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Ferreira, Isabel C.f.r. - One of the best experts on this subject based on the ideXlab platform.

  • Wild Roman chamomile extracts and phenolic compounds: enzymatic assays and molecular modelling studies with VEGFR-2 tyrosine kinase
    'Royal Society of Chemistry (RSC)', 2016
    Co-Authors: Guimarães Rafaela, Carvalho, Ana Maria, Queiroz, Maria João R.p., Calhelha, Ricardo C., Froufe, Hugo J.c., Abreu, Rui M.v., Ferreira, Isabel C.f.r.
    Abstract:

    Angiogenesis is a process by which new blood vessels are formed from the pre-existing vasculature, and it is a key process that leads to tumour development. Some studies have recognized phenolic compounds as chemopreventive agents; flavonoids, in particular, seem to suppress the growth of tumor cells modifying the cell cycle. Herein, the antiangiogenic activity of Roman chamomile (Chamaemelum nobile L.) extracts (methanolic extract and infusion) and the main phenolic compounds present (apigenin, apigenin-7-O-glucoside, caffeic acid, chlorogenic acid, luteolin, and luteolin-7-O-glucoside) was evaluated through enzymatic assays using the tyrosine kinase intracellular domain of the Vascular Endothelium Growth Factor Receptor-2 (VEGFR-2), which is a transmembrane receptor expressed fundamentally in endothelial cells involved in angiogenesis, and molecular modelling studies. The methanolic extract showed a lower IC50 value (concentration that provided 50% of VEGFR-2 inhibition) than the infusion, 269 and 301 μg mL(-1), respectively. Regarding phenolic compounds, luteolin and apigenin showed the highest capacity to inhibit the phosphorylation of VEGFR-2, leading us to believe that these compounds are involved in the activity revealed by the methanolic extract.The authors are grateful to strategic projects PEst-OE/AGR/UI0690/2014 and PEst-C/QUI/UI0686/2013-2014 for financial support to the research centres. R. Guimarães, and R. Calhelha thank to FCT, POPH-QREN and FSE for their grants (SFRH/BD/78307/2011 and SFRH/BPD/68344/2010)

  • Inhibition of the VEGFR-2 tyrosine kinase domain by witd Roman chamomile extracts and phenolic compounds
    2015
    Co-Authors: Guimarães Rafaela, Carvalho, Ana Maria, Ferreira, Isabel C.f.r., Calhelha, Ricardo C., Froufe, Hugo J.c., Abreu, Rui M.v., Queiroz, Maria João R.p.
    Abstract:

    Angiogenesis results from new blood vessels growing excessively (e. g. câncer). The Vascular Endothelial Growth Factor (VEGF) is secreted by the tumor cells and plays a crucial role in angiogenesis; low oxygen tension dramatically induces the expression of this major angiogenic factor that when linked to the transmembrane tyrosine kinase receptor VEGFR-2, which is present in endothelial cells, signalizes for the proliferation of these cells towards the tumor. Treatments using small molecules with anti-tyrosine kinase activity (e. g., sorafenib) can block angiogenic signalling, reduce blood tumoral irrigation, and improve chemotherapy distribution [1]. Some studies recognized phenolic compounds as chemopreventive agents, especially flavonoids. Other plant-derived anticancer drugs (e. g. Taxol) proved to be anti-angiogenic. In traditional Chinese medicine, many herbs are used in the treatment of angiogenic diseases such as chronic wounds and rheumatoid arthritis [2]. Furthermore, it has been reported that drinking of green tea could inhibit VEGF-induced angiogenesis in vivo [3]. In the present work, the anti-angiogenic activity of Roman chamomile (Chamaemelum nobile L.) extracts (methanolic extract and infusion) and main phenolic compounds (apigenin, apigenin-7-O-glucoside, caffeic acid, chlorogenic acid, luteolin, luteolin-7-O-glucoside) was evaluated through an enzymatic assay using the VEGFR-2 tyrosine kinase domain. To better understand the inhibition phosphorylation mechanism of the tyrosine kinase receptor by luteolin, apigenin and apigenin-7- 0-glucoside, docking studies were performed. The methanolic extract showed higher phosphorylation inhibition than the infusion (IC50 values of 269 and 301 μg/mL, respectively). Regarding phenolic compounds, luteolin (IC50 2.10 μM) and apigenin (IC50 4.78 μM) were the most potent in inhibiting VEGFR-2 phosphorylation, leading us to believe that these compounds are involved in the anti-angiogenic activity revealed by the methanolic extract

  • Phytochemicals and bioactivity in wild German and Roman chamomiles infusions
    2013
    Co-Authors: Guimarães Rafaela, Barros Lillian, Carvalho, Ana Maria, Queiroz, Maria João R.p., Calhelha, Ricardo C., Ferreira, Isabel C.f.r.
    Abstract:

    Natural matrices represent a rich source of biologically active compounds and are an example of molecular diversity, with recognized potential in drug discovery. In the present work, the infusions of Matricaria recutita L. (German chamomile) and Chamaemelum nobile L. (Roman chamomile) were submitted to an analysis of phenolic compounds and evaluation of bioactivity. Phenolic compounds were characterized by reversed-phase high performance liquid chromatography coupled to diode array detection and mass spectrometry with electron spray ionization (HPLCDAD/ ESI-MS). The bioactivity of the samples was tested in different human tumour cell lines (breast- MCF-7, lung- NCI-H460, colon- HCT -15, cervical- He l a and hepatocellular- HepG2 carcinomas}, and the hepatotoxicity was evaluated using a porcine liver primary cell culture (nontumour cells, PLP2) [1 ,2]. The major compounds found were luteolin 0-acylhexoside in German chamomile, and 5-0-caffeoylquinic acid and an apigenin derivative in Roman chamomile. The highest potential antioxidant activity was showed by German chamomile in all the in vitro assays. Both the infusions showed inhibitory activity of the growth of HCT -15 and He la cell lines, without hepatotoxicity (GI 50>400 μg/ml). Nevertheless, Roman chamomile infusion presented the highest inhibitory activity for all the cell lines (GI50

