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1.
Chemosphere ; 244: 125386, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050321

RESUMO

Polysulfone ultrafiltration (UF) and polypiperazine-amide nanofiltration (NF) membranes were first fabricated by phase inversion and interfacial polymerization, and then modified by the commonly used TiO2 on the membrane surface, respectively. Compared with the pristine UF and NF membranes, pure water flux decreased by 40.66% for modified UF membrane and 12.92% for modified NF membrane, while the contact angle of the modified membranes decreased from 66.5° to 35.3° for UF membrane and from 48.2° to37.7° for NF membrane. However, the membrane modified by TiO2 nanoparticles for both UF and NF membranes exhibited much better anti-fouling and separation performance for two types of oil-in-water emulsions with different droplet size (i.e., prepared oil-in-water emulsion with low salinity and oil produced water in Shengli oilfield, China). It was obvious that water flux of modified UF only slightly decreased and the stable water flux was 2.2 times and 15.6% higher than that of pristine membranes for the prepared oil-in-water emulsion and produced water, respectively. According to the five fouling models for UF, the TiO2 modified UF membrane could alleviate the fouling on membrane surface and greatly increase water flux by reducing the adsorption, deposition, blockage of membrane pores and formation of cake layer for two types of oil-in-water emulsion. For NF, water flux of the modified membrane increased by 66.1% and 22.8% for prepared oil-in-water emulsion and produced water, respectively. TiO2 coating effectively alleviated the oil adhesion and cake layer formation on the membrane surface.


Assuntos
Emulsões/química , Membranas Artificiais , Poluição por Petróleo , Piperazina/química , Polímeros/química , Sulfonas/química , Purificação da Água/métodos , China , Emulsões/isolamento & purificação , Óleos Industriais , Nanopartículas , Campos de Petróleo e Gás , Ultrafiltração/métodos , Ultrafiltração/normas
2.
Artigo em Inglês | MEDLINE | ID: mdl-31060207

RESUMO

Workers in various industries can be exposed to oil mists when oil-based fluids are aerosolized during work processes. Oil mists can be inhaled or deposited on the skin. Little research exists on the reproductive effects of oil mist exposure in pregnant workers. We aimed to investigate associations between occupational oil mist exposure in early pregnancy and a spectrum of birth defects using data from 22,011 case mothers and 8140 control mothers in the National Birth Defects Prevention Study. In total, 150 mothers were rated as exposed. Manufacturing jobs, particularly apparel manufacturing, comprised the largest groups of exposed mothers. Mothers of infants with septal heart defects (odds ratio (OR): 1.8, 95% confidence interval (CI): 1.0-3.3), and especially perimembranous ventricular septal defects (OR: 2.5, CI: 1.2-5.2), were more likely to be occupationally exposed to oil mists in early pregnancy than control mothers; and their rater-estimated cumulative exposure was more likely to be higher. This was the first U.S. study evaluating associations between oil mist exposure and a broad spectrum of birth defects. Our results are consistent with previous European studies, supporting a potential association between oil-based exposures and congenital heart defects. Further research is needed to evaluate the reproductive effects of occupational oil mist exposure.


Assuntos
Anormalidades Congênitas/etiologia , Óleos Industriais/efeitos adversos , Exposição Materna/efeitos adversos , Exposição Ocupacional/efeitos adversos , Complicações na Gravidez/induzido quimicamente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Lactente , Recém-Nascido , Razão de Chances , Gravidez , Estados Unidos , Adulto Jovem
3.
Plant Cell Physiol ; 60(6): 1274-1283, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31056666

RESUMO

As an important industrial feedstock, wax esters (WEs) have been used as lubricants in a number of technical processes. There is however currently no large-scale biological source for WE production and alteration in metabolic pathways of plant oils for producing WEs could be attractive to the commercial markets. Here, we present the breeding results of long-term studies on successful development of new crambe lines producing WEs through genetic engineering and cross breeding. The transgenic crambe lines producing WEs at over 25% of the total seed oil were first generated by introduction of the jojoba WE biosynthetic genes ScFAR and ScWS. Further improvement of the lines aiming at improving oxidative stability of WEs was achieved through introducing the CaFAD2-RNAi gene into these lines by crossing. The hybrid lines possessed similar agronomic traits to the wild type and a stable level of WEs over several generations, suggesting a high potential of crambe as an industrial crop for WE production.


