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1.
Ind Crops Prod ; 191: 115944, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36405420

RESUMEN

Due to the pandemics of COVID-19, herbal medicine has recently been explored for possible antiviral treatment and prevention via novel platform of microbial fuel cells. It was revealed that Coffea arabica leaves was very appropriate for anti-COVID-19 drug development. Antioxidant and anti-inflammatory tests exhibited the most promising activities for C. arabica ethanol extracts and drying approaches were implemented on the leaf samples prior to ethanol extraction. Ethanol extracts of C. arabica leaves were applied to bioenergy evaluation via DC-MFCs, clearly revealing that air-dried leaves (CA-A-EtOH) exhibited the highest bioenergy-stimulating capabilities (ca. 2.72 fold of power amplification to the blank). Furthermore, molecular docking analysis was implemented to decipher the potential of C. arabica leaves metabolites. Chlorogenic acid (-6.5 kcal/mol) owned the highest binding affinity with RdRp of SARS-CoV-2, showing a much lower average RMSF value than an apoprotein. This study suggested C. arabica leaves as an encouraging medicinal herb against SARS-CoV-2.

2.
Molecules ; 27(13)2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35807440

RESUMEN

Culinary herbs and spices are known to be good sources of natural antioxidants. Although the antioxidant effects of individual culinary herbs and spices are widely reported, little is known about their effects when used in combination. The current study was therefore undertaken to compare the antioxidant effects of crude extracts and essential oils of some common culinary herbs and spices in various combinations. The antioxidant interactions of 1:1 combinations of the most active individual extracts and essential oils were investigated as well as the optimization of various ratios using the design of experiments (DoE) approach. The 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays were used to determine the antioxidant activity, and MODDE 9.1® software (Umetrics AB, Umea, Sweden) was used to determine the DoE. The results revealed synergism for the following combinations: Mentha piperita with Thymus vulgaris methanol extract (ΣFIC = 0.32 and ΣFIC = 0.15 using the DPPH and FRAP assays, respectively); Rosmarinus officinalis with Syzygium aromaticum methanol extract (ΣFIC = 0.47 using the FRAP assay); T. vulgaris with Zingiber officinalis methanol extracts (ΣFIC = 0.19 using the ABTS assay); and R. officinalis with Z. officinalis dichloromethane extract (ΣFIC = 0.22 using the ABTS assay). The DoE produced a statistically significant (R2 = 0.905 and Q2 = 0.710) model that was able to predict extract combinations with high antioxidant activities, as validated experimentally. The antioxidant activities of the crude extracts from a selection of culinary herbs and spices were improved when in combination, hence creating an innovative opportunity for the future development of supplements for optimum health.


Asunto(s)
Antioxidantes , Aceites Volátiles , Antioxidantes/farmacología , Metanol , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Proyectos de Investigación
3.
Saudi Pharm J ; 30(6): 793-814, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35812152

RESUMEN

Multitude of diseases and side effects from conventional drugs have surged the use of herbal remedies. Thus, the current study aimed to appraise various pharmacological attributes of Artemisia brevifolia Wall. ex DC. Extracts prepared by successive solvent extraction were subjected to phytochemical and multimode antioxidant assays. Various polyphenolics and artemisinin derivatives were detected and quantified using RP-HPLC analysis. Compounds present in methanol (M) and distilled water (DW) extracts were identified using high resolution mass spectrometry (HRMS). Extracts were pharmacologically evaluated for their antibacterial, antifungal, antimalarial, antileishmanial and antidiabetic potentials. Moreover, cytotoxicity against Artemiasalina, human cancer cell lines and isolated lymphocytes was assessed. Genotoxicity was evaluated using comet, micronucleus and chromosomal aberration assays. Lastly, anti-inflammatory potential was determined through a series of in vitro and in vivo assays using BALB/c mice. Maximum extract recovery (5.95% w/w) was obtained by DW extract. Highest phenolics and flavonoids content, total antioxidant capacity, total reduction potential, percentfree radical scavenging, ß-carotene scavenging and iron chelating activities were exhibited by M extract. RP-HPLC analysis revealed significant amounts of various polyphenolic compounds (vanillic acid, syringic acid, emodin and luteolin), artemisinin, dihydro artemisinin, artesunate and artemether in ethyl acetate (EA) extract. Total 40 compounds were detected through HRMS. A noteworthy antimicrobial activity (MIC 22.22 µg/ml) was exhibited by EA extract against A. fumigatus and several bacterial strains. Maximum antimalarial, antileishmanial, brine shrimp lethality and cytotoxic potential against cancer cells was manifested by EA extract. None of the extracts exhibited genotoxicity and toxicity against isolated lymphocytes. Highest α-amylase and α-glucosidase inhibition capacities were demonstrated by DW extract. Various in-vivo anti-inflammatory models revealed significant (p < 0.05) anti-inflammatory potential of M and DW extracts. In conclusion, present findings divulged theremarkable pharmacological potential of A. brevifolia and endorse its richness in artemisinin.

