19 results on '"Sousa RMF"'
Search Results
2. Phytochemical Profiling by HPLC-ESI-MS/MS and In Vitro Investigation of the Antidiabetic Activity of Cassia bakeriana Bark Extract and Fractions.
- Author
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Prado DG, Justino AB, Silva TDC, de Morais SAL, Martins MM, Santos PS, Cunha LCS, de Sousa RMF, de Aquino FJT, Espindola FS, and de Oliveira A
- Subjects
- Chromatography, High Pressure Liquid methods, Animals, Phytochemicals pharmacology, Phytochemicals chemistry, Phytochemicals analysis, Glycoside Hydrolase Inhibitors pharmacology, Glycoside Hydrolase Inhibitors chemistry, alpha-Glucosidases metabolism, alpha-Glucosidases chemistry, Glycation End Products, Advanced, Vero Cells, Chlorocebus aethiops, Cell Survival drug effects, Humans, Plant Extracts pharmacology, Plant Extracts chemistry, Cassia chemistry, Plant Bark chemistry, Hypoglycemic Agents pharmacology, Hypoglycemic Agents chemistry, Tandem Mass Spectrometry methods, Spectrometry, Mass, Electrospray Ionization methods, alpha-Amylases antagonists & inhibitors, Antioxidants pharmacology, Antioxidants chemistry
- Abstract
Type 2 diabetes mellitus is a global health problem, placing patients at a higher risk of developing cardiovascular diseases and cancer. This study investigates the antidiabetic potential of Cassia bakeriana bark extracts and fractions. We evaluate their ability to inhibit α-amylase and α-glucosidase enzymes and advanced glycation end-products (AGEs). The antioxidant potential was also examined. Extracts were prepared through maceration with hexane (HE) and ethanol (EE), and the fractions were obtained via liquid-liquid extraction from EE. Anti-enzymatic, anti-glycation, antioxidant, and cytotoxic assays were conducted in 96-well plates using different concentrations of samples to determine the half-maximal inhibitory concentration (IC
50 ). Active samples were further analyzed using HPLC-(-)-ESI-MS/MS. The ethyl acetate fraction (EAF) demonstrated a high percentage of α-amylase inhibition (94.0%) with a promising IC50 value of 1.05 μg mL-1 . Additionally, EAF displayed 61.5% inhibition of α-glucosidase, with an IC50 value of 537 μg mL-1 . The EE, EAF, and n-butanol fraction (BF) exhibited strong anti-glycation capacities. Furthermore, the EE, EAF, BF, and dichloromethane fractions showed promising antioxidant activity using the DPPH and ORAC methodologies. Cytotoxic activity was also evaluated with Vero cells, revealing no adverse effects on cell viability (CC50 > 512.0 μg mL-1 ). Active samples predominantly comprised proanthocyanidins, flavonoids, and anthraquinone, representing the main constituents of C. bakeriana bark. This study provides the first assessment of the antidiabetic potential of C. bakeriana bark and a comprehensive analysis of the chemical composition of its active extracts and fractions, offering hope for future treatments., (© 2024 John Wiley & Sons Ltd.)- Published
- 2024
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3. Exploring the selective incorporation of 15β-senecioyloxi-ent-kaurenoic acid methyl ester in Langmuir monolayers mimicking cell membranes.
- Author
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da Silva GHO, Dos Santos KF, Barcellos AF, de Sousa RMF, Tempone AG, Lago JHG, and Caseli L
- Abstract
A natural product isolated from Brazilian plant species Baccharis retusa (Asteraceae), 15β-senecioyloxi-ent-kaurenoic acid (1), demonstrated activity against trypomastigotes of the parasite Trypanosoma cruzi but it was inactive against intracellular forms. In the present work, compound 1a, a methyl ester derivative of 1, exhibited activity against intracellular amastigotes (EC
50 = 11.8 μM), similar to that determined by the standard drug benznidazol (EC50 = 16.2 μM) and no toxicity against NCTC cells (CC50 > 200 μM). Based on this selectivity, compound 1a was incorporated into Langmuir monolayers of three lipids, DPPC, DPPE, and DPPS, to characterize the interaction of the compound with each lipid as model for cell membranes. For that, we used tensiometry, surface potential measurements, and infrared spectroscopy. Our results showed that incorporating the drug into DPPC monolayers significantly altered the physicochemical properties, resulting in more condensed monolayers. In contrast, the incorporation of the drug into DPPE and DPPS monolayers led to their expansion. The effects on DPPC were more pronounced than on the other lipids, inducing a viscoelastic monolayer with lower alignment of the alkyl chains, as observed through surface potential measurements and infrared spectroscopy. These changes indicate a more cohesive DPPC monolayer upon drug incorporation, forming domains in a strip shape. We believe these results contribute to understanding the interaction between 1a and lipid interfaces, especially those involved in biological interactions with amastigotes of parasite T. cruzi., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)- Published
- 2024
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4. Green Lacewing Chrysoperla externa Is Attracted to Volatile Organic Compounds and Essential Oils Extracted from Eucalyptus urograndis Leaves.
