Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 65
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Environ Manage ; 360: 121182, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38772237

RESUMO

The emergence of algal biorefineries has garnered considerable attention to researchers owing to their potential to ensure carbon neutrality via mitigation of atmospheric greenhouse gases. Algae-derived biofuels, characterized by their carbon-neutral nature, stand poised to play a pivotal role in advancing sustainable development initiatives aimed at enhancing environmental and societal well-being. In this context, algae-based wastewater treatment systems are greatly appreciated for their efficacy in nutrient removal and simultaneous bioenergy generation. These systems leverage the growth of algae species on wastewater nutrients-including carbon, nitrogen, and phosphorus-alongside carbon dioxide, thus facilitating a multifaceted approach to pollution remediation. This review seeks to delve into the realization of carbon neutrality through algae-mediated wastewater treatment approaches. Through a comprehensive analysis, this review scrutinizes the trajectory of algae-based wastewater treatment via bibliometric analysis. It subsequently examines the case studies and empirical insights pertaining to algae cultivation, treatment performance analysis, cost and life cycle analyses, and the implementation of optimization methodologies rooted in artificial intelligence and machine learning algorithms for algae-based wastewater treatment systems. By synthesizing these diverse perspectives, this study aims to offer valuable insights for the development of future engineering applications predicated on an in-depth understanding of carbon neutrality within the framework of circular economy paradigms.


Assuntos
Carbono , Purificação da Água , Biocombustíveis , Dióxido de Carbono/análise , Nitrogênio , Fósforo , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , Purificação da Água/métodos
2.
Proteins ; 91(2): 268-276, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36121161

RESUMO

Cationic helical peptides play a crucial role in applications such as anti-microbial and anticancer activity. The activity of these peptides directly correlates with their helicity. In this study, we have performed extensive all-atom molecular dynamics simulations of 25 Lysine-Leucine co-polypeptide sequences of varying charge density ( λ ) and patterns. Our findings showed that, an increase in the charge density on the peptide leads to a gradual decrease in the helicity up to a critical charge density λ c . Beyond λ c , a complete helix to coil transition was observed. The decrease in the helicity is correlated with the increased number of water molecules in first solvation shell, solvent-exposed surface area, and a higher value of the radius of gyration of the peptide.


Assuntos
Simulação de Dinâmica Molecular , Peptídeos , Estrutura Secundária de Proteína , Peptídeos/química , Solventes/química , Água/química , Dicroísmo Circular
3.
J Chem Inf Model ; 63(16): 5375-5383, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-37581491

RESUMO

The prediction of disordered regions in proteins is crucial for understanding their functions, dynamics, and interactions. Intrinsically disordered proteins (IDPs) play a key role in many biological processes like cell signaling, recognition, and regulation, but experimentally determining these regions can be challenging due to their high mobility. To address this challenge, we present an algorithm called HydroDisPred (HDP). HDP uses a single parameter, the fraction of hydrophobicity (λ) in each segment of the protein, to accurately predict disordered regions. The algorithm was validated using experimental data from the DisProt database and was found to be on par and, in some cases, more effective than the existing algorithms. HDP is a simple and effective method for identifying disordered regions in proteins, and its prediction is not affected by the availability of training data, unlike other ML approaches. The application is housed in the web server and can be accessed through the URL https://proseqanalyser.iitgn.ac.in/hydrodispred/.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Proteínas/química , Algoritmos
4.
Environ Res ; 237(Pt 2): 117100, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37689336

RESUMO

The levels of pesticides in air, water, and soil are gradually increasing due to its inappropriate management. In particular, agricultural runoff inflicts the damages on the ecosystem and human health at massive scale. Present study summarizes 70 studies in which investigations on removal or treatment of pesticides/insecticides/herbicides are reported. A bibliometric analysis was also done to understand the recent research trends through the analysis of 2218 publications. The specific objectives of this study are as follows: i) to inventorize the characteristics details of agriculture runoff and analyzing the occurrence and impacts of pesticides, ii) analyzing the role and interaction of pesticides in different environmental segments, iii) investigating the fate of pesticides in agriculture runoff treatment systems, iv) summarizing the experiences and findings of most commonly technology deployed for pesticides remediation in agriculture runoff including target pesticide(s), specifications, configuration of technological intervention. Among the reported technologies for pesticide treatment in agriculture runoff, constructed wetland was at the top followed by algal or photobioreactor. Among various advanced oxidation processes, photo Fenton method is mainly used for pesticides remediation such as triazine, methyl parathion, fenuron and diuron. Algal bioreactors are extensively used for a wide range of pesticides treatment including 2,4-Dichlorophenoxyacetic acid, 2-methyl-4-chlorophenoxyacetic acid, alachlor, diuron, chlorpyrifos, endosulfan, and imidacloprid; especially at lower hydraulic retention time of 2-6 h. This study highlights that hybrid approaches can offers potential opportunities for effective removal of pesticides in a more viable manner.

5.
Sensors (Basel) ; 23(23)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38067772

RESUMO

This paper aims to enhance the capacitance of electroactive polymer (EAP)-based strain sensors. The enhancement in capacitance was achieved by using a free-standing stretchable polymer film while introducing conducting polymer to fabricate a hybrid dielectric film with controlled conductivity. In this work, styrene-ethylene-butylene-styrene (SEBS) rubber was used as the base material, and dodecyl benzene sulfonate anion (DBSA)-doped polyaniline (PANI) was used as filler to fabricate a hybrid composite conducting film. The maleic anhydride group of the SEBS Rubber and DBSA, the anion of the polyaniline dopant, make a very stable dispersion in Toluene and form a free-standing stretchable film by solution casting. DBSA-doped polyaniline increased the conductivity and dielectric constant of the dielectric film, resulting in a significant enhancement in the capacitance of the EAP-based strain sensor. The sensor presented in this article exhibits capacitance values ranging from 24.7 to 100 µF for strain levels ranging from 0 to 100%, and sensitivity was measured 3 at 100% strain level.

6.
Phys Chem Chem Phys ; 23(22): 12620-12629, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34075973

RESUMO

Protein folding is a very complex process and, so far, the mechanism of folding still intrigues the research community. Despite a large conformational space available (O(1047) for a 100 amino acid residue), most proteins fold into their native state within a very short time. While small proteins fold relatively fast (a few microseconds) large globular proteins may take as long as several milliseconds to fold. During the folding process, the protein synthesized in the ribosome is exposed to the crowded environment of the cell and is easily prone to misfolding and aggregation due to interactions with other proteins or biomacromolecules present within the cell. These large proteins, therefore, rely on chaperones for their folding and repair. Chaperones are known to have hydrophobic patchy domains that play a crucial role in shielding the protein against misfolding and disaggregation of aggregated proteins. In the current article, Monte Carlo simulations carried out in the framework of the hydrophobic-polar (H-P) lattice model indicate that hydrophobic patchy domains drastically reduce the inter-protein interactions and are efficient in disaggregating proteins. The effectiveness of the disaggregation depends on the size and distribution of these patches on the surface and also on the strength of the interaction between the protein and the surface. Further, our results indicate that when the patch is complementary to the exposed hydrophobic patch of the protein, protein disaggregation is accompanied by stabilization of the protein even relative to its bulk behavior due to favorable protein-surface interactions. We believe that these findings shed light on the role of the class of chaperones known as heat shock proteins (Hsps) on protein disaggregation and refolding.


Assuntos
Proteínas de Choque Térmico/química , Chaperonas Moleculares/química , Simulação de Dinâmica Molecular , Interações Hidrofóbicas e Hidrofílicas , Método de Monte Carlo , Dobramento de Proteína
7.
Environ Dev Sustain ; 23(8): 12006-12023, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33519297

RESUMO

COVID-19 has affected the global economy like no other crisis in the history of mankind. It forced worldwide lockdown and economic shutdown to the point from where the recovery process has been very difficult. It has affected demand, supply, production and consumption in such a way that the entire economic development cycle has gone to its lowest levels. COVID-19 has also affected the social and economic sustainability structure which has led from one crisis to another and the developing countries have been the worst hit. Economic crisis resulted in unemployment leading to labour migrations, inevitable casualties and rising poverty etc. However, at a certain level, a few industries and organizations have shown resilience with better anticipation and survivability which may lead them to a quicker recovery. The current study aims at presenting a holistic view of organizational resilience which leads to the overall sustainable development. The study considers three aspects of organizational resilience as crisis anticipation, organizational robustness and recoverability. It assesses the impact of the aspects of resilience on social sustainability and economic sustainability. The study uses empirical analysis of primary data which is analysed to verify the hypothesized relationships by using a structural equation modelling approach. The study finds out that predicting the crisis and disruptions, building robustness and recoverability have a positive effect on both the social and economic aspects of sustainability. Findings of the study have their practical implications for industry, researchers and society.