  • Nutrients, phytochemicals and bioactivity of wild Roman chamomile: a comparison between the herb and its preparations
    'Elsevier BV', 2013
    Co-Authors: Guimarães Rafaela, Barros Lillian, Carvalho, Ana Maria, Queiroz, Maria João R.p., Calhelha, Ricardo C., Dueñas Montserrat, Santos-buelga Celestino, Ferreira, Isabel C.f.r.
    Abstract:

    Roman chamomile, Chamaemelum nobile L. (Asteraceae), has been used for medicinal applications, mainly through oral dosage forms (decoctions and infusions). Herein, the nutritional characterization of C. nobile was performed, and herbal material and its decoction and infusion were submitted to an analysis of phytochemicals and bioactivity evaluation. The antioxidant activity was determined by free radicals scavenging activity, reducing power and inhibition of lipid peroxidation, the antitumour potential was tested in human tumour cell lines (breast, lung, colon, cervical and hepatocellular carcinomas), and the hepatotoxicity was evaluated using a porcine liver primary cell culture. C. nobile proved to be an equilibrated valuable herb rich in carbohydrates and proteins, and poor in fat, providing tocopherols, carotenoids and essential fatty acids (C18:2n6 and C18:3n3). Moreover, the herb and its infusion are a source of phenolic compounds (flavonoids such as flavonols and flavones, phenolic acids and derivatives) and organic acids (oxalic, quinic, malic, citric and fumaric acids) that showed antioxidant and antitumour activities, without hepatotoxicity. The most abundant compounds in the plant extract and infusion were 5-O-caffeoylquinic acid and an apigenin derivative. These, as also other bioactive compounds are affected in C. nobile decoction, leading to a lower antioxidant potential and absence of antitumour potential. The plant bioactivity could be explored in the medicine, food, and cosmetic industries.project PEst-OE/AGR/UI0690/2011 for financial support to CIMO. R. Guimarães, L. Barros and R. Calhelha thanks to FCT, POPH-QREN and FSE for their grants (SFRH/BD/78307/2011, SFRH/BPD/4609/2008 and SFRH/BPD/68344/2010). The GIP-USAL is financially supported by the Consolider-Ingenio 2010 Programme (FUN-C-FOOD, CSD2007-00063). M. Dueñas thanks the Spanish “Ramón y Cajal” Programme for a contract

  • Composição química e propriedades antioxidantes de duas espécies silvestres de camomila do Nordeste de Portugal: camomila-alemã e camomila-romana.
    2012
    Co-Authors: Guimarães Rafaela, Barros Lillian, Carvalho, Ana Maria, Queiroz, Maria João R.p., Ferreira, Isabel C.f.r.
    Abstract:

    Este trabalho teve como objetivo avaliar a composição química e as propriedades antioxidantes de duas espécies de camomila, camomila-alemã (Matricaria recutita) e camomila-romana (Chamaemelum nobile), de forma a comprovar a utilidade do seu uso na medicina tradicional. A composição química das duas espécies foi determinada através da quantificação em açúcares livres (HPLC-RI), ácidos gordos (GC-FID) e tocoferóis (HPLC-fluorescência). A atividade antioxidante foi avaliada através de quatro métodos diferentes: capacidade captadora de radicais DPPH (1,1-difenil-2-picril-hidrazilo), poder redutor, inibição da descoloração do β-caroteno e inibição da peroxidação lipídica em homogeneizados cerebrais de animais pelo ensaio TBARS (espécies reativas do ácido tiobarbitúrico). Assim sendo, este trabalho contribui para a caracterização química das espécies silvestres presentes na flora Transmontana, conferindo-lhe assim um valor acrescentado devido ao potencial antioxidante que apresentam

Guimarães Rafaela - One of the best experts on this subject based on the ideXlab platform.

  • Wild Roman chamomile extracts and phenolic compounds: enzymatic assays and molecular modelling studies with VEGFR-2 tyrosine kinase
    'Royal Society of Chemistry (RSC)', 2016
    Co-Authors: Guimarães Rafaela, Carvalho, Ana Maria, Queiroz, Maria João R.p., Calhelha, Ricardo C., Froufe, Hugo J.c., Abreu, Rui M.v., Ferreira, Isabel C.f.r.
    Abstract:

    Angiogenesis is a process by which new blood vessels are formed from the pre-existing vasculature, and it is a key process that leads to tumour development. Some studies have recognized phenolic compounds as chemopreventive agents; flavonoids, in particular, seem to suppress the growth of tumor cells modifying the cell cycle. Herein, the antiangiogenic activity of Roman chamomile (Chamaemelum nobile L.) extracts (methanolic extract and infusion) and the main phenolic compounds present (apigenin, apigenin-7-O-glucoside, caffeic acid, chlorogenic acid, luteolin, and luteolin-7-O-glucoside) was evaluated through enzymatic assays using the tyrosine kinase intracellular domain of the Vascular Endothelium Growth Factor Receptor-2 (VEGFR-2), which is a transmembrane receptor expressed fundamentally in endothelial cells involved in angiogenesis, and molecular modelling studies. The methanolic extract showed a lower IC50 value (concentration that provided 50% of VEGFR-2 inhibition) than the infusion, 269 and 301 μg mL(-1), respectively. Regarding phenolic compounds, luteolin and apigenin showed the highest capacity to inhibit the phosphorylation of VEGFR-2, leading us to believe that these compounds are involved in the activity revealed by the methanolic extract.The authors are grateful to strategic projects PEst-OE/AGR/UI0690/2014 and PEst-C/QUI/UI0686/2013-2014 for financial support to the research centres. R. Guimarães, and R. Calhelha thank to FCT, POPH-QREN and FSE for their grants (SFRH/BD/78307/2011 and SFRH/BPD/68344/2010)

  • Inhibition of the VEGFR-2 tyrosine kinase domain by witd Roman chamomile extracts and phenolic compounds
    2015
    Co-Authors: Guimarães Rafaela, Carvalho, Ana Maria, Ferreira, Isabel C.f.r., Calhelha, Ricardo C., Froufe, Hugo J.c., Abreu, Rui M.v., Queiroz, Maria João R.p.
    Abstract:

