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1.
Ecotoxicol Environ Saf ; 183: 109567, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31442802

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are universal organic pollutants in the agro ecosystems in China, therefore, it is important to understand the uptake and accumulation of PAHs in crops growing on PAHs contaminated soils for human health risk assessments. Water management is a common practice to maintain high grain yields during wheat production. However, the effects of soil water content on the accumulation and translocation of PAHs in wheat are still not clear. The main objectives of the present study were to investigate the effects of soil water content on the accumulation of three selected PAHs (Σ3PAHs, phenanthrene, anthracene and pyrene) in wheat during whole plant growth stage and on translocation or remobilization of Σ3PAHs from vegetative tissues to wheat grains. Winter wheat (Triticum aestivum cv. Xiaoyan22) were grown on Σ3PAHs spiked soils maintaining 80%, 60% or 40% water-holding capacity during the whole plant growth stage. Plant samplings were performed at jointing, anthesis or maturity stage, respectively. The present study showed that grain yield and biomass of the crop increased with soil water content increasing. Transpiration rate of wheat leaf under 80% and 60% water-holding capacity treatments was significantly (p < 0.05) higher than that under 40% water-holding capacity treatment at both anthesis and filling stage. Soil water content and plant growth stage had significant (p < 0.0001) effects on concentrations of phenanthrene, anthracene and pyrene in winter wheat. When exposed to 0, 15, 60, and 150 mg kg-1 Σ3PAHs in soils, Σ3PAHs concentrations in the grains under 60% water-holding capacity treatment were 46.6%, 69.9%, 89.5% and 81.7% of those under 80% water-holding capacity treatment, respectively. The highest concentrations of Σ3PAHs in the crop were recorded at anthesis stage. The distribution of PAHs in different tissues of wheat varied among different soil water treatments and plant growth stages. The present study indicated that optimizing soil water content during winter wheat production could apparently reduce concentrations of Σ3PAHs in grains via influence root uptake of Σ3PAHs and translocation of Σ3PAHs from stem or leaf into grain, suggesting the potential of water management to cope with PAHs contamination in crops growing on PAHs contaminated soils.


Assuntos
Antracenos/análise , Fenantrenos/análise , Pirenos/análise , Solo/química , Triticum/química , Água/análise , Antracenos/metabolismo , Transporte Biológico , Biomassa , China , Grão Comestível/química , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Fenantrenos/metabolismo , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Pirenos/metabolismo , Estações do Ano , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Água/metabolismo
2.
Food Chem ; 297: 124977, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253260

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are primarily produced during the incomplete combustion of organic matter. PAHs are suspected endocrine disruptors and possible carcinogenic materials. The major sources of human exposure to PAHs are inhaled fumes and food. The aim of this study was to provide an alternative drying method to mitigate PAH formation in dried red peppers. We prepared dried red pepper samples using air-drying and heat pump-assisted drying methods, and measured the concentrations of four PAHs (PAH4), benzo[a] anthracene (B[a]A), chrysene (CHR), benzo[b]fluoranthene (B[b]F), and benzo[a]pyrene (B[a]P), in the resulting pepper samples. The PAH concentrations ranged from 3.61 to 18.0 µg/kg and from 2.22 to 8.35 µg/kg in the air-dried and heat pump-dried pepper samples, respectively. Overall, the results have shown that dried peppers contain PAH4, that the drying conditions for these contaminants should be optimized for mitigating the PAH formation in dried red peppers.


Assuntos
Capsicum/química , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Antracenos/análise , Antracenos/metabolismo , Benzo(a)pireno/análise , Benzo(a)pireno/metabolismo , Carcinógenos/análise , Carcinógenos/metabolismo , Crisenos/análise , Crisenos/metabolismo , Dessecação , Fluorenos/análise , Fluorenos/metabolismo , Temperatura Alta , Hidrocarbonetos Policíclicos Aromáticos/análise
3.
Colloids Surf B Biointerfaces ; 179: 180-189, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30959230

