MANOMETRIC STUDIES WITH RHIZOSPHERE AND NON-RHIZOSPHERE SOIL

1957 ◽  
Vol 3 (5) ◽  
pp. 673-678 ◽  
Author(s):  
H. Katznelson ◽  
J. W. Rouatt

Manometric studies were carried out on the metabolic activity of different rhizosphere and non-rhizosphere soils from the greenhouse and the field. Oxygen consumption was distinctly greater with the rhizosphere soils. On the addition of substrates such as casamino acids or a mixture of carbohydrates and organic acids, greater oxygen uptake again occurred with the rhizosphere soils and was particularly striking with the amino acids. Chromatographic studies of extracts of rhizosphere and non-rhizosphere soil incubated with casamino acids suggested that certain amino acids such as arginine, proline, and tyrosine may be preferentially utilized in the rhizosphere.

1994 ◽  
Vol 267 (5) ◽  
pp. E648-E655 ◽  
Author(s):  
T. Brundin ◽  
J. Wahren

The renal contribution to the amino acid-induced whole body thermogenesis was examined. Using indirect calorimetry and catheter techniques, pulmonary and renal oxygen uptake and blood flow, blood temperatures, and net renal exchange of amino acids, glucose and lactate were measured in eight healthy men before and during 3 h of intravenous infusion of 720 kJ of an amino acid solution. During the infusion, the pulmonary oxygen uptake increased from 252 +/- 12 to 310 +/- 8 ml/min, cardiac output increased from 5.9 +/- 0.3 to 6.8 +/- 0.3 l/min, and the arterial blood temperature increased from 36.34 +/- 0.04 to 36.68 +/- 0.07 degrees C. Renal oxygen consumption, heat production, blood flow, and net glucose exchange remained unchanged during the infusion. The net renal uptake of amino acid energy from the blood rose from 2 +/- 2 to 11 +/- 4 W. The total renal energy expenditure was 9-10 W throughout the study period. It is concluded that intravenous amino acid infusion greatly augments the uptake and utilization of amino acids in the kidneys but does not stimulate the renal oxygen consumption, heat production, blood flow, or glucose release.


1979 ◽  
Vol 57 (13) ◽  
pp. 1473-1477 ◽  
Author(s):  
U. G. Bokhari ◽  
D. C. Coleman ◽  
Amy Rubink

Root exudates may have important effects on microbial growth and nutrient cycling in many ecosystems. We examined exudation patterns of two dominant plants in the shortgrass prairie.Root exudates of mature blue grama plants contained greater amounts of carbohydrates than younger plants, whereas the latter exuded slightly more amino N than the older plants. Axenic seedlings exuded larger amounts of sugars than normal seedlings; however, there was no difference in the amounts of amino N exuded. Among the amino acids exuded by axenic seedlings the levels of proline, methionine, and glutamic acids were higher than those of the other amino acids. The rhizosphere soil of both blue grama and fringed sagewort had more soluble sugars than the nonrhizosphere soil while the latter had more nonsoluble sugars. Both soluble and nonsoluble amino N were in greater concentrations in the nonrhizosphere soil of blue grama and fringed sagewort than in the rhizosphere soil of the same species. Rhizosphere soil of the above two species contained more polyphenols than the nonrhizosphere soil. Trace amounts of terpenes were found only in the soil associated with fringed sagewort.


Parasitology ◽  
1958 ◽  
Vol 48 (1-2) ◽  
pp. 149-164 ◽  
Author(s):  
June P. Thurston

1. Standard conditions are described for preparing suspensions of washed Trypanosoma lewisi and T. equiperdum in modified Ringer–phosphate solution.2. Oxygen consumption was measured with differential manometers, using microflasks containing 2–5 × 107 trypanosomes in 0·9 ml. of reaction mixture. Measurements of oxygen uptake were carried out at 37° C.3. T. lewisi respired slowly in the absence of substrate for up to 2 hr. The trypanosomes suffered little damage when stored at 5° C. for 24 hr. without substrate. No oxygen uptake was observed with T. equiperdum in the absence of substrate. The trypanosomes were viable after 24 hr. at 5° C. with glucose or glycerol as substrate, but not in the absence of substrate.4. With glucose as substrate, the rate of oxygen consumption by T. lewisi increased with the age of infection. This change was more marked with glutamine as substrate.5. With glucosamine as substrate, the oxygen uptake of T. lewisi was at a slightly lower rate than with glucose. The rate of oxygen uptake was still lower with Na l-glutamic acid, asparagine, aspartic acid, casein hydrolysate, yeast extract and Difco Bacto-peptone. Thirteen other amino-acids had no effect on the motility of the trypanosomes.6. With glycerol as substrate, the oxygen uptake of T. equiperdum was at a slightly lower rate than with glucose. The rate of oxygen uptake was very low with yeast extract, casein hydrolysate and Difco Bacto-peptone. No oxygen uptake or motility was recorded with glutamine, Na l-glutamic acid, glucosamine, asparagine, aspartic acid, dl-alanine, or Na acetate. Thirteen other amino-acids had no effect on the motility of the trypanosomes.7. Ammonia was liberated from glutamine by adult and reproductive phase T. lewisi.


Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 248
Author(s):  
Chang Ha Park ◽  
Hyeon Ji Yeo ◽  
Ye Jin Kim ◽  
Bao Van Nguyen ◽  
Ye Eun Park ◽  
...  

This study aimed to elucidate the variations in primary and secondary metabolites during Lycorisradiata flower development using high performance liquid chromatography (HPLC) and gas chromatography time-of-flight mass spectrometry (GC-TOFMS). The result showed that seven carotenoids, seven phenolic acids, three anthocyanins, and galantamine were identified in the L. radiata flowers. Most secondary metabolite levels gradually decreased according to the flower developmental stages. A total of 51 metabolites, including amines, sugars, sugar intermediates, sugar alcohols, amino acids, organic acids, phenolic acids, and tricarboxylic acid (TCA) cycle intermediates, were identified and quantified using GC-TOFMS. Among the hydrophilic compounds, most amino acids increased during flower development; in contrast, TCA cycle intermediates and sugars decreased. In particular, glutamine, asparagine, glutamic acid, and aspartic acid, which represent the main inter- and intracellular nitrogen carriers, were positively correlated with the other amino acids and were negatively correlated with the TCA cycle intermediates. Furthermore, quantitation data of the 51 hydrophilic compounds were subjected to partial least-squares discriminant analyses (PLS-DA) to assess significant differences in the metabolites of L. radiata flowers from stages 1 to 4. Therefore, this study will serve as the foundation for a biochemical approach to understand both primary and secondary metabolism in L. radiata flower development.


Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1377
Author(s):  
Song-Hui Soung ◽  
Sunmin Lee ◽  
Seung-Hwa Lee ◽  
Hae-Jin Kim ◽  
Na-Rae Lee ◽  
...  

Numerous varieties of doenjang are manufactured by many food companies using different ingredients and fermentation processes, and thus, the qualities such as taste and flavor are very different. Therefore, in this study, we compared many products, specifically, 19 traditional doenjang (TD) and 17 industrial doenjang (ID). Subsequently, we performed non-targeted metabolite profiling, and multivariate statistical analysis to discover distinct metabolites in two types of doenjang. Amino acids, organic acids, isoflavone aglycones, non-DDMP (2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4- one) soyasaponins, hydroxyisoflavones, and biogenic amines were relatively abundant in TD. On the contrary, contents of dipeptides, lysophospholipids, isoflavone glucosides and DDMP-conjugated soyasaponin, precursors of the above-mentioned metabolites, were comparatively higher in ID. We also observed relatively higher antioxidant, protease, and β-glucosidase activities in TD. Our results may provide valuable information on doenjang to consumers and manufacturers, which can be used while selecting and developing new products.


1988 ◽  
Vol 15 (4) ◽  
pp. 557 ◽  
Author(s):  
MJ Canny ◽  
ME Mccully

Three methods of sampling xylem sap of maize roots were compared: sap bleeding from the stem cut just above the ground; sap bleeding from the cut tops of roots still undisturbed in the ground; and sap aspirated from excavated roots under reduced pressure. The bleeding saps were often unobtainable. When their composition was measured with time from cutting, the concentrations of the major solutes approximately doubled in 2 h. Aspirated sap was chosen as the most reliable sample of root xylem contents. Solute concentrations of the saps showed great variability between individual roots for all solutes, but on average the concentrations found (in �mol g-1 sap) were: total amino acids, 1.8; nitrate, 1.8; sugars (mainly sucrose), 5.4; total organic acids, 18.3. Individual amino acids also varied greatly between roots. Glutamine, aspartic acid and serine were generally most abundant. The principal organic acid found was malic, approximately 8 �mol g-1. From these analyses the ratios of carbon in the fractions (sugars : amino acids : organic acids) = (44 : 6 : 50). 14Carbon pulse fed to a leaf appeared in the root sap within 30 min, rose to a peak at 4-6 h, and declined slowly over a week. During all this time the neutral, cation and anion fractions were sensibly constant in the proportions 86 : 10 : 4. The 14C therefore did not move towards the equilibrium of 12C-compounds in the sap. It is argued that the results do not support a hypothesis of formation of amino carbon from recent assimilate and reduced nitrate in the roots and an export of this to the shoot in the transpiration stream.


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