4.
Saudi Pharm J ; 29(8): 820-832, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34408544

RESUMEN

Anti-tumour efficacy of doxorubicin is hindered by the cumulative dose-dependent cardiotoxicity induced by reactive oxygen species during its metabolism. As Cinnamomum zeylanicum has proven antioxidant potential, objective of this study was to investigate the cardioprotective activity of Cinnamomum bark extract against doxorubicin induced cardiotoxicity in Wistar rats. Physicochemical and phytochemical analysis was carried out and dose response effect and the cardioprotective activity of Cinnamomum were determined in vivo. 180 mg/kg dexrazoxane was used as the positive control. Plant extracts were free of heavy metals and toxic phytoconstituents. In vivo study carried out in Wistar rats revealed a significant increase (p < 0.05) in cardiac troponin I, NT-pro brain natriuretic peptide, AST and LDH concentrations in the doxorubicin control group (18 mg/kg) compared to the normal control. Rats pre-treated with the optimum dosage of Cinnmamomum (2.0 g/kg) showed a significant reduction (p < 0.05) in all above parameters compared to the doxorubicin control. A significant reduction was observed in the total antioxidant capacity, reduced glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase and catalase activity while the lipid peroxidation and myeloperoxidase activity were significantly increased in the doxorubicin control group compared to the normal control (p < 0.05). Pre-treatment with Cinnamomum bark showed a significant decrease in lipid peroxidation, myeloperoxidase activity and significant increase in rest of the parameters compared to the doxorubicin control (p < 0.05). Histopathological analysis revealed a preserved appearance of the myocardium and lesser degree of cellular changes of necrosis in rats pre-treated with Cinnamomum extract. In conclusion, Cinnamomum bark extract has the potential to significantly reduce doxorubicin induced oxidative stress and inflammation in Wistar rats.

5.
Asian-Australas J Anim Sci ; 33(9): 1477-1486, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31480156

RESUMEN

OBJECTIVE: The objective of this study was to evaluate the effect of different levels of lycopene supplementation on the carcass traits, meat quality, concentration of lipid oxidation products and antioxidant potential in the meat and liver of finishing barrows and gilts. METHODS: A total of 40 barrows and 40 gilts were allotted in a completely randomized block design, arranged in a 2×5 factorial scheme, consisting of two sexes (barrows and gilts) and five dietary levels of lycopene (0, 12.5, 25.0, 37.5, and 50.0 mg/kg). In addition, four storage times (0, 24, 48, and 72 h), at 4°C, were added to the model to evaluate the longissimus lumborum muscle. RESULTS: An interaction (p = 0.010) was observed between storage periods and dietary lycopene levels. The unfolding of the interaction (lycopene×period) showed a decreasing concentration of malondialdehyde concentration as the dietary lycopene increased, at all storage periods. No interactions (p>0.050) were observed for the 2,2 diphenyl 1 picrylhydrazyl (DPPH) in the pork. However, the percentage of DPPH radical inhibition reduced (p = 0.001) up to 72 h. Additionally, there was a linear increase (p = 0.001) in the capture of DPPH radicals by antioxidants, as the dietary lycopene increased. No interactions were observed (p>0.05) between the evaluated factors in liver. However, lipid oxidation was reduced by supplementing lycopene in pig diets. The capture of the DPPH radical, resulted increase in the antioxidant power exerted by lycopene in the liver (p = 0.001). The concentrations of the thiobarbituric acid reactive substances and DPPH in the liver were affected by sex (p = 0.001). CONCLUSION: Dietary supplementation of lycopene reduced the water loss during thawing and was effective in protecting against oxidation of the longissimus lumborum muscle and liver until 72 hours of storage, and the best results were obtained by supplementing with 50.0 mg of lycopene/kg of diet.

