scholarly journals REACTIONS OF HYDROXIBENZOIC ACIDS WITH 2-AMIDINOPROPAN-2-PEROXYL IN ACID MEDIA

2020 ◽  
pp. 81-95
Author(s):  
Александр Владимирович Белый ◽  
Наталья Ивановна Белая ◽  
Виктор Сергеевич Дорошкевич
Keyword(s):  
Antiradical Activity ◽  
Aqueous Media ◽  
Peroxyl Radicals ◽  
Chemiluminescence Method ◽  
Acid Media ◽  
Antiradical Properties ◽  
Hydroxybenzoic Acids ◽  
Semi Empirical ◽  
The Relationship ◽  
Factor Equation

Методом хемилюминесценции определена реакционная способность гидроксибензойных кислот при взаимодействии с 2-амидинопропан-2-пероксильными радикалами, генерированными при термическом распаде азоинициатора 2,2ʹ-азобис(2-амидинопропан) дигидрохлорида в фосфатном буфере при рН=2. Установлена зависимость между антирадикальной активностью и молекулярными дескрипторами кислот, связанными с механизмом их антирадикального действия, в виде полуэмпирического линейного однофакторного уравнения. Полученная связь «дескриптор-активность» может быть основой для прогнозирования антирадикальных свойств фенолокислот и подобных им структур в водных средах. The reactivity of hydroxybenzoic acids in the reaction with 2-amidinopropane-2-peroxyl radicals generated by thermal decomposition of azoinitiator 2,2ʹ-azobis(2-amidinopropane)dihydrochloride in phosphate buffer at pH=2 was determined using chemiluminescence method. The relationship between the molecular acid descriptors, associated with the mechanism of their antiradical action, and antiradical activity in the form of a semi-empirical linear one-factor equation was established. The obtained «descriptor-activity» relationship can be used as a basis for predicting the antiradical properties of phenolic acids and similar structures in aqueous media.

scholarly journals The antiradical activity of plant extracts and healthful preventive combinations of these exrtacts with the phospholipid complex

2012 ◽  
Vol 58 (6) ◽  
pp. 712-726 ◽  
Author(s):  
V.S. Baranova ◽  
I.F. Rusina ◽  
D.A. Guseva ◽  
N.N. Prozorovskaya ◽  
O.M. Ipatova ◽  
...  
Keyword(s):  
Plant Extracts ◽  
Hypericum Perforatum ◽  
Antiradical Activity ◽  
Peroxyl Radicals ◽  
Chemiluminescence Method ◽  
Phospholipid Complex ◽  
Aronia Melanocarpa ◽  
Rhaponticum Carthamoides ◽  
Medicinal Treatment ◽  
Synergism Effect

Using the chemiluminescence method, the effective concentration of antioxidants (AO) and its reactivity toward peroxyl radicals (ARA, the k7 constant) have been measured for 13 plant extracts. In fact all extracts demonstrated ARA higher than ionol. Larix dahurica, Hypericum perforatum, Potentilla fruticosa, Aronia melanocarpa and Rhaponticum carthamoides extracts showed the highest values of ARA. The combinations Aronia + Raponticum extracts; Larix + Hibiscus extracts; Schizandra +Aronia extracts were synergistic (the synergism effect β of 38%, 33% and 22%). Apparently this phenomenon is the result of the synergistic interaction between compounds present in plant extracts. The Phospholipid complex - Lipoid S40, lacting any antioxidant effect alone, showed a potent synergistic effect with Aronia extract (β = 60%), Silybum extract (β = 41%). Clinical trials demonstrated, that combinations "Lipoid + Aronia extract", "Lipoid + Larix extract + Hibiscus extract", "Lipoid + Silybum extract", "Lipoid + Q10 + Rosa majalis extract" may be used as an additional component in the medicinal treatment, or as an individual prophylactic agent.

scholarly journals ANTIRADICAL ACTIVITY OF ESSENTIAL OILS OF FILIPENDULA ULMARIA (L.) MAXIM, HYPERICUM PERFORA-TUM L. AND PULMONARIA MOLLIS WULFEN EX HORNEM OF THE KRASNOYRSK TERRITORI FLORA