8.
Appl Microbiol Biotechnol ; 103(16): 6851-6852, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31302709

RESUMO

In our original published manuscript entitled "Metagenome to phenome approach enables isolation and genomics characterization of Kalamiella piersonii gen. nov., sp. nov. from the International Space Station" (Singh et al. 2019), we found a taxonomic description format error: As per the Rule 27.

9.
Appl Microbiol Biotechnol ; 103(11): 4483-4497, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31011775

RESUMO

Several evolutionarily distinct, near full-length draft metagenome-resolved genomes (MRG), were assembled from sequences recovered from the International Space Station (ISS) environments. The retrieval of MRGs facilitated the exploration of a large collection of archived strains (~ 500 isolates) and assisted in isolating seven related strains. The whole genome sequences (WGS) of seven ISS strains exhibited 100% identity to the 4.85 × 106 bp of four MRGs. The "metagenome to phenome" approach led to the description of a novel bacterial genus from the ISS samples. The phylogenomics and traditional taxonomic approaches suggested that these seven ISS strains and four MRGs were not phylogenetically affiliated to any validly described genera of the family Erwiniaceae, but belong to a novel genus with the proposed name Kalamiella. Comparative genomic analyses of Kalamiella piersonii strains and MRGs showed genes associated with carbohydrate (348 genes), amino acid (384), RNA (59), and protein (214) metabolisms; membrane transport systems (108), pathways for biosynthesis of cofactors, vitamins, prosthetic groups, and pigments (179); as well as mechanisms for virulence, disease, and defense (50). Even though Kalamiella genome annotation and disc diffusion tests revealed multidrug resistance, the PathogenFinder algorithm predicted that K. piersonii strains are not human pathogens. This approach to isolating microbes allows for the characterization of functional pathways and their potential virulence properties that can directly affect human health. The isolation of novel strains from the ISS has broad applications in microbiology, not only because of concern for astronaut health but it might have a great potential for biotechnological relevance. The metagenome to phenome approach will help to improve our understanding of complex metabolic networks that control fundamental life processes under microgravity and in deep space.


Assuntos
Microbiologia Ambiental , Gammaproteobacteria/classificação , Gammaproteobacteria/isolamento & purificação , Filogenia , Astronave , Técnicas de Tipagem Bacteriana , Gammaproteobacteria/genética , Gammaproteobacteria/metabolismo , Humanos , Metagenômica , Sequenciamento Completo do Genoma
10.
Int J Environ Health Res ; 28(4): 419-431, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29889552

RESUMO

Present study reports the characterization results of settled dust particles in different indoor micro-environments of an academic institution in India. Field emission scanning electron microscope analysis of indoor dust revealed the presence of mineral particles, fly ash, and soot particles of different morphologies. Energy-dispersive X-ray spectroscopy analysis of indoor dust indicated that crystal particles are comprised of elements such as C, O, Na, Mg, Al, Si, S, Cl, K, Ca, Fe, and Ti. These elements accounted for more than 99% of the samples. The average content of O (42.7%) and C (18.9%) in the dust particles was found to be higher than their natural abundances. The concentrations of PM10, PM2.5, and PM1 were observed in the range of 88-58, 37-33, 23-29 µg/m3, respectively. Except temperature, other parameters such as volatile organic carbon, carbon dioxide concentration, and relative humidity were found to be within comfort limits of American Society of Heating, Refrigerating, and Air-Conditioning Engineers. ABBREVIATIONS: ASHRAE: American Society of Heating, Refrigerating, and Air-Conditioning Engineers; CO2: carbon dioxide; COPD: chronic obstructive pulmonary disease; EDX: energy-dispersive X-ray; FESEM: field emission scanning electron microscope; FTIR: Fourier transform infrared spectroscopy; IAP: indoor air pollution; IAQ: indoor air quality; HAP: household air pollution; OAP: outdoor air pollution; PM: particulate matter; VOC: volatile organic carbon; WHO: World Health Organization.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Poeira/análise , Carbono/análise , Dióxido de Carbono/análise , Monitoramento Ambiental , Umidade , Índia , Metais/análise , Instituições Acadêmicas , Compostos Orgânicos Voláteis/análise
11.
Int J Syst Evol Microbiol ; 67(1): 60-66, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27902248

