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Fucus spiralis is an edible brown seaweed (SW) found in the Portuguese Coast. It has been reported to have high antioxidant activity, which may elicit a potential use for the food industry. However, little information is available on how the SW behaves during the digestive process and how the freeze-drying process might affect the bioaccessibility of the different compounds. Therefore, antioxidant activity, total polyphenols, lipid, and fatty acid contents were measured before and after in vitro simulation of the human digestive process, both in fresh and freeze-dry SW. F. spiralis had a lipid content of 3.49 &plusmn, 0.3% of dry weight (DW), which is a usual amount described for this SW genus. The total lipid bioaccessibility was 12.1 &plusmn, 0.1%. The major omega-3 fatty acid detected was eicosapentaenoic acid, 7.5 &plusmn, 0.1%, with a bioaccessibility percentage of 13.0 &plusmn, 1.0%. Four different methods&mdash, total phenolic content (TPC), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and 1,1-diphenyl-2-picryl-hydrazyl (DPPH)&mdash, were used to assess the antioxidant activity of F. spiralis. The bioaccessibility of the antioxidants studied, ranged between 42.7% and 59.5%, except the bioaccessibility of polyphenols in freeze-dried SW (23.0% &plusmn, 1.0%), suggesting that the freeze-drying process reduces the bioaccessibility of these compounds.

The indiscriminate use of carbapenems in the fight against multidrug resistant Gram-negative bacteria leads to the emergence of resistance to these antimicrobial agents. We examine the in vitro activity of carbapenems and tigecycline against ESBL-producing E. coli and Klebsiella spp. isolated in a single hospital at two different periods eight years apart. Overall resistance to carbapenems ranged from 18.7% in 2007 to 19.1% in 2015/2016. We found no isolates resistant to tigecycline, but two intermediary profiles in the 2015/2016 period. Tigecycline is an important option for treating multidrug resistant Gram-negative infections and helps in the fight against global dissemination of resistance to carbapenems.

Macroalgae‐associated bacteria have already proved to be an interesting source of compounds with therapeutic potential. Accordingly, the main aim of this study was to characterize Asparagopsis armata‐associated bacteria community and evaluate their capacity to produce substances with antitumor and antimicrobial potential. Bacteria were selected according to their phenotype and isolated by the streak plate technique. The identification was carried out by the RNA ribosomal 16s gene amplification through PCR techniques. The antimicrobial activities were evaluated against seven microorganisms (Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Salmonella enteritidis, Staphylococcus aureus, Saccharomyces cerevisiae, Candida albicans) by following their growth through spectrophotometric readings. Antitumor activities were evaluated in vitro on human cell lines derived from hepatocellular (HepG‐2) and breast carcinoma (MCF‐7) using the MTT method. The present work identified a total of 21 bacteria belonging to the genus Vibrio, Staphylococcus, Shewanella, Alteromonadaceae, Bacillus, Cobetia, and Photobacterium, with Vibrio being the most abundant (42.86%). The extract of Shewanella sp. ASP 26 bacterial strain induced the highest antimicrobial activity, namely against Bacillus subtilis and Staphylococcus aureus with an IC 50 of 151.1 and 346.8 μg/mL, respectively. These bacteria (Shewanella sp.) were also the ones with highest antitumor potential, demonstrating antiproliferative activity on HepG‐2 cells. Asparagopsis armata‐associated bacteria revealed to be a potential source of compounds with antitumor and antibacterial activity., Macroalgae‐associated bacteria have showed to be an interesting source of compounds with therapeutic potential. In this study, Asparagopsis armata‐associated bacteria reveal to be a potential source of compounds with antitumor and antibacterial activity.

