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1.
Molecules ; 28(14)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37513277

RESUMO

Gallesia integrifolia, a notable species in the Atlantic Forest, has been traditionally employed in folk medicine for treating rheumatism, asthma, and worms. This study investigated the cellular antioxidant, antiproliferative, and anti-inflammatory activities of the essential oils (EOs) and crude extracts (CEs) from G. integrifolia flowers, fruits, and leaves. The chemical identification of EOs was performed by GC-MS and CEs by UHPLC-MS. Cellular antioxidant and anti-inflammatory activities were assessed through mouse macrophage cell culture. In addition, the antiproliferative potential was evaluated in gastric, colorectal, breast, and lung tumor cell lines and non-tumor VERO cells. EOs predominantly contained organosulfur compounds in flowers (96.29%), fruits (94.94%), and leaves (90.72%). We found the main compound is 2,2'-Disulfanediyldiethanethiol in the EOs of flowers (47.00%), leaves (41.82%), and fruits (44.39%). Phenolic compounds were identified in CEs. The EOs and CEs demonstrated potential against the tumor cell lines tested (GI50 between 51 and 230 µg/mL). The selectivity index values were greater than 1.0 (1.01 to 3.37), suggesting a relative safety profile. Moreover, the anti-inflammatory activity IC50 ranged from 36.00 to 268 µg/mL, and the cellular oxidation inhibition ranged from 69% to 82%. The results suggest that oils and extracts derived from G. integrifolia have potential for use in various industrial sectors.


Assuntos
Antioxidantes , Óleos Voláteis , Camundongos , Animais , Chlorocebus aethiops , Antioxidantes/farmacologia , Antioxidantes/análise , Frutas , Células Vero , Folhas de Planta/química , Flores/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/análise , Óleos Voláteis/química , Extratos Vegetais/química
2.
Trop Med Infect Dis ; 8(7)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37505671

RESUMO

Human tegumentary leishmaniasis (HTL) is a serious tropical disease caused by Leishmania amazonensis. Developing new leishmanicidal agents can help overcome current treatment challenges, such as drug resistance and toxicity. Essential oils are a source of lipophilic substances with diverse therapeutic properties. This study aimed to determine the anti-L. amazonensis activity, cytotoxicity, and chemical profile of Allium sativum essential oil (ASEO). The effect of ASEO on parasite and mammalian cells viability was evaluated using resazurin and MTT assays, respectively. The oil's effect against intracellular amastigotes was also determined. Transmission electron microscopy was used to assess the ultrastructural changes induced by ASEO. In addition, the chemical constituents of ASEO were identified by gas chromatography-mass spectrometry (GC-MS). The cytotoxic potential was evaluated in vitro and in silico. The oil displayed IC50 of 1.76, 3.46, and 3.77 µg/mL against promastigotes, axenic, and intracellular amastigotes, respectively. Photomicrographs of treated parasites showed plasma membrane disruption, increased lipid bodies, and autophagic-like structures. ASEO chemical profiling revealed 1,2,4,6-tetrathiepane (24.84%) and diallyl disulfide (16.75%) as major components. Computational pharmacokinetics and toxicological analysis of ASEO's major components demonstrated good oral bioavailability and better toxicological endpoints than the reference drugs. Altogether, the results suggest that ASEO could be an alternative drug candidate against HTL.

3.
Gene ; 877: 147506, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37224934

RESUMO

Bacteria can communicate to each other via quorum sensing, a cell density-dependent gene regulation system that stimulates the expression of virulence factors in the neighboring cells. Although the interaction of the natural product ajoene with the Hfq protein has been associated with the disruption of the quorum sensing system in Pseudomonas aeruginosa, there is no information concerning the corresponding ligand-target interaction process. Herein we observed a strong correlation (p < 0.00001) between the estimated affinities for the binding of 23 ajoene analogues at the proximal site of the Hfq protein of P. aeruginosa and their corresponding IC50 values, which reflect the reduction in the transcription of a virulence factor after quorum sensing inhibition. In this concern, our analyses reinforces previous propositions suggesting that ajoene could target the Hfq protein and affects its interaction with RNAs. Based on docking simulations, we tried to elucidate the binding mode of ajoene into the proximal Hfq site and we also established the minimum set of groups that would be necessary for a good interaction at this site, which includes a single hydrogen bond acceptor feature surrounded by groups that interact via π-sulfur (i.e., disulfide sulfurs) and/or π-alkyl/π-π stacking interactions (e.g., vinyl or small aryl/heteroaryl/heterocyclic groups). Because of the widespread role of Hfq as a matchmaker between messenger and small regulatory RNAs in Gram-negatives, we believe the discussion here provided for P. aeruginosa could be extrapolated for Gram-negatives in general, while the interaction of ajoene over the Hfq protein of Gram-positives would still remain more controversial.


