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1.
Ecotoxicol Environ Saf ; 193: 110335, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32088549

RESUMO

In this study, mutant CotA-laccase SF was successfully expressed in Escherichia coli by co-expression with phospholipase C. The optimized extracellular expression of CotA-laccase SF was 1257.22 U/L. Extracellularly expressed CotA-laccase SF exhibits enzymatic properties similar to intracellular CotA-laccase SF. CotA-laccase SF could decolorize malachite green (MG) under neutral and alkaline conditions. The Km and kcat values of CotA-laccase SF to MG were 39.6 mM and 18.36 s-1. LC-MS analysis of degradation products showed that MG was finally transformed into 4-aminobenzophenone and 4-aminophenol by CotA-laccase. The toxicity experiment of garlic root tip cell showed that the toxicity of MG metabolites decreased. In summary, CotA-laccase SF had a good application prospect for degrading malachite green.


Assuntos
Corantes/metabolismo , Lacase/metabolismo , Corantes de Rosanilina/metabolismo , Corantes/toxicidade , Escherichia coli/genética , Escherichia coli/metabolismo , Lacase/genética , Mutação , Corantes de Rosanilina/toxicidade
2.
Medicine (Baltimore) ; 99(2): e18467, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914018

RESUMO

BACKGROUND: Curcumin, a controversial "panacea," has been broadly studied. Its bioactivities including antioxidant, anti-inflammatory, and especially antineoplastic activities have been documented. However, due to its extensive bioactivities, some scientists hold a skeptical point of view toward curcumin and described curcumin as a "deceiver" to chemists. The objective of this study was to explore curcumin's another possibility as a potential supplementary leading compound to cancer treatments. METHODS: Literature searches were conducted using electronic databases. Search terms such as "curcumin," "curcumin analogues," and so on were used. The literatures were collected and summarized. In this article, reported targets of curcumin are reviewed. The limitations of a curcumin as a therapeutic anticancer product including low bioavailability and poor targeting are mentioned. Furthermore, modified curcumin analogues and antitumor mechanisms are listed and discussed in the aspects of cell death and tumor microenvironment including angiogenesis, tissue hypoxia status, and energy metabolism. RESULTS: Several possible modification strategies were presented by analyzing the relationships between the antitumor activity of curcumin analogues and their structural characteristics, including the introduction of hydrophilic group, shortening of redundant hydrocarbon chain, the introduction of extra chemical group, and so on. CONCLUSIONS: From our perspective, after structural modification curcumin could be more effective complementary product for cancer therapies by the enhancement of targeting abilities and the improvement of bioavailability.


Assuntos
Corantes/metabolismo , Corantes/farmacologia , Curcumina/metabolismo , Curcumina/farmacologia , Antineoplásicos , Disponibilidade Biológica , Morte Celular/efeitos dos fármacos , Terapias Complementares , Curcumina/química , Humanos , Neoplasias/tratamento farmacológico , Microambiente Tumoral/efeitos dos fármacos
3.
Ecotoxicol Environ Saf ; 191: 110184, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31935556

RESUMO

Laccases play a significant role in remedying dye pollutants. Most of these enzymes are originated from terrestrial fungi and bacteria, thus they are not proper to be used in the environments with neutral/alkaline pH, or they may require laborious extraction/purification steps. These limitations can be solved using marine spore laccases through high stability and easy to use application. In the current study, laccase activity of the marine spore -forming Bacillus sp. KC2 was measured according to the guaiacol and syringaldazine oxidation. Abiotic stresses like pH of 6, temperature of 37 °C and 0.3 mM CuSO4 (in comparison with optimal sporulation conditions: pH of 8, temperature of 20 °C and 0.0 mM CuSO4) enhanced laccase formation in sporal coat. Maximum activity of enzyme was observed at 50 °C and pH 7, which did not change in the alkaline pH and temperature range of 20-70 °C. Results indicated ions, inhibitors and solvent stability of the enzyme and its activity were stimulated by Co2+, Mn2+, PMSF, acetone, acetonitrile, ethanol, and methanol. The spore laccase could decolorize synthetic dyes from various chemical groups including azo (acid orange, amaranth, trypan blue, congo red, and amido black), indigo (indigo carmine), thiazine (methylene blue, and toluidine blue), and triarylmethane (malachite green) with ABTS/syringaldazine mediators after 5 h. Degradation products were not toxic against Sorghum vulgare and Artemia salina model organisms. The enzyme mediator system showed high potentials for dye bioremediation over a wide range of harsh conditions.


