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INTRODUCTION: Tinea corporis (TC; ringworm or dermatophytosis) is a superficial skin infection caused by Microsporum, Epidermophyton and Trichophyton genera of dermatophytes. We compared the effects of individualized homeopathic medicines (IHMs) in fifty-millesimal (LM) potencies against placebo in TC. METHODS: A double-blind, randomized, placebo-controlled, two parallel arms trial was conducted on 62 individuals suffering from TC at the National Institute of Homoeopathy, India. Participants were randomized in a 1:1 ratio to receive either IHMs in LM potencies or identical-looking placebos for a period of 3 months. The primary outcome measure was the number of participants showing complete disappearance of skin lesions after 3 months. Secondary outcomes were a numeric rating scale (NRS) measuring intensity of itching and the Skindex-29 questionnaire (overall, and three sub-scales - degree of symptoms, psychological functioning, emotional status). All were assessed at baseline and every month, up to 3 months. The intention-to-treat sample was analyzed to detect inter-group differences using two-way repeated measures analysis of variance after adjusting for baseline differences. RESULTS: The primary outcome revealed no improvement in either of the groups (χ 2 = 0.012, p = 0.999). Inter-group differences in some of the secondary outcomes favored IHMs against placebo - itching NRS (mean group difference after 3 months: -0.7 (95% confidence interval [CI], -1.1 to -0.4; p = 0.001); Skindex-29 overall (mean group difference after 3 months: 3.2 [95% CI, -0.6 to 7.0; p = 0.009]); Skindex-29 degree of symptoms (mean group difference after 3 months: 0.9 [95% CI, -0.2 to 1.9; p = 0.007]); and Skindex-29 psychological functioning (mean group difference after 3 months: 1.7 [95% CI, 0-3.4; p = 0.002]). CONCLUSION: Results were negative on the primary outcome; however, secondary outcomes included some statistically significant results favoring IHMs against placebo after 3 months. TRIAL REGISTRATION: CTRI/2019/11/021999; UTN: U1111-1242-0070.
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Homeopatia , Materia Medica , Tinha , Humanos , Homeopatia/métodos , Método Duplo-Cego , Tinha/tratamento farmacológico , Materia Medica/uso terapêutico , Prurido/tratamento farmacológico , Resultado do TratamentoRESUMO
Stable and efficient hydrocarbon degrading microbial consortia were developed from a refinery sludge through nitrate amendment for their application in enhanced bioremediation of petroleum contaminated waste. Nitrate induced biostimulation of refinery sludge resulted in increased abundance of hydrocarbon degrading Rhodocyclaceae, Xanthomonadaceae, Syntrophaceae and Comamonadaceae members. Repeated subculturing of nitrate stimulated communities in crude oil supplemented basal medium was done under aerobic and anaerobic conditions. Aerobically enriched consortia (composed of Pseudomonadaceae, Pseudoxanthomonadaceae and unclassified Comamonadaceae) showed their ability to utilize alkanes, aromatics and crude oil as growth substrates. Anaerobically enriched consortium was predominated by Bacillaceae, Pseudomonadaceae, Xanthomonadaceae, Porphyromonadaceae and Comamonadaceae members. Anaerobic consortium was found to be relatively less efficient in terms of TPH (total petroleum hydrocarbons) degradation compared to its aerobic counterpart. These enriched microbial consortia were finally tested for their biodegradation performance and stability during bioremediation of highly contaminated refinery sludge using different strategies. A 30 days microcosm based bioremediation trial showed that bioaugmentation of aerobic cultures with refinery sludge was more effective in TPH degradation (~ 65% degradation) compared to the anaerobic consortium (only 36% TPH degradation) and a combination of bioaugmentation and nitrate amendment with sludge resulted in enhanced hydrocarbon attenuation (up to 86% TPH degradation). Subsequent community analysis at the end of bioremediation trial confirmed the stability of the added microbial populations. Thus, the strategy of bioaugmentation of specially enriched native microbial populations in combination with nitrate amendment was successfully used for the enhanced bioremediation of petroleum hydrocarbon contaminated refinery waste.