Assuntos
Pseudomonas aeruginosa , Percepção de Quorum , Percepção de Quorum/genética , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , RNA/metabolismo , Dissulfetos/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica
4.
Molecules ; 27(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36500312

RESUMO

Thermal processing of certain foods implies the formation of acrylamide, which has been proven to provoke adverse effects on human health. Thus, several strategies to mitigate it have been developed. One of them could be the application of organosulfur compounds obtained from natural sources to react with the acrylamide, forming non-toxic adducts. A DFT study of the acrylamide reaction with the organosulfur model compounds L-cysteine and L-glutathione by Michael addition and a free radical pathway complemented by a kinetic study of these model molecules has been applied. The kinetic evaluation results demonstrate that the L-glutathione reaction exhibited a higher rate constant than the other studied compound.


Assuntos
Acrilamida , Cisteína , Humanos , Acrilamida/metabolismo , Cisteína/metabolismo , Glutationa
5.
Microbiol Spectr ; 9(3): e0017021, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34817207

RESUMO

Prenatal screening in pregnant women between 35 and 37 weeks of gestation and intrapartum antibiotic prophylaxis has successfully reduced the incidence of neonatal morbidity and mortality related to Streptococcus agalactiae. However, the contamination rates of newborns are still considerable. In traditional and folk medicines, it has been observed that garlic has been effective in treating S. agalactiae infection. The aim of this study was to isolate and identify the active compounds from garlic that have antimicrobial activity against S. agalactiae. In order to do this, SP80 (Sep-Pak 80%) obtained from crude garlic extract (CGE) was fractionated by reverse-phase ultrafast liquid chromatography with UV (RP-UFLC-UV) using a Shim-pack PREP-ODS column. All fractions obtained were tested using a microbial growth inhibition test against the S. agalactiae strain (ATCC 12386). Five clinical isolates were used to confirm the action of the fractions with antimicrobial activity, and the bacterial growth curve was determined. Identification of the antimicrobial compounds was carried out through liquid chromatography coupled with mass spectrometry (LC/MS) and nuclear magnetic resonance (NMR). The active compounds found to exhibit antimicrobial activity were Ƴ-glutamyl-S-allyl-cysteine (fraction 18), Ƴ-glutamyl-phenylalanine (fraction 20), and the two stereoisomers (E and Z) of ajoene (fraction 42). The MICs of these fractions were 5.41 mg/ml, 4.60 mg/ml, and 0.16 mg/ml, respectively, and they inhibited the growth of the clinical isolates tested. Antimicrobial compounds from garlic may be a promising source in the search for new drugs against S. agalactiae. IMPORTANCE Invasive disease due to group B streptococcal (GBS) infection results in a wide spectrum of clinical disease in neonates. Maternal colonization by GBS is the primary risk factor for disease. The strategy recommended by the Centers for Disease Control to reduce neonatal GBS infection is the culture-based screening of all pregnant women at 35 to 37 weeks of gestation and intrapartum antibiotic prophylaxis (IAP). However, indiscriminate use of antibiotics favors the selection and spread of resistant bacteria. The global scenario of antibacterial resistance has been of great concern for public health, and natural products can be a source of new substances to help us grapple with this problem.


Assuntos
Antibacterianos/farmacologia , Alho/química , Extratos Vegetais/farmacologia , Infecções Estreptocócicas/microbiologia , Streptococcus agalactiae/efeitos dos fármacos , Antibacterianos/química , Cromatografia Líquida de Alta Pressão , Avaliação Pré-Clínica de Medicamentos , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Infecções Estreptocócicas/tratamento farmacológico , Streptococcus agalactiae/genética , Streptococcus agalactiae/fisiologia
6.
Front Chem ; 9: 690707, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616711