RESUMO

Fluorophores are used for sensing biologically relevant ions, toxic metals or pathogenic markers. However, the mode of entry of such fluorophores into the cell greatly depends on their size, shape, surface charge, functional groups, and hydrophobicity. In particular, the influence of hydrophobicity on the intracellular uptake of fluorophores is poorly investigated. Self-assembly is a recent strategy to tune the intracellular uptake of fluorophores, facilitating increased intracellular sensing and fluorescence. Herein, self-assembly of three novel poly(aryl ether) dendron derivatives that contain rhodamine units was used to investigate the effect of hydrophobicity on the intracellular uptake of self-assembled fluorophores. The results suggest that monomer hydrophobicity plays an important role in the uptake. The dendron-based fluorophores, which upon self-assembly, formed stable spherical aggregates ranging from 300 to 500 nm. The rhodamine-based dendrons could selectively sense Hg2+ ions in the presence of other competing metal cations. Intracellular imaging of the dendron-based fluorophores displayed bright red fluorescence in human embryonic kidney cells. The rate of intracellular uptake of the three dendron-based fluorophores was analyzed by flow cytometry. The results establish the importance of the hydrophilic-lipophilic balance of the self-assembled amphiphiles for tuning the intracellular uptake.


Assuntos
Antracenos/metabolismo , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Espaço Intracelular/metabolismo , Metais/análise , Sobrevivência Celular , Endocitose , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Células HEK293 , Humanos , Íons , Mercúrio/análise , Espectrometria de Fluorescência
4.
Analyst ; 144(8): 2696-2703, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30860221

RESUMO

A urea derivative L1 exhibits Aggregation-Induced Emission (AIE) activity in an acetonitrile-water mixed solvent. The aggregation phenomenon has been corroborated by microscopy and light scattering studies. The ligand (L1) also displays a selective turn-on fluorescence response towards human serum albumin (HSA) in 100% aqueous medium over various other comparable proteins (even bovine serum albumin (BSA)) and enzymes. The weakly emissive probe L1 showed a substantial increase in emission intensity upon binding with HSA through electrostatic interactions. The good linear relationship between the fluorescence enhancement (I/I0 - 1) and the concentration of HSA provided the scope to attain an impressive detection limit as low as 5 µg mL-1. A drug displacement experiment and molecular docking study were employed to ascertain the likely protein (HSA)-ligand binding interactions.


Assuntos
Corantes Fluorescentes/química , Albumina Sérica Humana/urina , Ureia/análogos & derivados , Antracenos/síntese química , Antracenos/química , Antracenos/metabolismo , Sítios de Ligação , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/metabolismo , Humanos , Limite de Detecção , Simulação de Acoplamento Molecular , Naftalenos/síntese química , Naftalenos/química , Naftalenos/metabolismo , Ligação Proteica , Albumina Sérica Humana/química , Albumina Sérica Humana/metabolismo , Espectrometria de Fluorescência/métodos , Ureia/síntese química , Ureia/metabolismo
5.
Environ Sci Pollut Res Int ; 26(9): 8675-8684, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30706277

RESUMO

Laccases produced by Leucoagaricus gongylophorus act in lignocellulose degradation and detoxification processes. Therefore, the use of L. gongylophorus laccase (Lac1Lg) was proposed in this work for degradation of anthracene and others polycyclic aromatic hydrocarbons without the use of mediators. Degradation reactions were performed in buffer aqueous solution with 10 ppm of anthracene and other PAHs, Tween-20 in 0.25% v/v and a laccase preparation of 50 U. The optimum condition (pH 6.0 and 30 °C) was determined by response surface methodology with an excellent coefficient of determination (R2) of 0.97 and an adjusted coefficient of determination (R2adj) of 0.93. In addition, the employment of the mediator ABTS decreased the anthracene biodegradation from 44 ± 1% to 30 ± 1%. This optimum pH of 6.0 suggests that the reaction occurs by a hydrogen atom transfer mechanism. Additionally, in 24 h Lac1Lg biodegraded 72 ± 1% anthracene, 40 ± 3% fluorene and 25 ± 3% phenanthrene. The yellow laccase from L. gongylophorus biodegraded anthracene and produced anthrone and anthraquinone, which are interesting compounds for industrial applications. Moreover, this enzyme also biodegraded the PAHs phenanthrene and fluorene justifying the study of Lac1Lg for bioremediation of these compounds in the environment.