Cryptococcus gattii has the ability to escape from the host’s immune system through poorly understood mechanisms and can lead to the death of healthy individuals. The role of mannoproteins in C. gattii pathogenicity is not completely understood. The present work characterized a protein, Kpr1, that is essential for the maintenance of C. gattii main virulence factor, the polysaccharide capsule. Our data contribute to the understanding of the role of Kpr1 in capsule structuring, mainly by modulating the distribution of glucans in C. gattii cell wall., The yeast-like pathogen Cryptococcus gattii is an etiological agent of cryptococcosis. The major cryptococcal virulence factor is the polysaccharide capsule, which is composed of glucuronoxylomannan (GXM), galactoxylomannan (GalXM), and mannoproteins (MPs). The GXM and GalXM polysaccharides have been extensively characterized; however, there is little information about the role of mannoproteins in capsule assembly and their participation in yeast pathogenicity. The present study characterized the function of a predicted mannoprotein from C. gattii, designated Krp1. Loss-of-function and gain-of-function mutants were generated, and phenotypes associated with the capsular architecture were evaluated. The null mutant cells were more sensitive to a cell wall stressor that disrupts beta-glucan synthesis. Also, these cells displayed increased GXM release to the culture supernatant than the wild-type strain did. The loss of Krp1 influenced cell-associated cryptococcal polysaccharide thickness and phagocytosis by J774.A1 macrophages in the early hours of interaction, but no difference in virulence in a murine model of cryptococcosis was observed. In addition, recombinant Krp1 was antigenic and differentially recognized by serum from an individual with cryptococcosis, but not with serum from an individual with candidiasis. Taken together, these results indicate that C. gattii Krp1 is important for the cell wall structure, thereby influencing capsule assembly, but is not essential for virulence in vivo. IMPORTANCE Cryptococcus gattii has the ability to escape from the host’s immune system through poorly understood mechanisms and can lead to the death of healthy individuals. The role of mannoproteins in C. gattii pathogenicity is not completely understood. The present work characterized a protein, Kpr1, that is essential for the maintenance of C. gattii main virulence factor, the polysaccharide capsule. Our data contribute to the understanding of the role of Kpr1 in capsule structuring, mainly by modulating the distribution of glucans in C. gattii cell wall.

Methanol, n-hexane and dichloromethane extracts of twelve marine macro-algae (Rhodophyta, Chlorophyta and Heterokontophyta divisions) from Peniche coast (Portugal) were evaluated for their antibacterial and antifungal activity. The antibacterial activity was evaluated by disc diffusion method against Bacillus subtilis (gram positive bacteria) and Escherichia coli (gram negative bacteria). Saccharomyces cerevisiae was used as a model for the antifungal activity by evaluating the growth inhibitory activity of the extracts. The high antibacterial activity was obtained by the Asparagopsis armata methanolic extract (10 mm-0.1 mg/disc), followed by the Sphaerococcus coronopifolius n-hexane extract (8 mm-0.1 mg/disc), and the Asparagopsis armata dichloromethane extract (12 mm-0.3 mg/disc) against Bacillus subtilis. There were no positive results against Escherichia coli. Sphaerococcus coronopifolius revealed high antifungal potential for n-hexane (IC50 = 40.2 µg/ml), dichloromethane (IC50 = 78.9 µg/ml) and methanolic (IC50 = 55.18 µg/ml) extracts against Saccharomyces cerevisiae growth. The antifungal potency of the Sphaerococcus coronopifolius extracts was similar with the standard amphotericin B. Asparagopsis armata and Sphaerococcus coronopifolius reveal to be interesting sources of natural compounds with antimicrobial properties.

