Exudation, analysis

Phillips, G.O. Williams, P.A. (2001). Tree exudate gums natural and versatile food additives and ingredients. Food Ingredients and Analysis International, Vol.23, (nd),pp. 26- 28, ISSN 0968-574X. 

T. W. M. Fan, A. N. Lane, D. Crowley, and R. M. Higa.shi, Comprehensive analysis of organic ligands in whole root exudates using nuclear magnetic resonance and gas chromatography-mass spectro.scopy. Anal. Biochem. 257 57 (1997). 

Exudate collection in trap solutions usually requires subsequent concentration steps (vacuum evaporation, lyophilization) due to the low concentration of exudate compounds. Depending on the composition of the trap solution, the reduction of sample volume can lead to high salt concentrations, which may interfere with subsequent analysis or may even cause irreversible precipitation of certain exudate compounds (e.g., Ca-citrate, Ca-oxalate, proteins). Therefore, if possible, removal of interfering salts by use of ion exchange resins prior to sample concentration is recommended. Alternatively, solid-phase extraction techniques may be employed for enrichment of exudate compounds from the diluted trap solution (11,22). High-molecular-weight compounds may be concentrated by precipitation with organic solvents [methanol, ethanol, acetone 80% (v/v) for polysaccharides and proteins] or acidification [trichloroacetic acid 10% (w/v), per-... 

A detailed analysis of the root exudate of Phaseolus vulgaris found six flavonoids daidzein, coumestrol, naringenin, genistein, liquiritigenin, and isoli-... 

Table 1 Effect of Iron Stress on Chemical Composition of Root Exudates Collected from Barley Plants, as Determined by Combined NMR and GC-MS Analysis (Fan et al., 1997)...

Figure 9 A sensitivity analysis for exudation losses by maize roots. The sensitivity was analyzed by halving and doubling each parameter value in turn while keeping all other parameters at their standard values. Parameters shown on the graph are defined in the text. (From Ref. 55.)...

Variance in root size of 5-day old plants was not taken into account in either the calculation of pmol/root or pmold exuded/root. The weight of filtered and lyophilized exudate of 375 plants was used to extrapolate to the figure of 3245 individuals used for exudate collection in the analysis of exudation/root. 

These lightweight mixes were found necessary to provide adequate drainage. Chemical analysis of the root exudates was simplified by use of those relatively inert compounds. 

Two weeks after planting in the pipes, the plants were thinned to 35 pipe per pipe each and the cups to one plant each, and the treatments begun. Each first, third and fifth day of the week for twelve weeks the pipes were flushed with three liters of tap water poured in the elbow end. The water flowed past the plant root systems and drained out the screened end of the pipes into a flask. One hundred milliliter aliquots of this water ( root exudate ) were used to water the soybean plants in the cups three times weekly. After each flushing, two liters of a low nitrogen (50 ppm N) complete nutrient solution (Peter s Hydro-sol ) were added to each pipe. The soybean plants in cups were watered as needed at other times with tap water. On alternate weeks the soybean plants were fertilized with the complete nutrient solution. At 4, 8 and 12 weeks after the root exudate treatments started eighty soybean plants (10 treatments x 2 soybean varieties x 4 blocks) were randomly chosen for analysis. The soil was washed free of the plant roots and each soybean plant was divided into roots, nodules, stems, leaves and fruits. The plant parts were dried at 105°C for four days and weighed. 

Kerkvliet, N. and Oughton, J., Acute inflammatory response to sheep red blood cell challenge in mice treated with 2,3,7,8-tetrachlordibenzo-p-dioxin Phenotypic and functional analysis of peritoneal exudate cells, Toxicol. Appl. Pharmacol., 119, 248, 1993. 

Gartner S, Le Faucheur L, Roinel N, Paris-Pireyre N. Preliminary studies on the elemental composition of xylem exudate from two varieties of wheat by electron probe analysis. Scanning Electron Microsc 1984 IV 1739-1744. 

Miiller R, Morant M, Jarmer H, Nilsson L, Nielsen TH (2007) Genome-wide analysis of the ara-bidopsis leaf transcriptome reveals interaction of phosphate and sugar metabolism. Plant Physiol 143 156-171. doi http //www.plantphysiol.org/cgi/content/abstract/143/l/156 Neumann G, Romheld V (1999) Root exudation of carboxylic acids and protons in phosphorus-deficient plants. Plant Soil 211 121-130... 

As the separation characteristics of liquid chromatographic and electrophoretic techniques markedly differ from each other, combined methods using the advantages of both procedures have been successfully used for the analysis of flavonoids. Thus, the use of CZE-UV, HPTLC-UV and GC-MS for the measurement of flavonoids in seeds and root exudates of Lotus pedunculatus has been reported. The rooting solution and seed exudate were passed through cellulose acetate filters to bind the flavonoids. After extraction,... 

Physical Form. Volatile liquid, colorless or yellow, which is a mixture of natural substances obtained ftom resinous exudates or resinous wood ftom living or dead coniferous trees, especially pine trees. The chemical composition can vary with the source and method of derivation, but a typical analysis of turpentine is a-pinene, 82.5% camphene, 8.7% (3-pinene, 2.1% unidentified natural turpenes, 6.8%. 

The fluid exuded from a fresh or acute wound generally exhibits high levels of various growth factors (as determined by bioassay or immunoassay analysis). In contrast, the concentration of... 

A summary of the pertinent results from exudation studies conducted at PicArsn was prepd by Stein (Ref 5). In one series of tests to induce exudation and to obtain exudate samples for analysis and examination of properties, a loaded unfuzed shell was placed in an inverted position over a tared dish and maintained for several hours at 160°F (71°C), until exudation stopped. Then die dish was reweighed and % of exudate calcd Refs 1) C.H. Brooks, PB Rept 22930(1945),... 

Besides the gravimetric density test which is conducted with unwrapped cartridges, and the exudation test which can be conducted either with unwrapped cartridges or with prepd samples, the following stability tests are recommended before proceeding with complete chemical analysis... 

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