Assuntos
Corantes/metabolismo , Lacase/metabolismo , Água do Mar/microbiologia , Esporos Bacterianos/enzimologia , Poluentes Químicos da Água/metabolismo , Bacillus/enzimologia , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Oxirredução , Temperatura
4.
Chemosphere ; 246: 125753, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31901528

RESUMO

Granules which could efficiently mineralize azo dyes were cultivated through immobilization of aerobic degradation strains in a core composed of anaerobic decolorization cultures. The core was obtained in a up-flow anaerobic sludge blanket (UASB) reactor incubated with anaerobic decolorization bacteria. Aerobic degradation strains were then grown on the surface of the anaerobic core in a sequencing batch reactor (SBR). Three of the granules' surface layers demonstrated the occurrence of immobilization. The granulation process was monitored with 16S rDNA high throughput sequencing. Anaerobic decolorization cultures belonging to the genera of unclassified, Levilinea, and Petrimonas and the aerobic degradation genera of Thauera, unclassified, Thermomonas, and Ottowia were successfully fixed in the granules. The obtained granules were capable of decolorizing azo dyes under anaerobic situation, and the generated aromatic amines were then completely mineralized in aerated environment. Comparative studies on the relationship between removed contaminates and typical components concentrations in low to high strength azo dye wastewater showed that the granules have great potentials in treating wastewater with different complexity. The removal efficiency of COD and TOC was not restricted by loading concentrations.


Assuntos
Compostos Azo/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Aminas/metabolismo , Anaerobiose , Compostos Azo/análise , Bactérias Anaeróbias/metabolismo , Reatores Biológicos , Corantes/metabolismo , Esgotos/microbiologia , Águas Residuárias , Poluentes Químicos da Água/análise
5.
Ecotoxicol Environ Saf ; 191: 110203, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31972453

RESUMO

The aim of this study was to evaluate of possibility of biotransformation and toxicity effect of monoanthraquinone dyes in cultures of Bjerkandera adusta CCBAS 930. Phenolic compounds, free radicals, phytotoxicity (Lepidium sativum L.), ecotoxicity (Vibrio fischeri) and cytotoxicity effect were evaluated to determine the toxicity of anthraquinone dyes before and after the treatment with B. adusta CCBAS 930. More than 80% of ABBB and AB129 was removed by biodegradation (decolorization) and biosorption, but biodegradation using oxidoreductases was the main dye removing mechanism. Secondary products toxic to plants and bacteria were formed in B. adusta strain CCBAS 930 cultures, despite efficient decolorization. ABBB and AB129 metabolites increased reactive oxygen species (ROS) production in human fibroblasts, but did not increase LDH release, did not affect the resazurine reduction assay and did not change caspase-9 or caspase-3 activity.


Assuntos
Antraquinonas/metabolismo , Antraquinonas/toxicidade , Corantes/metabolismo , Corantes/toxicidade , Coriolaceae/metabolismo , Aliivibrio fischeri/efeitos dos fármacos , Biodegradação Ambiental , Biotransformação , Corantes/química , Humanos , Lepidium sativum/efeitos dos fármacos , Fenóis/análise
6.
Chemosphere ; 238: 124538, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31454745

RESUMO

Although banned, dyes, such as Victoria pure blue BO (VPBO), are illicitly used in aquaculture to treat or prevent infections due to their therapeutic activities. The present study examined the formation of phase I and phase II metabolites derived from VPBO using trout liver microsomes and S9 proteins. The well-known malachite green (MG) dye was also studied as a positive control and to compare its metabolism with that of VPBO. First, we optimised the incubation conditions for the detection of VPBO and MG metabolites by studying the formation of cytochrome P450 (CYP) substrates. Using the determined conditions (2 h at 20 °C), we incubated VPBO with trout microsomal and S9 fractions induced with ß-naphtoflavone, and analysed the supernatant in a LC-LTQ-Orbitrap-HRMS system. The in vitro assays led to the detection of 16 VPBO metabolites from Phase I reactions, arising in particular from reactions with CYP1A. No metabolites were detected from Phase II reactions. The main metabolite detected, deethyl-VPBO, was CID-fragmented to determine its chemical structure, and thus recommend a potential biomarker for the control of VPBO in farmed fish foodstuffs.