- Author
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Borges DJV, Souza RAC, de Oliveira A, de Sousa RMF, Venâncio H, Demetrio GR, Ambrogi BG, and Santos JC
- Abstract
Plant herbivore interactions have long been recognized as a complex interplay influenced by various factors, including plant volatile emissions. Understanding the role of these volatiles in mediating plant predator interactions is crucial for developing sustainable pest management strategies. This study investigated the olfactory preferences of Chrysoperla externa larvae for volatiles emitted by Eucalyptus urograndis leaves, focusing on both seedlings and essential oils (EOs). We used Y-tube olfactometry to compare larval preferences between the clean air and various plant treatments, including undamaged and herbivore-damaged leaves. Chemical analysis of EOs revealed higher concentrations of oxygenated monoterpenes and sesquiterpenes in young and damaged leaves, particularly linalool, which has been implicated in insect attraction. Our results showed a significant preference for volatiles emitted by young damaged leaves over clean air for both seedlings (χ
2 = 11.03, p = 0.001) and EOs (χ2 = 9.76, p = 0.002). Chrysoperla externa larvae are significantly attracted to specific volatiles from damaged E. urograndis leaves, suggesting these compounds could serve as cues for natural enemy foraging. Our findings enhance the understanding of plant-predator dynamics and suggest potential applications of eucalyptus plantations to sustain C. externa populations for biocontrol purposes.- Published
- 2024
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5. Cosmetic Preservative Potential and Chemical Composition of Lafoensia replicata Pohl. Leaves.
- Author
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Lima DM, Santos ALO, Melo MRS, Tavares DC, Martins CHG, and Sousa RMF
- Abstract
The study evaluated the preservative potential of Lafoensia replicata Pohl. leaf extracts in cosmetics, highlighting their antioxidant, antimicrobial, and in vitro cytotoxic activities for ethanolic extract prepared by the maceration and tincture method. Total phenol content showed a higher phenol concentration in ethanolic extract and tinctures, and by LC-MS/MS-ESI-QTOF analysis, flavonoids, hydrolyzed tannins, and phenolic acids were identified. The ethanolic extract and tincture showed high antimicrobial activity against Staphylococcus aureus , Pseudomonas aeruginosa , and Candida albicans (MIC < 50 µg mL
-1 ), high antioxidant activity (EC50 < 50 µg mL-1 in the DPPH method, and results > 450 µmol trolox equivalent in the ABTS and FRAP method), and low cytotoxicity in human keratinocytes (IC50 > 350 µg mL-1 ). The results suggest these extracts could be an alternative to synthetic preservatives in the cosmetic industry.- Published
- 2024
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6. Chemical Composition of Extracts and Fractions from Miconia Ibaguensis (Melastomataceae) Leaves and Evaluation of Biological Activities.
