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A series of 3-substituted and 3,5-disubstituted rhodanine-based derivatives were synthesized from 3-aminorhodanine and examined for α-amylase inhibitory, DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activities in vitro. These derivatives displayed significant α-amylase inhibitory potential with IC50 values of 11.01-56.04 µM in comparison to standard acarbose (IC50 = 9.08 ± 0.07 µM). Especially, compounds 7 (IC50 = 11.01 ± 0.07 µM) and 8 (IC50 = 12.01 ± 0.07 µM) showed highest α-amylase inhibitory activities among the whole series. In addition to α-amylase inhibitory activity, all compounds also demonstrated significant scavenging activities against DPPH and ABTS radicals, with IC50 values ranging from 12.24 to 57.33 and 13.29-59.09 µM, respectively, as compared to the standard ascorbic acid (IC50 = 15.08 ± 0.03 µM for DPPH; IC50 = 16.09 ± 0.17 µM for ABTS). These findings reveal that the nature and position of the substituents on the phenyl ring(s) are crucial for variation in the activities. The structure-activity relationship (SAR) revealed that the compounds bearing an electron-withdrawing group (EWG) at para substitution possessed the highest activity. In kinetic studies, only the km value was changed, with no observed changes in Vmax, indicating a competitive inhibition. Molecular docking studies revealed important interactions between compounds and the α-amylase active pocket. Further advanced research needs to perform on the identified compounds in order to obtain potential antidiabetic agents.
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Coumarins represent a diverse class of natural compounds whose importance in pharmaceutical and agri-food sectors has motivated multiple novel synthetic derivatives with broad applicability. The phenolic moiety in 4-hydroxycoumarins underscores their potential to modulate the equilibrium between free radicals and antioxidant species within biological systems. The aim of this work was to assess the antioxidant activity of 18 4-hydroxycoumarin coumarin derivatives, six of which are commercially available and the other 12 were synthesized and chemically characterized and described herein. The 4-hydroxycoumarins were prepared by a two steps synthetic strategy with satisfactory yields. Their antioxidant potential was evaluated through three in vitro methods, two free radical-scavenging assays (DPPH⢠and ABTSâ¢+) and a metal chelating activity assay. Six synthetic coumarins (4a, 4g, 4h, 4i, 4k, 4l) had a scavenging capacity of DPPH⢠higher than butylated hydroxytoluene (BHT) (IC50 = 0.58 mmol/L) and compound 4a (4-hydroxy-6-methoxy-2 H-chromen-2-one) with an IC50 = 0.05 mmol/L outperformed both BHT and ascorbic acid (IC50 = 0.06 mmol/L). Nine hydroxycoumarins had a scavenging capacity against ABTSâ¢+ greater (C3, 4a, 4c) or comparable (C1, C2, C4, C6, 4g, 4l) to Trolox (IC50 = 34.34 µmol/L). Meanwhile, the set had a modest ferrous chelation capacity, but most of them (C2, C5, C6, 4a, 4b, 4h, 4i, 4j, 4k, 4l) reached up to more than 20% chelating ability percentage. Collectively, this research work provides valuable structural insights that may determine the scavenging and metal chelating activity of 4-hydroxycoumarins. Notably, substitutions at the C6 position appeared to enhance scavenging potential, while the introduction of electron-withdrawing groups showed promise in augmenting chelation efficiency.