6.
Bioorg Chem ; 88: 102947, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31028989

RESUMEN

The aerial part of Geophila repens (L.) I.M. Johnst (Rubiaceae) has been used in India to improve intelligence and memory for a long time. As part of our ongoing efforts in discovering potential bioactive compounds from G. repens, we have studied the isolation, identification, and quantification of a new class of cholinesterase inhibitor from G. repens for Alzheimer's disease (AD). Terpene was isolated from hydroalcohol extract of G. repens (GRHA) and its structure was identified "Pentylcurcumene" by spectroscopic data. HPTLC fingerprint analysis was performed and good separation was achieved in mobile phase (benzene:methanol; 7.5:2.5, v/v, 254 and 366 nm; Rf 0.51). The method was validated using ICH guidelines in terms of linearity, specificity, sensitivity, accuracy, precision, robustness and stability. In cellular antioxidant studies e.g. DPPH, oxygen-radical-absorbance-capacity (ORAC) and cell-based-antioxidant-protection-in-erythrocytes (CAP-e) assays showed that, Pentylcurcumene showed remarkably different degrees of antioxidant activities in dose-dependent manner. Pentylcurcumene demonstrated anticholinesterase activities e.g. IC50 of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition were 73.12 ±â€¯0.56 and 97.65 ±â€¯0.46 µg/ml, respectively. To better understand enzyme kinetics, Lineweaver-Burk plot of Pentylcurcumene displayed the highest affinity with competitive inhibition (reversible) towards both AChE (Vmax 0.8) and BChE (Vmax 0.6). An improved and advanced HPTLC tool of bioautography detection of Pentylcurcumene has been successfully demonstrated its anticholinesterase activities. Molecular docking simulations of Pentylcurcumene (ligand) and enzymes (proteins) exhibited the binding of ligand at active sites of AChE (human/rat) and BChE (human/homology) efficiently and also predicted the hydrophobic interaction of drug towards different amino acid residue within proteins. As per the results of antioxidant study and with the support of molecular docking analysis, it is concluded that Pentylcurcumene could be a potential first-line cholinesterase-inhibitor for AD.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Antioxidantes/farmacología , Inhibidores de la Colinesterasa/farmacología , Curcumina/farmacología , Extractos Vegetales/farmacología , Rubiaceae/química , Acetilcolinesterasa/metabolismo , Enfermedad de Alzheimer/metabolismo , Animales , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo/antagonistas & inhibidores , Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/aislamiento & purificación , Curcumina/análogos & derivados , Curcumina/aislamiento & purificación , Humanos , Modelos Moleculares , Estructura Molecular , Picratos/antagonistas & inhibidores , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Ratas , Ratas Wistar
7.
Mol Divers ; 23(4): 885-896, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30656505

RESUMEN

In the present study, iron oxide magnetic nanoparticles (Fe3O4 MNPs) were synthesized in a green biosynthetic manner using aqueous extract of clover leaves. Fe3O4 MNPs were applied as a magnetically separable nanocatalyst for the green syntheses of functionalized [1,3]-oxazoles 1(a-e) and 1H-pyrrolo-[1,3]-oxazoles 4(a-i) as promising antioxidant compounds in excellent yields at 50 °C and room temperature, respectively. The antioxidant activities of the most stable compounds (1a, 1b, 4a, and 4b) were evaluated by both 2,2-diphenyl-1-picrylhydrazyl radical scavenging and ferric reduction activity potential assays. Compound 1b was shown a remarkable radical scavenging activity, and 4a was shown very good reducing activity relative to standards (BHT and TBHQ).


Asunto(s)
Antioxidantes/síntesis química , Nanopartículas de Magnetita/química , Medicago , Oxazoles/síntesis química , Extractos Vegetales/química , Antioxidantes/química , Compuestos de Bifenilo/química , Catálisis , Tecnología Química Verde , Oxazoles/química , Picratos/química , Hojas de la Planta
8.
Molecules ; 24(16)2019 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-31412565

