scholarly journals New functional copolymers of 1-vinyl-1,2,4-triazole with allylamine

2020 ◽  
Vol 10 (3) ◽  
pp. 536-540
Author(s):  
G. F. Prozorova ◽  
A. I. Emel’yanov ◽  
S. A. Korzhova
Keyword(s):  
Molecular Weight ◽  
Organic Semiconductors ◽  
High Resistance ◽  
Gel Permeation Chromatography ◽  
Water Soluble ◽  
Biologically Active ◽  
Specific Electrical Conductivity ◽  
Radical Initiation ◽  
Free Radical Initiation ◽  
Inorganic Nanocomposites

New water-soluble functional copolymers based on 1-vinyl-1,2,4-triazole and allylamine were synthesized under the action of free-radical initiation conditions and azobisisobutyric acid dinitrile. Сopolymers of various compositions with a molecular weight of 1287–30204 Da were obtained by varying reaction conditions. The structure, molecular weight and physicochemical properties of the copolymers were determined using elemental analysis, IR and NMR 1H-spectroscopy, gel permeation chromatography, potentiometric and turbidimetric titration, as well as dynamic light scattering and thermogravimetric analysis. It was established that the obtained copolymers, exhibiting the properties of high-resistance organic semiconductors, are characterized by a specific electrical conductivity of 10-13 – 10-14 S/cm and high resistance to thermal destruction (up to 260–280 °C). These copolymers are promising as stabilizing polymer matrices in the formation of biologically active water-soluble hybrid organic-inorganic nanocomposites.

scholarly journals Features of the hemicellulose structure of some species of regional raw materials and products of their enzymatic hydrolysis

2018 ◽  
Vol 12 (3) ◽  
Author(s):  
O. Nikitina ◽  
N. Cherno ◽  
S. Ozolina
Keyword(s):  
Molecular Weight ◽  
Enzymatic Hydrolysis ◽  
Pleurotus Ostreatus ◽  
Supramolecular Structure ◽  
Main Chain ◽  
Treatment Time ◽  
Water Soluble ◽  
Biologically Active ◽  
Raw Material ◽  
Helical Conformation

Nowadays, it is recognized that a lot of polysaccharides are biologically active. It is well known that these biomolecules show the highest level of their activity if they are water-soluble preparations, their molecular weight being 15–25 kDa, and if they preserve the supramolecular structure of carbohydrates. Basing on the fact that β-glucans of mushrooms are characterized by the antitumor, anticoagulant, anti-inflammatory, and immunomodulatory activities, it is important to determine whether regional raw material contains polysaccharides of a similar structure, and to define the conditions for their fragmentation to obtain products with a given molecular weight. The purpose of the work was to characterize the features of the structure of the hemicellulose complex of the Agaricus bisporous and Pleurotus ostreatus and products of their limited enzymatic hydrolysis. To determine the primary structure of hemicellulose polysaccharides, the 1H-NMR spectra of the samples were registered. It has been shown that β-D-(1→3)/β-(1→6)-glucan dominates in the hemicellulose of Pleurotus ostreatus. Among the hemicelluloses in the Agaricus bisporis, the main polysaccharide was galactoglucan. Its main chain consisted of β-D-glucopyranose residues interconnected with (1→3)-glucosidic bonds. The positions of O-6 monosaccharide are joined by the side branches in the form of β-D-glucopyranoses and the terminal residues of β-D-galactopyranoses. The hemicelluloses of Pleurotus ostreatus also contain manogalactan. Complexes of hemicelluloses of both types of mushrooms contain linear α-(1→3)-glucan in small quantities. It has been studied how the molecular-weight distribution of products of limited hydrolysis of hemicelluloses depends on the conditions of their treatment with the enzyme with β-(1→3)-glucanase activity. The maximum accumulation of a fraction with a given molecular weight of 15–25 kDa was observed at a ratio of E:S = 1:45 and treatment time of 21 hours. A specific reaction with congo red has proved there is a triple helical conformation of the main chain of the polysaccharide for this fraction of carbohydrates, so the supramolecular structure of the molecule is preserved.  