Assuntos
4-Hidroxicumarinas , Antioxidantes , Sequestradores de Radicais Livres , 4-Hidroxicumarinas/química , 4-Hidroxicumarinas/farmacologia , 4-Hidroxicumarinas/síntese química , Antioxidantes/síntese química , Antioxidantes/farmacologia , Antioxidantes/química , Sequestradores de Radicais Livres/síntese química , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/química , Picratos/química , Quelantes/química , Quelantes/farmacologia , Quelantes/síntese química , Compostos de Bifenilo/química , Ácidos Sulfônicos/química , Relação Estrutura-Atividade , BenzotiazóisRESUMO
The persistence and ubiquity of polycyclic aromatic hydrocarbons (PAHs) in the environment necessitate effective remediation strategies. Hence, this study investigated the potential of purified Laccases, TlFLU1L and TpFLU12L, from two indigenous fungi Trichoderma lixii FLU1 (TlFLU1) and Talaromyces pinophilus FLU12 (TpFLU12), respectively for the oxidation and detoxification of anthracene. Anthracene was degraded with vmax values of 3.51 ± 0.06 mg/L/h and 3.44 ± 0.06 mg/L/h, and Km values of 173.2 ± 0.06 mg/L and 73.3 ± 0.07 mg/L by TlFLU1L and TpFLU12L, respectively. The addition of a mediator compound 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) to the reaction system significantly increased the degradation of anthracene, with up to a 2.9-fold increase in vmax value and up to threefold decrease in Km values of TlFLU1L and TpFLU12L. The GC-MS analysis of the metabolites suggests that anthracene degradation follows one new pathway unique to the ABTS system-hydroxylation and carboxylation of C-1 and C-2 position of anthracene to form 3-hydroxy-2-naphthoic acid, before undergoing dioxygenation and side chain removal to form chromone which was later converted into benzoic acid and CO2. This pathway contrasts with the common dioxygenation route observed in the free Laccase system, which is observed in the second degradation pathways. Furthermore, toxicity tests using V. parahaemolyticus and HT-22 cells, respectively, demonstrated the non-toxic nature of Laccase-ABTS-mediated metabolites. Intriguingly, analysis of the expression level of Alzheimer's related genes in HT-22 cells exposed to degradation products revealed no induction of neurotoxicity unlike untreated cells. These findings propose a paradigm shift for bioremediation by highlighting the Laccase-ABTS system as a promising green technology due to its efficiency with the discovery of a potentially less harmful degradation pathway, and the production of non-toxic metabolites.
Assuntos
Antracenos , Biodegradação Ambiental , Lacase , Talaromyces , Lacase/metabolismo , Antracenos/metabolismo , Talaromyces/enzimologia , Trichoderma/enzimologia , Animais , Proteínas Fúngicas/metabolismoRESUMO
The effect of La, Ce, Pr and Nd ions on four Ln(ligand)3 complexes and at three DFT levels of calculation was analyzed. Four ligands were chosen, three of which were based on the 1,2,3-triazole ring. The DFT methods used were B3LYP, CAM-B3LYP and M06-2X. The relationships established were between the geometric parameters, atomic charges, HOMO-LUMO energies and other molecular properties. These comparisons and trends will facilitate the synthesis of new complexes by selecting the ligand and lanthanide ion best suited to the desired property of the complex. The experimental IR and Raman spectra of Ln(2b')3 complexes where Ln = La, Ce, Pr, Nd, Sm, Gd, Dy, Ho and Er ions have been recorded and compared to know the effect of the lanthanide ion on the complex. The hydration in these complexes was also analyzed. Additionally, the effect of the type of coordination center on the ability of an Ln(ligand)3 complex to participate in electron exchange and hydrogen transfer was investigated using two in vitro model systems-DPPH and ABTS.
