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1.
Chemosphere ; 240: 124846, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31550594

RESUMO

Cadmium (Cd) precipitation and dissolution in pore water is associated with dissolved organic carbon (DOC)-induced reduction-oxidation of sulfur (S) under waterlogging and is vital for controlling the bioavailability in paddy soil. A 120-day soil incubation experiment, including application of sulfur (S, 30 mg kg-1) and wheat straw (W, 1.0%) alone or in combination (W + S) into Cd-contaminated paddy soil under waterlogging, was conducted to investigate the dynamic of dissolved Cd and its relationship with DOC, S2-, Fe2+, pH, Eh and pe + pH in soil pore water. The results showed that the lowest dissolved Cd concentration was observed in the W + S-treated soil pore water among all treatments when the soil Eh remained at lower values during the period of 15-60 days of incubation, which could be attributed to CdS precipitation and/or co-precipitation of Cd absorbed by FeS2 because of the reduction in sulfur. The application of S resulted in a Cd rebound in the pore water irrespective of W addition when the Eh began to increase from its lowest values during the period of 45-75 days of incubation, and SOB genera were observed in the S added soil. This could be attributed to re-dissolution of the precipitated Cd in soils under the SOB-driven oxidation of sulfide such as CdS and FeS2. In conclusion, DOC-driven reduction-oxidation of sulfur controls Cd dissolution in the pore water of Cd-contaminated paddy soil under waterlogging conditions. Further studies are required to investigate the interaction of sulfur and SOM-induced DOC on Cd bioavailability in rice-planted paddy soils.


Assuntos
Cádmio/uso terapêutico , Poluição Ambiental/efeitos adversos , Poluentes do Solo/química , Enxofre/uso terapêutico , Cádmio/farmacologia , Enxofre/farmacologia , Água
2.
Ecotoxicol Environ Saf ; 184: 109641, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31518827

RESUMO

The objective of this study was to investigate the responses of cadmium (Cd) availability and transfer in the soil-rice system to added sulfur (S) under unstable pe + pH conditions. Different water management conditions (flooding and aerobic treatments) cause changes in the soil pe + pH. We conducted a pot experiment to investigate the influence of S supply on soil Cd availability and Cd accumulation in rice plants (Oryza sativa L.), using three water regimes (continuous dryness, alternating dry-wet for one cycle, and continuous flooding) combined with two S concentrations (0 and 300 mg/kg). The results showed that the flooding treatment was more effective in decreasing soil pe + pH, Cd availability, and Cd accumulation in rice tissues than were the aerobic treatments. S-induced reduction in Cd uptake and translocation in rice was attributed to the decreased soil pe + pH values and enhanced biosynthesis of phytochelatins (PCs) and glutathione (GSH) in rice roots. Microscopic examination showed that the flooding treatment with added soil S resulted in better rice root growth. Element dispersive spectrometer (EDS) analysis indicated that S addition and flooding treatment promoted the formation of iron plaques and increases in Fe concentration in rice tissues. Conversely, partial disintegration of the root epidermis was observed in the dry treatment without added S.


Assuntos
Cádmio/análise , Oryza/metabolismo , Poluentes do Solo/análise , Solo/química , Enxofre/farmacologia , Cádmio/metabolismo , Glutationa/biossíntese , Concentração de Íons de Hidrogênio , Ferro/análise , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Fitoquelatinas/biossíntese , Poluentes do Solo/metabolismo
3.
BMC Genomics ; 20(1): 628, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31370780

RESUMO

BACKGROUND: Free asparagine is the precursor for acrylamide formation during cooking and processing of grains, tubers, beans and other crop products. In wheat grain, free asparagine, free glutamine and total free amino acids accumulate to high levels in response to sulphur deficiency. In this study, RNA-seq data were acquired for the embryo and endosperm of two genotypes of bread wheat, Spark and SR3, growing under conditions of sulphur sufficiency and deficiency, and sampled at 14 and 21 days post anthesis (dpa). The aim was to provide new knowledge and understanding of the genetic control of asparagine accumulation and breakdown in wheat grain. RESULTS: There were clear differences in gene expression patterns between the genotypes. Sulphur responses were greater at 21 dpa than 14 dpa, and more evident in SR3 than Spark. TaASN2 was the most highly expressed asparagine synthetase gene in the grain, with expression in the embryo much higher than in the endosperm, and higher in Spark than SR3 during early development. There was a trend for genes encoding enzymes of nitrogen assimilation to be more highly expressed in Spark than SR3 when sulphur was supplied. TaASN2 expression in the embryo of SR3 increased in response to sulphur deficiency at 21 dpa, although this was not observed in Spark. This increase in TaASN2 expression was accompanied by an increase in glutamine synthetase gene expression and a decrease in asparaginase gene expression. Asparagine synthetase and asparaginase gene expression in the endosperm responded in the opposite way. Genes encoding regulatory protein kinases, SnRK1 and GCN2, both implicated in regulating asparagine synthetase gene expression, also responded to sulphur deficiency. Genes encoding bZIP transcription factors, including Opaque2/bZIP9, SPA/bZIP25 and BLZ1/OHP1/bZIP63, all of which contain SnRK1 target sites, were also expressed. Homeologues of many genes showed differential expression patterns and responses, including TaASN2. CONCLUSIONS: Data on the genetic control of free asparagine accumulation in wheat grain and its response to sulphur supply showed grain asparagine levels to be determined in the embryo, and identified genes encoding signalling and metabolic proteins involved in asparagine metabolism that respond to sulphur availability.


