Free amino acid concentrations in red pine needles during three successive autumns

1988 ◽  
Vol 18 (10) ◽  
pp. 1286-1290 ◽  
Author(s):  
Y. T. Kim ◽  
C. Glerum

Seasonal free amino acid concentrations in current-year red pine (Pinusresinosa Ait.) needles were determined weekly or biweekly from September to December over a 3-year period. Tryptophan and histidine were the only amino acids that had significant positive trends, increasing in concentration between September and December in all 3 years, while threonine had a significant negative trend, decreasing in concentration in all 3 years. The positive tryptophan trend was the most consistent.

1987 ◽  
Vol 17 (1) ◽  
pp. 27-30 ◽  
Author(s):  
Y. T. Kim ◽  
C. Glerum ◽  
J. Stoddart ◽  
S. J. Colombo

Greenhouse-grown black spruce and jack pine container seedlings were fertilized weekly with a 20–8–20 fertilizer at four concentrations during the fall. Seedlings were sampled when 23 weeks old towards the end of the greenhouse cultural period to determine the effect of fertilization on the free amino acid concentrations. All amino acids, except tryptophan, showed significant increases in concentration with higher levels of fertilizer; the concentration of tryptophan decreased with increasing fertilizer concentration. Amino acids with the highest concentrations in black spruce were arginine, glutamic acid, and proline, while in jack pine, besides these three, aspartic acid and glutamine were also found in high concentrations. Black spruce had significantly higher amino acid concentrations than jack pine. The concentrations of certain free amino acids may be more sensitive indicators of seedling nitrogen status than total foliar nitrogen.


1973 ◽  
Vol 59 (1) ◽  
pp. 57-63 ◽  
Author(s):  
W. DE LOECKER ◽  
M. L. STAS

SUMMARY Changes in the concentrations of free amino acids in intracellular fluids and blood plasma were measured in rats treated with cortisol. Increasing age raised the concentrations of free amino acids in plasma, while in liver, with the exception of glycine and alanine, decreased concentrations were observed. Cortisol treatment reduced free amino acid levels in plasma and liver which suggested a progressive catabolism of body proteins and increased protein synthesis in the liver. In skeletal muscle of control rats the free amino acid concentrations increased during the experimental period. Cortisol increased the concentration of certain amino acids and decreased that of others due to an increased protein turnover in muscle.


1991 ◽  
Vol 71 (3) ◽  
pp. 953-957 ◽  
Author(s):  
G. W. Sedgwick ◽  
T. W. Fenton ◽  
J. R. Thompson

The effect of the protein precipitants acetone, acetonitrile, perchloric acid and trichloroacetic acid on free amino acid concentrations in supernatants from ovine plasma and bovine serum albumin solutions was determined. The organic precipitants decreased (P < 0.05) free amino acid concentrations in a protein concentration dependent manner while the acid precipitants had no effect. Key words: Amino acids, protein precipitating agents


1974 ◽  
Vol 61 (2) ◽  
pp. 463-472
Author(s):  
P. D. EVANS ◽  
A. C. CROSSLEY

Free amino acid concentrations have been measured in haemolymph samples taken from 3rd instar larvae of the blowfly, Calliphora vicina, at various stages prior to pupariation. The amino acids found in the haemocyte fraction only accounted for 6% of the total free amino acid concentration of the haemolymph. However, a high percentage of the dicarboxylic amino acids, glutamate and aspartate, 62% and 69% respectively, appeared to be sequestered in the haemocyte fraction at 72 h prior to pupariation. The percentage of the other individual amino acids found in the haemocyte fraction represented less than 10% of their amount in whole haemolymph. It is proposed that these results, together with the increase in the haemocyte levels of glutamate observed after injecting larvae with saline containing glutamate, are one of the first indications of a homeostatic function of insect haemocytes with respect to haemolypmh amino acids.


1986 ◽  
Vol 13 (3) ◽  
pp. 343 ◽  
Author(s):  
CPL Grof ◽  
M Johnston ◽  
PF Brownell

Consistent changes in the free amino acid concentrations in response to sodium nutrition were observed in mature leaves of the C4 species Amaranthus tricolor and Chloris gayana. The amino acids alanine, γ-aminobutyric acid and glycine were present in greater and aspartate and arginine in lower concentrations in mature leaves of sodium-deficient than in normal plants of both species.


1976 ◽  
Vol 54 (11) ◽  
pp. 1927-1931 ◽  
Author(s):  
J. Alison Hanson ◽  
Thomas H. Dietz

Free amino acids constitute 11% of the cellular solute in Ligumia subrostrata acclimated in pond water but less than 1% of blood total solute. Arginine, glutamate, histidine, and alanine account for 60% of the cellular free amino acid concentration. Tissue free amino acid concentrations increase when the animals are exposed to dehydration and anoxic stress. Free amino acids contributing most to the elevated tissue amino acid concentrations are glutamate, alanine, threonine, and serine. These specific free amino acids play an important role in cellular volume regulation.


1994 ◽  
Vol 86 (6) ◽  
pp. 653-662 ◽  
Author(s):  
BO Ahlman ◽  
Kerstin Andersson ◽  
Carl-Eric Leijonmarck ◽  
Olle Ljungqvist ◽  
Lennart Hedenborg ◽  
...  

