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1.
Protein J ; 42(2): 112-124, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36905495

RESUMO

BACKGROUND: The health benefits of natural products have a long history. Chaga (Inonotus obliques) is used in traditional medicine and is an essential antioxidant for protecting the body from oxidants. Reactive oxygen species (ROS) are produced routinely due to metabolic processes. However, environmental pollution factors such as methyl tert-butyl ether (MTBE) can increase oxidative stress in the human body. MTBE is widely used as a fuel oxygenator that can harm health. The widespread use of MTBE has posed significant threats to the environment by polluting environmental resources, including groundwater. This compound can accumulate in the bloodstream by inhaling polluted air, with a strong affinity for blood proteins. The primary mechanism of MTBE's harmful effects is ROS production. The use of antioxidants may help reduce MTBE oxidation conditions. The present study proposes that biochaga, as an antioxidant, can reduce MTBE damage in the bovine serum albumin (BSA) structure. METHODS AND RESULTS: This study investigated the role of different concentrations of biochaga in the structural change of BSA in the presence of MTBE by biophysical methods such as UV-Vis, fluorescence, FTIR spectroscopy, DPPH radical inhibition method, aggregation test, and molecular docking. Research at the molecular level is critical to investigate the structural change of proteins by MTBE and the protective effect of the ideal dose (2.5 µg/ml) of biochaga. CONCLUSION: the results of spectroscopic examinations showed that the concentration of 2.5 µg/ml of biochaga has the least destructive effect on the structure of BSA in the presence and absence of MTBE, and it can play as an antioxidant.


Assuntos
Éteres Metílicos , Soroalbumina Bovina , Humanos , Espécies Reativas de Oxigênio/metabolismo , Simulação de Acoplamento Molecular , Antioxidantes/farmacologia , Éteres Metílicos/farmacologia , Éteres Metílicos/química , Éteres Metílicos/metabolismo
2.
Chemosphere ; 239: 124724, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31505447

RESUMO

Combination of sulfuric acid modified bagasse activated carbon-bone biochar beads and Acinetobacter indicus screened from petroleum contaminated soil was the best condition for gaseous methyl tert-butyl ether (MTBE) removal. It was found that H2SO4 modified bagasse AC in powder form had higher adsorption capacity (989.33 mg g-1) than that in bead form (1.94 mg g-1). In addition, bone biochar in powder form (3.51 mg g-1) also had higher adsorption capacity than that in bead form (1.63 mg g-1). This was the fact that material beads contained high moisture content that inhibited the penetration of gaseous MTBE into the material. And a mixed material of H2SO4 modified bagasse AC-bone biochar beads had the highest adsorption capacity (2.22 mg g-1) compared to individual H2SO4 modified bagasse AC beads (1.94 mg g-1) and bone biochar beads (1.63 mg g-1) due to a mixed material had more rough surface and high surface area on its material. So, gaseous MTBE can penetrate through this material more easily. Although the maximum adsorption capacity of H2SO4 modified bagasse AC in powder form was the highest but microorganism cannot sustain and survive in this form for a long time. Therefore, the material beads were more suitable for microorganism to grow and degrade gaseous MTBE. Microorganism can degrade MTBE and caused no secondary wastes. Moreover, A. indicus was a novel strain for MTBE removal that has not been previously reported. Therefore, a combination of A. indicus-mixed material beads was a good choice for MTBE removal in a biofilter system.


Assuntos
Acinetobacter/metabolismo , Celulose/química , Carvão Vegetal/química , Éteres Metílicos/química , Acinetobacter/isolamento & purificação , Adsorção , Biodegradação Ambiental , Células Imobilizadas , Poluição Ambiental , Gases , Éteres Metílicos/isolamento & purificação , Éteres Metílicos/metabolismo , Petróleo , Microbiologia do Solo , Ácidos Sulfúricos/química , Gerenciamento de Resíduos/métodos
3.
Biosci Rep ; 38(6)2018 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-30287506

