scholarly journals Amino acids in Arctic aerosols

2012 ◽  
Vol 12 (7) ◽  
pp. 17367-17396 ◽  
Author(s):  
E. Scalabrin ◽  
R. Zangrando ◽  
E. Barbaro ◽  
N. M. Kehrwald ◽  
J. Gabrieli ◽  
...  

Abstract. Amino acids are significant components of atmospheric aerosols, affecting organic nitrogen input to marine ecosystems, atmospheric radiation balance, and the global water cycle. The wide range of amino acid reactivities suggest that amino acids may serve as markers of atmospheric transport and deposition of particles. Despite this potential, few measurements have been conducted in remote areas to assess amino acid concentrations and potential sources. Polar regions offer a unique opportunity to investigate atmospheric processes and to conduct source apportionment studies of such compounds. In order to better understand the importance of amino acid compounds in the global atmosphere, we determined free amino acids (FAAs) in seventeen size-segregated aerosol samples collected in a polar station in the Svalbard Islands from 19 April until 14 September 2010. We used an HPLC coupled with a tandem mass spectrometer (ESI-MS/MS) to analyze 20 amino acids to quantify compounds at fmol m−3 levels. Mean total FAA concentration was 1070 fmol m−3 where serine and glycine were the most abundant compounds in almost all samples and accounted for 45–60% of the total amino acid relative abundance. The other eighteen compounds had average concentrations between 0.3 and 98 fmol m−3. The higher amino acid concentrations were present in the ultrafine aerosol fraction (<0.49 μm) and accounted for the majority of the total amino acid content. Local marine sources dominate the boreal summer amino acid concentrations, with the exception of the regional input from Icelandic volcanics.

2012 ◽  
Vol 12 (21) ◽  
pp. 10453-10463 ◽  
Author(s):  
E. Scalabrin ◽  
R. Zangrando ◽  
E. Barbaro ◽  
N. M. Kehrwald ◽  
J. Gabrieli ◽  
...  

Abstract. Amino acids are significant components of atmospheric aerosols, affecting organic nitrogen input to marine ecosystems, atmospheric radiation balance, and the global water cycle. The wide range of amino acid reactivities suggest that amino acids may serve as markers of atmospheric transport and deposition of particles. Despite this potential, few measurements have been conducted in remote areas to assess amino acid concentrations and potential sources. Polar regions offer a unique opportunity to investigate atmospheric processes and to conduct source apportionment studies of such compounds. In order to better understand the importance of amino acid compounds in the global atmosphere, we determined free amino acids (FAAs) in seventeen size-segregated aerosol samples collected in a polar station in the Svalbard Islands from 19 April until 14 September 2010. We used an HPLC coupled with a tandem mass spectrometer (ESI-MS/MS) to analyze 20 amino acids and quantify compounds at fmol m−3 levels. Mean total FAA concentration was 1070 fmol m−3 where serine and glycine were the most abundant compounds in almost all samples and accounted for 45–60% of the total amino acid relative abundance. The other eighteen compounds had average concentrations between 0.3 and 98 fmol m−3. The higher amino acid concentrations were present in the ultrafine aerosol fraction (< 0.49 μm) and accounted for the majority of the total amino acid content. Local marine sources dominate the boreal summer amino acid concentrations, with the exception of the regional input from Icelandic volcanic emissions.


Author(s):  
Lata . ◽  
Narender Singh Atri

Objective: In this paper amino acid profile of Lentinus sajor-caju (Fr.) Fr., a basidiomycetous mushroom has been investigated.Methods: During the evaluation 15 amino acids (lysine, aspartic acid, serine, threonine, glutamic acid, cysteine, glycine, alanine, valine, methionine, isoleucine, leucine, tyrosine, phenylalanine and histidine) were determined from the dried sample of Lentinus sajor-caju by following the standard technique of biochemistry using ion-exchange chromatography.Results: The total amino acid content has been evaluated at 18.82 g/100g. Amongst the evaluated amino acids, exogenous amino acid lysine (6.66 g/100g) is preponderantly present in comparison to all other amino acids. The essential amino acid (EAA) index (44.64%) and biological value (BV=36.93%) has also been determined for the examined sample.Conclusion: Lentinus sajor-caju (Fr.) Fr. is a potential source of quality protein with a substantial proportion of exogenous and endogenous amino acids.