Bioactive and immunoreactive variants of prolactin in milk and serum of lactating rats and their pups

1993 ◽  
Vol 138 (2) ◽  
pp. 243-257 ◽  
Author(s):  
B. Kacsóh ◽  
Z. Veress ◽  
B. E. Tóth ◽  
L. M. Avery ◽  
C. E. Grosvenor
Keyword(s):  
Interleukin 2 ◽  
Gel Permeation Chromatography ◽  
Maternal Serum ◽  
Water Soluble ◽  
Biologically Active ◽  
Neonatal Rat ◽  
Rat Serum ◽  
Rat Pups ◽  
Gel Permeation

ABSTRACT Prolactin (PRL)-like bioactivity (in Nb2 lymphoma assay) and immunoreactivity (in radioimmunoassay (RIA)) in rat milk, maternal and neonatal sera and in neonatal rat pituitary cultures were investigated. The PRL-like bioactivity in the water-soluble fraction of rat milk was high and exceeded its immunoreactivity 5·8-, 4·0- and 2·1-fold, on days 2, 12 and 22 of lactation respectively. The elevated bioactivity to immunoreactivity (B/I) ratio of PRL in milk was not due to the presence of interleukin-2 (IL-2) in milk, since the proliferation of the CTLL-2 murine T cells, which are not sensitive to PRL, was promoted by IL-2 but not by milk. Serum levels of immunoreactive PRL were low in sera of non-weaned rat pups on days 2, 12 and 22 postpartum. Similar to milk, the B/I ratio of PRL in sera of rat pups was high and decreased with time postpartum. Pituitary glands of pups obtained on days 2, 12 and 22 secreted progressively increasing amounts of PRL in vitro; the B/I ratio ranged between 1·2 and 2·1 without a significant change. The relative concentrations of size variants in milk were not proportional to those in serum of lactating rats on day 2 postpartum as assessed by Sepharcryl S-100 HR gel permeation chromatography and Nb2 bioassay or RIA. Size variants of biologically active PRL were abundant in early milk and gradually diminished as lactation progressed: a partially resolved peak representing monomeric to dimeric PRL variants (relative molecular weights ranging between 18 k and 42 k) became progressively narrower between days 2 and 22. Biologically active and immunoreactive PRLs displayed disparate elution profiles. The elution profile of PRL in sera of neonatal rats on day 2 postpartum was different from that of maternal serum or milk. The major immunological (and possibly biological) PRL-like activity eluted as two adjacent peaks at 2·2 k and 1·5 k, raising the possibility that fragments of milk-borne PRL were absorbed from the gut after partial proteolytic degradation. In contrast with PRL, GH (which is present in rat milk only in minute concentrations) did not show heterogeneity in sera of 2-day-old rat pups in gel permeation chromatography. The present results demonstrate that the concentrations of PRL-like activity in rat milk and newborn rat serum have been grossly underestimated because levels have been measured by RIA. The high B/I ratio of PRL in milk and neonatal sera is due to the presence of PRL-related compounds. The difference between the ontogeny in the B/I ratio of serum and in-vitro secreted PRL might be related to absorption of PRL variants from milk during the early postpartum period. The data suggest that PRL might be modified by the mammary gland and the neonatal gut during its passage from the circulation of the mother to that of the neonatal rat. Journal of Endocrinology (1993) 138, 243–257

scholarly journals Antifungal and Antioxidant Properties of Chitosan Polymers Obtained from Nontraditional Polybius henslowii Sources

Marine Drugs ◽  
2019 ◽  
Vol 17 (4) ◽  
pp. 239 ◽  
Author(s):  
Francisco Avelelas ◽  
André Horta ◽  
Luís F.V. Pinto ◽  
Sónia Cotrim Marques ◽  
Paulo Marques Nunes ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Gel Permeation Chromatography ◽  
Cryphonectria Parasitica ◽  
Fungal Species ◽  
Water Soluble ◽  
Raw Material ◽  
Body Parts ◽  
Chitosan Derivatives

