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- Acidifying and aromatic properties of enterococcus strains in ovine and bovine milksPublication . Pimentel, L. L.; Soares, J. C.; Pintado, M. M. E.; Pintado, A. I. E.; Gomes, A. M. P.; Ferreira, A. C.; Malcata, F. X.Enterococci are lactic acid bacteria present in a wide variety of dairy and other food products. Although their presence in the former has been considered an indicator of poor hygienic conditions, nowadays a number of biotechnological and probiotic useful characteristics are already known. A few compounds resulting from the bacterium metabolism contribute to the aroma of cheese. Knowledge of those components, as well as of the acidifying capacity is very important to the dairy industry, including application toward selection of strains as better starters. The aim of this research effort was to study the role of some enterococci in ovine and bovine milks, in terms of acidifying properties and aroma potential. A total of seven strains, previously isolated from traditional Portuguese cheeses, were assayed for: Enterococcus faecium 28A, E. durans 13 and E. faecalis 6 (from Serra da Estrela cheese); and E. faecium 42, E. durans 15, E. faecalis 3 and E. casseliflavus 40 (from Terrincho cheese). Sterilized ovine and bovine milks were inoculated with 2% (v/v) inoculum and incubated at 37 °C. Microbiological viable counts on M17 agar, pH and titrable acidity were determined in duplicate at 0, 1, 4 and 7 d of incubation. Free fatty acids, recognized as strong odorants in Serra da Estrela and other traditional Portuguese cheeses, were quantified in each sample using SPME – GC/MS. All strains showed similar growth patterns, either in bovine or ovine milks, and reached levels of 108 –109 cfu/ml by 1 d of incubation (except E. durans 13, which exhibited a better growth in bovine than ovine milk). An important decrease in pH was observed in both types of milk by 1 d, for all strains. The highest reduction was observed for E. casseliflavus 40 and E. durans 15 in bovine milk, and for E. faecium 42 and E. durans 13 in ovine milk. Enterococcus faecalis 6 revealed the poorest acidification power.
- Aerobic granular sludge: treatment of wastewaters containing toxic compoundsPublication . Amorim, Catarina L.; Moreira, Irina S.; Duque, Anouk F.; Loosdrecht, Mark C. M. van; Castro, P. M. L.Aerobic Granular Sludge (AGS) has been successfully applied for carbon, nitrogen and phosphorous removal from wastewaters, in a single tank, reducing the space and energy requirements. This is especially beneficial for, often space restricted, industrial facilities. Moreover, AGS holds a promise for the toxic pollutants removal, due to its layered and compact structure and the bacteria embedding in a protective extracellular polymeric matrix. These outstanding features contribute to AGS tolerance to toxicity and stability. Strategies available to deal with toxic compounds, namely granulation with effluents containing toxics and bioaugmentation, are addressed here. Different applications for the toxics/micropollutants removal through biosorption and/or biodegradation are presented, illustrating the technology versatility. The anthropogenic substances effects on system performance and bacterial populations established within AGS are also addressed. Combination of contaminants removal to allow water discharge, and simultaneous valuable products recovery are presented as final remark.
- AgroForest biomass and circular bioeconomy: case studiesPublication . Leitão, Alexandra; Rebelo, Francisco; Pintado, Manuela; Ribeiro, Tânia BragançaThe agroforest sector plays a leading role as a biomass supplier to obtain bio-based products that allowed an acceleration in the circular bioeconomy transition. This chapter applied a mixed-methods review to identify new attractive bio-based products and to evaluate its market potential in Portugal. Forest biomass was identified as an excellent raw material for (1) low-carbon building materials, (2) biotextiles, and (3) bioplastics. The potential of agro-food waste to obtain new bio-based materials was also emphasised. The new bioproducts identified have high potential and attractive markets. It was estimated that a 5% market share of these bioproducts in the global construction, textiles, and plastics markets in 2030 corresponds to an aggregate increase in revenues of 260-579 million € per year in Portugal. The environmental sustainability implications arising from the diffusion of these new biomaterials are also highlighted, focusing on the decarbonisation of the economy.
- AlicycliphilusPublication . Nunes, Olga C.; Manaia, Célia M.; Vaz-Moreira, IvoneAlicycliphilus (A.li.cy.cli'phi.lus. Gr. neut. n. aleiphar annointing oil; Gr. masc. n. kyklos circle or ring; Gr. masc. n. philos friend; N.L. masc. n. Alicyciphilus alicyclic compound liking, referring to the substrates used for the isolation of this organism). Proteobacteria / Betaproteobacteria / Burkholderiales / Comamonadaceae / Alicycliphilus. Short rods, 1–2 μm long and 0.6 μm wide. Motile. Gram‐negative. Nonsporulating. Facultative anaerobe. Nitrate is reduced to N2. Mesophilic, with optimal growth at 28–30°C and pH 7.2–7.4 under aerobic or anoxic conditions. Chemoorganotroph, with strictly respiratory metabolism. Degrade aromatic and alicyclic compounds. Catalase‐ and cytochrome c oxidase‐positive. The respiratory quinone is ubiquinone 8, and major fatty acids are C16:1 ω7c, C16:0, and C18:1 ω7c. Major polar lipids are hosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol. The type strain of the type species was isolated from a wastewater treatment plant, cultivated with cyclohexanol as sole carbon source and nitrate as electron acceptor. DNA G + C content (mol%): 66 (HPLC) or 67.9 (genome analysis, GenBank). Type species: Alicycliphilus denitrificans Mechichi et al. 2003VP.
- Alimentação e nutrição na pessoa idosa: obesidade, diabetes mellitus, doenças cardiovasculares e hipertensão arterialPublication . Popa, Cezara; Mateus, Maria Palma; Correia, Maria Marta; Braz, Nídia
- Alimentação e nutrição na pessoa idosa: risco nutricional, necessidades nutricionais e estratégias alimentaresPublication . Popa, Cezara; Mateus, Maria; Correia, Maria Marta; Braz, Nidia
- Analytical approaches for proteomics and lipidomics of arsenic in algaePublication . Freitas, Ana Cristina; Gomes, Ana MariaArsenic (As) is an element with a complex chemistry found in relatively high concentrations in the marine environment. A diverse group of As compounds or As species exist in the marine environment and these are of importance to human health given their potential cytotoxicity. It has been pointed out that marine algae are the origin of such As compounds, since they accumulate arsenate from seawater and metabolize it into several organoarsenic species of both lipophilic and hydrophilic nature. In this chapter, it is intended to discuss lipidomics approaches for identification of the > 70 existing lipophilic arsenic species (arsenolipids) in algae which include arsenic incorporated into phospholipids, hydrocarbons, long-chain alcohols, and polyunsaturated fatty acids. In turn, proteomic analysis will also be presented and discussed in its role, for example, to investigate whether cells show a specific response or survival strategy when under arsenic-induced stress. Research on proteome involvement in stress and tolerance to arsenic offers new tools to understand the associated physiological and biochemical mechanisms connected with different algae responses. Protein biomarkers are also of interest to enable indication of quantitative changes in some physiological parameters as the result of stress or toxicity.
- Angiotensin-converting enzyme-inhibitory activity of extracts of hydrolysed k-casein glycomacropeptide: stability under simulated gastrointestinal digestionPublication . Tavares, Tânia; Amorim, Manuela; Pintado, Manuela; Récio, Isidra; Malcata, F. XavierDietary proteins usually possess a wide range of nutritional, functional and biological properties; many of such biological properties have been attributed to physiologically active peptides, which are encrypted within the protein sequence. k‐Casein glycomacropeptide (CMP) – one of the main components of whey, is released in the first step of (enzymatic) cheese making – and has been claimed to act as mediator in important biological pathways. Peptides released from CMP via enzymatic or microbial activity have indeed been proven to posses inhibitory activity against the angiotensin‐converting enzyme (ACE). However, they will not act properly in the human body unless they can resist gastrointestinal digestion, as well as be absorbed and reach the cardiovascular system in active form. On the other hand, several studies have already demonstrated the important role of gastrointestinal digestion upon ACE‐inhibitory peptide formation. Therefore, the aim of this study was to evaluate the ACE‐inhibitory activity of peptide extracts obtained via hydrolysis of CMP, using an extract of Cynara cardunculus as enzymatic vector. Moreover, such peptides were subjected to simulated gastrointestinal digestion, in order to assess their stability and the evolution of their ACE‐inhibitory activity. A 40 g/L solution of CMP, hydrolysed with 8.5 %(w/w) commercial crude extract of C. cardunculus, exhibitedACE‐inhibitory activity corresponding to IC50 values of 296.0 mg/mL (total fraction), 63.0 mg/mL (3000 Da fraction). The identification of peptides proceeded by LC‐MS, and permitted identification of the following peptides: MAIPPKKNDQD (k‐CN f106‐115), as potentially responsible for antihypertensive activity; and TVQVTSTAV (k‐CN f161‐169) and MAIPPKKNDQD (k‐CN f106‐115), as potentially responsible for antithrombotic activity, because both encompass sequences analogous to the bioactive fragment f400‐411 of fibrinogen g‐chain. A new peptide, KTEIPIN (k‐CN f116‐123), was also identified to relatively high concentrations, with a promising antihypertensive activity. Studies concerning the in vitro simulation of gastrointestinal digestion were conducted; the gastrointestinal stability of the total extract and of the 3000 Da peptide fraction, as well as of the plain CMP (used as control), following incorporation in water and fruit juice, was tested in said gastrointestinal model, but none of said fractions was significantly affected.
- Antibiotic resistance in the environment: expert perspectivesPublication . Manaia, Célia M.; Graham, David; Topp, Edward; Martinez, José Luis; Collignon, Peter; Gaze, William H.Antibiotic resistance is considered by different international organisations (e.g. World Health Organization, WHO; Food and Agriculture Organization of the United Nations, FAO-UN; Organisation for Economic Co-operation and Development, OECD) as not only a major threat to human life and wellbeing but also having tremendous economic impacts. Recent estimates indicate that globally at least 700,000 deaths per year are due to drug-resistant infections, with the largest and most important proportion of these attributable to antibiotic-resistant bacterial infections – and which are most often identified in hospitals. However, there are reasons to believe that antibiotic-resistant bacteria are common in the community, where they are acquired from other people, animals, foods, water and/or other environmental sources. Over recent decades, the importance of the environment in the propagation and dissemination of antibiotic-resistant bacteria has been better evidenced, with human and animal sewage representing the most important emission nodes in a complex network of transmission routes. While the relevance of environmental sources and paths of transmission are nowadays considered pivotal in any One Health discussion about antibiotic resistance, some key topics are still under debate in the scientific community. In this chapter, experts recognised in the field were invited to give their perspective on some commonly debated topics related to the risks and control of antibiotic resistance. Specifically, five invited experts gave their perspective on the relevance and control of the environmental dimensions of antibiotic resistance, based on six distinct thematic axes – transmission, critical control points, antibiotic-selective effects, interventions needed, authority’s awareness and engagement and priorities for action.
- Antibiotic resistance in waste water and surface water and human health implicationsPublication . Manaia, C. M.; Vaz-Moreira, Ivone; Nunes, Olga C.The utilization of antibiotics to control infectious diseases is one of the biggest advances in human and veterinary health care. However, the generalized use of antibiotics has been accompanied by a worrisome increase in the prevalence of antibiotic-resistant bacteria. This evidence motivated numerous studies on the diversity and distribution of antibiotic-resistant bacteria and resistance genetic determinants not only in clinic but also in different environmental compartments. Given the particular importance that the anthropic water cycle (waste water/surface water/drinking water) may have in the development and dissemination of antibioticresistant organisms, this chapter aims at summarizing the recent advances in this area. Sections 1 and 2 are an Introduction to antibiotic resistance, summarizing some mechanisms and modes of resistance acquisition. In Sect. 3, the contribution of the environmental pollution and other anthropic pressures for antibiotic resistance evolution is discussed. The use of different methodologies and the limitations to achieve general conclusions on the characterization and quantification of antibiotic resistance in aquatic environments are examined in Sects. 4 and 7. Sections 5–7 summarize recent evidences on the widespread distribution of antibiotic resistance in different compartments of the anthropic water cycle. The scarcity of studies giving evidences on the direct effect of anthropic pressures on antibiotic resistance acquisition and maintenance in treated waste/drinking waters is highlighted. The contribution of bacterial community rearrangement, imposed by water treatment processes, on the increase of antibiotic resistance is discussed.