Assuntos
Corantes/metabolismo , Peixes/metabolismo , Contaminação de Alimentos/análise , Compostos de Amônio Quaternário/metabolismo , Alimentos Marinhos , Animais , Aquicultura , Sistema Enzimático do Citocromo P-450/metabolismo , Metabolômica , Microssomos Hepáticos/metabolismo
7.
Chemosphere ; 238: 124539, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31470310

RESUMO

The performance and microbial community structure of anaerobic dynamic membrane bioreactor (AnDMBR) treating textile wastewater was investigated. The reactor showed excellent soluble COD and color removal of 98.5% and >97.5%, respectively. Dynamic membrane layer grown over the 3D printed dynamic membrane support showed decent rejection for high molecular weight compounds (>20 kDa); and the total suspended solid rejection by the dynamic layer was >98.8%. Gel permeation chromatography analysis of extracellular polymeric substance (EPS) and effluent samples revealed EPS accounted for more than 76.7% of low molecular weight fractions (<20 kDa) that end up in the effluent. Higher applied flux facilitated the rapid formation dynamic layer which enabled a satisfactory effluent quality. Microbial community analysis revealed that during the operation the archaeal community was relatively stable while obvious changes took place in the bacterial community. Introduction of dye Remazol Brilliant Blue R (RBBR) to the AnDMBR increased the abundances of phyla of Proteobacteria and Spirochaetae whereas fractions of Firmicutes and Euryarchaeota decreased obviously. Furthermore, relative stable abundances of phyla Aminicenantes, Bacteroidetes, Thermotogae and Chloroflexi among the top six phyla detected in the system ensured a healthy anaerobic degradation environment for RBBR wastewater treatment.


Assuntos
Antraquinonas/isolamento & purificação , Antraquinonas/metabolismo , Reatores Biológicos/microbiologia , Membranas Artificiais , Têxteis , Águas Residuárias/química , Anaerobiose , Corantes/isolamento & purificação , Corantes/metabolismo , Matriz Extracelular de Substâncias Poliméricas/microbiologia , Proteobactérias/metabolismo , Spirochaeta/metabolismo , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/metabolismo
8.
Biosci Biotechnol Biochem ; 84(1): 103-110, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31559912

RESUMO

We previously reported that MDA-MB-231 and MCF-7 cells, which are breast cancer cell lines and have cancer and cancer-initiating cells (CICs), were killed following normothermic microwave irradiation in which the cellular temperature was maintained at 37°C. In this study, we investigated the percentages of live or dead cells among CD44+/CD24- cells, which were defined as CICs among MDA-MB-231 and MCF-7 cells, and other types of cells in response to microwave irradiation. CD44+/CD24- cells among MDA-MB-231 cells were killed, thereby decreasing the number of cells, whereas the number of live CD44+/CD24- MCF-7 cells was increased following microwave irradiation. Moreover, adhesion, invasion, and migration were decreased in MDA-MB-231 cells, and the activation of matrix metalloproteinase-2 (MMP-2) in MDA-MB-231 cells was increased following microwave irradiation. These decreased cell activities might have been caused by MMP-2 activation and population changes in CD44+/CD24- in MDA-MB-231 cells.Abbreviations: APC: allophecocyanin; CBB: coomassie Brilliant Blue; CD: cluster of differentiation; CICs: cancer-initiating cells; FACS: fluorescence-activated cell sorting; FBS: fetal bovine serum; FITC: fluorescein isothiocyanate; FTDT: finite-difference time domain; HER2: human epidermal growth factor receptor type 2; PI: propidium iodide.


Assuntos
Antígeno CD24/metabolismo , Adesão Celular/efeitos da radiação , Movimento Celular/efeitos da radiação , Receptores de Hialuronatos/metabolismo , Micro-Ondas , Neoplasias de Mama Triplo Negativas/patologia , Apoptose/efeitos da radiação , Contagem de Células , Corantes/metabolismo , Feminino , Citometria de Fluxo , Humanos , Células MCF-7 , Metaloproteinase 2 da Matriz/metabolismo , Invasividade Neoplásica , Propídio/metabolismo , Temperatura
9.
Chemosphere ; 239: 124787, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31526987

