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1.
Foods ; 13(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38611325

RESUMO

A significant fraction of the food produced worldwide is currently lost or wasted throughout the supply chain, squandering natural and economic resources. Food waste valorization will be an important necessity in the coming years. This work investigates the ability of food waste to serve as a viable nutritional substrate for the heterotrophic growth of Chlorella vulgaris. The impact of different pretreatments on the elemental composition and microbial contamination of seven retail food waste mixtures was evaluated. Among the pretreatment methods applied to the food waste formulations, autoclaving was able to eliminate all microbial contamination and increase the availability of reducing sugars by 30%. Ohmic heating was also able to eliminate most of the contaminations in the food wastes in shorter time periods than autoclave. However, it has reduced the availability of reducing sugars, making it less preferable for microalgae heterotrophic cultivation. The direct utilization of food waste containing essential nutrients from fruits, vegetables, dairy and bakery products, and meat on the heterotrophic growth of microalgae allowed a biomass concentration of 2.2 × 108 cells·mL-1, being the culture able to consume more than 42% of the reducing sugars present in the substrate, thus demonstrating the economic and environmental potential of these wastes.

2.
J Enzyme Inhib Med Chem ; 39(1): 2330907, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38651823

RESUMO

Antimicrobial resistance (AMR) is a pressing global issue exacerbated by the abuse of antibiotics and the formation of bacterial biofilms, which cause up to 80% of human bacterial infections. This study presents a computational strategy to address AMR by developing three novel quantitative structure-activity relationship (QSAR) models based on molecular topology to identify potential anti-biofilm and antibacterial agents. The models aim to determine the chemo-topological pattern of Gram (+) antibacterial, Gram (-) antibacterial, and biofilm formation inhibition activity. The models were applied to the virtual screening of a commercial chemical database, resulting in the selection of 58 compounds. Subsequent in vitro assays showed that three of these compounds exhibited the most promising antibacterial activity, with potential applications in enhancing food and medical device safety.


Assuntos
Antibacterianos , Biofilmes , Desenho de Fármacos , Testes de Sensibilidade Microbiana , Relação Quantitativa Estrutura-Atividade , Biofilmes/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Estrutura Molecular , Humanos , Contaminação de Alimentos/prevenção & controle , Relação Dose-Resposta a Droga
3.
Front Psychol ; 15: 1374784, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38533209

RESUMO

Introduction: Considering the importance of assessing the impacts resulting from a sport career, this study aimed at developing and validating a semi-structure interview guide suitable for quantifying the sociodemographic and epidemiological profile of former professional football players. Methods: Based on the theoretical frameworks and several methodological procedures, an interview guide was developed, consisting of 3 areas of conceptual organization (A1. Biographical data; A2. Professional Career; and A3. Post-Career Transition) and 8 data collection categories (C1. Personal data; C2. Professional data; C3. Sociodemographic background; C4. Epidemiological pathway; C5. Moment of career retirement (career transition); C6. Post-career sociodemographic pathway; C7. Post-career epidemiological pathway; and C8. Perceptions of post-career planning). Thus, in procedural terms, four stages were considered for the construction and validation of the interview guide, namely the Ad hoc construction of the interview guide (i), the review of the in-terview guide by a panel of experts (ii), definition of procedures and protocol for the application of the interview (iii), and the application of the pilot study for the face validation of the interview guide (iv). The sample consisted of two former Portuguese professional players. Results and discussion: To analyze and discuss the data, a content analysis was carried out on all the answers given to each question in the script by the interviewees. From them, matrices were created with the response references to each subcategory. In this way, it was possible to analyse the type of answers given by the interviewees and relate them to the theoretical perspectives of the topic being investigated. The results showed that the interview guide for the study of the impacts of the sports careers on the quality of life of Portuguese former football players shows reliability for the collection of qualitative and quantitative information from the respective content analysis. The use of the interview guide characterizes the path of former player, providing information and knowledge on the sociodemographic and epidemiological impact factors resulting from their post-career.

4.
Food Res Int ; 181: 114112, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38448111

RESUMO

The incorporation of nanostructures loaded with bioactive compounds into food matrices is a promising approach to develop new functional foods with improved nutritional, health profiles and good sensorial properties. The rheological and tribological properties of yogurt enriched with curcumin-loaded solid lipid nanoparticles (SLN) were evaluated. Also, the TCA solubility index, the bioaccessibility of curcumin and cell viability were assessed after dynamic in vitro digestion. The presence of SLN in yogurt did not affect its rheological properties; however, SLN addition increased the lubrication capability of yogurt. After in vitro digestion, yogurt with added SLN (yogurt_SLN) presented a lower TCA solubility index (22 %) than the plain yogurt (39 %). The bioaccessibility and stability of curcumin were statistically similar for yogurt_SLN (30 % and 42 %, respectively) and SLN alone (20 % and 39 %, respectively). Regarding cell viability results, the intestinal digesta filtrates of both controls (i.e., SLN alone and plain yogurt) did not affect significantly the cell viability, while the yogurt_SLN presented a possible cytotoxic effect at the concentrations tested. In general, the incorporation of SLN into yogurt seemed to promote the mouthfeel of the yogurt and did not adversely affect the bioaccessibility of curcumin. However, the interaction of SLN and yogurt matrix seemed to have a cytotoxic effect after in vitro digestion, which should be further investigated. Despite that, SLN has a high potential to be used as nanostructure in a functional food as a strategy to increase the bioactive compounds' bioaccessibility.


Assuntos
Curcumina , Lipossomos , Nanopartículas , Curcumina/farmacologia , Iogurte , Alimento Funcional , Digestão
5.
Molecules ; 29(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38474634

RESUMO

The inclusion of protein in the regular human diet is important for the prevention of several chronic diseases. In the search for novel alternative protein sources, plant-based proteins are widely explored from a sustainable and ecological point of view. Duckweed (Lemna minor), also known as water lentil, is an aquatic plant with potential applications for human consumption due to its protein content and carbohydrate contents. Among all the conventional and novel protein extraction methods, the utilization of ultrasound has attracted the attention of scientists because of its effects on improving protein extraction and its functionalities. In this work, a Box-Behnken experimental design was proposed to optimize the alkaline extraction of protein from duckweed. In addition, an exploration of the effects of ultrasound on the morphological, structural, and functional properties of the extracted protein was also addressed. The optimal extraction parameters were a pH of 11.5 and an ultrasound amplitude and processing time of 60% and 20 min, respectively. These process conditions doubled the protein content extracted in comparison to the value from the initial duckweed sample. Furthermore, the application of ultrasound during the extraction of protein generated changes in the FTIR spectra, color, and structure of the duckweed protein, which resulted in improvements in its solubility, emulsifying properties, and foaming capacity.


Assuntos
Araceae , Poluentes Químicos da Água , Humanos , Poluentes Químicos da Água/análise , Água/metabolismo
6.
Foods ; 13(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38397554

RESUMO

Electric field-based technologies offer interesting perspectives which include controlled heat dissipation (via the ohmic heating effect) and the influence of electrical variables (e.g., electroporation). These factors collectively provide an opportunity to modify the functional and technological properties of numerous food proteins, including ones from emergent plant- and microbial-based sources. Currently, numerous scientific studies are underway, contributing to the emerging body of knowledge about the effects on protein properties. In this review, "Electric Field Processing" acknowledges the broader range of technologies that fall under the umbrella of using the direct passage of electrical current in food material, giving particular focus to the ones that are industrially implemented. The structural and biological effects of electric field processing (thermal and non-thermal) on protein fractions from various sources will be addressed. For a more comprehensive contextualization of the significance of these effects, both conventional and alternative protein sources, along with their respective ingredients, will be introduced initially.

7.
Oral Radiol ; 40(2): 295-303, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38302684

RESUMO

OBJECTIVES: To determine pre-operative cleft volume and evaluate cleft´s impact on surrounding anatomical structures in children and adolescents with orofacial clefts using cone bean computed tomography (CBCT) imaging. METHODS: The present retrospective study retrieved CBCT examinations of 68 patients from a previous study. The examinations had been exposed either before (n = 53) or after (n = 15) alveolar bone grafting. Pre-operative volume of cleft was determined, and type and location were evaluated. Morphological changes on the adjacent anatomical structures, including the incisive foramen, the nasal septum and floor, and the inferior turbinate, were assessed. RESULTS: Mean bilateral cleft volume was 0.76 cm3, while mean unilateral cleft volume was 1.08 cm3; the difference was significant (p < 0.001). Variation in cleft volume, however, was large. The incisive foramen was not visible in the majority of cases with bilateral clefts (71%); the difference was significant (p = 0.001). In cases with unilateral clefts, the nasal septum in 87% was curved towards the cleft or graft side. Also, the mean size of the widest part of the inferior turbinate was 8.8 mm on the cleft or graft side and 10.4 mm on the non-cleft side. The difference was significant (p < 0.001). CONCLUSIONS: When required, CBCT is a feasible method for quantitatively illustrating alveolar clefts and their impact on the morphological development of surrounding structures. Variation in cleft volume was large.


Assuntos
Fenda Labial , Fissura Palatina , Tomografia Computadorizada de Feixe Cônico Espiral , Criança , Adolescente , Humanos , Fissura Palatina/diagnóstico por imagem , Fenda Labial/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada de Feixe Cônico/métodos
8.
Food Chem ; 441: 138295, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38183719

RESUMO

This study evaluated the physicochemical characteristics of nanostructured lipid carriers (NLCs) as a potential vehicle for cannabidiol (CBD), a lipophilic molecule with great potential to promote health benefits. NLCs were produced using hemp seed oil and fully-hydrogenated soybean oil at different proportions. The emulsifiers evaluated were soybean lecithin (SL), Tween 80 (T80) and a mixture of SL:T80 (50:50). CBD was tested in the form of CBD-rich extract or isolate CBD, to verify if it affects the NLCs characteristics. Based on particle size and polydispersity, SL was considered the most suitable emulsifier to produce the NLCs. All lipid proportions evaluated had no remarkable effect on the physicochemical characteristics of NLCs, resulting in CBD-loaded NLCs with particle size below 250 nm, high CBD entrapment efficiency and CBD retention rate of 100% for 30 days, demonstrating that NLCs are a suitable vehicle for both CBD-rich extract or isolate CBD.


Assuntos
Canabidiol , Nanopartículas , Nanoestruturas , Nanopartículas/química , Portadores de Fármacos/química , Promoção da Saúde , Nanoestruturas/química , Óleo de Soja , Emulsificantes/química , Tamanho da Partícula , Polissorbatos
9.
Cuad. psicol. deporte ; 24(1): 257-274, Ene 2, 2024. tab, graf
Artigo em Inglês | IBECS | ID: ibc-229631

RESUMO

La observación sistemática es un método que permite obtener numerosas informaciones sobre el comportamiento del entrenador, incluida la comunicación, que es parte integral del proceso de eficacia pedagógica. Tras revisar varios sistemas de observación y comprobar su potencial, pero principalmente sus debilidades, surge el Sistema de Análisis de Información del Entrenador de Fútbol en Competición (SAITFC) desde una perspectiva de evolución y aportación científica. Un sistema flexible que incluye dimensiones, categorías y subcategorías, que hacen referencia a la información en un intento de hacer inclusivos todos los comportamientos relacionados con la información emitida por el entrenador, ayudando a elaborar un perfil de comportamiento en competición. El cálculo de los porcentajes de concordancia, complementando con las estadísticas Kappa de Cohen, mostró altos niveles de fidelidad de las observaciones para ser utilizadas como herramienta científica. Con este estudio piloto, los resultados obtenidos en esta investigación sugieren que los entrenadores emiten cada vez más información, no solo a los atletas, en forma de instrucción y feedback, sino a todos los agentes deportivos involucrados en la competencia, es decir, el arbitraje, el oponente y el equipo técnico en forma de conversaciones. El feedback tiende a ser prescriptive, auditive, dirigido al atleta, táctico y afectivamente neutral. Es importante destacar la expresividad de los feedbacks relacionados con esquemas tácticos y velocidad de reacción. El SAITFC, como herramienta para ayudar a sistematizar el comportamiento del entrenador, demostró ser un método eficaz, contribuyendo así a la formación de los entrenadores, pero también a nivel científico, ayudándolos en el campo.(AU)


Systematic observation is a method that allows obtaining numerous information about the coach ́s behavior, including communication, whichis an integral part of the process of pedagogical effectiveness. After reviewing several observation systems and verifying their potential, mainly their weaknesses, the Information Analysis System for Football Coaches in Competition (SAITFC) emerges from a perspective of evolution andscientific contribution. A flexible system that includes dimensions, categories, and subcategories, which refer to the information in an attempt to make all behaviors related to the information issued by the coach inclusive, helping to elaborate a behavioral profile in the competition. The calculation of agreement percentages, complemented by Cohen ́s Kappa statistics, showed substantial levels of reliability for the observations to be used as a scientific tool. With this pilotstudy, the results obtainedin this investigation suggest that coaches issue more and more information, not only to athletes, in the form of instruction and feedback but to all sports agents involved in the competition, namely arbitration, opponent, and technical team in the form of conversations. Feedback tends to be prescriptive, auditory, addressed to the athlete, tactical, and effectively neutral. It is essential to emphasize the expressiveness of the feedback related to tactical schemes and reaction speed. The SAITFC, as a tool tohelp systematize the coach ́s behavior, proved to be an effective method, thus contributing tothe training of coaches, but also at a scientific level, helping them in the field.(AU)


A observação sistemática é um método que permite obter inúmeras informações sobre o comportamento do treinador, entre elas a comunicação, a qual é parte integrante do processo de eficácia pedagógica.Após revisão de vários sistemas de observação e constatação das suas potencialidades, mas principalmente das suas fragilidades, surge assim numa perspetiva de evolução e de contributo científico, o Sistema de Análise da Informação do Treinador de Futebol em Competição (SAITFC). Um sistema flexível que inclui dimensões, categorias e subcategorias, as quais remetem para a informação numa tentativa de tornar inclusivo todos os comportamentos relacionadoscom a informação emitida pelo treinador, ajudando a umaelaboração de um perfil comportamental emcompetição. O cálculo de percentagens de acordos, complementada pela estatística de Kappa de Cohen, mostrou níveis fortes de fidelidade para as observações serem utilizadas como ferramenta científica. Com este estudo piloto, os resultados obtidos nesta investigação sugerem que os treinadores emitam cada vez mais informação, não só para os atletas, em forma de instrução e feedback, mas para todos os agentes desportivos envolvidos na competição, nomeadamente equipas de arbitragem, adversária e técnica em forma de conversas. O feedback tende a ser prescritivo, auditivo, dirigido ao atleta, tático e de afetividade neutra. De realçar a expressividade dos feedbacks relacionados com esquemas táticos e de velocidade de reação. O SAITFC enquanto ferramenta de auxílio à sistematização do comportamento do treinador, mostrou ser um método eficaz, contribuindo assim para a formação de treinadores, mas também a nível científico, auxiliando-os no terreno.(AU)


Assuntos
Humanos , Masculino , Feminino , Atletismo/normas , Futebol , Retroalimentação , Mentores , Comunicação , Observação , Psicologia do Esporte , Medicina Esportiva , Esportes/psicologia , Projetos Piloto
10.
Int J Biol Macromol ; 259(Pt 2): 129288, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38211926

RESUMO

Hydroxypropyl methylcellulose (HPMC)-based microparticles and modified starch emulsions (OSA-MS) were loaded with resveratrol and characterized regarding their physicochemical and thermal properties. Both delivery systems were subject to an in vitro gastrointestinal digestion to assess the bioaccessibility of resveratrol. In addition, cell-based studies were conducted after in vitro digestion and cytotoxicity and oxidative stress were assessed. HPMC-based microparticles displayed higher average sizes (d) and lower polydispersity index (PDI) (d = 948 nm, PDI < 0.2) when compared to OSA-MS-based emulsions (d = 217 nm, PDI < 0.3). Both proved to protect resveratrol under digestive conditions, leading to an increase in bioaccessibility. Resveratrol-loaded HPMC-microparticles showed a higher bioaccessibility (56.7 %) than resveratrol-loaded emulsions (19.7 %). Digested samples were tested in differentiated co-cultures of Caco-2 and HT29-MTX, aiming at assessing cytotoxicity and oxidative stress, and a lack of cytotoxicity was observed for all samples. Results displayed an increasing antioxidant activity, with 1.6-fold and 1.4-fold increases over the antioxidant activity of free resveratrol, for HPMC-microparticles and OSA-MS nanoemulsions, respectively. Our results offer insight into physiological relevancy due to assessment post-digestion and highlight the protection that the use of micro-nano delivery systems can confer to resveratrol and their potential to be used as functional food ingredients capable of providing antioxidant benefits upon consumption.


Assuntos
Antioxidantes , Anidridos Succínicos , Humanos , Emulsões/química , Antioxidantes/farmacologia , Resveratrol , Derivados da Hipromelose , Anidridos Succínicos/química , Células CACO-2 , Amido/química , Digestão
11.
Food Funct ; 14(23): 10286-10313, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37947452

RESUMO

Herein, we review the current state-of-the-art on the use of micro- and nano-delivery systems, a possible solution to some of the drawbacks associated with the incorporation of resveratrol in foods. Specifically, we present an overview of a wide range of micro-nanostructures, namely, lipidic and polymeric, used for the delivery of resveratrol. Also, the gastrointestinal fate of resveratrol-loaded micro-nanostructures, as a critical parameter for their use as functional food, is explored in terms of stability, bioaccessibility, and bioavailability. Different micro-nanostructures are of interest for the development of functional foods given that they can provide different advantages and properties to these foods and even be tailor-made to address specific issues (e.g., controlled or targeted release). Therefore, we discuss a wide range of micro-nanostructures, namely, lipidic and polymeric, used to deliver resveratrol and aimed at the development of functional foods. It has been reported that the use of some production methodologies can be of greater interest than others, for example, emulsification, solvent displacement and electrohydrodynamic processing (EHDP) enable a greater increase in bioaccessibility. Additionally, the use of coatings facilitates further improvements in bioaccessibility, which is likely due to the increased gastric stability of the coated micro-nanostructures. Other properties, such as mucoadhesion, can also help improve bioaccessibility due to the increase in gut retention time. Additionally, cytotoxicity (e.g., biocompatibility, antioxidant, and anti-inflammatory) and possible sensorial impact of resveratrol-loaded micro- and nano-systems in foods are highlighted.


Assuntos
Alimento Funcional , Nanoestruturas , Resveratrol , Antioxidantes , Nanoestruturas/química , Lipídeos/química , Polímeros
12.
Food Res Int ; 173(Pt 1): 113282, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803596

RESUMO

Microalgae have characteristics that make them unique and full of potential. Their capacity to generate interesting bioactive molecules can add value to various industrial applications. However, most of these valuable compounds are intracellular, which makes their extraction a major bottleneck. Conventional extraction methodologies have some drawbacks, such as low eco-friendly character, high costs and energy demand, long treatment times, low selectivity and reduced extraction yields, as well as degradation of extracted compounds. The gaps found for these methods demonstrate that emergent approaches, such as ohmic heating, pulsed electric fields, ionic liquids, deep eutectic solvents, or high-pressure processing, show potential to overcome the current drawbacks in the release and extraction of added-value compounds from microalgae. These new processing techniques can potentially extract a variety of compounds, making the process more profitable and applicable to large scales. This review provides an overview of the most important and promising factors to consider in the extraction methodologies applied to microalgae. Additionally, it delivers broad knowledge of the present impact of these methods on biomass and its compounds, raising the possibility of applying them in an integrated manner within a biorefinery concept.


Assuntos
Líquidos Iônicos , Microalgas , Biomassa , Microalgas/metabolismo , Eletricidade
13.
Adv Food Nutr Res ; 106: 317-351, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37722777

RESUMO

This chapter examines how innovative and emerging food processing technologies, such as those that use heat, electricity, electromagnetic waves, and pressure, can modify protein denaturation, aggregation, and intermolecular interactions pathways, which can result in varying immunoreactive responses. It emphasizes the need to understand how these processing methods affect the protein epitopes recognized by antibodies and their respective priming pathways, especially during the sensitization stage that precedes an allergic response. Although traditional processing methods have been investigated, the impact of novel technologies on food protein allergenicity remains largely unknown. The chapter specifically focuses on milk proteins, which have clinical significance and are associated with cow's milk allergy, one of the most common food allergies in young children. Additionally, it examines potential scientific advancements that novel processing methods may bring to this field.


Assuntos
Hipersensibilidade Alimentar , Hipersensibilidade a Leite , Animais , Bovinos , Feminino , Alérgenos , Proteínas do Leite , Manipulação de Alimentos
14.
NPJ Biofilms Microbiomes ; 9(1): 68, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37739955

RESUMO

Biofilms are bacterial communities that result from a cell differentiation process leading to the secretion of an extracellular matrix (ECM) by part of the population. In Bacillus subtilis, the main protein component of the ECM is TasA, which forms a fiber-based scaffold that confers structure to the ECM. The N-terminal half of TasA is strongly conserved among Bacillus species and contains a protein domain, the rigid core (RcTasA), which is critical for the structural and functional properties of the recombinant protein. In this study, we demonstrate that recombinantly purified RcTasA in vitro retains biochemical properties previously observed for the entire protein. Further analysis of the RcTasA amino acid sequence revealed two aggregation-prone stretches and a region of imperfect amino acid repeats, which are known to contribute to functional amyloid assembly. Biochemical characterization of these stretches found in RcTasA revealed their amyloid-like capacity in vitro, contributing to the amyloid nature of RcTasA. Moreover, the study of the imperfect amino acid repeats revealed the critical role of residues D64, K68 and D69 in the structural function of TasA. Experiments with versions of TasA carrying the substitutions D64A and K68AD69A demonstrated a partial loss of function of the protein either in the assembly of the ECM or in the stability of the core and amyloid-like properties. Taken together, our findings allow us to better understand the polymerization process of TasA during biofilm formation and provide knowledge into the sequence determinants that promote the molecular behavior of protein filaments in bacteria.


Assuntos
Proteínas Amiloidogênicas , Bacillus subtilis , Bacillus subtilis/genética , Proteínas Amiloidogênicas/genética , Aminoácidos , Biofilmes , Matriz Extracelular
15.
Nanomaterials (Basel) ; 13(15)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37570554

RESUMO

Nanosized delivery systems have been the subject of research and discussion in the scientific community due to their unique properties and functionality. However, studies reporting the behaviour of nanodelivery systems under dynamic in vitro digestion conditions are still very scarce. To address this gap, this study aims to assess the dynamic in vitro gastric digestion of lactoferrin/curcumin nanoparticles in the realistic gastric model (RGM). For this purpose, the INFOGEST standard semi-dynamic digestion protocol was used. The nanosystems were characterized in terms of hydrodynamic size, size distribution, polydispersity index (PdI), and zeta potential using dynamic light scattering (DLS), before and during the digestion process. Confocal laser scanning microscopy (CLSM) was also used to examine particle aggregation. In addition, the release of curcumin was evaluated spectroscopically and the intrinsic fluorescence of lactoferrin was measured throughout the digestion process. The protein hydrolysis was also determined by UV-VIS-SWNIR spectroscopy to estimate, in real-time, the presence of free NH2 groups during gastric digestion. It was possible to observe that lactoferrin/curcumin nanoparticles were destabilized during the dynamic digestion process. It was also possible to conclude that low sample volumes can pose a major challenge in the application of dynamic in vitro digestion models.

16.
Appl Microbiol Biotechnol ; 107(16): 5063-5077, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37382612

RESUMO

Nannochloropsis oculata is naturally rich in eicosapentaenoic acid (EPA). To turn this microalga into an economically viable source for commercial applications, extraction efficiency must be achieved. Pursuing this goal, emerging technologies such as high hydrostatic pressure (HHP) and moderate electric fields (MEF) were tested, aiming to increase EPA accessibility and subsequent extraction yields. The innovative approach used in this study combined these technologies and associated tailored, less hazardous different solvent mixtures (SM) with distinct polarity indexes. Although the classical Folch SM with chloroform: methanol (PI 4.4) provided the highest yield concerning total lipids (166.4 mglipid/gbiomass), diethyl ether: ethanol (PI 3.6) presented statistically higher values in terms of EPA per biomass, corresponding to 1.3-fold increase. When SM were used in HHP and MEF, neither technology independently improved EPA extraction yields, although the sequential combination of technologies did result in 62% increment in EPA extraction. Overall, the SM and extraction methodologies tested (HHP-200 MPa, 21 °C, 15 min, followed by MEF processing at 40 °C, 15 min) enabled increased EPA extraction yields from wet N. oculata biomass. These findings are of high relevance for the food and pharmaceutical industries, providing viable alternatives to the "classical" extraction methodologies and solvents, with increased yields and lower environmental impact. KEY POINTS: • Et2O: EtOH is a less toxic and more efficient alternative to Folch solvent mixture • HHP or MEF per se was not able to significantly increase EPA extraction yield • Combinations of HHP and MEF technologies increased both lipids and EPA yields.


Assuntos
Microalgas , Estramenópilas , Ácido Eicosapentaenoico , Solventes , Metanol , Etanol , Biomassa
17.
Animals (Basel) ; 13(12)2023 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-37370529

RESUMO

The aim of this study was to evaluate the sprint racing performance of Quarter Horses in Brazil. Estimating genetic parameters, trends and correlations were obtained by single- and two-trait analyses using Bayesian inference (earnings to 2 years of equestrian age, best time and time class at distances of 301 m and 402 m). The data comprised a period of 38 equestrian years (1978 to 2015) with 23,482 sprint race records from 5861 animals. The heritability estimates were of low to moderate magnitude, ranging from 0.10 to 0.37 (single-trait) and from 0.15 to 0.41 (two-traits), and the repeatability was 0.31 to 0.46. The additive, residual and phenotypic correlations between earnings to 2 years of equestrian age and the other traits (best time and time class in distances 301 m and 402 m) were high (-0.95, -0.96, 0.69 and 0.92), low (-0.29, -0.37, 0.26 and 0.27) and moderate (-0.41, -0.47, 0.37 and 0.47), respectively. There is a positive genetic trend for all traits considered. However, evaluation of the last 10 equestrian years (2006 to 2015) showed negative trends (genetic loss) and trends close to zero (genetic stagnation). The design of breeding programs using the earnings trait in conjunction with other racing performance traits can enhance changes in the genetic gains as a whole in speed-racing Quarter Horses. These findings suggest that the traits studied should be included in breeding selection programs for racing Quarter Horses.

18.
Foods ; 12(7)2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37048269

RESUMO

Ecological and safe packaging solutions arise as pivotal points in the development of an integrated system for sustainable meat production. The aim of this study was to assess the effect of a combined chitosan (Ch) + green tea extract (GTE) + essential oil (thyme oil, TO; flaxseed oil, FO; or oregano oil, OO) coating on the safety and quality of vacuum-packaged beef during storage at 4 °C. An optimized bio-based coating formulation was selected (2% Ch + 2% GTE + 0.1% FO) to be applied to three fresh beef cuts (shoulder, Sh; knuckle, Kn; Striploin, St) based on its pH (5.8 ± 0.1), contact angle (22.3 ± 0.4°) and rheological parameters (viscosity = 0.05 Pa.s at shear rate > 20 s-1). Shelf-life analysis showed that the Ch-GTE-FO coating delayed lipid oxidation and reduced total viable counts (TVC) and Enterobacteriaceae growth compared with uncoated beef samples over five days. In addition, Ch-GTE-FO coating decreased total color changes of beef samples (e.g., ∆E* = 9.84 and 3.94, for non-coated and coated Kn samples, respectively) for up to five days. The original textural parameters (hardness, adhesiveness and springiness) of beef cuts were maintained during storage when Ch-GTE-FO coating was applied. Based on the physicochemical and microbial characterization results, the combination of the Ch-GTE-FO coating developed was effective in preserving the quality of fresh beef cuts during refrigerated storage along with vacuum packaging.

19.
Microbiol Spectr ; : e0504522, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36916921

RESUMO

Within bacterial communities, community members engage in interactions employing diverse offensive and defensive tools to reach coexistence. Extracellular-matrix production and sporulation are defensive mechanisms used by Bacillus subtilis cells when they interact with Pseudomonas chlororaphis strains expressing a type VI secretion system (T6SS). Here, we define Tse1 as the main toxin mobilized by the Pseudomonas chlororaphis T6SS that triggers sporulation in Bacillus subtilis. We characterize Tse1 as a peptidoglycan hydrolase that indirectly alters the dynamics and functionality of the Bacillus cell membrane. We also delineate the response of Bacillus cells to Tse1, which through the coordinated actions of the extracellular sigma factor σW and the cytoplasmic histidine kinases KinA and KinB, culminates in activation of the sporulation cascade. We propose that this cellular developmental response permits bacilli to defend against the toxicity of T6SS-mobilized Tse1 effector. IMPORTANCE The study of bacterial interactions is helping to define species-specific strategies used to modulate the competition dynamics underlying the development of community compositions. In this study, we deciphered the role of Pseudomonas T6SS when competing with Bacillus and the mechanism by which a T6SS-toxin modifies Bacillus physiology. We found that Pseudomonas triggers Bacillus sporulation by injecting through T6SS a toxin that we called Tse1. We found that Tse1 is a hydrolase that degrades Bacillus peptidoglycan and indirectly damages Bacillus membrane functionality. In addition, we demonstrated the mechanism by which Bacillus cells increase the sporulation rate upon recognition of the presence of Tse1. Interestingly, asporogenic Bacillus cells are more sensitive to T6SS activity, which led us to propose sporulation as a last resort of bacilli to overcome this family of toxins.

20.
J Am Chem Soc ; 145(12): 6710-6718, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36872864

RESUMO

Previous characterizations of diactinide endohedral metallofullerenes (EMFs) Th2@C80 and U2@C80 have shown that although the two Th3+ ions form a strong covalent bond within the carbon cage, the interaction between the U3+ ions is weaker and described as an "unwilling" bond. To evaluate the feasibility of covalent U-U bonds, which are neglected in classical actinide chemistry, we have first investigated the formation of smaller diuranium EMFs by laser ablation using mass spectrometric detection of dimetallic U2@C2n species with 2n ≥ 50. DFT, CASPT2 calculations, and MD simulations for several fullerenes of different sizes and symmetries showed that thanks to the formation of strong U(5f3)-U(5f3) triple bonds, two U3+ ions can be incarcerated inside the fullerene. The formation of U-U bonds competes with U-cage interactions that tend to separate the U ions, hindering the observation of short U-U distances in the crystalline structures of diuranium endofullerenes as in U2@C80. Smaller cages like C60 exhibit the two interactions, and a strong triple U-U bond with an effective bond order higher than 2 is observed. Although 5f-5f interactions are responsible for the covalent interactions at distances close to 2.5 Å, overlap between 7s6d orbitals is still detected above 4 Å. In general, metal ions within fullerenes should be regarded as templates in cage formation, not as statistically confined units that have little chance of being observed.

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