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1.
Heliyon ; 10(10): e31506, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38818199

RESUMO

Neo-formed contaminants (NFCs) are common in many foods, especially those subjected to high-temperature processing. Among these contaminants, products arising from the Maillard reaction, sugar reduction, thermal degradation of polyphenols and lipid oxidation, including acrylamide, furan, furfuryl alcohol, and hydroxymethylfurfural, are consistently linked to potential neoplastic effects. NFCs are found in globally traded commodities like coffee and cocoa, posing a significant risk due to their frequent consumption by consumers. A direct correlation exists between consumption frequency, exposure levels, and health risks. Hence, it's crucial to establish reliable methods to determine levels in both matrices, aiming to mitigate their formation and minimise risks to consumers. This review offers a comprehensive examination, discussion, and identification of emerging trends and opportunities to enhance existing methodologies for extracting and quantifying NFCs in coffee and cocoa. By presenting an in-depth analysis of performance parameters, we aim to guide the selection of optimal extraction techniques for quantifying individual NFCs. Based on the reviewed data, headspace extraction is recommended for furan, while solid and dispersive solid phase extractions are preferred for acrylamide when quantified using gas and liquid chromatography, respectively. However, it is worth noting that the reported linearity tests for certain methods did not confirm the absence of matrix effects unless developed through standard addition, leading to uncertainties in the reported values. There is a need for further research to verify method parameters, especially for determining NFCs like furfuryl alcohol. Additionally, optimising extraction and separation methods is essential to ensure complete compound depletion from samples. Ideally, developed methods should offer comprehensive NFC determination, reduce analysis time and solvent use, and adhere to validation parameters. This review discusses current methods for extracting and quantifying NFCs in coffee and cocoa, highlighting emerging trends and emphasising the need to improve existing techniques, especially for compounds like furfuryl alcohol.

2.
Acta sci., Biol. sci ; 44: e58571, mar. 2022. tab
Artigo em Inglês | VETINDEX | ID: biblio-1370276

RESUMO

The current study evaluates the antiparasitic effect of thymol on reducing parasite burden, especially Cryptosporidium load, in poultry drinking water and in improving zootechnical performances of chicks. The first experiment assessed in vitro the anti-cryptosporidiumactivity of NP (thymol-based product) on drinking water samples using microscopic counting. Samples were treated by increasing concentrations of thymol (1, 2 and 4 g L-1of NP). In vivo, chicken wererandomly assigned to three groups (control and chicks consuming treated water with two concentration of thymol (1 and 2 g L-1of NP). Water treatment efficiency was evaluated on the intestinal parasitic load and zootechnical performances of animals (Body weight, body weight gain, food intake and the consumption index). In vitro the anti-cryptosporidium effect was dose dependent (p <0.05; p <0.01; p <0.001). The in vivo test showed that the intestinal parasitic load was significantly lower (p <0.05; p <0.01; p <0.001) in the group treated with 2 g L-1of NP. Additionally, results showed a significant increase (p <0.05; p <0.1; p <0.001) in the body weight and the body weight gain of treated groups during the whole rearing period compared to the control. Furthermore, treated groups represent a lower consumption index compared to the control.(AU)


Assuntos
Animais , Água Potável , Peso Corporal , Cryptosporidium , Ingestão de Líquidos , Antiparasitários , Técnicas In Vitro
3.
Braz. arch. biol. technol ; Braz. arch. biol. technol;64: e21200100, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153289

RESUMO

HIGHLIGHTS Comparative study of the operation of eight real cases of systems installed in Paraná. There is a convergence between the values estimated by the Atlas and the ones calculated. It was possible to identify the cities that presented the greatest figures of merit.


Abstract With the development of renewable energies in the world, there is also an increase in solar photovoltaic systems globally. In Brazil, and in the state of Paraná, there is an exponential growth of this form of energy generation, which causes the necessity to study the performance of the installed systems. Therefore, this article analyzed eight photovoltaic systems installed in the state of Paraná, under the aspect of figures of merit parameters, through calculations of final yield, performance ratio and capacity factor. In addition, the calculated values were compared to the values estimated by the Solar Energy Atlas of the State of Paraná. As a result, the largest average differences in final yield, between the calculations and the Atlas, were found in the cities of Cascavel, while the smallest were observed in Goioerê.