Assuntos
Agaricales/metabolismo , Antracenos/metabolismo , Biodegradação Ambiental , Poluentes Ambientais/metabolismo , Lacase/metabolismo , Antraquinonas , Fluorenos , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos/metabolismo
6.
AAPS PharmSciTech ; 20(1): 18, 2019 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-30603884

RESUMO

Nowadays, chemoprevention by administering natural supplements is considered an attractive strategy to reverse, suppress, or prevent the evolution of premalignant oral lesions. In particular, Barbaloin exhibits anti-proliferative, anti-inflammatory, and anti-cancer properties, and it results useful in multi-therapy with classic chemotherapeutics. Therefore, in this work, mucoadhesive buccal films, as locoregional drug delivery system able to provide a targeted and efficient therapeutic delivery of Barbaloin, are proposed. Thus, Aloin extract-loaded Eudragit® RL100 or Eudragit® RS100-based buccal films were designed in order to obtain an easily self-administrable formulation capable of promoting Barbaloin penetration into buccal mucosa and assuring high patient compliance. Large amounts of extract (44%) were loaded into the polymer matrix and six formulations were prepared varying polymers and plasticizers ratios. For all formulations, physical form (thermogravimetric analysis-differential scanning calorimetry, TGA-DSC), swelling degree, mucoadhesiveness, drug release, and ability to promote drug penetration in mucosa have been investigated. After a sequential selection process, Eudragit RS 100-based film, with low PVP and high plasticizers amounts, emerged as the most promising. It results appropriately flexible, uniform in terms of weight, thickness and drug content, as well as characterized by suitable surface pH, good mucoadhesiveness, and low swelling degree. It displays a Higuchian drug release behavior up to 89% of Barbaloin released, thus demonstrating that diffusion through the matrix is the main release mechanism. Remarkable penetration enhancer properties of film were demonstrated by evidence of Barbaloin accumulation into buccal mucosa up to 10-fold higher than those obtained following administration of Aloin solution.


Assuntos
Adesivos/metabolismo , Antracenos/metabolismo , Mucosa Bucal/metabolismo , Polímeros/metabolismo , Resinas Acrílicas/administração & dosagem , Resinas Acrílicas/química , Resinas Acrílicas/metabolismo , Adesivos/administração & dosagem , Administração Bucal , Animais , Antracenos/administração & dosagem , Antracenos/química , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Quimioprevenção/métodos , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Humanos , Mucosa Bucal/efeitos dos fármacos , Polímeros/administração & dosagem , Polímeros/química , Suínos
7.
Chemosphere ; 215: 746-752, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30352372

RESUMO

Understanding the alteration of the air-liquid interfacial properties of pulmonary surfactant (PS) in the presence of nanoparticles (NPs) and polycyclic aromatic hydrocarbons (PAHs) is particularly important for pulmonary risk assessment. Here, we investigated the interaction of natural PS (extracted from pig's lungs) with nano carbon particles (NCPs) and anthracene as a representative PAH. Our results showed that PS exhibited a significant solubilization effect on anthracene. Solubilization experiment for the substructures of PS demonstrated that the mixed phospholipid components of PS played the primary role in the solubilization of PS for anthracene. Adsorption experiment indicated that in the mixed system of PS, NCPs, and anthracene, PS can inhibit the adsorption of anthracene on NCPs due to the solubilization, agglomeration, and competitive adsorption. In addition, the surface tension, phase behavior, and foaming ability of PS were obviously altered in the presence of NCPs. These findings indicate that the solubilization effect of PS on anthracene, the inhibitive effect of PS for the adsorption of anthracene on NCPs, and the alternation of air-liquid interfacial properties of PS containing NCPs may increase the pulmonary risk in the exposure of atmospheric environment containing both PAHs and NCPs.


Assuntos
Antracenos/metabolismo , Carbono/metabolismo , Nanopartículas/metabolismo , Surfactantes Pulmonares/metabolismo , Adsorção , Animais , Carbono/toxicidade , Exposição por Inalação , Micelas , Nanopartículas/toxicidade , Suínos , Testes de Toxicidade
8.
Artigo em Inglês | MEDLINE | ID: mdl-30445288

RESUMO

Anthraquinones and anthrones are the main active components of rhubarb. To investigate the metabolism and possible mutual biotransformations pathways of anthraquinones and anthrones by human intestinal flora, 9 representative constituents (aloe-emodin, rhein, emodin, chrysophanol, physcion, sennosides A, B, C and D) were studied. An ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) with mass spectrometryElevated Energy (MSE) technology was employed to separate and identify their metabolites. As a result, a total of 64 metabolites were identified or characterized from 9 components. Among them, 12 of them were identified by compared with the reference substances, 52 of them were tentatively identified. The results indicated that reduction, hydrolysis, acetylation, oxidation, demethylation, methylation, hydroxylation, dehydroxylation and the bond cleavage of CO and CC were likely to be the metabolic pathways involved in the generation of these metabolites. Moreover, mutual biotransformations existed among the nine representative constituents in rhubarb by human intestinal flora. This study will provide evidences that intestinal flora may play an important role in mediating the bioactivities in vivo of anthraquinones and anthrones in rhubarb.