RESUMO

Among healthy vegetables, those of the genus Allium stand out. Antioxidant and anti-inflammatory properties have been associated with these vegetables, attributed mainly to organosulfur compounds (OSCs). In turn, they are linked to a protective effect counteracting cardiovascular disease development. Now, to really ensure the bioactive efficacy of the said compounds once consumed, it is necessary to previously evaluate the ADME (absorption, distribution, metabolism, and excretion) profile. Alternatively, in vitro and in silico methods attempt to avoid or reduce experimental animals' use and provide preliminary information on drugs' ability to overcome the various biological barriers inherent in the ADME process. In this sense, in silico methods serve to provide primary information on drugs' bioavailability mechanisms. High-performance liquid chromatography (HPLC) using a stationary phase composed of phospholipids, the so-called immobilized artificial membrane (IAM), has been widely recognized as a valuable alternative method to extract and quantify information about the structure and physicochemical properties of organic compounds which are extensively used in studies of quantitative structure-activity relationships (QSARs). In the present study, the chromatographic capacity factors (log k' (IAM)) for 28 OSCs were determined by IAM-HPLC. In order to evaluate the ability of the IAM phase in assessing lipophilicity of the compounds under study, several quantitative structure-retention relationships (QSRRs) were derived from exploring fundamental intermolecular interactions that govern the retention of compounds under study on IAM phases. As expected, the hydrophobic factors are of prime importance for the IAM retention of these compounds. However, the molecular flexibility and specific polar interactions expressed by several electronic descriptors (relative negative charge, RNCG, and Mulliken electronegativity) are also involved. We also evaluated the IAM phase ability to assess several ADME parameters for the OSCs under study obtained using the SwissADME web tool integrated into the SwissDrugDesign workspace and the PreADMET web tool. The human gastrointestinal absorption (HIA), blood-brain barrier (BBB) permeation, and skin permeability were investigated through QSAR modeling, using several chemometric approaches. The ADME properties under study are strongly dependent on hydrophobic factors as expressed by log k'(IAM), which provide evidence for the great potential of the IAM phases in the development of QSAR models.

7.
Antioxidants (Basel) ; 11(1)2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-35052552

RESUMO

Garlic (Allium sativum) has been used in alternative medicine to treat several diseases, such as cardiovascular and neurodegenerative diseases, cancer, and hepatic diseases. Several publications have highlighted other features of garlic, including its antibacterial, antioxidative, antihypertensive, and antithrombotic properties. The properties of garlic result from the combination of natural compounds that act synergistically and cause different effects. Some garlic-derived compounds have been studied for the treatment of several types of cancer; however, reports on the effects of garlic on neuroblastoma are scarce. Neuroblastoma is a prevalent childhood tumor for which the search for therapeutic alternatives to improve treatment without affecting the patients' quality of life continues. Garlic-derived compounds hold potential for the treatment of this type of cancer. A review of articles published to date on some garlic compounds and their effect on neuroblastoma was undertaken to comprehend the possible therapeutic role of these compounds. This review aimed to analyze the impact of some garlic compounds on cells derived from neuroblastoma.

8.
Microbiol Spectr, v. 9, n. 3, e00170-21, nov. 2021
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4007

RESUMO

Prenatal screening in pregnant women between 35 and 37 weeks of gestation and intrapartum antibiotic prophylaxis has successfully reduced the incidence of neonatal morbidity and mortality related to Streptococcus agalactiae. However, the contamination rates of newborns are still considerable. In traditional and folk medicines, it has been observed that garlic has been effective in treating S. agalactiae infection. The aim of this study was to isolate and identify the active compounds from garlic that have antimicrobial activity against S. agalactiae. In order to do this, SP80 (Sep-Pak 80%) obtained from crude garlic extract (CGE) was fractionated by reverse-phase ultrafast liquid chromatography with UV (RP-UFLC-UV) using a Shim-pack PREP-ODS column. All fractions obtained were tested using a microbial growth inhibition test against the S. agalactiae strain (ATCC 12386). Five clinical isolates were used to confirm the action of the fractions with antimicrobial activity, and the bacterial growth curve was determined. Identification of the antimicrobial compounds was carried out through liquid chromatography coupled with mass spectrometry (LC/MS) and nuclear magnetic resonance (NMR). The active compounds found to exhibit antimicrobial activity were Ƴ-glutamyl-S-allyl-cysteine (fraction 18), Ƴ-glutamyl-phenylalanine (fraction 20), and the two stereoisomers (E and Z) of ajoene (fraction 42). The MICs of these fractions were 5.41 mg/ml, 4.60 mg/ml, and 0.16 mg/ml, respectively, and they inhibited the growth of the clinical isolates tested. Antimicrobial compounds from garlic may be a promising source in the search for new drugs against S. agalactiae