1996 ◽  
Vol 76 (2) ◽  
pp. 163-169 ◽  
Author(s):  
R. J. Boila ◽  
S. C. Stothers ◽  
L. D. Campbell

The concentrations of protein and individual amino acids were determined in the grain from three cultivars of wheat and three cultivars of barley, each grown at 12 locations throughout Manitoba over 3 consecutive years. Protein concentration differed (P < 0.05) among the cultivars of wheat but not (P > 0.05) among cultivars of barley. Although the concentrations of several amino acids differed (P < 0.05) among cultivars of wheat or barley the differences among cultivars of each grain were not considered to be critical in relation to the requirements for indispensable amino acids for swine or poultry. The percentage of an ammo acid in the DM of wheat and barley increased (P < 0.05) linearly with an increase in percentage of protein in the grain. The wide range of r2 (0.29 to 0.88) obtained for this amino acid-protein relationship may be due to the different effect of environment (location and year of growth) on the concentration of individual amino acids, compared to protein, among cultivars of wheat or barley. The percentage of total variance due to an interaction between cultivar and environment was low for protein but was several fold higher for individual amino acids. The error in the prediction of amino acid concentrations with regression equations may be no different than the error associated with predicting the mean concentrations of amino acids in the protein of wheat or barley as g (100 g protein)−1, and obtained from tabulations of analyses. However, regression equations for lysine in wheat and barley did account for the significant (P < 0.05) decrease in concentration of lysine in the protein as the percentage of protein in these grains increased. Key words: Grain, wheat, barley, protein, amino acids, Manitoba


1977 ◽  
Vol 166 (1) ◽  
pp. 49-55 ◽  
Author(s):  
A Palou ◽  
L Arola ◽  
M Alemany

Plasma amino acid concentrations were determined in virgin female rats, in pregnant rats (12 and 21 days after impregnation) and in 21-day foetuses. The total amino acid concentration in plasma decreases significantly with pregnancy, being lower at 12 than at 21 days. Alanine, glutamine+glutamate and other ‘gluconeogenic’ amino acids decrease dramatically by mid-term, but regain their original concentrations at the end of the pregnancy. With most other amino acids, mainly the essential ones, the trend is towards lower concentrations which are maintained throughout pregnancy. These data agree with known nitrogen-conservation schemes in pregnancy and with the important demands on amino acids provoked by foetal growth. In the 21-day foetuses, concentrations of individual amino acids are considerably higher than in their mothers, with high plasma foetal/maternal concentration ratios, especially for lysine, phenylalanine and hydroxy-proline, suggesting active protein biosynthesis and turnover. All other amino acids also have high concentration ratios, presumably owing to their requirement by the foetuses for growth. Alanine, glutamine+glutamate, asparagine+aspartate, glycine, serine and threonine form a lower proportion of the total amino acids in foetuses than in the virgin controls or pregnant rats, probably owing to their role primarily in energy metabolism in the adults. The results indicate that at this phase of foetal growth, the placental amino acid uptake is considerable and seems to be higher than immediately before birth.


2004 ◽  
Vol 79 (2) ◽  
pp. 231-240 ◽  
Author(s):  
A. I. García ◽  
J. C. de Bias ◽  
R. Carabaño

