DCFQE - Comunicações a Conferências / ConferenceItem
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- A alquimia de NemésioPublication . Pavão, Maria Leonor[…]. Da leitura e meditação de Limite de Idade, obra que o próprio autor designou como "delírios microfísicos e biopoéticos", surgem-me claramente como relevantes três observações ou motes de discussão que gostaria de partilhar convosco. […].
- Anti-aging activity of Lobophora variegata ethanolic and methanolic extracts and their fractionsPublication . Rosa, Gonçalo P.; Costa, Ana C.; Medeiros, D.; Seca, Ana M. L.; Barreto, Maria do CarmoSeaweed have promising applications within food, cosmetic and health industries, which led to an increased interest in studying these organisms [1]. In several coastal areas, thousands of tons of macroalgae are cast on beaches and shorelines and it would be very interesting if this biomass could be managed, allowing the extraction of added-value compounds. In this context, polar extracts (methanol and ethanol) of a macroalgal beach cast sample mainly composed of “Lobophora variegate” were prepared and the anti-aging and antioxidant activities were evaluated. The preliminary results showed interesting results, and thus these crude extracts were then fractionated sequentially by their solubility in dichloromethane, acetone and ethyl acetate, resulting in 4 semi-pure fractions each, which were also tested. Fractions A1.1.1 and A1.2.3 were very good tyrosinase inhibitors (IC₅₀ = 37.87 and 24.01 μg/mL, respectively) and fractions A1.1.2 and A1.2.2 presented very good inhibition of elastase (IC₅₀ = 44.76 and 20.86 μg/mL, respectively). However, none of the fractions was active against collagenase. These results show that further purifications of these fractions can lead to the isolation of bioactive added-value compounds.
- Antioxidant activity evaluation from Artemisia gorgonum extractsPublication . Rodrigues, Neidy; Pinto, Diana C. G. A.; Seca, Ana M. L.; Silva, Helena; Pereira, M. LourdesArtemisia gorgonum (Asteraceae) known as “losna or lorna” is used in Cape Verde in traditional medicine to treat inflammation, fever and gastroenteritis. The antioxidant activity of methanol, 70% ethanol, chloroform-methanol and chloroform extracts from A. gorgonum leaves was evaluated using the DPPH assay and the results presented.
- Antioxidant and anticholinesterasic activities of Morella faya (Aiton) Wilbur extractsPublication . Silva, Bruno J. C.; Seca, Ana M. L.; Moreno-Rodriguez, L.; Barreto, Maria do CarmoMorella faya (Aiton) Wilbur (Myricaceae), formerly Myrica faya, is a shrub or small tree native to Macaronesia, Spain and Portugal and invasive in Hawai'i [1]. In the present study, bioactivities of extracts from leaves and bark collected in S. Miguel, Azores, were determined. Extracts were prepared by sequentially extracting the dry material with dichloromethane and acetone at room temperature. The antioxidant activity of the extracts was determined by the DPPH radical scavenging and FeCl3 reduction assays, total phenolics by the Folin-Ciocalteau method and in vitro anticholinesterasic (anti-AChE) activity by a modification of the Ellman method [2]. The dichloromethane extracts did not present any of these activities between 4.9 and 1250 µg/mL. Both acetone extracts presented a high antioxidant activity. For the DPPH scavenging activity, EC50= 17.7 ± 0.13 and 16.9 ± 0.36 µg/mL for leaves and bark, respectively and 4.5 ± 1.1 µg/mL for quercetin (positive control). In the FeCl3reduction assay, EC50 values were 3.8 ± 0.40 and 3.9 ± 0.16 µg/mL for leaves and bark respectively, and 0.995 ± 0.06 µg/mL for gallic acid (positive control). The acetone extracts also showed anti-AChE activity, stronger for the bark, with IC50= 82.9 ± 6.16 µg/mL and weaker for the leaves, with IC50= 333.0 ± 27.3 µg/mL, which are interesting values for whole extracts. Anti-AChE activity was inversely proportional to the amount of phenolic compounds, 639.3 ± 17.8 mg GAE/g of leaf extract and 95.3 ± 6.55 mg GAE/g of bark extract, therefore the compounds responsible for this effect do not belong to this group. The antioxidant activity cannot be explained by the amount of these compounds alone, since it was quite similar for both acetone extracts and did not therefore reflect the differences in polyphenol content.
- Antioxidant markers and cardiovascular risk factors in Azorean subjects with coronary artery diseasePublication . Ferin, Rita; Gomes, Carla; Castro, Ana Rita; Martins, Dinis; Santos, Víctor; Santos, Maria Cristina; Lopes, Paula Alexandra; Baptista, José; Viegas-Crespo, Ana Maria; Pavão, Maria LeonorTo evaluate some blood antioxidant parameters in azorean subjects with coronary artery disease (CAD) previously submitted to percutaneous revascularization (PCI), by considering some cardiovascular risk factors.
