Chemical composition and anti-diabetic properties of Cytisus multiflorus

Bakground and aims: The interest on plants with potential medicinal properties has been increasing worldwide. In the Iberian Peninsula there are some endemic species known by the population for their pharmacologic activity with valorization potential that have not been yet characterized. The white Spanish broom (Cytisus multiflorus) is described as having anti-diabetic effect [1] and in a preliminary the hypoglycemic and hyper-insulinemic effect of an aqueous extract has been shown [2]. The aim of this work was to fractionate and analyse the composition of the aqueous extract of C. multiflorus flowering parts and evaluate its potential as an anti-diabetic agent. Materials and methods: The aqueous extract was primarily fractionated by SPE using water:methanol (W:Me) eluent (a 10% step-wise gradient W:Me from 100:0 to 0:100) followed by high performance liquid chromatography with diode array detector (HPLC-DAD). The most relevant fraction were analysed by LC-MS to determine the chemical composition. Total fenol content was determined by a modified Folin-Ciocalteau method and the anti-oxidant activity was evaluated by the DPPH mehod. Finally, the hipoglicemic potential was evaluated in vivo using glucose intolerant rats (GIR). Results: Eleven fractions of the bulk extract were obtained. Seven of these fractions (10, 30, 40, 50, 60, 70 e 80% Me) were found to have a relevant compounds, mostly flavonoid compounds, namely, rutin (50, 60 and 70% Me fractions), ferrulic acid (30% Me), referred as having hypoglicemic effect. The fractions obtained with 50 and 70% Me showed the highest content in phenol equivalents and the highest anti-oxidant effect were found in the 50 and 60% Me fractions. The 30 and 60% Me fraction had no effect on the post-prandial glicemia. Conclusions: The 30, 50, 60 and 70% Me fractions, due to their chemical composition and anti-oxidant effects were the most promising to have anti-diabetic effect. However, the 30 and 60% Me were found to be ineffective. The 50% Me fraction showed both a high content of flavonoid compounds and the highest anti-oxidant power which suggest that it may constitute the most promising one. The anti-diabetic properties of this fraction should be investigated. [1] Camejo-Rodrigues J. et al. (2003). J. Ethnopharmacol, 89, 199-209 [2] Célia M. Antunes, Laurinda R. Areias, Inês P. Vieira, Ana C. Costa, M. Teresa Tinoco, & Júlio Cruz-Morais (2009). Rev. Fitoterapia 9 (Supl.1): 91

Some elements concentrations of Corallina elongata from São Miguel (Azores) under different environmental conditions.

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

Modificações na concha de lapas em fontes hidrotermais de superfície

Copyright © 2012 APRH.Os organismos calcários são conhecidos por serem sensíveis à água do mar acidificada, e têm sido apontados como potenciais sentinelas para estudos sobre acidificação do oceano. As lapas estão entre os organismos que caracterizam a zona intertidal e nos Açores, podendo também ser encontradas em locais com actividade hidrotermal de superfície, onde a acidez da água do mar na proximidade das fontes hidrotermais é naturalmente mais elevada devido à liberação de CO2. Durante uma visita ocasional para avaliar a ocorrência e abundância de algas no intertidal encontraram-se vários espécimes de Patella candei gomesii (Patellidae) com conchas aberrantes, na proximidade de fontes hidrotermais. Estes indivíduos, colectados sob tais condições exibiam conchas frágeis, quase transparentes, com espessura muito reduzida.ABSTRACT: Calcareous organisms are known to be sensitive to acidified seawater, and they have been reported as potential sentinels for ocean acidification studies. Limpets are among the organisms that characterise intertidal zones, and in the Azores can also be found at sites with shallow water hydrothermal activity, where the acidity of seawater in the vicinity of hydrothermal vents is naturally higher due to CO2 release. During an occasional intertidal survey on the occurrence and abundance of intertidal algae we found limpets with abnormal shells, and specimens of Patella candei gomesii (Patellidae) collected under such conditions exhibited weak and almost transparent shells with reduced shell thickness

Investigating natural acidified marine environments

Jornadas "Ciência nos Açores – que futuro?", Ponta Delgada, 7-8 de Junho de 2013.As fontes hidrotermais de superfície constituem laboratórios naturais para investigar ambientes marinhos naturalmente acidificados como modelos para a avaliação dos efeitos da acidificação dos oceanos. Os organismos nestas zonas estão sujeitos às condições acídicas, bem como às variações de temperatura e exposição a produtos químicos, incluindo a libertação de metais pesados. Ambientes extremos podem promover alterações nas comunidades, organismos ou processos fisiológicos. Algumas das estratégias, mecanismos, adaptações ou até mesmo especiação (novas espécies) poderiam mostrar como viver nesses ambientes e ajudar a descobrir organismos suficientemente sensíveis para atuar como sentinelas (bioindicadores) e, eventualmente adaptações biológicas associadas com potencial uso biotecnológico. Algumas espécies, devido à sua estrutura calcária (sensíveis a condições ácidas) requerem uma atenção especial. As fontes hidrotermais de superfície são uma característica peculiar dos Açores. Representam ambientes únicos e constituem patrimônio natural do litoral dos Açores. No presente projeto pretende-se investigar os efeitos da atividade hidrotermal em comunidades subtidais macrobentónicas em São Miguel, com uma abordagem inovadora no estudo dos efeitos da acidificação dos oceanos. A comparação entre locais com atividade hidrotermal e locais sem atividade hidrotermal irá fornecer informações sobre as diferenças na distribuição das espécies. Esta informação será complementada com a investigação sobre as respostas de organismos selecionados aos efeitos de viver sob a influência das fontes hidrotermais.ABSTRACT: Shallow water hydrothermal vents constitute natural laboratories to investigate natural acidified marine environments as models for the evaluation of the effects of ocean acidification. Organisms at those areas are subject to acidic conditions, as well as to temperature variations and exposure to chemicals, including the release of heavy metals. The extreme environment can promote changes on the communities, organisms or physiological processes. Some of the strategies, mechanisms, adaptations or even speciation (new species) could show how to live in these environments and help discovering organisms sufficiently sensitive to act as early sentinels (bioindicators) and possible associated biological adaptations with potential biotechnological use. Some species, due to their calcareous structure (sensitive to acidic conditions) need special attention. Shallow water hydrothermal vents are striking features of the Azores. They represent unique environments and constitute a natural patrimony of the Azorean coastline. In the present project we investigate the effects of hydrothermal activity on subtidal macrobenthic communities in the island of São Miguel, in an innovative approach to study ocean acidification effects. A comparison between sites with hydrothermal activity and sites without hydrothermal activity will provide information on species distribution differences. This information will be complemented with research on the responses of selected organisms to the effects of living under the vents influence

Drought response of cowpea (Vigna unguiculata (L.) Walp.) landraces at leaf physiological and metabolite profile levels

Drought threatens the world’s food production, particularly in Sub Saharan Africa low external input and rain fed agricultural systems, where cowpea (Vigna unguiculata (L.) Walp.) is an important food crop. In the context of growing concerns regarding climate changes implications on water availability, this study aimed at 1) to evaluate the drought responses in cowpea landraces with contrasting drought tolerance levels (A55 – high sensitivity; A80 - mild sensitivity; A116 - tolerant), 2) using an integrated physiological (leaf gas exchanges; chlorophyll a fluorescence) and biochemical (photoprotective pigments; RuBisCO activity; primary metabolite profiling) analysis to identify drought tolerance probes, in plants submitted to three water availability levels (well-watered, WW; mild drought, MD; severe drought, SD). A116 plants maintained a better water status under drought, what could justify the higher Pn and Pnmax values in MD, as well as higher photochemical use of energy (reflected in the photochemical quenching (qL) and in the quantum yield of non-cyclic electron transport (Y(II))), and the lower need of photoprotective thermal dissipation mechanisms (given by the non-photochemical quenching (qN), and the quantum yield of regulated energy dissipation at photosystem PSII (Y(NPQ))), in MD and SD plants. Greater declines of net (Pn) and potential (Pnmax) photosynthesis were observed in A55 plants, which frequently showed significant impacts already under MD conditions in most parameters, whereas A80 usually displayed and intermediate behaviour. Still, even A55 showed some acclimation response, regarding photoprotective mechanisms associated with high contents of zeaxanthin, lutein, and carotenes, and high Y(NPQ), and qN values, supporting the absence of an increase in the non-regulated energy dissipation at PSII (Y(NO) did not increased) even in SD plants. Additionally, A55 was not significantly affected in RuBisCO activity, which showed to be quite resilient in cowpea. A primary metabolite profiling, complemented with a partial least square discrimination analysis (PLS-DA), allowed a better separation of A116 and A55 plants according to their degree of drought tolerance. In response to drought, A116 showed the greatest accumulation of most responsive metabolites, 14 in total, with sucrose, fucose, urea, alanine and putrescine being exclusively increased in this genotype, suggesting that they can be candidates as drought tolerance proxies. Other compounds, as proline, valine, isoleucine (among amino acids), and rhamnose and raffinose (among sugars) showed close increase patternsinfo:eu-repo/semantics/publishedVersio