RESUMO

The taxonomic position of a Gram-stain-positive, endospore-forming bacterium, strain KS16-9T, isolated from a marine sediment sample collected from Kovalam, Kanyakumari coastal region of the Indian Ocean, India, was analysed by a polyphasic approach. Strain KS16-9T had typical phenotypic characteristics and chemotaxonomic features (menaquinones, fatty acids and lipids) that were consistent with the genus Bacillus. omparative analysis of the 16S rRNA gene sequence of the strain with previously published Bacillus type strains confirmed that it belongs to the genus Bacillus and is moderately related to Bacillus persicus B48T (98.42 % similarity), followed by Bacillus foraminis CV53T (97.67 %) and Bacillus rigiliprofundi (97.61 %). Other species in the genus Bacillusshared <97.6 % 16S rRNA gene sequence similarity. Strain KS16-9T contained MK-7 as the predominant menaquinone, meso-diaminopimelic acid as the diagnostic cell-wall diamino acid, iso-C15 : 0 and anteiso-C15 : 0 as major fatty acids, and diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine as the major phospholipids. The DNA G+C content of strain KS16-9T was 45.4 mol%. Based on data from this polyphasic taxonomic study, strain KS16-9T represents a novel species of the genus Bacillus, for which the name Bacillus maritimus sp. nov. is proposed. The type strain is KS16-9T (=MTCC 12305T=DSM 100413T=KCTC 33834T).


Assuntos
Bacillus/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Bacillus/genética , Bacillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Índia , Oceano Índico , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
12.
Org Biomol Chem ; 15(48): 10212-10220, 2017 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-29177280

RESUMO

The intramolecular Morita-Baylis-Hillman reaction of ß-mono and ß,ß-disubstituted enones shows high yields and stereo-selective products when the reaction is performed in the presence of 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) as a solvent. In this work, we carried out a computational study using the density functional Becke 3-(B3) parameter exchange and the Lee-Yang-Parr (LYP) correlation functional and 6-31+G* basis set. Two major steps i.e. C-C bond formation and proton transfer were analysed using different pathways. The calculations show a very low barrier (ΔG† = 0.23 kcal mol-1) for C-C bond formation in the case of an experimentally dominant product. For this pathway the subsequent proton transfer via the HFIP step has a barrier of 26.98 kcal mol-1. The same has been confirmed using a Molecular Electrostatic Potential (MESP), which shows a negative region in between CC in the transition state. In spite of high barriers for proton transfer, the intermediate products formed in this reaction pathway are thermodynamically more stable in comparison with other pathways. The thermodynamic stability of the final product in this pathway is observed to surpass all other effects in the presence of HFIP, thereby corroborating the experimentally observed enantioselectivity.

13.
Water Sci Technol ; 75(10): 2246-2256, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28541932

RESUMO

In the present study, a life cycle assessment (LCA) approach was used to analyse the environmental impacts associated with the construction and operational phases of an integrated fixed-film activated sludge (IFAS) reactor treating municipal wastewater. This study was conducted within the boundaries of a research project that aimed to investigate the implementation related challenges of a package type IFAS reactor from an environmental perspective. Along with the LCA results of the construction phase, a comparison of the LCA results of seven operational phases is also presented in this study. The results showed that among all the inputs, the use of stainless steel in the construction phase caused the highest impact on environment, followed by electricity consumption in raw materials production. The impact of the construction phase on toxicity impact indicators was found to be significant compared to all operational phases. Among the seven operational phases of this study, the dissolved oxygen phase III, having a concentration of ∼4.5 mg/L, showed the highest impact on abiotic depletion, acidification, global warming, ozone layer depletion, human toxicity, fresh water eco-toxicity, marine aquatic eco-toxicity, terrestrial eco-toxicity, and photochemical oxidation. However, better effluent quality in this phase reduced the eutrophication load on environment.