RESUMEN

Twenty commercially available oenological tannins (including hydrolysable and condensed) were assessed for their antiradical/reducing activity, comparing two analytical approaches: The 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging spectrophotometric assay and the cyclic voltammetry (CV) electrochemical method. Electrochemical measurements were performed over a -200 mV-500 mV scan range, and integrated anodic currents to 500 mV were used to build a calibration graph with (+)-catechin as a reference standard (linear range: From 0.0078 to 1 mM, R2 = 0.9887). The CV results were compared with the DPPH• assay (expressed as % of radical scavenged in time), showing high correlation due to the similarity of the chemical mechanisms underlying both methods involving polyphenolic compounds as reductants. Improved correlation was observed by increasing the incubation time with DPPH• to 24 h (R2 = 0.925), demonstrating that the spectrophotometric method requires a long-term incubation to complete the scavenging reaction when high-molecular weight tannins are involved; this constraint has been overcome by using instant CV measurements. We concluded that the CV represents a valid alternative to the DPPH• colorimetric assay, taking advantage of fast analysis and control on the experimental conditions and, because of these properties, it can assist the quality control along the supply chain.


Asunto(s)
Antioxidantes/química , Compuestos de Bifenilo/química , Picratos/química , Taninos/química , Antioxidantes/farmacología , Compuestos de Bifenilo/farmacología , Picratos/farmacología , Espectrofotometría
9.
Molecules ; 24(6)2019 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-30871172

RESUMEN

Digestive enzymes and free radical inhibitors are used to prevent complications resulting from diabetes. Entada spiralis (family Leguminosae), which is a well-known medicinal plant in herbal medicine due to its various traditional and medicinal applications, was studied. Crude extracts were successively obtained from the stem bark using petroleum ether, chloroform and methanol as extracting solvents. The antioxidant activity of all the extracts, fractions and isolated compounds were estimated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ß-carotene and 2,2'-azinobis(-3-ethylbenzothiazine-6-sulfonic acid) (ABTS) assays, while digestive enzymes inhibitory activity was assessed using α-amylase and α-glucosidase inhibitory methods. Structure elucidation of pure compounds was achieved through different spectroscopic analysis methods. Fractionation and purification of the most active methanol extract resulted in the isolation of a ferulic ester namely; (e)-hexyl 3-(4-hydroxy-3-methoxyphenyl) acrylate (FEQ-2) together with five known phenolic constituents, identified as kaempferol (FEQ-3), 5,4'-dihydroxy-3,7,3'-trimethoxyflavone (FEQ-2), gallic acid (FEQ-5), (+)-catechin (FEQ-7) and (-)-epicatechin (FEQ-8). FEQ-5 exhibited the strongest antioxidant and enzyme inhibitory activities followed by FEQ-3 and FEQ-4. FEQ-2 also displayed potent free radical scavenging activity with IC50 values of 13.79 ± 2.13 (DPPH) and 4.69 ± 1.25 (ABTS) µg/mL, respectively. All other compounds were found active either against free radicals or digestive enzymes.


Asunto(s)
Antioxidantes/química , Inhibidores Enzimáticos/química , Fabaceae/química , Fitoquímicos/química , Antioxidantes/farmacología , Fraccionamiento Químico , Inhibidores Enzimáticos/farmacología , Flavonoides/aislamiento & purificación , Inhibidores de Glicósido Hidrolasas , Estructura Molecular , Fitoquímicos/farmacología , Corteza de la Planta/química , Tallos de la Planta/química , Plantas Medicinales/química , alfa-Amilasas/antagonistas & inhibidores
10.
J Enzyme Inhib Med Chem ; 32(1): 640-647, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28262029

RESUMEN

2,2-Diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging, the most commonly used antioxidant method with more than seventeen thousand articles cited, is very practical; however, as with most assays, it has the major disadvantage of dependence on a spectrophotometer. To overcome this drawback, the colorimetric determination of the antioxidant activity using a scanner and freely available Image J software was developed. In this new method, the mixtures of solutions of DPPH• and standard antioxidants or extracts of common medicinal herbs were dropped onto TLC plates, after an incubation period. The spot images were evaluated with Image J software to determine CSC50 values, the sample concentrations providing 50% colour reduction, which were very similar with the SC50 values obtained with spectrophotometric method. The advantages of the new method are the use of lower amounts of reagents and solvents, no need for costly spectrophotometers, and thus significantly lowered costs, and convenient implementation in any environment and situation.


