Polyphenols and antioxidant activity in macroalgae from Azores.

International Symposium FloraMac 2010”. Ponta Delgada, Açores, 23-25 de Setembro

Antitumor activity of extracts from Azorean macroalgae.

43rd European Marine Biology Symposium. Ponta Delgada, Açores, 8-12 de Setembro de 2008

Nature through the eyes of chemistry: characterization of novel active molecules from Azorean Natural Products

Jornadas "Ciência nos Açores – que futuro?", Ponta Delgada, 7-8 de Junho de 2013.A área de Química de Produtos Naturais tem contribuído, grandemente, para a descoberta de fármacos e agroquímicos, entre outros, por meio do isolamento de substâncias ativas produzidas por diversos organismos. As novas moléculas têm grande interesse científico, económico, social e farmacológico podendo contribuir, em muito, para a saúde das pessoas e para a sua qualidade de vida. O rastreio de novos compostos com atividade biológica tem sido, recentemente, uma das prioridades da comunidade científica e os Açores, pelas suas características particulares e endemismos assumem particular importância nesta área de investigação. O estudo das potencialidades de plantas e organismos marinhos dos Açores tem sido desenvolvido na Universidade dos Açores/CIRN desde a década de noventa, usando a estratégia de investigação seguinte: (i) seleção dos organismos mais promissores para fins industriais e comerciais pela avaliação da sua atividade em ensaios biológicos diversos, (ii) extração, separação e identificação dos compostos bioativos e (iii) estudos da relação estrutura-atividade dos compostos bioativos isolados.ABSTRACT: The chemistry of Natural Products has contributed greatly to the discovery of pharmaceuticals and agrochemicals agents, among others, by the isolation of active substances produced by various organisms. The new molecules are of great scientific, economic, social and pharmacological importance and may contribute greatly to the people's health and their quality of life. The screening for new compounds with biological activity has been a recent priority for the scientific community and the Azores, by its particular characteristics and endemism is of crucial importance in this area of research. The study of the Azorean plants and marine organisms potential has been investigated in Azores University/CIRN since the '90s decade, using the following research strategy: (i) screening of the most promising organisms for industrial and commercial purposes by evaluating their activity in several biological assays, (ii) extraction, purification and molecular structure elucidation of the bioactive compounds, and (iii) studies of structure-activity relationships of the isolated bioactive compounds

Relação genética entre cepas de Neisseria meningitidis sorogrupo B sorotipo 4

We compared the results obtained by serotyping of PorB epitopes using an expanded panel of monoclonal antibodies (mAb) including mAb 7 and mAb 10, with results obtained by RFLP of rRNA genes (ribotyping). The purpose of this study was to assess the correlation between phenotypic- and genotypic- methods for typing N. meningitidis. The ribotypes obtained using ClaI or EcoRV endonucleases grouped the strains in seven and two different patterns, respectively. This additional characterization of PorB epitopes improved the correlation between these two methods of typing N. meningitidis.Nós comparamos os resultados obtidos pela sorotipagem usando um painel de anticorpos monoclonais (mAb) ao qual se incluíam os mAbs 7 e 10, com os resultados obtidos pelo RFLP do gene rRNA (ribotipagem). O propósito deste estudo foi avaliar a correlação entre os métodos fenotípico e genotípico de tipagem de N. meningitidis. Os ribotipos obtidos usando as endonucleases de restrição ClaI e EcoRV foram hábeis em dividir as cepas em sete e dois diferentes perfis de restrição, respectivamente. A caracterização adicional de epítopos na proteína PorB melhorou a correlação entre os dois métodos de tipagem de N. meningitidis

Caracterização fenotípica e genética de cepas de Bordetella pertussis isoladas em São Paulo, Brasil, 1988-2002

