Fatty acid profile in vertical strata of elephant grass subjected to intermittent stocking

ABSTRACT The milk and meat from animals with a pasture-based diet have higher proportions of CLA and C18:3 and lower omega-6:omega-3 ratios than products from animals with diets based on corn silage and concentrate. However, most of the published studies have evaluated fatty acid profiles in temperate climate grasses and the literature with tropical grasses is scarce. Thus, the aim of this study was to evaluate the morphological and fatty acid compositions in the vertical strata of elephant grass (Pennisetum purpureum Schum.) swards subjected to grazing heights (90 or 120 cm pre-grazing heights) and levels of defoliation (50% or 70% removal of the initial pre-grazing height). There were no interactions among pre-grazing height, the level of defoliation and grazing stratum. However, higher proportion of C18:3 (58% and 63%) was found in the 90-cm swards and in the half upper stratum. A higher proportion of C18:3 was associated with a higher leaf proportion and crude protein content. Thus, the upper stratum of sward or a grazing management scheme (e.g. first-last stocking) resulting in a higher proportion of leaves and crude protein both provide higher proportions of C18:3 to animals grazing in elephant grass swards.

Fatty acid profile in vertical strata of elephant grass subjected to intermittent stocking.

The milk and meat from animals with a pasture-based diet have higher proportions of CLA and C18:3 and lower omega-6:omega-3 ratios than products from animals with diets based on corn silage and concentrate. However, most of the published studies have evaluated fatty acid profiles in temperate climate grasses and the literature with tropical grasses is scarce. Thus, the aim of this study was to evaluate the morphological and fatty acid compositions in the vertical strata of elephant grass (Pennisetum purpureum Schum.) swards subjected to grazing heights (90 or 120 cm pre-grazing heights) and levels of defoliation (50% or 70% removal of the initial pre-grazing height). There were no interactions among pre-grazing height, the level of defoliation and grazing stratum. However, higher proportion of C18:3 (58% and 63%) was found in the 90-cm swards and in the half upper stratum. A higher proportion of C18:3 was associated with a higher leaf proportion and crude protein content. Thus, the upper stratum of sward or a grazing management scheme (e.g. first-last stocking) resulting in a higher proportion of leaves and crude protein both provide higher proportions of C18:3 to animals grazing in elephant grass swards.

Ecological risk analysis of pesticides used on irrigated rice crops in southern Brazil.

Based on studies conducted in the past decade in the southern region of Brazil to determine residue levels of the pesticides normally used on irrigated rice crops, changes can be observed in relation to the presence of pesticides in the waters of the main river basins in Santa Catarina State. In previous harvests, the presence of residues of 7 pesticides was determined, with the herbicide bentazon and the insecticide carbofuran being the products showing highest frequency. Following toxicological tests conducted with 8 different test organisms, deterministic and probabilistic risk analysis was performed to assess the situation of the river basins in areas used for the production of irrigated rice. Of the species tested, the herbicide bentazon showed greatest toxicity toward plants, but did not present an ecological risk because in the worst-case scenario the highest concentration of this pesticide in the environment is 37 times lower than the lowest EC50/LC50 value obtained in the tests. The insecticide carbofuran, which had the highest toxicity toward the organisms used in the tests, presented an ecological risk in the deterministic analysis, but without any associated probability. The results highlight the need for increased efforts in training farmers in crop management practices and for the continual monitor of water bodies for the presence of pesticide residues.

Ação sistêmica e translaminar do óleo de nim visando ao controle de Tuta absoluta (Meyrick) (Lep: Gelechiidae) em tomateiro / Systemic and translaminar action of neem oil for the control of Tuta absoluta (Meyrick) (Lep: Gelechiidae) in tomato