9.
Plant Foods Hum Nutr ; 75(3): 355-361, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32388808

RESUMO

Organosulfur compounds (OSCs) of garlic have various health benefits including anti-hypertensive effect. It has been described that volatile OSCs uptake occurs into a moderate extent. Among the bioavailable OSCs present in garlic, 2-vinyl-4H-1,3-dithiin (2VD) is a main component in garlic macerated oil and stir-fried garlic but has been poorly investigated compared with others OSCs, such allyl mercaptan (AM) and S-allyl cysteine (SAC). The aim of this study was to evaluate the effects of 2VD on vascular smooth muscle cells (VSMCs) isolated from spontaneous hypertensive rats (SHR) and compare them with those produced by AM and SAC. Cell viability and proliferation were measured using tetrazolium dye MTT assay and flow cytometry. Cell migration was evaluated by scrape-wound migration assay. OSCs anti-oxidative capacity was determined by measuring reactive oxygen species (ROS) generation, and total antioxidant status (TAS). Non-toxic plasmatic concentrations (10 µg L-1) of 2VD and AM inhibited VSMCs proliferation stimulated with 5% fetal bovine serum and impaired cell migration. In further flow cytometry analysis 2VD treatment resulted in a partial cell cycle arrest at G2 phase. The OSCs tested were able to prevent ROS increase after angiotensin II stimulation and surprisingly 2VD induced higher total antioxidant status compared with AM and SAC. Our results showed that 2VD produces equivalent or superior beneficial effects on VSMCs to those reported for other bioavailable compounds of garlic. This preliminary evidence suggests that 2VD intake could also exert important protective effects against arterial remodeling in hypertension.


Assuntos
Alho , Animais , Antioxidantes , Proliferação de Células , Compostos Heterocíclicos , Músculo Liso Vascular , Estresse Oxidativo , Ratos , Compostos de Enxofre , Compostos de Vinila
10.
Life Sci ; 249: 117513, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32145307

RESUMO

According to investigations in phytomedicine and ethnopharmacology, the therapeutic properties of garlic (Allium sativum) have been described by ancestral cultures. Notwithstanding, it is of particular concern to elucidate the molecular mechanisms underlying this millenary empirical knowledge. Allicin (S-allyl prop-2-ene-1-sulfinothioate), a thioester of sulfenic acid, is one of the main bioactive compounds present in garlic, and it is responsible for the particular aroma of the spice. The pharmacological attributes of allicin integrate a broad spectrum of properties (e.g., anti-inflammatory, immunomodulatory, antibiotic, antifungal, antiparasitic, antioxidant, nephroprotective, neuroprotective, cardioprotective, and anti-tumoral activities, among others). The primary goal of the present article is to review and clarify the common molecular mechanisms by which allicin and its derivates molecules may perform its therapeutic effects on cardiovascular diseases and neuroinflammatory processes. The intricate interface connecting the cardiovascular and nervous systems suggests that the impairment of one organ could contribute to the dysfunction of the other. Allicin might target the cornerstone of the pathological processes underlying cardiovascular and neuroinflammatory disorders, like inflammation, renin-angiotensin-aldosterone system (RAAS) hyperactivation, oxidative stress, and mitochondrial dysfunction. Indeed, the current evidence suggests that allicin improves mitochondrial function by enhancing the expression of HSP70 and NRF2, decreasing RAAS activation, and promoting mitochondrial fusion processes. Finally, allicin represents an attractive therapeutic alternative targeting the complex interaction between cardiovascular and neuroinflammatory disorders.


Assuntos
Anti-Inflamatórios/uso terapêutico , Cardiotônicos/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Inflamação/tratamento farmacológico , Doenças do Sistema Nervoso/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Ácidos Sulfínicos/uso terapêutico , Dissulfetos , Humanos
11.
Curr Hypertens Rep ; 22(1): 6, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31925548

RESUMO

PURPOSE OF REVIEW: Several studies have attributed garlic's beneficial properties to its high content of organosulfur compounds (OSCs). Here, we summarized recent studies published and some own findings regarding OSCs and its effects on cardiovascular disease, inflammation, and obesity. RECENT FINDING: The analysis of the multiple actions produced by OSCs suggests that many of its bioactivities interfere against inflammation, oxidative stress, obesogenic effects, and mitochondrial dysfunction. Accumulating evidence from in vitro, animal, and human studies reinforce the notion that OSCs modify signaling pathways that trigger chronic diseases, and to highlight, actions over these pathways are related to the treatment of disorders addressed in this review. Garlic's bioactive OSCs behave like a nutraceutical panacea because they cover a broad spectrum of applications with promising impact for the prevention and treatment of prevalent chronic pathologies associated with low-grade inflammation.


