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Stabilization of linseed oil for use in aquaculture feedsNilson, Stephanie Anne 10 December 2008
An experiment was conducted to determine the effect of addition of antioxidants or encapsulation of linseed oil on the oxidative stability of linseed oil and the effect on growth and fatty acid composition of rainbow trout fed these products. Four diets differing only in their lipid sources were prepared by cold extrusion: 1) fish oil (FO), 2) linseed oil (LO), 3) linseed oil (980 g/kg) stabilized with vitamin E (7.5 g/kg) and butylated hydroxytoluene (BHT) (12.5 g/kg) (stabilized linseed oil; SLO) and 4) linseed oil (350 g/kg) containing vitamin E (7.5 g/kg), BHT (12.5 g/kg) and encapsulated in a coating material primarily consisting of hydrogenated palm oil (630 g/kg) (encapsulated linseed oil; ELO). Diets were fed twice daily to rainbow trout to apparent satiation (n=22 / replicate; 7 replicates per treatment) during a 168 day growth trial. Following the growth trial, the fish were humanely euthanized by a sharp blow to the cranium and analyzed for fatty acid composition, thiobarbituraric reactive substances (TBARS), fillet colour and sensory attributes (trained and consumer panels). There were no significant differences between treatments on any of the growth parameters investigated or TBARS levels of fish fillets. Omega-3 polyunsaturated fatty acids of trout fed LO were significantly higher than those fed FO (35.5% of total fatty acids vs. 27.6%) and ELO (28.9%) (P < 0.05). EPA and DHA levels were not significantly different between treatments. Diet samples were stored for 168 days at room temperature in sealed plastic containers. Following storage, the oxidative stability index (OSI) of the FO and LO diets were reduced to 0.00 hours while that of the SLO diet 9.20 hours and the ELO diet was 11.40 hours. Trained panelists determined fish fed FO had a significantly higher aroma intensity and significantly lower aroma desirability and overall acceptability than those fed SLO. The rancid aroma and flavour of the FO-fed fish was significantly higher than fish fed the other treatments (P < 0.05). Consumer panelists found no significant differences between the sensory attributes of fish fed the four experimental diets and exhibited no preference between treatments (P > 0.05). Fillets from fish fed FO had significantly higher values than the other three treatments for redness (3.59 vs values between 1.86 and 2.07) and yellowness (25.35 vs values between 20.51 and 21.22) (P < 0.05). Addition of antioxidants to linseed oil improves its oxidative stability during storage and processing and results in fish fillets with fatty acid composition and consumer acceptance equal or superior to fish fed fish oil.
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Stabilization of linseed oil for use in aquaculture feedsJanuary 2008 (has links)
An experiment was conducted to determine the effect of addition of antioxidants or encapsulation of linseed oil on the oxidative stability of linseed oil and the effect on growth and fatty acid composition of rainbow trout fed these products. Four diets differing only in their lipid sources were prepared by cold extrusion: 1) fish oil (FO), 2) linseed oil (LO), 3) linseed oil (980 g/kg) stabilized with vitamin E (7.5 g/kg) and butylated hydroxytoluene (BHT) (12.5 g/kg) (stabilized linseed oil; SLO) and 4) linseed oil (350 g/kg) containing vitamin E (7.5 g/kg), BHT (12.5 g/kg) and encapsulated in a coating material primarily consisting of hydrogenated palm oil (630 g/kg) (encapsulated linseed oil; ELO). Diets were fed twice daily to rainbow trout to apparent satiation (n=22 / replicate; 7 replicates per treatment) during a 168 day growth trial. Following the growth trial, the fish were humanely euthanized by a sharp blow to the cranium and analyzed for fatty acid composition, thiobarbituraric reactive substances (TBARS), fillet colour and sensory attributes (trained and consumer panels). There were no significant differences between treatments on any of the growth parameters investigated or TBARS levels of fish fillets. Omega-3 polyunsaturated fatty acids of trout fed LO were significantly higher than those fed FO (35.5% of total fatty acids vs. 27.6%) and ELO (28.9%) (P < 0.05). EPA and DHA levels were not significantly different between treatments. Diet samples were stored for 168 days at room temperature in sealed plastic containers. Following storage, the oxidative stability index (OSI) of the FO and LO diets were reduced to 0.00 hours while that of the SLO diet 9.20 hours and the ELO diet was 11.40 hours. Trained panelists determined fish fed FO had a significantly higher aroma intensity and significantly lower aroma desirability and overall acceptability than those fed SLO. The rancid aroma and flavour of the FO-fed fish was significantly higher than fish fed the other treatments (P < 0.05). Consumer panelists found no significant differences between the sensory attributes of fish fed the four experimental diets and exhibited no preference between treatments (P > 0.05). Fillets from fish fed FO had significantly higher values than the other three treatments for redness (3.59 vs values between 1.86 and 2.07) and yellowness (25.35 vs values between 20.51 and 21.22) (P < 0.05). Addition of antioxidants to linseed oil improves its oxidative stability during storage and processing and results in fish fillets with fatty acid composition and consumer acceptance equal or superior to fish fed fish oil.
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Stabilization of linseed oil for use in aquaculture feedsNilson, Stephanie Anne 10 December 2008 (has links)
An experiment was conducted to determine the effect of addition of antioxidants or encapsulation of linseed oil on the oxidative stability of linseed oil and the effect on growth and fatty acid composition of rainbow trout fed these products. Four diets differing only in their lipid sources were prepared by cold extrusion: 1) fish oil (FO), 2) linseed oil (LO), 3) linseed oil (980 g/kg) stabilized with vitamin E (7.5 g/kg) and butylated hydroxytoluene (BHT) (12.5 g/kg) (stabilized linseed oil; SLO) and 4) linseed oil (350 g/kg) containing vitamin E (7.5 g/kg), BHT (12.5 g/kg) and encapsulated in a coating material primarily consisting of hydrogenated palm oil (630 g/kg) (encapsulated linseed oil; ELO). Diets were fed twice daily to rainbow trout to apparent satiation (n=22 / replicate; 7 replicates per treatment) during a 168 day growth trial. Following the growth trial, the fish were humanely euthanized by a sharp blow to the cranium and analyzed for fatty acid composition, thiobarbituraric reactive substances (TBARS), fillet colour and sensory attributes (trained and consumer panels). There were no significant differences between treatments on any of the growth parameters investigated or TBARS levels of fish fillets. Omega-3 polyunsaturated fatty acids of trout fed LO were significantly higher than those fed FO (35.5% of total fatty acids vs. 27.6%) and ELO (28.9%) (P < 0.05). EPA and DHA levels were not significantly different between treatments. Diet samples were stored for 168 days at room temperature in sealed plastic containers. Following storage, the oxidative stability index (OSI) of the FO and LO diets were reduced to 0.00 hours while that of the SLO diet 9.20 hours and the ELO diet was 11.40 hours. Trained panelists determined fish fed FO had a significantly higher aroma intensity and significantly lower aroma desirability and overall acceptability than those fed SLO. The rancid aroma and flavour of the FO-fed fish was significantly higher than fish fed the other treatments (P < 0.05). Consumer panelists found no significant differences between the sensory attributes of fish fed the four experimental diets and exhibited no preference between treatments (P > 0.05). Fillets from fish fed FO had significantly higher values than the other three treatments for redness (3.59 vs values between 1.86 and 2.07) and yellowness (25.35 vs values between 20.51 and 21.22) (P < 0.05). Addition of antioxidants to linseed oil improves its oxidative stability during storage and processing and results in fish fillets with fatty acid composition and consumer acceptance equal or superior to fish fed fish oil.
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The effect of exogenous DIM on Brassica napus and its role in response to heavy metal stressRoode, Enrico Carlo January 2017 (has links)
Magister Scientiae - MSc (Biotechnology) / Brassica napus is a plant that is used for human and animal consumption.
This plant is also used for phytoremediation due to its relatively higher level
of heavy metal tolerance. In South Africa, mining is one of the main drivers
of the economy. One of the major negative environmental impacts of mining
is heavy metal contamination. Soil metal content can rise to levels that are
quite high and can even have a negative impact on the yields of B. napus
crop. The glucosinolate-myrosinase system of B. napus is a system that is
used as defence against biotic stressors. Indole glucosinolate breakdown
products have been proven to enhance the antioxidant capacity of plants.
Some have also shown growth promoting properties in plants.
We studied the effect of exogenous DIM on B. napus and it role in Zr
induced heavy metal stress. Germination percentages revealed that DIM
increased germination, Zr application decreased germination and the DIMZr
treatment reversed the negative impact of Zr application on B. napus.
The effect of treatments on the biomass of B. napus was assessed by
determining the dry weights. Results show that exogenous DIM improves
biomass. Zr application decreased biomass and DIM-Zr treatment
ameliorated the effect of Zr application. / 2020-08-31
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Controlled Release of Antioxidants via Biodegradable Polymer Films into Milk and Dry Milk Productsvan Aardt, Marleen 08 December 2003 (has links)
Residual value is defined as the price for which a used piece of equipment can be sold in the market at a particular time. It is an important element of the owning costs of equipment and needs to be estimated by equipment managers for making investment decisions.
The purpose of this study is to gain insights into the residual value of selected groups of heavy construction equipment and to develop a mathematical model for its prediction. Auction sales data were collected from two online databases. Manufacturer publications and an online source provided size parameters and manufacturers suggested retail prices matching the auction records. Macroeconomic indicator values were collected from a variety of sources, including government agencies. The data were brought into the same electronic format and were matched by model name and calendar date, respectively.
Data from auctions in the U.S. and in Canada were considered for this study. Equipment from four principal manufacturers of up to 15 years of age at the time of sale was included. A total of 35,542 entries were grouped into 11 different equipment types and 28 categories by size as measured by horse power, standard operating weight, or bucket volume. Equipment types considered were track and wheel excavators, wheel and track loaders, backhoe loaders, integrated toolcarriers, rigid frame and articulated trucks, track dozers, motor graders, and wheel tractor scrapers.
Multiple linear regression analyses of the 28 datasets were carried out after outliers had been deleted. Explanatory variables for the regression model were age in years, the indicator variables manufacturer, condition rating, and geographic region, and selected macroeconomic indicators. The response variable was residual value percent, defined as auction price divided by manufacturers suggested retail price. Different first, second, and third-order polynomial models and exponential and logarithmic models of age were examined. A second-order polynomial was selected from these functional forms based on the adjusted coefficient of determination. Coefficients for the 28 models and related statistics were tabulated. A spreadsheet tool incorporating the final regression model and its coefficients was developed. It allows performing the residual value prediction in an interactive and intuitive manner. / Ph. D.
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Relevância do fibroblasto no remodelamento parenquimatoso pulmonar em modelos experimentais de fibrose induzida por bleomicina e 3-5-di-tert-4-hidroxitolueno / Relevance of fibroblasts in lung parenchymal remodeling in experimental models of bleomycin and 3-5-di-tert-4-hydroxytoluene-induced fibrosisSilva, Vanessa Martins da 23 September 2015 (has links)
A remodelação do epitélio e do mesênquima subjacente tem um papel crucial na patogênese da fibrose pulmonar experimental. A iniciação, gravidade e distribuição de fibrose varia entre os diferentes agentes químicos. Estudos recentes indicaram que o envolvimento epitelial, a expressão de proteínas reguladoras do epitélio, ativação endotelial, estresse do retículo endoplasmático, a ativação de fibroblastos e acumulação de diferentes tipos de colágeno, pode ser específica em lesão causadas por diferentes agentes químicos. Neste estudo, comparou-se a fibrose pulmonar induzida por bleomicina (BLM) e hidroxitolueno butilado (BHT). Envolvimento epitelial, proteínas reguladoras, ativação endotelial e de fibroblastos foram quantitativamente avaliados pela densidade de células alveolares, expressão de telomerase, endotelina-1 (ET-1), fator de crescimento vascular (VEGF), fator de transformação do crescimento beta (TGF-beta) e do fator de crescimento de fibroblastos básico (bFGF). Estresse celular em células epiteliais alveolares do tipo 2 (AEC II) e fibroblastos, eventualmente, responsáveis pela gênese da fibrose pulmonar, foram investigados por microscopia eletrônica. Os colágenos do tipo I (Col I), III (Col III) e V (Col V) foram caracterizados e quantificados por imunofluorescência. A quantidade de colágeno pulmonar e alterações histológicas fibróticas foram significativamente aumentadas nos grupos BLM e BHT em relação aos controles, com diferença significativa entre a resposta fibrótica precoce e tardia. A densidade AEC II, a expressão da telomerase, ET-1, VEGF, TGF-beta e bFGF foram significativamente maiores nos grupos BLM e BHT do que em pulmões dos grupos controles, com diferença significativa entre a fase precoce e tardia da resposta fibrótica. Mitocôndrias anormais e estresse do retículo endoplasmático em AEC II e fibroblastos foram encontrados em ambos os grupos fibróticos. Aumento no acumulo de fibras de Col I, III e V, foram encontradas no interstício pulmonar após instilação de BLM e BHT. A expressão gênica de TGF-beta1 e alfa actina de músculo liso (alfa-SMA) foi significativamente maior em ambos modelos de fibrose pulmonar. Ativação de Smad3 (Mothers against decapentaplegic homolog 3) associada à expressão de IL-beta1 (Interleucina-1 beta), Lox (lisil-oxidase) e o fator de transcrição Sp1 (Specificity protein 1) foi associada com a ativação do gene alfa-SMA. Em conclusão, os nossos resultados tornam-se relevantes pois demonstram que, independentemente do insulto inicial, há uma convergência no perfil de sinalização, onde fica evidente que a lesão epitélio/endotelial está envolvida num amplo e contínuo processo de reparação com consequente final fibrótico. Um elemento chave no reparo e remodelamento tecidual ou fibrose é a resposta mesenquimal que fornece componentes essenciais de MEC necessários para a infraestrutura da cura e por outro lado para a fibrose progressiva crônica / Epithelial and underlying mesenchyme remodeling have a critical role in the pathogenesis of experimental pulmonary fibrosis. The initiation, distribution and severity of fibrosis varies among different chemical agents. Recent studies have indicated that epithelial involvement, expression of epithelial regulatory proteins, endothelium activation, endoplasmic reticulum stress, fibroblast activation and accumulation of different types of collagen may be specific in various chemical agents of injury. In this study, bleomycin (BLM) and Butylated hydroxytoluene (BHT)-induced pulmonary fibrosis in mice were compared. Epithelial involvement, regulatory proteins, endothelium and fibroblast activation were quantitatively evaluated by alveolar cells density, telomerase, endothelin-1 (ET-1), Vascular endothelial growth factor (VEGF), Transforming growth factor beta (TGF-beta) and basic fibroblast growth factor (bFGF) expression. Cellular stress in type 2 alveolar epithelial cells (AEC II) and fibroblasts, eventually responsible by generating lung fibrosis, were investigated by electron microscopy. We characterized and quantified collagen type I (Col I), III (Col III) and V (Col V) by immunofluorescence. Lung collagen content and fibrotic histological changes were significantly increased in BLM and BHT models compared to control with significant difference between early and late fibrotic response. AEC II density, telomerase expression, ET-1, VEGF, TGF-beta and bFGF were significantly higher than control lungs with significant difference between early and late BLM and BHT fibrotic response. Abnormal mitochondria and endoplasmic reticulum in AEC II and fibroblasts was found in both groups of chemical agents. Increased of Col I, Col III and V fibers accumulation was found in the lung interstitium after BLM and BHT instillation. The expression of TGF-beta1 and alfa smooth muscle actin (alfa-SMA) gene was significantly increased in both model of pulmonary fibrosis. Activated Smad3 (Mothers against decapentaplegic homolog 3) associated to the IL-beta1 (Interleukin-1 beta), Lox (Lysyl oxidase) and the transcription factor Sp1 (Specificity protein 1) was associated to the activation of alfa-SMA gene. In conclusion, our results become relevant because they demonstrate that, regardless of the initial insult, there is a convergence in the signaling profile, where it is clear that the epithelial/endothelial injury is involved in a broad and continuous repair process with consequent fibrotic end. A key component in tissue repair and remodeling, or fibrosis is the mesenchymal response which provides essential components of extracellular matrix infrastructure needed to cure and secondly for chronic progressive fibrosis
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Relevância do fibroblasto no remodelamento parenquimatoso pulmonar em modelos experimentais de fibrose induzida por bleomicina e 3-5-di-tert-4-hidroxitolueno / Relevance of fibroblasts in lung parenchymal remodeling in experimental models of bleomycin and 3-5-di-tert-4-hydroxytoluene-induced fibrosisVanessa Martins da Silva 23 September 2015 (has links)
A remodelação do epitélio e do mesênquima subjacente tem um papel crucial na patogênese da fibrose pulmonar experimental. A iniciação, gravidade e distribuição de fibrose varia entre os diferentes agentes químicos. Estudos recentes indicaram que o envolvimento epitelial, a expressão de proteínas reguladoras do epitélio, ativação endotelial, estresse do retículo endoplasmático, a ativação de fibroblastos e acumulação de diferentes tipos de colágeno, pode ser específica em lesão causadas por diferentes agentes químicos. Neste estudo, comparou-se a fibrose pulmonar induzida por bleomicina (BLM) e hidroxitolueno butilado (BHT). Envolvimento epitelial, proteínas reguladoras, ativação endotelial e de fibroblastos foram quantitativamente avaliados pela densidade de células alveolares, expressão de telomerase, endotelina-1 (ET-1), fator de crescimento vascular (VEGF), fator de transformação do crescimento beta (TGF-beta) e do fator de crescimento de fibroblastos básico (bFGF). Estresse celular em células epiteliais alveolares do tipo 2 (AEC II) e fibroblastos, eventualmente, responsáveis pela gênese da fibrose pulmonar, foram investigados por microscopia eletrônica. Os colágenos do tipo I (Col I), III (Col III) e V (Col V) foram caracterizados e quantificados por imunofluorescência. A quantidade de colágeno pulmonar e alterações histológicas fibróticas foram significativamente aumentadas nos grupos BLM e BHT em relação aos controles, com diferença significativa entre a resposta fibrótica precoce e tardia. A densidade AEC II, a expressão da telomerase, ET-1, VEGF, TGF-beta e bFGF foram significativamente maiores nos grupos BLM e BHT do que em pulmões dos grupos controles, com diferença significativa entre a fase precoce e tardia da resposta fibrótica. Mitocôndrias anormais e estresse do retículo endoplasmático em AEC II e fibroblastos foram encontrados em ambos os grupos fibróticos. Aumento no acumulo de fibras de Col I, III e V, foram encontradas no interstício pulmonar após instilação de BLM e BHT. A expressão gênica de TGF-beta1 e alfa actina de músculo liso (alfa-SMA) foi significativamente maior em ambos modelos de fibrose pulmonar. Ativação de Smad3 (Mothers against decapentaplegic homolog 3) associada à expressão de IL-beta1 (Interleucina-1 beta), Lox (lisil-oxidase) e o fator de transcrição Sp1 (Specificity protein 1) foi associada com a ativação do gene alfa-SMA. Em conclusão, os nossos resultados tornam-se relevantes pois demonstram que, independentemente do insulto inicial, há uma convergência no perfil de sinalização, onde fica evidente que a lesão epitélio/endotelial está envolvida num amplo e contínuo processo de reparação com consequente final fibrótico. Um elemento chave no reparo e remodelamento tecidual ou fibrose é a resposta mesenquimal que fornece componentes essenciais de MEC necessários para a infraestrutura da cura e por outro lado para a fibrose progressiva crônica / Epithelial and underlying mesenchyme remodeling have a critical role in the pathogenesis of experimental pulmonary fibrosis. The initiation, distribution and severity of fibrosis varies among different chemical agents. Recent studies have indicated that epithelial involvement, expression of epithelial regulatory proteins, endothelium activation, endoplasmic reticulum stress, fibroblast activation and accumulation of different types of collagen may be specific in various chemical agents of injury. In this study, bleomycin (BLM) and Butylated hydroxytoluene (BHT)-induced pulmonary fibrosis in mice were compared. Epithelial involvement, regulatory proteins, endothelium and fibroblast activation were quantitatively evaluated by alveolar cells density, telomerase, endothelin-1 (ET-1), Vascular endothelial growth factor (VEGF), Transforming growth factor beta (TGF-beta) and basic fibroblast growth factor (bFGF) expression. Cellular stress in type 2 alveolar epithelial cells (AEC II) and fibroblasts, eventually responsible by generating lung fibrosis, were investigated by electron microscopy. We characterized and quantified collagen type I (Col I), III (Col III) and V (Col V) by immunofluorescence. Lung collagen content and fibrotic histological changes were significantly increased in BLM and BHT models compared to control with significant difference between early and late fibrotic response. AEC II density, telomerase expression, ET-1, VEGF, TGF-beta and bFGF were significantly higher than control lungs with significant difference between early and late BLM and BHT fibrotic response. Abnormal mitochondria and endoplasmic reticulum in AEC II and fibroblasts was found in both groups of chemical agents. Increased of Col I, Col III and V fibers accumulation was found in the lung interstitium after BLM and BHT instillation. The expression of TGF-beta1 and alfa smooth muscle actin (alfa-SMA) gene was significantly increased in both model of pulmonary fibrosis. Activated Smad3 (Mothers against decapentaplegic homolog 3) associated to the IL-beta1 (Interleukin-1 beta), Lox (Lysyl oxidase) and the transcription factor Sp1 (Specificity protein 1) was associated to the activation of alfa-SMA gene. In conclusion, our results become relevant because they demonstrate that, regardless of the initial insult, there is a convergence in the signaling profile, where it is clear that the epithelial/endothelial injury is involved in a broad and continuous repair process with consequent fibrotic end. A key component in tissue repair and remodeling, or fibrosis is the mesenchymal response which provides essential components of extracellular matrix infrastructure needed to cure and secondly for chronic progressive fibrosis
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