1. The effects of short-term starvation and refeeding on the free amino acid concentrations of the intestinal mucosa were characterized in male subjects (n = 6), using endoscopically obtained biopsy specimens from the duodenum and from all four segments of the colon. 2. The alterations in the amino acid concentrations in response to short-term starvation were overall uniform in both duodenal and colonic mucosa as well as in plasma. Most amino acids decreased, whereas branched-chain amino acids increased. 3. In the colon, glutamic acid and glutamine decreased during the starvation period, whereas they remained unaltered in the duodenum. This was the major difference in response to short-term starvation between the amino acid concentrations in the intestinal mucosa of the duodenum and colon. 4. Refeeding for 3 days normalized the amino acid concentrations except for glutamic acid, asparagine and histidine, which remained low in the colon, and threonine, which showed an overshoot in both parts of the intestine. 5. The changes in mucosal amino acid concentrations seen in response to starvation and refeeding were uniform in the four segments of the colon. This suggests that sampling from the rectum/sigmoid colon will give representative values for the free amino acid concentrations of the entire large intestine.


2020 ◽  
Vol 22 (9) ◽  
pp. 657-662 ◽  
Author(s):  
Mustafa Celik ◽  
Alper Şen ◽  
İsmail Koyuncu ◽  
Ataman Gönel

Aim and Objective:: To determine the mechanisms present in the etiopathogenesis of nasal polyposis. It is not clear whether amino acids contribute in a causal way to the development of the disease. Therefore, the aim of this study was to determine the plasma-free amino acid profile in patients with nasal polyposis and to compare the results with a healthy control group. Materials and Methods:: This was a prospective controlled study that took place in the Otolaryngology Department at the Harran University Faculty of Medicine between April 2017 and April 2018. Plasmafree amino acid profile levels were studied in serum samples taken from a patient group and a healthy control group. Patients who were diagnosed with bilateral diffuse nasal polyposis and were scheduled for surgical interventions were included in this study. Individuals whose age, gender, and body mass index values were compatible with that of the patient group and who did not have any health problems were included in the control group. All the participants whose levels of plasma-free amino acid were thought to be affected by one or more of the following factors were excluded from the study: smoking and alcohol use, allergic rhinitis presence, the presence of acute or chronic sinusitis, a history of endoscopic sinus surgery, unilateral nasal masses, a history of chronic drug use, systemic or topical steroid use in the last three months for any reason, and liver, kidney, hematological, cardiovascular, metabolic, neurological, or psychiatric disorders or malignancies. Results: In patients with nasal polyposis, 3-methyl histidine (3-MHIS: nasal polyposis group (ng) = 3.22 (1.92 – 6.07); control group (cg) = 1.21 (0.77 – 1.68); p = 0.001); arginine (arg: ng = 98.95 (70.81 – 117.75); cg = 75.10 (54.49 – 79.88); p = 0.005); asparagine (asn: ng = 79.84 (57.50 – 101.44); cg = 60.66 (46.39 – 74.62); p = 0.021); citrulline (cit: ng = 51.83 (43.81 – 59.78); cg = 38.33 (27.81 – 53.73); p = 0.038); cystine (cys: ng = 4.29 (2.43 – 6.66); cg = 2.41 (1.51 – 4.16); p = 0.019); glutamic acid (glu: ng = 234.86 (128.75 – 286.66); cg = 152.37 (122.51 – 188.34); p = 0.045); histidine (his: ng = 94.19 (79.34 – 113.99); cg = 74.80 (62.76 – 98.91); p = 0.018); lysine (lys: ng = 297.22 (206.55 – 371.25); cg = 179.50 (151.58 – 238.02); p = 0.001); ornithine (ng = 160.62 (128.36 – 189.32); cg = 115.91 (97.03 – 159.91); p = 0.019); serine (ser: ng = 195.15 (151.58 – 253.07); cg = 83.07 (67.44 – 92.44); p = 0.001); taurine (tau: ng = 74.69 (47.00 – 112.13); cg = 53.14 (33.57 – 67.31); p = 0.006); tryptophan (trp: ng = 52.31 (33.81 – 80.11); cg = 34.44 (25.94 – 43.07); p = 0.005), homocitrulline (ng = 1.75 (1.27 – 2.59); cg = 0.00 (0.00 – 0.53); p = 0.001); norvaline (ng = 6.90 (5.61 – 9.18); cg = 4.93 (3.74 – 7.13); p = 0.021); argininosuccinic acid (ng = 14.33 (10.06 – 25.65); cg = 12.22 (5.77 – 16.87) p = 0.046); and plasma concentrations were significantly higher than in the healthy control group (p <0.05). However, the gamma-aminobutyric acid (gaba: ng = 0.16 (0.10 – 0.24); cg = 0.21 (0.19 – 0.29); p = 0.010) plasma concentration was significantly lower in the nasal polyposis group than in the healthy control group. Conclusion: In this study, plasma levels of 15 free amino acids were significantly higher in the nasal polyposis group than in the healthy control group. A plasma level of 1 free amino acid was found to be significantly lower in the nasal polyposis group compared to the healthy control group. Therefore, it is important to determine the possibility of using the information obtained to prevent the recurrence of the condition and to develop effective treatment strategies. This study may be a milestone for studies of this subject. However, this study needs to be confirmed by further studies conducted in a larger series.


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