Assuntos
Doenças Cardiovasculares , Alho , Hipertensão , Obesidade , Extratos Vegetais , Animais , Doenças Cardiovasculares/terapia , Humanos , Hipertensão/terapia , Inflamação , Obesidade/terapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
12.
Carbohydr Polym ; 219: 240-250, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151522

RESUMO

In this study, Schiff bases of chitosan (CS) were synthesized using citronellal, citral, and their derivatives containing selenium and sulfur. Organoselenium and organosulfur compounds show attractive biological and pharmaceutical activities, which can be beneficial to CS-based materials. From the characterization analyses, it was found that the CS-derivatives containing organoselenium and organosulfur compounds exhibited the highest conversion degrees (23 and 28%). Biological assays were conducted using films prepared by the blending of CS-derivatives and poly(vinyl alcohol). The antimicrobial evaluation indicated that the film prepared with the sulfur-containing CS was the most active against the tested pathogens (Escherichia coli, Staphylococcus aureus, and Candida albicans) since it reduced considerably their counts (42.5%, 17.4%, and 18.7%). Finally, in vivo assays revealed that this film attenuates atopic dermatitis-like symptoms in mice by suppressing the increase of myeloperoxidase (MPO) activity and reactive species (RS) levels induced by 2,4-dinitrochlorobenzene (DNCB). In summary, CS-derivatives containing chalcogens, mainly organosulfur, are potential candidates for biomedical applications such as for the treatment of chronic skin diseases.


Assuntos
Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Quitosana , Dermatite Atópica/tratamento farmacológico , Compostos Organosselênicos/farmacologia , Bases de Schiff/farmacologia , Animais , Candida albicans/efeitos dos fármacos , Calcogênios/farmacologia , Quitosana/análogos & derivados , Quitosana/farmacologia , Dermatite Atópica/induzido quimicamente , Dinitroclorobenzeno/química , Modelos Animais de Doenças , Escherichia coli/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Peroxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/efeitos dos fármacos
13.
ADMET DMPK ; 7(3): 196-209, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-35350661

RESUMO

CYP2A6 is a human enzyme responsible for the metabolic elimination of nicotine, and it is also involved in the activation of procarcinogenic nitrosamines, especially those present in tobacco smoke. Several investigations have reported that reducing this enzyme activity may contribute to anti-smoking therapy as well as reducing the risk of promutagens in the body. For these reasons, several authors investigate selective inhibitors molecules toward this enzyme. The aim of this study was to evaluate the interactions between a set of organosulfur compounds and the CYP2A6 enzyme by a quantitative structure-activity relationship (QSAR) analysis. The present work provides a better understanding of the mechanisms involved, with the final goal of providing information for the future design of CYP2A6 inhibitors based on dietary compounds. The reported activity data were modeled by means of multiple regression analysis (MLR) and partial least-squares (PLS) techniques. The results indicate that hydrophobic and steric factors govern the union, while electronic factors are strongly involved in the case of monosulfides.

14.
São Paulo; s.n; s.n; 2017. 166p ilus, tab.
Tese em Português | LILACS | ID: biblio-874966

RESUMO

Neste trabalho promovemos a síntese de sulfóxidos vinílicos ?-substituídos através da reação de acoplamento cruzado de Suzuki-Miyaura. Também foi feita a síntese de sulfóxidos enínicos inéditos, pela adição do nucleófilo no carbono ß-sulfóxido. Esses compostos eram passíveis de serem submetidos a reação de rearranjo de Pummerer aditivo e assim gerarem uma pequena biblioteca de compostos α-tioaldeídos. Um desses aldeídos sintetizados foi empregado na reação de formação de uma imina propargílica, com consequente reação de CuAAC formando iminas triazólicas. Outras iminas arílicas foram sintetizadas, passando por uma etapa de redução, com intuito de se obter a amina livre, para que fosse feita a reação de ciclização com auxílio de um agente eletrofílico. Outra classe de composto organoenxofre foi sintetizada, as N-sulfinil imina, que após a reação de acoplamento cruzado de Sonogashira, com consequente remoção de um grupo protetor e a formação do anel heterocíclico, foram obtidos compostos triazólicos N-sulfinil imínicos.


In this work we promote the synthesis of α-substituted vinylic sulfoxides through the Suzuki-Miyaura cross coupling reaction. Also the synthesis of unpublished enynic sulfoxides was made, by the addition of the nucleophile in the ß-sulfoxide carbon. These compounds were susceptible to additive Pummerer rearragement reaction and thus generated a small library of compounds. One of these aldehydes synthesized was used in the formation reaction of a propargyl imine, with consequent CuAAC reaction, forming triazol imines. Other aryl imines were synthesized, undergoing a reduction step, in order to obtain the free amine, so that the cyclization reaction was carried out with the aid of an electrophilic agent. Another class of organosulfur compound was synthesized, the N-sulfinyl imine, which after the Sonogashira cross-coupling reaction, with consequent removal of a protecting group and formation of the heterocyclic ring, N-sulfinyl imine triazolic compounds were obtained.