    Angiogenesis results from new blood vessels growing excessively (e. g. câncer). The Vascular Endothelial Growth Factor (VEGF) is secreted by the tumor cells and plays a crucial role in angiogenesis; low oxygen tension dramatically induces the expression of this major angiogenic factor that when linked to the transmembrane tyrosine kinase receptor VEGFR-2, which is present in endothelial cells, signalizes for the proliferation of these cells towards the tumor. Treatments using small molecules with anti-tyrosine kinase activity (e. g., sorafenib) can block angiogenic signalling, reduce blood tumoral irrigation, and improve chemotherapy distribution [1]. Some studies recognized phenolic compounds as chemopreventive agents, especially flavonoids. Other plant-derived anticancer drugs (e. g. Taxol) proved to be anti-angiogenic. In traditional Chinese medicine, many herbs are used in the treatment of angiogenic diseases such as chronic wounds and rheumatoid arthritis [2]. Furthermore, it has been reported that drinking of green tea could inhibit VEGF-induced angiogenesis in vivo [3]. In the present work, the anti-angiogenic activity of Roman chamomile (Chamaemelum nobile L.) extracts (methanolic extract and infusion) and main phenolic compounds (apigenin, apigenin-7-O-glucoside, caffeic acid, chlorogenic acid, luteolin, luteolin-7-O-glucoside) was evaluated through an enzymatic assay using the VEGFR-2 tyrosine kinase domain. To better understand the inhibition phosphorylation mechanism of the tyrosine kinase receptor by luteolin, apigenin and apigenin-7- 0-glucoside, docking studies were performed. The methanolic extract showed higher phosphorylation inhibition than the infusion (IC50 values of 269 and 301 μg/mL, respectively). Regarding phenolic compounds, luteolin (IC50 2.10 μM) and apigenin (IC50 4.78 μM) were the most potent in inhibiting VEGFR-2 phosphorylation, leading us to believe that these compounds are involved in the anti-angiogenic activity revealed by the methanolic extract

  • Phytochemicals and bioactivity in wild German and Roman chamomiles infusions
    2013
    Co-Authors: Guimarães Rafaela, Barros Lillian, Carvalho, Ana Maria, Queiroz, Maria João R.p., Calhelha, Ricardo C., Ferreira, Isabel C.f.r.
    Abstract:

    Natural matrices represent a rich source of biologically active compounds and are an example of molecular diversity, with recognized potential in drug discovery. In the present work, the infusions of Matricaria recutita L. (German chamomile) and Chamaemelum nobile L. (Roman chamomile) were submitted to an analysis of phenolic compounds and evaluation of bioactivity. Phenolic compounds were characterized by reversed-phase high performance liquid chromatography coupled to diode array detection and mass spectrometry with electron spray ionization (HPLCDAD/ ESI-MS). The bioactivity of the samples was tested in different human tumour cell lines (breast- MCF-7, lung- NCI-H460, colon- HCT -15, cervical- He l a and hepatocellular- HepG2 carcinomas}, and the hepatotoxicity was evaluated using a porcine liver primary cell culture (nontumour cells, PLP2) [1 ,2]. The major compounds found were luteolin 0-acylhexoside in German chamomile, and 5-0-caffeoylquinic acid and an apigenin derivative in Roman chamomile. The highest potential antioxidant activity was showed by German chamomile in all the in vitro assays. Both the infusions showed inhibitory activity of the growth of HCT -15 and He la cell lines, without hepatotoxicity (GI 50>400 μg/ml). Nevertheless, Roman chamomile infusion presented the highest inhibitory activity for all the cell lines (GI50

  • Nutrients, phytochemicals and bioactivity of wild Roman chamomile: a comparison between the herb and its preparations
    'Elsevier BV', 2013
    Co-Authors: Guimarães Rafaela, Barros Lillian, Carvalho, Ana Maria, Calhelha, Ricardo C., Dueñas Montserrat, Santos-buelga Celestino, Queiroz, Maria João R. P., Ferreira, Isabel C. F. R.
    Abstract:

    Roman chamomile, Chamaemelum nobile L. (Asteraceae), has been used for medicinal applications, mainly through oral dosage forms (decoctions and infusions). Herein, the nutritional characterisation of C. nobile was performed, and herbal material and its decoction and infusion were submitted to an analysis of phytochemicals and bioactivity evaluation. The antioxidant activity was determined by free radicals scavenging activity, reducing power and inhibition of lipid peroxidation, the antitumour potential was tested in human tumour cell lines (breast, lung, colon, cervical and hepatocellular carcinomas), and the hepatotoxicity was evaluated using a porcine liver primary cell culture. C. nobile proved to be an equilibrated valuable herb rich in carbohydrates and proteins, and poor in fat, providing tocopherols, carotenoids and essential fatty acids (C18:2n6 and C18:3n3). Moreover, the herb and its infusion are a source of phenolic compounds (flavonoids such as flavonols and flavones, phenolic acids and derivatives) and organic acids (oxalic, quinic, malic, citric and fumaric acids) that showed antioxidant and antitumour activities, without hepatotoxicity. The most abundant compounds in the plant extract and infusion were 5-O-caffeoylquinic acid and an apigenin derivative. These, as well as other bioactive compounds, are affected in C. nobile decoction, leading to a lower antioxidant potential and absence of antitumour potential. The plant bioactivity could be explored in the medicine, food, and cosmetic industries.The authors are grateful to strategic project PEst-OE/AGR/UI0690/2011 for financial support to CIMO. R. Guimaraes, L. Barros and R. Calhelha thanks to FCT, POPH-QREN and FSE for their Grants (SFRH/BD/78307/2011, SFRH/BPD/4609/2008 and SFRH/BPD/68344/2010). The GIP-USAL is financially supported by the Consolider-Ingenio 2010 Programme (FUN-C-FOOD, CSD2007-00063). M. Duenas thanks the Spanish "Ramon y Cajal" Programme for a contract

  • Nutrients, phytochemicals and bioactivity of wild Roman chamomile: a comparison between the herb and its preparations
    'Elsevier BV', 2013
    Co-Authors: Guimarães Rafaela, Barros Lillian, Carvalho, Ana Maria, Queiroz, Maria João R.p., Calhelha, Ricardo C., Dueñas Montserrat, Santos-buelga Celestino, Ferreira, Isabel C.f.r.
    Abstract:

    Roman chamomile, Chamaemelum nobile L. (Asteraceae), has been used for medicinal applications, mainly through oral dosage forms (decoctions and infusions). Herein, the nutritional characterization of C. nobile was performed, and herbal material and its decoction and infusion were submitted to an analysis of phytochemicals and bioactivity evaluation. The antioxidant activity was determined by free radicals scavenging activity, reducing power and inhibition of lipid peroxidation, the antitumour potential was tested in human tumour cell lines (breast, lung, colon, cervical and hepatocellular carcinomas), and the hepatotoxicity was evaluated using a porcine liver primary cell culture. C. nobile proved to be an equilibrated valuable herb rich in carbohydrates and proteins, and poor in fat, providing tocopherols, carotenoids and essential fatty acids (C18:2n6 and C18:3n3). Moreover, the herb and its infusion are a source of phenolic compounds (flavonoids such as flavonols and flavones, phenolic acids and derivatives) and organic acids (oxalic, quinic, malic, citric and fumaric acids) that showed antioxidant and antitumour activities, without hepatotoxicity. The most abundant compounds in the plant extract and infusion were 5-O-caffeoylquinic acid and an apigenin derivative. These, as also other bioactive compounds are affected in C. nobile decoction, leading to a lower antioxidant potential and absence of antitumour potential. The plant bioactivity could be explored in the medicine, food, and cosmetic industries.project PEst-OE/AGR/UI0690/2011 for financial support to CIMO. R. Guimarães, L. Barros and R. Calhelha thanks to FCT, POPH-QREN and FSE for their grants (SFRH/BD/78307/2011, SFRH/BPD/4609/2008 and SFRH/BPD/68344/2010). The GIP-USAL is financially supported by the Consolider-Ingenio 2010 Programme (FUN-C-FOOD, CSD2007-00063). M. Dueñas thanks the Spanish “Ramón y Cajal” Programme for a contract

Queiroz, Maria João R.p. - One of the best experts on this subject based on the ideXlab platform.

  • Wild Roman chamomile extracts and phenolic compounds: enzymatic assays and molecular modelling studies with VEGFR-2 tyrosine kinase
    'Royal Society of Chemistry (RSC)', 2016
    Co-Authors: Guimarães Rafaela, Carvalho, Ana Maria, Queiroz, Maria João R.p., Calhelha, Ricardo C., Froufe, Hugo J.c., Abreu, Rui M.v., Ferreira, Isabel C.f.r.
    Abstract:

    Angiogenesis is a process by which new blood vessels are formed from the pre-existing vasculature, and it is a key process that leads to tumour development. Some studies have recognized phenolic compounds as chemopreventive agents; flavonoids, in particular, seem to suppress the growth of tumor cells modifying the cell cycle. Herein, the antiangiogenic activity of Roman chamomile (Chamaemelum nobile L.) extracts (methanolic extract and infusion) and the main phenolic compounds present (apigenin, apigenin-7-O-glucoside, caffeic acid, chlorogenic acid, luteolin, and luteolin-7-O-glucoside) was evaluated through enzymatic assays using the tyrosine kinase intracellular domain of the Vascular Endothelium Growth Factor Receptor-2 (VEGFR-2), which is a transmembrane receptor expressed fundamentally in endothelial cells involved in angiogenesis, and molecular modelling studies. The methanolic extract showed a lower IC50 value (concentration that provided 50% of VEGFR-2 inhibition) than the infusion, 269 and 301 μg mL(-1), respectively. Regarding phenolic compounds, luteolin and apigenin showed the highest capacity to inhibit the phosphorylation of VEGFR-2, leading us to believe that these compounds are involved in the activity revealed by the methanolic extract.The authors are grateful to strategic projects PEst-OE/AGR/UI0690/2014 and PEst-C/QUI/UI0686/2013-2014 for financial support to the research centres. R. Guimarães, and R. Calhelha thank to FCT, POPH-QREN and FSE for their grants (SFRH/BD/78307/2011 and SFRH/BPD/68344/2010)

  • Inhibition of the VEGFR-2 tyrosine kinase domain by witd Roman chamomile extracts and phenolic compounds
    2015
    Co-Authors: Guimarães Rafaela, Carvalho, Ana Maria, Ferreira, Isabel C.f.r., Calhelha, Ricardo C., Froufe, Hugo J.c., Abreu, Rui M.v., Queiroz, Maria João R.p.
    Abstract:

    Angiogenesis results from new blood vessels growing excessively (e. g. câncer). The Vascular Endothelial Growth Factor (VEGF) is secreted by the tumor cells and plays a crucial role in angiogenesis; low oxygen tension dramatically induces the expression of this major angiogenic factor that when linked to the transmembrane tyrosine kinase receptor VEGFR-2, which is present in endothelial cells, signalizes for the proliferation of these cells towards the tumor. Treatments using small molecules with anti-tyrosine kinase activity (e. g., sorafenib) can block angiogenic signalling, reduce blood tumoral irrigation, and improve chemotherapy distribution [1]. Some studies recognized phenolic compounds as chemopreventive agents, especially flavonoids. Other plant-derived anticancer drugs (e. g. Taxol) proved to be anti-angiogenic. In traditional Chinese medicine, many herbs are used in the treatment of angiogenic diseases such as chronic wounds and rheumatoid arthritis [2]. Furthermore, it has been reported that drinking of green tea could inhibit VEGF-induced angiogenesis in vivo [3]. In the present work, the anti-angiogenic activity of Roman chamomile (Chamaemelum nobile L.) extracts (methanolic extract and infusion) and main phenolic compounds (apigenin, apigenin-7-O-glucoside, caffeic acid, chlorogenic acid, luteolin, luteolin-7-O-glucoside) was evaluated through an enzymatic assay using the VEGFR-2 tyrosine kinase domain. To better understand the inhibition phosphorylation mechanism of the tyrosine kinase receptor by luteolin, apigenin and apigenin-7- 0-glucoside, docking studies were performed. The methanolic extract showed higher phosphorylation inhibition than the infusion (IC50 values of 269 and 301 μg/mL, respectively). Regarding phenolic compounds, luteolin (IC50 2.10 μM) and apigenin (IC50 4.78 μM) were the most potent in inhibiting VEGFR-2 phosphorylation, leading us to believe that these compounds are involved in the anti-angiogenic activity revealed by the methanolic extract