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Bactérias/classificação , Hidrocarbonetos/química , Nitratos/metabolismo , Petróleo/metabolismo , Esgotos/microbiologia , Aerobiose , Anaerobiose , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Biodegradação Ambiental , DNA Bacteriano/genética , DNA Ribossômico/genética , Consórcios Microbianos , Filogenia , RNA Ribossômico 16S/genética , Esgotos/químicaRESUMO
BACKGROUND: Sustainable management of voluminous and hazardous oily sludge produced by petroleum refineries remains a challenging problem worldwide. Characterization of microbial communities of petroleum contaminated sites has been considered as the essential prerequisite for implementation of suitable bioremediation strategies. Three petroleum refinery sludge samples from North Eastern India were analyzed using next-generation sequencing technology to explore the diversity and functional potential of inhabitant microorganisms and scope for their on-site bioremediation. RESULTS: All sludge samples were hydrocarbon rich, anaerobic and reduced with sulfate as major anion and several heavy metals. High throughput sequencing of V3-16S rRNA genes from sludge metagenomes revealed dominance of strictly anaerobic, fermentative, thermophilic, sulfate-reducing bacteria affiliated to Coprothermobacter, Fervidobacterium, Treponema, Syntrophus, Thermodesulfovibrio, Anaerolinea, Syntrophobacter, Anaerostipes, Anaerobaculum, etc., which have been well known for hydrocarbon degradation. Relatively higher proportions of archaea were detected by qPCR. Archaeal 16S rRNA gene sequences showed presence of methanogenic Methanobacterium, Methanosaeta, Thermoplasmatales, etc. Detection of known hydrocarbon utilizing aerobic/facultative anaerobic (Mycobacterium, Pseudomonas, Longilinea, Geobacter, etc.), nitrate reducing (Gordonia, Novosphigobium, etc.) and nitrogen fixing (Azovibrio, Rhodobacter, etc.) bacteria suggested niche specific guilds with aerobic, facultative anaerobic and strict anaerobic populations. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) predicted putative genetic repertoire of sludge microbiomes and their potential for hydrocarbon degradation; lipid-, nitrogen-, sulfur- and methane- metabolism. Methyl coenzyme M reductase A (mcrA) and dissimilatory sulfite reductase beta-subunit (dsrB) genes phylogeny confirmed methanogenic and sulfate-reducing activities within sludge environment endowed by hydrogenotrophic methanogens and sulfate-reducing Deltaproteobacteria and Firmicutes members. CONCLUSION: Refinery sludge microbiomes were comprised of hydrocarbon degrading, fermentative, sulfate-reducing, syntrophic, nitrogen fixing and methanogenic microorganisms, which were in accordance with the prevailing physicochemical nature of the samples. Analysis of functional biomarker genes ascertained the activities of methanogenic and sulfate-reducing organisms within sludge environment. Overall data provided better insights on microbial diversity and activity in oil contaminated environment, which could be exploited suitably for in situ bioremediation of refinery sludge.
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Bactérias Anaeróbias/classificação , Hidrocarbonetos/metabolismo , Metano/biossíntese , Petróleo/metabolismo , Esgotos/microbiologia , Bactérias Redutoras de Enxofre/classificação , Archaea/classificação , Archaea/isolamento & purificação , Bactérias Anaeróbias/isolamento & purificação , Biodegradação Ambiental , Fermentação , Índia , Consórcios Microbianos , Petróleo/microbiologia , Filogenia , RNA Ribossômico 16S/genética , Bactérias Redutoras de Enxofre/isolamento & purificaçãoRESUMO
Morphology switching by an external stimulus creates the possibility to detect and control the activity and functionality of bio-molecules. Unconjugated bilirubin (UCB), a waste product resulting from heme catabolism, is highly sensitive towards blue light induced configurational conversion from (4Z,15Z) to (4Z,15E)-bilirubin. UCB has a distinct elongated nanostructure which is readily photoswitchable to spherical by external blue light (470 nm) irradiation. Herein, the morphology alteration by blue light was nicely correlated with the photoisomerisation of UCB, using different microscopic and spectroscopic techniques. To restrict the other photo-incidents during phototreatment on UCB, a suitable time frame was calibrated by monitoring the absorption, HPLC, lifetime distribution and 1H NMR studies. Furthermore, by the help of this morphological transition as a marker, UCB early stage photoisomerisation has also been triggered by two-photon irradiation (940 nm).
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Bilirrubina/química , Luz , Processos Fotoquímicos , Isomerismo , Modelos Moleculares , Conformação MolecularRESUMO
Franconibacter pulveris strain DJ34, isolated from Duliajan oil fields, Assam, was characterized in terms of its taxonomic, metabolic and genomic properties. The bacterium showed utilization of diverse petroleum hydrocarbons and electron acceptors, metal resistance, and biosurfactant production. The genome (4,856,096bp) of this strain contained different genes related to the degradation of various petroleum hydrocarbons, metal transport and resistance, dissimilatory nitrate, nitrite and sulfite reduction, chemotaxy, biosurfactant synthesis, etc. Genomic comparison with other Franconibacter spp. revealed higher abundance of genes for cell motility, lipid transport and metabolism, transcription and translation in DJ34 genome. Detailed COG analysis provides deeper insights into the genomic potential of this organism for degradation and survival in oil-contaminated complex habitat. This is the first report on ecophysiology and genomic inventory of Franconibacter sp. inhabiting crude oil rich environment, which might be useful for designing the strategy for bioremediation of oil contaminated environment.
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Enterobacteriaceae/crescimento & desenvolvimento , Genoma Bacteriano , Hidrocarbonetos/metabolismo , Petróleo/microbiologia , Composição de Bases , Biodegradação Ambiental , Enterobacteriaceae/classificação , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Tamanho do Genoma , Filogenia , Análise de Sequência de DNARESUMO
A newly designed and structurally characterized cell permeable diformyl-p-cresol based receptor (HL) selectively senses the AsO3(3-) ion up to ca. 4.1 ppb in aqueous media over the other competitive ions at biological pH through an intermolecular H-bonding induced CHEF (chelation-enhanced fluorescence) process, established by detailed experimental and theoretical studies. This biofriendly probe is highly competent in recognizing the existence of AsO3(3-) ions in a living organism by developing an image under a fluorescence microscope and useful to estimate the amount of arsenite ions in various water samples.
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Arsenitos/análise , Quelantes/química , Cresóis/química , Corantes Fluorescentes/química , Água/química , Quelantes/síntese química , Cresóis/síntese química , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Íons/análise , Microscopia de Fluorescência , Estrutura Molecular , Teoria QuânticaRESUMO
A newly synthesized and crystalographically characterized napthelenepyrazol conjugate, 1-[(5-phenyl-1H-pyrazole-3-ylimino)-methyl]-naphthalen-2-ol (HL) behaves as an Al(III) ion-selective chemosensor through internal charge transfer (ICT)-chelation-enhanced fluorescence (CHEF) processes in 100 mM HEPES buffer (waterDMSO 5:1, v/v) at biological pH with almost no interference of other competitive ions. This mechanism is readily studied from electronic, fluorimetric and (1)H NMR titration. The probe (HL) behaved as a highly selective fluorescent sensor for Al(III) ions as low as 31.78 nM within a very short response time (1520 s). The sensor (HL), which has no cytotoxicity, is also efficient in detecting the distribution of Al(III) ions in HeLa cells via image development under fluorescence microscope.
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Alumínio/química , Biomarcadores/análise , Complexos de Coordenação/química , Naftóis/química , Pirazóis/química , Espectrometria de Fluorescência , Quelantes/química , Técnicas de Química Analítica , Complexos de Coordenação/síntese química , Complexos de Coordenação/metabolismo , Cristalografia por Raios X , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Células HeLa , Humanos , Íons/química , Microscopia Confocal , Conformação Molecular , Naftóis/síntese química , Pirazóis/síntese química , Água/químicaRESUMO
The effect of substituents on FRET in two newly designed rhodamine-based Hg(2+) ion selective chemosensors (L¹ and L²) has been explored by a systematic experimental and theoretical study. Comparison of these sensors in the analytical study and imaging of Hg(2+) ions in living cells has also been included.