2021 ◽  
pp. 211-217
Author(s):  
Irina Dement'yevna Zykova ◽  
Aleksandr Alekseyevich Efremov
Keyword(s):  
Essential Oil ◽  
Essential Oils ◽  
Antiradical Activity ◽  
Component Composition ◽  
Salicylic Aldehyde ◽  
Filipendula Ulmaria ◽  
Antiradical Properties ◽  
Hypericum Perforatum L ◽  
Butyl Phthalate ◽  
Main Components

The antiradical properties of essential oils from the inflorescences of Filipendula ulmaria (L). Maxim, herbages Hypericum perforatum L. and Pulmonaria mollis Wulfen ex HORNEM., growing on the territory of the Krasnoyarsk territory were studied. For this purpose, the reaction of essential oil components with a stable free 2,2-diphenyl-1-picrylhydrazyl radical was used. Essential oil of the plants under study received comprehensive hydroponically. The component composition of the oils was determined by chromatography-mass spectrometry. The main components of essential oil of F. ulmaria inflorescences are methyl salicylate (28.2%), salicylic aldehyde (2.8 %) and linalool (4.9%), essential oil of H. perforatum – γ - amorphene (30.7%), δ-cadinen (7.1%), (E, E)-β-farnesene (5.5%), caryophyllene (5.0%), ledol (5.0%), essential oil of P. mollis – di-n-butyl phthalate (18.7%), docosan (13.4%), tetracosan (11.6 %). The results of the DPPH test showed that the essential oils of the inflorescences of F. ulmaria and the aboveground part of H. perforatum and P. mollis exhibit antiradical activity (ARA). According to the size of the ARA of essential oils, the studied plants can be arranged in the following row: P. mollis > F. ulmaria > H. perforatum.

scholarly journals Screen for Potential Candidate Alternatives of Sargentodoxa cuneata from Its Six Adulterants Based on Their Phenolic Compositions and Antioxidant Activities

2019 ◽  
Vol 20 (21) ◽  
pp. 5427 ◽  
Author(s):  
Lingguang Yang ◽  
Peipei Yin ◽  
Xinxin Cao ◽  
Yujun Liu
Keyword(s):  
Plasmid Dna ◽  
Antioxidant Activities ◽  
Peroxyl Radicals ◽  
Potential Candidate ◽  
Total Phenols ◽  
Polygonum Cuspidatum ◽  
Caffeoylquinic Acids ◽  
Phenolic Contents ◽  
Hydroxybenzoic Acids ◽  
Dna Strand

Daxueteng, the liana stem of Sargentodoxa cuneata, is a widely used Traditional Chinese Medicine facing the overflow of its commercial adulterants. A method for discriminating adulterants and screening potential candidate alternatives of S. cuneata was thus established. Total phenols and flavonoids of S. cuneata and its six adulterants and their abilities to scavenge DPPH• and ABTS•+, to absorb peroxyl radicals (ORAC), and to inhibit AAPH-induced supercoiled plasmid DNA strand scission were comprehensively assessed. Polygonum cuspidatum and Bauhinia championii, two of the six adulterants of S. cuneate, shared considerably higher antioxidant activities as well as phenolic contents and, therefore, were considered as potential candidate alternatives. Phenolic compositions of the two potential candidate alternatives and S. cuneata itself were further determined by UPLC-QTOF-MS/MS. Totally 38 phenolics, including four hydroxybenzoic acids, two tyrosols, two caffeoylquinic acids, seven flavanol or its oligomers, two lignans, three hydroxycinnamic acids, six stilbenes, seven anthraquinones, and five flavanones were determined from three species. Furthermore, contents of different phenolic categories were semi-quantified and the major antioxidant contributors of S. cuneata and the two potential candidate alternatives were subsequently determined. It is concluded that tyrosols and caffeoylquinic acids were unique categories making great antioxidant contributions in S. cuneata and thus were considered as effective biomarkers in distinguishing its potential candidate alternatives.

scholarly journals Combined Effect of Sonication and Acid Whey on Antioxidant and Angiotensin-Converting Enzyme Inhibitory Activities of Peptides Obtained from Dry-Cured Pork Loin

2020 ◽  
Vol 10 (13) ◽  
pp. 4521 ◽  
Author(s):  
Paulina Kęska ◽  
Joanna Stadnik
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Antiradical Activity ◽  
Reducing Power ◽  
Sea Salt ◽  
Converting Enzyme ◽  
Antiradical Properties ◽  
Oxidation Reduction ◽  
Sample Range ◽  
Acid Whey ◽  
Inhibitory Activities

This study aimed to determine the effects of sonication and acid whey maceration on the oxidative stability, antioxidant activity and angiotensin-converting enzyme (ACE) inhibitory activity of peptides obtained from dry-cured pork loins. The changes in the selected parameters were documented over 7, 21 and 42 days of storage. The lowest antioxidant and angiotensin-converting enzyme inhibitory activities of peptides were noted in batches with curing salt (C) and acid whey (SW) compared to batches with sea salt (S). In this sample range, the lowest oxidation–reduction power values were associated with the use of ultrasound. In addition, higher antiradical activity (against ABTS•+) and reducing power values were observed for the sea salt ultrasound (SU) batches (after 21 and 42 days) and for the acid whey ultrasound (SWU) batches (after 7 and 21 days). Contrasting results were obtained for samples with sea salt (S and SU), which were characterized by a higher content of peptides, better antiradical properties and the highest potential to inhibit ACE (after seven days).

scholarly journals МОДЕЛЮВАННЯ ВЗАЄМОДІЇ КРИЛЕВОГО ПРОФІЛЮ З ДОЩОВИМ ПОТОКОМ

2020 ◽  
pp. 36-41
Author(s):  
Сергей Евгеньевич Aгеев ◽  
Юрий Петрович Миляев
Keyword(s):  
Water Film ◽  
Aerodynamic Characteristics ◽  
Negative Consequences ◽  
Wing Profile ◽  
Air Interface ◽  
Adopted Model ◽  
Semi Empirical ◽  
Relationship Of ◽  
Surface Tension Forces ◽  
The Relationship

The subject of the study is the analysis of the multilateral impact of rainfall on the flight of a modern aircraft. When considering various factors of this impact, it was found that the main negative consequences of the interaction of the aircraft with the rain flow are the formation of a thin layer of water on its surface, which under the influence of drops and surface tension forces changes the configuration of the wing profile, causing loss of load-bearing properties and an increase in frontal aircraft resistance. The influence of rain flowing around the bearing surfaces can be reduced to taking into account changes in the characteristics of the surface and the flow of the airflow. The goal is to develop a model for the interaction of modern wing profiles with rain flow. The task is to determine the amount of water deposited on the surface of the wing profile, calculate the parameters of the water film formed on its surface, and as a result of this, change the tangential stress at the liquid-air interface. The semi-empirical calculation method used reveals a significant dependence of the amount of precipitated rain water on the surface of modern wing profiles on their geometry and the conditions of interaction with the stream of raindrops. The result of this work is the resulting model, which allows you to simulate the flow conditions around the wing profile in the rain stream and evaluate the relationship of rain intensity with the parameters of the water film that forms on the profile. Conclusions. An analysis of the features of the rain film flow over the surface of the wing profile and its effect on the parameters of the boundary layer shows the negative nature of the effect of rainfall on the aerodynamics of the aircraft. The results obtained allow us to judge the reliability of using the adopted model to calculate the effect of rain on the aerodynamic characteristics of wing profiles, and the possibility of using the results to determine the dependence of the aerodynamic characteristics of wing profiles on the conditions of rainfall molasses.

scholarly journals ANTIRADICAL ACTIVITY OF SEPARATE FRACTIONS OF ESSENTIAL OIL OF ACORUS CALAMUS ROOTS

2020 ◽  
pp. 73-78
Author(s):  
Irina Dement'yevna Zykova ◽  
Aleksandr Alekseyevich Efremov ◽  
Liliya Viktorovna Naimushina
Keyword(s):  
Essential Oil ◽  
Antiradical Activity ◽  
Component Composition ◽  
Biologically Active ◽  
Acorus Calamus ◽  
Siberian Region ◽  
Antiradical Properties ◽  
Main Components ◽  
First Time ◽  
Content Of Oxygen

