scholarly journals The chemistry of branched condensed phosphates

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Tobias Dürr-Mayer ◽  
Danye Qiu ◽  
Verena B. Eisenbeis ◽  
Nicole Steck ◽  
Markus Häner ◽  
...  
Keyword(s):  
Amino Acids ◽  
Prebiotic Chemistry ◽  
Chemical Properties ◽  
Entry Point ◽  
Biological Relevance ◽  
Condensed Phosphates ◽  
Branched Structures ◽  
Branched Structure ◽  
General Synthesis

AbstractCondensed phosphates may exist as linear, cyclic or branched structures. Due to their important role in nature, linear polyphosphates have been well studied. In contrast, branched phosphates (ultraphosphates) remain largely uncharacterised, because they were already described in 1950 as exceedingly unstable in the presence of water, epitomized in the antibranching-rule. This rule lacks experimental backup, since, to the best of our knowledge, no rational synthesis of defined ultraphosphates is known. Consequently, detailed studies of their chemical properties, reactivity and potential biological relevance remain elusive. Here, we introduce a general synthesis of monodisperse ultraphosphates. Hydrolysis half-lives up to days call the antibranching-rule into question. We provide evidence for the interaction of an enzyme with ultraphosphates and discover a rearrangement linearizing the branched structure. Moreover, ultraphosphate can phosphorylate nucleophiles such as amino acids and nucleosides with implications for prebiotic chemistry. Our results provide an entry point into the uncharted territory of branched condensed phosphates.

ADAPTIVE CAPACITY OF EINKORN HUSKLESS IN THE SECOND, THIRD AND SEVENTH RUSSIAN FEDERATION REGIONS

1970 ◽  
pp. 34-38
Author(s):  
S. K. Temirbekova ◽  
M. Sh. Begeulov ◽  
Yu. V. Afanaseva ◽  
I. M. Kulikov ◽  
N. E. Ionova
Keyword(s):  
Amino Acids ◽  
Biochemical Analysis ◽  
Chemical Properties ◽  
First Grade ◽  
Essential Amino Acids ◽  
Wheat Grain ◽  
Volume Yield ◽  
Class 1 ◽  
Group B ◽  
Field And Laboratory Conditions

Biochemical, immunological and physico-chemical properties of an ancient wheat grain – hulless spelt cultivar Gremme are investigated. Biochemical analysis of grain revealed a high content of protein, fiber, macro-and microelements, a rich composition of essential amino acids, which is characteristic of ancient wheat species. Evaluated milling and baking properties of spelt flour. Physical and chemical parameters of spelt grain met the requirements for soft wheat grain class 1: the mass fraction of gluten-38.7 %, the nature of the grain-795 g / l, the number of drops-416 C, the total vitreousness-70 %. However, gluten had an increased stickiness, which is obviously due to the increased content of fiber and gliadin fraction. Grinding of spelt grain was carried out on the aggregate mill installation "Miller 100 Lux" to obtain baking flour of various cultivars. The overall yield of flour of the first grinding was 59.7 %. The highest volume yield (359 cm3) and the best organoleptic properties (total baking score – 3.6 points) were observed in a sample of bread baked from spelt flour that meets the requirements for wheat baking flour of the first grade. Studies have confirmed the possibility of using flour produced from the spelt grain of the Gremme variety for the production of bakery products of increased biological, therapeutic and prophylactic, nutritional value and with a high organoleptic rating. Cereals and flour are very rich in trace elements-manganese, selenium, zinc, potassium, iron, phosphorus, vitamins from group B and B, essential amino acids (biochemical analysis was carried out by the Cherkizovo Center). The cultivar is resistant to drought, heat, excessive moisture. Proved immunological properties to several diseases in the field and laboratory conditions-resistant to enzyme-mycotic seed depletion (EMIS), various types of rust, powdery mildew.