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Benzaldeídos/química , Transferência Ressonante de Energia de Fluorescência/métodos , Corantes Fluorescentes/química , Hidrazinas/química , Mercúrio/análise , Rodaminas/química , Cátions Bivalentes , Estrutura MolecularRESUMO
Oxidative depolymerization of an industrial lignin was performed to study the effect of various metal oxides in oxygen and air atmosphere. CeO2 exhibited excellent catalytic property, and promoted the production of bio-oil yield up to a maximum of 49 wt% in 10 bar O2, whereas 31 wt% bio-oil was noticed in atmospheric air. GC-MS analysis of bio-oil showed that high selectivity towards acetosyringone was observed in the presence of air (70.5 area%) as compared to oxygen (48.1 area%). Herein, we have also applied transitional metals (Co, Mn and Cu) doped CeO2 catalysts. Compared to Cu and Mn, Co metal showed efficient activity that promoted the breaking of labile ß-O-4 linkages via the conversion of Cα-OH in to carbonyl group in atmospheric air resulting in the formation of acetosyringone up to 78 area%. Moreover, it exhibited excellent catalytic activity up to four successive cycles. Catalyst has been characterized by XRD, BET, TEM, FT-IR and Raman spectroscopy.
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Lignina , Óxidos , Catálise , Lignina/química , Estresse Oxidativo , Óxidos/química , Oxigênio , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Microbial activities within oil reservoirs have adversely impacted the world's majority of oil by lowering its quality, thereby increasing its recovery and refining cost. Moreover, conventional method of extraction leaves behind nearly two-thirds of the fossil fuels in the oil fields. This huge potential can be extracted if engineered methanogenic consortium is adapted to convert the hydrocarbons into natural gas. This process involves conversion of crude oil hydrocarbons into methanogenic substrates by syntrophic and fermentative bacteria, which are subsequently utilized by methanogens to produce methane. Microbial diversity of such environments supports the viability of this process. This review illuminates the potentials of abundant microbial groups such as Syntrophaceae, Anaerolineaceae, Clostridiales and Euryarchaeota in petroleum hydrocarbon-related environment, their genetic markers, biochemical process and omics-based bioengineering methods involved in methane generation. Increase in the copy numbers of catabolic genes during methanogenesis highlights the prospect of developing engineered biofuel recovery technology. Several lab-based methanogenic consortia from depleted petroleum reservoirs and microcosm studies so far would not be enough for field application without the advent of multi-omics-based technologies to trawl out the bottleneck parameters of the enhanced fuel recovery process. The adaptability of efficient consortium of versatile hydrocarbonoclastic and methanogenic microorganisms under environmental stress conditions is further needed to be investigated. The improved process might hold the potential of methane extraction from petroleum waste like oil tank and refinery sludge, oil field deposits, etc. What sounds as biodegradation could be a beginning of converting waste into wealth by recovery of stranded energy assets.
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Euryarchaeota , Petróleo , Biodegradação Ambiental , Biocombustíveis , Marcadores Genéticos , Hidrocarbonetos , MetanoRESUMO
BACKGROUND: Arsenite oxidase (EC 1.20.2.1) is a metalloenzyme that catalyzes the oxidation of arsenite into lesser toxic arsenate. In this study, 78 amino acid sequences of arsenite oxidase from unculturable bacteria available in metagenomic data of arsenic-contaminated soil have been characterized by using standard bioinformatics tools to investigate its phylogenetic relationships, three-dimensional structure and functional parameters. RESULTS: The phylogenetic relationship of all arsenite oxidase from unculturable microorganisms was revealed their closeness to bacterial order Rhizobiales. The higher aliphatic content showed that these enzymes are thermostable and could be used for in situ bioremediation. A representative protein from each phylogenetic cluster was analysed for secondary structure arrangements which indicated the presence of α-helices (~63%), ß-sheets (57-60%) and turns (13-15%). The validated 3D models suggested that these proteins are hetero-dimeric with two chains whereas alpha chain is the main catalytic subunit which binds with arsenic oxides. Three representative protein models were deposited in Protein Model Database. The query enzymes were predicted with two conserved motifs, one is Rieske 3Fe-4S and the other is molybdopterin protein. CONCLUSIONS: Computational analysis of protein interactome revealed the protein partners might be involved in the whole process of arsenic detoxification by Rhizobiales. The overall report is unique to the best of our knowledge, and the importance of this study is to understand the theoretical aspects of the structure and functions of arsenite oxidase in unculturable bacteria residing in arsenic-contaminated sites.