- Author
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Sehnem GS, Silva JA, da C Silva T, Prado DG, Santiago MB, O Santos AL, Martins MM, Cunha LCS, Sousa RMF, Romero R, Bittar VP, Borges ALS, Martins CHG, Espindola FS, and de Oliveira A
- Subjects
- Candida drug effects, alpha-Amylases antagonists & inhibitors, alpha-Amylases metabolism, Flavonoids chemistry, Flavonoids pharmacology, Flavonoids isolation & purification, Chromatography, High Pressure Liquid, Plant Leaves chemistry, Plant Extracts chemistry, Plant Extracts pharmacology, Plant Extracts isolation & purification, Melastomataceae chemistry, Antioxidants pharmacology, Antioxidants chemistry, Antioxidants isolation & purification, Microbial Sensitivity Tests, Antifungal Agents pharmacology, Antifungal Agents chemistry, Antifungal Agents isolation & purification, Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents chemistry, Anti-Bacterial Agents isolation & purification, Hypoglycemic Agents pharmacology, Hypoglycemic Agents chemistry, Hypoglycemic Agents isolation & purification
- Abstract
The study aimed to assess the chemical composition of Miconia ibaguensis leaves extracts and fractions obtained from the ethanolic extract (EE), along with evaluating their antifungal, antibacterial, antidiabetic, and antioxidant activities. The ethyl acetate fraction (EAF) exhibited potent antifungal activity against Candida spp (1.95-3.90 μg mL
-1 ) and potent antioxidant activity in the DPPH (1.74±0.07 μg mL-1 ), FRAP (654.01±42.09 μmol ETrolox /gsample ), and ORAC (3698.88±37.28 μmol ETrolox /gsample ) methods. The EE displayed inhibition against the α-amylase enzyme (8.42±0.05 μg mL-1 ). Flavonoids, hydrolysable tannins, triterpenoids, and phenolic acids, identified in the EE and fractions via (-)-HPLC-ESI-MS/MS analysis, were found to contribute to the species' biological activity potentially. These findings suggest promising avenues for further research and potential applications in pharmacology and natural products, offering new possibilities in the fight against global health issues., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)- Published
- 2024
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7. An In Vivo Assessment of the Effect of Hexane Extract from Endlicheria paniculata Branches and Its Main Compound, Methyldehydrodieugenol B, on Murine Sponge-Induced Inflammation.
- Author
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Ferreira BA, Souza RAC, de Moura FBR, Silva TDC, Adriano TDS, Franca EF, de Sousa RMF, Araújo FA, Lago JHG, and de Oliveira A
- Subjects
- Mice, Animals, Tissue Distribution, Plant Extracts pharmacology, Inflammation drug therapy, Anti-Inflammatory Agents pharmacology, Basic Helix-Loop-Helix Transcription Factors, Hexanes, Lauraceae chemistry
- Abstract
The present study aims to explore the anti-inflammatory potential activity of the hexane extract from branches (HEB) of Endlicheria paniculata (Lauraceae) and its main compound, methyldehydrodieugenol B, in the inflammatory response induced by a murine implant sponge model. HPLC-ESI/MS analysis of HEB led to the identification of six chemically related neolignans, with methyldehydrodieugenol B as the main compound. An in silico analysis of the pharmacokinetic parameters of the identified compounds suggested moderate solubility but good absorption and biodistribution in vivo. Thus, the treatment of mice with HEB using in vivo assays indicated that HEB promoted pro-inflammatory, antiangiogenic, and antifibrogenic effects, whereas treatment with methyldehydrodieugenol B caused anti-inflammatory, antifibrogenic, and antiangiogenic effects. The obtained results shown the therapeutic potential of HEB and methyldehydrodieugenol B in the treatment of pathologies associated with inflammation and angiogenesis, including chronic wounds.
- Published
- 2023
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8. Influence of water matrix components and peroxide sources on the transformation products and toxicity of tebuthiuron under UVC-based advanced oxidation processes.
- Author
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Gonçalves BR, Della-Flora A, Sirtori C, Sousa RMF, V M Starling MC, Sánchez Pérez JA, Saggioro EM, Sales Junior SF, and Trovó AG
- Subjects
- Peroxides, Hydrogen Peroxide chemistry, Water, Oxidation-Reduction, Ultraviolet Rays, Water Pollutants, Chemical analysis, Water Purification methods
- Abstract
Coupling of UV-C irradiation to different peroxides (H
2 O2 , S2 O8 2- and HSO5 - ) has great potential to degrade persistent organic compounds due to the formation of HO• or SO4 •- species. However, an in-depth comparison between the performance of different UV-C/peroxide processes as a function of (i) target compound degradation, (ii) generated transformation products and (iii) lethal/sub lethal toxicity effects has not yet been performed. To this end a comparison study was carried out to evaluate the effectiveness of different UV-C/peroxide processes using the herbicide tebuthiuron (100 or 500 μg L-1 ) as a model pollutant. TBH degradation experiments were performed at lab-scale in real municipal wastewater treatment plant effluent and distilled water. Faster degradation occurred by increasing peroxide concentration from 735 to 2206 μmol L-1 in the municipal wastewater treatment plant effluent, mainly for S2 O8 2- . Experiments performed in the presence of peroxide trapping agents - HO• and SO4 •- (methoxibenzene) or HO• (2-propanol) - revealed that oxidation in the UV-C/S2 O8 2- system occurs mainly through SO4 •- . Lower toxicity for the MWWTP effluent was obtained after oxidative treatments using hydrogen peroxide or monopersulfate as oxidants which react mainly through HO• radicals. Two mechanistic pathways were proposed for tebuthiuron degradation: (i) hydrogen abstraction by HO• (H2 O2 and HSO5 - ) and (ii) electron transfer by SO4 •- (S2 O8 2- ). In addition, one unprecedented transformation product was identified. In conclusion, results emphasize the relevance of comparing the degradation of toxic compounds in the presence of different peroxide sources and matrices and simultaneouly evaluating responses chemical and biological endpoints., Competing Interests: Declaration of competing interest There are no conflicts to declare., (Copyright © 2022 Elsevier B.V. All rights reserved.)- Published
- 2023
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9. Paper-based colorimetric sensor array for the rapid and on-site discrimination of green tea samples based on the flavonoid composition.