Assuntos
Iminas , Sulfetos , Sulfóxidos , Espectroscopia de Ressonância Magnética
15.
J Chromatogr A ; 1457: 29-40, 2016 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-27342135

RESUMO

We present a sensitive liquid chromatography-atmospheric pressure photoionization tandem mass spectrometric (UHPLC-APPI-MS/MS) method for the determination of selected organosulfur compounds in Brazilian asphalt cements. It was possible to detect 14 organosulfur compounds of different classes where sulfoxides and sulfones presented higher sensibility in ionization than thiophenes and aromatic sulfides. A dopant-assisted APPI method was also tested, however, when chromatographic flow rate was optimized a decrease in signal was observed for all compounds. PAHs were tested and ruled out as possible interfering compounds and the matrix effect of asphalt cements was within an acceptable range for the quantification of organosulfur compounds. The proposed method was found to have satisfactory linearity and accuracy with recoveries between 83.85 and 110.28% for thianaphthene and 3-methylbenzothiophene, respectively. Therefore, the method allowed the characterization of organosulfur compounds in Brazilian asphalt cements and demonstrated changes in the amount quantified in asphaltenic and maltenic fractions after the RTFOT+SUNTEST aging process.


Assuntos
Hidrocarbonetos/química , Petróleo/análise , Compostos de Enxofre/análise , Pressão Atmosférica , Brasil , Cromatografia Líquida de Alta Pressão/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Sulfetos/análise , Sulfonas/análise , Sulfóxidos/análise , Espectrometria de Massas em Tandem/métodos , Tiofenos/análise
16.
Chemistry ; 21(44): 15583-8, 2015 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-26367390

RESUMO

A simple approach to exfoliate and functionalize MoS2 in a single-step is described, which combines the dispersion of MoS2 in polybutadiene solution and ultrasonication processes. The great advantage of this process is that a colloidal stability of MoS2 in nonpolar solvent is achieved by chemically bonding polybutadiene on the perimeter edge sites of MoS2 sheets. In addition, elastomeric nanocomposite has been prepared with singular mechanical properties using functionalized MoS2 as nanofiller in a polybutadiene matrix with a subsequent vulcanization reaction.

17.
Neurochem Int ; 89: 83-91, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26122973

RESUMO

Therapeutic approaches based on isolated compounds obtained from natural products to handle central and peripheral disorders involving oxidative stress and inflammation are more common nowadays. The validation of nutraceutics vs. pharmaceutics as tools to induce preventive and protective profiles in human health alterations is still far of complete acceptance, but the basis to start more solid experimental and clinical protocols with natural products has already begun. S-allyl cysteine (SAC) is a promising garlic-derived organosulfur compound exhibiting a considerable number of positive actions in cell models and living systems. An update, in the form of review, is needed from time to time to get access to the state-of-the-art on this topic. In this review we visited recent and refreshing evidence of new already proven and potential targets to explain the benefits of using SAC against toxic and pathological conditions. The broad spectrum of protective actions covered by this molecule comprises antioxidant, redox modulatory and anti-inflammatory activities, accompanied by anti-apoptotic, pro-energetic and signaling capacities. Herein, we detail the evidence on these aspects to provide the reader a more complete overview on the promising aspects of SAC in research.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Cisteína/análogos & derivados , Alho , Fármacos Neuroprotetores/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Cisteína/química , Cisteína/metabolismo , Cisteína/farmacologia , Humanos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/metabolismo , Oxirredução/efeitos dos fármacos , Receptor para Produtos Finais de Glicação Avançada/metabolismo
18.
Ciênc. rural ; Ciênc. rural (Online);40(12): 2580-2587, dez. 2010. ilus
Artigo em Português | LILACS | ID: lil-570609

RESUMO

O objetivo desta pesquisa foi determinar o teor de compostos funcionais presentes em bulbilhos de alho das cultivares 'Caçador' e 'Peruano', originárias do Brasil, e da cultivar 'Jinxiang', proveniente da China, durante o armazenamento pós-colheita até sessenta dias. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial 3x5 (três cultivares de alho x 5 períodos de armazenagem), com três repetições, sendo a unidade experimental composta por 10 bulbos de alho. Os bulbos foram armazenados à temperatura de 22±1°C e umidade relativa de 70±2 por cento e analisados quinzenalmente para teores de alicina, compostos fenólicos e atividade antioxidante pelo sistema -caroteno/ácido linoléio. De maneira geral, verificou-se que as propriedades funcionais das cultivares de alho estudadas foram alteradas durante o armazenamento. O perfil dos teores de alicina não foi alterado no período de armazenamento para a cultivar 'Caçador'. Entretanto, o perfil foi de degradação do bioativo aos 45 e 15 dias de armazenamento para as cultivares 'Peruano' e 'Jinxiang', respectivamente. O potencial antioxidante, medido pelo sistema -caroteno/ácido linoléico para as cultivares 'Caçador' e 'Jinxiang', foi superior em relação à cultivar 'Peruano', no início da avaliação. O perfil para todas as cultivares foi de redução do potencial, sendo que, a partir dos 30 dias de avaliação, deixou-se de observar essas diferenças. Quanto ao conteúdo de compostos fenólicos totais, observaram-se maiores teores para a cultivar 'Jinxiang' em relação às cultivares 'Caçador' e 'Peruano' no início da avaliação. Todas as cultivares apresentaram aumento significativo a partir dos 15 dias de avaliação. Portanto, as cultivares de alho avaliadas possuem atividade antioxidante, proveniente dos compostos organossulfurados e compostos fenólicos, a qual foi alterada com o armazenamento refrigerado.