Assuntos
Antracenos/metabolismo , Antracenos/farmacocinética , Antraquinonas/metabolismo , Antraquinonas/farmacocinética , Microbioma Gastrointestinal/fisiologia , Rheum/química , Antracenos/química , Antraquinonas/química , Fenômenos Bioquímicos , Biotransformação , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Espectrometria de Massas em Tandem/métodos
9.
J Microbiol Biotechnol ; 29(1): 79-90, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30518016

RESUMO

Lichens are generally known as self-sufficient, symbiotic life-forms between fungi and algae/cyanobacteria, and they also provide shelter for a wide range of beneficial bacteria. Currently, bacterial-derived biodegradable polyhydroxyalkanoate (PHA) is grabbing the attention of many researchers as a promising alternative to non-degradable plastics. This study was conducted to develop a new method of PHA production using unexplored lichen-associated bacteria, which can simultaneously degrade two ubiquitous industrial toxins, anthracene and naphthalene. Here, 49 lichen-associated bacteria were isolated and tested for PHA synthesis. During the GC-MS analysis, a potential strain of EL19 was found to be a 3-hydroxyhexanoate (3-HHx) accumulator and identified as Pseudomonas sp. based on the 16S rRNA sequencing. GC analysis revealed that EL19 was capable of accumulating 30.62% and 19.63% of 3-HHx from naphthalene and anthracene, respectively, resulting in significant degradation of 98% and 96% of naphthalene and anthracene, respectively, within seven days. Moreover, the highly expressed phaC gene verified the genetic basis of PHAmcl production under nitrogen starvation conditions. Thus, this study strongly supports the hypothesis that lichen-associated bacteria can detoxify naphthalene and anthracene, store energy for extreme conditions, and probably help the associated lichen to live in extreme conditions. So far, this is the first investigation of lichen-associated bacteria that might utilize harmful toxins as feasible supplements and convert anthracene and naphthalene into eco-friendly 3-HHx. Implementation of the developed method would reduce the production cost of PHAmcl while removing harmful waste products from the environment.


Assuntos
Antracenos/metabolismo , Líquens/microbiologia , Naftalenos/metabolismo , Poli-Hidroxialcanoatos/biossíntese , Pseudomonas/metabolismo , Aciltransferases/genética , Biodegradação Ambiental , Caproatos/metabolismo , Meios de Cultura/química , Expressão Gênica , Nitrogênio , Filogenia , Poli-Hidroxialcanoatos/metabolismo , Pseudomonas/classificação , Pseudomonas/genética , Pseudomonas/crescimento & desenvolvimento , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
J Mol Microbiol Biotechnol ; 28(4): 183-189, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30566957

RESUMO

Nowadays, contamination of soil and marine sediments by polycyclic aromatic hydrocarbons (PAHs) has become a serious problem all over the world. Rhodococcus sp. P14 was isolated from sediments with crude oil contaminate and showed degradation ability on various PAHs. The genome of Rhodococcus sp. P14 was sequenced. A gene cluster encoding a ring-hydroxylating dioxygenase Baa related to PAH degradation was identified by bioinformatics. The expression level of gene baaA was increased when P14 was cultured with anthracene, pyrene, phenanthrene, or benz[a]-anthracene as the single carbon source. The recombinant protein Baa was overexpressed in E. coli BL21 (DE3). Further investigations on the recombinant protein Baa in E. coli demonstrated that it was able to oxidize anthracene and benz [a]anthracene, resulting in 9,10-dihydroxyanthracene and 7, 12-dihydroxybenz[a]anthracene as metabolites, respectively. These results indicate that Baa plays an important role in PAH degradation in Rhodococcus sp. P14 and Baa has potential application in the bioremediation of PAHs in the contaminated environment.


Assuntos
Antracenos/metabolismo , Dioxigenases/genética , Dioxigenases/metabolismo , Rhodococcus/genética , Rhodococcus/metabolismo , Sequência de Bases , Biodegradação Ambiental , Dioxigenases/classificação , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Sedimentos Geológicos/microbiologia , Hidroxilação , Família Multigênica , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Pirenos , Proteínas Recombinantes/genética , Alinhamento de Sequência
11.
Sci Rep ; 8(1): 14844, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30287882

RESUMO

Engineered odorant-binding proteins (OBPs) display tunable binding affinities triggered by temperature alterations. We designed and produced two engineered proteins based on OBP-I sequence: truncated OBP (tOBP) and OBP::GQ20::SP-DS3. The binding affinity of 1-aminoanthracene (1-AMA) to these proteins revealed that tOBP presents higher affinity at 25 °C (kd = 0.45 µM) than at 37 °C (kd = 1.72 µM). OBP::GQ20::SP-DS3 showed an opposite behavior, revealing higher affinity at 37 °C (kd = 0.58 µM) than at 25 °C (kd = 1.17 µM). We set-up a system containing both proteins to evaluate their temperature-dependent binding. Our data proved the 1-AMA differential and reversible affinity towards OBPs, triggered by temperature changes. The variations of the binding pocket size with temperature, confirmed by molecular modelling studies, were determinant for the differential binding of the engineered OBPs. Herein we described for the first time a competitive temperature-dependent mechanism for this class of proteins.


Assuntos
Antracenos/metabolismo , Receptores Odorantes/metabolismo , Temperatura Ambiente , Sequência de Aminoácidos , Aminoácidos , Animais , Sítios de Ligação , Modelos Moleculares , Conformação Molecular , Ligação Proteica , Engenharia de Proteínas , Receptores Odorantes/química , Receptores Odorantes/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Análise Espectral , Relação Estrutura-Atividade , Suínos
12.
World J Microbiol Biotechnol ; 34(9): 133, 2018 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-30109517

RESUMO

The ability of the litter-decomposing basidiomycete Stropharia rugosoannulata DSM 11372 to degrade a wide range of structurally different environmental pollutants such as polycyclic aromatic hydrocarbons (PAHs: phenanthrene, anthracene, fluorene, pyrene, and fluoranthene), synthetic anthraquinone dyes containing condensed aromatic rings, environmentally relevant alkylphenol and oxyethylated alkylphenol representatives, and oil was demonstrated within the present study. 9,10-Anthraquinone, phenanthrene-9,10-quinone, and 9-fluorenone were identified as products of anthracene, phenanthrene, and fluorene degradation, respectively. Fungal degradation was accompanied by the production of the ligninolytic enzymes: laccase and Mn peroxidase, suggesting their involvement in pollutant degradation. Extracellular polysaccharide(s) (EPS) and emulsifying compound(s) were concomitantly produced. EPS composed of mannose, glucose, and galactose was isolated from the cultivation medium, and its effects on catalytic properties of purified laccase from S. rugosoannulata (the dominating ligninolytic enzyme under the applied conditions) were studied. A simultaneous decrease of KM and Vmax values observed for the enzymatic oxidation of non-phenolic (2,2-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) diammonium salt; ABTS) and phenolic compounds (2,6-dimethoxyphenol) in presence of EPS suggest an interaction of EPS and laccase resulting in a modulation of the catalytic performance of the enzyme, which has, to the best of our knowledge, not been reported before. In line with such a modulation, the laccase-catalyzed oxidation of natural aromatic compounds (veratryl alcohol, adlerol) and environmental pollutants (the alkylphenol representative nonylphenol, the diphenylmethane derivative bisphenol A, and the PAH representative anthracene) was found to be enhanced in presence of EPS. The relevance of such effects for real environmental processes and their implications remain to be investigated.


Assuntos
Adaptação Fisiológica , Agaricales/enzimologia , Agaricales/fisiologia , Biodegradação Ambiental , Poluentes do Solo/metabolismo , Antracenos/metabolismo , Compostos Benzidrílicos/metabolismo , Biotransformação , Poluentes Ambientais , Fluorenos/metabolismo , Hidrocarbonetos Cíclicos/metabolismo , Lacase/metabolismo , Oxirredução , Peroxidases/metabolismo , Fenantrenos/metabolismo , Fenóis/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Pirenos/metabolismo
13.
PLoS One ; 13(8): e0201620, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30071070