- Author
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Gomes JS, de Sousa RMF, and Petruci JFDS
- Subjects
- Antioxidants analysis, Flavonoids analysis, Principal Component Analysis, Colorimetry methods, Tea
- Abstract
Green tea is a worldwide appreciated food product with Chinese production estimated to reach over 3m tons in 2027 and with many valuable health effects. The development of analytical methods to discriminate among green tea samples is induced by economic benefits and to avoid deliberate origin mislabeling and adulteration. In this study, we present a paper-based colorimetric sensor array comprised of six ordinary reagents tailored for the discrimination of green tea extracts of different brands according to differences in the composition of flavonoids. The colorimetric array was rationally designed based on indicators that differentially react with a variety of flavonoids via specific functional groups. 4 μL of each reagent was impregnated onto the paper surface followed by the addition of the green tea extract. After 1 minute, digital images were acquired using a smartphone and the color changes were employed to build differential maps with a unique fingerprint for each green tea sample. Moreover, principal component analysis (PCA) and hierarchical component analysis (HCA) were employed to successfully discriminate among the samples, enabling the origin and adulteration identification of the samples. Therefore, this study provides a simple, effective, low-cost, and portable method for quick discrimination and quality control of green tea samples.
- Published
- 2022
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10. Identification of Substances Produced by Cercospora brachiata in Absence of Light and Evaluation of Antibacterial Activity.
- Author
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Felisbino JKRP, Vieira BS, de Oliveira A, da Silva NA, Martins CHG, Santiago MB, Munoz RAA, Cunha LCS, and Sousa RMF
- Abstract
Cercospora brachiata is a phytopathogenic fungus. To know more about the metabolites produced by this fungus, the objective of this work was to identify, isolate and characterize substances present in extracts of the growth broth and mycelium, using gas chromatography with mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR). It was also objective to evaluate the antibacterial activity of the extracts. Among the compounds identified, fatty acids, esters, and steroids can be highlighted. The main compounds identified are 9-hexadecenoic, hexadecenoic, oleic, octadecanoic, lauric, myristic, palmitic, doceno-13-enoic, stearic, linoleic, and nonadecanoic acids present in almost all extracts. For the antibacterial activity, the broth microdilution method was used. The ethyl acetate extract of the mycelium presented inhibitory concentrations (MICs) against the bacterium Actinomyces naeslundii (100 μg mL
-1 ) and Streptococcus sanguinis (200 μg mL-1 ). Finally, two steroids were isolated and identified in the hexane extract of mycelium: ergosta-6,22-dien-3β,5α,8α-triol and brassicasterol.- Published
- 2021
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11. Chemical and toxicological evaluation along with unprecedented transformation products during photolysis and heterogeneous photocatalysis of chloramphenicol in different aqueous matrices.
- Author
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Marson EO, Paniagua CES, Costa-Serge NM, Sousa RMF, Silva GD, Becker RW, Sirtori C, Starling MCVM, Carvalho SR, and Trovó AG
- Subjects
- Kinetics, Photolysis, Water, Chloramphenicol, Water Pollutants, Chemical analysis
- Abstract
As the presence of antibiotics in environmental waters enhances antimicrobial resistance, photolysis and heterogeneous photocatalysis of chloramphenicol (CAP) were evaluated in deionized water (DW) and in sewage treatment plant (STP) effluent under black light and solar irradiation. Processes were compared in terms of CAP degradation, reaction kinetics, and electrical energy per order, as well as regarding theoretical toxicity, biodegradability, carcinogenicity, and mutagenicity of transformation products (TPs). Rate constants obtained under photolysis (0.008 min
-1 ) and heterogeneous photocatalysis (0.18 min-1 ) only differed in DW. This is due to the generation of photo-active reactive oxygen species (HO· and HO2 ·- /O2 ·- ) under photolysis in STP effluent, as verified by experiments in the presence of 2-propanol and chloroform. Natural organic matter and HCO3 - were the main responsible for reducing CAP degradation in STP effluent. Fifteen TPs were identified during both processes in DW, 13 of which are unprecedented. TPs were formed mainly via HO· preferential attack on the aromatic ring and on the α-carbon, and some of them were classified as persistent and toxic, genotoxic, or carcinogenic by Toxtree software. Results confirm that solar photocatalysis is less costly than to photocatalysis under black light for wastewater treatment.- Published
- 2021
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12. Antioxidant compounds from Banisteriopsis argyrophylla leaves as α-amylase, α-glucosidase, lipase, and glycation inhibitors.