AbstractTwenty-eight New Zealand White X Californian doe rabbits weighing 3791±141 g were surgically fitted with a glass T-cannula at ileum level. Animals were given ad libitum access to either a casein-based diet (C) or a protein-free diet (PF). The only difference in the ingredient composition of the diets was the substitution of 160g/kg of maize starch by casein in the C diet. Animals were randomly allotted to each experimental diet. Seven rabbits per diet were not allowed to practice caecotrophy. The C diet resulted in higher food dry matter (DM) intake (DMI) (111-5 v. 51-5 g/day), food nitrogen intake (3-12 v. 0-20 g/day), ileal flow of DM (56-0 v. 23-8 g/day) and ileal flow of nitrogen (0-72 v. 0-24 g/day) but lower soft faeces DMI (21-7 v. 41-4 g/day) than the PF diet. A linear relationship between ileal endogenous nitrogen flow and total DMI was found for animals given the C but not for the PF diet. The ingestion ofC diet led to a higher (proportionately 0-41, on average), endogenous ileal amino acid flow than PF diet for all amino acids except for glycine. The ileal flow of glycine was proportionately 0-25 higher in animals given the PF diet than in animals given the C diet. The C diet resulted in higher content of nitrogen, threonine and proline in soft faeces than the PF diet. In contrast, the ingestion of the PF diet led to a higher content of lysine and methionine in soft faeces than the C diet. Within the C diet, animals practising caecotrophy showed higher ileal flow of DM (73-4 v. 56-0 g/day) and phenylalanine (0-834 v. 0-677 g/kg DMI) than animals not practising it. Caecotrophy led to a higher endogenous proportion of some of the most important limiting essential amino acids in rabbits, such as arginine, lysine, phenylalanine and threonine. In rabbits, the use of PF diets has limited practical application in the estimation of nitrogen endogenous losses as the low food DMI and the high soft faecesDMI leads to abnormal food: soft faeces intake ratio. Moreover, due to the important effect of caecotrophy on the amino acid composition of endogenous losses, it is important to correct the total amino acid content of the ileal chyme by the undigested amino acid residue coming from the soft faeces intake. This correction could be made, without the methodological complexity implied, by fitting animals with a wooden collar and thereby avoiding caecotrophy as in the present trial.


2019 ◽  
pp. 135-143
Author(s):  
Evgeniy Nikolaevich Sechin ◽  
Oleg Anatolyevich Marakaev ◽  
Gavriil Borisovich Gavrilov

Amino acid composition of aboveground and underground vegetative organs of Dactylorhiza maculata (L.) Soó (Orchidaceae), one of the representatives of the tuberoid species of orchids growing under the natural conditions of the center of European Russia, was detected using the method of zone capillary electrophoresis. The presence of 15 amino acids in the plant material, nine of them are «essential» (lysine, phenylalanine, histidine, leucine, isoleucine, methionine, valine, threonine, tryptophan) was established. The highest total amino acid content is characteristic of the leaves, the smallest for the old (wintered) caulorrhizous tuberoids. Among the identified amino acids in the plant material of D. maculata, the maximum total content is of leucine, the minimum are of tryptophan and methionine. The vegetative organs are also rich in alanine, arginine, valine and phenylalanine. The total content of amino acids in young caulorrhizous tuberoids is 38% higher than that in old storage organs. These differences are most pronounced for arginine, which is probably due to the spare function of this amino acid, containing more than 30% nitrogen. The got data indicate the promise of further studies of the amino acid composition of D. maculata and can characterize this species as a source of medicinal valuable substances with a broad spectrum of pharmacological activity.


2021 ◽  
Vol 9 ◽  
pp. 3-33
Author(s):  
V. I. Silaev ◽  
◽  
A. V. Kokin ◽  
N. V. Pavlovich ◽  
S. N. Shanina ◽  
...  

We studied 14 samples of gram-negative and gram-positive bacteria, unicellular yeasts and green algae using optical, atomic force and analytical scanning electron microscopy, thermal analysis, gas chromatography, infrared spectroscopy, inductively coupled plasma mass spectrometry and isotope mass spectrometry. In shape, the cells of microorganisms vary from rod-shaped to lenticular and coccoid, in size they range from mesonanometer to micrometer. A strong positive correlation was found between the extreme cell sizes. An admixture of inorganic chemical elements — Mg, Ca, Ba, Na, K, Cu, Zn, P, S, Cl and submicron-sized precipitates of mineral phases — carbonates, phosphate sulfates, hydrogen sulfate phosphates, hydrogen phosphates, halite, kaolinite, was found in the chemical composition of the studied microorganisms, metal alloys of brass composition, baddeleyite. Among the 45 microelements identified in microorganisms, there were 7 essential elements (E), 17 physiogenically active (FA) and 19 abiotic (AB). The total concentration of trace elements ranged from 0.003—0.26 wt. %. The value of the essential coefficient — E / AB — averaged 196 ± 153. Microorganisms were characterized by a mixed fat-protein elemental composition, they contained 14 amino acids belonging to the aliphatic, aromatic, basic, acidic, hydroxyl, imino and sulfur-containing groups. The total amino acid content ranged from 409 to 942 (682 ± 221) mg/g. Up to half of the amino acids were represented by the left (L) and right (D) enantiomers. The degree of racemization (D / L) ranged from 0.01 to 0.37. Yeast and chlorella were characterized by the most isotopically heavy composition of carbon in combination with relatively isotopically light nitrogen. In bacteria, a statistically lighter carbon was found in combination with a much heavier nitrogen. According to a number of properties — the chemical composition of organic matter, microelements, the degree of enrichment with antibiotic elements, the content of amino acids and the degree of their racemization — gram-negative and gram-positive bacteria differed. In general, the studied biological microorganisms were fundamentally different from the abiogenic organic substances found in meteorites and products of modern volcanism regarding their elemental and amino acid composition, carbon and nitrogen isotopes.