Assuntos
Humanos , Energia Solar/estatística & dados numéricos , Energia Fotovoltaica/métodos , Brasil , Consumo de Energia/estatística & dados numéricos , Energia Fotovoltaica/estatística & dados numéricos , Modelos Teóricos
4.
Rev. bras. ciênc. avic ; 22(3): eRBCA, out. 2020. tab
Artigo em Inglês | VETINDEX | ID: biblio-1490787

RESUMO

The objective of this study was to evaluate the effects of supra-nutritional level of selected B vitamins in different types of diet on broiler performance. Two experiments were conducted using male and female one-day-old chicks (n=288 each; initial body weights in experiment I and II was, respectively, 47.57 ± 0.43, and 47.98 ± 0.31) reared in batteries up to 18 days. In experiment I, the chicks were fed a corn and soybean meal-based diet and, in experiment II, a diet containing oxidized animal by-product meals and soybean oil was used. Both experiments followed a completely randomized design in a 3 × 2 factorial arrangement, consisting of the factors: i) supplementation levels of selected B vitamins (control, 3- or 6-times control of the vitamins riboflavin, pantothenic acid, niacin, folic acid and vitamin B12); ii) dietary nutritional density (low or high), totaling 6 treatments and 8 replicates of 6 birds each (3 males and 3 females). As result of this study, in Exp. I, chicks showed higher weight gain (741.1 g vs. 697.3 g) and feed intake (920.2 vs. 878.5 g) when fed low-nutritional density diet with supra-nutritional vitamin level 6-times higher than the control. However, this effect was not found in the performance of chickens fed high-nutritional density diet. Despite the poor quality of the ingredients used in Exp. II, no statistical effect was shown of the use of vitamin super-dose in rations with different dietary nutrient density. Feed conversion ratio (FCR) was significantly improved for chickens fed high-nutritional density diet (1.191 vs. 1.246 in experiment I, 1.244 vs. 1.275 in experiment II, p 0.01). We conclude that birds fed a vegetable diet formulated with low-dietary density improved body weight (BW) and feed intake (FI) when receiving supra-nutritional levels of vitamins 6-times higher than the control.


Assuntos
Animais , Complexo Vitamínico B/análise , Complexo Vitamínico B/biossíntese , Galinhas/fisiologia , Galinhas/metabolismo , Ração Animal/análise
5.
R. bras. Ci. avíc. ; 22(3): eRBCA-2019-1024, out. 2020. tab
Artigo em Inglês | VETINDEX | ID: vti-761961

RESUMO

The objective of this study was to evaluate the effects of supra-nutritional level of selected B vitamins in different types of diet on broiler performance. Two experiments were conducted using male and female one-day-old chicks (n=288 each; initial body weights in experiment I and II was, respectively, 47.57 ± 0.43, and 47.98 ± 0.31) reared in batteries up to 18 days. In experiment I, the chicks were fed a corn and soybean meal-based diet and, in experiment II, a diet containing oxidized animal by-product meals and soybean oil was used. Both experiments followed a completely randomized design in a 3 × 2 factorial arrangement, consisting of the factors: i) supplementation levels of selected B vitamins (control, 3- or 6-times control of the vitamins riboflavin, pantothenic acid, niacin, folic acid and vitamin B12); ii) dietary nutritional density (low or high), totaling 6 treatments and 8 replicates of 6 birds each (3 males and 3 females). As result of this study, in Exp. I, chicks showed higher weight gain (741.1 g vs. 697.3 g) and feed intake (920.2 vs. 878.5 g) when fed low-nutritional density diet with supra-nutritional vitamin level 6-times higher than the control. However, this effect was not found in the performance of chickens fed high-nutritional density diet. Despite the poor quality of the ingredients used in Exp. II, no statistical effect was shown of the use of vitamin super-dose in rations with different dietary nutrient density. Feed conversion ratio (FCR) was significantly improved for chickens fed high-nutritional density diet (1.191 vs. 1.246 in experiment I, 1.244 vs. 1.275 in experiment II, p 0.01). We conclude that birds fed a vegetable diet formulated with low-dietary density improved body weight (BW) and feed intake (FI) when receiving supra-nutritional levels of vitamins 6-times higher than the control.(AU)


Assuntos
Animais , Galinhas/metabolismo , Galinhas/fisiologia , Complexo Vitamínico B/análise , Complexo Vitamínico B/biossíntese , Ração Animal/análise
6.
Chirality ; 31(8): 583-591, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31185131

RESUMO

Praziquantel (PZQ) composes a regular medicine available in a tablet form to fight schistosomiasis and just half of its mass is composed by the active principle (L-PZQ), the other half, D-PZQ, is frequently associated to a strong bitter taste. Moreover, optically pure L-PZQ derivatives could be used in studies about adult and juvenile worms' resistance. Nowadays, these studies use racemic PZQ (rac-PZQ) as starting point. The D-PZQ, which would be discarded, could be racemized, coming back as feed concentration in the process. The present work aims to get L-PZQ and D-PZQ with high optical purities (more than 97%) and productivity (more than 253 g kgads -1  day-1 ) towards semipreparative scale for researches involving L-PZQ, L-PZQ derivatives, and D-PZQ racemization. In order to achieve this goal, a built-in-house simulated moving bed chromatographic unit with the cellulose tris (3-chloro-4-methylphenylcarbamate) (Chiralcel OZ) as chiral stationary phase (CSP) was used to investigate different scenarios of separation according to a well-known design method called triangle theory. In all scenarios investigated, at least one of the outlet streams presented high optically purity for one of the enantiomers. Comparison with literature showed superior performance of our unit even at racemic mixture concentrations that were 10 times lower than the racemic concentrations found in literature.

7.
Rev. MVZ Córdoba ; 24(1): 7127-7136, ene-abr. 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1013272

RESUMO

ABSTRACT Objective. Investigate the effects of L-carnitine as a potential means of reducing the incidence of ascites in broilers and its relationship with physiological and biochemical paramaters. Material and methods. One-day-old 300 male broiler chicks (Ross 308) were used in the trial. The group without L-carnitine supplementation (0) was assigned as control and the groups that received 100, 150, 200 and 250 mg/L L-carnitine supplementation in water were assigned as treatment groups. The trial was completed in 35 days. Results. L-carnitine supplementation did not have any significant effect on live weight gain, feed consumption, water consumption and feed conversion ratio. Levels of blood plasma and hemogram parameters HDL, Triglyceride, CK, RBC and MCH were significantly affected by L-carnitine (p<0.05). Blood gas parameter pH value was significantly affected by L-carnitine supplementation in the broilers with ascites. Blood gas pH value significantly increased with 100 mg/L L-carnitine supplementation compared to that of control (p<0.05). While blood pH was 7.21 in the animals with ascites, it was determined as 7.48 in healthy animals. Concentrations of SO2 and ctO2 were higher in healthy animals, while ctCO2P and hemoglobin concentrations were higher in ascitic animals (p<0.05). Conclusions. Ascites mortality rates starting from the control group were calculated respectively as %; 20.00, 18.33, 26.67, 28.33 and 28.33%. 76.71% of total ascites deaths were in the 5th week. It was concluded that low doses of L-carnitine supplementation may have positive effects in the broilers grown at high altitude.


RESUMEN Objetivo. Investigar los efectos de la L-carnitina como un medio potencial para reducir la incidencia de ascitis en pollos de engorde y su relación con parámetros fisiológicos y bioquímicos. Material y métodos. Se utilizaron 300 pollos de engorde machos de un día de edad (Ross 308) en el ensayo. El grupo sin suplementación de L-carnitina (0) se asignó como control y los grupos que recibieron suplementos de 100, 150, 200 y 250 mg/L de L-carnitina en agua se asignaron como grupos de tratamiento. La prueba se completó en 35 días. Resultados. La suplementación de L-carnitina no tuvo ningún efecto significativo sobre el aumento de peso vivo, consumo de alimento, consumo de agua y tasa de conversión alimenticia. Los niveles de plasma sanguíneo y los parámetros del hemograma HDL, triglicéridos, CK RBC y MCH se vieron afectados significativamente por L-carnitina (p<0.05). El valor del pH del parámetro del gas en sangre se vio significativamente afectado por la suplementación con L-carnitina en los pollos de engorde con ascitis. El valor del pH del gas en la sangre aumentó significativamente con la suplementación de 100 mg/L de L-carnitina en comparación con la del control (p<0.05). Mientras que el pH de la sangre fue de 7.21 en los animales con ascitis, se determinó como 7.48 en animales sanos. Las concentraciones de SO2 y ctO2 fueron mayores en animales sanos, mientras que las concentraciones de ctCO2P y hemoglobina fueron mayores en animales ascíticos (p<0.05). Conclusiones. Las tasas de mortalidad por ascitis a partir del grupo control se calcularon respectivamente como %; 20.00, 18.33, 26.67 y 28.33. 76.71% de las muertes totales de ascitis fueron en la quinta semana. Se concluyó que dosis bajas de suplementos de L-carnitina pueden tener efectos positivos en los pollos de engorde criados a gran altitude.


Assuntos
Animais , Ascite , Galinhas , Hipertensão Pulmonar , Acetilcarnitina
8.
Braz. arch. biol. technol ; Braz. arch. biol. technol;61(spe): e18000210, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-974141

RESUMO

ABSTRACT Considering the development of new technologies in the electricity generation sector, such as solar photovoltaic energy, some studies are made necessary to obtain the best performance of these systems. This generation model consists of modules, which are exposed to adverse climatic conditions, they receive direct influence of the dirt, according to the environment from which they were installed, which directly influences the performance of the system since, due to the disposal of waste on the module, a smaller portion of the solar radiation can reach the photovoltaic cell effectively. The objective of this work is to determine the ideal time for cleaning photovoltaic panels, aiming at high system productivity, having as object of study the photovoltaic panels of the Federal University of Technology - Paraná (UTFPR) Campus Curitiba, installed in the Green Office (GO) and at Neoville´s headquarters. Within this objective, it was necessary to verify its merit indexes, parameters used to compare grid-connected photovoltaic systems. The study shows the importance of frequent cleaning of panels, especially when they are installed in urban areas and close to high traffic access roads.


Assuntos
Energia Solar , Energia Fotovoltaica , Brasil , Eficiência , Zeladoria
9.
Braz. arch. biol. technol ; Braz. arch. biol. technol;61(spe): e18000230, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-974137

RESUMO

ABSTRACT The increase in energy demand in Brazil encourages the country to increasingly invest in generation of electric energy, where the demand for other renewable sources increases gradually because they have a lower impact on the environment. The use of Grid-Connected Photovoltaic Systems (GCPVS) is a viable solution for the country, since it presents favorable natural conditions for the use of solar energy. This study approaches the current scenario of three photovoltaic systems installed in Curitiba in 2016 and part of 2017: Green Office (GO) located in Curitiba Campus Downtown, Curitiba Campus Neoville, both of the Federal Technological University of Paraná (UTFPR), as well as a residence. By means of performance parameters, performance analysis of these systems were carried out and, in order to measure the length of time of the return of the initial investment in its installation, a study of the economic viability of these systems according to the current rate model in Brazil through economic engineering tools was carried out: Simple Payback and Discounted Payback, Net Present Value and Internal Rate of Return. Finally, the application of the saved value of electric energy bills was simulated in a bank account during the system´s lifespan.


Assuntos
Abastecimento de Energia/economia , Energia Fotovoltaica/economia , Estudos de Viabilidade , Eficiência
10.
Bioprocess Biosyst Eng ; 38(11): 2063-75, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26227509

RESUMO

Global variables play a key role in evaluation of the performance of pneumatic bioreactors and provide criteria to assist in system selection and design. The purpose of this work was to use experimental data and computational fluid dynamics (CFD) simulations to determine the global performance parameters gas holdup ([Formula: see text]) and volumetric oxygen transfer coefficient (k L a), and conduct an analysis of liquid circulation velocity, for three different geometries of pneumatic bioreactors: bubble column, concentric-tube airlift, and split tube airlift. All the systems had 5 L working volumes and two Newtonian fluids of different viscosities were used in the experiments: distilled water and 10 cP glycerol solution. Considering the high oxygen demand in certain types of aerobic fermentations, the assays were carried out at high flow rates. In the present study, the performances of three pneumatic bioreactors with different geometries and operating with two different Newtonian fluids were compared. A new CFD modeling procedure was implemented, and the simulation results were compared with the experimental data. The findings indicated that the concentric-tube airlift design was the best choice in terms of both gas holdup and volumetric oxygen transfer coefficient. The CFD results for gas holdup were consistent with the experimental data, and indicated that k L a was strongly influenced by bubble diameter and shape.


Assuntos
Reatores Biológicos , Simulação por Computador , Glicerol/química , Modelos Químicos , Água/química
11.
Anal Chim Acta ; 830: 11-22, 2014 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-24856507

RESUMO

The lack of well-established references for the validation of qualitative analyses and the increasing demand for reliable binary responses were the main motivating factors for this study. A detailed procedure for single-laboratory validation of qualitative methods is proposed. The experimental design and the tools for data analysis were based on the theoretical background, as well as the aspects of efficiency, convenience and simplicity. Four experimental steps were defined, as follows: (i) preliminary tests for the determination of the concentration range, (ii) a study of the rates, unreliability region, detection limit, and the accordance and concordance values, (iii) a study of the selectivity in the presence of known interferences, and (iv) a study of robustness. The applicability of the procedure was demonstrated by the validation of a qualitative commercial kit for detecting sulfonamide residues in raw milk using both the visual and instrumental reading techniques. Reliability rates of 100% were obtained for the blank samples. For the samples spiked with sulfamethazine at 10.8 and 108 µg L(-1) and with sulfadimethoxine or sulfathiazole at 10 and 100 µg L(-1), the reliability rates ranged from 93.3 to 100%. Selectivity was demonstrated using trimethoprim as a potential interferent. The method was considered robust for the factors of the temperature (54 and 58°C) and time (6 and 10 min) for incubating the test strips. The estimated detection limits and unreliability regions confirmed the suitability of the kit for this purpose, based on the legislated residue limits.


Assuntos
Leite/química , Sulfonamidas/análise , Animais , Reprodutibilidade dos Testes
12.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1489821

RESUMO

This study included 35 farmers contracted by a broiler integrator company. Each farmer owned an average of seven poultry houses, housing six flocks per year per farmer, summing up 4.0 million broilers housed. Live performance was evaluated in flocks housed in three densities (D1 12, 12 D2 14, and D3>14 birds/m2), and included the following parameters: market age (MA), average flock weight (AFW), average daily gain (DWG), feed conversion ratio (FCR), livability (LB), production efficiency index (PEI) and carcass yield/m2 (CY). Production costs and gross margin were calculated with birds housed at two densities (11.5 D4 12.4 and 14.5 D5 15.5birds/m2), standardizing MA to 44 days. The economic evaluation included 15 farmers and 1.0 million broilers housed. The average densities obtained for D1, D2, D3, D4, and D5 were 11.80, 13.15, 15.00, 12.02, and 14.98 birds/m2, respectively. Density effect was significant on most parameters, with D1 producing the best results in AFW, DWG, FCR, LB, and PEI, whereas D2 and D3 produced different results only in FCR. Despite the reduction in animal performance, carcass yield/m2 linearly increased with density. The economic analyses showed higher production costs, despite the higher margin for D5. The greatest impact was the reduction in farmer's compensation (19.68%) per bird housed. From the farmer's perspective, the 5% increase in compensation should be enough to cover the investment required to supply the requirements of higher densities.

13.
Artigo em Inglês | VETINDEX | ID: vti-717837

RESUMO

This study included 35 farmers contracted by a broiler integrator company. Each farmer owned an average of seven poultry houses, housing six flocks per year per farmer, summing up 4.0 million broilers housed. Live performance was evaluated in flocks housed in three densities (D1 12, 12 D2 14, and D3>14 birds/m2), and included the following parameters: market age (MA), average flock weight (AFW), average daily gain (DWG), feed conversion ratio (FCR), livability (LB), production efficiency index (PEI) and carcass yield/m2 (CY). Production costs and gross margin were calculated with birds housed at two densities (11.5 D4 12.4 and 14.5 D5 15.5birds/m2), standardizing MA to 44 days. The economic evaluation included 15 farmers and 1.0 million broilers housed. The average densities obtained for D1, D2, D3, D4, and D5 were 11.80, 13.15, 15.00, 12.02, and 14.98 birds/m2, respectively. Density effect was significant on most parameters, with D1 producing the best results in AFW, DWG, FCR, LB, and PEI, whereas D2 and D3 produced different results only in FCR. Despite the reduction in animal performance, carcass yield/m2 linearly increased with density. The economic analyses showed higher production costs, despite the higher margin for D5. The greatest impact was the reduction in farmer's compensation (19.68%) per bird housed. From the farmer's perspective, the 5% increase in compensation should be enough to cover the investment required to supply the requirements of higher densities.

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