- Author
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Quaresma DMO, Justino AB, Sousa RMF, Munoz RAA, de Aquino FJT, Martins MM, Goulart LR, Pivatto M, Espindola FS, and de Oliveira A
- Subjects
- Antioxidants pharmacology, Catechin chemistry, Catechin pharmacology, Cyclohexanones chemistry, Cyclohexanones pharmacology, Drug Evaluation, Preclinical, Enzyme Inhibitors pharmacology, Flavonoids chemistry, Flavonoids pharmacology, Glucosides chemistry, Glucosides pharmacology, Glycosylation, Humans, Hypoglycemic Agents chemistry, Kaempferols chemistry, Kaempferols pharmacology, Lipase metabolism, Norisoprenoids chemistry, Norisoprenoids pharmacology, Plant Extracts pharmacology, Proanthocyanidins chemistry, Proanthocyanidins pharmacology, Antioxidants chemistry, Banisteriopsis chemistry, Enzyme Inhibitors chemistry, Plant Extracts chemistry, Plant Leaves chemistry, alpha-Amylases antagonists & inhibitors, alpha-Glucosidases metabolism
- Abstract
Banisteriopsis argyrophylla belongs to the Malpighiaceae family, which is a species from Cerrado, also known as "cipó-prata" or "cipó-folha-de-prata." Several species of this family present biological potential. This work reports the chemical identification of the ethanol extract (EE) and its fractions from B. argyrophylla leaves and shows the analysis of the antioxidant activity and inhibitory effects on activities of α-amylase, α-glucosidase and lipase, and non-enzymatic glycation. The ethyl acetate fraction (EAF) and n-butanol fraction (BF) showed antioxidant activity, with IC
50 values of 4.1 ± 0.1 and 4.8 ± 0.1 μg mL-1 , respectively, by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method, and IC50 values of 6046.3 ± 174.2 and 6264.2 ± 32.2 µmol Trolox eq g-1 by the oxygen radical absorbance capacity (ORAC) method. Furthermore, the DPPH method with these fractions presented electroactive species with antioxidant potential, as shown by the differential pulse voltammetry (DPV) method. The inhibitory effects of the EAF and BF were demonstrated by the following results: IC50 of 5.1 ± 0.3 and 2.5 ± 0.2 μg mL-1 for α-amylase, IC50 of 1093.5 ± 26.0 and 1250.8 ± 21.9 μg mL-1 for α-glucosidase, IC50 of 8.3 ± 4.1 and 4.4 ± 1.0 μg mL-1 for lipase, and IC50 of 1.3 ± 0.1 and 0.9 ± 0.1 μg mL-1 for glycation. Some bioactive compounds were identified by (-)-ESI-MS/MS, such as catechin, procyanidins, glycosylated flavonoids, kaempferol, and megastigmane glucosides. The antidiabetic activity of B.argyrophylla has been reported for the first time., (Copyright © 2020 Elsevier Inc. All rights reserved.)- Published
- 2020
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13. Dehydrodieugenol B and hexane extract from Endlicheria paniculata regulate inflammation, angiogenesis, and collagen deposition induced by a murine sponge model.