2018 ◽  
Vol 54 (2C) ◽  
pp. 458
Author(s):  
Nguyen Thi Thanh Ngoc

Brewer’s yeast spent, obtained after the main fermentation stage, is a rich- in-protein source(protein content accounts for 48 - 50 % dry matter). In order to use efficiently this source, it washydrolysed by different methods. Protein hydrolysate products are normally mixtures of peptidesand amino acids. Protein hydrolysates have a wide range of applications in food. It can be usedas emulsifying agents in a number of applications such as salad dressings, spreads, ice cream,coffee whitener, cracker, and meat products like sausages. However, bitterness in hydrolysates isone of the major undesirable aspects for various applications in food processing. In this study,we used enzymatic mixture alcalase and flavourzyme, yeast treatment methods to hydrolysebrewer’s yeast. The hydrolysate and fractions of protein hydrolysate obtained after filtration with10 kDa and 3 kDa filters were used for determination of bitterness and hydrophobic amino acidscontent. The bitter taste of hydrolysate was determined by sensory method (using quininestandard) and amino acid content was analysed by HPLC method. The result showed the closerelationship between bitter taste and hydrophobic amino acid content. The bitter taste of proteinhydrolysate was reduced as the hydrophobic amino acid content decreased. When the bitter taste(equivalent to quinine concentration) decreased from 16.25 μmol/l to 3.59 μmol/l, the totalcontent of hydrophobic amino acids in protein hydrolysate reduced from 1653 μg/ml to 932μg/ml.


OENO One ◽  
1999 ◽  
Vol 33 (2) ◽  
pp. 49
Author(s):  
Corine Larchevêque ◽  
A. Casanova

<p style="text-align: justify;">Numerous studies have been carried out on the vine, must and wine, but few on sap. Main phenological stages i.e. bud burst, the flowering period, veraison and the ripening period have been well described. However, at the present time, no study is available identifying the main amino acids of the xylem sap, at the formentioned periods. Located within the « Graves de Pessac-Léognan » vineyard, the plot area studied has a clayey-chalky soil with a small amount of sand present. The cultivar Cabernet franc was grafted on the Fercal rootstock. Planted in June 1982, the vine was trained with Guyot pruning and no tillage. The density of the plantation was 5.550 vines per ha. Four rows of 21 vines were sampled.</p><p style="text-align: justify;">Analysis of xylem sap, by H.P.L.C., at the four stages, taken from several vintages, showed that the global content of amino acids varied year to year (LARCHEVÊQUE, 1998). The experiment reported on herein was carried out in order to determine both the main amino acids in the xylem sap and to identify a marker amongst them, having the same evolution as that of the global amino acid content from one phenological stage to the next. A pool of eight amino acids, all present in large quantities (about 80 p. cent of total amino acid content), was always noted : asparagine/glutamine, tyrosine, arginine, aspartic acid, glutamic acid, histidine and proline. Concentration levels of these components differed in sap, depending on the vintage, at the same phenological stage. At bud burst, as at the flowering period, the sap had a similar qualitative composition.</p><p style="text-align: justify;">It was noteworthy that aspartic acid evidenced the same evolution that of the total amino acid content (i.e. the same variation in percentage) from one phenological stage to the next. Aspartic acid should therefore be regarded as a « marker » of total amino acid content evolution during the vegetative cycle.</p>


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