RESUMO

Herein, the mutual effect between azo dye and the performance of electrochemically active bacteria (EAB) is investigated in detail, which is crucial to understand and control the bio-electrochemical systems (BESs) operation for azo dye containing wastewater treatment. EAB is enriched at controlled potential of -0.2 V vs Ag/AgCl in single-chamber BESs. Over 95% azo dye (alizarin yellow R (AYR)) was decolorized regardless of the initial AYR concentration ranging from 30 to 120 mg/L within 24 h. The fastest decolorization rate was obtained at AYR initial concentration of 70 mg/L, which was 4.25 times greater in the closed circuit BESs than that in the open circuit one. 16S rRNA gene based microbial community analysis showed that Geobacter was dominant in EAB with relative abundance increased from 77.98% (0 mg/L AYR) to 92.22% (70 mg/L AYR), indicating that azo dye selectively boosts the growth of exoelectrogens in electrode biofilm communities. Under electricity stimulation, extracellular process can be mutually conducted by azo dye compounds, which is favorable for accelerating reaction rate and avoiding of significant toxic effect on EAB.


Assuntos
Compostos Azo/química , Bactérias/química , Corantes/química , Eliminação de Resíduos Líquidos/métodos , Compostos Azo/metabolismo , Bactérias/genética , Bactérias/metabolismo , Biofilmes , Cor , Corantes/metabolismo , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos/microbiologia , Geobacter/genética , Geobacter/metabolismo , Microbiota/genética , RNA Ribossômico 16S , Águas Residuárias/química
10.
Protein Pept Lett ; 27(1): 74-84, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31385759

RESUMO

BACKGROUND: Marine sessile organisms display a color palette that is the result of the expression of fluorescent and non-fluorescent proteins. Fluorescent proteins have uncovered transcriptional regulation, subcellular localization of proteins, and the fate of cells during development. Chromoproteins have received less attention until recent years as bioreporters. Here, we studied the properties of aeBlue, a a 25.91 kDa protein from the anemone Actinia equina. OBJECTIVE: To assess the properties of aeBlue chromoprotein under different physicochemical conditions. METHODS: In this article, during the purification of aeBlue we uncovered that it suffered a color shift when frozen. We studied the color shift by different temperature incubation and physicochemical conditions and light spectroscopy. To assess the possible structural changes in the protein, circular dichroism analysis, size exclusion chromatography and native PAGE was performed. RESULTS: We uncover that aeBlue chromoprotein, when expressed from a synthetic construct in Escherichia coli, showed a temperature dependent color shift. Protein purified at 4 °C by metal affinity chromatography exhibited a pinkish color and shifts back at higher temperatures to its intense blue color. Circular dichroism analysis revealed that the structure in the pink form of the protein has reduced secondary structure at 4 °C, but at 35 °C and higher, the structure shifts to a native conformation and Far UV- vis CD spectra revealed the shift in an aromatic residue of the chromophore. Also, the chromophore retains its properties in a wide range of conditions (pH, denaturants, reducing and oxidants agents). Quaternary structure is also maintained as a tetrameric conformation as shown by native gel and size exclusion chromatography. CONCLUSION: Our results suggest that the chromophore position in aeBlue is shifted from its native position rendering the pink color and the process to return it to its native blue conformation is temperature dependent.


Assuntos
Corantes/química , Proteínas Luminescentes/química , Pigmentos Biológicos/química , Proteínas/química , Anêmonas-do-Mar/química , Sequência de Aminoácidos , Animais , Clonagem Molecular , Cor , Corantes/metabolismo , Escherichia coli/metabolismo , Expressão Gênica , Concentração de Íons de Hidrogênio , Luz , Proteínas Luminescentes/metabolismo , Modelos Moleculares , Oxirredução , Pigmentos Biológicos/metabolismo , Conformação Proteica , Desnaturação Proteica , Proteínas/metabolismo , Espectrofotometria , Temperatura
11.
Enzyme Microb Technol ; 132: 109398, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31731976

RESUMO

Transformation of 2-amino-3-methoxybenzoic acid into novel and eco-friendly orange dye (N15) was performed using native and immobilised laccase (LAC) from Pleurotus ostreatus strain. A several parameters affecting laccase-mediated transformation efficiency included the selection of type and pH value of buffer, reaction temperature, substrate and laccase concentration as well as the type of carrier and LAC storage conditions were evaluated. The optimal conditions for N15 dye synthesis were 40 mM sodium-tartrate buffer pH 5.5 containing 3 mM of the substrate, efficiently transformed by 2 U of free laccase per 1 mmol of the substrate. Laccase was immobilised on porous Purolite® carriers, which had never been tested as a support for oxidoreductases. Immobilised laccase, characterised by a high immobilisation yield, was obtained by adsorption of laccase on a porous acrylic carrier with octadecyl groups (C18) incubated in optimum conditions of 40 mM phosphate buffer pH 7.0 containing 1 mg of laccase per 1 g of the carrier (wet mass). The immobilised LAC showed the highest storage stability for 21 days and higher thermostability at 40 ℃ and 60 ℃ in comparison to its native form. The N15 dye showed good dyeing properties towards natural fibres, and the dyed fibre demonstrated resistance to different physicochemical factors during use, which was confirmed by commercial quality tests. The N15 dye is a phenazine, i.e. a heterogenic compound containing amino-, methoxy-, and three carboxyl functional groups with the molecular weight of approximately 449.37 U.