Asunto(s)
Antioxidantes/química , Compuestos de Bifenilo/química , Colorimetría/métodos , Picratos/química , Plantas Medicinales/química , Antioxidantes/síntesis química , Antioxidantes/farmacología , Colorimetría/tendencias , Ácido Gálico/química , Reproducibilidad de los Resultados , Espectrofotometría
11.
Acta Biochim Biophys Sin (Shanghai) ; 49(10): 945-953, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-28981602

RESUMEN

Orostachys japonicus is an herb that contains several functional components and has traditionally been used to treat various diseases in Asia. In this study, bioactive components from different parts of the O. japonicus plant were investigated, and the contents of the functional components in ethanol extracts of O. japonicus cultivated in Korea and China were compared. The antioxidant effects of O. japonicus ethanol extracts were investigated using Raw 264.7 cells. It was found that 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity was significantly decreased in the cells treated with the extracts. Moreover, the novel inhibitory functions of O. japonicus extracts on collagenase, elastase, and tyrosinase were established. We also found that O. japonicus extracts strongly inhibited melanin synthesis in B16F10 melanoma cells by decreasing MITF protein levels and activating the Erk and Akt signaling pathways. Thus, these findings would be useful for developing new cosmetic and pharmaceutical formulations based on O. japonicus extracts.


Asunto(s)
Colagenasas/metabolismo , Crassulaceae/química , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Extractos Vegetales/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Línea Celular Tumoral , China , Etanol/química , Melaninas/antagonistas & inhibidores , Melaninas/biosíntesis , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Monofenol Monooxigenasa/antagonistas & inhibidores , Monofenol Monooxigenasa/metabolismo , Elastasa Pancreática/antagonistas & inhibidores , Elastasa Pancreática/metabolismo , Extractos Vegetales/química , Células RAW 264.7 , República de Corea , Transducción de Señal/efectos de los fármacos
12.
Pharm Biol ; 55(1): 1337-1347, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28298169

RESUMEN

CONTEXT: Marrubium vulgare Linn (Lamiaceae) was generally extracted by conventional methods with low yield of marrubiin; these processes were not considered environment friendly. OBJECTIVE: This study extracts the whole plant of M. vulgare by microwave assisted extraction (MAE) and optimizes the effect of various extraction parameters on the marrubiin yield by using Central Composite Design (CCD). MATERIALS AND METHODS: The selected medicinal plant was extracted using ethanol: water (1:1) as solvent by MAE. The plant material was also extracted using a Soxhlet and the various extracts were analyzed by HPTLC to quantify the marrubiin concentration. RESULTS: The optimized conditions for the microwave-assisted extraction of selected medicinal plant was microwave power of 539 W, irradiation time of 373 s and solvent to drug ratio, 32 mL per g of the drug. The marrubiin concentration in MAE almost doubled relative to the traditional method (0.69 ± 0.08 to 1.35 ± 0.04%). The IC50 for DPPH was reduced to 66.28 ± 0.6 µg/mL as compared to conventional extract (84.14 ± 0.7 µg/mL). The scanning electron micrographs of the treated and untreated drug samples further support the results. DISCUSSION AND CONCLUSION: The CCD can be successfully applied to optimize the extraction parameters (MAE) for M. vulgare. Moreover, in terms of environmental impact, the MAE technique could be assumed as a 'Green approach' because the MAE approach for extraction of plant released only 92.3 g of CO2 as compared to 3207.6 g CO2 using the Soxhlet method of extraction.


Asunto(s)
Antioxidantes/aislamiento & purificación , Dióxido de Carbono , Diterpenos/aislamiento & purificación , Marrubium , Microondas , Extractos Vegetales/aislamiento & purificación , Antioxidantes/química , Diterpenos/química , Evaluación Preclínica de Medicamentos/métodos , Componentes Aéreos de las Plantas , Extractos Vegetales/química
13.
J Dairy Sci ; 99(2): 903-914, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26709186

RESUMEN

Twelve isolates isolated from the gastrointestinal tracts of Gaotian villagers in China, who had a lifespan of 92 yr, were examined for their antioxidants using free radical scavenging activity and 2,2-diphenyl-1-picrylhydrazyl. Three strains (i.e., Lactobacillus mucosae LMU1001, and Lactobacillus plantarum LPL0902 and LPL0302) were selected as candidates to prepare yogurt for testing their antioxidants in a model of d-galactose-induced aging mice, with vitamin C as a positive control. The results showed that L. mucosae LMU1001 was the best strain, which had similar in vivo antioxidant activity as vitamin C. A significant increase was found in the activities of glutathione peroxidase in serum and total superoxide dismutase in the liver, and a decrease in the level of malondialdehyde in serum. Regarding mRNA expression level detected quantitatively by real-time PCR, we observed that L. mucosae LMU1001 significantly upregulated antioxidant genes (i.e., MT1A and MT1M in HT-29 and Caco-2) and those genes (i.e., MT1, MT2, GPx1, and GPx2) in the intestinal tract of the model mice. Hence, this strain could be considered as a potential probiotic lactic acid bacterium for improving antioxidant levels in functional foods.