Assuntos
Reatores Biológicos , Meio Ambiente , Esgotos , Eliminação de Resíduos Líquidos/métodos , Eutrofização , Aquecimento Global , Humanos , Águas Residuárias
14.
Artigo em Inglês | MEDLINE | ID: mdl-28095182

RESUMO

In the present study, the effect of three intermittent aeration (IA) cycles on treatment performance and microbial diversity was investigated in an integrated fixed film activated sludge (IFAS) reactor treating municipal wastewater. The results showed that IA strategies were able to achieve efficient removal of organics and nitrogen ranging between 90 and 95% and 70 and 80%, respectively, however the phosphorus removal was found to be inversely proportional to the duration of aeration off time in each IA cycle. The microscopic analysis revealed that the suspended and attached biomass had compact morphology and open floc structure, respectively. For each gram of volatile suspended solids, 165 and 148 mg of extracellular polymeric substances (EPS) were extracted from attached and suspended biomass, respectively, constituting carbohydrates (∼24%), proteins (∼31%), humic acids (∼28%), DNA (∼2%) and unknown substances (∼12%). The microbial diversities of suspended biomass in IFAS reactor were investigated using culture-dependent approach, which confirmed the presence of Clostridium spp., Pseudomonas spp., Bacillus spp., Escherichia coli spp., Nitrosococcus spp., Streptococcus spp., Acinetobacter spp., Betaproteobacteria outliers, Klebsiella pneumoniae, Klebsiella aerogenes, Serratia marcescens, Micrococcus, Proteus vulgaris spp., Actinomycetes spp., and Actinobacteria including Micromonospora spp. and Streptomyces spp. Molecular tools for diversity analyses were used for ammonia and nitrite oxidizer identification, such as Nitrospira and Nitrosococcus species. Denitrifiers include the species of Pseudomonas, Betaproteobacteria and Flavobacterium. Acinetobacter, Betaproteobacteria and Gammaproteobacteria were responsible for the phosphorus removal in the present system. Overall, the system performed efficiently showing Proteobacteria (59%), Acinetobacter (12%) and Bacteroidetes (11%) as the dominant bacterial groups. However, the dominance of the bacterial diversity varied with the IA cycle time numerating the maximum percentage of bacterial species during IA1 phase i.e. 2.5 h aeration/0.5 h non-aeration.


Assuntos
Ar , Reatores Biológicos/microbiologia , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/microbiologia , Amônia/metabolismo , Bactérias/metabolismo , Betaproteobacteria/metabolismo , Biomassa , Cidades , Humanos , Nitrogênio/metabolismo , Fósforo/análise , Fósforo/metabolismo , Esgotos/química , Gerenciamento de Resíduos/métodos , Águas Residuárias/análise
15.
Int J Syst Evol Microbiol ; 66(5): 2113-2120, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26907585

RESUMO

An investigation into the taxonomic position of Bacillus isronensis MTCC 7902T revealed that the strain shares a common phylogenetic lineage with Solibacillus silvestris MTCC 10789T. It displays considerable overlap in phenotypic properties with the genus Solibacillus, including endospore shape and position, oxidase and catalase activities, presence of iso-C15 : 0, C16 : 1ω7c alcohol and iso-C17 : 1ω7c as major cellular fatty acids, A4α-type cell-wall peptidoglycan, polar lipids and menaquinone pattern. These features reinforce the findings of molecular phylogenetic analyses based on 16S rRNA gene, gyrB gene and 16S-23S internal transcribed spacer (ITS) region sequences and, in line with the recommendations of Kämpfer et al. [Int J Syst Evol Microbiol 56 (2006), 781-786], provide justification for the transfer of Bacillus isronensis from the genus Bacillus to Solibacillus as Solibacillus isronensis comb. nov. The type strain is B3W22T ( = MTCC 7902T = DSM 21046T = JCM 13838T). An emended description of the genus Solibacillus is also provided.