Chitin was extracted from Polybius henslowii, a swimming crab, captured in large quantities throughout the Portuguese coast by purse seine vessels as bycatch. After standard chitin extraction procedures, water-soluble chitosan products were obtained via two different methods: (1) N-acetylation with the addition of acetic anhydride and (2) a reaction with hydrogen peroxide. The chemical structure and molecular weight of chitosan derivatives, water-soluble chitosan (WSC) and chitooligosaccharides (COS), were confirmed by Fourier Transform Infrared Spectroscopy (FT-IR) and gel permeation chromatography (GPC). Antioxidant and metal chelation activities were evaluated, and the growth inhibition capacity was tested on four phytopatogens. The chitooligosaccharides from pereopods (pCOS) and shell body parts (sCOS) inhibited all fungal species tested, particularly Cryphonectria parasitica with 84.7% and 85.5%, respectively. Both radical scavenging and antifungal activities proved to be dose-dependent. Chitooligosaccharides with a low molecular weight (2.7, 7.4, and 10.4 Kg·mol−1) showed the highest activity among all properties tested. These results suggested that chitosan derivatives from P. henslowii raw material could potentially be used against phytopathogens or as ingredient in cosmetics and other products related to oxidative stress.

scholarly journals Obtaining and estimating the potential of protein nutraceuticals from highly mineralized collagen-containing beef raw materials

2021 ◽  
Vol 6 (1) ◽  
pp. 10-22
Author(s):  
N. Yu. Mezenova ◽  
S. V. Agafonova ◽  
O. Ya. Mezenova ◽  
L. S. Baidalinova ◽  
T. Grimm
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Amino Acid ◽  
Raw Materials ◽  
Water Soluble ◽  
Biologically Active ◽  
Low Molecular Weight ◽  
Enzyme Preparations ◽  
Freeze Dried ◽  
Mineralized Collagen

Highly mineralized collagen-containing beef raw materials (tibia, fibula and costal bones) are a source of valuable protein nutraceuticals. They include high molecular weight proteins, oligopeptides and amino acids, which anabolic and physiological potential is used insufficiently. Protein nutraceuticals were obtained by high-temperature hydrolysis of beef raw materials in combination with enzymolysis by proteolytic enzyme preparations Alcalase 2,5 L, Protamex, Protosubtilin G3x. The water-soluble fraction of hydrolysates was studied after its separation and freeze-drying on the content of nitrogenous compounds, fats, minerals, formol-titrated nitrogen, fractional molecular composition. The mathematical dependencies of accumulation of low molecular weight products of protein hydrolysis on enzymolysis duration and doses of different enzyme preparations were obtained. The rational technological scheme of complex processing of beef raw materials with production of protein, fat and mineral-protein additives was proposed. The protein weight fraction in the freeze-dried protein hydrolysates was 69.5–89.6%. All studied protein additives contained peptides with a molecular weight of not more than 100 kDa. The content of low-molecular weight oligopeptides with a molecular weight of less than 10 kDa in the protein additives obtained by enzymatic thermal hydrolysis was more than 90%. The amino acid composition of protein additives produced by different hydrolytic methods was analyzed. Sensory and functional-technological properties of freeze-dried protein compositions were studied. The amino acid potential, high assimilability and physiological activity of protein nutraceuticals from collagen-containing beef raw materials were established. It is recommended to use them in the composition of specialized biologically active additives (BAAs) to food of the osteotropic direction in recipes of specialized and personalized products as a source of amino acids and active peptides.

scholarly journals Study on Preparation of Water-Soluble Chitosan with Varying Molecular Weights and Its Antioxidant Activity

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Dang Xuan Du ◽  
Bui Xuan Vuong
Keyword(s):  
Molecular Weight ◽  
Antioxidant Activity ◽  
Dose Range ◽  
Average Molecular Weight ◽  
Gel Permeation Chromatography ◽  
Chitosan Solution ◽  
Water Soluble ◽  
Molecular Weights ◽  
Ph Level ◽  
The One

The preparation of water-soluble chitosan (WSC) with various molecular weights by gamma Co-60 irradiation of chitosan solution (5%) in the presence of hydrogen peroxide (1%) combined with acetylated reaction was carried out. The average molecular weight (Mw) of chitosan was measured by gel permeation chromatography (GPC). The chemical structure and the crystallinity of chitosan and WSC were characterized by Fourier-transform infrared (FT-IR) spectroscopy and X-ray diffraction (XRD), respectively. The antioxidant activity of WSC and chitosan was investigated using the free radical 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS•+). Obtained results showed that chitosan with Mw of 18–90 kDa could be efficiently prepared by this technique in the dose range from 10 to 24.5 kGy. After the acetylated process, the resulting WSC possesses good solubility in a wide pH level of 2–12, and WSC with low molecular weight exhibited significantly higher antioxidant activity than the one with high molecular weight. In detail, the antioxidant activity was 14.7%, 70.5%, 84.2%, 89.4%, and 97.5% for WSC samples prepared from chitosan with Mw of 140.2 kDa, 91.4 kDa, 51.2 kDa, 35.3 kDa, and 18.1 kDa, respectively, at the same reaction time of 90 min. Moreover, the antioxidant activity of WSC was higher than that of chitosan. Thus, WSC prepared by gamma Co-60 irradiation and acetylated process can be potentially applied as a natural antioxidant agent.