Assuntos
Asparagina/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genótipo , Enxofre/farmacologia , Triticum/genética , Triticum/metabolismo , Análise de Sequência de RNA , Fatores de Transcrição/genética , Triticum/efeitos dos fármacos , Triticum/enzimologia
4.
Eur J Med Chem ; 180: 486-508, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31330449

RESUMO

From many decades, S-heterocycles have maintained their status as an important part and core of FDA approved drugs and medicinally active compounds. With exhaustive exploration of nitrogen heterocycles in medicinal chemistry, researchers have shifted their interest towards other heterocycles, especially, S-heterocycles. Thus several attempts have been made to synthesize a variety of new sulphur containing compounds with high medicinal value and low toxicity profile, in comparison to previous N-heterocycles. Till today, S-heterocycle containing compounds have been largely reported as anticancer, antidiabetic, antimicrobial, antihypertension, antivral, antinflammatory etc. In this review, the authors have tried to provide a critical analysis of synthesis and medicinal attributes of sulphur containing heterocycles such as thiirane, thiophene, thiazole, thiopyran, thiazolidine etc reported within last five years to emphasize the significance and usefulness of these S-heterocycles in the drug discovery process.


Assuntos
Compostos Heterocíclicos/farmacologia , Enxofre/farmacologia , Animais , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Hipertensivos/síntese química , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Química Farmacêutica , Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/química , Humanos , Hipoglicemiantes/síntese química , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Enxofre/química
5.
Chemosphere ; 234: 346-355, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31228836

RESUMO

Land application of sewage sludge has received significant attention in recent years but the presence of elevated heavy metals in the sludge limits its land application. The purposes of this study were to investigate the effects of sulfur dosage and inoculum size on the thermophilic bioleaching of heavy metals from sewage sludge in a pilot-scale bioreactor. The microbial communities in this thermophilic bioleaching process were also identified using real-time polymerase chain reaction (real-time PCR). The results showed that the oxidation of sulfur and metal solubilization decreased with the increasing sulfur dosage. When the sulfur dosage was greater than 2% (w/v), the sulfur oxidation and metal solubilization rates decreased, indicating that the thermophilic bioleaching was hindered by high levels of substrate. However, it was found that the efficiency of metal solubilization and solid degradation was increased with the increase of inoculum size in the range from 5% to 20%. At the end of bioleaching, the efficiency of Mn, Zn, Ni, Cu and Cr from the sewage sludge reached 73-100%, 51-60%, 38-52%, 17-43% and 1-38%, respectively, while SS and VSS were degraded by 33-48% and 47-67%, respectively. Based on the analysis of real-time PCR, Sulfobacillus acidophilus was observed to be the predominant species (13-67% of total bacteria), whereas the populations of Sulfobacillus thermosulfidooxidans and Acidithiobacillus caldus were accounted relatively low (<1%).


Assuntos
Inoculantes Agrícolas , Metais Pesados/isolamento & purificação , Esgotos/química , Enxofre/farmacologia , Acidithiobacillus/metabolismo , Bactérias/metabolismo , Reatores Biológicos , Concentração de Íons de Hidrogênio , Metais Pesados/análise , Oxirredução , Projetos Piloto , Esgotos/microbiologia , Enxofre/análise , Eliminação de Resíduos Líquidos/métodos
6.
Ecotoxicol Environ Saf ; 180: 656-667, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31136876

