Biovalorization of lignocellulosic materials for xylitol production by the yeast komagataella pastoris

The main goal of this study was to screen different lignocellulosic materials for their ability to support the cell growth of the yeast Komagataella pastoris and the production of xylitol. Several lignocellulosic materials, namely banana peels, brewer’s spent grains (BSGs), corncobs, grape pomace, grape stalks, and sawdust, were subjected to dilute acid hydrolysis to obtain sugar rich solutions that were tested as feedstocks for the cultivation of K. pastoris. Although the culture was able to grow in all the tested hydrolysates, a higher biomass concentration was obtained for banana peels (15.18 ± 0.33 g/L) and grape stalks (14.58 ± 0.19 g/L), while the highest xylitol production (1.51 ± 0.07 g/L) was reached for the BSG hydrolysate with a xylitol yield of 0.66 ± 0.39 g/g. Cell growth and xylitol production from BSG were improved by detoxifying the hydrolysate using activated charcoal, resulting in a fourfold increase of the biomass production, while xylitol production was improved to 3.97 ± 0.10 g/L. Moreover, concomitant with arabinose consumption, arabitol synthesis was noticed, reaching a maximum concentration of 0.82 ± 0.05 g/L with a yield on arabinose of 0.60 ± 0.11 g/g. These results demonstrate the feasibility of using lignocellulosic waste, especially BSG, as feedstock for the cultivation of K. pastoris and the coproduction of xylitol and arabitol. Additionally, it demonstrates the use of K. pastoris as a suitable microorganism to integrate a zero-waste biorefinery, transforming lignocellulosic waste into two high-value specialty chemicals with high market demand.publishersversionpublishe

As descendências de filho único e o childlessness na coorte de mulheres nascidas entre 1964 e 1968

A sociedade portuguesa atualmente experimenta um contexto de muito baixa fecundidade. Num cenário em que se verifica um contínuo adiamento da entrada na parentalidade torna-se de fundamental importância verificar em que medida o adiamento da entrada na maternidade pode influenciar a fecundidade final dos indivíduos. Neste trabalho pretende-se explorar a fecundidade final de uma coorte de mulheres nascidas entre 1964 e 1968 que estavam a encerrar o seu percurso reprodutivo em 2013

Depois dos 35 anos, quais as intenções de fecundidade dos sul-europeus?

Sendo a baixa fecundidade comum na Europa do Sul, e considerando que nas últimas décadas tanto homens como mulheres têm vindo a adiar a entrada na parentalidade, interessa estudar os determinantes das intenções de fecundidade. Em particular, dos sul-europeus com mais de 35 anos, idade a partir da qual se considera que aqueles que não têm filhos, ou que têm apenas um, se encontram a adiar os seus projetos de fecundidade. Os resultados mostram que perceções negativas em relação à situação do país são inibidoras no processo da tomada de decisão de ter filhos, especialmente o segundo filho. Este trabalho remete para a importância de considerar valores e expectativas dos indivíduos em relação à sua vida e à situação do país como preditores do comportamento reprodutivo.Because low fertility is common in Southern European countries and considering that in recent decades both men and women have been postponing their fertility projects, it is of our interest to study the determinants of reproductive decision-making. Particularly, of Southern Europeans older than 35, age from which it is considered that those who have no children, or that have only one child, have postponed their fertility projects. The findings show that negative perceptions about the situation of the country inhibit the process of having a child, specially the second one. This paper reports to the importance of considering values and perceptions of individuals about their lives and the situation of the country as predictors of fertility behaviour.Depuis quelques décennies, alors que le taux de fécondité est bas dans les pays du sud de l’Europe, les femmes comme les hommes tendent à repousser l’âge de la parentalité. Cet article étudie les facteurs déterminants des intentions de fécondité, en particulier des sud-européens de plus de 35 ans, l’âge à partir duquel on considère que ceux qui n’ont pas d’enfants ou qui n’en ont qu’un seul repoussent à plus tard leurs projets de fécondité. Les résultats montrent que les perceptions négatives sur la situation du pays sont inhibitrices dans la prise de décision d’avoir des enfants, en particulier s’il s’agit du deuxième enfant. Ce travail souligne combien les valeurs et les attentes des individus concernant leur vie et la situation du pays sont révélatrices de leur comportement reproductif.Siendo común la baja fecundidad en Europa del Sur y considerando que en las últimas décadas tanto hombres como mujeres han venido atrasando la entrada en la parentalidad, interesa estudiar los determinantes de las intenciones de fecundidad. En particular, de los sur-europeos con más de 35 años, edad a partir de la cual se considera que aquellos que no tienen hijos, o que tienen apenas uno, se encuentran atrasando sus proyectos de fecundidad. Los resultados muestran que percepciones negativas en relación a la situación del país son inhibidoras en el proceso de la toma de decisión de tener hijos, especialmente el segundo hijo. Este trabajo confirma la importancia de considerar valores y expectativas de los individuos en relación a su vida y a la situación del país como predictores del comportamiento reproductivo

Depois dos 35 anos, quais as intenções de fecundidade dos Sul-Europeus?

Because low fertility is common in Southern European countries and considering that in recent decades both men and women have been postponing their fertility projects, it is of our interest to study the determinants of reproductive decision-making. Particularly, of Southern Europeans older than 35, age from which it is considered that those who have no children, or that have only one child, have postponed their fertility projects. The findings show that negative perceptions about the situation of the country inhibit the process of having a child, specially the second one. This paper reports to the importance of considering values and perceptions of individuals about their lives and the situation of the country as predictors of fertility behaviour

Childlessness in later ages in Portugal and in Southern European Countries

It is argued that parenthood is no longer a basic condition for achieving self- realization and that the choice of a life without children (childfree) has become increasingly common and free of stereotypes (Basten, 2009), transforming the desired and ideal family size in one of the most important determinants of future fertility. However, it is also necessary to recognize the importance of education level and employment status in the choice of a childfree life (Koropeckyj-cox & Pendel, 2007; Mendes et al., 2015). Moreover, the recent economic and social situation in some European countries effectively altered individual’s fertility behaviour. Particularly, in Southern European countries, which were more battered by the economic crisis, there was a consolidation of a fertility postponement pattern with a strong concentration of births around age 30 (Sobotka, 2013; Mendes, 2012; Mendes et al., 2015). For the past decades, the number of individuals who end their reproductive lives without children has been increasing (Tanturri & Mencarini, 2008; Cunha, 2012; Mendes, 2012), which is, in large part, the result of the postponement of parenthood. Despite the apparent postponement of fertility projects, we know little about reproductive intentions of Southern Europeans after age 30 - age at which the decision to have a child may begin to be compromised by biological limits. Hence, we are particularly interested in analysing those individuals who have reached their 30’s without children and we try to define the profile of those who are more likely to remain childless

Childlessness in later ages in Portugal and in Southern European Countries

It is argued that parenthood is no longer a basic condition for achieving self- realization and that the choice of a life without children (childfree) has become increasingly common and free of stereotypes (Basten, 2009), transforming the desired and ideal family size in one of the most important determinants of future fertility. However, it is also necessary to recognize the importance of education level and employment status in the choice of a childfree life (Koropeckyj-cox & Pendel, 2007; Mendes et al., 2015). Moreover, the recent economic and social situation in some European countries effectively altered individual’s fertility behaviour. Particularly, in Southern European countries, which were more battered by the economic crisis, there was a consolidation of a fertility postponement pattern with a strong concentration of births around age 30 (Sobotka, 2013; Mendes, 2012; Mendes et al., 2015). For the past decades, the number of individuals who end their reproductive lives without children has been increasing (Tanturri & Mencarini, 2008; Cunha, 2012; Mendes, 2012), which is, in large part, the result of the postponement of parenthood. Despite the apparent postponement of fertility projects, we know little about reproductive intentions of Southern Europeans after age 30 - age at which the decision to have a child may begin to be compromised by biological limits. Hence, we are particularly interested in analysing those individuals who have reached their 30’s without children and we try to define the profile of those who are more likely to remain childless

A influência dos laços familiares na qualidade de vida dos idosos : um estudo numa instituição de acolhimento

Os dados demográficos demonstram uma tendência acentuada do envelhecimento populacional, com consequências nos apoios e nas estruturas das famílias, o que originará num futuro próximo, novas necessidades de saúde para as quais os idosos, famílias e comunidade, não estarão preparados. A família é a instituição na qual a pessoa insere-se e desenvolve-se, ao longo das etapas do ciclo de vida. Portanto é uma estrutura de apoio responsável por garantir a realização e a satisfação das necessidades, sentidas pela pessoa aquando do envelhecimento. Atualmente, em resultado das alterações, a família não consegue responder às necessidades dos seus membros e consequentemente recorre ao apoio formal, como a utilização de instituições de acolhimento. O envelhecimento corresponde a uma fase do ciclo de vida, que acarreta transformações nas várias dimensões da vida dos idosos e conforme as previsões estatísticas apontam ocorrerá um contínuo aumento. Desta forma, a família, a comunidade e os profissionais de saúde devem promover um envelhecimento com qualidade de vida. A enfermagem deve construir intervenções no sentido da promoção de um envelhecimento com qualidade de vida, capacitando os idosos, famílias e comunidade. O presente estudo teve como objetivo aprofundar o conhecimento sobre a influência dos laços familiares na qualidade de vida dos idosos de uma instituição de acolhimento. Contribuindo para uma melhor prestação de cuidados em enfermagem comunitária, na área do envelhecimento com qualidade de vida. Realizei um estudo quantitativo, descritivo – correlacional e transversal, a questão de investigação que norteou o estudo VI foi: qual a influência dos laços familiares na qualidade de vida dos idosos de uma instituição de acolhimento. O estudo foi realizado numa instituição de acolhimento de idosos, frequentada maioritariamente por pessoas com profissões ligadas à pesca. Das unidades de centro dia e lar da instituição selecionada, obtive uma população de 39 idosos. Para estudar a influência dos laços familiares contactei os familiares dos idosos, conseguindo avaliar a perceção da funcionalidade familiar de 11 familiares de 11 idosos. Para colheita de dados recorri às escalas FAD (Family Assessment Device) e WHOQOL-Bref (World Health Organization Quality of Life-Bref). Ambas as escalas estão traduzidas e validadas para a população portuguesa pelos grupos de trabalho das respetivas escalas. A FAD avalia a funcionalidade familiar segundo a perceção dos membros da família e tem por base o Modelo de McMaster do Funcionamento Familiar (MMFF). A escala WHOQOL-Bref foi desenvolvida pela Organização Mundial da Saúde (OMS) e avalia quatro domínios da qualidade de vida: físico, psicológico, relações sociais e ambiente. Os resultados obtidos evidenciaram que os idosos que percecionavam a funcionalidade familiar da sua família como saudável, ou seja, família com boa funcionalidade familiar, apresentavam melhor nível de qualidade de vida. Da análise da perceção dos idosos e da perceção dos elementos da família constatei que existiam divergências, os idosos identificavam mais dimensões não saudáveis na família, ao contrário dos elementos da família, o que reflete que os diferentes elementos da família percecionavam as mudanças decorridas de forma distinta

Chitin-Glucan Complex Hydrogels: Optimization of Gel Formation and Demonstration of Drug Loading and Release Ability

Chitin-glucan complex (CGC) hydrogels were fabricated through a freeze–thaw procedure for biopolymer dissolution in NaOH 5 mol/L, followed by a dialysis step to promote gelation. Compared to a previously reported methodology that included four freeze–thaw cycles, reducing the number of cycles to one had no significant impact on the hydrogels’ formation, as well as reducing the total freezing time from 48 to 18 h. The optimized CGC hydrogels exhibited a high and nearly spontaneous swelling ratio (2528 +- 68%) and a water retention capacity of 55 +- 3%, after 2 h incubation in water, at 37 ºC. Upon loading with caffeine as a model drug, an enhancement of the mechanical and rheological properties of the hydrogels was achieved. In particular, the compressive modulus was improved from 23.0 +-0.89 to 120.0 +- 61.64 kPa and the storage modulus increased from 149.9 +- 9.8 to 315.0 +- 76.7 kPa. Although the release profile of caffeine was similar in PBS and NaCl 0.9% solutions, the release rate was influenced by the solutions’ pH and ionic strength, being faster in the NaCl solution. These results highlight the potential of CGC based hydrogels as promising structures to be used as drug delivery devices in biomedical applicationsinfo:eu-repo/semantics/publishedVersio

Biosorption of heavy metals by the bacterial exopolysaccharide fucopol

FCT/MCTES (UIDB/04378/2020). Patricia Concordio-Reis acknowledges FCT/MCTES for PhD grant SFRH/BD/131947/2017.Despite the efforts for minimizing the usage of heavy metals, anthropogenic activities still generate high amounts of wastewater containing these contaminants that cause significant health and environmental problems. Given the drawbacks of the conventional physical and chemical methods currently used, natural biosorbents (microbial cells or their products) arise as promising environmentally friendly alternatives. In this study, the binding efficiency of the polysaccharide secreted by Enterobacter A47, FucoPol, towards lead (Pb2+), cobalt (Co2+), copper (Cu2+) and zinc (Zn2+) cations was demonstrated. FucoPol revealed a higher performance for the biosorption of Pb2+, with a maximum overall metal removal of 93.9 ± 5.3% and a specific metal uptake of 41.1 ± 2.3 mg/gEPS, from a Pb2+ solution with an initial concentration of 10 mg/L, by a 5 g/L FucoPol solution. The overall metal removal decreased considerably (≤31.3 ± 1.6%) for higher Pb2+ concentrations (48 and 100 mg/L) probably due to the saturation of FucoPol's binding sites. Pb2+ removal was also less efficient (66.0 ± 8.2%) when a higher FucoPol concentration (10 g/L) was tested. Pb2+ removal efficiency of FucoPol was maximized at pH 4.3, however, it was affected by lower pH values (2.5-3.3). Moreover, the FucoPol's sorption performance was unaffected (overall metal removal: 91.6-93.9%) in the temperature range of 5-40 °C. These findings demonstrate FucoPol's great potential for utilization as a biodegradable and safe biosorbent for treating waters and wastewaters contaminated with Pb2+.publishersversionpublishe