Asunto(s)
Envejecimiento , Antioxidantes/análisis , Galactosa/farmacología , Intestinos/microbiología , Lactobacillus/fisiología , Anciano de 80 o más Años , Envejecimiento/efectos de los fármacos , Animales , Antioxidantes/metabolismo , Células CACO-2 , China , Alimentos Funcionales , Glutatión Peroxidasa/sangre , Humanos , Lactobacillus/aislamiento & purificación , Lactobacillus plantarum/fisiología , Hígado/enzimología , Longevidad , Malondialdehído/sangre , Ratones , Modelos Animales , Probióticos , Superóxido Dismutasa/metabolismo
14.
Int J Mol Sci ; 17(8)2016 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-27483242

RESUMEN

Radical-scavenging antioxidants play crucial roles in the protection of unsaturated oils against autoxidation and, especially, edible oils rich in omega-3 because of their high sensitivity to oxygen. Two complementary tools are employed to select, among a large set of natural and synthetic phenols, the most promising antioxidants. On the one hand, density functional theory (DFT) calculations provide bond dissociation enthalpies (BDEs) of 70 natural (i.e., tocopherols, hydroxybenzoic and cinnamic acids, flavonoids, stilbenes, lignans, and coumarins) and synthetic (i.e., 2,6-di-tert-butyl-4-methylphenol (BHT), 3-tert-butyl-4-hydroxyanisol (BHA), and tert-butylhydroquinone (TBHQ)) phenols. These BDEs are discussed on the basis of structure-activity relationships with regard to their potential antioxidant activities. On the other hand, the kinetic rate constants and number of hydrogen atoms released per phenol molecule are measured by monitoring the reaction of phenols with 2,2-diphenyl-1-picrylhydrazyl (DPPH(•)) radical. The comparison of the results obtained with these two complementary methods allows highlighting the most promising antioxidants. Finally, the antioxidant effectiveness of the best candidates is assessed by following the absorption of oxygen by methyl esters of linseed oil containing 0.5 mmol L(-1) of antioxidant and warmed at 90 °C under oxygen atmosphere. Under these conditions, some natural phenols namely epigallocatechin gallate, myricetin, rosmarinic and carnosic acids were found to be more effective antioxidants than α-tocopherol.


Asunto(s)
Antioxidantes/análisis , Antioxidantes/química , Ácidos Grasos Omega-3/química , Modelos Teóricos , Fenoles/química , Aceites de Plantas/química , Cinética , Oxidación-Reducción , Fenoles/clasificación
15.
Zhongguo Zhong Yao Za Zhi ; 41(14): 2660-2668, 2016 Jul.
Artículo en Zh | MEDLINE | ID: mdl-28905603

