Validation and optimization of β-galactosidasev production by Aspergillus lacticoffeatus

Dissertação de mestrado em Bioengenhariaβ-galactosidases (EC 3.2.1.23), also known as lactases, are a family of enzymes that are able to catalyze two different reactions, namely the hydrolysis of lactose and transgalactosylation. The hydrolytic activity is commonly applied in the food industries for reducing the lactose content on dairy products, but it is also important to prevent lactose crystallization problems and to increase the sweetening capacity. Transgalactosylation reactions had been used to synthesize lactose derivatives, such as galactooligosaccharides (GOS), lactulose and lactosucrose. These compounds are classified as prebiotics, which are functional food ingredients, are not digested on the gastrointestinal (GI) tract and are able to stimulate the growth or activity of health-promoting bacteria. The sources of β-galactosidases are extensively distributed in nature, namely in microorganisms, plants and animal organs. Aspergillus lacticoffeatus was chosen for this work as a potential β-galactosidase producer based on preliminary chromogenic tests performed in agar plates. Herein, additional studies carried out under submerged fermentation conditions confirmed the presence of β-galactosidase in the fermentation broth, as well as in the cell extract obtained after cell disruption by ultrasounds. Therefore, this work represents the first time that A. lacticoffeatus is described as a β-galactosidase producer. The enzyme production was evaluated in different fermentation media: synthetic medium composed by lactose (20 g/L), yeast extract (4 g/L), peptone (4 g/L) and salts; and alternative fermentation media with some industrial by-products such as cheese whey and corn steep liquor (CSL). The highest values of extracellular enzymatic activity (444 U/L) were obtained using the synthetic medium. The extracellular enzyme presented a molecular weight between 70–150 kDa and optimal pH and temperature in the range 3.5–4.5 and 50–55 ºC, respectively. The effect of some metal ions (Na+, K+, Li+, Ba2+, Fe2+, Mg2+, Zn2+, Mn2+, Co2+ and Cu2+), detergents (Triton, SDS and Tween), additives (EDTA, PMSF and ascorbic acid) and sugars (glucose, fructose and galactose) on the enzymatic activity was also evaluated. Finally, the potential application of the enzyme for the synthesis of lactose-based prebiotics was studied and it was demonstrated that the β-galactosidase from A. lacticoffeatus is able to catalyze the transfer reactions involved in the formation of lactulose and GOS.As β-galactosidases (EC 3.2.1.23), também conhecidas como lactases, são uma família de enzimas capazes de catalisar dois tipos diferentes de reações, nomeadamente a hidrólise da lactose e a transgalactosilação. A atividade hidrolítica é frequentemente aplicada na indústria alimentar na redução do conteúdo de lactose em produtos lácteos, mas é também importante na prevenção da cristalização da lactose e no aumento da capacidade adoçante. As reações de transgalactosilação têm sido usadas na síntese de derivados de lactose, tais como galacto-oligossacáridos (GOS), lactulose e lactosucrose. Estes compostos são classificados como prebióticos, ou seja, ingredientes de alimentos funcionais que não são digeridos no trato gastrointestinal e são capazes de estimular o crescimento ou atividade de bactérias benéficas para a saúde. As fontes de β-galactosidases estão amplamente distribuídas pela natureza, nomeadamente em microrganismos, plantas e órgãos animais. Aspergillus lacticoffeatus foi escolhido para este trabalho como potencial produtor de enzima tendo em conta os resultados preliminares de testes cromogénicos realizados em placas de agar. Neste trabalho, estudos adicionais conduzidos sob fermentações submersas confirmaram a presença de β-galactosidase no caldo da fermentação, assim como no extrato celular obtido após rutura celular por ultrassons. Desta forma, A. lacticoffeatus é aqui pela primeira vez descrito como um produtor de β-galactosidase. A produção da enzima foi avaliada em diferentes meios de fermentação: meio sintético composto por lactose (20 g/L), extrato de levedura (4 g/L), peptona (4 g/L) e sais; e meios alternativos constituídos por resíduos industriais como o soro de queijo e corn steep liquor (CSL). Contudo, os valores mais elevados de atividade enzimática extracelular (444 U/L) foram obtidos usando o meio sintético. A enzima produzida extracelularmente apresentou um peso molecular entre 70 e 150 kDa e o pH e temperaturas ótimos num intervalo entre 3.5–4.5 e 50–55 ºC, respetivamente. O efeito de iões metálicos (Na+, K+, Li+, Ba2+, Fe2+, Mg2+, Zn2+, Mn2+, Co2+ e Cu2+), detergentes (Triton, SDS e Tween), aditivos (EDTA, PMSF e ácido ascórbico) e açúcares (glucose, frutose e galactose) na atividade enzimática foi também avaliado neste trabalho. Finalmente, a potencial aplicação da enzima na produção de prebióticos derivados de lactose foi estudada, tendo-se demonstrado que esta β-galactosidase de A. lacticoffeatus é capaz de catalisar as reações de transferência envolvidas na formação de lactulose e GOS

Development of a cost-effective media for biosurfactants production by Pseudomonas aeruginosa

In the last years, the textile industry has shown a growing interest in biosurfactants due to their biocompatibility , biodegradability , and versatility at various pH and temperature ranges . These compounds have found applications as softeners, wetting agents, lubricants, foam stabilizers, and even in the scouring of wool. This study aims to develop an economically efficient medium for biosurfactant production by Pseudomonas aeruginosa #112. Firstly , waste cooking oils after treatment (WCOT), a residue rich in lipids, was evaluated as an inducer of biosurfactants production . Different concentrations of these substrates (1, 2.5, 5, and 10 % w/v) were tested, and glucose was used as a carbon source. In the experiments with 1 % of WCOT it was observed a significant (p 0.05) reduction in the surface tension from 48.4 mN/m to 34.8 mN/m, suggesting the biosurfactant production . Furthermore , rice husk (RH) and vine pruning (VP) residues were identified as alternative carbon sources for biosurfactants production, when combined with WCOT . Both residues are rich in cellulose, which can be broken down into free glucose. An enzymatic pre- treatment that combines xylanase and cellulase was used to hydrolyze residues and release free glucose . The obtained results demonstrate that the combination of 1 % OUAT with hydrolyzed RH or VP resulted in a substantial (53 %) reduction in surface tension. At the end of the fermentation, 1.65 g/L and 0.26 g/L of biosurfactant were recovered for the experiments with hydrolyzed PV and RH, respectively. Additionally, the critical micelle dilution results demonstrate that the two tested media allow biosurfactant production and effective reduction of the surface tension of distilled water , even at low concentrations . This is the first report of biosurfactant production using a mixture of these three agro-industrial residues , which can be very useful for the sustainable production of these promising molecules.The authors acknowledge the financial support from integrated project be@t – Textile Bioeconomy (TCC12-i01, Sustainable Bioeconomy No. 02/C12-i01/2022), promoted by the Recovery and Resilience Plan (RRP), Next Generation EU, for the period 2021 – 2026. The authors also acknowledge the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit.info:eu-repo/semantics/publishedVersio

Agro-industrial wastes as alternative substrates for the production of prebiotic with Zymomonas mobilis

Fructooligosaccharides (FOS) are promising prebiotics in the relevant and increasing market of functional food. However, to achieve a more sustainable process, the industrial production of FOS should use cheap substrates. Zymomonas mobilis (ZM) has great potential for the production of FOS due to the presence of native enzymes (levansucrase) capable of metabolizing sucrose. In addition, ZM can use different carbon sources, such as molasses and sugarcane juice, which make the FOS production process cost-effective. In this study, sugarcane molasses (a potential replacement of sucrose) and corn step liquor (CSL) (a potential replacement of yeast extract (YE)), were used as nutrients for FOS production using ZM in an in vivo bioprocess approach. FOS production process from sucrose was first optimized and 52 g/L of FOS with a yield of 0.16 g/g was obtained. Afterwards, molasses and CSL were used as alternative nutrients. After studying different combinations of CSL and YE, the highest amount of FOS (54 g/L, with a yield of 0.18 g/g) was obtained with 12 g/L of CSL and 8 g/L of YE. In addition, 45 g/L of FOS were produced from molasses containing 200 g/L of sucrose, with a yield of 0.3 g/g. With this approach, it was possible to reduce around 5.5-times the cost associated with the FOS production medium. Moreover, this study proposed a sustainable process for the valorization of agro-industrial wastes contributing to the future Circular (Bio)Economy and the EU Green Deal.Cláudia Amorim, João Rainha, Beatriz B. Cardoso and Daniela Gomes acknowledge their grants (2020.0029.CEECIND, SFRH/BD/138325/2018, SFRH/BD/132324/2017 and SFRH/BD/04433/2020, respectively) from Portuguese Foundation for Science and Technology (FCT). The study received financial support from Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and by LABBELS – Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, LA/P/0029/2020.info:eu-repo/semantics/publishedVersio

Zymomonas mobilis an emerging microbial cell factory to produce prebiotics

info:eu-repo/semantics/publishedVersio

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For schoolaged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesit

Educomunicação e suas áreas de intervenção: Novos paradigmas para o diálogo intercultural

oai:omp.abpeducom.org.br:publicationFormat/1O material aqui divulgado representa, em essência, a contribuição do VII Encontro Brasileiro de Educomunicação ao V Global MIL Week, da UNESCO, ocorrido na ECA/USP, entre 3 e 5 de novembro de 2016. Estamos diante de um conjunto de 104 papers executivos, com uma média de entre 7 e 10 páginas, cada um. Com este rico e abundante material, chegamos ao sétimo e-book publicado pela ABPEducom, em seus seis primeiros anos de existência. A especificidade desta obra é a de trazer as “Áreas de Intervenção” do campo da Educomunicação, colocando-as a serviço de uma meta essencial ao agir educomunicativo: o diálogo intercultural, trabalhado na linha do tema geral do evento internacional: Media and Information Literacy: New Paradigms for Intercultural Dialogue

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost