Wyniki wyszukiwania - Biblioteka Nauki

1

Comparison of chemical composition and biological activities of Seseli rigidum fruit essential oils from Serbia

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Ilić M. D. , Jovanović V. P. S. , Mitić V. D. , Jovanović O. P. , Mihajilov-Krstev T. M. , Marković M. S. , Stojanović G. S.

Open Chemistry

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2015

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tom 13

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nr 1

EN

Plants from genus Seseli, have been widely used in European traditional medicine, exhibiting antibacterial, antifungal, insect repellent, emmenogogue, antiflatulence, anti-inflammatory, antinociceptive, anti-tumor, antirheumatic activities and protective effect on human lymphocytes DNA. They usually grow on mountain rocky terrains. Part of their habitat on Vidlic Mountain, located in South-east Serbia, was struck with a large wildfire. Seseli rigidum fruit essential oils (from post fire and control areas) compositions were analyzed by GC and GC-MS, identifying monoterpenes α-pinene and sabinene as most abundant. Statistical tests showed a non-significant difference in chemical composition of these two oils, but a significant difference in comparison with the herb from a geographically different origin. Antimicrobial tests showed strong activities of the oils against tested bacteria, thus confirming its administration in various inflammation processes as a quite effective remedy. Applying DPPH. and ABTS+. radical scavenging and total reducing Fe(III) to Fe(II) power assays, antioxidant characteristics of both studied essential oils were estimated as weak, though of close values. Seseli rigidum fruit essential oil was proven as a potent inhibitor of human and horse serum cholinesterase, recognizing its possible application as neural protective agent

2

Antioxidant radical scavenging capacity and total carotenoid content of narrow-clawed crayfish (Pontastacus leptodactylus, Eschscholtz, 1823) in Atikhisar Reservoir (Çanakkale, Türkiye)

100%

Acarlı S. , Kızılkaya B. , Vural P. , Barber S. , Kale S. , Acarlı D.

Oceanological and Hydrobiological Studies

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2023

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tom Vol. 52, No. 4

471--483

EN

n this study, antioxidant radical scavenging capacity and total carotenoid content in the meat and shells of Pontastacus leptodactylus were investigated. Concerning the antioxidant scavenging effect, the highest IC50 values were found to be 388.77 mg g-1 and 155.53 mg g-1 for females and males in July and March, respectively. The mean IC50 values of the meat were calculated as 239.83 mg g-1 and 105.21 mg g-1 for females and males, respectively. The mean total carotenoid content in the meat was found to be 14.35 and 12.78 μg g-1 for females and males, respectively. The results indicated that crayfish meat had antioxidant radical scavenging capacity and was rich in carotenoid content.

3

Przeciwutleniacze w technologii elastomerów

100%

Masek A. , Zaborski M.

Przetwórstwo Tworzyw

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2011

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tom [R.] 17, nr 5

344-346

PL

W celu ochrony wyrobów gumowych dodaje się na etapie przetwórstwa substancje przeciwstarzeniowe. Obecnie na skalę przemysłową stosuje się aminy aromatyczne, syntetyczne polifenole. Jednak współczesne trendy narzucają pewne normy zgodne z etyką ekologiczną. Zatem wydaje się, że należy poszukiwać nowych naturalnych przeciwutleniaczy, w pełni przyjaznych dla środowiska naturalnego. Niewątpliwie w taką grupę wpisują się naturalne polifenole syntezowane przez rośliny. Zaproponowane przez nas antyoksydanty mogą być ciekawą alternatywą dla przemysłu.

EN

In the objective of protection of rubber products at the stage of the processing substances are being added antioxidants. At present on an industrial scale an aromatic amine and synthetic polyphenols are applied. However contemporary trends are imposing certain norms in accordance with environmental ethics. And so it seems that one should discovery new natural and ecofriendly antiageing substances. Undoubtedly natural polyphenols are becoming part of such a group synthesize through plants. Antioxidants offered by us can be an interesting alternative to the industry.

4

Can angiotensin-converting enzyme inhibitors interfere with the free radicals? Measurement of antioxidant capacity using DPPH radical reduction examined by UV-VIS method

100%

Ramos P. , Juszczak A. , Szczołko W. , Pilawa B. , Stanisz B. J.

Acta Poloniae Pharmaceutica - Drug Research

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2019

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tom 76

|

nr 2

233-239

EN

A negative impact of radicals on human’s health is responsible for growing research interest in antioxidant properties of substances, which protect organisms from the damaging influence of these reactive species. Angiotensin-converting enzyme inhibitors (ACE-I) are the most popular drugs used in cardiovascular diseases. There are a lot of clinical reports that ACE-I have antioxidant properties, due to the fact, that prolonged use improves conditions of patients with neurodegenerative disorders and slow inflammatory processes. The paper shows the antioxidant properties of a selected ACE-I: cilazapril, ramipril, imidapril, lisinopril, perindopril, and quinapril. Among numerous methods for antioxidant activity estimation, DPPH reduction is the most popular and commonly used one due to its ease, speed, sensitivity and the usage of stable radicals. UV-Vis spectrophotometry was used to examine interactions of chosen ACE-I with model-free radicals. Absorption of UV-Vis spectra of DPPH (reference), and DPPH interacting with the tested ACE-I were compared. For all tested ACE-I kinetics of their interaction with DPPH, up to 30 minutes, were obtained. The strongest interaction with DPPH was observed for imidapril and cilazapril and the lowest interaction for lisinopril. Studies have shown usefulness UV-Vis spectrophotometry for obtaining information on interactions of ACE-I with model-free radicals.

5

Phytoconstitution and Antioxidant Activity of the Ethanolic Extract of an Antimalarial Herbal Mixture

100%

Odokwo E. O. , Onifade M. S.

World News of Natural Sciences

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2024

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tom 54

38-44

EN

The phytoconstitution and antioxidant profiling of mixture of herbs used in the treatment of malaria has been carried out. Herbs used as alternative medicines in the local treatment of malaria were collected from a herbal vendor in Ibadan. The herbal materials were extracted using absolute ethanol and the crude extract, EEA subjected to qualitative phytochemical screening and 2,2-diphenyl-1-picrylhydrazyl (DPPH) standard procedures. The presence of alkaloids, saponins, tannins, terpeniods, flavonoids and phenols were identified. EEA was found to exhibit antioxidant activity in the dose range of 25-400 μgml-1. The significant presence of major series of phytochemicals has justified the associated antimalarial ethnomedicinal claim. Thus, the present study has established the phytoconstitution and antioxidant activity of an antimalaria herbal mixture.

6

QSAR modeling of antiradical and antioxidant activities of flavonoids using electrotopological state (E-State) atom parameters

100%

Ray S. , Sengupta C. , Roy K.

Open Chemistry

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2007

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tom 5

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nr 4

1094-1113

EN

In the present paper QSAR modeling using electrotopological state atom (E-state) parameters has been attempted to determine the antiradical and the antioxidant activities of flavonoids in two model systems reported by Burda et al. (2001). The antiradical property of a methanolic solution of 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and the antioxidant activity of flavonoids in a β-carotenelinoleic acid were the two model systems studied. Different statistical tools used in this communication are stepwise regression analysis, multiple linear regressions with factor analysis as the preprocessing step for variable selection (FA-MLR) and partial least squares analysis (PLS). In both the activities the best equation is obtained from stepwise regression analysis, considering, both equation statistics and predictive ability (antiradical activity: R 2 = 0.927, Q2 = 0.871 and antioxidant activity: R 2 = 0.901, Q2 = 0.841). [...]

7

Antioxidant effects of carotenoids in a model pigment-protein complex

100%

Fiedor J. , Sulikowska A. , Orzechowska A. , Fiedor L. , Burda K.

Acta Biochimica Polonica

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2012

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tom 59

|

nr 1

61-64

EN

The effect of carotenoids on stability of model photosynthetic pigment-protein complexes subjected to chemical oxidation with hydrogen peroxide or potassium ferricyanide was investigated. The oxidation of carotenoid-less and carotenoid-containing complexes was conducted in the presence or absence of ascorbic acid. The progress of the reactions was monitored by use of absorption and fluorescence spectroscopy. Our results show that carotenoids may significantly enhance the stability of photosynthetic complexes against oxidation and their protective (antioxidant) effect depends on the type of the oxidant.

8

Simultaneous reverse-phase HPLC determination of major antioxidant phenolics in Commelina benghalensis L. tubers

100%

Misra A. , Srivastava A. , Srivastava S. , Rawat A. K. S.

Acta Chromatographica

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2016

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tom Vol. 28, no. 4

541--554

EN

Commelina benghalensis (Commelinaceae) is widely used as traditional and folklore medicine in India. In the present study, a reverse-phase high-performance liquid chromatography—photodiode array detection (RP-HPLC—PDA) method was developed for the separation, identification, and quantification of bioactive phenolics. Antioxidant potential was also accessed to validate the presence of identified markers. Method was developed on C18 column with 1% formic acid (in water) and acetonitrile as solvent system, and data acquisitions were achieved at wavelength of 285 nm. The developed method was also validated for accuracy, precision, robustness, limit of detection and quantification (LOD and LOQ), repeatability, and recovery according to International Conference on Harmonization (ICH) guidelines. In this method, five phenolics, viz., protocatechuic acid (0.033%), vanillic acid (0.262%), ferulic acid (0.365%), apigenin (0.126%), and kaempferol (0.544%), were quantified in linearity range of 0.2–1.0 μg with correlation coefficient of more than 0.9949. Relative standard deviation (RSD) (%), LOD, LOQ, and recovery (%) are within the acceptable limit. Besides that, methanolic extract shows the inhibition (%) range from 24.45 to 68.75% at 0.02–0.12 mg Ml-1. IC50 of extract was observed at 46.75 μg Ml-1, suggesting the promising activity in methanol extract. Hence, the proposed method for simultaneous quantification of five bioactive phenolics in the tuber of C. benghalensis using HPLC–PDA detection under the specified conditions is specific and accurate, and validation proves its selectivity and reproducibility.

9

Screening of active components as scavenger of radical from perennial fujimoto bean (Hyacinth Bean) whole herb by HPLC-MS coupled radical reaction

100%

Shi G. F. , Wang Z. J. , Wang G. Y. , Yao R. X. , Chen F. W. , Shi Z. R.

Acta Chromatographica

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2016

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tom Vol. 28, no. 1

19--31

EN

High-performance liquid chromatography-mass spectrometry (HPLC-MS) method coupled with radical reaction for screening active ingredients from perennial fujimoto bean whole herb was established. The active ingredients, present in perennial fujimoto bean whole herb, possess scavenging effects towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, superoxide, peroxy radical, and hydroxyl radical. The radical scavenging abilities of these active ingredients were evaluated based on the relative peak areas in the HPLC chromatogram. The results indicate that potent antioxidants are present in the anhydrous methanol extract of perennial fujimoto bean whole herb. Based on HPLC-MS analysis, it was found that the scavenging ability can be mostly attributed to the presence of three compounds: cyanidin-3-o-β-d-glucopyranoside, troxerutin, and rutin. The structures were identified based on the MS and nuclear magnetic resonance (NMR) data. Free radical scavenging activity decreased in the following order: troxerutin > rutin > cyanidin-3-o-β-d-glucopyranoside.

10

The construction of coenzyme Q-containing vesicles

100%

Grzybek M. , Stebelska K. , Sikorski A. F.

Cellular and Molecular Biology Letters

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2002

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tom 07

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nr Suppl.

11

Coenzyme Q: a bioenergetic and antioxidant compound

100%

Lenaz G.

Polish Journal of Environmental Studies

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1999

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tom 08

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nr 5

12

Melatonin and its metabolites: new findings regarding their production and their radical scavenging actions

88%

Reiter R. J. , Tan D.-x. , Pilar Terron M. , Flores L. J. , Czarnocki Z.

Acta Biochimica Polonica

|

2007

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tom 54

|

nr 1

1-9

EN

This review summarizes some of the recent findings concerning the long-held tenet that the enzyme, N-acetyltransferase, which is involved in the production of N-acetylserotonin, the immediate precursor of melatonin, may in fact not always control the quantity of melatonin generated. New evidence from several different laboratories indicates that hydroxyindole-O-methyltransferase, which O-methylates N-acetylserotonin to melatonin may be rate-limiting in some cases. Also, the review makes the point that melatonin's actions are uncommonly widespread in organs due to the fact that it works via membrane receptors, nuclear receptors/binding sites and receptor-independent mechanisms, i.e., the direct scavenging of free radicals. Finally, the review briefly summarizes the actions of melatonin and its metabolites in the detoxification of oxygen and nitrogen-based free radicals and related non-radical products. Via these multiple processes, melatonin is capable of influencing the metabolism of every cell in the organism.