RESUMO

Monocyclic monoterpenes have been recognized as useful pharmacological ingredients due to their ability to treat numerous diseases. Limonene and perillyl alcohol as well as their metabolites (especially perillic acid and its methyl ester) possess bioactivities such as antitumor, antiviral, anti-inflammatory, and antibacterial agents. These therapeutic properties have been well documented. Based on the aforementioned biological properties of limonene and its metabolites, their structural modification and development into effective drugs could be rewarding. However, utilization of these monocyclic monoterpenes as scaffolds for the design and developments of more effective chemoprotective agents has not received the needed attention by medicinal scientists. Recently, some derivatives of limonene metabolites have been synthesized. Nonetheless, there have been no thorough studies on their pharmacokinetic and pharmacodynamic properties as well as their inhibition against isoprenylation enzymes. In this review, recent research progress in the biochemical significance of limonene and its metabolites was summarized with emphasis on their antitumor effects. Future prospects of these bioactive monoterpenes for drug design and development are also highlighted.


Assuntos
Desenho de Fármacos , Limoneno/uso terapêutico , Neoplasias/tratamento farmacológico , Cicloexenos/química , Cicloexenos/metabolismo , Cicloexenos/uso terapêutico , Humanos , Limoneno/química , Limoneno/metabolismo , Éteres Metílicos/química , Éteres Metílicos/metabolismo , Éteres Metílicos/uso terapêutico , Monoterpenos/química , Monoterpenos/metabolismo , Monoterpenos/uso terapêutico , Neoplasias/patologia
4.
Microb Cell Fact ; 13: 83, 2014 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-24906383

RESUMO

BACKGROUND: Microbial lipids represent a valuable alternative feedstock for biodiesel production when oleaginous microbes are cultured with inexpensive substrates in processes exhibiting high yield and productivity. In this perspective, crude glycerol is among the most promising raw materials for lipid production, because it is the costless residual of biodiesel production. Thus, cultivation of oleaginous yeasts in glycerol-based media is attracting great interest and natural biodiversity is increasingly explored to identify novel oleaginous species recycling this carbon source for growth and lipid production. RESULTS: Thirty-three yeasts strains belonging to 19 species were screened for the ability to grow and produce intracellular lipids in a pure glycerol-based medium with high C/N ratio. A minority of them consumed most of the glycerol and generated visible lipid bodies. Among them, Candida freyschussii ATCC 18737 was selected, because it exhibited the highest lipid production and glycerol conversion yield. Lipid production in this strain was positively affected by the increase of C/N ratio, but growth was inhibited by glycerol concentration higher than 40 g/L. In batch cultures, the highest lipid production (4.6 g/L), lipid content of biomass (33% w/w), and lipid volumetric productivity (0.15 g/L/h) were obtained with 40 g/L glycerol, during the course of a 30-h process. Fed-batch cultivation succeeded in preventing substrate inhibition and in achieving a high cell-density culture. The improved lipid production and volumetric productivity reached the remarkable high level of 28 g/L and 0.28 g/L/h, respectively. The lipids accumulated by C. freyschussii ATCC 18737 have similar fatty acid composition of plant oil indicating their potential use as biodiesel feedstock. Calculated physicochemical properties of a biodiesel produced with the lipids from C. freyschussii ATCC 18737 are expected to meet the European and American standards, being equal to those of rapeseed and palm biodiesel. CONCLUSIONS: C. freyschussii ATCC 18737 could be considered an interesting microorganism for utilization in biofuel industry. Cultivation of this yeast in media containing crude glycerol should be investigated deeper in order to evaluate whether it may find application in the valorization of the waste of biodiesel manufacturing.