Assuntos
Bacillus/classificação , Filogenia , Planococáceas/classificação , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , DNA Espaçador Ribossômico/genética , Ácidos Graxos/química , Genes Bacterianos , Lipídeos/química , Peptidoglicano/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Esporos Bacterianos , Vitamina K 2/química
16.
Int J Syst Evol Microbiol ; 66(12): 5228-5235, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27619232

RESUMO

The taxonomic position of a Gram-stain negative, non-violaceinpigmented bacterium isolated from an insecticide-contaminated site was characterized by a polyphasic approach. The bacterium was able to grow on three different halogenated compounds namely 1-hlorobutane, 1-hloropropane and 1,2-ichloroethane. As a critical step in the degradation of these haloalkanes, stoichiometric amounts of dechlorination were estimated. Based on selective enrichment method for three months, using a highly contaminated mixed chemical soil, a bacterium was obtained and designated as IITR-71T. Its versatility and novelty led us to further characterize it by polyphasic taxonomy. The 16S rRNA gene sequence (1446 bases) comparison showed highest similarity with those of members of the genus Chromobacterium with the most closely related species to strain IITR-71T being Chromobacterium aquaticum (99.3 %) followed by Chromobacterium haemolyticum (98.6 %) and Chromobacterium piscinae (97.1 %). The major ubiquinone was Q-8. Predominant polar lipids are phosphatidylethanolamine (PE), phosphatidylglycerol (PG) and diphosphatidylglycerol (DPG). The DNA G+C content of IITR-71T was estimated to be 61.2 mol%. The genotypic and phenotypic distinctiveness of IITR-71T and its phylogenetic relationships indicate that IITR-71T represents a novel species, for which the name Chromobacterium alkanivorans sp. nov. is proposed. The type strain is IITR-71T (=MTCC 11059T=JCM 30068T=KCTC 52433T).


Assuntos
Chromobacterium/classificação , Filogenia , Microbiologia do Solo , Alcanos/metabolismo , Técnicas de Tipagem Bacteriana , Composição de Bases , Chromobacterium/genética , Chromobacterium/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Sedimentos Geológicos/microbiologia , Halogenação , Índia , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
17.
Prep Biochem Biotechnol ; 46(5): 517-23, 2016 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26458110

RESUMO

In the last decade, much attention has been paid to bioremediation of Cr(VI) using various bacterial species. Cr(VI) remediation by indegeneous bacteria isolated from contaminated sites of a tannery industry located in Tamil Nadu, India, was investigated in this study. Three Cr(VI) resistant bacterial strains (TES-1, TEf-1, and TES-2) were isolated and selected based on their Cr(VI) reduction ability in minimal salt medium. Among these three bacterial strains, TES-1 was found to be most efficient in bioreduction, while TES-2 was only found to be Cr(VI) resistant and showed negligible bioreduction, whereas TEf-1 was observed to be most Cr(VI) tolerant. Potential for bioremediation of TES-1 and TEf-1 was further investigated at different concentrations of Cr(VI) in the range of 50 to 350 mg L(-1). TEf-1 showed prominent synchronous growth throughout the experiment, whereas TES-1 took a longer acclimatization time. Minimum inhibitory concentrations (MIC) of Cr(VI) for TES-1 and TEf-1 were approximated as 600 mg L(-1) and 750 mg L(-1), respectively. The kinetic behavior of Cr(VI) reduction by TES-1 and TEf-1 exhibited zero- and first-order removal kinetics for Cr(VI), respectively. The most efficient strain TES-1 was identified as Streptomyces sp. by gene sequencing of 16S rRNA.


Assuntos
Bactérias Aeróbias/metabolismo , Biodegradação Ambiental , Cromo/isolamento & purificação , Poluentes Ambientais/isolamento & purificação , Resíduos Industriais , Curtume , Bactérias Aeróbias/crescimento & desenvolvimento , Cromo/metabolismo , Poluentes Ambientais/metabolismo , Cinética
18.
Water Sci Technol ; 74(5): 1177-84, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27642837

RESUMO

In the present study, the effect of short-term organic shock loads (675, 799, 1,084 and 1,410 mg COD/L) on the treatment performance of a pilot-scale vermifilter (VF), employing an epigeic earthworm Eisenia fetida and treating synthetic domestic wastewater is investigated. The effect of organic shock loads on the performance and stability of vermifiltration reactor was evaluated to identify its feasibility in actual field conditions. Prior to the application of each organic shock load, normal loading conditions were maintained to achieve the pseudo steady state (PSS) conditions. The results showed satisfactory endurance against imposed organic shock loads with negligible reduction in chemical oxygen demand (COD) removals and it was almost similar to PSS condition with removal efficiencies of ∼ 66, 71, 67 and 68%, respectively. The experimental COD data fit well to first-order kinetic model, with a regression value of 0.95. At the end of all shock loads, the nutritional analysis of vermicompost obtained from the top layer of VF, showed increased concentration of total nitrogen (∼31 g/Kg) and total phosphorus (29 g/Kg). Besides, an augmented earthworm biomass, ∼23.2% on weight basis and ∼22% on number basis, was observed at the end of the study.