Assuntos
Elementos da Série dos Lantanídeos , Triazóis , Triazóis/química , Triazóis/farmacologia , Elementos da Série dos Lantanídeos/química , Ligantes , Íons/química , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Análise Espectral Raman , Modelos MolecularesRESUMO
In this study, the phytochemical composition, in vitro antioxidant, and anti-inflammatory effects of the aqueous and 60% ethanolic (EtOH) extracts of Santolina rosmarinifolia leaf, flower, and root were examined. The antioxidant activity of S. rosmarinifolia extracts was determined by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays. The total phenolic content (TPC) of the extracts was measured by the Folin-Ciocalteu assay. The anti-inflammatory effect of the extracts was monitored by the Griess assay. The chemical composition of S. rosmarinifolia extracts was analysed using the LC-MS technique. According to our findings, 60% EtOH leaf extracts showed the highest Trolox equivalent antioxidant capacity (TEAC) values in both ABTS (8.39 ± 0.43 µM) and DPPH (6.71 ± 0.03 µM) antioxidant activity assays. The TPC values of the samples were in good correspondence with the antioxidant activity measurements and showed the highest gallic acid equivalent value (130.17 ± 0.01 µg/mL) in 60% EtOH leaf extracts. In addition, the 60% EtOH extracts of the leaves were revealed to possess the highest anti-inflammatory effect. The LC-MS analysis of S. rosmarinifolia extracts proved the presence of ascorbic acid, catalpol, chrysin, epigallocatechin, geraniol, isoquercitrin, and theanine, among others, for the first time. However, additional studies are needed to investigate the direct relationship between the chemical composition and physiological effects of the herb. The 60% EtOH extracts of S. rosmarinifolia leaves are potential new sources of natural antioxidants and anti-inflammatory molecules in the production of novel nutraceutical products.
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Antioxidantes , Asteraceae , Benzotiazóis , Antioxidantes/farmacologia , Ácido Ascórbico , Ácidos Sulfônicos , Anti-Inflamatórios/farmacologiaRESUMO
This work developed a rapid colorimetric method for nitrite detection in meat products. The detection was based on the reaction of nitrite with 60 mM HCl to produce radicals which further oxidized ABTS (50 µM) to form a water-soluble blue-green product (ABTSâ¢+). The absorbance was measured at a maximum absorption wavelength of 412.5 nm. Parameters such as concentration of HCl, concentration of ABTS and reaction time were evaluated. The absorbance was linearly proportional to the concentration of nitrite (0.1-20 µM) with the limit of detection of 0.34 µM. The proposed method was a time-saving assay since it required only 2 min to complete one measurement. There was no effect of the interference produced by other ions. The assay was robust with 2.5%RSD (n = 50). In meat product samples, high accuracy was observed with the recoveries between 100 ± 2.2% and 105 ± 3.7%. The amount of nitrite in meat products detected by the ABTS method was found in the range of 5.41 - 7.62 mg/kg. The conventional Griess method was applied to determine nitrite in the same meat products. There was no statistically significant difference between the two methods (P = 0.05).
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Colorimetria , Produtos da Carne , Colorimetria/métodos , Nitritos , Ácidos SulfônicosRESUMO
In order to characterize and identify the chemical components in different parts of Artemisia argyi(roots, stems, leaves, and seeds), compounds with antioxidant activity were screened. In this study, ultra-performance liquid chromatography-2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt-quadrupole time-of-flight-tandem mass spectrometry(UPLC-ABTS-Q-TOF-MS) was used as an online combination technique. Poroshell 120 SB-Aq(3.0 mm×150 mm, 2.7 µm) was used as the column, and acetonitrile(A)-0.2% formic acid water(B) was adopted as the mobile phase to perform gradient elution and was scanned in positive and negative ion modes. MassLynx software was utilized, and combined with reference substances and related literature, the chemical components of different parts of A. argyi were identified and compared. The antioxidant active components were detected by using the online detection system, and the antioxidant activities of active components of different parts of A. argyi were compared and evaluated by scavenging efficiency. As a result, a total of 87 compounds were identified from extracts of different parts of A. argyi, and 38, 72, 85, and 33 components were identified from roots, stems, leaves, and seeds. 22 compounds with antioxidant activity were screened, and 14, 17, 20, and 11 compounds with antioxidant activity were identified from roots, stems, leaves, and seeds. The results show that there are certain differences in chemical components and antioxidant components of different parts of A. argyi, which provides data support for the resource utilization and further research and development of A. argyi.
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Antioxidantes , Artemisia , Artemisia/química , Antioxidantes/química , Antioxidantes/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Medicamentos de Ervas Chinesas/química , Folhas de Planta/química , Espectrometria de Massas/métodos , Ácidos Sulfônicos/química , Sementes/química , Benzotiazóis/química , Raízes de Plantas/químicaRESUMO
The activation of peroxydisulfate (PDS) by organic compounds has attracted increasing attention. However, some inherent drawbacks including quick activator decomposition and poor anti-interference capacity limited the application of organic compound-activated PDS. It was interestingly found that 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonate) (ABTS) could act as both activator and electron shuttle for PDS activation to enhance diclofenac (DCF) degradation over a pH range of 2.0-11.0. Multiple reactive species of ABTSâ¢+, â¢OH, and SO4â¢- were generated in the PDS/ABTS system, while only ABTSâ¢+ and â¢OH directly contributed to DCF degradation. ABTSâ¢+, generated via the reactions of ABTS with PDS, SO4â¢-, and â¢OH, was the dominant reactive species of DCF degradation. No significant decomposition of ABTS was observed in the PDS/ABTS system, and ABTS acted as both activator and electron shuttle. Four possible degradation pathways of DCF were proposed, and the toxicity of DCF decreased after treatment with the PDS/ABTS system. The PDS/ABTS system had good anti-interference capacity to common natural water constituents. Additionally, ABTS was encapsulated into cellulose to obtain ABTS@Ce beads, and the PDS/ABTS@Ce system possessed excellent performance on DCF degradation. This study proposes a new perspective to reconsider the mechanism of activating PDS with organic compounds and highlights the considerable contribution of organic radicals on contaminant removal.
Assuntos
Diclofenaco , Poluentes Químicos da Água , Oxirredução , Elétrons , Poluentes Químicos da Água/análise , Compostos OrgânicosRESUMO
Lactoperoxidase was previously used as a model enzyme to test the inhibitory activity of selenium analogs of anti-thyroid drugs with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) as a substrate. Peroxidases oxidize ABTS to a metastable radical ABTSâ¢+, which is readily reduced by many antioxidants, including thiol-containing compounds, and it has been used for decades to measure antioxidant activity in biological samples. We showed that anti-thyroid drugs 6-n-propyl-2-thiouracil, methimazole, and selenium analogs of methimazole also reduced it rapidly. This reaction may explain the anti-thyroid action of many other compounds, particularly natural antioxidants, which may reduce the oxidized form of iodine and/or tyrosyl radicals generated by thyroid peroxidase thus decreasing the production of thyroid hormones. However, influence of selenium analogs of methimazole on the rate of hydrogen peroxide consumption during oxidation of ABTS by lactoperoxidase was moderate. Direct hydrogen peroxide reduction, proposed before as their mechanism of action, cannot therefore account for the observed inhibitory effects. 1-Methylimidazole-2-selone and its diselenide were oxidized by ABTSâ¢+ to relatively stable seleninic acid, which decomposed slowly to selenite and 1-methylimidazole. In contrast, oxidation of 1,3-dimethylimidazole-2-selone gave selenite and 1,3-dimethylimidazolium cation. Accumulation of the corresponding seleninic acid was not observed.