This article belongs to the Special Issue Selected Papers from the 14th International Symposium on Marine Natural Products Surface-associated marine bacteria are an interesting source of new secondary metabolites. The aim of this study was the isolation and identification of epiphytic bacteria from the marine brown alga, Bifurcaria bifurcata, and the evaluation of the antioxidant and antimicrobial activity of bacteria extracts. The identification of epiphytic bacteria was determined by 16S rRNA gene sequencing. Bacteria extracts were obtained with methanol and dichloromethane (1:1) extraction. The antioxidant activity of extracts was performed by quantification of total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and oxygen radical absorbance capacity (ORAC). Antimicrobial activities were evaluated against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Salmonella enteritidis, Staphylococcus aureus, Saccharomyces cerevisiae and Candida albicans. A total of 39 Bifurcaria bifurcata-associated bacteria were isolated and 33 were identified as Vibrio sp. (48.72%), Alteromonas sp. (12.82%), Shewanella sp. (12.26%), Serratia sp. (2.56%), Citricoccus sp. (2.56%), Cellulophaga sp. (2.56%), Ruegeria sp. (2.56%) and Staphylococcus sp. (2.56%). Six (15.38%) of the 39 bacteria Bifurcaria bifurcata-associated bacteria presented less than a 90% Basic Local Alignment Search Tool (BLAST) match, and some of those could be new. The highest antioxidant activity and antimicrobial activity (against B. subtilis) was exhibited by strain 16 (Shewanella sp.). Several strains also presented high antimicrobial activity against S. aureus, mainly belonging to Alteromonas sp. and Vibrio sp. There were no positive results against fungi and Gram-negative bacteria. Bifurcaria bifurcata epiphytic bacteria were revealed to be excellent sources of natural antioxidant and antimicrobial compounds.

Acknowledgments : This work was supported through funding provided by the European Commission Collaborative Project FP7 number 265896-www.bammbo.eu). One of the authors (G.C.) was partially supported by CNRS (Côte d’Azur delegation-DR 20). J.-M. Guigonis from the Plate-Forme Bernard Rossi of Nice is acknowledged for recording HRMS spectra. Cancer and infectious diseases continue to be a major public health problem, and new drugs are necessary. As marine organisms are well known to provide a wide range of original compounds, the aim of this study was to investigate the bioactivity of the main constituents of the cosmopolitan red alga, Sphaerococcus coronopifolius. The structure of several bromoditerpenes was determined by extensive spectroscopic analysis and comparison with literature data. Five molecules were isolated and characterized which include a new brominated diterpene belonging to the rare dactylomelane family and named sphaerodactylomelol (1), along with four already known sphaerane bromoditerpenes (2–5). Antitumor activity was assessed by cytotoxicity and anti-proliferative assays on an in vitro model of human hepatocellular carcinoma (HepG-2 cells). Antimicrobial activity was evaluated against four pathogenic microorganisms: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans. Compound 4 exhibited the highest antimicrobial activity against S. aureus (IC50 6.35 μM) and compound 5 the highest anti-proliferative activity on HepG-2 cells (IC50 42.9 μM). The new diterpene, sphaerodactylomelol (1), induced inhibition of cell proliferation (IC50 280 μM) and cytotoxicity (IC50 720 μM) on HepG-2 cells and showed antimicrobial activity against S. aureus (IC50 96.3 μM). info:eu-repo/semantics/publishedVersion

Neste estudo estimou-se a distribuição e prevalência de β-lactamases de espectro estendido pertencentes às famílias TEM, SHV e CTX-M entre amostras de Escherichia coli e Klebsiella spp. no Hospital Universitário de Santa Maria, Rio Grande do Sul. Durante 14 meses, 90 microrganismos foram selecionados como prováveis produtores de ESBL. Os isolados foram submetidos a testes fenotípicos confirmatórios para a presença de ESBL. A seguir, os tipos de ESBLs presentes em cada microrganismo foram determinados através da pesquisa dos respectivos genes através da reação em cadeia da polimerase. Empregando-se o método do disco combinado, a presença de ESBLs foi confirmada em 55 (61,1%) amostras; quando o método do duplo disco foi utilizado, 57 (63,3%) amostras foramprodutoras de ESBLs. Com base na PCR, as ESBLs do tipo TEM e SHV foram mais presentes em Klebsiella pneumoniae enquanto que ESBL do tipo CTX-M foram mais presentes em Klebsiella oxytoca.

The purpose of the present study was to evaluate the identification of 19 Brazilian C. dubliniensis based on the biochemical profile exhibited when tested by the commercial identification kit ID 32C (bioMerieux). Thirteen of the isolates were rigorously identified as C. dubliniensis and the remaining isolates (six) were considered as having a doubtful profile but the software also suggested that there was 83.6% of chances for them to be C. dubliniensis. As well as pointed by the literature the identification obtained by phenotypic tests should be considered presumptive for C. dubliniensis due to variability of this new species. Dezenove culturas de C. dubliniensis isoladas no Brasil, previamente identificadas através de métodos genotípicos, foram avaliadas pelo kit comercial ID 32C (bioMerieux). Treze culturas foram identificadas como C. dubliniensis, mas as demais (seis) evidenciaram perfil duvidoso, embora o software do sistema sugerisse 83,6% de chances das mesmas pertencerem à espécie C. dubliniensis. A literatura tem registrado grande variabilidade fenotípica com esta espécie e, por isto, as identificações obtidas com este sistema deverão ser consideradas como presuntivas.

Cryptococcus neoformans is a pathogenic fungus that causes life-threatening meningoencephalitis in immunocompromised patients (HIV-positive patients), and lymphoproliferative disorders in patients subjected to organ transplantation and other immunosuppressive therapies. This fungus is commonly found in soil and avian excreta, mainly from pigeon and turkey. We describe the isolation and characterization of 17 clinical and 10 environmental (pigeon excreta) isolates from the Brazilian state Rio Grande do Sul. We analyzed capsule formation, carbon assimilation pattern, canavanine-glycine-bromothymol blue (CGB) reaction, and nitrate and urease tests, as well as susceptibility to antifungal drugs. The genetic variability among C. neoformans isolates was studied using randomly amplified polymorphic DNA (RAPD) analysis. Eight of 22 arbitrary polymerase chain reaction primers used confirmed genetic polymorphism among the environmental isolates tested, suggesting that it remains feasible to use RAPD analysis as a typing method. Three of the selected primers yielded 10 molecular subclasses. The majority of the clinical isolates were assigned to the molecular subclass F. The RAPD data obtained reinforce the developing consensus about the population structure of this fungus.

Este estudo foi realizado com os primeiros isolados ambientais de C. neoformans sorotipo D, obtidos no Rio Grande Susceptibility of C. neoformans to heat and antifungal agents 5 do Sul. Objetivando-se avaliar a susceptibilidade a agentes antifúngicos de forma mais rigorosa, utilizou-se a técnica de referência proposta pelo NCCLS, Caldo Yeast Nitrogen Base (YNB) proposto por Ghannoum et al., Antibiotic medium 3, caldo YNB adequado à metodologia do NCCLS e o E-test. Os resultados indicaram que todos os isolados foram sensíveis à anfotericina B (0,0625 -0,5 μg/mL), fluconazol (0,125 – 4,0 μg/ mL), itraconazol (0,031 – 0,25 μg/ml) e fluorocitosina (0,125-4,0 μg/mL) através das técnicas empregadas. Nos testes de termotolerância (47ºC/30 min), observou-se que as culturas de C. neoformans sorotipo D são mais sensíveis do que as de C. neoformans sorotipo A. In this work we studied the susceptibility to heat and antifungal agents of the first strains of environmental Cryptococcus neoformans var neoformans (serotype D) isolated in the state of Rio Grande do Sul, Brazil. In order to achieve a rigorous analysis, we employed the methodology recommended by NCCLS, Yeast Nitrogen Base (YNB) proposed by Ghannoum et al (YNB-1), Antibiotic medium 3 (AM3) indicated by others, YNB adjusted to the NCCLS methodology (YNB-2) and Etest. Our results indicate that all strains were susceptible to amphotericin B (0.0625 – 0.5 μg/mL), fluconazole (0.125 – 8.0 μg/mL), itraconazole (0.031 – 0.25 μg/mL) and flucytosine (0.125 – 4.0 μg/mL). The C. neoformans serotype D strains were more susceptible to heat (47ºC / 30 min) than C. neoformans serotype A.