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Microbial community analysis of crude oil containing sludge collected from Duliajan oil field, Assam, India, showed the predominance of hydrocarbon-degrading bacteria such as Pseudomonas (20.1%), Pseudoxanthomonas (15.8%), Brevundimonas (1.6%), and Bacillus (0.8%) alongwith anaerobic, fermentative, nitrogen-fixing, nitrate-, sulfate-, and metal-reducing, syntrophic bacteria, and methanogenic archaea. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analysis indicated gene collection for potential hydrocarbon degradation, lipid, nitrogen, sulfur, and methane metabolism. The culturable microbial community was predominated by Pseudomonas and Bacillus with the metabolic potential for utilizing diverse hydrocarbons, crude oil, and actual petroleum sludge as sole carbon source during growth and tolerating various environmental stresses prevailing in such contaminated sites. More than 90% of the isolated strains could produce biosurfactant and exhibit catechol 2,3-dioxygenase activity. Nearly 30% of the isolates showed alkane hydroxylase activity with the maximum specific activity of 0.54 µmol min-1 mg-1. The study provided better insights into the microbial diversity and functional potential within the crude oil containing sludge which could be exploited for in situ bioremediation of contaminated sites.
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Microbiota , Petróleo , Biodegradação Ambiental , Hidrocarbonetos , Campos de Petróleo e Gás , Petróleo/análise , Filogenia , EsgotosRESUMO
Alkane-1-monooxygenase of alkanotrophic Rhodococcus species has been characterized using standard bioinformatics tools to investigate phylogenetic relationships, and three-dimensional structure and functions. Results revealed that activity of the Rhodococcus alkane-1-monooxygenase would be optimum in alkaline pH as their isoelectric points were in the range of 7.5 to 9. Higher aliphatic index (87 to 95) indicated that these enzymes are thermostable. Extinction coefficient of the enzyme varied from 68,793 to 1,25,820 M-1 cm-1 and average molecular weight was 45 kDa. Secondary structures predicted maximum alpha-helical content rather than the other conformations such as sheets or turns. The instability index (II) of most stable query protein was 39.7% which was lowest among all 76 proteins analysed in this study. Predicted 3D structure of query protein revealed that it contains homodimer polypeptides. The suitable template for query protein was Flavin-dependent luciferase-type alkane monooxygenase. The presence of 98.3% amino acid residues in Ramachandran plot was determined in 3-D protein model which confirmed the model feasibility. The predicted model contains 12% more α-helix than template protein which indicated towards membrane localization of the protein. The protein interactome partners of predicted model were determined as FMN-dependent oxidoreductase, molybdopterin, nuclear transport factor, and peroxiredoxin. The predicted tertiary model of R. rhodochrous alkane-1-monooxygenase (OOL33526.1) was deposited in Protein Model Database (Accession No.: PM0083166). The overall report is unique to best of our knowledge, and the importance of this study is to understand the theoretical aspects of structure and functions of alkane-1-monooxygenase of hydrocarbonoclastic strains of Rhodococcus.
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Amyloid polymorphism has emerged as an important topic of research in recent years to identify the particular species responsible for several neurodegenerative disorders, whereas the concept is overlooked in the case of the simplest building block, that is, l-phenylalanine (l-Phe) self-assembly. Here, we report the first evidence of l-Phe polymorphism and the conversion of metastable helical fibrillar to thermodynamically stable rodlike crystalline morphologies with increasing time and temperature. Furthermore, only the fibrillar l-Phe polymorph shows a significant modulation of the model membrane. In addition, the l-Phe molecules prefer to arrange in a multilayered rodlike fashion than in a lateral arrangement, which reduces the membrane binding ability of the l-Phe polymorph due to the decrease in the partial charge of the N-terminal of l-Phe units. The present work exemplifies a different approach to understanding l-Phe self-assembly and provides an effective strategy for the therapy of phenylketonuria by scrutinizing the discrete membrane activity of different l-Phe polymorphs.
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Amiloide/química , Fenilalanina/química , Fenilcetonúrias/metabolismo , Fatores Etários , Cristalização , Humanos , Ligação de Hidrogênio , Imagem Óptica , Ligação Proteica , Conformação Proteica , Dobramento de Proteína , Multimerização Proteica , Temperatura , TermodinâmicaRESUMO
Infusions of Indian black tea (BTI), when administered orally, produced significant inhibition of rat paw oedema, induced with carrageenin (pre and post treatment) and arachidonic acid. BTI was also found to inhibit peritoneal capillary permeability and caused a marked reduction of lipopolysaccharide induced PGE(2) generation. In these models, the observed antioedema effect was similar to that of BW755C (a dual inhibitor of cyclooxygenase and 5-lipoxygenase enzymes). BTI was found to scavenge superoxide and hydroxyl radicals, and also protected rat erythrocytes from the damaging effects of hydrogen peroxide. In chronic studies, BTI inhibited granuloma formation along with the reduction of both lipid peroxidation and hydroxyproline content (in the granuloma tissue). Significant antiarthritic activity was observed with regular administration of BTI in the Freund's adjuvant induced model of arthritis. Chronic treatment with BTI (in arthritic rats) resulted in a decrease of paw diameter and tissue lipid peroxidation, along with a restoration of GSH, catalase and superoxide dismutase levels.
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Inflamação/tratamento farmacológico , Extratos Vegetais/farmacologia , Folhas de Planta/química , Chá/química , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Ácido Acético , Doença Aguda , Animais , Ácido Araquidônico , Artrite Experimental/tratamento farmacológico , Artrite Experimental/imunologia , Doença Crônica , Edema/induzido quimicamente , Edema/tratamento farmacológico , Inflamação/induzido quimicamente , Lipopolissacarídeos/farmacologia , Masculino , Extratos Vegetais/química , RatosRESUMO
Model lipid vesicles self-reproduce to generate unilamellar daughter vesicles in the presence of a cell-penetrating peptide. Fluorescence lifetime and anisotropy image analysis exquisitely capture the change in the lipid bilayer rigidity throughout the process, whereas a solvation dynamic study delineates the change in the dynamics of the encapsulated water inside the vesicles. Overall, our results provide an experimental underpinning of the role of the lipid bilayer structural changes in self-reproduction, which can exhibit great potential for interpreting the protein-membrane interaction in the emergence of life and for developing new therapeutic strategies.
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Peptídeos Penetradores de Células/química , Bicamadas Lipídicas/química , Fosfatidilcolinas/química , Lipossomas Unilamelares/química , Fluorescência , Corantes Fluorescentes/química , Microscopia de Fluorescência , Piranos/química , Espectrometria de Fluorescência , Estirenos/química , Água/químicaRESUMO
Studying the self-assembly of uracil derivatives has great importance in biochemistry and nanotechnology. Now, in order to architect unique and interesting nucleobase nanostructures, herein, we report a simple, yet robust uracil moiety based platform which is potentially capable to self-assemble into fibrils. The system is validated using eight uracil moiety derivatives and the effect is examined via fluorescence lifetime imaging microscopy (FLIM), field emission scanning electron microscopy (FESEM), steady state DCM fluorescence and fluorescence correlation spectroscopy (FCS). FLIM and FESEM give qualitative information regarding the fibril formation of different morphologies including string, rod, flower, needles etc. Steady state DCM fluorescence and FCS establish a quantitative estimation of the extent of fibril formation. The involvement of hydrogen bonding interaction between NH and CO groups in the fibrillar growth of 5-IU is evoked from the crystallographic study. Again, the key role of different functional groups behind the formation of fibrillar network is investigated through blocking the COO- group of orotic acid with lanthanides. Finally, esterification and N,N'-dimethylation exquisitely explore the role and priority of different groups in the fibril formation of pyrimidine analogues. The results may be useful for understanding the processes of self-assembly of the uracil derivatives and the rationalized design of the uracil based supramolecular structures with specific properties.