RESUMO

Owing to the active use of rare-earth elements in many areas, it is necessary to study their behavior in the environment and their biological impact on plants. Despite the role of melatonin and sulfur in plant growth, development and abiotic stress tolerance; it is still not clear how they have a strong regulatory influence and synergistic effect on growth, physiological and biochemical characteristics of plants under different environmental stresses. Therefore, this study highlights how melatonin and sulfur together potentially involved in a reversal of lanthanum-inhibited photosynthetic and growth responses in tomato seedlings. Here, we reported that seedlings grown in a medium containing 150 µM lanthanum exhibited increased overproduction of reactive oxygen species (ROS) and lipid peroxidation together with increased Chlorophyll degradation, and activity of chlorophyllase, proline dehydrogenase and glycolate oxidase (GOx), and decreased photosynthesis and growth. However, the application of melatonin and sulfur showed significant responses on tomato seedlings, although the response of their combined treatment was more effective by further increasing photosynthesis and growth under lanthanum toxicity. Melatonin supplied with sulfur suppressed ROS formation, lipid peroxidation and activity of GOx, and increased photosynthesis by upregulating activities of carbonic anhydrase and ribulose-1,5-bisphosphate carboxylase/oxygenase. Also, sulfur supplementation with melatonin to seedlings resulted in an elevation in the accumulation of Chl and proline by increasing δ-aminolevulinic acid and activity of δ-aminolevulinic acid dehydratase and Δ1-pyrroline-5-carboxylate synthetase activity. The administration of melatonin with sulfur substantially induced upregulation of enzymes (superoxide dismutase, ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase and glutathione reductase) activities involved in the antioxidant system, thereby mitigating ROS-induced oxidative damage. Thus, this study provides strong evidence that melatonin and sulfur have strong regulatory influence and synergistic role in alleviating the adverse effect of lanthanum-toxicity by increasing photosynthesis and growth.


Assuntos
Poluentes Ambientais/toxicidade , Lantânio/toxicidade , Lycopersicon esculentum/efeitos dos fármacos , Melatonina/farmacologia , Enxofre/farmacologia , Antioxidantes/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Fotossíntese/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-30912480

RESUMO

Urinary tract infections (UTIs) have been frequently reported from different parts of the world. The current knowledge on distribution of causative agents of urinary infections and antibiotics susceptibility pattern is essentially required. In the present study, total 351 uropathogenic bacteria were isolated; among them most prevalent were Escherichia coli (75%), followed by Pseudomonas aeruginosa (8%), Proteus mirabilis (6%), Klebsiella pneumoniae (4%), Staphylococcus aureus (4%) and Enterococcus faecalis (3%). Most isolates of uropathogenic bacteria showed resistance to amoxicillin and trimethoprim, followed by chloramphenicol and kanamycin. Biosynthesis of sulfur nanoparticles (SNPs) was performed by co-precipitation method using sodium thiosulfate in presence of Catharanthus roseus leaf extract. The characterization data showed that SNPs were polydispersed, spherical in shape with size range of 20-86 nm and having negative zeta potential of -9.24 mV. The potential antibacterial activity was observed for SNPs alone and in combination with antibiotics particularly amoxicillin and trimethoprim against majority of the uropathogens. The synergistic effect yielded increase in fold area with high activity index against tested uropathogens. Based on overall results, it can be recommended to use SNPs for the management of UTI alone and also in combination with antibiotics.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Nanopartículas/química , Enxofre/farmacologia , Infecções Urinárias/microbiologia , Antibacterianos/química , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Proteus mirabilis/efeitos dos fármacos , Proteus mirabilis/isolamento & purificação , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Enxofre/química
8.
Gut Microbes ; 10(4): 447-457, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30810441

RESUMO

High-protein diets may be linked to gut inflammation due to increased production of hydrogen sulfide (H2S), a potential toxin, as an end product of microbial fermentation in the colon by sulfidogenic sulfate-reducing bacteria (SRB). We hypothesized that dietary content of sulfur-containing amino acids (SAA) leads to variation in the relative abundances of intestinal SRB, which include Desulfovibrio and Bilophila taxa. To test this hypothesis we performed a pilot crossover study in four healthy volunteers, who consumed two interventional diets for 10-14 days, containing high or low SAA content. The total energy intake was similar between the two dietary extremes. Microbial communities were characterized by 16S rRNA gene amplicon and shotgun next-generation DNA sequencing. While the relative abundance of Desulfovibrio differed among participants (ANOVA P= 0.001), we could not detect a change with dietary treatments. Similarly, no differences in Bilophila abundance were observed among individuals or dietary arms. Inter-personal differences in microbial community composition and functional gene categories differed between subjects and these differences were maintained over the course of the study. These observations are consistent with re-analysis of two previously published dietary intervention studies. Finally, we found that inter-personal differences in the taxonomic composition of fecal microbiota, including the relative abundances of SRB, were maintained over time in 19 healthy individuals in our stool donor program. These results suggest that the use of dietary interventions alone may be insufficient for rapid therapeutic targeting of SRB. Nevertheless, these pilot data provide a foundation to inform future, statistically powered, studies.


Assuntos
Bactérias/efeitos dos fármacos , Dieta , Intestinos/microbiologia , Sulfatos/metabolismo , Enxofre/metabolismo , Adulto , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Bilophila/genética , Bilophila/crescimento & desenvolvimento , Bilophila/metabolismo , Estudos Cross-Over , Desulfovibrio/genética , Desulfovibrio/crescimento & desenvolvimento , Desulfovibrio/metabolismo , Fezes/microbiologia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética , Enxofre/farmacologia
9.
Comput Biol Chem ; 79: 73-82, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30731361

RESUMO

Computational quantum chemical study and biological evaluation of a synthesized novel sulfur heterocyclic thiophene derivative containing 1,2,3-triazole and pyridine moieties namely BTPT [2-(1-benzyl-5-methyl-1H-1,2,3-triazol-4-yl)-6-methoxy-4-(thiophen-2-yl) pyridine] was presented in this study. The crystal structure was determined by SCXRD method. For the title compound BTPT, spectroscopic characterization like 1H NMR, 13C NMR, FTIR, UV-vis were carried out theoretically by computational DFT method and compared with experimental data. Druglikeness parameters of BTPT were found through in silico pharmacological ADMET properties estimation. The molecular docking investigation was performed with human topoisomerase IIα (PDB ID:1ZXM) targeting ATP binding site. In vitro cytotoxicity activity of BTPT/doxorubicin were examined by MTT assay procedure against three human cancer cell lines A549, PC-3, MDAMB-231 with IC50 values of 0.68/0.70, 1.03/0.77 and 0.88/0.98 µM, respectively. Our title compound BTPT reveals notable cytotoxicity against breast cancer cell (MDAMB-231), moderate activity with human lung cancer cell (A-549) and less inhibition with human prostate cancer cell (PC-3) compared to familiar cancer medicine doxorubicin. From the results, BTPT could be observed as a potential candidate for novel anticancer drug development process.


Assuntos
Antineoplásicos/farmacologia , Teoria da Densidade Funcional , Simulação de Acoplamento Molecular , Proteínas de Ligação a Poli-ADP-Ribose/antagonistas & inibidores , Inibidores da Topoisomerase II/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA Topoisomerases Tipo II/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Humanos , Estrutura Molecular , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Piridinas/química , Piridinas/farmacologia , Relação Estrutura-Atividade , Enxofre/química , Enxofre/farmacologia , Tiofenos/química , Tiofenos/farmacologia , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/química , Triazóis/química , Triazóis/farmacologia
10.
Dalton Trans ; 48(4): 1292-1313, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30608086

RESUMO

Rational ligand design approaches allowed {Cu2(µ-OH/OMe)} cores to be accommodated within µ-phenoxido bis(tetradentate) and µ-phenoxido bis(tridentate) ligands having thioether donors. The complexes [Cu2(µ-H2L1)(µ-OH)](ClO4)2·2H2O (1), [Cu2(µ-L2)(µ-OH)(OH2)](ClO4)2 (2a) and [Cu2(µ-L2)(µ-OCH3)(OH2)](ClO4)2 (2b) were obtained from an N2O3S2 donor set bearing the H3L1 ligand (2,6-bis-[{2-(2-hydroxyethylthio)ethylimino}methyl]-4-methylphenol) and N2OS2 donor set containing the HL2 ligand (4-methyl-2,6-bis-[{2-(methylthio)phenylimino}methyl]phenol) without showing double phenoxido bridging or any type of preformed inter-fragment aggregation. Previously, we showed that H3L (2,6-bis[((2-(2-hydroxyethoxy)ethyl)imino)methyl]-4-methylphenol), the ether analogue of H3L1, in the presence of carboxylate anions, was responsible for the self-aggregation of preformed {Cu2} fragments and gave two types of [Cu4] complexes comprising [Cu4O] and [Cu4(OH)2] cores (T. S. Mahapatra, A. Bauzá, D. Dutta, S. Mishra, A. Frontera and D. Ray, ChemistrySelect, 2016, 1, 64-74). The molecular structures of 1, 2a and 2b were determined via single crystal X-ray diffraction and solution studies, which indicated the presence of [Cu2] species. This was further confirmed via UV-vis spectroscopy and HRMS analysis. The synthesized complexes were screened for their potential as catalysts for the catalytic oxidation of 3,5-di-tert-butylcatechol (3,5-DTBCH2). A change in the mechanism of catalytic oxidation was observed with a change in the ligand backbone. All three complexes also showed DNA binding properties, which were further substantiated via molecular docking studies. Their DNA binding affinities were quantitatively ascertained using their intrinsic binding constant, Kb, values which were found to be 4.2 × 104, 5.6 × 104 and 4.8 × 104 M-1, respectively. Furthermore, the complexes displayed efficient DNA cleavage behaviour with pBR322 and the oxidative path was established in presence of ROS, singlet oxygen, 1O2, and the superoxide anion, O2·-.


Assuntos
Catecol Oxidase/metabolismo , Complexos de Coordenação/farmacologia , Clivagem do DNA/efeitos dos fármacos , DNA/metabolismo , Catecóis/metabolismo , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Cobre/química , Cobre/farmacologia , DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Éteres/química , Éteres/farmacologia , Peróxido de Hidrogênio/análise , Concentração de Íons de Hidrogênio , Cinética , Ligantes , Simulação de Acoplamento Molecular , Estrutura Molecular , Oxirredução , Relação Estrutura-Atividade , Compostos de Sulfidrila/química , Compostos de Sulfidrila/farmacologia , Enxofre/química , Enxofre/farmacologia
11.
Biochem Biophys Res Commun ; 508(2): 550-555, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30509490

RESUMO

We previously reported that Ca2+/calmodulin-dependent protein kinase II (CaMKII) is inhibited by S-nitrosylation of Cys6 in cells. Herein, we show that polysulfidation of CaMKII at Cys6 limits its enzyme activity following reactive sulfur species (RSS) stimulus. In vitro incubation of CaMKII with the RSS donor, Na2S4, induced the inhibition of the enzyme via its polysulfidation. Treatment with dithiothreitol reversed the polysulfidation and the subsequent inhibition. The inhibition of CaMKII by Na2S4 is competitive with ATP but not with the peptide substrate Syntide-2. In transfected cells expressing CaMKII, the enzyme activity decreased upon treatment with Na2S4, whereas cells expressing mutant CaMKII (C6A) were resistant to this treatment. In addition, the endogenous CaMKII was inhibited by treatment with Na2S4 in RAW264.7 murine macrophage cells. These results suggest a novel regulation of CaMKII by RSS via its Cys6 polysulfidation in cells.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Enxofre/farmacologia , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Cisteína/metabolismo , Ditiotreitol/farmacologia , Ativação Enzimática/efeitos dos fármacos , Camundongos , Oxirredução , Células RAW 264.7 , Sulfetos
12.
Microb Drug Resist ; 25(4): 594-602, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30461338

RESUMO

Over the last decade, nanotechnology-based therapeutic platforms have been directed toward developing nanoparticles with unique properties to combat biofilms. In this study, we evaluated the antibiofilm activity of the sulfur-functionalized fullerene nanoparticles (SFF Nps) against Pseudomonas aeruginosa and also analyzed the effect of this nanoparticle on the expression of exotoxin A (toxA) gene. The functionalized fullerenes were prepared by chemical vapor deposition method. We assessed the potential of SFF Nps to inhibit biofilm formation and eradicate preformed biofilms. Also, the effect of this nanoparticle on the expression of toxA gene was investigated by real-time PCR. The minimum biofilm inhibitory concentration of SFF Nps was 1 mg/mL. The minimum biofilm-eradication concentration of SFF Nps on the young (24- and 48-hr old) and older (72- and 96-hr old) biofilms was 2 and 4 mg/mL, respectively. Field emission electron scanning microscopy images confirmed the potent ability of SFF Nps to eradicate biofilm of P. aeruginosa. The expression of toxA was downregulated in the presence of SFF Nps. In conclusion, considering the ability of SFF Nps to kill P. aeruginosa biofilm and downregulate the expression of exotoxin A, this nanoparticle can be used for treatment of both chronic and acute P. aeruginosa infections.


Assuntos
ADP Ribose Transferases/genética , Antibacterianos/farmacologia , Toxinas Bacterianas/genética , Biofilmes/efeitos dos fármacos , Exotoxinas/genética , Fulerenos/farmacologia , Nanopartículas/química , Pseudomonas aeruginosa/efeitos dos fármacos , Enxofre/farmacologia , Fatores de Virulência/genética , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Testes de Sensibilidade Microbiana/métodos , Pseudomonas aeruginosa/genética
13.
Appl Biochem Biotechnol ; 187(3): 724-743, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30043149