Assuntos
Crambe (Planta)/metabolismo , Engenharia Metabólica , Melhoramento Vegetal , Óleos Vegetais/metabolismo , Crambe (Planta)/genética , Genes de Plantas , Engenharia Genética , Óleos Industriais , Engenharia Metabólica/métodos , Melhoramento Vegetal/métodos , Plantas Geneticamente Modificadas , Sementes/metabolismo , Ceras/metabolismo
4.
Commun Biol ; 2: 179, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31098412

RESUMO

Although metagenomics researches have illuminated microbial diversity in numerous biospheres, understanding individual microbial functions is yet difficult due to the complexity of ecosystems. To address this issue, we applied a metagenome-independent, de novo assembly-based metatranscriptomics to a complex microbiome, activated sludge, which has been used for wastewater treatment for over a century. Even though two bioreactors were operated under the same conditions, their performances differed from each other with unknown causes. Metatranscriptome profiles in high- and low-performance reactors demonstrated that denitrifiers contributed to the anaerobic degradation of heavy oil; however, no marked difference in the gene expression was found. Instead, gene expression-based nitrification activities that fueled the denitrifiers by providing the respiratory substrate were notably high in the high-performance reactor only. Nitrifiers-small minorities with relative abundances of <0.25%-governed the heavy-oil degradation performances of the reactors, unveiling an unexpected linkage of carbon- and nitrogen-metabolisms of the complex microbiome.


Assuntos
Carbono/metabolismo , Microbiota/fisiologia , Nitrificação/fisiologia , Esgotos/microbiologia , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Perfilação da Expressão Gênica , Óleos Industriais , Metagenômica , Microbiota/genética , Modelos Biológicos , Nitrificação/genética , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/microbiologia
5.
Workplace Health Saf ; 67(6): 288-293, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30614420

RESUMO

In the United States, there are more than 120,000 nail salons in which workers could be potentially exposed to a number of volatile organic compounds (VOCs) used in various procedures. Measuring workers exposure in the field is time-consuming and could be very expensive. The purpose of this study was to estimate the VOC levels in the proximity of workers in nail salons through simulating the application process of some popular nail polishes in a laboratory chamber. The worst-case scenario was defined as a worker's exposure during nail polish application to one set of fingernails every 15 minutes for an 8-hour shift (total nail sets = 32). Nail polish was applied on paper plates in a flow-controlled test chamber. Air was sampled during the application of five different nail polishes for 8 hours using passive air samplers and the experiment was triplicated. Passive samplers were used for VOCs and formaldehyde. In this worst-case scenario setting, a total of 17 VOCs were detected, with eight that were found in all the samples. The mean concentration of butyl acetate (161-330 ppm, parts per million) and ethyl acetate (440 ppm) exceeded the threshold limit value (TLV) of 150 ppm and 400 ppm, respectively. Formaldehyde was analyzed separately and the mean concentrations exceeded the TLV of 0.10 ppm in all types of nail polish, ranging from 0.12 ppm to 0.22 ppm. Occupational safety and health professionals could use these data to increase awareness of workers' potential exposure to high levels of VOCs in nail salons and recommend practical measures to reduce potential exposures.