  • Phytochemicals and bioactivity in wild German and Roman chamomiles infusions
    2013
    Co-Authors: Guimarães Rafaela, Barros Lillian, Carvalho, Ana Maria, Queiroz, Maria João R.p., Calhelha, Ricardo C., Ferreira, Isabel C.f.r.
    Abstract:

    Natural matrices represent a rich source of biologically active compounds and are an example of molecular diversity, with recognized potential in drug discovery. In the present work, the infusions of Matricaria recutita L. (German chamomile) and Chamaemelum nobile L. (Roman chamomile) were submitted to an analysis of phenolic compounds and evaluation of bioactivity. Phenolic compounds were characterized by reversed-phase high performance liquid chromatography coupled to diode array detection and mass spectrometry with electron spray ionization (HPLCDAD/ ESI-MS). The bioactivity of the samples was tested in different human tumour cell lines (breast- MCF-7, lung- NCI-H460, colon- HCT -15, cervical- He l a and hepatocellular- HepG2 carcinomas}, and the hepatotoxicity was evaluated using a porcine liver primary cell culture (nontumour cells, PLP2) [1 ,2]. The major compounds found were luteolin 0-acylhexoside in German chamomile, and 5-0-caffeoylquinic acid and an apigenin derivative in Roman chamomile. The highest potential antioxidant activity was showed by German chamomile in all the in vitro assays. Both the infusions showed inhibitory activity of the growth of HCT -15 and He la cell lines, without hepatotoxicity (GI 50>400 μg/ml). Nevertheless, Roman chamomile infusion presented the highest inhibitory activity for all the cell lines (GI50

  • Nutrients, phytochemicals and bioactivity of wild Roman chamomile: a comparison between the herb and its preparations
    'Elsevier BV', 2013
    Co-Authors: Guimarães Rafaela, Barros Lillian, Carvalho, Ana Maria, Queiroz, Maria João R.p., Calhelha, Ricardo C., Dueñas Montserrat, Santos-buelga Celestino, Ferreira, Isabel C.f.r.
    Abstract:

    Roman chamomile, Chamaemelum nobile L. (Asteraceae), has been used for medicinal applications, mainly through oral dosage forms (decoctions and infusions). Herein, the nutritional characterization of C. nobile was performed, and herbal material and its decoction and infusion were submitted to an analysis of phytochemicals and bioactivity evaluation. The antioxidant activity was determined by free radicals scavenging activity, reducing power and inhibition of lipid peroxidation, the antitumour potential was tested in human tumour cell lines (breast, lung, colon, cervical and hepatocellular carcinomas), and the hepatotoxicity was evaluated using a porcine liver primary cell culture. C. nobile proved to be an equilibrated valuable herb rich in carbohydrates and proteins, and poor in fat, providing tocopherols, carotenoids and essential fatty acids (C18:2n6 and C18:3n3). Moreover, the herb and its infusion are a source of phenolic compounds (flavonoids such as flavonols and flavones, phenolic acids and derivatives) and organic acids (oxalic, quinic, malic, citric and fumaric acids) that showed antioxidant and antitumour activities, without hepatotoxicity. The most abundant compounds in the plant extract and infusion were 5-O-caffeoylquinic acid and an apigenin derivative. These, as also other bioactive compounds are affected in C. nobile decoction, leading to a lower antioxidant potential and absence of antitumour potential. The plant bioactivity could be explored in the medicine, food, and cosmetic industries.project PEst-OE/AGR/UI0690/2011 for financial support to CIMO. R. Guimarães, L. Barros and R. Calhelha thanks to FCT, POPH-QREN and FSE for their grants (SFRH/BD/78307/2011, SFRH/BPD/4609/2008 and SFRH/BPD/68344/2010). The GIP-USAL is financially supported by the Consolider-Ingenio 2010 Programme (FUN-C-FOOD, CSD2007-00063). M. Dueñas thanks the Spanish “Ramón y Cajal” Programme for a contract

  • Composição química e propriedades antioxidantes de duas espécies silvestres de camomila do Nordeste de Portugal: camomila-alemã e camomila-romana.
    2012
    Co-Authors: Guimarães Rafaela, Barros Lillian, Carvalho, Ana Maria, Queiroz, Maria João R.p., Ferreira, Isabel C.f.r.
    Abstract:

    Este trabalho teve como objetivo avaliar a composição química e as propriedades antioxidantes de duas espécies de camomila, camomila-alemã (Matricaria recutita) e camomila-romana (Chamaemelum nobile), de forma a comprovar a utilidade do seu uso na medicina tradicional. A composição química das duas espécies foi determinada através da quantificação em açúcares livres (HPLC-RI), ácidos gordos (GC-FID) e tocoferóis (HPLC-fluorescência). A atividade antioxidante foi avaliada através de quatro métodos diferentes: capacidade captadora de radicais DPPH (1,1-difenil-2-picril-hidrazilo), poder redutor, inibição da descoloração do β-caroteno e inibição da peroxidação lipídica em homogeneizados cerebrais de animais pelo ensaio TBARS (espécies reativas do ácido tiobarbitúrico). Assim sendo, este trabalho contribui para a caracterização química das espécies silvestres presentes na flora Transmontana, conferindo-lhe assim um valor acrescentado devido ao potencial antioxidante que apresentam

Barros José - One of the best experts on this subject based on the ideXlab platform.

  • Ensaios com herbicida Atlantis em sementeira directa de trigo (2ª parte)
    IFE - Edições e Formação SA, 2008
    Co-Authors: Barros José, Basch G., Carvalho Mário
    Abstract:

    Três anos de ensaios com o herbicida Atlantis na cultura do trigo em sementeira directa, em condições edáficas semelhantes mas condições climáticas diferentes, mostraram claramente que este herbicida é excelente no controlo das infestantes monocotiledóneas Avena sterilis L. (balanco-maior) e Lolium rigidum G. (erva-febra), sendo esta última, uma das infestantes mais problemáticas na cultura estudada. No entanto, e quando a sementeira directa for o sistema de mobilização do solo adoptado pelo agricultor, haverá toda a vantagem em aplicar o herbicida numa fase mais precoce do desenvolvimento destas infestantes (início do afilhamento), pois nesta fase, será possível um óptimo controlo das mesmas, utilizando doses e volumes de calda inferiores aos recomendados e assim, manter a produção potencial da cultura, reduzindo-se os custos de produção e o impacto ambiental que causa a aplicação de produtos químicos, nomeadamente os herbicidas. Relativamente às infestantes dicotiledóneas, poder-se-á afirmar que o Atlantis é um óptimo herbicida para controlar algumas delas, mas mostra-se pouco eficiente no controlo de outras, principalmente quando se aplicam doses inferiores à recomendada pelo fabricante, mesmo na época mais favorável do seu desenvolvimento (2 a 3 pares de folhas). Dentro daquelas mais difíceis de controlar por este herbicida, destacam-se a Polygonum aviculare L. (sempre-noiva) a Chamaemelum mixtum L. (margaça), a Anagallis arvensis L. (morrião), a Silene nocturna L. (cabacinha) e a Daucus carota L. (cenoura-brava). Pelos resultados obtidos poder-se-á afirmar com alguma clareza, que nas mesmas condições em que se realizaram estes ensaios, será possível reduzir as doses de Atlantis e o volume de calda relativamente ao recomendado pelo fabricante, mantendo a produção potencial da cultura. No entanto, sempre que o agricultor pretenda utilizar doses do herbicida inferiores à recomendada deverá recorrer a aconselhamento técnico pois, tanto a densidade de infestantes e o seu estado de desenvolvimento, bem como a sua composição poderão ser muito diversos

  • Controlo de infestantes monocotiledóneas em pós-emergência na cultura do trigo em sementeira directa. Ensaio: Topik
    2006
    Co-Authors: Barros José, Nunes Pedro
    Abstract:

    No ano agrícola de 2005/2006, realizou-se um ensaio cujo objectivo foi estudar o efeito de doses iguais e inferiores às recomendadas de clodinafope + cloquintocete (Topik) no controlo de infestantes monocotiledóneas em pós-emergência e, na produção de trigo de Inverno em sementeira directa. Na área de ensaio onde se aplicou o herbicida, predominavam claramente as monocotiledóneas Lolium rigidum G. (Azevém anual) e a Avena sterilis L As dicotiledóneas mais representativas eram as seguintes: Polygonum aviculare L. (sempre – noiva); Chamaemelum mixtum L. (margaça); Torilis arvensis (Huds) Link (salsinha); Plantago afra L. (plantagro); Galium aparine L. (amor de hortelão); Diplotaxis catholica L. (grizandra); Lactuca serriola L. (alface-brava-menor); Laminum amplexicaule L. (chucapitos); Daucus carota L. (cenoura-brava); Scandix pecten-veneris L. (agulha-de- pastor) e Anagallis arvensis L. (morrião). Os ensaios realizaram-se na herdade da Revilheira, pertença da Direcção Regional de Agricultura do Alentejo (DRAAL) situada no Concelho de Reguengos de Monsaraz. Os resultados obtidos mostram que o herbicida Topik é bastante eficiente no controlo da Avena sterilis L. (balanco-maior) em pós-emergência na cultura do trigo mesmo para doses inferiores às recomendadas, principalmente quando a aplicação do herbicida é efectuada numa fase mais precoce do desenvolvimento da infestante. A eficiência deste herbicida baixa quando a infestante a controlar é o Lolium rigidum G. e as doses utilizadas são inferiores às recomendadas, continuando contudo, a fase mais temporã do desenvolvimento da infestante (início do afilhamento) a ser mais eficaz que a fase mais tardia (afilhamento completo). Uma maior eficiência no controlo das infestantes e um menor período de competição destas com a cultura conduziram para a generalidade dos tratamentos, a uma maior produção de grão quando estas foram efectuadas na fase de início de afilhamento das infestantes (1ª época de aplicação)

  • Controlo de infestantes monocotiledóneas em pós-emergência na cultura do trigo em sementeira directa. Ensaio Topik
    2005
    Co-Authors: Barros José, Fernandes João
    Abstract:

    No ano agrícola de 2004/2005, realizou-se um ensaio cujo objectivo foi estudar o efeito de doses inferiores às recomendadas de clodinafope + cloquintocete (Topik) no controlo de infestantes monocotiledóneas em pós-emergência e, na produção de trigo de Inverno em sementeira directa. Na área de ensaio onde se aplicaram os herbicidas, predominavam claramente as monocotiledóneas Lolium rigidum G. (Azevém anual) e a Avena sterilis L. Outra monocotiledónea que estava presente mas que não foi contabilizada, era o Bromus diandrus R. As dicotiledóneas mais representativas eram as seguintes: Chrysanthemum segetum L. (pampilho-das-searas); Echium plantagineum L. (soagem); Polygonum aviculare L. (sempre – noiva); Raphanus raphanistrum L. (Saramago); Rumex conglomeratus M. (labaça-ordinária); Chamaemelum mixtum L. (margaça); Silene nocturna L. (cabacinha); Calendula arvensis L. (erva-vaqueira) e Stellaria media L. (morugem-branca). Paralelamente, realizou-se outro ensaio onde se estudou o efeito de diversos tratamentos, no controlo das monocotiledóneas. Os ensaios realizaram-se numa herdade privada do Concelho de Évora (Herdade do Louseiro), que dista aproximadamente 10 km desta cidade

  • Controlo de infestantes mono e dicotiledóneas em pós-emergência na cultura do trigo em sementeira directa. Ensaios: Atlantis e Dopler
    2005
    Co-Authors: Barros José, Duarte Vanessa
    Abstract:

    No ano agrícola de 2004/2005, realizaram-se ensaios cujo objectivo foi o de estudar o efeito de doses inferiores às recomendadas de mesosulfurão-metilo & iodosulfurão-metilo & mefenepir-dietilo (Atlantis) no controlo de infestantes mono e dicotiledóneas e diclofope-metilo + fenoxaprope-p-etilo + mefenepir-dietilo (Dopler) no controlo de infestantes monocotiledóneas (Avena sterilis L. e Lolium rigidum G.) em pós-emergência e, na produção de trigo de Inverno em sementeira directa. Na área de ensaio onde se aplicaram os herbicidas, predominavam claramente as monocotiledóneas Lolium rigidum G. (erva-febra) e a Avena sterilis L (balanco-maior). Outra monocotiledónea que estava presente mas que não foi contabilizada, era o Bromus diandrus R (Bromus). As dicotiledóneas mais representativas eram as seguintes: Chrysanthemum segetum L. (pampilho-das-searas); Echium plantagineum L. (soagem); Polygonum aviculare L. (sempre – noiva); Raphanus raphanistrum L. (Saramago); Rumex conglomeratus M. (labaça-ordinária); Chamaemelum mixtum L. (margaça); Silene nocturna L. (cabacinha); Calendula arvensis L. (erva-vaqueira) e Stellaria media L. (morugem-branca). Os ensaios realizaram-se numa herdade privada do Concelho de Évora (Herdade do Louseiro), que dista aproximadamente 10 km desta cidade

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  • Wild Roman chamomile extracts and phenolic compounds: enzymatic assays and molecular modelling studies with VEGFR-2 tyrosine kinase
    'Royal Society of Chemistry (RSC)', 2016
    Co-Authors: Guimarães Rafaela, Carvalho, Ana Maria, Queiroz, Maria João R.p., Calhelha, Ricardo C., Froufe, Hugo J.c., Abreu, Rui M.v., Ferreira, Isabel C.f.r.
    Abstract:

    Angiogenesis is a process by which new blood vessels are formed from the pre-existing vasculature, and it is a key process that leads to tumour development. Some studies have recognized phenolic compounds as chemopreventive agents; flavonoids, in particular, seem to suppress the growth of tumor cells modifying the cell cycle. Herein, the antiangiogenic activity of Roman chamomile (Chamaemelum nobile L.) extracts (methanolic extract and infusion) and the main phenolic compounds present (apigenin, apigenin-7-O-glucoside, caffeic acid, chlorogenic acid, luteolin, and luteolin-7-O-glucoside) was evaluated through enzymatic assays using the tyrosine kinase intracellular domain of the Vascular Endothelium Growth Factor Receptor-2 (VEGFR-2), which is a transmembrane receptor expressed fundamentally in endothelial cells involved in angiogenesis, and molecular modelling studies. The methanolic extract showed a lower IC50 value (concentration that provided 50% of VEGFR-2 inhibition) than the infusion, 269 and 301 μg mL(-1), respectively. Regarding phenolic compounds, luteolin and apigenin showed the highest capacity to inhibit the phosphorylation of VEGFR-2, leading us to believe that these compounds are involved in the activity revealed by the methanolic extract.The authors are grateful to strategic projects PEst-OE/AGR/UI0690/2014 and PEst-C/QUI/UI0686/2013-2014 for financial support to the research centres. R. Guimarães, and R. Calhelha thank to FCT, POPH-QREN and FSE for their grants (SFRH/BD/78307/2011 and SFRH/BPD/68344/2010)

  • Inhibition of the VEGFR-2 tyrosine kinase domain by witd Roman chamomile extracts and phenolic compounds
    2015
    Co-Authors: Guimarães Rafaela, Carvalho, Ana Maria, Ferreira, Isabel C.f.r., Calhelha, Ricardo C., Froufe, Hugo J.c., Abreu, Rui M.v., Queiroz, Maria João R.p.
    Abstract:

    Angiogenesis results from new blood vessels growing excessively (e. g. câncer). The Vascular Endothelial Growth Factor (VEGF) is secreted by the tumor cells and plays a crucial role in angiogenesis; low oxygen tension dramatically induces the expression of this major angiogenic factor that when linked to the transmembrane tyrosine kinase receptor VEGFR-2, which is present in endothelial cells, signalizes for the proliferation of these cells towards the tumor. Treatments using small molecules with anti-tyrosine kinase activity (e. g., sorafenib) can block angiogenic signalling, reduce blood tumoral irrigation, and improve chemotherapy distribution [1]. Some studies recognized phenolic compounds as chemopreventive agents, especially flavonoids. Other plant-derived anticancer drugs (e. g. Taxol) proved to be anti-angiogenic. In traditional Chinese medicine, many herbs are used in the treatment of angiogenic diseases such as chronic wounds and rheumatoid arthritis [2]. Furthermore, it has been reported that drinking of green tea could inhibit VEGF-induced angiogenesis in vivo [3]. In the present work, the anti-angiogenic activity of Roman chamomile (Chamaemelum nobile L.) extracts (methanolic extract and infusion) and main phenolic compounds (apigenin, apigenin-7-O-glucoside, caffeic acid, chlorogenic acid, luteolin, luteolin-7-O-glucoside) was evaluated through an enzymatic assay using the VEGFR-2 tyrosine kinase domain. To better understand the inhibition phosphorylation mechanism of the tyrosine kinase receptor by luteolin, apigenin and apigenin-7- 0-glucoside, docking studies were performed. The methanolic extract showed higher phosphorylation inhibition than the infusion (IC50 values of 269 and 301 μg/mL, respectively). Regarding phenolic compounds, luteolin (IC50 2.10 μM) and apigenin (IC50 4.78 μM) were the most potent in inhibiting VEGFR-2 phosphorylation, leading us to believe that these compounds are involved in the anti-angiogenic activity revealed by the methanolic extract

  • Phytochemicals and bioactivity in wild German and Roman chamomiles infusions
    2013
    Co-Authors: Guimarães Rafaela, Barros Lillian, Carvalho, Ana Maria, Queiroz, Maria João R.p., Calhelha, Ricardo C., Ferreira, Isabel C.f.r.
    Abstract:

    Natural matrices represent a rich source of biologically active compounds and are an example of molecular diversity, with recognized potential in drug discovery. In the present work, the infusions of Matricaria recutita L. (German chamomile) and Chamaemelum nobile L. (Roman chamomile) were submitted to an analysis of phenolic compounds and evaluation of bioactivity. Phenolic compounds were characterized by reversed-phase high performance liquid chromatography coupled to diode array detection and mass spectrometry with electron spray ionization (HPLCDAD/ ESI-MS). The bioactivity of the samples was tested in different human tumour cell lines (breast- MCF-7, lung- NCI-H460, colon- HCT -15, cervical- He l a and hepatocellular- HepG2 carcinomas}, and the hepatotoxicity was evaluated using a porcine liver primary cell culture (nontumour cells, PLP2) [1 ,2]. The major compounds found were luteolin 0-acylhexoside in German chamomile, and 5-0-caffeoylquinic acid and an apigenin derivative in Roman chamomile. The highest potential antioxidant activity was showed by German chamomile in all the in vitro assays. Both the infusions showed inhibitory activity of the growth of HCT -15 and He la cell lines, without hepatotoxicity (GI 50>400 μg/ml). Nevertheless, Roman chamomile infusion presented the highest inhibitory activity for all the cell lines (GI50

  • Nutrients, phytochemicals and bioactivity of wild Roman chamomile: a comparison between the herb and its preparations
    'Elsevier BV', 2013
    Co-Authors: Guimarães Rafaela, Barros Lillian, Carvalho, Ana Maria, Calhelha, Ricardo C., Dueñas Montserrat, Santos-buelga Celestino, Queiroz, Maria João R. P., Ferreira, Isabel C. F. R.
    Abstract:

    Roman chamomile, Chamaemelum nobile L. (Asteraceae), has been used for medicinal applications, mainly through oral dosage forms (decoctions and infusions). Herein, the nutritional characterisation of C. nobile was performed, and herbal material and its decoction and infusion were submitted to an analysis of phytochemicals and bioactivity evaluation. The antioxidant activity was determined by free radicals scavenging activity, reducing power and inhibition of lipid peroxidation, the antitumour potential was tested in human tumour cell lines (breast, lung, colon, cervical and hepatocellular carcinomas), and the hepatotoxicity was evaluated using a porcine liver primary cell culture. C. nobile proved to be an equilibrated valuable herb rich in carbohydrates and proteins, and poor in fat, providing tocopherols, carotenoids and essential fatty acids (C18:2n6 and C18:3n3). Moreover, the herb and its infusion are a source of phenolic compounds (flavonoids such as flavonols and flavones, phenolic acids and derivatives) and organic acids (oxalic, quinic, malic, citric and fumaric acids) that showed antioxidant and antitumour activities, without hepatotoxicity. The most abundant compounds in the plant extract and infusion were 5-O-caffeoylquinic acid and an apigenin derivative. These, as well as other bioactive compounds, are affected in C. nobile decoction, leading to a lower antioxidant potential and absence of antitumour potential. The plant bioactivity could be explored in the medicine, food, and cosmetic industries.The authors are grateful to strategic project PEst-OE/AGR/UI0690/2011 for financial support to CIMO. R. Guimaraes, L. Barros and R. Calhelha thanks to FCT, POPH-QREN and FSE for their Grants (SFRH/BD/78307/2011, SFRH/BPD/4609/2008 and SFRH/BPD/68344/2010). The GIP-USAL is financially supported by the Consolider-Ingenio 2010 Programme (FUN-C-FOOD, CSD2007-00063). M. Duenas thanks the Spanish "Ramon y Cajal" Programme for a contract

  • Nutrients, phytochemicals and bioactivity of wild Roman chamomile: a comparison between the herb and its preparations
    'Elsevier BV', 2013
    Co-Authors: Guimarães Rafaela, Barros Lillian, Carvalho, Ana Maria, Queiroz, Maria João R.p., Calhelha, Ricardo C., Dueñas Montserrat, Santos-buelga Celestino, Ferreira, Isabel C.f.r.
    Abstract:

    Roman chamomile, Chamaemelum nobile L. (Asteraceae), has been used for medicinal applications, mainly through oral dosage forms (decoctions and infusions). Herein, the nutritional characterization of C. nobile was performed, and herbal material and its decoction and infusion were submitted to an analysis of phytochemicals and bioactivity evaluation. The antioxidant activity was determined by free radicals scavenging activity, reducing power and inhibition of lipid peroxidation, the antitumour potential was tested in human tumour cell lines (breast, lung, colon, cervical and hepatocellular carcinomas), and the hepatotoxicity was evaluated using a porcine liver primary cell culture. C. nobile proved to be an equilibrated valuable herb rich in carbohydrates and proteins, and poor in fat, providing tocopherols, carotenoids and essential fatty acids (C18:2n6 and C18:3n3). Moreover, the herb and its infusion are a source of phenolic compounds (flavonoids such as flavonols and flavones, phenolic acids and derivatives) and organic acids (oxalic, quinic, malic, citric and fumaric acids) that showed antioxidant and antitumour activities, without hepatotoxicity. The most abundant compounds in the plant extract and infusion were 5-O-caffeoylquinic acid and an apigenin derivative. These, as also other bioactive compounds are affected in C. nobile decoction, leading to a lower antioxidant potential and absence of antitumour potential. The plant bioactivity could be explored in the medicine, food, and cosmetic industries.project PEst-OE/AGR/UI0690/2011 for financial support to CIMO. R. Guimarães, L. Barros and R. Calhelha thanks to FCT, POPH-QREN and FSE for their grants (SFRH/BD/78307/2011, SFRH/BPD/4609/2008 and SFRH/BPD/68344/2010). The GIP-USAL is financially supported by the Consolider-Ingenio 2010 Programme (FUN-C-FOOD, CSD2007-00063). M. Dueñas thanks the Spanish “Ramón y Cajal” Programme for a contract