CATAA - Artigos em revistas com arbitragem científica
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Browsing CATAA - Artigos em revistas com arbitragem científica by Author "Antunes, Paulo"
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- Antioxidant and dual dose-dependent antigenotoxic and genotoxic properties of an ethanol extract of propolisPublication . Cruz, Maria Teresa; Antunes, Paulo; Paulo, Luísa; Ferreira, A.M.; Cunha, A.; Aguiar, C. Almeida; Oliveira, RuiPropolis is a resinous product made by honeybees from plant-derived materials, with high content ofpolyphenols associated to several beneficial bioactivities with potential use as a natural food additive forpreservation and as a functional food ingredient. A Portuguese propolis ethanol extract (C.EE) protectedSaccharomyces cerevisiaecells from loss of viability upon exposure to H2O2, both in co- and in pre-incubation experiments. Results obtained with the comet assay suggest that lower concentrations areantigenotoxic while at higher concentrations a genotoxic effect prevails, which correlates with thecytotoxicity of high concentrations of C.EE. Flow cytometry analysis with dichlorofluorescein indicatesthat C.EE induced intracellular antioxidant activityin vivo. Overall the results suggest that C.EE isantigenotoxic but is also toxic at higher concentrations. This dual effect could be explained by thepresence of compounds known to interfere with DNA synthesis and/or cell proliferation, such as caffeicacid phenethyl ester (CAPE) and chrysin, together with antioxidants, like kaempferol, pinobanksin andpinocembrin.
- Major and minor minerals of ‘Sweetheart’ cherry stone from Cova da BeiraPublication . Antunes, Paulo; Pintado, Cristina Miguel; Paulo, LuísaNowadays customers demand objective and trustworthy information about the geographical origin of agricultural products. The mineral composition of agricultural products and its relation with their terroir has been shown to be a useful tool in differentiating commodities produced in a limited region and subjected to certain quality requirements. Cereja da Cova da Beira is the legal term used to denominate cherries produced in the Cova da Beira region (PGI - protected geographical indication) at central eastern part of Portugal, since 1996. In order to establish a methodology to certify its origin, the mineral profile of 'Sweetheart' cherry stone from Cereja da Cova da Beira , was studied. Quantification of major (Ca, Mg, K, P and Na) and minor elements (Cu, Fe Mn and Zn) of stones was carried out by inductively coupled plasma atomic emission spectrometry (ICP-AES). The results showed that, among major elements, Ca was the predominant mineral (1424.62 mg kg-1, dry weight), followed by K and Mg, presenting similar concentrations (1092.17 and 987.55 mg kg-1, respectively), P (271.10 mg kg-1), and Na (24.71 mg kg-1). Regarding micro elements, Mn showed the highest mean value (19.71 mg kg-1), followed by Fe (17.59 mg kg-1), and Cu and Zn with similar levels (7.61 and 6.73 mg kg-1, respectively). On the basis of chemometric pattern recognition procedures, the mineral content of agricultural products and its relation with their area of production can be a useful tool in differentiating commodities produced in a limited region and subjected to certain quality requirements.
- Mineral composition of ‘Sweetheart’ cherry using inductively coupled plasma atomic emission spectroscopyPublication . Paulo, Luísa; Antunes, Paulo; Pintado, Cristina MiguelThere are some investigations regarding the physical and chemical properties of sweet cherry (Prunus avium L.) fruits, mostly their antioxidant capacity, phenol, ascorbic acid, as well as anthocyanin contents. Only little is known about the mineral content of sweet cherries. In this work we studied the 'Sweetheart' cultivar from Cova da Beira (Portugal), as this fruit is a rich source of nutritional components. Therefore, the mineral content of 'Sweetheart' cherry was studied. Inductively coupled plasma atomic emission spectrometry (ICP-AES) was used for the determination of minor and major elements. Prior to ICP-AES measurement, the samples were mineralized with a mixture of HNO3 and H2O2. Based on obtained results the content of minor elements was (Cu) 0.107, (Fe) 0.325, (Mn) 0.204 and (Zn) 0.090 mg 100 g-1. The concentrations of major elements were (Na) 0.629, (Ca) 16.0, (Mg) 24.0, (P) 23.6 and (K) 523 mg 100 g-1. For Mg and K, 'Sweetheart' cherry presented higher concentrations than literature: (Mg) 11.0 and (K) 222 mg 100 g-1. And similar concentrations were assessed for Cu, Fe, Zn, P and Ca: (Cu) 0.060, (Fe) 0.36, (Zn) 0.070, (P) 21.0 and (Ca) 13 mg 100 g-1. The results suggested that 'Sweetheart' cherries are rich in various essential elements, with main emphasis for K and Mg, and might be considered as an important dietary mineral enrichment for individuals deficient in mineral elements.