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Selênio , Antioxidantes/farmacologia , Cátions , Peróxido de Hidrogênio/química , Lactoperoxidase/metabolismo , Metimazol/farmacologia , Oxirredução , Ácido Selenioso , Selênio/química , Propiltiouracila/química , Propiltiouracila/farmacologiaRESUMO
Oxides of vanadium, titanium and graphitic carbon nitride (g-C3N4) are well known for their catalytic activities. In order to achieve synergic catalytic effects, a novel nanocomposite (NC) i.e. V2O5/TiO2/g-C3N4 has been synthesized by a very simple, ecofriendly and nonhazardous hydrothermal method. The fabricated NC was characterized employing UV-Visible, FTIR, SEM, and XRD techniques. UV-Visible and FTIR analysis indicated the formation of the nanocomposite and XRD analysis confirmed the association of V2O5 and TiO2 with g-C3N4 in nanocomposite. SEM study indicated the hetero-structure of NC having size ranging from 50 to 80 nm and it was found having hexagonal crystallite structure. The synthesized nanocomposite exhibited excellent scavenging of free radicals DPPHâ (91%) and ABTSâ+ (64%) that are responsible for the oxidation of biomolecules. Therefore, NC can be claimed having biomolecule oxidation protective potential. In addition, photocatalytic ability for the degradation of methylene blue (MB) and methyl orange (MO) was also achieved up to 94% and 89% respectively. The synthesized novel nanocomposite exhibited excellent potential to remove free radicals and dyes from aqueous medium which can be further used for the environmental remediation.
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Luz , Nanocompostos , Corantes , Nanocompostos/química , CatáliseRESUMO
A two-step reaction method was used to synthesize a series of rhodanine-based Schiff bases (2-33) that were characterized using spectroscopic techniques. All compounds were assessed for α-amylase inhibitory and radical scavenging (DPPH and ABTS) activities. In comparison to the standard acarbose (IC50 = 9.08 ± 0.07 µM), all compounds demonstrated good to moderate α-amylase inhibitory activity (IC50 = 10.91 ± 0.08-61.89 ± 0.102 µM). Compounds also demonstrated significantly higher DPPH (IC50 = 10.33 ± 0.02-96.65 ± 0.03 µM) and ABTS (IC50 = 12.01 ± 0.12-97.47 ± 0.13 µM) radical scavenging activities than ascorbic acid (DPPH, IC50 = 15.08 ± 0.03 µM; ABTS, IC50 = 16.09 ± 0.17 µM). The limited structure-activity relationship (SAR) suggests that the position and nature of the substituted groups on the phenyl ring have a vital role in varying inhibitory potential. Among the series, compounds with an electron-withdrawing group at the para position showed the highest potency. Kinetic studies revealed that the compounds followed a competitive mode of inhibition. Molecular docking results are found to agree with experimental findings, showing that compounds reside in the active pocket due to the main rhodanine moiety.
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Rodanina , Rodanina/farmacologia , Simulação de Acoplamento Molecular , Bases de Schiff/química , Cinética , Compostos de Bifenilo/química , Relação Estrutura-Atividade , alfa-Amilases/química , Estrutura MolecularRESUMO
An [Et3 NH][HSO4 ] ionic-liquid catalyzed, intermolecular C-N bond formation for 1,2-disubstituted benzimidazole synthesis was achieved by the reaction of OPD and substituted aldehydes at ambient reaction conditions. Operational simplicity, use of easily available substrate and reagents, good yields (74-95 %) in short reaction time (4-18â min), simple work-up, and column chromatographic free synthesis are the remarkable features of this new protocol. The applicability of [Et3 NH][HSO4 ] ionic-liquid as a green and inexpensive catalyst with good recyclability and compatibility with a broad range of functional group having heteroatom, electron-withdrawing, and electron-releasing groups manifested the sustainability, eco-friendliness, and efficiency of the present methodology. Moreover, the antioxidant studies of the synthesized compounds using DPPH and ABTS assays were appealing and several synthesized compounds showed significant antioxidant activity.
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The antioxidant activity and chemical stability of 6-amino-6-deoxy-L-ascorbic acid (D1) and N-methyl-6-amino-6-deoxy-L-ascorbic acid (D2) were examined with ABTS and DPPH assays and compared with the reference L-ascorbic acid (AA). In addition, the optimal storing conditions, as well as the pH at which the amino derivatives maintain stability, were determined using mass spectrometry. Comparable antioxidant activities were observed for NH-bioisosteres and AA. Moreover, D1 showed higher stability in an acidic medium than the parent AA. In addition, AA, D1, and D2 share the same docking profile, with wild-type human peroxiredoxin as a model system. Their docking scores are similar to those of dithiothreitol (DTT). This suggests a similar binding affinity to the human peroxiredoxin binding site.
Assuntos
Antioxidantes , Ácido Ascórbico , Humanos , Ácido Ascórbico/química , Simulação de Acoplamento MolecularRESUMO
The reaction of the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) free radical (ABTSâ) with proteins (bovine serum albumin, blood plasma, egg white, erythrocyte membranes, and Bacto Peptone) leads not only to a reduction of ABTSâ but also to the appearance of a purple color (absorption maximum at 550-560 nm). The aim of this study was to characterize the formation and explain the nature of the product responsible for the appearance of this color. The purple color co-precipitated with protein, and was diminished by reducing agents. A similar color was generated by tyrosine upon reaction with ABTSâ. The most feasible explanation for the color formation is the addiction of ABTSâ to proteins' tyrosine residues. The product formation was decreased by nitration of the bovine serum albumin (BSA) tyrosine residues. The formation of the purple product of tyrosine was optimal at pH 6.5. A decrease in pH induced a bathochromic shift of the spectra of the product. The product was not a free radical, as demonstrated by electrom paramagnetic resonance (EPR) spectroscopy. Another byproduct of the reaction of ABTSâ with tyrosine and proteins was dityrosine. These byproducts can contribute to the non-stoichiometry of the antioxidant assays with ABTSâ. The formation of the purple ABTS adduct may be a useful index of radical addition reactions of protein tyrosine residues.
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Soroalbumina Bovina , Tirosina , Oxirredução , Soroalbumina Bovina/metabolismo , Tirosina/metabolismo , Radicais Livres/metabolismoRESUMO
Vitamin K3 (menadione), classified as a pro-vitamin, is a synthetic form of the fat-soluble family of vitamin K compounds. The combination of the vitamin with other molecules sharing structural and/or functional similarities, such as naturally occurring polyphenols, vitamins, or biopolymers, could potentiate mutual improvement of their antioxidant activity. The aim of the present study was to evaluate the role and contribution of vitamin K3 to the in vitro radical scavenging capacity of double and triple combinations with the phytochemicals naringenin and lignin, as well as assess possible intermolecular interactions between the bioactive compounds. Comparative analyses of the DPPH and ABTS radical scavenging activity of the pure substances vitamin K3, naringenin, and lignin; the two-component systems lignin/vitamin K3 and vitamin K3/naringenin; and the triple combination vitamin K3/flavonoid/lignin were carried out. The experimental results demonstrated increased DPPH and ABTS activities of the vitamin in combination with lignin compared to those of the two pure substances, i.e., a synergistic effect was observed. The registered significant increases in the radical scavenging activity of the triple combination determined via both methods are indicative of a remarkable potentiation effect, i.e., higher antioxidant potential exceeding the additive activity of the three pure substances.
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Lignina , Vitamina K 3 , Vitamina K 3/farmacologia , Vitamina K , Antioxidantes/farmacologia , Vitaminas , Compostos Fitoquímicos/farmacologiaRESUMO
Nitroxides, stable synthetic free radicals, are promising antioxidants, showing many beneficial effects both at the cellular level and in animal studies. However, the cells are usually treated with high millimolar concentrations of nitroxides which are not relevant to the concentrations that could be attained in vivo. This paper aimed to examine the effects of low (≤10 µM) concentrations of three nitroxides, 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO), 4-hydroxy-TEMPO (TEMPOL) and 4-amino-TEMPO (TEMPAMINE), in pure chemical systems and on SH-SY5Y cells transfected with the human tau protein (TAU cells), a model of chronic cellular oxidative stress, and transfected with the empty plasmid (EP cells). All nitroxides were active in antioxidant-activity tests except for the 2,2'-azinobis-(3-ethylbenzthiazolin-6-sulfonate) radical (ABTSâ¢) decolorization assay and reduced Fe3+, inhibited autoxidation of adrenalin and pyrogallol and oxidation of dihydrorhodamine123 by 3-morpholino-sydnonimine SIN-1. TEMPO protected against fluorescein bleaching from hypochlorite, but TEMPAMINE enhanced the bleaching. Nitroxides showed no cytotoxicity and were reduced by the cells to non-paramagnetic derivatives. They decreased the level of reactive oxygen species, depleted glutathione, and increased mitochondrial-membrane potential in both types of cells, and increased lipid peroxidation in TAU cells. These results demonstrate that even at low micromolar concentrations nitroxides can affect the cellular redox equilibrium and other biochemical parameters.