- Author
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Souza RAC, Ferreira BA, Moura FBR, Costa Silva TD, Cavalcanti F, Franca EF, Sousa RMF, Febronio JL, Lago JHG, Araújo FA, and de Oliveira A
- Subjects
- Angiogenesis Inhibitors pharmacology, Animals, Anisoles isolation & purification, Anti-Inflammatory Agents isolation & purification, Antifibrinolytic Agents isolation & purification, Brazil, Collagen metabolism, Hexanes, Inflammation drug therapy, Male, Mice, Mice, Inbred C57BL, Molecular Docking Simulation, Molecular Structure, Phytochemicals isolation & purification, Plant Leaves chemistry, Anisoles pharmacology, Anti-Inflammatory Agents pharmacology, Antifibrinolytic Agents pharmacology, Lauraceae chemistry, Phytochemicals pharmacology, Plant Extracts pharmacology
- Abstract
The present study reports the evaluation of hexane extract from Endlicheria paniculata and its main metabolite dehydrodieugenol B in the inflammatory response induced by a murine implant sponge model. As a result, a reduction in the inflammatory markers (myeloperoxidase and N-acetyl-β-D-glucosaminidase) and number of mast cells were observed in comparison to the control group. All doses were also able to reduce angiogenic parameters evaluated in fibrovascular tissue. In implants treated with dehydrodieugenol B a reduction in total collagen deposition and types I and III collagen fibers were observed, while an increased in total collagen deposition and types I and III collagen fibers were observed in the treatment with hexane extract. Docking studies into cyclooxygenase-2 active site revealed that the dehydrodieugenol B had binding modes and energies comparable with celecoxib, diclofenac and ibuprofen. Therefore, dehydrodieugenol B was able to alter key components of chronic inflammation, resulting in a reduced inflammatory response and also presenting antifibrogenic and antiangiogenic effects. However, treatment with hexane extract resulted in a reduced inflammatory response with antiangiogenic effects, but caused fibrogenic effects., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2020
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14. Degradation mechanism of fipronil and its transformation products, matrix effects and toxicity during the solar/photo-Fenton process using ferric citrate complex.
- Author
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Gomes Júnior O, Batista LL, Ueira-Vieira C, Sousa RMF, Starling MCVM, and Trovó AG
- Subjects
- Animals, Drosophila melanogaster, Ferric Compounds, Oxidation-Reduction, Pyrazoles, Hydrogen Peroxide, Water Pollutants, Chemical
- Abstract
This study presents the degradation of fipronil in sewage treatment plant (STP) effluent by photo-Fenton at near neutral pH (pH 6.0) using Fe
3+ /Citrate complex. 83% of fipronil degradation was reached using a molar iron/citrate ratio of 1:3 (192 μmol L-1 of Fe3+ /576 μmol L-1 of citrate). Photo-Fenton reduced the toxicity of treated solutions as according to the survival of Drosophila melanogaster exposed to non-treated and treated samples. Control experiments performed in distilled water using 32 μmol L-1 of Fe3+ /96 μmol L-1 of citrate achieved 98% of fipronil degradation within 100 kJ m-2 (UV-A radiation, k = 30 × 10-3 kJ-1 m2 and t1/2 = 23 kJ m-2 ), thus indicating that fipronil degradation is impaired by natural organic matter and inorganic ions present in STP effluent. Degradation was faster under solar radiation, as the same efficiency (98%) was obtained after 75 kJ m-2 (k = 63 × 10-3 kJ-1 m2 and t1/2 = 11 kJ m-2 ). In addition, pathways of fipronil degradation using Fe3+ /Citrate under solar and UV-A radiation were investigated and transformation products proposed. Results revealed that the HO• attack occurred preferentially in the pyrazole ring. Eight transformation products were identified by UHPLC-Q-TOF-MS and four are unprecedented in the literature. Control experiments in distilled water demonstrated that toxicity reduction is related to fipronil degradation and that transformation products are less toxic than fipronil. Furthermore, toxicity of STP fortified with fipronil was reduced after photo-Fenton. These results demonstrate the feasibility of applying this process using Fe3+ /Citrate complex for fipronil degradation in a real matrix., Competing Interests: Declaration of competing interest There are no conflicts to declare., (Copyright © 2020 Elsevier Ltd. All rights reserved.)- Published
- 2020
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15. Investigation of midazolam electro-oxidation on boron doped diamond electrode by voltammetric techniques and density functional theory calculations: Application in beverage samples.
