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In this paper, a miniaturized biosensor containing 96 silicon microchambers electroloaded with nano-volumes of liquid (EW-chip) is presented. The liquid electroloading is achieved by the appropriate modulation of interface properties. The surface chemistries have been studied to guarantee effective interface properties for both electrowetting on dielectric actuation and biocompatibility versus biochemical reactions. The silicon microchambers are 200 nl in volume and are connected to a specific system of electrodes able to deliver liquid sample on each well. The device also integrates temperature sensors and heaters to perform biochemical reactions. On that, the effectiveness of this device has been successfully proven towards the nucleic acids detection via real-time polymerase chain reaction amplification. Hepatitis B virus genome target has been used to assess the device performance. Results show very uniform amplification over the 96 microchambers without any cross-contamination process. These features make this system a very appealing potential solution for genetic point-of-care devices where a high level of parallelism of analysis is required.

This study aims to develop certain perspectives based on the principle of on-site remediation of the soil through biological means known as "bioremediation" against soil pollution issues resulting from fuel contamination in our country and to reveal the fatty acid profile in the final soils. The fatty acid profile of the soils was pointed out by testing the activity of three basic bioremediation applications (biological multiplication, biological excitation and the combined application of these two approaches) established in the laboratory condition. Under biological multiplication applications, six of the selected bacterial strains (Pseudomons aeruginosa, Pseudomonas putida biotype A, Citrobacter amalonaticus-GC subgroup A, Acinetobacter genomospecies) exhibit the highest growth in crude oil environment isolated from oil-contaminated soils of Adana, Batman and Adıyaman, and they also have the highest levels of crude oil degradation. Under biological excitation applications, the organic materials being humic-fulvic acid and, in combined applications, different combinations of bacteria mixture and organic materials were examined as to the amount of crude oil they degrade in an incubation period of 120 days by qualitative hydrocarbon-type analyses. The highest level of oil degradation, being 56%, occurred under biological multiplication applications where the bacteria mixture was applied. Under biological excitation conditions where various organic materials were applied to the contaminated soil, degradation to 18% was observed. In combined applications, oil degradation was achieved to 30%. The most common fatty acids were found to be 15:0 iso, 15:0 anteiso, 16:0, 16:1 w7c, 17:0ai, 18:2w6,9 and 18:1w9c fatty acids detected in both unpolluted and oil-contaminated soils. Determination of high level 18:1w9c fatty acid in oil contaminated and clean soils may indicate the presence of Pseudomonas spp. However, fatty acid 15:0 anteiso was determined to be higher in oil-contaminated soils than in unpolluted soils. It may be explained that Gram positive bacteria were predominant in oil-contaminated environment.Key words: Soil, crude oil, bacteria, bioremediation, phospholipid fatty acids analysis-fatty acid methyl ester (PLFA-FAME).

The quantification of fatty acids (FA) in meat products is frequently carried out by two-stage methylation procedures followed by long gas chromatography (GC) runs. This work aimed to simplify this methodology by means of a one-stage transmethylation method and a fast GC run, evaluating the influence of sample preparation, reagents and type of heating on the amount of FA in different meat products and optimizing a fast GC-FID (flame ionization detector) run. This allowed to establish the optimum combination of parameters (methanol + chlorotrimethylsilane, lyophilized samples and oven heating) to achieve the quantification of the highest possible amount of FA and to reduce the time of GC run from 60 to 10 min. The quality evaluation of this method obtained satisfactory results. Thus, the quantification of FA in meat products was achieved in a straightforwardly and quickly way by using a one-stage transmethylation procedure followed by a fast GC-FID run.

Masne kiseline su kemijski spojevi građeni od ugljikovodičnog lanca i karboksilne skupine. Masnoće biljnog i životinjskog podrijetla su izvor masnih kiselina u ljudskoj prehrani. Pomoću plinske kromatografije i analizom metilnih estera masnih kiselina uspješno su određeni profili masnih kiselina iz različitih vrsta biljnih ulja te u maslu i maslacu. Usporedbom udjela pojedinih masnih kiselina u ispitivanim uzorcima, ovisno o stupnju zasićenosti te udjelu esencijalnih masnih kiselina, predložene su najkvalitetnije masnoće u prehrani s niskim udjelom ugljikohidrata te pojačanim unosom masti (LCHF)., Fatty acids are chemical compounds made of a hydrocarbon chain and a carboxyl group. Fats of plant and animal origin are a source of fatty acids in the human diet. With the help of gas chromatography and analysis of fatty acid methyl esters, fatty acid profiles from different types of vegetable oils and in butter oil and butter were successfully determined. By comparing the content of individual fatty acids in the tested samples, depending on the degree of saturation and the content of essential fatty acids, the highest quality fats were proposed in the diet with a low carbohydrate content and increased fat intake (LCHF).

Orientador: Prof. Dr. Luiz Fernando de Lima Luz Jr. Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia Química. Defesa : Curitiba, 28/01/2021 Inclui referências: p. 79-86 Resumo: A crescente demanda por biodiesel é altamente importante e necessária, uma vez que os combustíveis provindos do petróleo não são ambientalmente favoráveis, podem ter flutuações de preço e não são renováveis. Embora o preço do diesel no Brasil seja 14% mais barato que o preço médio mundial, ele ainda é mais caro que nos Estados Unidos, Bolívia e Rússia, por exemplo, alcançando apenas o 57° lugar no ranking de preço do diesel (Neder, 2019). Além disso, verificou-se que, recentemente, a gasolina vendida no Brasil era a segunda mais cara do mundo, onde o primeiro lugar pertencia ao Reino Unido (Fontes, 2018). Por esses motivos, os mercados que utilizam combustíveis renováveis estão sendo constantemente estudados e aprimorados para poder entrar no mercado de maneira competitiva. Observando a situação no Brasil, a maioria das indústrias produtoras de biodiesel está na região centro-oeste, que detém 39% da capacidade instalada do país, seguida pela região sul, com 38%. Levando em consideração as várias questões sobre sustentabilidade, meio ambiente e economia de combustível, a ênfase crescente no biodiesel é notória. Essa importância pode ser percebida pelos incentivos ao seu uso no diesel, como na aprovação pela ANP para aumentar de 11 para 12% a mistura de biodiesel no diesel a partir de março de 2020, e com a intenção de aumentar esse valor nos próximos anos. Com uma demanda constante por combustíveis alternativos e ecológicos, o biodiesel aparece como uma boa opção de uso. Embora o biodiesel seja obtido a partir de óleos vegetais ou gordura animal, outra fonte está se tornando muito promissora na indústria; o uso de óleo residual. Como essa nova fonte geralmente inclui uma quantidade considerável de ácidos graxos livres (AGLs), o processo de produção de biodiesel deve ser adaptado para atingir as especificações necessárias. Neste trabalho, diferentes condições de reação de esterificação, como tipo de óleo, temperatura (50 a 70°C), concentração de catalisador (0,33% a 0,66% em relação à massa reacional), razão etanol/água (7:3 a 9:1) e a razão etanol/ácido (1:1 a 12:1) foram variadas para analisar a melhor condição a ser definida e, com os dados, encontrar os parâmetros corretos para a cinética da reação. A equação regredida foi obtida utilizando todos os pontos experimentais, a exceção do conjunto com razão etanol/água de 7:3 e quatro experimentos com razão etanol/água de 9:1, sendo utilizadas posteriormente para validação dos parâmetros regredidos. Uma vez definida a equação da cinética, ela foi inserida na cinética de reação no Aspen Plus® e a simulação do processo foi construída. Portanto, o processo consiste na reação de esterificação e transesterificação, juntamente com o processo de purificação do biodiesel. Com o mesmo software, também foi possível analisar possíveis economias de energia adicionando trocadores de calor de integração energética em comum quando a razão etanol/água na primeira coluna de destilação para reciclo de etanol variasse entre 7:3, 8:2 e 9:1. Por fim, foi feita a análise econômica do processo completo e a melhor razão etanol/água para a corrente de reciclo e make-up, bem como o melhor tempo de residência do reator de esterificação para otimização do processo foram escolhidos. Considerando a produção de biodiesel desejada, a avaliação econômica pôde ser realizada e o tempo de retorno do investimento foi calculado. Palavras-chave: Biodiesel, óleo ácido, ácidos graxos, esterificação e transesterificação, simulação de processo Abstract: The increasing demand for biodiesel is highly important and necessary, as petroleum fuels are not environmentally friendly, may have price fluctuations, and are not renewable. Even though Brazil's diesel price is 14% cheaper than the world's average price, it is still more expensive than United States, Bolivia, and Russia, for example, achieving only 57th place in the ranking of diesel price (Neder, 2019). It was also found that recently, gasoline sold in Brazil was the second most expensive in the world, where the first place belonged to the United Kingdom (Fontes, 2018). For these reasons, markets using renewable fuels are being continually studied and refined to enter the market competitively. Looking at Brazil's situation, most biodiesel-producing industries are in the midwest region, which holds 39% of the country's installed capacity, followed by the southern region, with 38%. Regarding several questions about sustainability, environment, and fuel economy, biodiesel's growing emphasis is notorious. This importance can be seen through the incentives for its use in diesel, as it was approved by the ANP to increase from 11 to 12% the biodiesel blend in diesel from March 2020 and with the intention to increase that value in the upcoming years. With a constant demand for alternative, environmentally friendly fuels, biodiesel shows up as the right choice for use instead of the petroleum-based ones. Even though biodiesel is obtained from vegetable oils or animal fat, another source is becoming very promising in the industry; the use of waste oil. As this new source usually includes a considerable amount of free fatty acids (FFAs), biodiesel production process must be adapted to achieve the necessary specifications. In this present work, different esterification reaction conditions, as oil type, temperature (50°C to 70°C), catalyst concentration (0.33 %wt to 0.66 %wt of total reaction mass), ethanol/water ratio (7:3 to 9:1), and ethanol/acid ratio (1:1 to 12:1) were varied to analyze the best condition set and, with the data, find the correct parameters for the reaction kinetics. The equation was then regressed and all the experimental points were used except for the ethanol/water ratio of 7:3 and four experiments with an ethanol/water ratio of 9:1, as it was further used for validation of the regressed parameters. Once the kinetics equation was defined, it was inserted on Aspen Plus® reaction kinetics, and the process simulation was built. Therefore, the process consists of the esterification and transesterification reaction, along with the biodiesel purification process. With the same Software, it was also possible to analyze potential energy savings by adding heat exchangers in common when the ethanol/water ratio on the first ethanol recycling distillation column corresponded to 7:3, 8:2, and 9:1. At last, the full process economic analysis was made, and the best ethanol/water ratio for both the recycle and make-up streams, as well as the best esterification reactor residence time for process optimization, were chosen. Considering the desired biodiesel production, the economic evaluation could be fulfilled, and the payout time was calculated. Keywords: Biodiesel, acid oil, fatty acids, esterification and transesterification, simulation design

Introduction: Cachexia is a critical issue in patients with refractory heart failure (HF). Although the elevation of resting energy expenditure (REE) can progress cachexia through relatively insufficient calorie intake, the detail of REE in HF patients remains uncertain and no useful marker for predicting insufficient calorie intake has been established. This study aimed to assess the REE of HF patients and to evaluate the detectability of serum and urine laboratory markers for insufficient calorie intake. Methods: We measured REE using indirect calorimetry in 69 HF patients (NYHA class II-IV) in our hospital. In 25 out of 69 patients, serum albumin, amino acids, and 24-hour urine amino acids were measured. The calorie intake insufficiency was determined based on measured REE multiplied by activity index Results: As compared to the predicted values by Harris-Benedict equation, 43 patients (63%) had an elevated REE and the mean REE was approximately 4% elevated. There was no significant correlation between the REE and parameters indicating HF severity, including cardiac index on right heart catheterization and BNP level. Only body mass index (BMI) negatively correlated with the REE (r=-0,66, p Conclusions: Our findings suggest that the patients with refractory HF, especially having low BMI, are likely to be under inadequate calorie intake due to elevated REE. The calorie intake insufficiency could not be identified with serum levels of albumin nor essential amino acids. Instead, urine essential amino acids would decrease first prior to plasma levels, indicating this measurement would be a useful marker to detect calorie intake insufficiency.

Biochemical diagnosis of hereditary metabolic diseases requires the detection and simultaneous identification of a large number of compounds, hence the interest in metabolic profiles. Organic acid chromatography allows the identification of several hundred compounds and the quantification of the main molecules of interest. As part of the accreditation process for medical biology examinations according to standard NF EN ISO 15189, the group from the French society for inborn errors of metabolism (SFEIM) recommends an approach to accredit organic acid chromatography. Validation parameters and recommendations are discussed in this specific framework.

The analysis of urinary organic acids is useful for patients suspected to have inborn errors of metabolism known as organic acidurias. These diseases cause an accumulation of organic acids in body fluids and their abnormal excretion in urines. By means of chemometrics tools, such as principal component analysis and multiple linear regression, it was concluded that the conditions used in our laboratory are really the most suitable to achieve high yields of analytes.

Bioactive omega-3 polyunsaturated fatty acids have been shown to reduce the risk of death in patients with cardiovascular disease and alleviate the symptoms of other inflammatory diseases. However, the mechanisms of action of these effects remain unclear. It has been postulated that omega-3 polyunsaturated fatty acids modify cell membranes by incorporation into the membrane and altering the signaling properties of cellular receptors. In this chapter, we explore the effects of omega-3 polyunsaturated fatty acids on cell membrane structure and function. We present a review of the current evidence for the health benefits of these compounds and explore the molecular mechanisms through which omega-3 polyunsaturated fatty acids interact with membrane lipids and modulate bilayer structure. Using computational models of multicomponent phospholipid bilayers, we assess the consequences of incorporation of these fatty acids on membrane lipid packing, water permeation, and membrane structure.

Fat and fatty acids (FAs) are important quality parameters of dairy foods, characterizing their nutritional value. Efficient routine analyses of their contents are of critical importance for dairy farms and factories. Conventional methods for determining fat and FAs contents of dairy foods are time-consuming, laborious, destructive to samples and often requiring use of hazard solvents, which make it impossible for real-time and on-line measurements. Spectroscopic techniques based on near-infrared spectroscopy (NIRS), Raman spectroscopy (RS), nuclear magnetic resonance (NMR) have been studied extensively for fat and FAs analyses of dairy foods, and promising results have been shown. In this context, this paper summarized the current research progress in application of the three important techniques in predicting fat content and FAs composition of dairy products such as milk, milk powder and cheese. First, the working principles and features of these techniques were described, and then the research advances of each technique for fat and FAs analyses of the dairy foods are presented in detail and the factors influencing their modeling results are discussed. Perspectives on their current situation, future trends and challenges are also discussed.