Helix-coil stability constants for the naturally occurring amino acids in water. XIII. The presence of by-products in amino-acid analysis of copolymers and their effect on the guest parameters; recomputed values of σ ands forL-serine

Biopolymers ◽  
1977 ◽  
Vol 16 (7) ◽  
pp. 1587-1592 ◽  
Author(s):  
J. W. Van Nispen ◽  
D. J. Hill ◽  
H. A. Scheraga
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Stability Constants ◽  
Amino Acid Analysis ◽  
Naturally Occurring ◽  
By Products

scholarly journals Amino acid analysis at the picomole level. Application to the C-terminal sequence analysis of polypeptides

1981 ◽  
Vol 199 (3) ◽  
pp. 547-555 ◽  
Author(s):  
J Y Chang ◽  
R Knecht ◽  
D G Braun
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Analysis ◽  
Protein Hydrolysate ◽  
Visible Region ◽  
Reversed Phase ◽  
Terminal Sequence ◽  
Naturally Occurring ◽  
Ion Exchange Separation ◽  
Buffer Mixture

Amino acids labelled with dimethylaminoazobenzenesulphonyl chloride can be separated by reversed-phase high-pressure liquid chromatography and detected in the visible region (436 nm). All 19 naturally occurring amino acids can be separated on a Zorbax ODS column by employing two different gradient systems consisting of an acetonitrile/aqueous buffer mixture. As little as 2--5 pmol of an individual dimethylaminoazobenzenesulphonyl-amino acid can be quantitatively analysed with reliability, and only 10--30 ng of the dimethylaminoazobenzenesulphonylated protein hydrolysate is needed for each complete amino acid analysis. This new technique is as sensitive as any of the current amino acid analysis methods involving ion-exchange separation plus fluorescence detection, and is technically much simpler. By the combination of this sensitive amino acid-analysing technique with carboxypeptidase, we have been able to determine the C-terminal sequence of polypeptides at the picomole level.

scholarly journals Regulation of rat magnocellular neurosecretory system by D-aspartate: evidence for biological role(s) of a naturally occurring free D-amino acid in mammals

2000 ◽  
Vol 167 (2) ◽  
pp. 247-252 ◽  
Author(s):  
H Wang ◽  
H Wolosker ◽  
J Pevsner ◽  
SH Snyder ◽  
DJ Selkoe
Keyword(s):  
Gene Expression ◽  
Amino Acids ◽  
Amino Acid ◽  
Physiological Function ◽  
Neurosecretory System ◽  
Milk Ejection ◽  
Magnocellular Neurons ◽  
Rat Hypothalamus ◽  
Naturally Occurring

Little evidence is available for the physiological function of D-amino acids in species other than bacteria. Here we demonstrate that naturally occurring freed -aspartate (D-Asp) is present in all magnocellular neurons of rat hypothalamus. The levels of this naturally occurring D-amino acid were elevated during lactation and returned to normal thereafter in the magnocellular neurosecretory system, which produces oxytocin, a hormone responsible for milk ejection during lactation. Intraperitoneal injections of D-Asp reproducibly increased oxytocin gene expression and decreased the concentration of circulating oxytocin in vivo. Similar changes were observed in the vasopressin system. These results provide evidence for the role(s) of naturally occurring free D-Asp in mammalian physiology. The findings argue against the conventional concept that only L-stereoisomers of amino acids are functional in higher species.

Effects of some Amino-acid and Purine Antagonists on Chick Embryos

Development ◽  
1958 ◽  
Vol 6 (2) ◽  
pp. 365-372
Author(s):  
C. H. Waddington ◽  
Margaret Perry
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Effective Concentration ◽  
Metabolic Inhibitors ◽  
Chick Embryos ◽  
Purine Analogue ◽  
Know How ◽  
Naturally Occurring ◽  
Different Types ◽  
Strong Action

Several authors have studied the effects on developing embryos of substances which are analogues of naturally occurring amino-acids and purines, and known to act, in other systems, as metabolic inhibitors. It was emphasized by Waddington, Feldman, & Perry (1955) that any particular substance may exhibit very different effects in embryos of different types. They found, for instance, that the purine analogue 8-azaguanine has a very strong action in the chick and a much lesser one in the newt embryo. It is therefore necessary to consider the various classes of embryos separately. In this communication we shall be concerned only with chick embryos. Substances under test can be administered to such embryos by injection through the shell, as was done in the paper cited above With this technique it is impossible to know how much diffusion takes place of the substance injected, and one cannot therefore be certain of the effective concentration which actually reaches the embryo.