- Author
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Rocha RG, Silva WP, Sousa RMF, Junior MC, Santana MHP, Munoz RAA, and Richter EM
- Abstract
Midazolam (MID) is a sedative drug which can be added in beverage samples as drug-facilitated-sexual assault (date rape drug). This type of drug has short half-life in biological fluids (not detectable) which often prevents the correlation between drug abuse and crime. In this work, we described a simple and low-cost method for fast screening and selective determination of MID in beverage samples (vodka, whiskey and red wine). For the first time, the electrochemical oxidation of MID was used for this purpose. The oxidation mechanism was studied using electrochemical techniques (cyclic and square-wave voltammetry) and computational simulations (density functional theory calculations). Differential-pulse voltammetry, boron-doped diamond electrode (BDDE), and Britton-Robinson (BR) buffer (pH = 2) were selected as electrochemical analysis technique, working electrode and supporting electrolyte, respectively. Different linear response ranges (4-25 μmol L
-1 with r = 0.9972; 1-10 μmol L-1 with r = 0.9951; 1-15 μmol L-1 with r = 0.9982) and limits of detection (0.46, 0.43 and 0.33 μmol L-1 ) were obtained for the analysis of vodka, whisky, and red wine solutions, respectively. The precision and accuracy were satisfactory considering the low relative standard deviation values (RSD < 6.3%, n = 15) and minimal sample matrix effects (recovery values between 87 and 103%)., (Copyright © 2019 Elsevier B.V. All rights reserved.)- Published
- 2020
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16. B procyanidins of Annona crassiflora fruit peel inhibited glycation, lipid peroxidation and protein-bound carbonyls, with protective effects on glycated catalase.
- Author
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Justino AB, Franco RR, Silva HCG, Saraiva AL, Sousa RMF, and Espindola FS
- Subjects
- Animals, Antioxidants pharmacology, Biflavonoids chemistry, Catechin chemistry, Cattle, Cell Line, Cell Survival drug effects, Cross-Linking Reagents chemistry, Fluorescence, Glycation End Products, Advanced metabolism, Glycosylation, Phenols analysis, Proanthocyanidins chemistry, Reactive Oxygen Species metabolism, Serum Albumin, Bovine metabolism, Sulfhydryl Compounds metabolism, Annona chemistry, Biflavonoids pharmacology, Catalase metabolism, Catechin pharmacology, Fruit chemistry, Lipid Peroxidation drug effects, Phytochemicals pharmacology, Proanthocyanidins pharmacology, Protective Agents pharmacology, Protein Carbonylation drug effects
- Abstract
Advanced glycation end-products (AGEs) have been reported as results of increased oxidative stress. Consequently, the search for new antioxidant and anti-glycating agents is under intense investigation. Plant-derived procyanidins have previously demonstrated anti-glycation properties. Thus, this study aimed to isolate procyanidins from Annona crassiflora fruit peel, a species from the Brazilian Savanna, and investigate their antioxidant and anti-glycation effects. Free radical scavenging and quenching properties, formation of reactive oxygen species (ROS), AGEs, protein carbonyl and thiol groups, lipid peroxidation, crosslinked AGEs, as well as glycated catalase activity, were analyzed. In addition, in silico assessment of absorption, distribution, metabolism, excretion and toxicity was carried out. The procyanidins-enriched fraction, named here as F7, showed high antioxidant and anti-glycation capacities, with inhibitory activities against lipid peroxidation, and AGEs and ROS formation. In addition, there were reductions in AGEs-induced crosslinks and protein carbonyls and protective effects against oxidation of thiol groups and glycated-catalase. ADMET predictions of F7 showed favorable absorption and distribution, with no hepatotoxicity or mutagenicity. Together, our results support the anti-glycation activities of the procyanidins-enriched fraction from A. crassiflora, and suggest that these effects are triggered, at least in part, by scavenging free radical and dicarbonyls intermediates.
- Published
- 2019
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17. Polymeric blends of hydrocolloid from chia seeds/apple pectin with potential antioxidant for food packaging applications.
- Author
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Silva ISVD, Sousa RMF, Oliveira A, Oliveira WJ, Motta LAC, Pasquini D, and Otaguro H
- Abstract
The aim of this study was to investigate the antioxidant, mechanical and physical properties of a new film-based polymeric blend of hydrocolloids obtained from the aqueous extraction of chia seeds (source antioxidants) and apple pectin. The individual matrices films were brittle and rigid with poor mechanical properties. The blends formulations contributed to improved mechanical properties regarding workability and resistance. The antioxidant results showed the potential hydrocolloid from chia seeds as natural source of antioxidant in these polymeric films. The formulation 3 (14(hydrocolloid):41(pectin):25(glycerol):20(glutaraldehyde) displayed well thermal, mechanical, morphological and antioxidant properties, suggesting their great potential for food packaging., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
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18. Integrating coagulation-flocculation and UV-C or H 2 O 2 /UV-C as alternatives for pre- or complete treatment of biodiesel effluents.
- Author
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Costa NM, Silva VM, Damaceno G, Sousa RMF, Richter EM, Machado AEH, and Trovó AG
- Subjects
- Brazil, Flocculation, Oxidation-Reduction, Ultraviolet Rays, Water Pollutants, Chemical, Biofuels, Hydrogen Peroxide, Waste Disposal, Fluid
- Abstract
The feasibility of biodiesel effluent treatment combining coagulation-flocculation with a photolytic process was evaluated, being the photolytic process involving the irradiation of the effluent by UV-C, or by UV-C irradiation with simultaneous addition of H
2 O2 (H2 O2 /UV-C). The coagulation-flocculation was performed at the natural pH of the effluent (pH 2.9) using different Fe3+ salts (chloride, nitrate and sulfate) at different concentrations (0.25, 0.50 and 1.0 mmol L-1 ) of the counterions. The best results were achieved using 0.50 mmol L-1 Fe(NO3 )3 . Following, the degradation of the organic load and toxicity reduction of the pre-treated effluent by UV-C irradiation was evaluated. The H2 O2 /UV-C process showed to be advantageous, mainly when multiple additions of H2 O2 were used during the course of the reaction. Additionally, the influence of the initial pH on the degradation was also evaluated. A high level of mineralization (94%) was achieved after 6 h of irradiation concomitantly with multiple additions of 2,000 mg L-1 H2 O2 , and with the effluent at the natural pH. Thus, using coagulation-flocculation followed by the H2 O2 /UV-C process, it was possible to achieve a favourable condition for reuse of the pre-treated effluent, since, in addition to the significant reduction of the organic load, the final DBO5 (<120 mg L-1 ) and oils & fats (<50 mg L-1 ) are below the limits established by the Brazilian legislation. Furthermore, a reduction of 78% of acute toxicity to V. fischeri (from 89% to 20%) was reached. The results suggest, therefore, that this process is a viable option for treatment of this kind of effluent., (Copyright © 2017 Elsevier Ltd. All rights reserved.)- Published
- 2017
- Full Text
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19. Phytochemical characterization of the Vochysia rufa (Vochysiaceae) extract and its effects on oxidative stress in the pancreata of streptozotocin-induced diabetic rats.
- Author
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de Gouveia NM, Rodrigues WF, de Sousa RMF, Calábria LK, Mundim AV, Miguel CB, Oliveira CJF, Lazo-Chica JE, de Oliveira A, Lago JHG, Dos Santos VB, do Lago CL, and Espindola FS
- Subjects
- Animals, Blood Glucose, Body Weight drug effects, Catalase metabolism, Glutathione metabolism, Male, Pancreas metabolism, Rats, Rats, Wistar, Superoxide Dismutase metabolism, Thiobarbituric Acid Reactive Substances metabolism, Antioxidants pharmacology, Diabetes Mellitus, Experimental metabolism, Magnoliopsida, Oxidative Stress drug effects, Pancreas drug effects, Phytotherapy, Plant Extracts pharmacology
- Abstract
Aqueous extract of macerated Vochysia rufa stem bark has been commonly used in the treatment of diabetes. Therefore, we evaluated the antihyperglycemic and antioxidant effects of an extract of V. rufa on the pancreata of streptozotocin (STZ)-induced diabetic rats. Animals received one of the following treatments daily by oral gavage: water (diabetic-control), V. rufa extract (diabetic-V. rufa), or glibenclamide (diabetic-GBD). Total antioxidant capacity; levels of thiobarbituric acid reactive substances, reduced glutathione, and sulfhydryls; and superoxide dismutase, catalase, and glutathione peroxidase (GPx) activities were measured in the pancreas. Biochemical analysis of serum total cholesterol and fractions, triglycerides, creatinine, urea, acid uric, ALP, γ-GT, AST, and ALT was performed, and pancreatic β-cells positive for insulin were evaluated by immunohistochemistry. Rats treated with extract exhibited a decrease in fasting blood glucose compared with levels in diabetic control rats. GPx activity and sulfhydryl levels were significantly lower in diabetic-V. rufa rats compared with those of diabetic-control rats. V. rufa extract acted to normalize the biochemical alterations found in diabetic rats (diabetic-controls), as demonstrated by increases in urea, HDL, ALP, AST, and ALT. Reduction in blood glucose was independent of an increase in insulin. The V. rufa extract was found to be composed of free sugars (inositol, galactose, glucose, mannose, sucrose, arabinose, and ribose) as the main metabolites. Thus, aqueous extract of the stem bark of V. rufa is capable of reducing blood glucose, resulting in an antioxidant effect on the pancreatic tissue of STZ-diabetic rats.
- Published
- 2017
- Full Text
- View/download PDF
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