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1.
PLoS One ; 15(6): e0232831, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497096

RESUMO

The burden of enteric pathogens in poultry is growing after the ban of antibiotic use in animal production. Organic acids gained attention as a possible alternative to antibiotics due to their antimicrobial activities, improved nutrient metabolism and performance. The current study was conducted to evaluate the effectiveness of organic acid blend on broilers cecal microbiota, histomorphometric measurements, and short-chain fatty acid production in Salmonella enterica serovar Typhimurium challenge model. Birds were divided into four treatments, including a negative control, positive control challenged with S. Typhimurium, group supplemented with an organic acid blend, and birds supplemented with organic acid blend and Salmonella challenged. Results illustrate significant differences in feed conversion ratios and production efficiency factor between treatment groups, however, the influence of organic acid supplement was marginal. Organic acid blend significantly increased cecal acetic and butyric acids concentrations when compared to unsupplemented groups and resulted in minor alterations of intestinal bacterial communities.


Assuntos
Acetatos/metabolismo , Ração Animal , Butiratos/metabolismo , Galinhas/microbiologia , Suplementos Nutricionais , Ácidos Graxos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Doenças das Aves Domésticas/terapia , Salmonelose Animal/terapia , Salmonella typhimurium/efeitos dos fármacos , Animais , Ceco/microbiologia , Galinhas/metabolismo , Ácidos Graxos/administração & dosagem , Ácidos Graxos Voláteis/administração & dosagem , Ácidos Graxos Voláteis/farmacologia , Íleo/metabolismo , Íleo/ultraestrutura , Mananas/administração & dosagem , Microvilosidades/ultraestrutura , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/prevenção & controle , Distribuição Aleatória , Salmonelose Animal/microbiologia , Salmonelose Animal/prevenção & controle , Salmonella typhimurium/isolamento & purificação , Salmonella typhimurium/metabolismo
2.
Saudi J Biol Sci ; 24(5): 1094-1103, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28663710

RESUMO

Propolis is a gummy material made by honeybees for protecting their hives from bacteria and fungi. The main objective of this study is to determine the chemical compositions and concentrations of organic compounds in the extractable organic matter (EOM) of propolis samples collected from four different regions in Yemen. The propolis samples were extracted with a mixture of dichloromethane and methanol and analyzed by gas chromatography-mass spectrometry (GC-MS). The results showed that the total extract yields ranged from 34% to 67% (mean = 55.5 ± 12.4%). The major compounds were triterpenoids (254 ± 188 mg g-1, mainly α-, ß-amyryl and dammaradienyl acetates), n-alkenes (145 ± 89 mg g-1), n-alkanes (65 ± 29 mg g-1), n-alkanoic acids (40 ± 26 mg g-1), long chain wax esters (38 ± 25 mg g-1), n-alkanols (8 ± 3 mg g-1) and methyl n-alkanoates (6 ± 4 mg g-1). The variation in the propolis chemical compositions is apparently related to the different plant sources. The compounds of these propolis samples indicate that they are potential sources of natural bio-active compounds for biological and pharmacological applications.

3.
Mar Pollut Bull ; 124(1): 56-66, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28705628

RESUMO

Surface sediment samples from the coastal zone of Qatar were collected and analyzed to determine the characteristics, and sources of anthropogenic and biogenic hydrocarbons. The main compounds in these surface sediments included n-alkanes, methyl n-alkanoates, diterpenoids, hopanes, steranes, phthalate esters, polycyclic aromatic hydrocarbons (PAHs) and unresolved complex mixture (UCM). Their total concentrations ranged from 18.7±3.7-81.1±7.5ng/g (3.7±0.6-10.4±4.8%) for n-alkanes, 8.3±2.3-51±3.4ng/g (3.0±2.0-5.6±2.0%) for methyl n-alkanoates, 1.8±0.1-10.5±1.0ng/g (1.0±0.5-0.4±0.1%) for diterpenoids, 0.0-79.3±7.4ng/g (0.0-7.9±0.6%) for hopanes, 0.0-32.9±7.9ng/g (0.0-6.5±1.0%) for steranes, 0.7±0.1-36.3±3.4ng/g (0.1±0.1-1.9±3.4%) for phthalates, 0.30±0.2-7.8±0.7ng/g (0.02±0.04-0.42±0.72%) for PAHs, and 38±9-609±57ng/g (38.5±13.4-56.5±13.4%) for UCM. The major sources of these lipids were anthropogenic petroleum residues and plasticizers (80-89%), with lesser amounts from natural higher plants and microbial residues (11-20%). Petroleum residues and plasticizer inputs to the coastal sediments of Qatar likely affect the marine ecosystems and associated species groups as well as shallow coastal nursery and spawning areas.


Assuntos
Sedimentos Geológicos/análise , Hidrocarbonetos/análise , Poluição por Petróleo/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Hidrocarbonetos/classificação , Oceano Índico , Catar , Poluentes Químicos da Água/classificação
4.
Environ Sci Pollut Res Int ; 23(21): 21273-21287, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27497850

RESUMO

The main objectives of this work were to identify and determine the concentrations of polycyclic aromatic hydrocarbons (PAHs) and trace metals in carpet dust samples from various mosques of the city of Riyadh and to assess the health risks associated with the exposure to these pollutants. Therefore, 31 samples of mosque's carpet dust from Riyadh were collected. The results showed that 14 PAHs were present in the dust samples with concentrations ranged from 90 to 22,146 ng g-1 (mean = 4096 ± 4277 ng g-1) where low molecular weight compounds were dominant. The presence of PAHs were in the order of naphthalene > chrysene and benzo(b)fluoranthene > benzo(a)pyrene > acenaphthene and benzo(k)fluoranthene > pyrene and the absence of indeno(1,2,3-cd)pyrene and dibenz(a,h)anthracene. The diagnostic ratio coupled with principle component analysis (PCA) revealed mix sources of petrogenic from traffic, stack emission, and pyrogenic inputs from essence and perfumed wood burning. Trace metals were significant in the dust samples, and their concentrations decrease in the order of Zn, Mn, Cu, Cr, Pb, Ni, and V where Zn being the highest (94.4 ± 91.5 µg g-1) and indium was the lowest (1.9 ± 9.3 µg g-1). The trace metals were major in southern and central parts of Riyadh and followed the order of central Riyadh > southern Riyadh > western Riyadh > eastern Riyadh > northern Riyadh. Estimated risk based on the total PAHs was found to be 4.30 × 10-11 for adult and 1.56 × 10-11 for children. Elemental non-cancer risk for adults ranged from 7.9 × 10-4 for Co to 7.58 × 10-1 for Li and for children ranged from 3.70 × 10-3 for Co to 3.54 for Li. Policy implication and mitigations of PAHs in Riyadh and Saudi Arabia were highlighted.


Assuntos
Poeira/análise , Poluentes Ambientais/análise , Pisos e Cobertura de Pisos , Saúde , Hidrocarbonetos Policíclicos Aromáticos/análise , Oligoelementos/análise , Adulto , Criança , Cidades , Monitoramento Ambiental , Humanos , Medição de Risco , Arábia Saudita
5.
Environ Pollut ; 208(Pt B): 696-703, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26552533

RESUMO

Soil particles contain a variety of natural and anthropogenic organic components, and in urban areas can be considered as local collectors of pollutants. Surface soil samples were taken from ten urban areas in Riyadh during early winter of 2007. They were extracted with dichloromethane-methanol mixture and the extracts were analyzed by gas chromatography-mass spectrometry. The major compounds were unresolved complex mixture (UCM), plasticizers, n-alkanes, carbohydrates, n-alkanoic acids, hopanes, n-alkanols, and sterols. Vegetation detritus was the major natural source of organic compounds (24.0 ± 15.7%) in samples from areas with less human activities and included n-alkanes, n-alkanoic acids, n-alkanols, sterols and carbohydrates. Vehicular emission products and discarded plastics were the major anthropogenic sources in the soil particles (53.3 ± 21.3% and 22.7 ± 10.7%, respectively). The anthropogenic tracers were UCM, plasticizers, n-alkanes, hopanes and traces of steranes. Vegetation and human activities control the occurrence and distribution of natural and anthropogenic extractable organic matter in this arid urban area.


Assuntos
Misturas Complexas/análise , Clima Desértico , Monitoramento Ambiental/métodos , Lipídeos/análise , Poluentes do Solo/análise , Urbanização , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Compostos Orgânicos/análise , Plastificantes/análise , Arábia Saudita , Solo/química , Emissões de Veículos/análise
6.
PLoS One ; 10(6): e0128311, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26075382

RESUMO

Propolis is a gummy material produced by honey bees to protect their hives and currently has drawn the attention of researchers due to its broad clinical use. It has been reported, based only on observations, that honey bees also collect other non-vegetation substances such as paint or asphalt/tar to make propolis. Therefore, propolis samples were collected from bee hives in Riyadh and Al-Bahah, a natural area, Saudi Arabia to determine their compositional characteristics and possible sources of the neutral organic compounds. The samples were extracted with hexane and analyzed by gas chromatography-mass spectrometry. The results showed that the major compounds were n-alkanes, n-alkenes, methyl n-alkanoates, long chain wax esters, triterpenoids and hopanes. The n-alkanes (ranging from C17 to C40) were significant with relative concentrations varying from 23.8 to 56.8% (mean = 44.9+9.4%) of the total extracts. Their odd carbon preference index (CPI) ranged from 3.6 to 7.7, with a maximum concentration at heptacosane indicating inputs from higher plant vegetation wax. The relative concentrations of the n-alkenes varied from 23.8 to 41.19% (mean = 35.6+5.1%), with CPI = 12.4-31.4, range from C25 to C35 and maximum at tritriacontane. Methyl n-alkanoates, ranged from C12 to C26 as acids, with concentrations from 3.11 to 33.2% (mean = 9.6+9.5%). Long chain wax esters and triterpenoids were minor. The main triterpenoids were α- and ß-amyrins, amyrones and amyryl acetates. The presence of hopanes in some total extracts (up to 12.5%) indicated that the bees also collected petroleum derivatives from vicinal asphalt and used that as an additional ingredient to make propolis. Therefore, caution should be taken when considering the chemical compositions of propolis as potential sources of natural products for biological and pharmacological applications. Moreover, beekeepers should be aware of the proper source of propolis in the flight range of their bee colonies.


Assuntos
Abelhas , Hidrocarbonetos/química , Própole/química , Animais , Atmosfera/química , Cromatografia Gasosa-Espectrometria de Massas , Material Particulado/química , Arábia Saudita , Solo/química
7.
Springerplus ; 3: 253, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24926420

RESUMO

INTRODUCTION: Propolis is a sticky material mixed by honeybees to utilize it in protecting their hives from infection by bacteria and fungi. The therapeutic properties of propolis are due to its chemical composition with bio-active compounds; therefore, researchers are interested in studying its chemical constituents and biological properties. The main objective of this study is to determine the chemical compositions, characteristics and relative concentrations of organic compounds in the extractable organic matter of propolis samples collected from four different areas in Ethiopia. RESULTS: The propolis samples were extracted with a mixture of dichloromethane and methanol and analyzed by gas chromatography-mass spectrometry (GC-MS).The results showed that the total extract yields ranged from 27.2% to 64.2% (46.7 ± 19.1%). The major compounds were triterpenoids (85.5 ± 15.0% of the total extracts, mainly α-, ß-amyrins and amyryl acetates), n-alkanes (5.8 ± 7.5%), n-alkenes (6.2 ± 7.0%,), methyl n-alkanoates (0.4 ± 0.2%), and long chain wax esters (0.3 to 2.1%). CONCLUSION: The chemical compositions of these propolis samples indicate that they are potential sources of natural bio-active compounds for biological and pharmacological applications.

8.
Sci Total Environ ; 470-471: 180-92, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24140688

RESUMO

Shallow surface sediment samples from the southern part of the Shatt al-Arab River estuary of Iraq and the northwestern Arabian Gulf were analyzed for polar lipid compounds including n-alkanoic acids, n-alkanols, steroids and triterpenoids. The results showed that the n-alkanoic acids, methyl n-alkanoates and n-alkanols typically ranged from C12 to C32 with total concentrations of 3.2 to 108.2 µg g(-1)dwt sample, from C12 to C30 with totals of 1.1 to 18.9 µg g(-1)dwt sample, and from C14 to C32 at 1.8 to 112.6 µg g(-1)dwt sample, respectively. Steroids and triterpenoids were detected and included stenols, stanols, stenones, stanones, tetrahymanol, tetrahymanone and extended ßß-hopanes. The total steroid concentrations ranged from 2.8 to 78.4 µg g(-1)dwt sample, whereas the triterpenoids varied from 0.05 to 7.6 µg g(-1)dwt sample. The simple regression analysis of the results and the spatial distribution patterns of the identified organic tracers indicated that the inter-compound relationships were related mainly to their major sources. Cluster analysis and principal component analysis (PCA) of data set showed that the sampling sites are similar. These sources were allochthonous (terrestrial vegetation), autochthonous (plankton residues and bacteria in the sediments) and anthropogenic (sewage and petroleum).


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Rios/química , Poluentes Químicos da Água/análise , Iraque , Lipídeos/análise , Esteroides/análise
9.
Environ Sci Pollut Res Int ; 21(1): 558-67, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23812790

RESUMO

In an effort to assess the occurrence and sources of polycyclic aromatic hydrocarbons (PAHs) in the ambient air of Riyadh, Saudi Arabia, PM10 samples were collected during December 2010. Diagnostic PAH concentration ratios were used as a tool to identify and characterize the PAH sources. The results reflect high PM10 and PAH concentrations (particulate matter (PM) = 270-1,270 µg/m(3)). The corresponding average PAH concentrations were in the range of 18 ± 8 to 1,003 ± 597 ng/m(3) and the total concentrations (total PAHs (TPAHs) of 17 compounds) varied from 1,383 to 13,470 ng/m(3) with an average of 5,871 ± 2,830 ng/m(3). The detection and quantification limits were 1-3 and 1-10 ng/ml, respectively, with a recovery range of 42-80%. The ratio of the sum of the concentrations of the nine major non-alkylated compounds to the total (CPAHs/TPAHs) was 0.87 ± 0.10, and other ratios were determined to apportion the PM sources. The PAHs found are characteristic for emissions from traffic with diesel being a predominant source.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluição do Ar/estatística & dados numéricos , Arábia Saudita
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