A traça Tuta absoluta (Meyrick) é o inseto-praga que mais compromete a produção do tomateiro. Basear o seu controle no uso de inseticidas sintéticos pode comprometer a cultura em termos econômicos e ambientais. Como alternativa de controle, o óleo de nim foi aplicado em folhas de tomateiro, avaliando os efeitos inseticida e antialimentar por ação sistêmica e translaminar. No ensaio para avaliar a ação translaminar, o óleo diluído em água foi aplicado na superfície adaxial dos folíolos, em concentrações de 0,5, 1, 5 e 10%. A mortalidade observada variou entre 49 e 100%, e o tamanho médio das minas, entre 1,62 e 0,34 cm. Nos tratamentos representados por água e água + emulsificante (5%), a mortalidade não ultrapassou 20%, com tamanho médio das minas de 1,63 cm. O estudo da ação sistêmica foi realizado ao aplicar o óleo de nim na superfície adaxial e abaxial de todas as folhas das plantas, à exceção daquelas em que as lagartas foram infestadas. Neste ensaio, o óleo foi aplicado nas concentrações de 1, 2,5 e 5%, diluídos em água e emulsificante. Observou-se que a mortalidade foi maior que 90% quando o óleo foi aplicado nas concentrações de 2,5 e 5%, sendo o tamanho médio das minas inferior a 1,0 cm. Não ocorreu mortalidade nos tratamentos controle, mas o tamanho das minas foi, em média, de 1,96 cm. Desta maneira ficou evidenciado que o óleo de nim apresenta efeito inseticida e antialimentar sobre lagartas de T. absoluta, com a propriedade de ser incorporado e translocado através das folhas de tomateiro.(AU)

The leaf miner Tuta absoluta (Meyrick) is the pest that mostly jeopardizes tomato production. The use of synthetic pesticides for its control can affect the crop economically and environmentally. As an alternative form of control, neem oil was applied on tomato leaves in order to assess antifeedant and insecticidal effects by systemic and translaminar action. In experiment for translaminar action, oil diluted in water was applied to the adaxial surface of leaflets at concentrations of 0.5, 1, 5 and 10%. The mortality rate ranged between 49 and 100%, and the average size of the mines, between 1.62 and 0.34 cm. In treatments represented by water and water + emulsifier (5%), mortality did not surpass 20%, with the average size of mines reaching 1.63 cm. The study of systemic action was performed by applying neem oil to the adaxial and abaxial surfaces of all leaves, except those that were infested by caterpillars. In this assay, the oil was applied at concentrations of 1, 2.5 and 5%, being diluted in water and emulsifiers. We observed that the mortality rate exceeded 90% when the oil was applied at concentrations of 2.5 and 5%, and the average size of mines was smaller than 1.0 cm. There was no mortality in the control treatments, but the mine size was on average 1.96 cm. Therefore, it is clear that the neem oil has an insecticidal and anti-food effect on T. absoluta caterpillars, and is possible to be incorporated and applied on tomato leaves.(AU)

The effect of dietary oils on the development of aberrant crypt foci, bifidobacteria and fecal pH.

The present study investigated the relationship between intestinal bifidobacteria and intake of commercial dietary oils of different fatty acids compositions on the development of aberrant crypt foci (ACF). Wistar rats were grouped according to diet and treatment with dimethylhydrazine (DMH): standard diet (CN), canola oil (CAN), olive oil (OLI), corn oil (COR), standard diet and DMH (CNDMH), canola oil and DMH (CANDMH), olive oil and DMH (OLIDMH) and corn oil and DMH (CORDMH). Diets and DMH did not alter the amount of bifidobacteria, fecal pH and serum total cholesterol level. DMH-treated groups had lower serum triglyceride levels compared to respective controls without DMH. Olive and corn oil diets resulted in higher hepatic cholesterol levels than standard diet under treatment with DMH. The numbers of ACF/field and cell proliferation were lower under treatment with CANDMH and OLIDMH, suggesting a protective effect of these oils on colorectal carcinogenesis.

Diet-induced obesity impairs AKT signalling in the retina and causes retinal degeneration.