scholarly journals Synthesis, Characterization and Evaluation of Peptide Nanostructures for Biomedical Applications

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4587
Author(s):  
Fanny d’Orlyé ◽  
Laura Trapiella-Alfonso ◽  
Camille Lescot ◽  
Marie Pinvidic ◽  
Bich-Thuy Doan ◽  
...  
Keyword(s):  
Amino Acids ◽  
Biomedical Applications ◽  
Chemical Reactivity ◽  
Physical Stability ◽  
Chemical Properties ◽  
Building Blocks ◽  
Imaging Probes ◽  
Therapeutic Molecules

There is a challenging need for the development of new alternative nanostructures that can allow the coupling and/or encapsulation of therapeutic/diagnostic molecules while reducing their toxicity and improving their circulation and in-vivo targeting. Among the new materials using natural building blocks, peptides have attracted significant interest because of their simple structure, relative chemical and physical stability, diversity of sequences and forms, their easy functionalization with (bio)molecules and the possibility of synthesizing them in large quantities. A number of them have the ability to self-assemble into nanotubes, -spheres, -vesicles or -rods under mild conditions, which opens up new applications in biology and nanomedicine due to their intrinsic biocompatibility and biodegradability as well as their surface chemical reactivity via amino- and carboxyl groups. In order to obtain nanostructures suitable for biomedical applications, the structure, size, shape and surface chemistry of these nanoplatforms must be optimized. These properties depend directly on the nature and sequence of the amino acids that constitute them. It is therefore essential to control the order in which the amino acids are introduced during the synthesis of short peptide chains and to evaluate their in-vitro and in-vivo physico-chemical properties before testing them for biomedical applications. This review therefore focuses on the synthesis, functionalization and characterization of peptide sequences that can self-assemble to form nanostructures. The synthesis in batch or with new continuous flow and microflow techniques will be described and compared in terms of amino acids sequence, purification processes, functionalization or encapsulation of targeting ligands, imaging probes as well as therapeutic molecules. Their chemical and biological characterization will be presented to evaluate their purity, toxicity, biocompatibility and biodistribution, and some therapeutic properties in vitro and in vivo. Finally, their main applications in the biomedical field will be presented so as to highlight their importance and advantages over classical nanostructures.

STUDY OF AMINO ACID MODIFIERS IN GUAYULE NATURAL RUBBER

2015 ◽  
Vol 88 (2) ◽  
pp. 310-323 ◽  
Author(s):  
Colleen McMahan ◽  
Dhondup Lhamo
Keyword(s):  
Amino Acids ◽  
Natural Rubber ◽  
Oxidative Stability ◽  
Chemical Properties ◽  
The United States ◽  
Thermal Oxidative Stability ◽  
Green Strength ◽  
Strain Induced Crystallization ◽  
New Perspective ◽  
Physical And Chemical

ABSTRACT Guayule, a desert shrub indigenous to the United States, is under development as a source of natural rubber that can be used in place of petroleum-based rubber or Hevea rubber. In natural rubbers, physical and chemical properties can be strongly affected by nonrubber constituents, typically proteins and lipids, present in the material, depending on the plant species and postharvest processing. Hevea natural rubber typically contains high levels of nonrubber constituents that contribute to thermal-oxidative stability, cure acceleration, and especially strain-induced crystallization. The latter has been attributed to compound properties that render Hevea natural rubber uniquely suited for the most demanding rubber applications (e.g., aircraft tires). Hevea proteins are susceptible to hydrolysis, releasing free amino acids into the latex, which can affect rubber and compound properties. Here, low-protein guayule latex was blended with a series of amino acids varying in chemical structure. Bulk viscosity was reduced, thermal-oxidative stability was improved, and cure rate was influenced by the addition of amino acids. Generally, gel formation, green strength, and tensile strength were not affected. The results introduce a new perspective for amino acids as biobased rubber compound additives and provide insights into naturally occurring nonrubber constituents' interaction with natural rubber polymers.

scholarly journals How do campsites, forest fires, and entry point distance affect earthworm abundance in the Boundary Waters Canoe Area Wilderness?

2019 ◽  
Author(s):  
Todd A Wellnitz ◽  
Jenna L Barlow ◽  
Cory M Dick ◽  
Terrance R Shaurette ◽  
Brian M Johnson ◽  
...  
Keyword(s):  
Species Richness ◽  
Forest Fires ◽  
Negative Relationship ◽  
Chemical Properties ◽  
Entry Point ◽  
Invasive Earthworms ◽  
Earthworm Biomass ◽  
Point Distance ◽  
Physical And Chemical ◽  
Properties Of Soil

Factors controlling the spread of invasive earthworms in Minnesota’s Boundary Waters Canoe Area Wilderness are poorly known. Believed to have been introduced by anglers who use them as bait, invasive earthworms can alter the physical and chemical properties of soil and modify forest plant communities. To examine factors influencing earthworm distribution and abundance, we sampled 38 islands across five lakes to assess the effects of campsites, fire, and entry point distance on earthworm density, biomass and species richness. We hypothesized that all three parameters would be greater on islands with campsites, lower on burned islands, and would decrease with distance from the wilderness entry point. In addition to sampling earthworms, we collected soil cores to examine soil organic matter and recorded ground and vegetation cover. Campsite presence was the single most important factor affecting sampled earthworm communities; density, biomass and species richness were all higher on islands having campsites. Fire was associated with reduced earthworm density, but had no direct effects on earthworm biomass or species richness. Fire influenced earthworm biomass primarily through its negative relationship to groundcover and through an interaction with entry point distance. Distance affected density but no other factor. For islands with campsites, however, distance from the entry point had a counterintuitive effect in that earthworm biomass, which increased with entry point distance.

New, Highly Structured Carbon Black of the OMCARB Series for Reducing the Hysteresis in Rubber. Part 1. Features of the Structure and Properties of Carbon Black

2016 ◽  
Vol 43 (12) ◽  
pp. 17-22
Author(s):  
G.V. Moiseevskaya ◽  
G.I. Razd'yakonova ◽  
A.A. Petin ◽  
E.A. Strizhak
Keyword(s):  
Carbon Black ◽  
Chemical Properties ◽  
Morphological Characteristics ◽  
Structural Data ◽  
Structure And Properties ◽  
Elastomeric Materials ◽  
Rubber Part ◽  
Average Size ◽  
Branched Structure ◽  
And Chemical Properties

The aim of this work was to study the properties of carbon black CH85 of the OMCARB series and to compare them with the properties of standard carbon blacks N339 and N234. The morphological characteristics, the size distribution of the globules and aggregates, the surface area, the proportion of micropore area, the degree of branching of aggregates, and also the mechanical and chemical properties were measured and calculated. The average size of the aggregates of CH85 is greater than that of N339 and N234, and the aggregates have a more open and branched structure. The iodine adsorption by CH85 is practically the same as that by N339 and lower than that by N234. The low-hysteresis index calculated on the basis of structural data is much better for CH85. This opens up the possibility of using this type of carbon black for the development of elastomeric materials with low hysteresis.

scholarly journals Analysis of amino acids in human tears by hydrophilic interaction liquid chromatography and quadrupole orbitrap mass spectrometry

RSC Advances ◽  
2019 ◽  
Vol 9 (63) ◽  
pp. 36539-36545
Author(s):  
Chi-Xin Du ◽  
Zhu Huang
Keyword(s):  
Mass Spectrometry ◽  
Amino Acids ◽  
Liquid Chromatography ◽  
Chemical Properties ◽  
Hydrophilic Interaction Liquid Chromatography ◽  
Hydrophilic Interaction ◽  
Orbitrap Mass Spectrometry

Amino acids in human tears play certain physiological roles and their determination is challenging due to complicated chemical properties.