Whooping cough or pertussis was a major cause of childhood morbidity and mortality in the world until the introduction of a whole-cell vaccine in the 1940's. However, since the early 1980's whooping cough cases have increased in many countries, becoming an important problem of public health. This increase may be due to accuracy of laboratory diagnosis and reporting of the disease, a decline in immunity over time, demographic changes, and adaptation of the bacterial population to vaccine-induced immunity. The purpose of this study was to analyze phenotypically and genotypically a collection of 67 Bordetella pertussis isolates recovered during the period 1988-2002 in São Paulo State, Brazil to determine their characteristics and relatedness. All isolates were submitted to susceptibility testing to erythromycin, serotyping, and 56 isolates were analyzed by Pulsed Field Gel Electrophoresis (PFGE). All isolates were susceptible to erythromycin and the majority of them belonged to serotype 1,3. The 56 isolates were classified into 11 PFGE profiles according to the differences in banding patterns. Although more than 60% of the isolates were recovered from patients aged less than three months, almost 15% of them were isolated from adolescents/adults evidencing the increase in the incidence of pertussis among this group of age.A coqueluche ou pertussis foi a maior causa de morbidade e mortalidade infantil em todo o mundo até a introdução de uma vacina na década de 1940. Entretanto, desde a década de 1980, a coqueluche tornou-se, em muitos países , um importante problema de saúde pública. Este acontecimento pode ser atribuído à melhoria do diagnóstico laboratorial e da notificação da doença, declínio da imunidade no decorrer do tempo, mudanças demográficas ou adaptação da população bacteriana à imunidade induzida pela vacina. O objetivo deste estudo foi analisar as características fenotípicas e genotípicas de uma coleção de 67 cepas de Bordetella pertussis isoladas no período 1988-2002 em São Paulo, Brasil. Todas as cepas foram submetidas à determinação do perfil de resistência à eritromicina, à sorotipagem e 56 cepas à eletroforese em campo pulsado (PFGE). Todas as cepas foram sensíveis à eritromicina e a maioria delas pertencia ao sorotipo 1,3. As 56 cepas foram classificadas em 11 perfis de PFGE com base nas diferenças no padrão de bandas. Embora mais de 60% das cepas tenham sido isoladas de crianças com menos de três meses de idade, cerca de 15% delas era de adolescentes/adultos evidenciando um aumento da incidência da coqueluche nesse grupo etário

Macroalgae from S. Miguel Island as a potential source of antiproliferative and antioxidant products

Ulva compressa, Gelidium microdon, Osmundea pinnatifida, Fucus spiralis and Cystoseira abies-marina from the coast of S. Miguel Island were screened for their in vitro cytotoxicity against HeLa tumour cell line, antioxidant potential and total phenolic content. From each alga, the hexane fraction (HF) of the methanol extract, the methanol residue (MF) and the dichloromethane extract (DE), were obtained and evaluated. The highest antiproliferative activity against HeLa cell line was found in C. abies-marina and F. spiralis DE (IC50 8.8 μg/mL and 10.7 μg/mL, respectively), and presented selective cytotoxicity, when tested against Vero cell line. Fluorescence microscopy studies of the two most active extracts suggest an apoptosis-inducing activity. Concerning the antioxidant activity, high values were found on F. spiralis MF and HF (EC50 0.62 μg/mL and 2.01 μg/mL, respectively), even higher than those obtained for trolox and quercetin. This high antioxidant activity in F. spiralis MF can be explained by its content in phenolic compounds, but not for HF, where the antioxidant compounds must be less polar. These results suggest that some macroalgae from the Azorean sea have great potential which could be considered for future applications in medicine, food production or cosmetics industry

Pharmacological activities of Zanthoxylum chiloperone (Rutaceae) extracts

In this work the antinociceptive and anti-inflammatory activities of the extracts of leaves from Zanthoxylum chiloperone were evaluated. The tests were carried out by acetic acid writhing, formalin-induced paw licking, carrageenan-induced rat paw edema and pleurisy methods, using hexane, ethyl acetate and ethanol extracts administered in the doses of 100 and 200 mg/kg. The doses inhibited, significantly, the contortions, the paw lick, the paw edema, the volume of the exsudate and the leukocytes migration. These results suggest that the extracts from Z. chiloperone possess constituents with antinociceptive and anti-inflammatory activities.Neste trabalho foram avaliadas as atividades antinociceptiva e antiinflamatória dos extratos das folhas de Zanthoxylum chiloperone. Os ensaios foram realizados pelos testes de contorções abdominais induzidas por ácido acético, tempo da lambida da pata induzida por formalina, edema de pata e pleurisia induzidas por carragenina, usando os extratos hexânico, em acetato de etila e etanólico administrados nas doses de 100 e 200 mg/kg. As doses testadas reduziram, significativamente, as contorções abdominais, o tempo de lambida da pata, o edema de pata, o volume do exsudato e a migração leucocitária. Estes resultados sugerem que os extratos de Z. chiloperone possuem constituintes com atividades antinociceptiva e antiinflamatória

Efficacy, Stability, and Safety Evaluation of New Polyphenolic Xanthones Towards Identification of Bioactive Compounds to Fight Skin Photoaging