Assuntos
Óleos Industriais/efeitos adversos , Exposição Ocupacional/estatística & dados numéricos , Compostos Orgânicos Voláteis/efeitos adversos , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Indústria da Beleza/estatística & dados numéricos , Formaldeído/administração & dosagem , Formaldeído/efeitos adversos , Humanos , Unhas/química , Estados Unidos , Compostos Orgânicos Voláteis/análise
7.
J Med Case Rep ; 12(1): 290, 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30301468

RESUMO

BACKGROUND: Transformer oil is used in oil-filled transformers for its insulating as well as coolant properties. Transformer oil ingestion for attempted suicide is seldom heard of. Our patient's case presented us with a major diagnostic as well as treatment challenge because we encountered such a case for the first time and were totally unaware of the fact that methanol might make up the main component of an aged transformer oil. CASE PRESENTATION: A 19-year-old Pakistani/Asian man was brought to our hospital with altered sensorium. He was found to have elevated anion gap acidosis, increased osmolal gap, and acute kidney injury. He had no evidence of rhabdomyolysis or hemolysis. Computed tomography of his head showed cerebral edema. He was resuscitated with intravenous fluids and bicarbonate. Three days later, he confessed taking transformer oil with suicidal intention. His clinical picture mimicked acute methanol intoxication. With an initial improvement in his neurological status, he started complaining of constant headache with episodes of agitation and delirium. His renal function continued worsening despite an adequate urine output. He showed a remarkable improvement in his neurological state after just one session of hemodialysis. CONCLUSIONS: There is evidence that aged transformer oil contains methanol, and a patient who consumes it can present with features mimicking acute methanol intoxication.


Assuntos
Acidose , Lesão Renal Aguda , Hidratação/métodos , Óleos Industriais , Metanol/toxicidade , Diálise Renal/métodos , Bicarbonato de Sódio/administração & dosagem , Equilíbrio Ácido-Base/efeitos dos fármacos , Acidose/sangue , Acidose/induzido quimicamente , Acidose/diagnóstico , Acidose/terapia , Lesão Renal Aguda/induzido quimicamente , Lesão Renal Aguda/diagnóstico , Lesão Renal Aguda/metabolismo , Lesão Renal Aguda/terapia , Edema Encefálico/diagnóstico por imagem , Edema Encefálico/etiologia , Tampões (Química) , Humanos , Óleos Industriais/análise , Óleos Industriais/toxicidade , Masculino , Tentativa de Suicídio , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Adulto Jovem
8.
Bioprocess Biosyst Eng ; 41(11): 1599-1610, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30027422

RESUMO

The aim of the present study was to investigate the separation of oil from water using a bench-scale DAF prototype with the addition of biosurfactants isolated from Pseudomonas cepacia CCT6659 and Bacillus cereus UCP1615. The best operating conditions for the DAF prototype were determined using a central composite rotatable design. The results demonstrated that the biosurfactants from P. cepacia and B. cereus increased the oil separation efficiency from 53.74% (using only microbubbles) to 94.11 and 80.01%, respectively. The prediction models for both DAF-biosurfactant systems were validated, showing an increase in the efficiency of the DAF process from 53.74% to 98.55 and 70.87% using the formulated biosurfactants from P. cepacia and B. cereus, respectively. The biosurfactant from P. cepacia was selected as the more promising product and used for the treatment of oily effluent from a thermoelectric plant, achieving removal rates ranging between 75.74 (isolated biosurfactant) and 95.70% (formulated biosurfactant), respectively.


Assuntos
Resíduos Industriais/análise , Tensoativos , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Ar , Bacillus cereus/classificação , Burkholderia cepacia/química , Desenho de Equipamento , Óleos Industriais/análise , Tensoativos/isolamento & purificação , Eliminação de Resíduos Líquidos/instrumentação , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/instrumentação
9.
Molecules ; 23(7)2018 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-29937532

RESUMO

The primary objective of this study is the synthesis of nanocapsules (NC) that allow the reduction of the adsorption process of surfactant over the porous media in enhanced oil recovery processes. Nanocapsules were synthesized through the nanoprecipitation method by encapsulating commercial surfactants Span 20 and Petro 50, and using type II resins isolated from vacuum residue as a shell. The NC were characterized using dynamic light scattering, transmission electron microscopy, Fourier transform infrared, solvency tests, softening point measurements and entrapment efficiency. The obtained NC showed spherical geometry with sizes of 71 and 120 nm for encapsulated Span 20 (NCS20), and Petro 50 surfactant (NCP50), respectively. Also, the NCS20 is composed of 90% of surfactant and 10% of type II resins, while the NCP50 material is 94% of surfactant and 6% of the shell. Nanofluids of nanocapsules dispersed in deionized water were prepared for evaluating the nanofluid­sandstone interaction from adsorption phenomena using a batch-mode method, contact angle measurements, and FTIR analysis. The results showed that NC adsorption was null at the different conditions of temperatures evaluated of 25, 50, and 70 °C, and stirring velocities up to 10,000 rpm. IFT measurements showed a reduction from 18 to 1.62 and 0.15 mN/m for the nanofluids with 10 mg/L of NCS20, and NCP50 materials, respectively. Displacements tests were conducted using a 20 °API crude oil in a quarter five-spot pattern micromodel and showed an additional oil recovery of 23% in comparison with that of waterflooding, with fewer pore volumes injected than when using a dissolved surfactant.


Assuntos
Óleos Industriais/análise , Nanocápsulas/química , Campos de Petróleo e Gás , Resinas Sintéticas/química , Tensoativos/química , Adsorção , Composição de Medicamentos/métodos , Humanos , Teste de Materiais , Nanocápsulas/ultraestrutura , Porosidade , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Temperatura , Água/química
10.
; ANVISA.
Recurso na Internet em Português | LIS - Localizador de Informação em Saúde, LIS-bvsms | ID: lis-LISBR1.1-46160

RESUMO

Cartilha: Veja quais cuidados tomar na hora de comprar, usar e armazenar produtos saneantes.


Assuntos
Saneantes , Desinfetantes , Clareadores , Inseticidas , Óleos Industriais , Detergentes , Rodenticidas
11.
Funct Integr Genomics ; 18(5): 533-543, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29730772

RESUMO

One of the main challenges in elimination of oil contamination from polluted environments is improvement of biodegradation by highly efficient microorganisms. Bacillus subtilis MJ01 has been evaluated as a new resource for producing biosurfactant compounds. This bacterium, which produces surfactin, is able to enhance bio-accessibility to oil hydrocarbons in contaminated soils. The genome of B. subtilis MJ01 was sequenced and assembled by PacBio RS sequencing technology. One big contig with a length of 4,108,293 bp without any gap was assembled. Genome annotation and prediction of gene showed that MJ01 genome is very similar to B. subtilis spizizenii TU-B-10 (95% similarity). The comparison and analysis of orthologous genes carried out between B. subtilis MJ01, reference strain B. subtilis subsp. subtilis str. 168, and close relative spizizenii TU-B-10 by microscope platform and various bioinformatics tools. More than 88% of 4269 predicted coding sequences in MJ01 had at least one similar sequence in genome of reference strain and spizizenii TU-B-10. Despite this high similarity, some differences were detected among encoding sequences of non-ribosome protein and bacteriocins in MJ01 and spizizenii TU-B-10. MJ01 has unique nucleotide sequences and a novel predicted lasso-peptide bacteriocin; it also has not any similar nucleotide sequence in non-redundant nucleotide data base.


Assuntos
Bacillus subtilis/genética , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Óleos Industriais/análise , Poluentes do Solo/metabolismo , Bacillus subtilis/classificação , Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , Bacteriocinas/biossíntese , Bacteriocinas/genética , Biodegradação Ambiental , Biologia Computacional , Mapeamento de Sequências Contíguas , Ontologia Genética , Lipopeptídeos/biossíntese , Lipopeptídeos/genética , Anotação de Sequência Molecular , Peptídeos Cíclicos/biossíntese , Peptídeos Cíclicos/genética , Filogenia , Solo/química , Microbiologia do Solo , Tensoativos/química , Tensoativos/metabolismo , Sequenciamento Completo do Genoma
13.
Mar Pollut Bull ; 129(2): 555-561, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29079303

RESUMO

Chemical dispersants are well-established as oil spill response tools. Several studies have emphasized their positive effects on oil biodegradation, but recent studies have claimed that dispersants may actually inhibit the oil biodegradation process. In this study, biodegradation of oil dispersions in natural seawater at low temperature (5°C) was compared, using oil without dispersant, and oil premixed with different concentrations of Slickgone NS, a widely used oil spill dispersant in Europe. Saturates (nC10-nC36 alkanes), naphthalenes and 2- to 5-ring polycyclic aromatic hydrocarbons (PAH) were biotransformed at comparable rates in all dispersions, both with and without dispersant. Microbial communities differed primarily between samples with or without oil, and they were not significantly affected by increasing dispersant concentrations. Our data therefore showed that a common oil spill dispersant did not inhibit biodegradation of oil at dispersant concentrations relevant for response operations.


Assuntos
Óleos Industriais/análise , Consórcios Microbianos , Água do Mar/química , Tensoativos/química , Poluentes Químicos da Água/análise , Biodegradação Ambiental , Biotransformação , Europa (Continente) , Consórcios Microbianos/efeitos dos fármacos , Consórcios Microbianos/genética , Poluição por Petróleo/análise , RNA Ribossômico 16S/genética , Água do Mar/microbiologia
14.
Biotechnol Appl Biochem ; 65(2): 138-144, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28649761

RESUMO

As promising alternatives to fossil-derived oils, microbial lipids are important as industrial feedstocks for biofuels and oleochemicals. Our broad aim is to increase lipid content in oleaginous yeast through expression of lipid accumulation genes and use Saccharomyces cerevisiae to functionally assess genes obtained from oil-producing plants and microalgae. Lipid accumulation genes DGAT (diacylglycerol acyltransferase), PDAT (phospholipid: diacylglycerol acyltransferase), and ROD1 (phosphatidylcholine: diacylglycerol choline-phosphotransferase) were separately expressed in yeast and lipid production measured by fluorescence, solvent extraction, thin layer chromatography, and gas chromatography (GC) of fatty acid methyl esters. Expression of DGAT1 from Arabidopsis thaliana effectively increased total fatty acids by 1.81-fold above control, and ROD1 led to increased unsaturated fatty acid content of yeast lipid. The functional assessment approach enabled the fast selection of candidate genes for metabolic engineering of yeast for production of lipid feedstocks.


Assuntos
Arabidopsis/genética , Biocombustíveis , Ácidos Graxos/genética , Microbiologia Industrial/métodos , Óleos Industriais , Microalgas/genética , Saccharomyces cerevisiae/genética , Arabidopsis/enzimologia , Arabidopsis/metabolismo , Biocombustíveis/análise , Biocombustíveis/microbiologia , Diacilglicerol Colinofosfotransferase/genética , Diacilglicerol Colinofosfotransferase/metabolismo , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Ácidos Graxos/metabolismo , Óleos Industriais/análise , Óleos Industriais/microbiologia , Engenharia Metabólica/métodos , Microalgas/enzimologia , Microalgas/metabolismo , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/metabolismo
15.
Palmas ; 39(1): 131-133, 2018. fotografía
Artigo em Espanhol | LILACS | ID: biblio-982153

RESUMO

El resultado alcanzado en este escenario ha sido muy importante, ya que en conjunto con los grandes productores de aceite de palma a nivel mundial, Malasia e Indonesia, se ha logrado hacer cara a las reservas presentadas (en especial) por la Unión Europea frente a la denominación del aceite. Este es un escalón adicional en el proceso normativo sobre este aceite, el cual ya cuenta con la norma local y regional (Comunidad Andina) y ha sido el fruto del trabajo conjunto de la Federación Nacional de Cultivadores de Palma de aceite (Fedepalma) y el Gobierno Nacional


The result achieved in this scenario has been very important, since in conjunction with the major palm oil producers worldwide, Malaysia and Indonesia, it has managed to face the reservations presented (especially) by the European Union against the denomination of the oil. This is an additional step in the normative process on this oil, which already has the local and regional norm (Andean Community) and has been the result of the joint work of the National Federation of Oil Palm Growers (Fedepalma) and the National government


Assuntos
História do Século XXI , Programas e Políticas de Nutrição e Alimentação , Óleos Industriais , Agroindústria
16.
J Oleo Sci ; 66(9): 981-990, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28794315

RESUMO

An offline solid-phase extraction (SPE) approach combined with a large-volume injection (LVI)-gas chromatography-flame ionization detector (LVI-GC-FID) is improved for routine analysis of mineral oil saturated hydrocarbons (MOSH) in vegetable oils. The key procedure of the method consists in using offline SPE columns for MOSH purification. The SPE column packed with 1% Ag-activated silica gel was used to separate MOSH from triglycerides and olefins in variety of vegetable oils. The eluent of MOSH fraction was only 3 mL and the concentration step was quick with little evaporation loss. The limit of quantification (LOQ) of the method was 2.5 mg/kg and the linearity ranged from 2 to 300 mg/kg. The accuracy was assessed by measuring the recoveries from spiked oil samples and was higher than 90%. Twenty-seven commercial vegetable oils were analyzed, and different levels of MOSH contamination were detected with the highest being 259.4 mg/kg. The results suggested that it is necessary to routinely detect mineral oil contamination in vegetable oils for food safety.


Assuntos
Cromatografia Gasosa/métodos , Ionização de Chama/métodos , Contaminação de Alimentos/análise , Hidrocarbonetos/análise , Óleos Industriais/análise , Óleo Mineral/análise , Óleos Vegetais/química , Extração em Fase Sólida/métodos , Inocuidade dos Alimentos
17.
Adv Colloid Interface Sci ; 247: 561-572, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28778342

RESUMO

Bacteria are often discussed as active colloids, self-propelled organisms whose collective motion can be studied in the context of non-equilibrium statistical mechanics. In such studies, the behavior of bacteria confined to interfaces or in the proximity of an interface plays an important role. For instance, many studies have probed collective behavior of bacteria in quasi two-dimensional systems such as soap films. Since fluid interfaces can adsorb surfactants and other materials, the stress and velocity boundary conditions at interfaces can alter bacteria motion; hydrodynamic studies of interfaces with differing boundary conditions are reviewed. Also, bacteria in bulk can become trapped at or near fluid interfaces, where they colonize and form structures comprising secretions like exopolysaccharides, surfactants, living and dead bacteria, thereby creating Films of Bacteria at Interfaces (FBI). The formation of FBI is discussed at air-water, oil-water, and water-water interfaces, with an emphasis on film mechanics, and with some allusion to genetic functions guiding bacteria to restructure fluid interfaces. At air-water interfaces, bacteria form pellicles or interfacial biofilms. Studies are reviewed that reveal that pellicle material properties differ for different strains of bacteria, and that pellicle physicochemistry can act as a feedback mechanism to regulate film formation. At oil-water interfaces, a range of FBI form, depending on bacteria strain. Some bacteria-laden interfaces age from an initial active film, with dynamics dominated by motile bacteria, through viscoelastic states, to form an elastic film. Others remain active with no evidence of elastic film formation even at significant interface ages. Finally, bacteria can adhere to and colonize ultra-low surface tension interfaces such as aqueous-aqueous systems common in food industries. Relevant literature is reviewed, and areas of interest for potential application are discussed, ranging from health to bioremediation.


Assuntos
Bacillus subtilis/química , Biofilmes/crescimento & desenvolvimento , Escherichia coli/química , Polissacarídeos Bacterianos/química , Pseudomonas aeruginosa/química , Ar/análise , Elasticidade , Óleos Industriais/análise , Propriedades de Superfície , Tensoativos/química , Termodinâmica , Viscosidade , Água/química
18.
Chemosphere ; 185: 412-422, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28710990

RESUMO

Ogale community in Rivers State, Nigeria is characterized by crude-oil contamination of its land resources. The present study aimed to evaluate the health risk and metal (Cd, Pb, Zn, Cr, and Ni) contamination level of the vegetable (Telfairia occidentalis), snail (Achatina achatina) and the catfish (Clarias gariepinus) collected from Ogale community. Samples collected from Elele Alimini community, a less polluted area was used as control. Oxidative damage was evaluated in tissues of snail and in the liver of catfish. The concentration of most of the tested metals in the food samples collected from the polluted sites were higher than those from the reference sites and in most cases exceeded the acceptable permissible limits. The accumulation of the metals by the food samples followed the order: T. occidentalis > A. achatina > C. gariepinus. The tissues of the snail from the polluted sites showed higher malondialdehyde (MDA) and lower glutathione (GSH) levels, and higher MDA and GSH levels in the fish liver compared to control values. The health risks associated with these metals in terms of dietary intake and target hazard quotients (THQs) showed higher non-carcinogenic effect and carcinogenic risks especially for Pb and Cd from the ingestion of Telfairia occidentalis and Achatina achatina from polluted sites. The health hazards due to metal pollution for the highly-exposed consumers of the food samples, especially in Ogale require attention. The oxidative stress response to accumulation status of metals provides a relevant tool for the assessment of metal pollution.


Assuntos
Monitoramento Ambiental , Poluição Ambiental , Óleos Industriais , Metais Pesados/análise , Estresse Oxidativo , Animais , Biomarcadores/análise , Peixes/metabolismo , Glutationa/metabolismo , Humanos , Malondialdeído/metabolismo , Nigéria , Medição de Risco , Caramujos/química , Caramujos/metabolismo , Verduras/química , Verduras/metabolismo
19.
J Oleo Sci ; 66(6): 551-556, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28566641

RESUMO

Rice bran oil (RBO) is healthy gift generously given by nature to mankind. RBO is obtained from rice husk, a byproduct of rice milling industry and is gaining lot of importance as cooking oil due to presence of important micronutrient, gamma oryzanol. Its high smoke point is beneficial for its use for frying and deep frying of food stuff. It is popular because of balanced fatty acid profile (most ideal ratio of saturated, monounsaturated and polyunsaturated fatty acids), antioxidant capacity, and cholesterollowering abilities. Rice bran wax which is secondary by-product obtained as tank settling from RBO is used as a substitute for carnauba wax in cosmetics, confectionery, shoe creams etc. It can be also used as a source for fatty acid and fatty alcohol. The article is intended to highlight for the importance of RBO and its applications.


Assuntos
Óleos Industriais , Óleos Vegetais/química , Anticolesterolemiantes/análise , Antioxidantes/análise , Cosméticos , Ácidos Graxos/análise , Álcoois Graxos , Fenilpropionatos , Óleo de Farelo de Arroz , Ceras
20.
Waste Manag ; 60: 451-459, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27349172

RESUMO

This study investigated physical and chemical modification of tyre-derived fuel oil (TDFO) obtained from pyrolysis of waste tyres and rubber products for application as an alternative fuel for compression ignition engines (CIE's). TDFO collected from a local waste tyre treatment facility was refined via a novel "oxidative gas-phase fractional distillation over 13× molecular sieves" to recover the light to medium fractions of the TDFO while oxidising and capturing some sulphur compounds in a gas phase. This was followed by desulphurization and chemical modification to improve cetane number, kinematic viscosity and fuel stability. The resulting fuel was tested in an ADE407T truck engine to compare its performance with petroleum diesel fuel. It was discovered that gas phase oxidative fractional distillation reduces the low boiling point sulphur compounds in TDFO such as mercaptans. Using petroleum diesel fuel as a reference, it was observed that the produced fuel has a lower cetane number, flash point and viscosity. On storage the fuel tends to form fibrous microstructures as a result of auto-oxidation of asphaltenes present in the fuel. Mixtures of alkyl nitrate, vinyl acetate, methacrylic anhydride, methyl-tert butyl ether, n-hexane and n-heptane were used to chemically modify the fuel in accordance with the minimum fuel specifications as per SANS 342. The engine performance tests results did not show any sign of engine ceasing or knocking effect. The power-torque trend was very consistent and compared well with petroleum diesel fuelled engine. The levels of total sulphur are still considerably high compared to other cleaner fuel alternatives derived from zero sulphur sources.


Assuntos
Óleos , Resíduos , Óleos Industriais , Óleos/química , Enxofre , Viscosidade , Gerenciamento de Resíduos/métodos
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