Los moluscos del cesped algal intermareale en Azores

The molluscan fauna of the high intertidal algal turf on the island of Pico (Azores) was studied in order to complement existing descriptions of the intertidal biota on these islands. A total of 15,275 specimens belonging to 19 species were found. Five species, the gastropods Alvania mediolittoralis Gofas, 1989, Omalogyra atomus (Philippi, 1841), Pisinna glabrata (Megerle von Muhlfeld, 1824) and Skeneopsis planorbis (Fabricius 0., 1780), and the bivalve Lasaea adansoni (Gmelin, 1791), account for 98% of the total number of specimens, P. glabrata itself being responsible for 46% of all specimens. In places where patellid limpets are absent, Ihe algal turf extends higher in the intertidal zone. In such places, three very abundant molluscan species characterize molluscan assemblages in the algal turf: Lasaea adansoni, Skeneopsis planorbis and Pisinna glabrata, Lasaeo adansoni and Skeneopsis planorbis virtually disappear in the transition from algal lurf to algal fronds, the only (very) abundant species being P. glabrata and, with less importance, Omalogyra atomus and Sinezona cingulata (Costa O.G., 1861)

Efficacy of phage-antibiotic combination therapy for the control of P. aeruginosa biofilms in vitro

Pseudomonas aeruginosa is regarded a “phenomenon of bacterial resistance”. This gram negative bacterium is responsible for 65% of mortality in the hospitals all over the world and its prevalence can be a consequence of important reasons: intrinsic resistance determined by virulence factors; acquired resistance mechanisms that lead to a low susceptibility to antimicrobial agents; and the ability of P. aeruginosa to grow in any natural and artificial surfaces leading to the development of biofilms. The emergence of new strategies to control P. aeruginosa biofilms is becoming more evident due to their resistance to traditional treatments and bacteriophages have been recognized as an attractive alternative for this problem. Nevertheless, despite the potential of phages as antimicrobial agents, it is well known that bacteria can quickly adapt and create new survival strategies and the emergence of phage-resistant phenotypes is inevitable. Thus, the combination of phage and antibiotic therapies could have potentially more benefits than just using phages and antibiotics alone. This work describes the synergy between different P. aeruginosa phages (phiIBB-PAP21, phiIBB-PAP1, phiIBB-PAC23 and phiIBB-PAA2) and antibiotics (amikacin, ciprofloxacin, piperacillin and tetracycline) against planktonic cultures and biofilms. The efficacy of phages and antibiotics were evaluated by the enumeration of viable cells and the determination of biofilm biomass, or by the measurement of absorbance (OD600nm) in the case of planktonic cultures. In biofilms, the individual use of phage phiIBB-PAP21 and amikacin resulted in a reduction in the number of viable cells of 1.3 and 1.76 log, respectively, while the combination therapy of both resulted in approximately 3.66 log reduction. In the case of phages used together with ciprofloxacin the biofilm eradication was total. A possible explanation for this behaviour lies on the disruption of the biofilm matrix induced by some of the phages which can enhance the antibiotic penetration and availability to the cells. Nevertheless more studies are in progress to disclose this synergistic behaviour