Assuntos
Neuroblastoma , Proteínas tau , Animais , Humanos , Proteínas tau/genética , Óxidos de Nitrogênio/farmacologia , Antioxidantes/farmacologia , Óxidos N-Cíclicos/farmacologiaRESUMO
When the total phenolic content (TPC) and antioxidant activity of sea buckthorn juice were assayed by spectrophotometry, the reaction solutions were not clarified, so centrifugation or membrane treatment was needed before determination. In order to find a suitable method for determining TPC and antioxidant activity, the effects of centrifugation and nylon membrane treatment on the determination of TPC and antioxidant activity in sea buckthorn juice were studied. TPC was determined by the Folin-Ciocalteau method, and antioxidant activity was determined by DPPH, ABTS, and FRAP assays. For Treatment Method (C): the sample was centrifuged for 10 min at 10,000 rpm and the supernatant was taken for analysis. Method (CF): The sample was centrifuged for 10 min at 4000 rpm, filtered by Nylon 66 filtration membranes with pore size of 0.22 µm, and taken for analysis. Method (F): the sample was filtered by Nylon 66 filtration membranes with pore size of 0.22 µm and taken for analysis. Method (N): after the sample of ultrasonic extract solution reacted completely with the assay system, the reaction solution was filtered by Nylon 66 filtration membranes with pore size of 0.22 µm and colorimetric determination was performed. The results showed that centrifugation or transmembrane treatment could affect the determination of TPC and antioxidant activity of sea buckthorn juice. There was no significant difference (p > 0.05) between methods (CF) and (F), while there was a significant difference (p < 0.05) between methods (C) (F) (N) or (C) (CF) (N). The TPC and antioxidant activity of sea buckthorn juice determined by the four treatment methods showed the same trend with fermentation time, and the TPC and antioxidant activity showed a significant positive correlation (p < 0.05). The highest TPC or antioxidant activity measured by method (N) indicates that method (N) has the least loss of TPC or antioxidant activity, and it is recommended for sample assays.
Assuntos
Antioxidantes , Hippophae , Antioxidantes/farmacologia , Antioxidantes/análise , Polifenóis/farmacologia , Polifenóis/análise , Hippophae/química , Nylons , Fenóis/análise , Frutas/química , CentrifugaçãoRESUMO
High-performance liquid chromatography (HPLC) and high-performance thin-layer chromatography (HPTLC) coupled with radical scavenging assays, such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) can be both used for the detection of the antioxidants in plant extracts. In this study, the ethanolic (70% v/v) extracts from different morphological parts of Ligustrum vulgare collected at different stages of maturity were used as the source of antioxidants. The final identification of antioxidants was performed using high-resolution mass spectroscopy (HRMS). As a result, 19 compounds with antioxidant properties detected with HPLC-ABTS assay and 10 compounds detected with HPTLC-DPPH/ABTS assay were identified, mostly from the group of iridoids, phenylethanoids, and flavonoids. When comparing different L. vulgare samples, it was found that the extracts obtained from leaves contained the greatest number of antioxidants. The results of this study suggest that HPTLC-DPPH/ABTS as well as HPLC-ABTS derivatization coupled with the HRMS can be successfully used for profiling and identification of antioxidants from natural sources. Planar chromatography is more suitable for screening multiple samples because of its simplicity, whereas more challenging liquid chromatography provides more detailed information and is therefore better for a selected set of samples.