RESUMO

Biodegradation of hazardous pollutants is of immense importance for maintaining a clean environment. However, the concentration of such contaminants/pollutants can be minimized with the help of microorganisms that has the ability to degrade the toxic pollutants into non-toxic metabolites. In the current study, 23 bacterial isolates were purified from the rhizospheric soil of Sysimbrium irio, growing as a wild plant in the vicinity of gas filling stations in Peshawar city. The isolated strains were initially screened on solid nutrient agar and further purified by culturing it on anthracene amended mineral media (PNR). The bacterial growth and anthracene disappearance were observed by calculating optical density (OD). The isolates showed a concentration-dependent growth on anthracene amended PNR media at 30°C and pH7. Also, an increase in bacterial OD from 0.351 to 1.80 with increased shaking speed was noticed. On the contrary, alternate carbon sources (glucose, fructose, sucrose) or nitrogen sources (KNO3, NaNO3, NH4NO3 and CaNO3) posed inhibitory effect on bacterial growth during anthracene degradation. The recorded efficiency of anthracene degradation by the selected bacterial isolate (1.4×1023 CFUmL-1 and 1.80 OD) was 82.29%, after 120 h of incubation. The anthracene was degraded to 9, 10, dihydroxy-anthracene and anthraquinone, detected through GC-MS. The efficient bacterial isolate was identified as S13, a new strain of Bacillus cereus, using 16S rRNA analysis, showing 98% homology. The isolated bacterial strain S13 may be used as a potential tool for bioremediation of toxic hydrocarbons and to keep the environment free from PAH pollutants.


Assuntos
Antracenos/metabolismo , Bacillus cereus/metabolismo , Antracenos/química , Antraquinonas/análise , Bacillus cereus/classificação , Bacillus cereus/genética , Bacillus cereus/isolamento & purificação , Biodegradação Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Filogenia , RNA Ribossômico 16S/classificação , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Microbiologia do Solo , Poluentes do Solo/química , Poluentes do Solo/metabolismo , Temperatura Ambiente
14.
Biophys Chem ; 242: 1-5, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30153504

RESUMO

The binding and photochirogenic behaviour of 2-anthracenecarboxylate (AC) with human serum albumin (HSA) have hitherto been investigated and comprehended as time-averaged statistical events by spectroscopic examinations and product analyses. In this study, we employed a diffracted X-ray tracking (DXT) technique to visualize the single-molecular dynamics of free and AC-loaded HSA (AC:HSA = 0, 1, 5 and 10), as well as the AC-HSA complex under photoirradiation, all of which were tethered to gold nanocrystals and hence traceable in real time by DXT. This enabled us to draw a more dynamic picture of the bio-supramolecular photochirogenesis at a single-molecule resolution, detailing the softening and flexibility enhancement of HSA upon binding of ACs to its inter-subdomain IIA-IIB site and the dynamic extrusion of AC dimers produced upon photoirradiation.


Assuntos
Antracenos/química , Ácidos Carboxílicos/química , Antracenos/metabolismo , Ácidos Carboxílicos/metabolismo , Dimerização , Ouro/química , Humanos , Lasers de Estado Sólido , Nanopartículas Metálicas/química , Ligação Proteica , Albumina Sérica/química , Albumina Sérica/metabolismo , Estereoisomerismo , Difração de Raios X
15.
Biodegradation ; 29(5): 463-471, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30003496

RESUMO

Although ecological flexibility has been well documented in fungi, it remains unclear how this flexibility can be exploited for pollutant degradation, especially in the Ascomycota phylum. In this work, we assess three mycostimulation amendments for their ability to induce degradation in Trichoderma harzanium, a model fungus previously isolated from a Superfund site contaminated with polycyclic aromatic hydrocarbons. The amendments used in the present study were selected based on the documented ecological roles of ascomycetes. Chitin was selected to simulate the parasitic ecological role while cellulose and wood were selected to mimic bulk soil and wood saprobic conditions, respectively. Each amendment was tested in liquid basal medium in 0.1 and 1% (w/v) suspensions. Both chitin and cellulose amendments were shown to promote anthracene degradation in T. harzanium with the 0.1% chitin amendment resulting in over 90% removal of anthracene. None of the targets monitored for gene expression were found to be upregulated suggesting alternate pathways may be used in T. harzanium. Overall, our data suggest that mycostimulation amendments can be improved by understanding the ecological roles of indigenous fungi. However, further research is needed to better estimate specific amendment requirements for a broader group of target fungi and follow up studies are needed to determine whether the trends observed herein translate to more realistic soil systems.