RESUMEN

This paper aims to investigate the correlation between the antioxidant activity of Prunella vulgaris and its total phenolic acids content by measuring the antioxidant activity of different sources and different organs of P. vulgaris and the total contents of protocatechuic acid, protocatechuic aldehyde, caffeic acid, salviaflaside and rosmarinic acid in these samples. Using the 50% methanol extract of P. vulgaris samples as the research object, DPPH method and HPLC method were used respectively to determine the antioxidant activities and the total contents of the above-mentioned five analytes in P. vulgaris samples. 0.5 mL of 50% methanol extract of P. vulgaris reacts with 0.1 mmol•L⁻¹ DPPH ethanol solution for 60 min, then the absorbance of the reaction solution was measured at 517 nm, scavenging rate and IC50 values were calculated by the absorbance and the sample concentration for evaluating the antioxidant activity. HPLC analysis was made on a C18 Epic column, with acetonitrile-0.1% formic acid aqueous solution as mobile phase (gradient elution), and the detection wavelength was set at 280 nm. The correlation between the antioxidant capacity of different habitats and different organs of P. vulgaris and the total contents of five kinds of phenolic acids was analyzed by partial least squares method. The reaction dose-response range of 50% methanol extract of P. vulgaris with 0.1 mmol•L⁻¹ DPPH ethanol solution was 0.300-1.65 g•L⁻¹. When the quantities of potocatechuic acid, protocatechuic aldehyde, caffeic acid, salviaflaside and rosmarinic acid were respectively in 0.007 84-0.980, 0.011 5-1.44, 0.008 64-1.08, 0.080 0-1.00 and 0.079 8-0.998 µg range, their quantities were in good linear relationship with the corresponding peak areas. The average recovery of 5 components were 97.76%, 96.88%, 100.3%, 102.1%, 104.5%, with RSD of 1.8%, 1.6%, 1.7%, 1.6% and 1.7%, respectively. In a certain range of crude drug quantity, the antioxidant activity of each organ of P. vulgaris and total phenolic acids content inside has a good linear correlation. Therefore, in certain quality range of crude drug, DPPH bioassay combined with HPLC content determination can be used for the quality control of P. vulgaris, as is a new method for the quality control of P. vulgaris.


Asunto(s)
Antioxidantes/análisis , Medicamentos Herbarios Chinos/normas , Hidroxibenzoatos/análisis , Prunella/química , Bioensayo , Cromatografía Líquida de Alta Presión , Extractos Vegetales
16.
J Gen Appl Microbiol ; 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39085095

RESUMEN

We have successfully isolated two novel compounds, 24R005A (1, C13H14O4) and 24R005B (2, C13H13ClO4), from Streptomyces sp. 24R005, using fish (anchovy) powder as a medium. In this study, we evaluated the use of fish (anchovy) powder as a fermentation material for producing bioactive compounds. Spectroscopic analyses revealed that the two compounds share a common skeletal structure. However, each compound contains unique branched side chains. Furthermore, compounds 1 and 2 exhibit moderate radical-scavenging activity for 1,1-diphenyl-2-picrylhydrazyl (DPPH), with ED50 values of 200 and 130 µM, respectively.

17.
Pak J Biol Sci ; 27(2): 69-79, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38516748

RESUMEN

<b>Background and Objective:</b> Pepino (<i>Solanum muricatum</i> Aiton), rich with vitamin C and flavonoids, constitutes an abundant source of potent antioxidants. This research was conducted to determine antioxidant activity from three different parts of pepino based on equivalence with ascorbic acid, to analyze the relationship between total phenolic content (TPC) and total flavonoid content (TFC) on antioxidant activities and to determine flavonoid compounds. <b>Materials and Methods:</b> Antioxidant activities were determined using 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) and Cupric Ion Reducing Antioxidant Capacity (CUPRAC) methods. The TPC and TFC were determined by UV-visible spectrophotometry. The correlation between TPC, TFC and antioxidant activity was analyzed using Pearson's method. Flavonoid compound content was performed by HPLC. <b>Results:</b> The ethyl acetate pepino fruit extract expressed the highest antioxidant activity by DPPH and CUPRAC assays. The highest TPC was obtained from the ethyl acetate extract of pepino stem (18.493 g GAE/(100 g)), while the highest TFC was obtained from the hexane extract of pepino leaves (9.541 g QE/(100 g)). <b>Conclusion:</b> The DPPH and CUPRAC assays demonstrated that pepino exhibits potential as a source of natural antioxidants, especially in its fruit part.


Asunto(s)
Acetatos , Antioxidantes , Solanum , Antioxidantes/química , Frutas/química , Solanum/química , Extractos Vegetales/química , Flavonoides/análisis , Ácido Ascórbico , Fenoles/química
18.
Bot Stud ; 65(1): 4, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38252177