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Scope for developing an engineered bioremediation strategy for the treatment of hydrocarbon-rich petroleum refinery waste was investigated through biostimulation and bioaugmentation approaches. Enhanced (46-55%) total petroleum hydrocarbon (TPH) attenuation was achieved through phosphate, nitrate or nitrate+phosphate amendment in the sludge with increased (upto 12%) abundance of fermentative, hydrocarbon degrading, sulfate-reducing, CO2-assimilating and methanogenic microorganisms (Bacillus, Coprothermobacter, Rhodobacter, Pseudomonas, Achromobacter, Desulfitobacter, Desulfosporosinus, T78, Methanobacterium, Methanosaeta, etc). Together with nutrients, bioaugmentation with biosurfactant producing and hydrocarbon utilizing indigenous Bacillus strains resulted in 57-75% TPH reduction. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analysis revealed enhanced gene allocation for transporters (0.45-3.07%), ABC transporters (0.38-2.07%), methane (0.16-1.06%), fatty acid (0.018-0.15%), nitrogen (0.07-0.17%), butanoate (0.06-0.35%), propanoate (0.004-0.26%) metabolism and some xenobiotics (0.007-0.13%) degradation. This study indicated that nutrient-induced community dynamics of native microorganisms and their metabolic interplay within oil refinery sludge could be a driving force behind accelerated bioremediation.
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Biodegradação Ambiental , Esgotos , Poluentes do Solo , Hidrocarbonetos , Petróleo , Filogenia , Microbiologia do SoloRESUMO
Intrinsic biodegradation potential of bacteria from petroleum refinery waste was investigated through isolation of cultivable strains and their characterization. Pseudomonas and Bacillus spp. populated the normal cultivable taxa while prolonged enrichment with hydrocarbons and crude oil yielded hydrocarbonoclastic bacteria of genera Burkholderia, Enterobacter, Kocuria, Pandoraea, etc. Strains isolated through enrichment showed assemblages of superior metabolic properties: utilization of aliphatic (C6-C22) and polyaromatic compounds, anaerobic growth with multiple terminal electron acceptors and higher biosurfactant production. Biodegradation of dodecane was studied thoroughly by GC-MS along with detection of gene encoding alkane hydroxylase (alkB). Microcosms bioaugmented with Enterobacter, Pandoraea and Burkholderia strains showed efficient biodegradation (98% TPH removal) well fitted in first order kinetic model with low rate constants and decreased half-life. This study proves that catabolically efficient bacteria resides naturally in complex petroleum refinery wastes and those can be useful for bioaugmentation based bioremediation.
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Biodegradação Ambiental , Hidrocarbonetos , Petróleo , Bactérias , Poluentes do SoloRESUMO
A new ion-exchanger having chemical formula [Me2NH2]3[Mo12O40S] and belonging to the class of Keggin type polyoxometalate was synthesized and characterized by single-crystal X-ray structure determination. The crystal of the exchanger is rhombohedral, space group R-3 with cell dimensions, a =16.504(18) Å, b =16.504(18)Å (1) Å, c =25.23(3)Å and α=90.00°, ß=90.00°, γ=120.00° and Z =6, 3.284gcm-3. The compound behaves as an ion-exchanger and it is significantly stable towards thermal, chemical environments and total radiation dose of 35.0kGy. Radiochemical separation of the short-lived daughter carrier-free 9°Y (T1/2 =64.08h) from its long-lived parent 90Sr (T1/2 =29 a) using this material at pH 6.0 with 1.0% EDTA solution as an eluent.