Antioxidants have long been used in the cosmetic industry to prevent skin photoaging, which is mediated by oxidative stress, making the search for new antioxidant compounds highly desirable in this field. Naturally occurring xanthones are polyphenolic compounds that can be found in microorganisms, fungi, lichens, and some higher plants. This class of polyphenols has a privileged scaffold that grants them several biological activities. We have previously identified simple oxygenated xanthones as promising antioxidants and disclosed as hit, 1,2-dihydroxyxanthone (1). Herein, we synthesized and studied the potential of xanthones with different polyoxygenated patterns as skin antiphotoaging ingredients. In the DPPH antioxidant assay, two newly synthesized derivatives showed IC₅₀ values in the same range as ascorbic acid. The synthesized xanthones were discovered to be excellent tyrosinase inhibitors and weak to moderate collagenase and elastase inhibitors but no activity was revealed against hyaluronidase. Their metal-chelating effect (FeCl₃ and CuCl₂) as well as their stability at different pH values were characterized to understand their potential to be used as future cosmetic active agents. Among the synthesized polyoxygenated xanthones, 1,2-dihydroxyxanthone (1) was reinforced as the most promising, exhibiting a dual ability to protect the skin against UV damage by combining antioxidant/metal-chelating properties with UV-filter capacity and revealed to be more stable in the pH range that is close to the pH of the skin. Lastly, the phototoxicity of 1,2-dihydroxyxanthone (1) was evaluated in a human keratinocyte cell line and no phototoxicity was observed in the concentration range tested.This research was supported by national funds through FCT, Foundation for Science and Technology, within the scope of UIDB/04423/2020 and UIDP/04423/2020 under the project PTDC/SAU-PUB/28736/2017 (reference POCI-01-0145-FEDER-028736), cofinanced by COMPETE 2020, Portugal 2020 and the European Union through the ERDF and by FCT through national funds, as well as CHIRALBIOACTIVE-PI-3RL-IINFACTS-2019, and supported by the Applied Molecular Biosciences Unit-UCIBIO which is financed by national funds from FCT/MCTES (UID/Multi/04378/2019). Thanks are also due to FCT, the European Union, QREN, FEDER, COMPETE, by funding cE3c center (Ref. UID/BIA/00329/2019) and Direcao Regional da Ciencia e Tecnologia (Azores Government) by funding Azorean Biodiversity Group.info:eu-repo/semantics/publishedVersio

Physico-chemical characterization of chitosan-based edible films incorporating bioactive compounds of different molecular weight

Chitosan packaging films containing different bioactive compounds (a peptide fraction from whey protein concentrate (WPC) hydrolysate, glycomacropeptide (GMP) and lactoferrin) were produced and their mechanical and barrier properties were evaluated. The molecular weight of protein-based compounds was determined using SDS–PAGE. The addition of GMP and lactoferrin to chitosan film caused a significant reduction of tensile strength and the elongation-at-break significantly increased with the incorporation of lactoferrin. The addition of protein-based compounds also affected gas permeability: a significant decrease in water vapor permeability was observed with the incorporation of lactoferrin; oxygen permeability significantly decreased with the addition of GMP and lactoferrin and carbon dioxide permeability significantly decreased with the incorporation of all of the protein-based compounds. Such results were related with film’s hydrophilicity and crystallinity. This manuscript contributes to the establishment of an approach to optimize edible films performance based on physico-chemical properties, aiming at a higher benefit for the consumer.The authors gratefully acknowledge LoicHilliou for the fruitful discussions on the results and Ana Nicolau for helping in confocal analysis. The present work was supported by the project PTDC/AGR/ALI/67194/2006. The authors M.A. Cerqueira (SFRH/BD/23897/2005), M.C. Avides (SFRH/BPD/26913/2006) and M.A.C. Quintas (SFRH/BPD/41715/2007) were recipient of fellowships from the Fundacaopara a Ciencia e Tecnologia (FCT, Portugal)

Unconstrained mining of transcript data reveals increased alternative splicing complexity in the human transcriptome

Mining massive amounts of transcript data for alternative splicing information is paramount to help understand how the maturation of RNA regulates gene expression. We developed an algorithm to cluster transcript data to annotated genes to detect unannotated splice variants. A higher number of alternatively spliced genes and isoforms were found compared to other alternative splicing databases. Comparison of human and mouse data revealed a marked increase, in human, of splice variants incorporating novel exons and retained introns. Previously unannotated exons were validated by tiling array expression data and shown to correspond preferentially to novel first exons. Retained introns were validated by tiling array and deep sequencing data. The majority of retained introns were shorter than 500 nt and had weak polypyrimidine tracts. A subset of retained introns matching small RNAs and displaying a high GC content suggests a possible coordination between splicing regulation and production of noncoding RNAs. Conservation of unannotated exons and retained introns was higher in horse, dog and cow than in rodents, and 64% of exon sequences were only found in primates. This analysis highlights previously bypassed alternative splice variants, which may be crucial to deciphering more complex pathways of gene regulation in human.info:eu-repo/semantics/publishedVersio