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Background:Hope has long been considered essential to humans in several disciplines, nursing included. At the end-of-life, hope is a complex and dynamic emotion, and there have been different interpretations and conceptions of hope.Aim:To develop hope in palliative care as an evidenced-based nursing concept: analyse its attributes, antecedents and consequences.Method:This study follows Walker and Avant's concept analysis: (a) select a concept; (b) determine the aims or purposes of analysis; (c) identify as many uses of the concept as possible; (d) determine the defining attributes; (e) identify a model case; (f) identify borderline and contrary cases; (g) identify antecedents and consequences; and finally (h) define the empirical referents.Findings:Antecedents included symptom control, existential suffering, interpersonal relationships and the establishment of realistic goals. The synthetic attributes were a positive outcome expectancy and a process oriented towards the present and future. The concept's consequences were quality of life, survival, acceptance and a peaceful death.Conclusion:This study revealed a strong history of publications on the subject. The analysis of attributes, antecedents and consequences of the concept of hope contributed to understanding its relevance to palliative care nursing and provided suggestions for effective interventions and future research.

Submitted by Ana Moreira (anadsmoreira@ufp.pt) on 2021-11-26T12:51:01Z No. of bitstreams: 1 DM_35409.pdf: 1447467 bytes, checksum: 3f3c3f97b8babf04ca66a9d87b1473fd (MD5) Approved for entry into archive by azevedo@ufp.pt (azevedo@ufp.pt) on 2021-11-26T13:27:57Z (GMT) No. of bitstreams: 1 DM_35409.pdf: 1447467 bytes, checksum: 3f3c3f97b8babf04ca66a9d87b1473fd (MD5) Made available in DSpace on 2021-11-26T13:27:57Z (GMT). No. of bitstreams: 1 DM_35409.pdf: 1447467 bytes, checksum: 3f3c3f97b8babf04ca66a9d87b1473fd (MD5) Previous issue date: 2021-11-19

Microalgae (including cyanobacteria) are the simplest and the most efficient photosynthetic organisms, probably because they have very quick responses and adaptations to environmental stimuli that are not found in any other group of living beings. From phycobiliproteins to carotenoids and to chlorophylls, these organisms have a large range of chromatic compounds related to the photosynthetic metabolism. These microalgae pigments are being exploited for different applications in a variety of industries, from food dyes to health products. Although they appear to have great potential for biotechnological purposes, the use of these products still faces great challenges, like the high cost of production and the instability of the isolated compounds. However, several studies have provided promising prospects for the use of microalgae as a source of pigments by a sustainable bioprocess. The increased demand for natural pigments by consumers and consequently by industry has encouraged the creation of new patents and stimulated the market for these compounds, which has “bloomed” in recent years. Thus, this chapter will cover fundamental aspects of the industrial application of microalgae-based pigments and their economical relevance, the bioprocess optimization for the production of those pigments (e.g., phycocyanin, β-carotene, astaxanthin, and xanthophylls), and highlight the main challenges and future prospects.

Submitted by azevedo@ufp.pt (azevedo@ufp.pt) on 2020-10-30T12:17:28Z No. of bitstreams: 1 PPG_27947.pdf: 531268 bytes, checksum: bdf3cc004df2e3b87d7e78457f1104c0 (MD5) Approved for entry into archive by azevedo@ufp.pt (azevedo@ufp.pt) on 2020-10-30T13:04:43Z (GMT) No. of bitstreams: 1 PPG_27947.pdf: 531268 bytes, checksum: bdf3cc004df2e3b87d7e78457f1104c0 (MD5) Made available in DSpace on 2020-10-30T13:04:44Z (GMT). No. of bitstreams: 1 PPG_27947.pdf: 531268 bytes, checksum: bdf3cc004df2e3b87d7e78457f1104c0 (MD5) Previous issue date: 2019-12-05

Bioactive lipidic compounds of microalgae, such as polyunsaturated fatty acids (PUFA) and carotenoids, can avoid or treat oxidation-associated conditions and diseases like inflammation or cancer. This study aimed to assess the bioactive potential of lipidic extracts obtained from Gloeothece sp.–using Generally Recognized as Safe (GRAS) solvents like ethanol, acetone, hexane:isopropanol (3:2) (HI) and ethyl lactate. The bioactive potential of extracts was assessed in terms of antioxidant (ABTS•+, DPPH•, •NO and O2•assays), anti-inflammatory (HRBC membrane stabilization and Cox-2 screening assay), and antitumor capacity (death by TUNEL, and anti-proliferative by BrdU incorporation assay in AGS cancer cells), while its composition was characterized in terms of carotenoids and fatty acids, by HPLC-DAD and GC-FID methods, respectively. Results revealed a chemopreventive potential of the HI extract owing to its ability to: (I) scavenge -NO• radical (IC50, 1258 ± 0.353 µg·mL−1), (II) inhibit 50% of COX-2 expression at 130.2 ± 7.4 µg·mL−1, (III) protect 61.6 ± 9.2% of lysosomes from heat damage, and (IV) induce AGS cell death by 4.2-fold and avoid its proliferation up to 40% in a concentration of 23.2 ± 1.9 µg·mL−1. Hence, Gloeothece sp. extracts, namely HI, were revealed to have the potential to be used for nutraceutical purposes.

In recent decades, the world has faced increasing demand for energy, namely from fossil sources, which entails great environmental damage. Thus, green fuels with low environmental impact are urgently required, and production of biofuels from organic molecules of macro- and microalgae, such as carbohydrates, proteins, and lipids, is one alternative. However, a problem still remains as what to do with the spent biomass. In this regard, this chapter mainly focuses on how algae can be used as an efficient and economically viable biorefinery feedstock. To reinforce the algal biorefinery concept, a proper connection needs be established between the various input and output streams, as well as services to be provided by the industries involved; because a biorefinery using algae can only be effective through integration with other industries. This chapter is accordingly organized on three pillars: food/feed and nutraceutical applications, biofuel production, and environmental improvement via upgrading of spent biomass.

Summary Intra- and extracellular extracts of thirteen cyanobacteria and twelve microalgae were screened for their activity against a few of the most relevant food-borne pathogens – viz. Salmonella sp., Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus. Strain M2-1 of Scenedesmus obliquus was the microalga that exhibited the highest antibacterial activity, except against Salmonella sp. Although cyanobacteria possessed in general wider antibacterial spectra than microalgae, the former have also been associated with toxin production – and may thus be less useful in food formulation. Nostoc sp. was particularly effective against E. coli and P. aeruginosa, whereas Gloeothece sp. stood out because of its capacity to inhibit all food pathogens tested. Typically, the intracellular extracts were more powerful than their extracellular counterparts; and those with antibacterial features were found to possess high contents of long chain fatty acids – some of which are well-known for their antibacterial activities.

Microalgae are well known for their biotechnological potential, namely with regard to bioactive lipidic components-especially carotenoids and polyunsaturated fatty acids (PUFA), well-known for therapeutic applications based on their antioxidant capacity. The aim of this work was to evaluate the influence of four distinct food-grade solvents upon extractability of specific lipidic components, and on the antioxidant capacity exhibited against both synthetic (2,2-diphenyl-1-picrylhydrazyl (DPPH(•)) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS(+•))) and biological reactive species (O₂(•)⁻ and (•)NO⁻). A eukaryotic microalga (Scenedesmus obliquus (M2-1)) and a prokaryotic one (Gloeothece sp.) were used as case studies. Concerning total antioxidant capacity, the hexane:isopropanol (3:2) and acetone extracts of Sc. obliquus (M2-1) were the most effective against DPPH(•) and ABTS(+•), respectively. Gloeothece sp. ethanol extracts were the most interesting scavengers of O₂(•)⁻, probably due the high content of linolenic acid. On the other hand, acetone and hexane:isopropanol (3:2) extracts were the most interesting ones in (•)NO⁻ assay. Acetone extract exhibited the best results for the ABTS assay, likely associated to its content of carotenoids, in both microalgae. Otherwise, ethanol stood out in PUFA extraction. Therefore, profiles of lipidic components extracted are critical for evaluating the antioxidant performance-which appears to hinge, in particular, on the balance between carotenoids and PUFAs.

A growing market for novel antioxidants obtained from non-expensive sources justifies educated screening of microalgae for their potential antioxidant features. Characterization of the antioxidant profile of 18 species of cyanobacteria (prokaryotic microalgae) and 23 species of (eukaryotic) microalgae is accordingly reported in this paper. The total antioxidant capacity, accounted for by both water- and lipid-soluble antioxidants, was evaluated by the (radical cation) ABTS method. For complementary characterization of cell extracts, a deoxyribose assay was carried out, as well as a bacteriophage P22/Salmonella-mediated approach. The microalga Scenedesmus obliquus strain M2-1 exhibited the highest (p > 0.05) total antioxidant capacity (149 ± 47 AAU) of intracellular extracts. Its scavenger activity correlated well with its protective effects against DNA oxidative damage induced by copper(II)-ascorbic acid; and against decay in bacteriophage infection capacity induced by H 2O2. Finally, performance of an Ames test revealed no mutagenic effects of the said extract.