Retinopathy, a common complication of diabetes, is characterized by an unbalanced production of nitric oxide (NO), a process regulated by nitric oxide synthase (NOS). We hypothesized that retinopathy might stem from changes in the insulin receptor substrate (IRS)/PI3K/AKT pathway and/or expression of NOS isoforms. Thus, we analysed the morphology and apoptosis index in retinas of obese rats in whom insulin resistance had been induced by a high-fat diet (HFD). Immunoblotting analysis revealed that the retinal tissue of HFD rats had lower levels of AKT(1) , eNOS and nNOS protein than those of samples taken from control animals. Furthermore, immunohistochemical analyses indicated higher levels of iNOS and 4-hydroxynonenal and a larger number of apoptotic nuclei in HFD rats. Finally, both the inner and outer retinal layers of HFD rats were thinner than those in their control counterparts. When considered alongside previous results, these patterns suggest two major ways in which HFD might impact animals: direct activity of ingested fatty acids and/or via insulin-resistance-induced changes in intracellular pathways. We discuss these possibilities in further detail and advocate the use of this animal model for further understanding relationships between retinopathy, metabolic syndrome and type 2 diabetes.

Perfil de ácidos graxos na carne de novilhos Charolês e Nelore puros e de gerações avançadas do cruzamento rotativo, terminados em confinamento / Fatty acids profile of feedlot finished purebred Charolais and Nellore steers from advanced generations of rotational crossbreeding

Foram avaliados os efeitos da heterozigose e o grupo genético no perfil de ácidos graxos de novilhos puros (Charolês - C e Nelore - N) e mestiços da segunda (G2) (¾C»N e ¾N»C), da terceira (G3) (5/8C3/8N e 5/8N3/8C) e da quarta (G4) (11/16C5/16N e 11/16N5/16C) geração de cruzamento rotativo. A carne dos novilhos Nelore e dos 11/16N 5/16C apresentou maior proporção de ácido mirístico (C14:0) em relação à carne dos Charolês e dos 11/16C 5/16N. Por outro lado, a carne dos novilhos 11/16C 5/16N apresentou maior presença de ácido heptadecanóico (C17:0) e de ácido araquidônico (C20:4 n6) em relação aos 11/16N 5/16C. Na G2, os novilhos 3/4C 1/4N apresentaram superioridade nos ácidos esteárico (C18:0) e linoléico (C18:2 n6c), na participação total dos ácidos graxos poliinsaturados estudados e na relação entre os ácidos graxos poliinsaturados e saturados, enquanto que os 3/4N 1/4C apresentaram superioridade no ácido oléico (C18:1 n9c). Na G3, as carnes dos novilhos 5/8C 3/8N apresentaram superioridade na participação dos ácidos esteárico e elaídico (C18:1 n9t) e no total dos ácidos graxos saturados, enquanto que os novilhos 5/8N 3/8C apresentaram maior participação dos ácidos miristoléico (C14:1),cis-10-Heptadecanóico (C17:1) e oléico e no total de ácidos graxos insaturados. A heterose foi significativa na G2 para C17:0, C18:0, C18:1 n9c e C18:2 n6c no total dos ácidos graxos saturados, insaturados e poliinsaturados. Novilhos 3/4C 1/4N apresentaram a carne mais saudável entre os grupos genéticos estudados, apresentando carne com maior presença de ácidos graxos poliinsaturados e maior relação poliinsaturados:saturados.

The objective of this research was to evaluate the heterozygosis and genetic group effects on fatty acids profile of feedlot finished steers, straightbreds (Charolais - C and Nellore - N), and crossbreds from second (G2) (¾C »N and ¾N »C), third (G3) (5/8C 3/8N and 5/8N 3/8C) and fourth (G4) (11/16C 5/16N and 11/16N 5/16C) generation of rotational crossbreeding. The Nellore and 11/16N 5/16C meat showed higher proportion of myristic acid (C14:0) in relation to Charolais and 11/16C 5/16N meat, respectively. On the other hand, the meat of the 11/16C 5/16N steers showed higher presence of heptadecanoic acid (C17:0) and arachidonic acid (C20:4 n6) in relation to 11/16N 5/16C. The 3/4C 1/4N steers of G2 which were superior in stearic acid (C18:0) and linoleic acid (C18:2 n6c) in the total polyunsaturated fatty acids participation studied and in the ratio between polyunsaturated and saturated fatty acids, while the 3/4N 1/4C showed superiority in oleic acid (C18:1 n9c). In G3 the meat of the 5/8C 3/8N steers showed superiority in the stearic and elaidic acids (C18:1 n9t) and in the total saturated fatty acid, while the 5/8N 3/8C steers showed higher participation of the meristoleic (C14:1), cis-10-heptadecanoic(C17:1) and oleic acids and total unsaturated fatty acids. The heterosis was significant in the G2 for C17:0, C18:0, C18:1 n9c, C18:2 n6c, in the total saturated, unsaturated and polyunsaturated fatty acids. The 3/4C 1/4N steers showed the healthiest meat among the genetic groups studied, with higher presence of polyunsaturated fatty acids and higher polyunsaturated: saturated ratio.

Ripe fruits of Bromelia antiacantha: investigations on the chemical and bioactivity profile / Quimica e atividade in vitro da banana-do-mato (Bromelia antiacantha Bertol., Bromeliaceae)

Bromelia antiacantha (known as wild banana) is traditionally used to treat coughs, as an emollient and antitussive, and to treat mouth and skin ulcers. To investigate the radical scavenger properties, DPPH and phosphomolybdenium were used, with low antioxidant activity being observed for both (below 5 mg/ml of extract presented no activity for both techniques). An HPLC fingerprint of phenolic compounds was developed and total phenolics through Folin-Ciocalteau method was an average of 500 µg/g of fresh fruits. Any cytotoxicity was observed on L929 fibroblasts cells for aqueous, methanol and lipid extracts between 500 and 0.01 µg/ ml. The wild banana extract (1000 µg/mL) shown a lower genotoxicity when compared to the negative and positive (MMS) controls. Abundant calcium oxalate crystals and sucrose were found and characterized through NMR and X-ray diffraction respectively. Its centesimal composition indicated abundant carbohydrates (45 percent) and lipids (18 percent). The carbohydrate analysis showed acidic monosaccharides, and the lipid analysis shown palmitic and linoleic acids in similar quantities (30 percent each) and oleic acid 20 percent, among others, through GC-FID. The viscosity of the water-soluble polysaccharide sub-fraction (5 g/L) was similar to that of water.

O chá dos frutos maduros de Bromelia antiacantha (banana-de-bugre; banana-do-mato) é usado tradicionalmente para tratar desordens respiratórias, como antitussígeno e também para tratar ulceras de pele e boca. Neste trabalho pesquisou-se o potencial de captação de radicais livres do extrato aquoso e extrato metanólico através da reação de redução do DPPH e do fosfomolibdenio, sendo encontrada baixa atividade nos dois modelos (abaixo de 5 mg/ml nenhuma atividade foi detectada em ambos extratos). Os compostos fenólicos totais foram determinados através de Folin-Ciocalteau, sendo encontrados 500 µg/g de fruto maduro fresco, e foi desenvolvido fingerprint dos compostos fenólicos através de CLAE-DAD. Nenhuma citotoxicidade foi observada em fibroblastos L929 para extratos aquoso, metanólico e lipídico entre 500 e 0,01 µg/ml, assim como baixa genotoxicidade (1000 µg/mL) quando comparados aos controles negativo e positivo (MMS). Abundantes cristais de oxalato de cálcio e de sacarose foram observados e caracterizados por RMN e difração de Raios-X respectivamente, e a composição centesimal do fruto indicou abundantes carboidratos (45 por cento) e lipídeos (18 por cento). A analise de carboidratos encontrou componentes monosacarídicos ácidos e foram encontrados acido palmítico e linoléico em quantidades similares (30 por cento cada) e 20 por cento de acido oléico, entre outros ácidos graxos através de CG-DIC. A viscosidade da sub-fração polissacarídica solúvel em água (5 g/L) foi semelhante a da água.

Isolation of syringaldehyde from Mikania laevigata medicinal extract and its influence on the fatty acid profile of mice / Extrato medicinal de Mikania laevigata: influência no perfil de ácidos graxos em camundongos e isolamento de siringaldeído por CLAE semipreparativa

The Mikania genus is widely known as "guaco" and is used to treat fever, rheumatism, flu and respiratory diseases. Our previous work evidenced the synergism among M. laevigata extract components to produce desirable effects, and included the coumarin precursor, o-coumaric acid as marker. Many Mikania species are producers of ent-kaurene diterpenes which presented antiespasmodic and relaxant activities on smooth muscle. Seeking to standardize the guaco extract, which is registered in the Brazilian Pharmacopoea, this paper deals with the determination of kaurenoic acid through LC-PDA and the isolation through LC of syringaldehyde. Kaurenoic acid was not found in the extract, and syringaldehyde is one of the major compounds of pharmacopoeal extract, together with coumarin and o-coumaric acid. Samples from the lung and liver of Balb-C isogenic allergic pneumonitis bearing mice, treated with the same extract, were analyzed through GC-FID, and the fatty acid content was determined and analyzed. The results obtained by measuring the arachidonic acid (ARA) and docosahexaenoic acid (DHA) in the liver and lung of treated animals demonstrated that the fatty acid composition is distinct in both tissues, and that in the liver, only the DHA was altered as a result of the treatments. DHA is absent in the lung and in both organs, no significant difference in ARA production was observed. The aqueous extract, coumarin and o-coumaric acid stimulated DHA synthesis in the liver (p < 0.05).

O gênero Mikania é popularmente conhecido como "guaco" e é utilizado para tratar febre, reumatismo, resfriados e afecções respiratórias. Em trabalho prévio demonstramos sinergismo entre os componentes do extrato de M. laevigata para produzir os efeitos farmacológicos esperados, incluindo a cumarina e seu precursor ácido o-cumárico como marcadores. Muitas espécies de Mikania são produtoras de diterpenos ent-caurenos que apresentam atividade antispasmódica e relaxante da musculatura lisa. Buscando a padronização do extrato medicinal de guaco (preparado segundo a farmacopéia brasileira 1ª edição), este trabalho visou determinar a presença de ácido caurenóico através de CLAE-DAD e isolou siringaldeído através de CLAE semipreparativa, sendo que o primeiro não foi encontrado no extrato e o siringaldeído é um dos seus componentes majoritários. Camundongos isogênicos Balb-C portadores de pneumonite alérgica foram tratados com este extrato, e amostras de pulmão e fígado foram analisadas por CG-DIC quanto ao seu conteúdo de ácidos graxos. A quantidade de ácido araquidônico (ARA) e de ácido docosahexaenóico (DHA) encontrada demonstrou que a composição é distinta em ambos tecidos, e apenas a concentração de DHA hepático foi alterado em função do tratamento, o qual não foi encontrado no pulmão. Não foi detectada diferença significativa na produção de ARA. Tanto o extrato aquoso, quanto a cumarina e o ácido o-cumárico, estimularam a síntese de DHA no fígado (p < 0.05).

Characterization and potential uses of Copaifera langsdorfii seeds and seed oil.

Copaifera langsdorfii (Desf.) Kuntze (copaiba) seeds are abundantly produced and have not yet been characterized. The seed oil presents a characteristic odor of coumarin (250.1+/-6.57 mg/g determined through LC). The fatty acid composition of the oil was determined through CG/FID, being 45.3% linoleic acid, 32.3% monounsaturated, and 22.4% saturated fat. For the lipid-free seeds, the total carbohydrate, protein and moisture were 75.4%, 6.8% and 14.8%, respectively. The C. langsdorfii xyloglucan had an intrinsic viscosity of 804 mL/g, and the average molar mass (Mw) was 7.82 x 10(5)g/mol and Rg of 65 nm. The degree of polydispersion was 1.7, indicating the polydisperse family of polysaccharides. Its homogeneity, low degree of polymer contaminants and high intrinsic viscosity and molecular mass, represent good potential as a thickening agent. The presence of coumarin and xyloglucan as major components of C. langsdorfii seeds denotes its potential for use in the cosmetic or pharmaceutical industries.

Risk analysis of herbicide quinclorac residues in irrigated rice areas, Santa Catarina, Brazil.