- Antitumor activities of invasive allien species from the AzoresPublication . Bettencourt, Ana; Pereira, Joana M.; Costa, Ana C.; Seca, Ana M. L.; Barreto, Maria do Carmo
- Assessment of some atherosclerosis risk factors in apparently healthy subjects from two Azorean populationsPublication . Ferin, Rita; Lima, Manuela; Pavão, Maria LeonorOBJECTIVES: In Azores, the death rate from coronary artery disease (CAD) is about twice than in mainland Portugal. The aim of this study was to assess some major risk factors of atherosclerosis-AT (serum lipid profile and apoB and apoA-1 levels) in subjects from two populations in S. Miguel Island. Hypertension and obesity were also considered. METHODS: The study group was formed by 147 apparently healthy subjects with no chronic diseases, aged 20 to 60 years, born living, respectively, in the villages of Nordeste –ND (53 men and 39 women) and Povoação-PV (22 men and 51 women). Clinical information and life habits were also registered. RESULTS: In both groups about 62% of subjects were hyperlipidemic and 30% obese. Hypertension was observed in about 36% in PV and 43% in the ND group. Both apoB levels and apoB/apoA-1 ratio were significantly higher in ND than in the PV subjects, namely in men (31% and 19%, respectively). Also apoA-1 levels in men were 9% higher in ND than in PV. In the ND group, sex-related differences were found in apoB levels and apoB/apoA-1 ratio, being higher in men. In the PV group, apoA-1 levels were significantly lower (15%) in men than in women. CONCLUSION: Although apparently healthy, most subjects from the two studied populations were hyperlipidemic, mainly due to hypercholesterolemia (TC and LDL-C). However, HDL-C was at high levels (60 mg/dL) in both groups. The coexistence of dyslipidemia, hypertension and obesity (26% of cases in ND and 17% in PV group) can aggravate the risk of developing AT (and CAD), which is higher in ND than in PV, mainly in men. ApoB/apoA-1 ratio revealed to be a simpler index of atherogenic risk than the classic serum lipid profile.
- Bioactive meroditerpenes from Cystoseira abies-marina, collected from the coast of S. Miguel islandPublication . Gouveia, Vera L. M.; Seca, Ana M. L.; Barreto, Maria do Carmo; Silva, Artur M. S.; Kijjoa, AnakeMany substances isolated from marine organisms have demonstrated to possess interesting biological and pharmacological activities and have been used as leads in the development of new pharmaceutical agents. Marine macroalgae are abundant and structuring organisms of the coastal area of all the islands in the Azores Archipelago; some have a markedly seasonal pattern and others are perennial and present during the whole year in the Azorean coasts. One of these is Cystoseira abies-marina which grows abundantly in the coast of the Azores archipelago. Interestingly, it was observed in situ that this alga was not attacked by common predators, such as marine gastropods which led to the suggestion that the great resistance to predation of this species was due to the presence of potentially active compounds, such as antifeedant and/or cytotoxic. Preliminary study on the extracts of Cystoseira abies-marina, collected in S. Miguel Island, showed very promising results for antitumour and antioxidant activities [3]. These results have increased our interest in this alga and led to its phytochemical study. Recently, we have reported the isolation and identification of benzoic acid and two new meronorsesquiterpenes [Cystoazores A (1) and Cystoazores B (2)] from the extracts of this marine alga [4]. Further investigation of this species led to isolation of other two new meroditerpene derivatives (3 and 4). We report here the isolation of the compounds 3 and 4, from Cystoseira abies-marina whose structures were established by 1D and 2D NMR spectral analysis as well as by MS. Additionally, the cytotoxic, anti-inflammatory and antioxidant activities of compounds 1-4 were evaluated and the results will be presented.
- Biomedical applications of Inula speciesPublication . Pinto, Diana C. G. A.; Seca, Ana M. L.; Silva, Artur M. S.The vast genus Inula includes species used in traditional medicine, for the treatment of inflammatory conditions, diabetes, hypertension, and also as bactericides, among other applications. Some corroboration of these ethnopharmacological applications was attempted, for instance crude extracts activity has been evaluated and the main bioactive secondary metabolites have been identified as sesquiterpene lactones. The reported activities include anti-tumour/cytotoxic and anti-inflammatory activity just to mention a few. […].
- Biotechnological conversion of Azorean bovine cheese whey for the production of bio-energyPublication . Rego, E.; Paiva, Lisete S.; Lima, Elisabete; Baptista, JoséThe world's economies, in most countries, are heavily dependent on fossil fuels. This reliance is becoming increasingly problematic taking into account that reserves are rapidly depleting, and no less important is the strong effect of fossil fuel emissions on the global carbon cycle. […].