RESUMO

Interests in biosurfactant in industrial and environmental applications have increased considerably in recent years, owing to their potential benefits over synthetic counterparts. The present study aimed at analyzing the stability and oil removal efficiency of a new lipopeptide biosurfactant produced by Paenibacillus sp. D9 and its feasibility of its use in biotechnological applications. Paenibacillus sp. D9 was evaluated for optimal growth conditions and improved production yield of lipopeptide biosurfactant with variations in different substrate parameters such as carbon (C), nitrogen (N), C:N: ratio, metal supplements, pH, and temperature. Enhanced biosurfactant production was observed when using diesel fuel and ammonium sulfate as carbon and nitrogen source respectively. The maximum biosurfactant yield of 4.11 g/L by Paenibacillus sp. D9 occurred at a C/N ratio of 3:1, at pH 7.0, 30 °C, 4.0 mM MgSO4, and 1.5% inoculum size. The D9 biosurfactant was found to retain surface-active properties under the extreme conditions such as high thermal, acidic, alkaline, and salt concentration. The ability to emulsify further emphasizes its potential usage in biotechnological application. Additionally, the lipopeptide biosurfactant exhibited good performance in the degradation of highly toxic substances when compared with chemical surfactant, which proposes its probable application in biodegradation, microbial-enhanced oil recovery or bioremediation. Furthermore, the biosurfactants were effective in a test to stimulate the solubilization of hydrophobic pollutants in both liquid environments removing 49.1 to 65.1% diesel fuel including hydrophobic pollutants. The study highlights the usefulness of optimization of culture parameters and their effects on biosurfactant production, high stability, improved desorption, and solubilization of hydrophobic pollutants.


Assuntos
Biotecnologia/métodos , Poluentes Ambientais/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Lipopeptídeos/metabolismo , Paenibacillus/efeitos dos fármacos , Paenibacillus/metabolismo , Tensoativos/metabolismo , Biodegradação Ambiental , Biomassa , Carbono/farmacologia , Poluentes Ambientais/química , Poluentes Ambientais/isolamento & purificação , Gasolina , Concentração de Íons de Hidrogênio , Nitrogênio/farmacologia , Estabilidade Proteica , Enxofre/farmacologia , Temperatura Ambiente
14.
Eur J Nutr ; 58(5): 1847-1851, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29808273

RESUMO

PURPOSE: The objective of this study was to evaluate the capacity of modified phenols synthesized from hydroxytyrosol, a natural olive oil phenol, specifically those containing a selenium or sulphur group, to inhibit lipid peroxidation. METHODS: The compounds' abilities to inhibit lipid peroxidation in liver microsomes obtained from vitamin E-deficient rats were compared to hydroxytyrosol. RESULTS: All synthetic compounds had a significant higher ability to inhibit lipid peroxidation than hydroxytyrosol. Selenium derivates displayed a higher antioxidant activity than sulphur derivatives. In addition, the antioxidant activity increased with a higher number of heteroatoms in the hydroxytyrosol molecular structure. CONCLUSION: The study shows, for the first time, the ability of synthetic compounds, derived from the most active phenol present in olives in free form (hydroxytyrosol), and containing one or two atoms of sulphur or selenium, to inhibit the lipid peroxidation of vitamin E-deficient microsomes. The antioxidant activity of five thioureas, a disulfide, a thiol, three selenoureas, a diselenide, and a selenonium were evaluated and the results showed a higher inhibition of lipid peroxidation than the natural phenol. Selenium and sulphur derivatives of hydroxytyrosol are novel antioxidants with the potential to supplement the lack of vitamin E in the diet as natural alternatives for the prevention of diseases related to oxidative damage.


Assuntos
Peroxidação de Lipídeos/efeitos dos fármacos , Microssomos Hepáticos/efeitos dos fármacos , Álcool Feniletílico/análogos & derivados , Selênio/farmacologia , Enxofre/farmacologia , Deficiência de Vitamina E , Animais , Modelos Animais de Doenças , Álcool Feniletílico/farmacologia , Ratos
15.
Mar Drugs ; 16(10)2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30314382

RESUMO

Arsenicin A (C3H6As4O3) was isolated from the New Caledonian poecilosclerid sponge Echinochalina bargibanti, and described as the first natural organic polyarsenic compound. Further bioguided fractionation of the extracts of this sponge led us to isolate the first sulfur-containing organic polyarsenicals ever found in Nature. These metabolites, called arsenicin B and arsenicin C, are built on a noradamantane-type framework that is characterized by an unusual As⁻As bonding. Extensive NMR measurements, in combination with mass spectra, enabled the assignment of the structure for arsenicin B (C3H6As4S2) as 2. The scarcity of arsenicin C and its intrinsic chemical instability only allowed the collection of partial spectral data, which prevented the full structural definition. After the extensive computational testing of several putative structures, structure 3 was inferred for arsenicin C (C3H6As4OS) by comparing the experimental and density functional theory (DFT)-calculated ¹H and 13C NMR spectra. Finally, the absolute configurations of 2 and 3 were determined with a combined use of experimental and time-dependent (TD)-DFT calculated electronic circular dichroism (ECD) spectra and observed specific rotations. These findings pose great challenges for the investigation of the biosynthesis of these metabolites and the cycle of arsenic in Nature. Arsenicins B and C showed strong antimicrobial activities, especially against S. aureus, which is comparable to the reference compound gentamycin.