Assuntos
Análise da Demanda Biológica de Oxigênio , Reatores Biológicos , Animais , Biomassa , Cinética , Nitrogênio , Oligoquetos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias
19.
Water Sci Technol ; 73(7): 1511-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27054722

RESUMO

In this study, the effectiveness of polyvinyl alcohol (PVA) gel beads in treating domestic wastewater was investigated: a moving bed biofilm reactor (MBBR) configuration (oxic-anoxic and oxic) with 10% filling fraction of biomass carriers was operated in a continuously fed regime at temperatures of 25, 20, 15 and 6 °C with hydraulic retention times (HRTs) of 32 h, 18 h, 12 h and 9 h, respectively. Influent loadings were in the range of 0.22-1.22 kg N m(-3) d(-1) (total nitrogen (TN)), 1.48-7.82 kg chemical oxygen demand (COD) m(-3) d(-1) (organic) and 0.12-0.89 kg NH4(+)-N m(-3)d(-1) (ammonia nitrogen). MBBR performance resulted in the maximum TN removal rate of 1.22 kg N m(-3) d(-1) when the temperature and HRT were 6 °C and 9 h, respectively. The carbon removal rate at this temperature and HRT was 6.82 kg COD m(-3) d(-1). Ammonium removal rates ranged from 0.13 to 0.75 kg NH4(+)-N m(-3) d(-1) during the study. Total phosphorus and suspended solid removal efficiency ranged from 84 to 98% and 85 to 94% at an influent concentration of 3.3-7.1 mg/L and 74-356 mg/L, respectively. The sludge wasted from the MBBR exhibited light weight features characterized by sludge volume index value of 185 mL/g. Experimental data obtained can be useful in further developing the concept of PVA gel based wastewater treatment systems.


Assuntos
Biofilmes , Reatores Biológicos , Carbono/metabolismo , Nitrogênio/metabolismo , Álcool de Polivinil/química , Compostos de Amônio , Bactérias/metabolismo , Análise da Demanda Biológica de Oxigênio , Biomassa , Carbono/química , Nitrogênio/química , Fósforo , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , Poluentes Químicos da Água
20.
Int J Syst Evol Microbiol ; 65(11): 3794-3799, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26956594

RESUMO

A Gram-staining-positive, coccoid, halotolerant bacterial strain, designated SV-16T, was isolated from marine sediment and subjected to a polyphasic taxonomic study. The strain exhibited phenotypic properties that included chemotaxonomic characteristics consistent with its classification in the genus Salinicoccus. Growth occurred at temperatures in the range 25-37 °C (optimum 30 °C), at pH 7.0-11.0 (optimum pH 8.0) and at NaCl concentrations of up to 25.0% (optimum 15.0%). The highest level of 16S rRNA gene sequence similarity was with Salinicoccus carnicancri CrmT (98.6%) followed by Salinicoccus halodurans W24T (96.6%). The predominant polar lipids were diphosphatidylglycerol, phosphatidylinositol and phosphatidylglycerol. The major cellular fatty acids were iso-C15:0, anteiso-C15:0, iso-C17:0 and anteiso-C17:0. The draft genome of strain SV-16T consisted of 2,591,284 bp with a DNA G+C content of 48.7 mol%. On the basis of the phenotypic characteristics and genotypic distinctiveness of strain SV-16T, it should be classified within a novel species of the genus Salinicoccus, for which the name Salinicoccus sediminis sp. nov. is proposed. The type strain is SV-16T ( = MTCC 11832T = DSM 28797T).


Assuntos
Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Staphylococcaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Índia , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Staphylococcaceae/genética , Staphylococcaceae/isolamento & purificação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA