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1.
Environ Monit Assess ; 185(3): 2179-87, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22638725

RESUMO

Textile industry wastes raise a great concern due to their strong coloration and toxicity. The objective of the present work was to characterize the degradation and mineralization of textile effluents by advanced oxidative processes using either TiO(2) or TiO(2)/H(2)O(2) and to monitor the toxicity of the products formed during 6-h irradiation in relation to that of the in natura effluent. The results demonstrated that the TiO(2)/H(2)O(2) association was more efficient in the mineralization of textile effluents than TiO(2), with high mineralized ion concentrations (NH (4) (+) , NO (3) (-) , and SO (4) (2-) ) and significantly decreased organic matter ratios (represented by the chemical oxygen demand and total organic carbon). The toxicity of the degradation products after 4-h irradiation to Artemia salina L. was not significant (below 10 %). However, the TiO(2)/H(2)O(2) association produced more toxicity under irradiation than the TiO(2) system, which was attributed to the increased presence of oxidants in the first group. Comparatively, the photogenerated products of both TiO(2) and the TiO(2)/H(2)O(2) association were less toxic than the in natura effluent.


Assuntos
Resíduos Industriais , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/toxicidade , Purificação da Água/métodos , Animais , Artemia , Peróxido de Hidrogênio/química , Oxidantes Fotoquímicos/química , Processos Fotoquímicos , Indústria Têxtil , Titânio/química , Testes de Toxicidade , Raios Ultravioleta , Poluentes Químicos da Água/química
2.
J Chromatogr A ; 1194(1): 111-7, 2008 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-18468609

RESUMO

The quantification of monounsaturated and polyunsaturated trans fatty acids in partially hydrogenated fats by gas-liquid chromatography on a CP-Select CB-FAME capillary column was optimized using equivalent chain length values of fatty acids methyl esters that could coelute in the temperature range from 155 to 200 degrees C. The most appropriate temperature for the simultaneous determination of these trans isomers is around 197 degrees C. It is proposed a system to discriminate trans from cis octadecenoic fatty acid methyl esters based on the angular coefficient values of the equivalent chain length curves. The limits of detection and quantification were 0.28 and 0.93 mg g(-1). Quantification was performed in the range from 0.93 to 280 mg g(-1). Quantification accuracy was estimated by spike recovery of elaidic and trans-13-octadecenoic acids in hydrogenated fat samples. The obtained levels were from 97.60 to 103.28% for elaidic acid and from 98.12 to 99.27% for trans-13-octadecenoic acid. These results indicate that the accuracy of the methodology proposed for the quantification of monounsaturated and polyunsaturated trans fatty acids in hydrogenated fats is adequate.


Assuntos
Cromatografia Gasosa/métodos , Ácidos Graxos/análise , Sensibilidade e Especificidade
3.
Arch Latinoam Nutr ; 58(1): 87-90, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18589577

RESUMO

Nile tilapia (Oreochormis niloticus) fishbone is a fish part with unknown composition. After elaboration of flour fishbone of tilapia it was analysede. The results in 100 g of flour were: moisture (14.2%), protein (40.8%), total lipids (25.3%), and ash (18.3%), and mineral (in 100 g) was 2715.9 mg (calcium), 1.3 mg (iron), and 1132.7 mg (phosphorus). A total of 22 fatty acids were detected in fishbone flour total lipids (TL), being the major ones in (g) of total lipids: 16:0 (208.5 mg); 18:1n-9 (344.3 mg); and 18:2n-6 (109.6 mg). The concentration of linolenic acid--LNA (18:3n-3); eicopentaenoic acid--EPA (20:5n-3), and docosahexaenoic acid--DHA (22:6n-3) were (29.9 mg), (3.3 mg), and (12.9 mg), respectively. The content to saturated (SFA) were (296.2 mg), monounsaturated (MUFA) 415.0 mg, and polyunsaturated (PUFA) 175.6 mg. The ratio PUFA:MUFA:SFA was 1:2.4:1.7, and the ratio omega-6/omega-3 fatty acids were 2.8. The last is within the recommended values. The results show low concentrations of omega-3 fatty acids in flour. The value caloric and calcium, iron, phosphorus, and protein content the fishbone flour of tilapia may results a valuable alternative food in the human diet.


Assuntos
Ciclídeos , Ácidos Graxos/análise , Farinha/análise , Minerais/análise , Animais , Umidade , Valor Nutritivo
4.
Arch Latinoam Nutr ; 57(3): 273-7, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18271406

RESUMO

This study analyzed the effects of different concentrations of flaxseed oil (FO) on the proximate composition and the contents of alpha-linolenic acid (LNA, 18:3n-3), eicosapentaenoic (EPA, 20:5n-3), and docosahexaenoic (DHA, 22:6n-3) fatty acids in the liver of cultured Nile tilapia (Oreochromis niloticus). During the five-month culture period, tilapias were given diets with incremental concentrations of FO (0.00%; 1.25%; 2.50%; 3.75%, and 5.00%) as a replacement of sunflower oil (control). There was no significant difference in moisture and ash content in the liver between treatments. Protein values ranged from 12.1% (treatment II) to 13.9% (treatment V) and total lipids ranged from 5.6% (treatment V) to 7.2% (treatment II). There was no significant difference between most treatments. Fatty acid methyl esters (FAMEs) were quantitatively analyzed by capillary gas chromatography against a C(23:0), internal standard. Variations in concentrations (in mg g(-1) of total lipids) of fatty acids between treatment I and treatment V ranged from 4.2 to 51.2 (LNA), from 0.2 to 2.3 (EPA), and from 10.6 to 56.2 (DHA), respectively. This experiment demonstrated that increasing amounts of LNA in feed may markedly increase the amounts of LNA, EPA, and DHA in the liver of Nile tilapia.


Assuntos
Ração Animal , Ciclídeos , Gorduras Insaturadas na Dieta/metabolismo , Ácidos Graxos/análise , Óleo de Semente do Linho/administração & dosagem , Fígado/química , Animais , Cromatografia Gasosa , Gorduras Insaturadas na Dieta/administração & dosagem
5.
Anal Sci ; 22(4): 631-3, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16760612

RESUMO

This study examined the concentration (mg/g) of trans polyunsaturated fatty acid (TPFA) in five soybean oil brands by gas-liquid chromatography. Tricosanoic acid methyl ester was used as the internal standard. All samples analyzed presented trans 18:2 fatty and trans 18:3 acids in detectable amounts. The concentration of TPFA ranged from 5.8 to 30.2 mg/g, with a mean concentration value of 18.4 mg/g. Trans 18:3 fatty acids had the highest TPFA group concentrations, which ranged from 3.9 to 16.3 mg/g. The main isomer of this group presented the 9c, 12c, 15t configuration. For trans 18:2 fatty acids, concentrations ranged from 1.9 to 14.0 mg/g with a mean value of 8.1 mg/g. Alpha-linolenic acid (all cis) concentrations ranged from 30.7 to 60.6 mg/g and their degree of isomerization ranged from 6.0 to 31.5, indicating that the deodorization process varies from one producer to another. From per capita consumption of soybean oil brands in Brazil and their TPFA concentrations, it is possible to conclude that their contribution to the average TPFA intake per person in Brazil is 0.4 g/d.


Assuntos
Ácidos Graxos Insaturados/análise , Óleo de Soja/química , Ácidos Graxos trans/análise , Cromatografia Gasosa , Ácidos Graxos Insaturados/química , Metanol/química , Metilação , Ácidos Graxos trans/química , Ácido alfa-Linolênico/análise
6.
Meat Sci ; 74(2): 242-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22062831

RESUMO

The objective of this work was to evaluate the conjugated linoleic acid content (CLA), the fatty acid profile, and the chemical composition of the Longissimus muscle (LM) of steers and bulls finished in pasture systems. Fourteen 1/2 Nelore×1/2 Aberdeen Angus cattle were studied. The animals were slaughtered at approximately 20 months of age, with an approximate final liveweight of 480kg. Moisture, ash, fat, crude protein, cholesterol, and fatty acid contents of Longissimus muscle were determined. Steer muscle had a higher lipid content (3.38%) than that of bulls (1.71%). Total n-3 fatty acids were higher in bulls. The amounts of CLA in steer and bull fat were similar, but the CLA content in steer muscle was higher (47.99mg100g(-1) in LM) than that in bull muscle (23.24mg100g(-1) in LM).

7.
Food Funct ; 6(9): 3081-90, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26211429

RESUMO

Among the large number of scientifically unstudied fruits from the Amazonia biome, Couepia bracteosa acts as an interesting source of bioactive compounds, such as phenolic compounds and carotenoids, which may be used for protecting human health against oxidative damage. For the first time, the phenolic compounds and carotenoids in extracts obtained from the pulp, shell and seeds of C. bracteosa fruits are reported, as well as their in vitro scavenging capacities against some reactive oxygen species (ROS) and reactive nitrogen species (RNS). The shell extract presented the highest phenolic compound and carotenoid contents (5540 and 328 µg per g extract, dry basis, respectively), followed by the pulp and seed extracts. The major phenolic compound was acacetin sulphate (one methoxy and two OH groups) (62%) in the shells; however, only seeds presented apigenin sulphate (three OH groups), in which it was the major compound (44%). The high content of apigenin sulphate may explain why the seed extract had the highest scavenging efficiency against all tested ROS/RNS among the studied extracts. Regarding carotenoids, all-trans-neochrome (17%) and all-trans-ß-carotene (16%) were the major carotenoids in the pulp extracts, while all-trans-lutein (44%) was the most prevalent in the shell extracts and all-trans-α-carotene (32%) and all-trans-ß-carotene (29%) were the major ones in the seed extracts.


Assuntos
Chrysobalanaceae/química , Sequestradores de Radicais Livres/química , Frutas/química , Extratos Vegetais/química , Espécies Reativas de Nitrogênio/química , Espécies Reativas de Oxigênio/química , Sementes/química , Espectrometria de Massas , Estrutura Molecular
8.
J Agric Food Chem ; 57(1): 196-200, 2009 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-19055364

RESUMO

Different trademarks of green mate and mate tea ( Ilex paraguariensis St. Hil.) were employed in this work, the aim of which was to compare the fractionation of Al from green mate and mate tea (roasted mate) and from their infusions. Using the flame atomic absorption spectrometry technique, contents determined for Al leached to green mate and mate tea infusions varied from 12.8 to 18.1% and from 5.9 to 10.6%, respectively. The concentrations of phenolics in infusions were determined using the Folin-Ciocalteu method, and the presence of melanoidins was also evaluated. The results showed that phenolic compounds are the major contributors to the leached Al in green mate infusions, but melanoidins also contribute in the case of infusions prepared from the mate tea. By employing a chelating resin batch procedure, it was observed that Al was predominantly in relatively inert forms, mainly in the case of mate tea infusions (50-70%).


Assuntos
Alumínio/isolamento & purificação , Temperatura Alta , Ilex paraguariensis/química , Alumínio/análise , Alumínio/química , Bebidas/análise , Fracionamento Químico , Flavonoides/análise , Fenóis/análise , Polímeros/análise , Polifenóis , Espectrofotometria Atômica
9.
Arch. latinoam. nutr ; 50(4): 405-408, dic. 2000. tab, graf
Artigo em Inglês | LILACS | ID: lil-305286

RESUMO

El camu-camu (Myrciaria dubia), fruta nativa de la región Amazónica, es una de las fuentes mas ricas de vitamina C (de 2,4 hasta 3,0g/100g de pulpa en Brasil. Este trabajo tuvo por objeto la caracterización fisicoquímica de algunos nutrientes y la evaluación de la estabilidad de la vitamina C en l pulpa de camu-camu producida por el Instituto Agronómico de Paraná (IAPAR), Estación Experimental de Morretes (PR), Brasil. La determinación de vitamina C se realizó por titulación como iodato de potasio. La fruta cultivada en el estado de Paraná, presentó menor cantidad de vitamina C que la vitamina de la región Amazónica, posiblemente debido a las diferentes condiciones para el desarrollo de la planta, y consecuentemente de la fruta, así como la variación climática, humedad y características del suelo. Con relación a la estabilidad de la vitamina C en la pulpa almacenada en congelador a-18ºC, se pudo observar una disminución considerable (23 por ciento) en su concentración hasta el 28º día de (1,57 hasta 1,21g/100g), permaneciendo constante hasta el fin del experimento. Después de 335 dias de almacenaje, la cantidad encontrada fue de 1,16g/100g de pulpa, indicando una pérdida de 26 por ciento siendo esta cantidad aún superior a la encontrada en la mayoría de las fuentes de esta vitamina


Assuntos
Ácido Ascórbico , Composição de Medicamentos , Brasil , Ciências da Nutrição
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