Assuntos
Corantes/metabolismo , Enzimas Imobilizadas/metabolismo , Lacase/metabolismo , Pleurotus/enzimologia , Ácido Vanílico/análogos & derivados , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Têxteis , Ácido Vanílico/química
12.
Environ Monit Assess ; 191(12): 766, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31754863

RESUMO

Xenobiotic azo dyes and chromate (Cr(VI)) containing industrial wastewaters cause severe ecological problems. The present bioremediation study aims to treat wastewater containing Cr(VI) ions and mixed azo dyes (reactive red 21 (RR21) and reactive orange 16 (RO16)) by Pseudomonas aeruginosa 23N1. The process optimization of bioremediation is investigated using statistical designed experimental tool of response surface methodology. The ANOVA analysis is performed to evaluate optimal biodecolourization condition. This study shows that the amount of yeast extract has major influence on biodecolourization performance. The decolourization of individual RO16 and RR21 dye in presence of 60 mg/L of Cr(VI) ions is obtained as 88.5 ± 0.8 and 92.3 ± 0.7% for 100 and 150 mg/L initial dye concentrations, respectively. In this study, bacteria exhibit high Cr(VI) removal potential of ~ 99.1% against initial Cr(VI) concentration of 150 mg/L. The negative influence of Cr(VI) ions on biodecolourization is only noticed when initial Cr(VI) concentration in wastewater is found above 150 mg/L. The results reveal that bacteria studied here could be used to biodecolourize dyes even in high saline condition (> 6000 mg/L). The reduction of ~ 80% in American Dye Manufacturers Institute colour index value is achieved for mixed dyes solution containing 50 mg/L of both RR21 and RO16 dyes along with 50 mg/L Cr(VI) ions. Significant changes in the UV-visible and ATR-FTIR spectra are observed in treated water that confirms the biodegradation of dyes. Toxicity study with Vigna radiata reveals the non-toxicity of degraded metabolites and strain 23N1 is recommended as an effective bioremediation agent.


Assuntos
Biodegradação Ambiental , Cromo , Corantes , Águas Residuárias , Purificação da Água , Compostos Azo/química , Compostos Azo/metabolismo , Bactérias/metabolismo , Cromo/química , Cromo/metabolismo , Corantes/química , Corantes/metabolismo , Pseudomonas aeruginosa/metabolismo , Águas Residuárias/química , Purificação da Água/métodos
13.
Ecotoxicol Environ Saf ; 184: 109613, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31491606

RESUMO

Four sugar sources were used as co-substrates to promote the degradation of a selected refractory dye reactive black 5 (RB5) by the natural bacterial flora DDMZ1. The boosting performance of the four sugar sources on RB5 decolorization ranked as: fructose > sucrose > glucose > glucose + fructose. Kinetic results of these four co-metabolism systems agreed well with a first-order kinetic model. Four sugar sources stimulated the extracellular azoreductase secretion causing enhanced enzyme activity. An increased formation of low molecular weight intermediates was caused by the addition of sugar sources. The toxicity of RB5 degradation products was significantly reduced in the presence of sugar sources. The bacterial community structure differed remarkably as a result of sugar sources addition. For a fructose addition, a considerably enriched population of the functional species Burkholderia-Paraburkholderia and Klebsiella was noted. The results enlarge our knowledge of the microkinetic and microbiological mechanisms of co-metabolic degradation of refractory pollutants.