Assuntos
Arsenicais/farmacologia , Poríferos/química , Enxofre/farmacologia , Animais , Anti-Infecciosos/farmacologia , Dicroísmo Circular/métodos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Staphylococcus aureus/efeitos dos fármacos
16.
Mar Pollut Bull ; 135: 1174-1182, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30301016

RESUMO

Sulfur and iron are abundant and have close, complex interactions with the biogeochemical cycle of arsenic (As) in mangrove ecosystems. A hydroponic experiment was conducted to investigate the influences of variable SO42- and Fe2+ supplies on radial oxygen loss (ROL), iron plaque formation and As translocation in Avicennia marina upon exposure to As(III). The results indicate that A. marina is an As-tolerant plant, the application of iron and sulfur not only showed positive growth effects but also induced much higher amounts of ROL-induced iron plaque formation on root surfaces. The presence of iron plaque remarkably improved the proportion of As sequestration near this area but consequently reduced the proportion of As translocation in root. Therefore, it is concluded that iron plaque may act as a barrier for protection against As, and iron and sulfur play important roles in controlling the growth and translocation of As in A. marina seedlings.


Assuntos
Arsênico/farmacocinética , Avicennia/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Poluentes Químicos da Água/farmacocinética , Arsênico/toxicidade , Avicennia/metabolismo , Ecossistema , Hidroponia , Ferro/farmacologia , Oxigênio/metabolismo , Raízes de Plantas/metabolismo , Plântula/efeitos dos fármacos , Plântula/metabolismo , Enxofre/farmacologia , Poluentes Químicos da Água/toxicidade
17.
Mater Sci Eng C Mater Biol Appl ; 92: 508-517, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30184776

RESUMO

Sulfur nanoparticles (SNPs) were prepared using sodium thiosulfate and hydrochloric acid, and the UV-visible spectrum showed the formation of nanoparticulate sulfur. The SNPs were characterized by UV-visible spectrophotometer, transmission electron microscope (TEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The antibacterial activity and the cytotoxic effects of the SNPs on the human lung carcinoma (A549), mouse colon carcinoma (CT26), Caco-2, and human fibroblast (CCD-986sk) cells were tested. In addition, the inhibitory effect of the SNPs on the cancer cell migration was evaluated. The SNPs capped with chitosan (SNP2) exhibited strong antibacterial activity against Escherichia coli and Staphylococcus aureus. SNP2 also effectively inhibited the proliferation and migration of cancer cells with minimal toxic effect on normal cells. SNP2 therefore has potential for medical applications, including those used as antibacterial and chemotherapeutic agents.


Assuntos
Antibacterianos , Citotoxinas , Escherichia coli/crescimento & desenvolvimento , Staphylococcus aureus/crescimento & desenvolvimento , Enxofre , Células A549 , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Células CACO-2 , Quitosana/química , Quitosana/farmacologia , Citotoxinas/síntese química , Citotoxinas/química , Citotoxinas/farmacologia , Humanos , Enxofre/química , Enxofre/farmacologia
18.
Eur J Med Chem ; 158: 720-732, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30245396

RESUMO

Five series of chromans with urea and thiourea linkers connecting a chroman unit (ring A) and a 4-substituted benzene unit (ring B) have been prepared and evaluated relative to SHetA2 (NSC 721689) for activity against the human A2780 ovarian cancer cell line. The lead compound SHetA2 had a sulfur in place of the oxygen in ring A and a thiourea linker to ring B. The 2-Me-4-Me series (two sets of geminal dimethyl groups at C2 and at C4 on the ring A unit) permitted direct comparison with SHetA2. Ring B in this series was evaluated with specific functional groups at C4 on the ring, including NO2, CO2Et, CF3, OCF3, CN and SO2NH2. The 2-H-4-Me series (only one geminal dimethyl group at the C4 position on ring A) permitted structure-activity relationship analysis to assess the importance of the hydrophobic geminal dimethyl groups on ring A to the activity of SHetA2. The remaining three series 2-Et-4-Me, 2-Me-4-Et and 2-Et-4-Et (ring A methyl groups replaced with ethyls at C2, at C4 and at both C2 and C4, respectively) offered the opportunity to modulate the hydrophobicity of the chroman moiety. Additionally, in all these series, the influence of a urea versus a thiourea linker was also investigated. The results of these modifications are summarized below. The exact analog of SHetA2 with oxygen substituted for sulfur in ring A (2a) showed comparable efficacy but a significantly lower IC50 against the ovarian cancer cell line. The urea linked analogs bearing CN, CF3 and OCF3 at C4 of ring B (3c,d and f) showed greater efficacy than SHetA2, but also had lower IC50 values. Removing the geminal dimethyl group at C2 (4a-c, 5a-c) caused a significant lowering of the efficacy and percent growth inhibition, indicating that the hydrophobic geminal dimethyl group at C2 in ring A is crucial for activity. Finally, replacing the geminal dimethyl groups with geminal diethyls on ring A in the urea derivatives gave 6b-c, 7c-d and 8b, all of which outperformed SHetA2 with respect to efficacy and IC50. The results for compounds 4-8 are in concurrence with modeling studies, which predicted that greater hydrophobicity in ring A would be beneficial. Binding energies were determined for compounds docked in silico to mortalin, the protein identified as a receptor of SHetA2. The urea linker promoted activity comparable to or, in some cases, greater than compounds with a thiourea linker. Several compounds achieved 94% efficacy and an IC50 of 2 µM, which were better than SHetA2 (84%, 3 µM).