DESIGNING BALANCED FEEDS FOR INDUSTRIAL AQUACULTURE USING PROTEIN HYDROLYSATES OF FISH BY-PASS RAW MATERIALS

Fisheries ◽  
2021 ◽  
Vol 2021 (4) ◽  
pp. 81-88
Author(s):  
Olga Mezenova ◽  
Dmitriy Pyanov ◽  
Svetlana Agafonova ◽  
Natalia Mezenova ◽  
V. Volkov
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Amino Acid ◽  
Raw Materials ◽  
Protein Hydrolysates ◽  
Total Protein Content ◽  
Alternative Sources ◽  
Amino Acid Balance ◽  
Limiting Amino Acids ◽  
By Products

The perspective of the production of domestic compound feed for the development of industrial aquaculture in Russia is shown. Alternative sources of protein in mixed fodder for salmon and sturgeon have been investigated. The advantages of using protein hydrolysates instead of a part of fishmeal in compound feed are described. The advantages of protein hydrolysates from fish by-products are considered, the chemical composition and molecular fractional composition of sublimated protein hydrolysates obtained by enzymatic and thermal pathways from sardinella scales and ridges are studied. The presence in hydrolysates of 53.3 - 97.7% of low molecular weight peptides with a molecular weight of less than 10 kDa with a total protein content of 80.8-94.1% was established. Indicators of amino acid balance (scor) of hydrolyzates of scales and ridges of sardinella were calculated in relation to the established requirements for amino acids in salmonids. Indicators of amino acid balance (scor) of hydrolyzates of scales and ridges of sardinella were calculated in relation to the established requirements for amino acids in salmonids.It was found that the introduction of an enzymatically obtained hydrolyzate is more favorable for an increase in the content of limiting amino acids in mixed feed, and the use of sardinella scales for hydrolysis is more preferable than its ridges.

scholarly journals A Practical Approach to the Investigation of Amino Acid Disorders

1988 ◽  
Vol 25 (2) ◽  
pp. 129-141 ◽  
Author(s):  
M A Edwards ◽  
S Grant ◽  
A Green
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Analysis ◽  
Practical Approach ◽  
The Common ◽  
Common Problems

We have, in this paper, highlighted some of the common problems in amino acid analysis in our experience and listed the possible causes for increases in specific amino acids in urine—together with guidance on appropriate follow-up investigations.

scholarly journals Nutritional Profiling and the Value of Processing By-Products from Gilthead Sea Bream (Sparus aurata)

Marine Drugs ◽  
2020 ◽  
Vol 18 (2) ◽  
pp. 101 ◽  
Author(s):  
Mirian Pateiro ◽  
Paulo E. S. Munekata ◽  
Rubén Domínguez ◽  
Min Wang ◽  
Francisco J. Barba ◽  
...  
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Amino Acid ◽  
Mineral Content ◽  
Value Added ◽  
Amino Acid Profile ◽  
Gilthead Sea Bream ◽  
Sea Bream ◽  
Fish Processing ◽  
By Products

Fish processing industries generate a large volume of discards. In order to fulfil with the principles of a sustainable circular economy, it is necessary to maintain aquaculture by-products in the food chain through the production of high-value biomolecules that can be used as novel ingredients. In this study, we try to give value to the gilthead sea bream by-products, evaluating the composition and the nutritional value of the muscle and six discards commonly obtained from the fish processing industry (fishbone, gills, guts, heads, liver, and skin), which represent ≈ 61% of the whole fish. Significant differences were detected among muscle and by-products for fatty acid and amino acid profile, as well as mineral content. The discards studied were rich in protein (10%–25%), showing skin and fishbone to have the highest contents. The amino acid profile reflected the high quality of its protein, with 41%–49% being essential amino acids—lysine, leucine, and arginine were the most abundant amino acids. Guts, liver, and skin were the fattiest by-products (25%–35%). High contents of polyunsaturated fatty acids (PUFAs) (31%–34%), n-3 fatty acids (12%–14%), and eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) (6%–8%) characterized these discards. The head displayed by far the highest ash content (9.14%), which was reflected in the mineral content, especially in calcium and phosphorous. These results revealed that gilthead sea bream by-products can be used as source of value-added products such as protein, oils, and mineral supplements.

Sign in / Sign up

Export Citation Format

Share Document