Assuntos
Corantes/metabolismo , Naftalenossulfonatos/metabolismo , Açúcares/metabolismo , Bactérias/classificação , Bactérias/metabolismo , Biodegradação Ambiental , Corantes/química , Corantes/toxicidade , Cinética , NADH NADPH Oxirredutases/metabolismo , Naftalenossulfonatos/toxicidade
14.
Ecotoxicol Environ Saf ; 183: 109484, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31398583

RESUMO

This work evaluated the degradation of the Acid Blue 161 and Procion Red MX-5B dyes in a binary solution by the filamentous fungus Aspergillus terreus and the yeast Saccharomyces cerevisiae in systems with and without electrochemical oxidation as the pretreatment process. UV-Vis spectrophotometry, high-performance liquid chromatography with (HPLC), Fourier transform infrared (FT-IR) spectroscopy and Salmonella/microsome assay (Ames test) were applied towards the degradation analysis of the dyes. Adsorption tests with white clay immobilized on alginate were also conducted after the discoloration treatments to remove intermediate metabolites formed during the degradation of the dye molecules. The discoloration treatments led to the complete color removal of the solutions in all the systems tested. The clay demonstrated affinity for the metabolites formed after discoloration treatments, the removal rates were variable, but the all systems has proved efficient. The Salmonella/microsome assay (Ames test) with strains TA98 and TA100 in the absence and presence of exogenous metabolism (S9 microsomal system, Moltox) revealed that the initial molecules and by-products of the metabolism of the dyes were direct mutagens. The electrochemical/A. terreus/clay system was able to discolor the solutions and transform the direct mutagens into non-mutagenic compounds in addition to reducing the mutagenic potency of the pro-mutagens to the Salmonella strain TA100/S9, which demonstrates the high efficiency of this system with regard to discoloring and degrading azo dye molecules and their by-products. Therefore, this study showed that although not having standard treatment system for this type of pollutant, the combination of treatments can be considered promising. The use of electrochemical oxidation along with microbiological treatment may lead to the degradation and mineralization of these compounds, reducing or eliminating the environmental impact caused by the improper disposal of these dyes in aquatic environments.


Assuntos
Compostos Azo/metabolismo , Compostos Azo/toxicidade , Corantes/metabolismo , Corantes/toxicidade , Mutagênicos/metabolismo , Mutagênicos/toxicidade , Aspergillus/metabolismo , Cromatografia Líquida de Alta Pressão , Complexos de Coordenação/metabolismo , Complexos de Coordenação/toxicidade , Naftalenossulfonatos/metabolismo , Naftalenossulfonatos/toxicidade , Oxirredução , Estresse Oxidativo , Saccharomyces cerevisiae/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Microbiol Res ; 228: 126299, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31422231

RESUMO

Wastewaters from textile dyeing industries represent an ecological concern, notably due to the known toxicity of azo dyes to the local microbiome and human health. Although physicochemical approaches are the rule for the treatment of industrial effluents, biological strategies such as enzyme-mediated dye destaining is a promising alternative. Notwithstanding a broad range of microorganisms, including fungi, algae, yeast, and bacteria, display dye-destaining properties, most of the literature has focused in ligninolytic fungi, leaving other classes of organisms somehow ignored. In this study, six endophytic strains isolated from Maytenus ilicifolia were studied for their destaining activity. The phylogenetic and morphological analysis allowed the identification of strain LGMF1504 as Neopestalotiopsis sp. LGMF1504 that decolorized several commercial dyes as the result of a mycelium-associated laccase. The enzyme expression was modulated by carbon and nitrogen content in the culture medium, it was weakly affected by the presence of aromatic compounds and metal ions while some common laccase mediators improved the destaining activity onto dye substrates. The best culture condition observed for laccase activity was a basic culture medium containing 5 g L-1 starch and 15 g L-1 ammonium tartrate. The laccase activity showed low substrate specificity and almost unaltered performance in a wide range of pH values and NaCl concentrations, suggesting the potential of Neopestalotiopsis sp. LGMF1504 for biodegradation approaches.


Assuntos
Corantes/metabolismo , Endófitos/metabolismo , Lacase/metabolismo , Micélio/metabolismo , Compostos Azo/toxicidade , Biodegradação Ambiental , Carbono , Corantes/toxicidade , DNA Fúngico , Endófitos/classificação , Endófitos/isolamento & purificação , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Fungos/metabolismo , Concentração de Íons de Hidrogênio , Metais , Tipagem de Sequências Multilocus , Nitrogênio , Filogenia , Cloreto de Sódio/análise , Indústria Têxtil , Águas Residuárias
16.
Bioresour Technol ; 291: 121875, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31362846