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Cromanos/química , Cromanos/farmacologia , Tionas/química , Tionas/farmacologia , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Cromanos/síntese química , Feminino , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Simulação de Acoplamento Molecular , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Oxigênio/química , Oxigênio/farmacologia , Enxofre/química , Enxofre/farmacologia , Tionas/síntese química , Tioureia/análogos & derivados , Tioureia/síntese química , Tioureia/farmacologia , Ureia/análogos & derivados , Ureia/síntese química , Ureia/farmacologia
19.
PLoS One ; 13(9): e0204376, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30235325

RESUMO

Because sulfur (S) depletion in soil results in seed yield losses and grain quality degradation, especially in high S-demanding crops such as oilseed rape (Brassica napus L.), monitoring S fertilisation has become a central issue. Crop models can be efficient tools to conduct virtual experiments under different fertilisation management strategies. Using the process-based model SuMoToRI, we aimed to analyse the impact of different S fertilisation strategies coupled with the variablility observed in major plant characteristics in oilseed rape i.e. radiation use efficiency (RUE), carbon (C) allocation to the leaves (ß) and specific leaf area (SLA) on plant performance-driven variables encompassing total biomass (TDW), S in the photosynthetic leaves (QSmobile.GL) and leaf area index (LAIGL). The contrasting S supply conditions differed in the amount of S (5 levels), and the timing of application (at bolting and/or at flowering, which included a fractioned condition). For this purpose, we performed a global sensitivity analysis (GSA) and calculated two sensitivity indices i.e. the Partial Raw Correlation Coefficient (PRCC) and the Sobol index. The results showed that whatever the timing of S supply, TDW, LAIGL and QSmobile.GL increased as S input increased. For a given S supply, there was no difference in TDW, LAIGL and QSmobile.GL between a single and a fractioned supply. Moreover, delaying the supply until flowering reduced the TDW and LAIGL whereas QSmobile.GL increased. Results showed that RUE had the greatest impact on TDW under all levels of S supply and all application timings, followed by ß and SLA. RUE mostly impacted on QSmobile.GL, depending on S supply conditions, whereas it was the parameter with the least impact on LAIGL. Ultimately, our results provide strong evidence of optimised S fertilisation timings and plant characteristics that will guide producers in their agricultural practices by using specific varieties under constrained S fertilisation strategies.


Assuntos
Brassica napus/efeitos dos fármacos , Enxofre/farmacologia , Biomassa , Brassica napus/crescimento & desenvolvimento , Brassica napus/metabolismo , Fertilizantes , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Estações do Ano , Solo/química
20.
Anticancer Res ; 38(8): 4577-4584, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30061224

RESUMO

BACKGROUND/AIM: Multidrug resistance leads to therapeutic difficulties. There is great interest in experimental chemotherapy regarding multidrug resistance inhibitors and new anticancer agents. The aim of this study was to evaluate the anticancer activity of exocyclic sulfur and selenoorganic compounds on mouse T-lymphoma cell lines. MATERIALS AND METHODS: A series of eighteen sulfur and selenium analogues of 2[1H]-pyrimidinone and hydantoin derivatives were evaluated towards their efflux modulating, cytotoxic and antiproliferative effects in mouse T-lymphoma cells. The combination assay with doxorubicin on multidrug resistant mouse T-lymphoma cells was performed in order to see the nature of drug interactions. Crystal structures were determined for two selected compounds with the highest efflux-modulating activity. RESULTS: The sulfur analogues with aromatic rings almost perpendicular to pyrimidinethione ring at positions 1 and 6 showed the highest efflux inhibitory action, while all selenium analogues showed good antiproliferative and cytotoxic activities. CONCLUSION: The sulfur analogues can be modified towards improving their efflux inhibitory activity, whereas the selenium towards antiproliferative and cytotoxic activities.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Linfoma de Células T/tratamento farmacológico , Selênio/química , Selênio/farmacologia , Enxofre/química , Enxofre/farmacologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citotoxinas/química , Citotoxinas/farmacologia , Doxorrubicina/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Camundongos
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