The objective of the present research was to determine the content of functional compounds in garlic cloves of two Brazilian cultivars ('Caçador' and 'Peruano') one Chinese cultivar ('Jinxiang'), during the postharvest storage up to 60 days. The experiments were carried out in a completely randomized design, in a factorial scheme 3x5 (3 cultivars; 5 samplings times) with 3 replicates. Experimental unit was comprised by 10 garlic bulbs. Garlic bulbs were stored at 22±1°C and 70±2 percent RH and analyzed, every 15 days for allicin, phenolic compounds and antioxidant activity using the -carotene/linoleic acid method. In general, it was observed that functional compounds were altered in the garlic cultivars studied. The profile of the levels of allicin was not changed during the period of storage for the variety 'Caçador'. However, the profile was of bioactive degradation at 45 and 15 days of storage for 'Peruano' and 'Jinxiang' cultivars, respectively. The antioxidant potential measured by the system ?-carotene/ linoleic acid for cultivars 'Caçador' and 'Jinxiang' were higher than the 'Peruano' cultivar, at the beginning of the evaluation. The profile for all cultivars was of reduction of potential, and after 30 days these differences were no observed. Regarding the content of phenolic compounds it was observed that 'Jinxiang' showed higher levels than in the cultivars 'Peruano' and 'Caçador', at the beginning of the evaluation. All cultivars showed a significant increase from 15 days evaluation. Therefore, the garlic cultivars evaluated had antioxidant activity of compounds derived from organosulfur and phenolic compounds, which was modified with storage under refrigeration.

19.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1478013

RESUMO

The objective of the present research was to determine the content of functional compounds in garlic cloves of two Brazilian cultivars ('Caçador' and 'Peruano') one Chinese cultivar ('Jinxiang'), during the postharvest storage up to 60 days. The experiments were carried out in a completely randomized design, in a factorial scheme 3x5 (3 cultivars; 5 samplings times) with 3 replicates. Experimental unit was comprised by 10 garlic bulbs. Garlic bulbs were stored at 22±1°C and 70±2% RH and analyzed, every 15 days for allicin, phenolic compounds and antioxidant activity using the -carotene/linoleic acid method. In general, it was observed that functional compounds were altered in the garlic cultivars studied. The profile of the levels of allicin was not changed during the period of storage for the variety 'Caçador'. However, the profile was of bioactive degradation at 45 and 15 days of storage for 'Peruano' and 'Jinxiang' cultivars, respectively. The antioxidant potential measured by the system ?-carotene/ linoleic acid for cultivars 'Caçador' and 'Jinxiang' were higher than the 'Peruano' cultivar, at the beginning of the evaluation. The profile for all cultivars was of reduction of potential, and after 30 days these differences were no observed. Regarding the content of phenolic compounds it was observed that 'Jinxiang' showed higher levels than in the cultivars 'Peruano' and 'Caçador', at the beginning of the evaluation. All cultivars showed a significant increase from 15 days evaluation. Therefore, the garlic cultivars evaluated had antioxidant activity of compounds derived from organosulfur and phenolic compounds, which was modified with storage under refrigeration.