RESUMO

Although a large amount of textile wastewater is discharged at high temperatures, azo dye reduction under extreme-thermophilic conditions by mixed cultures has gained little attention. In this study, Acid Orange 7 (AO7) was used as the model azo dye to demonstrate the decolorization ability of an extreme-thermophilic mixed culture. The results showed that a decolorization efficiency of over 90% was achieved for AO7. The neutral red (NR, 0.1 mM) could promote AO7 decolorization, in which the group of Cell + NR offered the highest decolorization rate of 1.568 1/h and t1/2 was only 0.44 h, whereas after CuCl2 addition, the decolorization rate (0.141 1/h) was lower and t1/2 (4.92 h) was much longer. Thus, CuCl2 notably inhibited this process. Caldanaerobacter (64.0%) and Pseudomonas (25.4%) were the main enriched bacteria, which were not reported to have the ability for dye decolorization. Therefore, this study extends the application of extreme-thermophilic biotechnology.


Assuntos
Archaea/metabolismo , Compostos Azo/metabolismo , Bactérias Anaeróbias/metabolismo , Benzenossulfonatos/metabolismo , Corantes/metabolismo
17.
J Microbiol Biotechnol ; 29(9): 1383-1390, 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31434174

RESUMO

In this study, we expressed cotA laccase from Bacillus subtilis on the surface of B. subtilis spores for efficient decolorization of synthetic dyes. The cotE, cotG, and cotY genes were used as anchoring motifs for efficient spore surface display of cotA laccase. Moreover, a His6 tag was inserted at the C-terminal end of cotA for the immunological detection of the expressed fusion protein. Appropriate expression of the CotE-CotA (74 kDa), CotG-CotA (76 kDa), and CotY-CotA (73 kDa) fusion proteins was confirmed by western blot. We verified the surface expression of each fusion protein on B. subtilis spore by flow cytometry. The decoloration rates of Acid Green 25 (anthraquinone dye) for the recombinant DB104 (pSDJH-EA), DB104 (pSDJH-GA), DB104 (pSDJH-YA), and the control DB104 spores were 48.75%, 16.12%, 21.10%, and 9.96%, respectively. DB104 (pSDJH-EA) showed the highest decolorization of Acid Green 25 and was subsequently tested on other synthetic dyes with different structures. The decolorization rates of the DB104 (pSDJH-EA) spore for Acid Red 18 (azo dye) and indigo carmine (indigo dye) were 18.58% and 43.20%, respectively. The optimum temperature for the decolorization of Acid Green 25 by the DB104 (pSDJH-EA) spore was found to be 50°C. Upon treatment with known laccase inhibitors, including EDTA, SDS, and NaN3, the decolorization rate of Acid Green 25 by the DB104 (pSDJH-EA) spore decreased by 23%, 80%, and 36%, respectively.


Assuntos
Antraquinonas/metabolismo , Bacillus subtilis/enzimologia , Corantes/metabolismo , Lacase/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Inibidores Enzimáticos/química , Expressão Gênica , Cinética , Lacase/antagonistas & inibidores , Lacase/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Esporos Bacterianos/enzimologia , Esporos Bacterianos/genética , Esporos Bacterianos/metabolismo , Temperatura
18.
Appl Microbiol Biotechnol ; 103(17): 6973-6987, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31243502

RESUMO

Some of the most important natural pigments have been produced from fungi and used for coloring in food, cosmetics, textiles, and pharmaceutical products. Forty-seven isolates of endophytic fungi were isolated from Cinnamomum zeylanicum in northern Thailand. Only one isolate, CMU-ZY2045, produced an extracellularly red pigment. This isolate was identified as Nigrospora aurantiaca based on morphological characteristics and the molecular phylogenetic analysis of a combined four loci (large subunit and internal transcribed spacer of ribosomal DNA, ß-tubulin, and translation elongation factor 1-alpha genes). The optimum conditions for red pigment production from this fungus were investigated. The results indicated that the highest red pigment yield was observed in the liquid medium containing glucose as a carbon source and yeast extract as a nitrogen source, at a pH value of 5.0 and at 27 °C with shaking for 5 days. The crude red pigment revealed the highest level of solubility in methanol. A fungal red pigment was found to have high stability at temperatures ranging from 20 to 50 °C and pH values at a range of 5.0-6.0. Based on liquid chromatography-mass spectrometry analyses, the red pigment was characterized as bostrycin. The extracted pigment was used for the textile dyeing process. Crude fungal red pigment revealed the highest staining ability in cotton fabrics and displayed excellent fastness to washing, which showing negative cytotoxicity at the concentrations used to cell culture. This is the first report on bostrycin production from N. aurantiaca.