Assuntos
Ascomicetos/metabolismo , Biodegradação Ambiental , Carbono/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Trichoderma/metabolismo , Antracenos/análise , Antracenos/metabolismo , Ascomicetos/enzimologia , Ascomicetos/genética , Reatores Biológicos , Quitina/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Microbiologia do Solo , Poluentes do Solo , Trichoderma/enzimologia , Trichoderma/genética
16.
Molecules ; 23(7)2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-29996524

RESUMO

Leishmaniasis is a vector-borne disease caused by protozoal Leishmania. Because of resistance development against current drugs, new antileishmanial compounds are urgently needed. Endoperoxides (EPs) are successfully used in malaria therapy, and experimental evidence of their potential against leishmaniasis exists. Anthracene endoperoxides (AcEPs) have so far been only technically used and not explored for their leishmanicidal potential. This study verified the in vitro efficiency and mechanism of AcEPs against both Leishmania promastigotes and axenic amastigotes (L. tarentolae and L. donovani) as well as their toxicity in J774 macrophages. Additionally, the kinetics and radical products of AcEPs' reaction with iron, the formation of radicals by AcEPs in Leishmania, as well as the resulting impairment of parasite mitochondrial functions were studied. Using electron paramagnetic resonance combined with spin trapping, photometry, and fluorescence-based oximetry, AcEPs were demonstrated to (i) show antileishmanial activity in vitro at IC50 values in a low micromolar range, (ii) exhibit host cell toxicity in J774 macrophages, (iii) react rapidly with iron (II) resulting in the formation of oxygen- and carbon-centered radicals, (iv) produce carbon-centered radicals which could secondarily trigger superoxide radical formation in Leishmania, and (v) impair mitochondrial functions in Leishmania during parasite killing. Overall, the data of different AcEPs demonstrate that their structures besides the peroxo bridge strongly influence their activity and mechanism of their antileishmanial action.


Assuntos
Antracenos/metabolismo , Leishmania/metabolismo , Mitocôndrias/metabolismo , Peróxidos/metabolismo , Animais , Antracenos/química , Linhagem Celular , Sobrevivência Celular , Espectroscopia de Ressonância de Spin Eletrônica , Concentração Inibidora 50 , Ferro/farmacologia , Leishmania/efeitos dos fármacos , Camundongos , Mitocôndrias/efeitos dos fármacos , Oxirredução , Consumo de Oxigênio/efeitos dos fármacos , Peróxidos/química , Superóxidos/metabolismo
17.
J Nat Prod ; 81(7): 1570-1577, 2018 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-30015485

RESUMO

Four known compounds, rishirilide B (1), rishirilide C (2), lupinacidin A (3), and galvaquinone B (4), representing two anthracene scaffolds typical of aromatic polyketides, were isolated from a culture of the deep-sea-derived Streptomyces olivaceus SCSIO T05. From the S. olivaceus producer was cloned and sequenced the rsd biosynthetic gene cluster (BGC) that drives rishirilide biosynthesis. The structural gene rsdK2 inactivation and heterologous expression of the rsd BGC confirmed the single rsd BGC encodes construction of 1-4 and, thus, accounts for two anthracene scaffolds. Precursor incubation experiments with 13C-labeled acetate revealed that a Baeyer-Villiger-type rearrangement plays a central role in construction of 1-4. Two luciferase monooxygenase components, along with a reductase component, are presumably involved in the Baeyer-Villiger-type rearrangement reaction enabling access to the two anthracene scaffold variants. Engineering of the rsd BGC unveiled three SARP family transcriptional regulators, enhancing anthracene production. Inactivation of rsdR4, a MarR family transcriptional regulator, failed to impact production of 1-4, although production of 3 was slightly improved; most importantly rsdR4 inactivation led to the new adduct 6 in high titer. Notably, inactivation of rsdH, a putative amidohydrolase, substantially improved the overall titers of 1-4 by more than 4-fold.


Assuntos
Antracenos/isolamento & purificação , Genes Bacterianos , Família Multigênica , Streptomyces/genética , Antracenos/metabolismo , Rearranjo Gênico , Oceanos e Mares , Microbiologia da Água
18.
Biotechnol Lett ; 40(9-10): 1329-1333, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29802569

RESUMO

OBJECTIVES: To improve the quality of diesel fuel via removal of aromatic compounds using Pseudomonas sp. RESULTS: In the present study Pseudomonas sp. was able to remove 94% of fluorene, 59% of phenanthrene, 49% of anthracene, 52% of fluoranthene, 45% of pyrene and 75% carbazole present in diesel oil. Additionally, it also does not affect the aliphatic content of fuel thus maintaining the carbon backbone of the fuel. CONCLUSIONS: Pseudomonas sp. is a potential biocatalyst that can be used in the refining industry.