EFFECT OF PROTEIN ADDITION ON PROPERTIES OF GUAYULE NATURAL RUBBER

2017 ◽  
Vol 90 (2) ◽  
pp. 387-404 ◽  
Author(s):  
Dhondup Lhamo ◽  
Colleen McMahan
Keyword(s):  
Amino Acids ◽  
Natural Rubber ◽  
Oxidative Stability ◽  
Chemical Properties ◽  
Green Strength ◽  
Truck Tires ◽  
Oxidative Resistance ◽  
Strain Induced Crystallization ◽  
General Protein ◽  
Physical And Chemical

ABSTRACT Parthenium argentatum, commonly known as guayule, is a desert shrub cultivated as a domestic source of natural rubber in the semi-arid southwestern United States. Guayule natural rubber (GR) may be used to replace petroleum-based rubber or in place of Hevea natural rubber (NR), but substitution must take into consideration differences in physical and chemical properties. Currently, Hevea NR is required in tire applications, especially aircraft and truck tires, because of its high oxidative resistance, rapid cure rate, and exceptional stress–strain response. These outstanding features are attributed to the presence of nonrubber constituents, mainly proteins and lipids, which cause the rubber to gel, and they contribute to strain-induced crystallization. In contrast, GR is low in proteins and is thus deprived of some attributes of Hevea. Addition of amino acids and proteins to guayule could potentially improve performance and thereby widen the range of applications for use. In a previous study, amino acids blended with GR latex improved thermo-oxidative stability, served as plasticizers and cure accelerators, and enhanced green strength slightly, but tensile strength was not improved. Here, a series of bio-based commercial proteins (gelatin, soy, albumin, casein, zein, gliadin, and gluten) were added to GR as a latex blend. In general, protein addition reduced bulk viscosity and improved thermo-oxidative stability. The gel content and green strength of the polymer–protein blends were increased, with the exception of gliadin, but not to levels observed for Hevea. Effects on vulcanization and mechanical properties in compounds were surprisingly influenced by the choice of antioxidants used. Our results demonstrate the potential of proteins as bio-based rubber compounding additives.

scholarly journals Porin from Marine Bacterium Marinomonas primoryensis KMM 3633T: Isolation, Physico-Chemical Properties, and Functional Activity

Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3131
Author(s):  
Olga D. Novikova ◽  
Valentina A. Khomenko ◽  
Natalia Yu. Kim ◽  
Galina N. Likhatskaya ◽  
Lyudmila A. Romanenko ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Lipid Membranes ◽  
Marine Bacterium ◽  
Chemical Properties ◽  
Cell Permeability ◽  
Oligomeric Structure ◽  
Black Lipid Membranes ◽  
Physico Chemical ◽  
Coastal Sea

Marinomonas primoryensis KMM 3633T, extreme living marine bacterium was isolated from a sample of coastal sea ice in the Amursky Bay near Vladivostok, Russia. The goal of our investigation is to study outer membrane channels determining cell permeability. Porin from M. primoryensis KMM 3633T (MpOmp) has been isolated and characterized. Amino acid analysis and whole genome sequencing were the sources of amino acid data of porin, identified as Porin_4 according to the conservative domain searching. The amino acid composition of MpOmp distinguished by high content of acidic amino acids and low content of sulfur-containing amino acids, but there are no tryptophan residues in its molecule. The native MpOmp existed as a trimer. The reconstitution of MpOmp into black lipid membranes demonstrated its ability to form ion channels whose conductivity depends on the electrolyte concentration. The spatial structure of MpOmp had features typical for the classical gram-negative porins. However, the oligomeric structure of isolated MpOmp was distinguished by very low stability: heat-modified monomer was already observed at 30 °C. The data obtained suggest the stabilizing role of lipids in the natural membrane of marine bacteria in the formation of the oligomeric structure of porin.

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