O objetivo desta pesquisa foi determinar o teor de compostos funcionais presentes em bulbilhos de alho das cultivares 'Caçador' e 'Peruano', originárias do Brasil, e da cultivar 'Jinxiang', proveniente da China, durante o armazenamento pós-colheita até sessenta dias. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial 3x5 (três cultivares de alho x 5 períodos de armazenagem), com três repetições, sendo a unidade experimental composta por 10 bulbos de alho. Os bulbos foram armazenados à temperatura de 22±1°C e umidade relativa de 70±2% e analisados quinzenalmente para teores de alicina, compostos fenólicos e atividade antioxidante pelo sistema -caroteno/ácido linoléio. De maneira geral, verificou-se que as propriedades funcionais das cultivares de alho estudadas foram alteradas durante o armazenamento. O perfil dos teores de alicina não foi alterado no período de armazenamento para a cultivar 'Caçador'. Entretanto, o perfil foi de degradação do bioativo aos 45 e 15 dias de armazenamento para as cultivares 'Peruano' e 'Jinxiang', respectivamente. O potencial antioxidante, medido pelo sistema -caroteno/ácido linoléico para as cultivares 'Caçador' e 'Jinxiang', foi superior em relação à cultivar 'Peruano', no início da avaliação. O perfil para todas as cultivares foi de redução do potencial, sendo que, a partir dos 30 dias de avaliação, deixou-se de observar essas diferenças. Quanto ao conteúdo de compostos fenólicos totais, observaram-se maiores teores para a cultivar 'Jinxiang' em relação às cultivares 'Caçador' e 'Peruano' no início da avaliação. Todas as cultivares apresentaram aumento significativo a partir dos 15 dias de avaliação. Portanto, as cultivares de alho avaliadas possuem atividade antioxidante, proveniente dos compostos organossulfurados e compostos fenólicos, a qual foi alterada com o armazenamento refrigerado.

20.
Ci. Rural ; 40(12)2010.
Artigo em Português | VETINDEX | ID: vti-706881

RESUMO

The objective of the present research was to determine the content of functional compounds in garlic cloves of two Brazilian cultivars ('Caçador' and 'Peruano') one Chinese cultivar ('Jinxiang'), during the postharvest storage up to 60 days. The experiments were carried out in a completely randomized design, in a factorial scheme 3x5 (3 cultivars; 5 samplings times) with 3 replicates. Experimental unit was comprised by 10 garlic bulbs. Garlic bulbs were stored at 22±1°C and 70±2% RH and analyzed, every 15 days for allicin, phenolic compounds and antioxidant activity using the -carotene/linoleic acid method. In general, it was observed that functional compounds were altered in the garlic cultivars studied. The profile of the levels of allicin was not changed during the period of storage for the variety 'Caçador'. However, the profile was of bioactive degradation at 45 and 15 days of storage for 'Peruano' and 'Jinxiang' cultivars, respectively. The antioxidant potential measured by the system ?-carotene/ linoleic acid for cultivars 'Caçador' and 'Jinxiang' were higher than the 'Peruano' cultivar, at the beginning of the evaluation. The profile for all cultivars was of reduction of potential, and after 30 days these differences were no observed. Regarding the content of phenolic compounds it was observed that 'Jinxiang' showed higher levels than in the cultivars 'Peruano' and 'Caçador', at the beginning of the evaluation. All cultivars showed a significant increase from 15 days evaluation. Therefore, the garlic cultivars evaluated had antioxidant activity of compounds derived from organosulfur and phenolic compounds, which was modified with storage under refrigeration.


O objetivo desta pesquisa foi determinar o teor de compostos funcionais presentes em bulbilhos de alho das cultivares 'Caçador' e 'Peruano', originárias do Brasil, e da cultivar 'Jinxiang', proveniente da China, durante o armazenamento pós-colheita até sessenta dias. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial 3x5 (três cultivares de alho x 5 períodos de armazenagem), com três repetições, sendo a unidade experimental composta por 10 bulbos de alho. Os bulbos foram armazenados à temperatura de 22±1°C e umidade relativa de 70±2% e analisados quinzenalmente para teores de alicina, compostos fenólicos e atividade antioxidante pelo sistema -caroteno/ácido linoléio. De maneira geral, verificou-se que as propriedades funcionais das cultivares de alho estudadas foram alteradas durante o armazenamento. O perfil dos teores de alicina não foi alterado no período de armazenamento para a cultivar 'Caçador'. Entretanto, o perfil foi de degradação do bioativo aos 45 e 15 dias de armazenamento para as cultivares 'Peruano' e 'Jinxiang', respectivamente. O potencial antioxidante, medido pelo sistema -caroteno/ácido linoléico para as cultivares 'Caçador' e 'Jinxiang', foi superior em relação à cultivar 'Peruano', no início da avaliação. O perfil para todas as cultivares foi de redução do potencial, sendo que, a partir dos 30 dias de avaliação, deixou-se de observar essas diferenças. Quanto ao conteúdo de compostos fenólicos totais, observaram-se maiores teores para a cultivar 'Jinxiang' em relação às cultivares 'Caçador' e 'Peruano' no início da avaliação. Todas as cultivares apresentaram aumento significativo a partir dos 15 dias de avaliação. Portanto, as cultivares de alho avaliadas possuem atividade antioxidante, proveniente dos compostos organossulfurados e compostos fenólicos, a qual foi alterada com o armazenamento refrigerado.

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