glucitol, and inositol--were identified and evaluated in human serum and cerebrospinal fluid by gas-liquid chromatography and by gas-liquid chromatography/mass spectrometry. Concentrations of fructose, mannose, and inositol in the serum of healthy persons or children without metabolic diseases varied with age, as already reported for 1-deoxyglucose. Fructose, inositol, and glucitol concentrations in cerebrospinal fluid significantly exceeded those in serum. The method described here for determining polyols and for evaluating polyol patterns in serum, as well as the resulting data on children and healthy subjects, should be useful in investigations of the clinical and physiological significance of polyols.


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