RESUMEN

BACKGROUND: Recently, researchers are focusing on creating new tools to combat the antibiotic resistant bacteria and malignancy issues, which pose significant threats to humanity. Biosynthesized silver nanoparticles (AgNPs) are thought to be a potential solution to these issues. The biosynthesis method, known for its environmentally friendly and cost-effective characteristics, can produce small-sized AgNPs with antimicrobial and anticancer properties. In this study, AgNPs were bio-fabricated from the distilled water and methanolic extracts of Viburnum grandiflorum leaves. Physio-chemical characterization of the bio-fabricated AgNPs was conducted using UV-visible spectroscopy, scanning electron microscopy, energy dispersive X-ray, and X-ray diffraction analysis. RESULTS: AgNPs produced from the methanol extract were smaller in size (12.28 nm) compared to those from the aqueous extract (17.77 nm). The bioengineered AgNPs exhibited a circular shape with a crystalline nature. These biosynthesized AgNPs demonstrated excellent bactericidal activity against both gram-negative (Pseudomonas aeruginosa) and gram-positive (Staphylococcus aureus) bacteria. Highest antibacterial activity was observed with the methanol extract against P. aeruginosa (14.66 ± 0.74 mm). AgNPs from the methanol extract also displayed the highest antioxidant activity, with an IC50 value of 188.00 ± 2.67 µg/mL against 2,2-diphenyl-1-picrylhydrazyl (DPPH). Furthermore, AgNPs exhibited notable cytotoxic activity against Rhabdomyosarcoma cell line (RD cell) of human muscle cancer cell. The IC50 values calculated from the MTT assay were 26.28 ± 1.58 and 21.49 ± 1.44 µg/mL for AgNPs synthesized from aqueous and methanol extracts, respectively. CONCLUSION: The methanol extract of V. grandiflorum leaves demonstrates significant potential for synthesizing AgNPs with effective antibacterial, antioxidant, and anticancer actions, making them applicable in various biomedical applications.

19.
Nat Prod Res ; : 1-8, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38623836

RESUMEN

The aim of the study was to investigate the relationship between flavonoids in Abrus precatorius leaves (APL) and their hypoglycaemic effects, which have not been studied before. An efficient purification process, transcriptomics and network pharmacology analysis were applied for the first time. High-performance liquid chromatography (HPLC) was used to determine the content of total flavonoids. The results showed that D101 resin was most suitable for purification of flavonoids of APL, which could increase its purity from 25.2% to 85.2% and achieve a recovery rate of 86.9%. The analysis of transcriptomics and network pharmacology revealed that flavonoids of APL could play a hypoglycaemic role by regulating 31 targets through AGE-RAGE and other signal pathways. Flavonoids of APL could exert hydroglycaemic effects by inhibiting AGEs, α-glucosidase and DPPH. This study provides a solid basis for hypoglycaemic product development and in-depth research of flavonoids in APL.

20.
Mutat Res Genet Toxicol Environ Mutagen ; 757(2): 167-72, 2013 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-23973768

RESUMEN

We investigated whether combinations of ascorbic acid (AA) plus dietary polyphenols can protect in vivo against genotoxic damage induced by endogenous nitrosation. A nitrosation reaction mixture consisting of methylurea (MU) plus sodium nitrite (SN), which can react to form N-nitroso-N-methylurea in the stomach, was administered orally to mice, together with AA and one of the dietary polyphenols ferulic acid (FA), gallic acid (GA), chlorogenic acid (CA), or epigallocatechin gallate (EGCG). Genotoxic damage in bone marrow cells was assessed by measuring micronucleated polychromatic erythrocytes (Mn PCEs) and metaphase chromosome aberrations. When compared to damage induced by MU plus SN alone, co-administration with AA, FA, GA, CA, or EGCG resulted in significant protective effects. Combinations of AA plus EGCG or AA plus CA showed a further protective effect. Reduction in the frequency of Mn PCEs to the control level was obtained following co-administration of a combination of AA, FA, GA, and CA with MU plus SN. A similar trend was observed for metaphase chromosome aberrations. Co-administration of AA, FA, GA, or CA with N-nitroso-N-methylurea (MNU) did not show any significant reduction in genotoxicity, indicating the absence of a protective effect against a preformed N-nitroso compound. Our work demonstrates the protective effects of the 'antinitrosating' combination of AA and dietary polyphenols FA, GA, or CA against genotoxic damage induced by an endogenously formed N-nitroso compound.


Asunto(s)
Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Aberraciones Cromosómicas/efectos de los fármacos , Daño del ADN , Suplementos Dietéticos , Polifenoles/farmacología , Animales , Células de la Médula Ósea/metabolismo , Células de la Médula Ósea/patología , Eritroblastos/metabolismo , Eritroblastos/patología , Masculino , Ratones , Micronúcleos con Defecto Cromosómico , Nitrosación/efectos de los fármacos , Compuestos Nitrosos/metabolismo
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