Assuntos
Biotecnologia/métodos , Gasolina , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Pseudomonas/metabolismo , Antracenos/metabolismo , Biodegradação Ambiental , Carbazóis/metabolismo , Fluorenos/metabolismo , Fenantrenos/metabolismo
19.
J Chem Theory Comput ; 14(6): 2895-2909, 2018 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-29771515

RESUMO

Prediction of membrane permeability to small molecules represents an important aspect of drug discovery. First-principles calculations of this quantity require an accurate description of both the thermodynamics and kinetics that underlie translocation of the permeant across the lipid bilayer. In this contribution, the membrane permeability to three drugs, or drug-like molecules, namely, 9-anthroic acid (ANA), 2',3'-dideoxyadenosine (DDA), and hydrocortisone (HYL), are estimated in a pure 1-palmitoyl-2-oleoylphosphatidylcholine (POPC) and in a POPC:cholesterol (2:1) mixture. On the basis of independent 2-5-µs free-energy calculations combined with a time-fractional Smoluchowski determination of the diffusivity, the estimated membrane permeabilities to these chemically diverse permeants fall within an order of magnitude from the experimental values obtained in egg-lecithin bilayers, with the exception of HYL in pure POPC. This exception is particularly interesting because the calculated permeability of the sterol-rich bilayer to HYL, in close agreement with the experimental value, is about 600 times lower than that of the pure POPC bilayer to HYL. In contrast, the permeabilities to ANA and DDA differ by less than a factor of 10 between the pure POPC and POPC:cholesterol bilayers. The unusual behavior of HYL, a large, amphiphilic compound, may be linked with the longer range perturbation of the lipid bilayer it induces, compared to ANA and DDA, suggestive of a possibly different translocation mechanism. We find that the tendency of lower permeabilities of the POPC:cholesterol bilayer relative to those of the pure POPC one is a consequence of increased free-energy barriers. Beyond reporting accurate estimates of the membrane permeability, the present contribution also demonstrates that rigorous free-energy calculations and a fractional-diffusion model are key in revealing the molecular phenomena linking the composition of a membrane to its permeability to drugs.


Assuntos
Antracenos/metabolismo , Didesoxiadenosina/metabolismo , Hidrocortisona/metabolismo , Bicamadas Lipídicas/metabolismo , Antracenos/química , Colesterol/química , Didesoxiadenosina/química , Hidrocortisona/química , Cinética , Bicamadas Lipídicas/química , Simulação de Dinâmica Molecular , Permeabilidade , Fosfatidilcolinas/química , Termodinâmica
20.
Methods Enzymol ; 603: 93-101, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29673536

RESUMO

Methods for using exogenous fluorophore and general anesthetic 1-aminoanthracene (1-AMA) and its photoactive derivative 1-azidoanthracene (1-AZA) are provided. 1-AMA potentiates GABAA chloride currents and immobilizes Xenopus laevis tadpoles. Cellular and tissue anesthetic distribution can be imaged for quantifying "on-pathway" and "off-pathway" targets. 1-AZA shares targets with 1-AMA and offers further optoanesthetic spatial and temporal control upon near-UV laser irradiation. Furthermore, 1-AZA adduction provides screening of possible relevant anesthetic protein targets and binding site characterization. We highlight several useful imaging and binding assays to demonstrate utility of 1-AMA and its derivative 1-AZA.


Assuntos
Anestésicos Gerais/química , Antracenos/química , Azidas/química , Larva/metabolismo , Receptores de GABA-A/química , Anestésicos Gerais/metabolismo , Animais , Antracenos/metabolismo , Azidas/metabolismo , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Larva/crescimento & desenvolvimento , Larva/ultraestrutura , Lasers , Microscopia de Fluorescência , Processos Fotoquímicos , Ligação Proteica , Receptores de GABA-A/metabolismo , Raios Ultravioleta , Xenopus laevis/anatomia & histologia , Xenopus laevis/crescimento & desenvolvimento , Xenopus laevis/metabolismo
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