Assuntos
Ascomicetos/química , Corantes/metabolismo , Pigmentos Biológicos/metabolismo , Têxteis , Antraquinonas/análise , Ascomicetos/classificação , Ascomicetos/genética , Ascomicetos/metabolismo , Carbono/análise , Cinnamomum zeylanicum/microbiologia , Corantes/química , Corantes/isolamento & purificação , Meios de Cultura/química , DNA Ribossômico/genética , Genes Fúngicos/genética , Concentração de Íons de Hidrogênio , Metanol/química , Nitrogênio/análise , Filogenia , Pigmentos Biológicos/química , Pigmentos Biológicos/isolamento & purificação , Solubilidade , Temperatura
19.
Int J Biol Macromol ; 136: 559-569, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31207326

RESUMO

Life manifestation is mainly based on biopolymer-ligand molecular recognition; therefore, the elucidation of energy and speed associated with protein-ligand binding is strategic in understanding and modulating biological systems. In this study, the interactions between methylene blue (MB) or azure A (AZA) dyes and bovine lactoferrin (BLF) were investigated by surface plasmon resonance, fluorescence spectroscopy, and isothermal titration microcalorimetry. Despite the molecular similarities between the dyes, the BLF-AZA binding thermodynamic parameters (ΔGAZAo = -30.50 and ΔHAZAo = 10.8 (kJ·mol-1)) were higher in magnitude than those of the BLF-MB systems (ΔGMBo = -27.3 and ΔHMBo = 5.72 (kJ·mol-1)). To increase the systems' entropy (TΔSAZAo = 41.3 and TΔSMBo = 33.0 (kJ·mol-1)), the hydrophobic interactions must outweigh the electrostatic repulsion, thereby promoting BLF-dye binding. The activation complex formation (Eac, aMB = 33, Eac, aAZA = 32, ∆Ha, MB‡ = 31, ∆Ha, AZA‡ = 30, ∆Ga, MB‡ = 51.84, ∆Ga, AZA‡ = 50.7, T∆Sa, MB‡ = -21, T∆Sa, AZA‡ = -21 (kJ·mol-1)), owing to free BLF and MB (or AZA) associations, was not affected by the dye chemical structure, while for the thermodynamically stable BLF-dye complex dissociation, the same energetic parameters (Eac, dMB = 16, Eac, dAZA = 6.4, ∆Hd, MB‡ = 14, ∆Hd, AZA‡ = 3.9, ∆Gd, MB‡ = 81.4, ∆Gd, AZA‡ = 74.93, T∆Sd, MB‡ = -68, T∆Sd, AZA‡ = -71.0 (kJ·mol-1)) were considerably affected by the number of methyl groups. Our results may be very useful to determine binding processes controlled by kinetic parameters, as well as to optimize the application of these photosensitive dyes in biological systems.


Assuntos
Corantes Azur/metabolismo , Corantes/metabolismo , Lactoferrina/metabolismo , Azul de Metileno/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Ligação Proteica , Ressonância de Plasmônio de Superfície , Termodinâmica
20.
Environ Pollut ; 252(Pt A): 352-365, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31158664

RESUMO

Dyeing wastewaters are toxic and carcinogenic to both aquatic life and human beings. Adsorption technology, as a facile and effective method, has been extensively used for removing dyes from aqueous solutions for decades. Numerous researchers have attempted to seek or design alternative materials for dye adsorption. However, using various novel adsorbents to remove dyes has not been extensively reviewed before. In this review, the key advancement on the preparation and modification of novel adsorbents and their adsorption capacities for dyes removal under various conditions have been highlighted and discussed. Specific adsorption mechanisms and functionalization methods, particularly for increasing adsorption capacities are discussed for each adsorbent. This review article mainly includes (1) the categorization, side effects and removal technologies of dyes; (2) the characteristics, advantages and limitations of each sort of adsorbents; (3) the functionalization and modification methods and controlling mechanisms; and (4) discussion on the problems and future perspectives about adsorption technology from adsorbents aspects and practical application aspects.


Assuntos
Corantes/metabolismo , Recuperação e Remediação Ambiental/métodos , Águas Residuárias/química , Poluentes Químicos da Água/metabolismo , Poluição Química da Água/análise , Adsorção , Corantes/análise , Poluentes Químicos da Água/análise
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