Assuntos
Candida/metabolismo , Glicerol/metabolismo , Microbiologia Industrial , Lipídeos/biossíntese , Técnicas de Cultura Celular por Lotes , Biocombustíveis , Candida/crescimento & desenvolvimento , Ácidos Graxos/metabolismo , Glicerol/química , Éteres Metílicos/metabolismo
5.
Water Res ; 47(2): 769-80, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23200508

RESUMO

For several pilot-scale constructed wetlands (CWs: a planted and unplanted gravel filter) and a hydroponic plant root mat (operating at two water levels), used for treating groundwater contaminated with BTEX, the fuel additive MTBE and ammonium, the hydrodynamic behavior was evaluated by means of temporal moment analysis of outlet tracer breakthrough curves (BTCs): hydraulic indices were related to contaminant mass removal. Detailed investigation of flow within the model gravel CWs allowed estimation of local flow rates and contaminant loads within the CWs. Best hydraulics were observed for the planted gravel filter (number of continuously stirred tank reactors N = 11.3, dispersion number = 0.04, Péclet number = 23). The hydroponic plant root mat revealed lower N and pronounced dispersion tendencies, whereby an elevated water table considerably impaired flow characteristics and treatment efficiencies. Highest mass removals were achieved by the plant root mat at low level: 98% (544 mg m⁻² d⁻¹), 78% (54 mg m⁻² d⁻¹) and 74% (893 mg m⁻² d⁻¹) for benzene, MTBE and ammonium-nitrogen, respectively. Within the CWs the flow behavior was depth-dependent, with the planting and the position of the outlet tube being key factors resulting in elevated flow rate and contaminant flux immediately below the densely rooted porous media zone in the planted CW, and fast bottom flow in the unplanted reference.


Assuntos
Poluição Ambiental , Recuperação e Remediação Ambiental/métodos , Água Subterrânea/química , Limnologia/métodos , Modelos Estruturais , Poluentes Químicos da Água/análise , Áreas Alagadas , Benzeno/análise , Benzeno/química , Carcinógenos Ambientais/análise , Carcinógenos Ambientais/química , Carcinógenos Ambientais/metabolismo , Sedimentos Geológicos/química , Alemanha , Hidroponia , Éteres Metílicos/análise , Éteres Metílicos/química , Éteres Metílicos/metabolismo , Petróleo/análise , Projetos Piloto , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Poaceae/crescimento & desenvolvimento , Poaceae/metabolismo , Compostos de Amônio Quaternário/análise , Compostos de Amônio Quaternário/química , Especificidade da Espécie , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo , Poluição Química da Água
6.
Environ Technol ; 33(16-18): 1937-43, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23240186

RESUMO

A laboratory-scale anaerobic sequencing batch reactor was used to evaluate treatment of a synthetic substrate mixture representing petrochemical wastewater containing methyl tert-butyl ether (MTBE), ethanol and acetic acid. Influent MTBE concentrations were 5, 10 and 50 mg/l (corresponding to MTBE loading rates of 0.2, 0.4 and 2 mg/l.d) with overall organic loading rates (OLRs) of 1.51, 3.23 and 3.25 g COD/1.d, respectively. These OLRs resulted in removal efficiencies for MTBE of 78%, 98% and 88%. Removal efficiencies for chemical oxygen demand were 85% and 90% with influent MTBE concentrations of 5 and 10mg/l, but were significantly reduced to 72% with influent MTBE concentrations of 50mg/l. During all reactor runs, effluent concentrations oftert-butyl alcohol (TBA) were below the detection limit. Batch degradation of the organic substrate mixture demonstrated initial inhibitory effects when exposed to MTBE concentrations of 50 mg/l and complete inhibition with MTBE concentrations above 2000 mg/l. It is interesting to note that in batch tests using MTBE as the sole organic substrate (initial MTBE concentrations of 50, 100 and 200 mg/l), the specific methanogenic activity decreased to below detection within the first 96 hours, but following a 72-hour lag phase the methane production increased again. Based on low volatile fatty acid (VFA) concentration, disappearance of TBA peaks and no findings of any other intermediate via gas chromatography/mass spectrometry, while the MTBE concentration is still high, it can be suggested that during the batch tests the breakdown of gas production and the following lag phase were the direct effect of higher MTBE concentrations (more than 50 mg/l) and not because of the TBA or VFA accumulations.


Assuntos
Reatores Biológicos , Éteres Metílicos/metabolismo , Petróleo , Purificação da Água , terc-Butil Álcool/metabolismo , Anaerobiose , Ácidos Graxos Voláteis/análise , Metano/análise
7.
Biomacromolecules ; 13(5): 1615-24, 2012 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-22520025

RESUMO

Three series of model homogalacturonans (HGs) covering a large range of degree of methylesterification (DM) were prepared by chemical and/or enzymatic means. Randomly demethylesterified HGs, HGs containing a few long demethylesterified galacturonic acid stretches, and HGs with numerous but short demethylesterified blocks were recovered. The analysis of the degradation products generated by the action of a purified pectin lyase allowed the definition of two new parameters, the degree of blockiness, and the absolute degree of blockiness of the highly methylesterified stretches (DBMe and DB(abs)Me, respectively). By combining this information with that obtained by the more traditional endopolygalacturonase digestion, the total proportion of degradable zones for a given DM was measured and was shown to permit a clear differentiation of the three types of HG series over a large range of DM. This double enzymatic approach will be of interest to discriminate industrial pectin samples exhibiting different functionalities and to evaluate pectin fine structure dynamics in vivo in the plant cell wall, where pectin plays a key mechanical role.


Assuntos
Éteres Metílicos/metabolismo , Pectinas/metabolismo , Poligalacturonase/metabolismo , Éteres Metílicos/química , Modelos Moleculares , Pectinas/química , Poligalacturonase/química
8.
Environ Sci Technol ; 46(9): 4757-66, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22455373

RESUMO

Although the uniform initial hydroxylation of methyl tert-butyl ether (MTBE) and other oxygenates during aerobic biodegradation has already been proven by molecular tools, variations in carbon and hydrogen enrichment factors (ε(C) and ε(H)) have still been associated with different reaction mechanisms (McKelvie et al. Environ. Sci. Technol. 2009, 43, 2793-2799). Here, we present new laboratory-derived ε(C) and ε(H) data on the initial degradation mechanisms of MTBE, ethyl tert-butyl ether (ETBE), and tert-amyl methyl ether (TAME) by chemical oxidation (permanganate, Fenton reagents), acid hydrolysis, and aerobic bacteria cultures (species of Aquincola, Methylibium, Gordonia, Mycobacterium, Pseudomonas, and Rhodococcus). Plotting of Δδ(2)H/ Δδ(13)C data from chemical oxidation and hydrolysis of ethers resulted in slopes (Λ values) of 22 ± 4 and between 6 and 12, respectively. With A. tertiaricarbonis L108, R. zopfii IFP 2005, and Gordonia sp. IFP 2009, ε(C) was low (<|-1|‰) and ε(H) was insignificant. Fractionation obtained with P. putida GPo1 was similar to acid hydrolysis and M. austroafricanum JOB5 and R. ruber DSM 7511 displayed Λ values previously only ascribed to anaerobic attack. The fractionation patterns rather correlate with the employment of different P450, AlkB, and other monooxygenases, likely catalyzing ether hydroxylation via different transition states. Our data questions the value of 2D-CSIA for a simple distinguishing of oxygenate biotransformation mechanisms, therefore caution and complementary tools are needed for proper interpretation of groundwater plumes at field sites.


Assuntos
Bactérias Aeróbias/metabolismo , Etil-Éteres/metabolismo , Éteres Metílicos/metabolismo , Tosilarginina Metil Éster/metabolismo , Biodegradação Ambiental , Etil-Éteres/química , Ácido Clorídrico/química , Peróxido de Hidrogênio/química , Hidrólise , Ferro/química , Compostos de Manganês/química , Éteres Metílicos/química , Oxirredução , Óxidos/química , Tosilarginina Metil Éster/química
9.
Sheng Wu Gong Cheng Xue Bao ; 25(6): 941-5, 2009 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-19777826

RESUMO

We used immobilized lipase from Candida sp. 99-125 to produce fatty acid methyl esters (FAMEs) from crude oil and methanol. We studied the effects of phospholipids on activity of immobilized lipase, reaction velocity, stability of immobilized lipase and the stability of immobilized lipase in crude and refined oil. Results showed that the activity of the lipase immersed in petroleum ether with 1% phospholipids dropped more quickly than the lipase in petroleum ether without phospholipids. When soybean oil was used without phospholipids as material, the FAMEs yield of 15 min was 26.2%, whereas the yield decreased to 12.4% when there were 5% phospholipids in the soybean oil. However when the phospholipids content was below 1%, the stability of the lipase did not change obviously. The lipase was stable when used to catalyze crude soybean oil and crude jatropha oil, after 10 cycles the FAMEs yield was still above 70%. This lipase showed great potential for industrial production of biodiesel from crude oil.


Assuntos
Biocombustíveis/análise , Candida/metabolismo , Lipase/metabolismo , Petróleo/metabolismo , Candida/enzimologia , Enzimas Imobilizadas , Ácidos Graxos/metabolismo , Metanol/metabolismo , Éteres Metílicos/metabolismo , Fosfolipídeos/metabolismo
10.
J Hazard Mater ; 167(1-3): 860-5, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19231071

RESUMO

Supplements with readily metabolizable organic substrates were investigated to increase the biomass and enhance degradation of methyl tert-butyl ether (MTBE) due to the low biomass yield of MTBE which has been one of the factors for low-rate MTBE degradation. The influence of various organic substrates on the rate of aerobic degradation of methyl tert-butyl ether (MTBE) by Methylibium petroleiphilum PM1 was investigated, and only yeast extract (YE), beef extract and tryptone exhibited stimulatory effect. With the concentration of each substrate being 100 mg/L, the average MTBE removal rate could increase to 1.29, 1.20 and 1.04 mg/(Lh), respectively, in comparison with 0.71 mg/(Lh) when carried out in medium without addition. The stimulatory effects of YE addition, as well as induction period required by MTBE degradation, varied dramatically with the storage conditions, pre-culture medium and concentrations of the inoculums. The extent of stimulatory effects of YE might be closely related to the proportion of induction period in the total time of MTBE-degradation. The removal efficiency increased from about 50% to 90.5% with the addition of YE in a packed-bed reactor loaded with calcium alginate immobilized cells.


Assuntos
Meios de Cultura/química , Éteres Metílicos/metabolismo , Aerobiose , Alginatos , Biodegradação Ambiental , Biomassa , Burkholderia/metabolismo , Células Imobilizadas , Ácido Glucurônico , Ácidos Hexurônicos , Cinética , Metabolismo , Especificidade por Substrato
11.
Phytochemistry ; 65(19): 2679-84, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15464155

RESUMO

A medium chain length fatty acid, [1-(14C)] lauric acid (12:0) was administered to the detached leaves of Artemisia and was incorporated into major lipids, including phospholipids and galactolipids. [1-(14C)]12:0 was elongated and desaturated into linolenic acid (18:3). In detached leaves of both Artemisia and Arabidopsis thaliana ecotype Columbia, radioactivity from [14C]18:3 was incorporated into jasmonic acid (JA) and methyl jasmonate (MJ). Higher amounts of [14C]JA were measured in Artemisia than Arabidopsis leaves. In Artemisia, [14C]JA was actively metabolized into [14C]MJ. Extracts prepared from the leaves of Artemisia, exhibited higher in vitro JA methyltransferase activity than those from Arabidopsis.


Assuntos
Arabidopsis/metabolismo , Artemisia/metabolismo , Ciclopentanos/metabolismo , Ácidos Láuricos/metabolismo , Metabolismo dos Lipídeos , Radioisótopos de Carbono , Lipídeos/química , Éteres Metílicos/química , Éteres Metílicos/metabolismo , Estrutura Molecular , Oxilipinas , Folhas de Planta/metabolismo
12.
Microb Ecol ; 48(1): 120-7, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15164240

RESUMO

A growing body of evidence now supports the isolation of microorganisms from ancient materials. However, questions about the stringency of extraction methods and the genetic relatedness of isolated organisms to their closest living relatives continue to challenge the authenticity of these ancient life forms. Previous studies have successfully isolated a number of spore-forming bacteria from organic and inorganic deposits of considerable age whose survival is explained by their ability to enter suspended animation for extended periods of time. However, despite a number of putative reports, the isolation of non-spore-forming bacteria and an explanation for their survival have remained enigmatic. Here we describe the isolation of non-spore-forming cocci from a 120-million-year-old block of amber, which by genetic, morphological, and biochemical analyses are identified as belonging to the bacterial species Micrococcus luteus. Although comparison of 16S rRNA sequences from the ancient isolates with their modern counterparts is unable to confirm the precise age of these bacteria, we demonstrate, using complementary molecular and cell biological techniques, evidence supporting the view that these (and related modern members of the genus) have numerous adaptations for survival in extreme, nutrient-poor environments, traits that will assist in this bacteria's persistence and dispersal in the environment. The bacteria's ability to utilize succinic acid and process terpine-related compounds, both major components of natural amber, support its survival in this oligotrophic environment.


Assuntos
Fósseis , Micrococcus luteus/genética , Micrococcus luteus/metabolismo , Filogenia , Âmbar , Sequência de Bases , Análise por Conglomerados , Meios de Cultura , Evolução Molecular , Ácidos Graxos/metabolismo , Fluorescência , Israel , Éteres Metílicos/metabolismo , Micrococcus luteus/isolamento & purificação , Micrococcus luteus/ultraestrutura , Microscopia Eletrônica , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
13.
Toxicol Ind Health ; 12(5): 697-721, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8989848

RESUMO

In this paper the wastewater treatment of organic compounds, particularly the water soluble (polar) compounds in refinery effluents, is simulated by addressing biodegradation, adsorption, and stripping/volatilization. The study examines pollutant data from two refineries in Norway and one in the United States. Previously, little attention has been paid to polar compounds. However, they are present in effluents, sometimes in large amounts, and are difficult to characterize and quantify. The study shows that many polar compounds, including the recently introduced methyl-tertiary-butyl-ether, are biodegraded by < 10% in simulated wastewater treatment. The concentrations of some polymers are barely reduced at all, and some metabolites of nonionic surfactants increase in toxicity along the route of degradation, resulting in an end product of the highest toxicity. The study demonstrates that of the substances entering the treatment systems, the residual of selected polar compounds is 38% of the incoming amount, while oil is reduced to 8%. It can be inferred from the study that polar compounds are contaminants, many of which may pose a pollution problem, and that reduction of polar compounds in effluents should be carried out upstream at the source of pollution, rather than downstream by end-of-pipe treatment.


Assuntos
Éteres Metílicos/metabolismo , Petróleo/metabolismo , Poluentes Químicos da Água/metabolismo , Adsorção , Biodegradação Ambiental , Guias como Assunto , Resíduos Industriais , Sistemas de Informação , Éteres Metílicos/química , Modelos Teóricos , Noruega , Polímeros , Reprodutibilidade dos Testes , Volatilização , Gerenciamento de Resíduos/normas , Purificação da Água
14.
Lloydia ; 38(2): 131-4, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-1134211

RESUMO

Callus cultures were extablished from the seedlings of Cassia tora on a chemically defined medium supplemented with 2, 4-D and kinetin. A phytochemical investigation of callus tissues demonstrated the presence of chrysophanol, emodin, physcion, and an unidentified pigment, all of which are contained in the seeds of the original plant. The maximum content of antraquinones on a fresh weight basis was 0.334 percent, which is higher than the content of total anthraquinones in the dry seeds. Furthermore, it was shown that the production of these compounds is influenced by the concentrations of auxin and cytokinin supplied to the culture medium.


Assuntos
Antraquinonas/biossíntese , Plantas Medicinais/metabolismo , Ácido 2,4-Diclorofenoxiacético , Antraquinonas/análise , Técnicas de Cultura , Relação Dose-Resposta a Droga , Éteres Metílicos/metabolismo , Doenças das Plantas , Reguladores de Crescimento de Plantas/farmacologia , Plantas Medicinais/efeitos dos fármacos , Sementes/análise
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