Deterministic and probabilistic risk analyses were carried out for seven hydrographic basins in the State of Santa Catarina (Brazil), where irrigated rice is cultivated. Monitoring studies conducted in 1998/1999 and 1999/2000 had found that the herbicide quinclorac was the most frequently detected agrochemical residue, occurring in five of the seven hydrographic basins. In order to assess the ecological risk posed by quinclorac, median lethal concentration (LC(50)) and median effective concentration (EC(50)) data were obtained for quinclorac in toxicity tests with organisms routinely used in Brazil for this purpose. Experiments were carried out on microcosms associated with the irrigated rice crop to evaluate the effects of the herbicide on the natural plankton community. The deterministic analyses showed that the risk presented by the herbicide residues to the phytoplankton require mitigating action, while the probabilistic analysis revealed that the levels of risk for the aquatic community were acceptable. Field experiments showed that the recommended application concentration of the product directly affects phytoplankton and has an indirect, short-term effect on the zooplankton community.

Perfil de ácidos graxos da gordura intramuscular da carne de vacas de descarte de diferentes grupos genéticos terminadas em confinamento, abatidas com distintos pesos / Fatty acid profile intramuscular fat meat of cull cows from different genetic groups feedlot finished slaughtered with distinct weights

Foi avaliado o perfil dos ácidos graxos da gordura intramuscular do Longissimus dorsi de vacas de descarte mestiças, da segunda (G2 - 3/4Charolês (C) 1/4Nelore (N) e 3/4NC) e da terceira geração (G3 - 5/8CN e 5/8NC) de cruzamento rotativo Charolês - Nelore, terminadas em confinamento e abatidas com 465, 507 ou 566kg. Os animais apresentaram, na média, no início do confinamento, 8,5 anos, 388,6kg e 2,35 pontos de escore da condição corporal. A dieta alimentar, relação volumoso:concentrado de 48:52, continha 12,5 por cento de proteína bruta e 2,99Mcal de energia digestível por kg de matéria seca. Os ácidos graxos saturados C14:0 (merístico) e C16:0 (palmítico) reduziram as suas participações em 19 e 10 por cento, respectivamente, com o aumento do peso de abate de 465 para 566kg, mesmo comportamento observado para o C 18:0 (esteárico). Houve menor representação dos ácidos saturados em detrimento aos insaturados com o incremento do peso de abate, sendo a associação negativa (r=-0,61; P<0,01) entre o marmoreio e a fração de gordura saturada na gordura intramuscular do músculo Longissimus dorsi. A carne das vacas 3/4NC apresentou maior fração dos ácidos graxos palmítico e palmitiléico. Houve redução da participação do ácido graxo pentadecanóico e palmitiléico, e incremento da fração do ácido graxo esteárico da G2 para a G3. O aumento do peso de abate de vacas de descarte propicia um perfil de ácido graxo da gordura intramuscular do Longissimus dorsi benéfico à saúde humana por reduzir a participação de ácidos graxos hipercolesterolêmicos e aumentar os hipocolesterolêmicos. Vacas 3/4 Nelore 1/4 Charolês apresentam maior fração de ácido graxo palmítico e palmitiléico, enquanto que as 5/8 Charolês 3/8 Nelore demonstram maior concentração de esteárico. Animais da terceira geração do cruzamento alternado Charolês - Nelore apresentam carne com menor concentração do ácido graxo palmitiléico e maior de esteárico.

The Longissimus dorsi marbling fatty acid profile of crossbred cull cows, from the second (G2- 3/4Charolais (C) Nellore (N) and 3/4NC) and third (G3 - 5/8CN and 5/8NC) generation of Charolais - Nellore rotational crossbreeding, feedlot finished and slaughtered with 465, 507 and 566 kg were evaluate. At the beginning of the experiment the average age, weight and body condition were, respectively, 8.5 years, 388.6kg and 2.35 points. The diet, with 48:52 roughage:concentrate ratio, contained 12.5 percent crude protein and 2.99Mcal of digestible energy per kg of dry matter. The fatty acids saturated C14:0 (myristic) and C16:0 (palmitic) reduce the his participations in 19 and 10 percent, respectively, with the amplification of the weight of slaughter of 465 about to 566kg, even behavior observer about to the C18:0 (stearic). There was minor representation of the acids saturated detriment insaturad with the increase of the weight of slaughter, being the association negative (r=-0.61; P=.01) among the marbling and the fraction of fat saturated on fat intramuscular of the muscle Longissimus dorsi. The meat from the culls 3/4NC presented major fraction from the fatty acids palmitic and palmitic-oleico. These was reduction of the participation of the fatty acid pentadecanoic and palmitic-oleico, and increase of the fraction of the fatty acid stearic from G2 about to G3. The increase of the weight of culls cows appease a profile of fatty acid from fat intramuscular of the Longissimus dorsi beneficial on the health human reducing the participation of fatty acids hipercolesterolemics and increase the hipocolesterolemics. The culls cows 3/4Charolês 1/4Nelore they presented high fraction of fatty acid palmitic and palmitic-oleico, while the 5/8Charolês 3/8Nelore presented demonstrate high concentration of stearic. Animals from third generation of the Charolais - Nellore rotational crossbreeding, presented meat with low concentration of the fatty acid...

Perfil de ácidos graxos e qualidade da carne de vacas de descarte terminadas em confinamento recebendo dietas com ou sem adição de monensina / Fatty acid profile and meat quality of cull cows feedlot finished receiving diet with or without monensin

Foram avaliados o perfil dos ácidos graxos da gordura intramuscular e a qualidade da carne de vacas de descarte terminadas em confinamento recebendo dietas sem ou com monensina sódica (200mg animal-1 dia-1). A dieta continha 12,5 por cento de proteína bruta e 2,99Mcal de energia digestível kg-1 de matéria seca, composta de 48 por cento de volumoso (silagem de milho) e 52 por cento de concentrado. A presença de monensina não teve efeito significativo sobre a cor, a textura e o marmoreio, apresentando valores médios de 3,55; 3,29 e 6,38 pontos, respectivamente. Quanto às características sensoriais, a carne dos animais alimentados com monensina demonstra ser menos palatável (P<0,10). A inclusão de monensina ocasionou o aumento (P<0,10) da participação de ácidos graxos saturados e a redução dos insaturados na gordura intramuscular do Longissimus dorsi. Entre os ácidos graxos saturados, o uso de monensina aumentou a proporção de heptadecanóico (17:0) e, entre os insaturados, aumentou a proporção do isômero trans (C18:1 n9t) e diminuiu o cis (C18:1 n9c) do oléico. A proporção total de monoinsaturados também reduziu com a inclusão da monensina (P<0,10). A inclusão de monensina diminuiu a qualidade da carne das vacas por diminuir sua palatabilidade. Quanto ao perfil de ácidos graxos totais, a monensina proporciona maior participação de ácidos graxos saturados em detrimento dos insaturados na gordura intramuscular do músculo Longissimus dorsi.

The marbling fatty acid profile and the meat quality of cull cows feedlot finished receiving diets without or with sodic monensin (200mg animal-1 day-1) were evaluated. The diet contained 12.5 percent of crude protein and 2.99 Mcal of digestible energy kg-1 of dry matter, composed of 48 percent of roughage (corn silage) and 52 percent of concentrate. The monensin presence didnÆt have significant effect on the color, texture and marbling, presenting medium values of 3.55, 3.29 and 6.38 points, respectively. Concerning the sensorial characteristics, the meat of the animals fed with monensin it demonstrated to be less palatable (P<.10). The monensin inclusion caused the increase (P<.10) of the participation of saturated fatty acids and reduction of the unsaturated in the fat intramuscular of the Longissimus dorsi. Among the fatty acids saturated, the use of monensin increased heptadecanóico (17:0) proportion and, among the unsaturated group, the trans isomer (C18:1 n9t) increased, and the cis isomer of oleate (C18:1 n9c) decreased (P<.10). The monounsaturated fatty acids proportion was reduced by monensin inclusion (P<.10). Monensin addition decreased the meat quality by decrease its palatability of the meat of cull cows. As regards the profile of fatty acids total, the monensin provides larger participation of saturated fatty acid in detriments to the unsaturated in the fat marbling of the muscle Longissimus dorsi.

Análise de óleos-resinas de copaíba: contribuição para o seu controle de qualidade / Copaiba oil-resin analysis: contribution to quality control

A óleo-resina de copaíba pode ser extraída de forma sustentável do tronco de várias espécies de Copaifera. Ela contém principalmente ácidos resinosos e substâncias voláteis, tendo ampla utilização medicinal. A padronização cromatográfica do óleo é a garantia da identidade desta matéria-prima complexa. Neste trabalho analisaram-se por CG três amostras de óleos de copaíba obtidas de Colombo/PR e doze amostras adquiridas no Estado do Amazonas. O óleo de copaiba foi fracionado por cromatografia em sílica gel impregnada com KOH e metilado e as frações obtidas foram avaliadas por CG. Numa segunda etapa, os óleos brutos metilados por meio de diazometano ou transesterificados com KOH/MeOH foram injetados diretamente em CG. Foram utilizados para comparação os ácidos diterpênicos hardwíckiico, copaiferólico e caurenóico além do sesquiterpeno 14-hidroxi-b-cariofileno (cariofilenol). A presença do ácido copaiferólico foi observada em 100 por cento e cariofilenol em 80 por cento das amostras. Os ácidos caurenóico e hardwíckiico ausentes nas amostras do Paraná, foram detectados em 8,3 por cento e 41,7 por cento respectivamente nas amostras do Amazonas. Os resultados obtidos indicam que podem ser analisados diretamente através de CG após metilação com diazometano, sem necessidade de fracionamento prévio. Adicionalmente, a determinação do índice de acidez para óleos de copaíba não demonstrou resultados inequívocos para as amostras analisadas.

Copaiba oil can be extracted from the trunk of some Copaifera species and contains mainly resinous acids and volatile substances, which have wide medicinal use. The chromatographic standardization of the oil characteristics is the guarantee of the identity of raw material. In this work, three copaiba oil samples from Colombo/PR, and twelve from Amazonas State were analyzed. The copaiba oil was fractionated in silica gel impregnated with KOH, esterified and the fractions were evaluated by TLC and GC. In a second stage, the crude oil was esterified with diazomethane or transesterified with KOH/MeOH and injected in GC. The diterpene acids used for comparison were hardwickiic, copaiferolic and caurenoic and the 14-hydroxy-b-caryophyllene (caryophyllenol). The presence of copaiferolic acid was observed in all analyzed samples and caryophyllenol in 80 percent of the samples. Hardwickiic and caurenoic acids were absent in the samples from Paraná State, and respectively detected in 8.3 percent and 41.7 percent, of the samples from Amazonas. The obtained results indicate that the oil can be directly analyzed through GC after methylation with diazomethane, without previous fractionation. Also, an acidity index method proposed for copaiba oil analysis did not show to be reliable for the analyzed samples.

Perfil de ácidos graxos de cadeia longa e qualidade da carne de novilhos terminados em confinamento com diferentes níveis de monensina sódica na dieta / Long chain fatty acids profile and meat quality of feedlot finished steers with different levels of sodium monensin at the diet

Foi avaliada a composicão química e a qualidade da carne de 48 novilhos das racas Charolês, Nelore e suas cruzas, terminados em confinamento, recebendo à vontade uma dieta com 52 por cento de silagem de milho e 48 por cento de concentrado, adicionada com 0, 100 ou 200mg/dia de monensina sódica, em um delineamento inteiramente casualizado. A dieta apresentou 12,3 por cento de proteína bruta e 58,3 por cento de fibra em detergente neutro. A monensina foi fornecida misturada com o concentrado. A adicão da monensina não alterou o teor de matéria seca, de proteína bruta e de extrato etéreo do músculo Longissimus dorsi dos animais (P>0,05), assim como não influenciou a perda de líquidos durante o descongelamento ou à coccão, a forca de cisalhamento, a maciez, a cor e o marmoreio (P>0,05). No entanto, a palatabilidade e suculência diminuíram linearmente com a inclusão de monensina na dieta (P<0,05). A textura da carne, por sua vez, variou de forma quadrática com o aumento da inclusão de monensina (P<0,05). A inclusão do ionóforo não influenciou a proporcão de ácidos graxos de cadeia longa saturados em relacão aos insaturados (P>0,05), mas aumentou linearmente o teor dos isômeros cis e trans do oleato (C18:1 n9c e C18:1 n9t). Embora tenha aumentado o teor destes ácidos graxos insaturados específicos, a adicão da monensina diminuiu a qualidade da carne dos animais, principalmente por palatabilidade e à suculência.