Assuntos
Antioxidantes , Ligustrum , Antioxidantes/química , Extratos Vegetais/química , Espectrometria de Massas , Cromatografia , Cromatografia Líquida de Alta Pressão/métodosRESUMO
Despite the fact that there are many studies related to the adaptogenic and pro-healthy activities of plant-based compounds, there are some adaptogenic plants whose activities are not fully known, especially those coming from the wild regions of Asia, Africa, and South America. The aim of these studies was to examine the contents of non-nutritional compounds, such as polyphenols, flavonoids, and phenolic acids in ten adaptogenic species (Astragalus membranaceus (AM), Uncaria rhynchophylla (UR), Polygonum multiflorum (PM), Angelica sinensis (AS), Andrographis paniculatea (AP), Tinospora cordifolia (TC), Uncaria tomentosa (UT), Pfaffia paniculate (PP), Sutherlandia frutescens (SF), and Rhaponticum carthamoides (RC)). Considering biological activity, their antioxidant (DPPH, ABTS, FRAP, and ferrous-ion-chelating ability assays), anti-acetylcholinesterase, anti-hyaluronidase, and anti-tyrosinase activities were evaluated. The richest in polyphenols, flavonoids, and phenolic acids was UR (327.78 mg GAE/g, 230.13 mg QE/g, and 81.03 mg CA/g, respectively). The highest inhibitions of acetylcholinesterase, hyaluronidase, and tyrosinase were observed for TC, UR, and PM, respectively. In the case of antioxidant properties, extract from PM appeared to most strongly reduce DPPH, extract from UR inhibited ABTS, and extract from SF showed the best chelating properties. It should be noted that a particularly interesting plant was Ulcaria rhynchophylla. The results mean that there were compounds in UR with broad biological activities, and this species should be explored in more detail. Additionally, our results justify the traditional use of these species in the nutripharmacological or ethnopharmacological care systems of different regions.
Assuntos
Antioxidantes , Fenóis , Antioxidantes/farmacologia , Polifenóis/farmacologia , África , Ásia , América do Sul , Flavonoides , AcetilcolinesteraseRESUMO
The insertion of circular economy principles into the essential oil (EO) production chain aims to reduce waste generation and make integral use of harvested plant material. Higher profits from integral use with reduced waste generation contribute to the eventual use of the EO value chain as an alternative to illicit crops in Colombia (mostly coca). In this study, Java-type citronella (Cymbopogon winterianus) and palmarosa (C. martinii) plant materials were used in two consecutive processes to obtain EOs and extracts. The residual biomass after EO distillation was subjected to ultrasound-assisted hydroethanolic extraction to afford extracts that contained bioactive compounds. Citronella and palmarosa were distilled with typical EO yields (1.0 ± 0.1% for citronella; 0.41 ± 0.06% for palmarosa; n = 5) either through hydrodistillation assisted by microwave radiation or through steam distillation, and their composition (determined via GC/FID/MS analysis) and physicochemical parameters fell within their ISO standard specifications. The concentration of citronellal, the major compound of citronella oil, was 500 ± 152 mg/g. Geraniol, the main component of palmarosa oil, was found at 900 ± 55 mg/g. The citronella and palmarosa hydroalcoholic extracts (4-11% yield) were analyzed with UHPLC-ESI-Orbitrap-MS, which permitted the identification of 30 compounds, mainly C-glycosylated flavones and hydroxycinnamic acids. Both extracts had similar antioxidant activity values, evaluated using the ABTS+â and ORAC assays (110 ± 44 µmol Trolox®/g extract and 1300 ± 141 µmol Trolox®/g extract, respectively).