13

Antioxidant properties of fruits of raspberry and blackberry grown in central Europe

88%

Kostecka-Gugała A. , Ledwożyw-Smoleń I. , Augustynowicz J. , Wyżgolik G. , Kruczek M. , Kaszycki P.

Open Chemistry

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2015

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tom 13

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nr 1

EN

Fruits of several, mainly Polish cultivars of floricane- and primocane-fruiting red raspberry (Rubus idaeus), black raspberry (Rubus occidentalis) and blackberry (Rubus fruticosus), grown in central Europe during two successive vegetation periods, were investigated. The content of phenolic compounds, including anthocyanins, as well as antioxidant properties of fruit extracts were analysed. A number of methods were employed: ferric ion reducing antioxidant power (FRAP), cupric ion reducing antioxidant capacity (CUPRAC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity involving both colorimetric and EPR spectrometric measurements. From among all the tested fruits black raspberries had the largest antioxidant capacity as verified by all methods used in this study. These berries were also the most abundant in phenolic and anthocyanin compounds. Blackberries were characterised by larger antioxidant capacity than red raspberry fruits which were accompanied by higher content of total phenolics and anthocyanins. Berries of primocane-fruiting cultivars, often used for intensive agricultural production, generally did not differ in the total phenolic and anthocyanin content as well as in the antioxidant capacity as compared to the traditional, floricane-fruiting ones. The research contributes to deep characterisation of central European berry fruits which due to their high content and large diversity of health-beneficial compounds are classified as natural functional food.

14

Lycopene as a guardian of redox signalling

88%

Palozza P. , Catalano A. , Simone R. , Cittadini A.

Acta Biochimica Polonica

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2012

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tom 59

|

nr 1

21-25

EN

It has been suggested that lycopene, the major carotenoid found in tomato, exhibits health-beneficial effects by virtue of its antioxidant activity. However, recent literature suggests that lycopene can actually "perform" roles independent of such capacity and involving a direct modulation of redox signalling. Reactive oxygen species are known to act as second messengers in the modulation of cellular signalling leading to gene expression changes and pharmacological responses. Lycopene may control redox-sensitive molecular targets, affecting enzyme activities and expressions and modulating the activation of MAPKs and transcription factors, such as NF-κB and AP-1, Nrf2.

15

Some bioactive properties of Acacia dealbata extracts and their potential utilization in wood protection

88%

Yildiz S. , Gürgen A. , Can Z. , Tabbouche S. A. , Kiliç A. O.

Drewno : prace naukowe, doniesienia, komunikaty

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2018

|

tom vol. 61, nr 202

81--97

EN

A study was made of the potential use of Acacia dealbata wood extracts as bioprotective agents. Initially, extracts were obtained from Acacia dealbata sapwood, heartwood and bark, and their antioxidant, antimicrobial and anti-quorum sensing activities were determined. Next, the decay resistance of Scots pine wood samples impregnated with these extracts was examined against the brown rot fungus, Coniophora puteana. The impregnation procedure was performed according to the ASTM D (1413) standard test method at two different concentrations, 3% and 5% by weight, using hot water and methanol as extraction solvents. The strongest antioxidant, antimicrobial and anti-quorum sensing activities were those of the bark extract. Hot water extraction led to lower performance than methanol extraction. According to EN 113 testing methods, the highest level of preservative effect against wood-decaying fungi was observed in the case of 5% methanol extract from the bark.

16

The antioxidant and antibacterial activities of the essential oils of Marrubium vulgare growing wild in Eastern Algeria

88%

Abadi A. , Abdellatif F.

International Letters of Chemistry, Physics and Astronomy

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2013

|

tom Vol. 10, iss. 2

159-166

EN

The chemical composition was analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The constituents were identified by their mass spectra and Kovats’ indices. Fivety (50) components in the oil of M. vulgare were identified. The results demonstrated that the major components of the essential oil were : 4,8,12,16-Tetramethyl heptadecan-4-olid (16.97 %), Germacrene D-4-ol (9.61 %), α- pinéne (9.37 %), Phytol (4.87 %), Dehydro-sabina ketone (4.12 %), Piperitone (3.27 %), δ-Cadinene (3.13 %), 1-Octen-3-ol (2.35 %) and Benzaldehyde (2.31 %). The antioxidant activity of the oils was assessed by measurement of metal chelating activity, the reductive potential, the free radical scavenging (DPPH) assay. The antioxidant activity was compared with that of synthetic antioxidants: butylated hydroxyanisole (BHT) , and the essential oils . The results showed as the Essential oil of M vulgare was evaluated for its antibacterial activities against Gram-positive and Gram negative pathogenic bacteria: Listeria monocytogene, Pseudomonas aeruginosa , Agrobacterium tumefaciens and Salmonella enterica.

17

Distilled Spirit Extraction of Phenolic Antioxidants from Fruit and Vegetable Residues

88%

Ortinero C. V. , Rafael R. R. , Rayos C. E. R. , Bautista K. D. A. , Feliciano M. A. M. , Natividad L. R. , Natividad G. M.

Journal of Ecological Engineering

|

2021

|

tom Vol. 22, nr 1

125--131

EN

There is a growing interest in natural antioxidants due to their potential in improving the quality of food and cosmetic products and their health-promoting properties. Distilled spirits contain high amount of ethanol and may be an alternative to the food-grade solvents, while agricultural by-products contain phenolic substances that may have antioxidant properties. This study was therefore conducted to find out if gin, vodka, and tequila flavored spirit, alcoholic beverages with about 40% ethanol, can extract the phenolic compounds from agricultural by-products, and to determine if the extracts possess the antioxidant activity. Peels of ripe banana (Musa acuminata), ripe mango (Mangifera indica), calamansi (Citrofortunella microcarpa), squash (Cucurbita maxima), ripe pineapple (Ananas comosus), purple yam (Dioscorea alata), and sweet potato (Ipomea batatas) were collected, dried, and ground. The phenolic substances in the plant materials were extracted with alcoholic beverages or 40% ethanol. The total phenolic content (TPC) of the extracts was determined by means of UV-Vis spectroscopy using Folin-Ciocalteau reagent and gallic acid as reference compound. The antioxidant activity of the extracts was evaluated through the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. Butylated hydroxyanisole (BHA) served as positive control in the DPPH assay. Non-linear regression was applied to the DPPH assay data to estimate the values of median effective concentration (EC50). All three alcoholic beverages were able to extract the phenolic materials from the plant samples. However, the ability of vodka and gin to extract the phenolic substances was either statistically comparable or better than 40% ethanol. The results of the DPPH scavenging assay showed that the M. indica peel had the strongest activity, while C. microcarpa had the weakest scavenging activity. At 1000-ppm level, the antioxidant activity of the M. indica peel was comparable with that of BHA, regardless of the solvent used for extraction. Therefore, the M. indica peel can be a source of natural antioxidants and potential substitute to synthetic antioxidants. Both gin and vodka can be used as a substitute for food-compatible solvents.

18

Protective effects of cassia seed ethanol extract against carbon tetrachloride-induced liver injury in mice

88%

Xie Q. , Guo F.-F. , Zhou W.

Acta Biochimica Polonica

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2012

|

tom 59

|

nr 2

265-270

EN

Oxidative stress has been recognized as a critical pathogenetic mechanism for the initiation and the progression of hepatic injury in a variety of liver disorders. Antioxidants, including many natural compounds or extracts, have been used to cope with liver disorders. The present study was designed to investigate the hepatoprotective effects of cassia seed ethanol extract (CSE) in carbon tetrachloride (CCl4)-induced liver injury in mice. The animals were pre-treated with different doses of CSE (0.5, 1.0, 2.0 g/kg body weight) or distilled water for 5 days, then were injected intraperitoneally with CCl4 (0.1% in corn oil, v/v, 20 ml/kg body weight), and sacrificed at 16 hours after CCl4 exposure. The serum aminotransferase activities, histopathological changes, hepatic and mitochondrial antioxidant indexes, and cytochrome P450 2E1 (CYP2E1) activities were examined. Consistent with previous studies, acute CCl4 administration caused great lesion to the liver, shown by the elevation of the serum aminotransferase activities, mitochondria membrane permeability transition (MPT), and the ballooning degeneration of hepatocytes. However, these adverse effects were all significantly inhibited by CSE pretreatment. CCl4-induced decrease of the CYP2E1 activity was dose-dependently inhibited by CSE pretreatment. Furthermore, CSE dramatically decreased the hepatic and mitochondrial malondialdehyde (MDA) levels, increased the hepatic and mitochondrial glutathione (GSH) levels, and restored the activities of superoxide dismutase (SOD), glutathione reductase (GR), and glutathione S-transferase (GST). These results suggested that CSE could protect mice against CCl4-induced liver injury via enhancement of the antioxidant capacity.

19

Antioxidant properties of Artemisia absinthium accelerate healing of experimental Achilles tendon injury in rabbits

88%

Hoseinian A. , Moslemi H. R. , Sedaghat R.

Herba Polonica

|

2018

|

tom 64

|

nr 1

EN

Delayed tendon healing is still found to be among the complications that occur most often after tendon repair. The role of local injection of Artemisia absinthium was evaluated in healing of experimental Achilles tendon injury in rabbits. In nine adult New Zealand rabbits a partial thickness tenotomy was created on both hindlimbs. A. absinthium extract and normal saline were respectively injected daily to treatment and control groups for three days. On the day 7 after injury, the tendon sections showed that healing rate in A. absinthium treated group was higher than that in control group. Furthermore, at days 14 and 28, comparison between A. absinthium treated group and control group demonstrated that A. absinthium increased the healing rate but with no significance. Results of this study have showed that application of A. absinthium extract can improve healing process of damaged Achilles tendon.

PL

Powolne gojenie jest jedną z komplikacji pojawiających się najczęściej po operacji odbudowy ścięgna. Badano wpływ miejscowego podania Artemisia absinthium w iniekcji na gojenie doświadczalnego uszkodzenia ścięgna Achillesa u królików. U dziewięciu dorosłych królików nowozelandzkich przeprowadzono częściową tenotomię ścięgien obu kończyn tylnych. Następnie podawano w iniekcji wyciąg z A. absinthium lub sól fizjologiczną odpowiednio w grupie doświadczalnej i w grupie kontrolnej przez trzy dni.Siódmego dnia po uszkodzeniu okazało się, że tempo gojenia w grupie leczonej wyciągiem z A. absinthium było wyższe niż w grupie kontrolnej. Co więcej, porównanie przeprowadzone 14. i 28. dnia wykazało, że podanie A. absinthium przyspieszyło gojenie, ale nieistotnie.Wyniki tego badania pokazują, że podanie wyciągu z A. absinthium może przyspieszyć process gojenia uszkodzonego ścięgna Achillesa.

20

TLC-DPPH• activity-guided separation and LC-DAD-MS identification of antioxidant compounds from Mutellina purpurea L. herb

88%

Sieniawska E. , Baj T. , Dudka J. , Mroczek T. , Głowniak K.

Acta Chromatographica

|

2016

|

tom Vol. 28, no. 1

51--58

EN

Many phytochemical investigations have been focused recently on the antioxidant activity of herbal extracts which can be used in phytotherapy. The previous study revealed antioxidative properties of Mutellina purpurea extract, but the constituents responsible for this action were not described yet. The aim of this study was activityguided separation and identification of antioxidant compounds from M. purpurea herb. Thin-layer chromatography-2,2-diphenyl-1-picrylhydrazyl (TLC-DPPH•) assay was used to detect compounds of interest; liquid chromatography-diode array detection-mass spectrometry (LC-DAD-MS) analysis allowed to identify antioxidants. The active fractions analyzed with LC-DAD-MS contained as a main compound chlorogenic acid accompanied with p-coumaric acid, ferulic acid, three dicaffeoylquinic acids, and caffeoylferuloylquinic acid. The fast TLC-DPPH• assay with LC-DAD-MS identification enabled the accurate identification of antioxidants in M. purpurea herb, which was done for the first time.