The Use of Styrenes as Embedding Media for Electron Microscopy

1971 ◽  
Vol 29 ◽  
pp. 488-489
Author(s):  
Edward D. De-Lamater ◽  
Eric Johnson ◽  
Thad Schoen ◽  
Cecil Whitaker
Keyword(s):  
Electron Microscopy ◽  
Surface Tension ◽  
Ultraviolet Light ◽  
Methyl Ethyl Ketone Peroxide ◽  
Methyl Ethyl ◽  
Styrene Polymerization ◽  
Radical Initiation ◽  
Tertiary Butyl ◽  
Low Viscosity ◽  
Free Radical Initiation

Monomeric styrenes are demonstrated as excellent embedding media for electron microscopy. Monomeric styrene has extremely low viscosity and low surface tension (less than 1) affording extremely rapid penetration into the specimen. Spurr's Medium based on ERL-4206 (J.Ultra. Research 26, 31-43, 1969) is viscous, requiring gradual infiltration with increasing concentrations. Styrenes are soluble in alcohol and acetone thus fitting well into the usual dehydration procedures. Infiltration with styrene may be done directly following complete dehydration without dilution.Monomeric styrenes are usually inhibited from polymerization by a catechol, in this case, tertiary butyl catechol. Styrene polymerization is activated by Methyl Ethyl Ketone peroxide, a liquid, and probably acts by overcoming the inhibition of the catechol, acting as a source of free radical initiation.Polymerization is carried out either by a temperature of 60°C. or under ultraviolet light with wave lengths of 3400-4000 Engstroms; polymerization stops on removal from the ultraviolet light or heat and is therefore controlled by the length of exposure.

Antithrombin III Binding to Surface Immobilized Heparin and Its Relation to F Xa Inhibition

1987 ◽  
Vol 58 (04) ◽  
pp. 1064-1067 ◽  
Author(s):  
K Kodama ◽  
B Pasche ◽  
P Olsson ◽  
J Swedenborg ◽  
L Adolfsson ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Ionic Strength ◽  
Surface Coating ◽  
Antithrombin Iii ◽  
Lower Class ◽  
Biologically Active ◽  
High Affinity ◽  
Heparin Coating ◽  
Continuous Surface ◽  
Approximate Molecular Weight

SummaryThe mode of F Xa inhibition was investigated on a thromboresistant surface with end-point attached partially depoly-merized heparin of an approximate molecular weight of 8000. Affinity chromatography revealed that one fourth of the heparin used in surface coating had high affinity for antithrombin III (AT). The heparin surface adsorbed AT from both human plasma and solutions of purified AT. By increasing the ionic strength in the AT solution the existence of high and low affinity sites could be shown. The uptake of AT was measured and the density of available high and low affinity sites was found to be in the range of 5 HTid 11 pic.omoles/cmf, respectively Thus the estimated density of biologically active high and low ailmity heparm respectively would be 40 and 90 ng/cm2 The heparin coating did not take up or exert F Xa inhibition by itself. With AT adsorbed on both high and low affinity heparin the surface had the capacity to inhibit several consecutive aliquots of F Xa exposed to the surface. When mainly high affinity sites were saturated with AT the inhibition capacity was considerably lower. Tt was demonstrated that the density of AT on both high and low affinity heparin determines the F Xa inhibition capacity whereas the amount of AT on high affinity sites limits the rate of the reaction. This implies that during the inhibition of F Xa there is a continuous surface-diffusion of AT from sites of a lower class to the high affinity sites where the F Xa/AT complex is formed and leaves the surface. The ability of the immobilized heparin to catalyze inhibition of F Xa is likely to be an important component for the thromboresistant properties of a heparin coating with non-compromized AT binding sequences.

ANALISA KANDUNGAN BETA-GLUKAN LARUT AIR DAN LARUT ALKALI DARI TUBUH BUAH JAMUR TIRAM (Pleurotus ostreatus) DAN SHIITAKE (Lentinus edodes)

2013 ◽  
Vol 13 (3) ◽  
Author(s):  
Netty Widyastuti ◽  
Teguh Baruji ◽  
Henky Isnawan ◽  
Priyo Wahyudi ◽  
Donowati Donowati
Keyword(s):  
Molecular Structure ◽  
Molecular Weight ◽  
Immune System ◽  
Pleurotus Ostreatus ◽  
Water Soluble ◽  
Low Molecular Weight ◽  
Lentinus Edodes ◽  
Beta Glucan ◽  
Oyster Mushrooms ◽  
The Difference

Beta glucan is a polysaccharide compound, generally not soluble inwater and resistant to acid. Beta glucan is used as an immunomodulator (enhancing the immune system) in mammals is usually a beta-glucan soluble in water, easily absorbed and has a low molecular weight. Several example of beta-glucan such as cellulose (β-1 ,4-glucan), lentinan (β-1 0.6-glucan) and (β-1 ,3-glucan), pleuran (β-1, 6 and β-1 ,3-glucan) are isolated from species of fungi Basidiomycota include mushrooms (Pleurotus ostreatus) and shiitake (Lentinus edodes).The purpose of thisresearch activity is to obtain beta-glucan compound that can be dissolved in water and in alkali derived from fungi Basidiomycota, i.e, Oyster mushrooms (Pleurotus ostreatus) and shiitake (Lentinus edodes). The result of beta-glucan compared to characterize the resulting beta glucan that is molecular structure . The difference of beta glucan extraction is based on the differences in solubility of beta-glucan. Beta glucan could be water soluble and insoluble water.

The content of decenoic acids in drone brood preparations and combined preparations based on it

Biomics ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 389-393
Author(s):  
D.V. Mitrofanov ◽  
N.V. Budnikova
Keyword(s):  
Royal Jelly ◽  
Storage Conditions ◽  
Water Soluble ◽  
Biologically Active Substances ◽  
Biologically Active ◽  
Strict Adherence ◽  
Drone Brood ◽  
Wide Range ◽  
Active Substances ◽  
Melanin Complex

The drone brood contains a large number of substances with antioxidant activity. These substances require stabilization and strict adherence to storage conditions. Among these substances are unique decenoic acids, the content of which is an indicator of the quality of drone brood and products based on it. The ability of drone brood to reduce the manifestations of oxidative stress is shown. There are dietary supplements for food and drugs based on drone brood, which are used for a wide range of diseases. Together with drone brood, chitosan-containing products, propolis, royal jelly can be used. They enrich the composition with their own biologically active substances and affect the preservation of the biologically active substances of the drone brood. Promising are the products containing, in addition to the drone brood, a chitin-chitosan-melanin complex from bees, propolis, royal jelly. The chitin-chitosan-melanin complex in the amount of 5% in the composition of the adsorbent practically does not affect the preservation of decenic acids, while in the amount of 2% and 10% it somewhat worsens. The acid-soluble and water-soluble chitosan of marine crustaceans significantly worsens the preservation of decenoic acids in the product. Drone brood with royal jelly demonstrates a rather high content of decenoic acids. When propolis is introduced into the composition of the product, the content of decenoic acids increases according to the content of propolis.

Relative Reactivities of 1,1,1-Trichloroethane and 1,1,1-Trichlorotrifluoroethane in Competitive Addition Reactions

1992 ◽  
Vol 57 (6) ◽  
pp. 1291-1298 ◽  
Author(s):  
František Adámek ◽  
Milan Hájek ◽  
Zbyněk Janoušek
Keyword(s):  
Free Radical ◽  
Reaction Mechanism ◽  
Relative Reactivity ◽  
Addition Reactions ◽  
Radical Initiation ◽  
Amine Complexes ◽  
Free Radical Initiation ◽  
Ru Complexes ◽  
Radical Initiators

Relative reactivity of CH3CCl3 and CF3CCl3 measured in competitive addition reactions with 1-hexene in the presence of free radical initiators or Cu, Pd and Ru complexes was found to depend on the type of catalyst. The unusual course of the reaction has been found in the additions catalyzed with copper(I)-amine complexes where CH3CCl3 in competition with CF3CCl3 was completely unreactive. The results have been explained in terms of the change of reaction mechanism and compared with classical free radical initiation.

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