Essential oil from the roots of calamus marsh (Acorus calamus L) was isolated by the method of exhaustive hydroparodistillation, growing on the Krasnoyarsk territory. Separate fractions of essential oil were obtained depending on the duration of isolation. The component composition of the essential oil, the main components of which are acorenone, butyrate α-terpineol, germacrene B, camphor. The antiradical properties of the essential oil of A. сalamus roots growing in the Siberian region, as well as the antiradical properties of its individual fractions were studied for the first time in order to determine the most promising samples as sources of biologically active complexes. To determine the antiradical activity, the reaction of the essential oil components with a stable free 2,2-diphenyl-1-picrylhydrazyl radical was used. The antiradical activity of all studied samples of essential oils was established. There was an increase in antiradical activity with a decrease in the content of monoterpenes in the composition of the essential oil. The lowest antiradical activity (17.5%) was shown by the fraction of essential oil with a high content of monoterpenes, the highest (~100%) – fractions with a high content of oxygen-containing compounds. It was revealed that the ability of components of individual fractions of A. сalamus essential oil to inhibit DPPH radicals is comparable with the antiradical activity of ascorbic acid solutions of equivalent concentration.

scholarly journals Refinement of the relationship between effective radii and ionization energies of alkali metal atoms

2020 ◽  
Vol 64 (10) ◽  
pp. 7-13
Author(s):  
Victor M. Yakovlev ◽  
◽  
Ivan K. Garkushin ◽  
Alexander V. Burchakov ◽  
◽  
...  
Keyword(s):  
Alkali Metals ◽  
Effective Interaction ◽  
Ionization Energies ◽  
Quantum Numbers ◽  
Analytical Formulas ◽  
Effective Principal ◽  
Simple Power Function ◽  
Semi Empirical ◽  
The Relationship ◽  
Atomic Radii

One of the key explanations for the peculiarities of the change in the first ionization energies (IE Ei1) of the elements of the periodic table is based on the postulation of an unambiguous relationship between Ei1 and atomic radii (rat). Due to the certain conventionality of the rat parameters, they do not belong to the category of attributive atomic characteristics. Usually they are found either by implementing various kinds of theoretical or semi-empirical calculation schemes, or by using experimental data on Ei1 for the corresponding approximations. As follows from the literature data, the known values of rat, even in the case of "quasi-hydrogen-like" alkali metals (AM), –relatively simple manyelectron systems – are characterized, as a rule, by a significant scatter. In addition, the canonical analytical formulas describing rаt within the framework of a hydrogen-like model with two effective interaction parameters (according to Slater) do not ultimately lead to adequate results in this set of elements. In this work, to correct the relationship rat = f (Еi1) related to the properties of the aggregate of alkaline elements, the publication of the effective Slater radii (reff) and Weber-Cromer orbital radii (rorb), and some results of later data are used. The effective principal quantum numbers n* for each of the AM (except for Li, for which it is assumed that n*=n=2) are estimated on the basis of the values of Ei1. A further step, by introducing n*, made it possible to use the criterion for optimizing the value of the effective radius r* and to correct the formula that determines its relationship with Ei1 in the form of a simple power function. At the same time, the radii Li, Na, and Fr have been refined towards some underestimation, compared with rorb. Arguments are presented in favor of the reliability of the proposed approach. It is shown that the obtained estimates of r* correlate better with the amplitudes of the solution of the wave equation covering all AMs than the known corresponding values of rorb and reff.

scholarly journals Phytochemical Analysis and Antiradical Properties of Sarcodon imbricatus (L.:Fr) Karsten

2008 ◽  
Vol 3 (11) ◽  
pp. 1934578X0800301 ◽  
Author(s):  
Maria Carla Marcotullio ◽  
Gildas Norbert Oball-Mond Mwankie ◽  
Lina Cossignani ◽  
Bruno Tirillini ◽  
Rita Pagiotti
Keyword(s):  
Antiradical Activity ◽  
Unsaturated Fatty Acids ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Nutritional Composition ◽  
Phytochemical Analysis ◽  
Ergosterol Peroxide ◽  
Antiradical Properties ◽  
Dpph Radical Scavenging ◽  
Good Food

The chemical composition of Sarcodon imbricatus (L.:Fr) Karsten (Hydnaceae) was evaluated to assess it as source of nutrients and nutraceuticals. The analyzed mushroom contains ergosterol and ergosterol peroxide. S. imbricatus methanolic extract showed a moderate antiradical activity (measured by DPPH radical scavenging activity). The combination of bioactive compounds and rich nutritional composition (high contents in protein, low content in fat, and its content of unsaturated fatty acids) makes the mushroom a good food.

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