Percorrer por autor "Marín, Jose J.G."
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- Antioxidant activities of five Lamiaceae plantsPublication . Pereira, Olívia R.; Perez, María J.; Macias, Rócio I.R.; Marín, Jose J.G.; Cardoso, Susana M.In the last decades, oxidative stress has been recognized as a key process in the physiopathology of several diseases. Consequently, the search for new antioxidant compounds, as well as new antioxidant sources, has increased exponentially. The Lamiaceae family encloses many plant species which are potential sources of antioxidant compounds. The present study evaluates the antioxidant activity of phenolic enriched extracts of Lamium album, Leonurus cardiaca, Lavandula dentata, Mentha aquatica and Thymus citriodorus. The antioxidant activity of the hydroethanolic plant extracts was estimated by the in vitro measurement of their 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging potential and reducing power assays. Additionally, the protective effects of the extracts against the potassium dichromate (DK)-induced generation of reactive oxygen species (ROS) in human hepatoblastoma HepG2 cells were measured by flow cytometry, after a 48 h treatment period. The two chemical assays indicated that the extracts possess high antioxidant activity with the order of potency M. aquatica > L. album > L. dentata > T. citriodorus > L. cardiaca. EC50 values ranged from 8.1 to 18.3 μg/mL, and from 51.9 to 94.7 μg/mL for DPPH scavenging and reducing power assays, respectively. Moreover, with the exception of L. cardiaca, at 50 μg/mL, all the extracts induced an effective protection against the DK-induced generation of ROS in HepG2 cells. This protection was approximately 20% and 30%, for DK exposure at 5 and 25μM, respectively. The present data suggest that the herein studied plants can be applied as antioxidant agents.
- Antioxidant activities of five Lamiaceae plantsPublication . Pereira, Olívia R.; Perez, María J.; Macias, Rócio I.R.; Marín, Jose J.G.; Cardoso, Susana M.In the last decades, oxidative stress has been recognized as a key process in the physiopathology of several diseases. Consequently, the search for new antioxidant compounds, as well as new antioxidant sources, has increased exponentially. The Lamiaceae family encloses many plant species which are potential sources of antioxidant compounds. The present study evaluates the antioxidant activity of phenolic enriched extracts of Lamium album, Leonurus cardiaca, Lavandula dentata, Mentha aquatica and Thymus citriodorus. The antioxidant activity of the hydroethanolic plant extracts was estimated by the in vitro measurement of their 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging potential and reducing power assays. Additionally, the protective effects of the extracts against the potassium dichromate (DK)-induced generation of reactive oxygen species (ROS) in human hepatoblastoma HepG2 cells were measured by flow cytometry, after a 48 h treatment period. The two chemical assays indicated that the extracts possess high antioxidant activity with the order of potency M. aquatica > L. album > L. dentata > T. citriodorus > L. cardiaca. EC50 values ranged from 8.1 to 18.3 μg/mL, and from 51.9 to 94.7 μg/mL for DPPH scavenging and reducing power assays, respectively. Moreover, with the exception of L. cardiaca, at 50 μg/mL, all the extracts induced an effective protection against the DK-induced generation of ROS in HepG2 cells. This protection was approximately 20% and 30%, for DK exposure at 5 and 25μM, respectively. The present data suggest that the herein studied plants can be applied as antioxidant agents.
- Antioxidant activities of plants enriched in rosmarinic acidPublication . Pereira, Olívia R.; Perez, María J.; Macias, Rócio I.R.; Domingues, Maria R.M.; Marín, Jose J.G.; Cardoso, Susana M.The present study aims to evaluate the in vitro antioxidant potential of Lavandula dentata and Mentha aquatica plant extracts. For that, ethanolic extracts of the two plants were prepared and their phenolic composition was determined through combined methods of HPLC-DAD and ESI-MS. Moreover, the antioxidant activity of the plant extracts was estimated by: i) evaluation of DPPH scavenging potential and ii) monitoring the protective effects against the generation of reactive oxygen species (ROS) induced by potassium dichromate in human hepatoblastoma HepG2 cells. M. aquatica ethanolic extract was much enriched in phenolic compounds, in comparison with that of L. dentata. Both extracts contained rosmarinic acid in similar concentrations but M. aquatica also contained significant amounts of other phenolics, including rutinoside derivatives of eriodictyol and luteolin. The plant extracts showed high radical scavenging activity against DPPH radical and significantly diminished intracellular ROS production under oxidative stress conditions. The latter protection was mostly evidenced in the L. dentata extract and was also observed for the rosmarinic acid used as reference. Attending that rosmarinic acid is a major phenolic component of L. dentata and M. aquatica ethanolic extracts, the present results suggest that this phenolic compound can be involved in the antioxidant properties of both plants.
- Antioxidant activities of plants enriched in rosmarinic acidPublication . Pereira, Olívia R.; Perez, María J.; Macias, Rócio I.R.; Domingues, Maria R.M.; Marín, Jose J.G.; Cardoso, Susana M.The present study aims to evaluate the in vitro antioxidant potential of Lavandula dentata and Mentha aquatica plant extracts. For that, ethanolic extracts of the two plants were prepared and their phenolic composition was determined through combined methods of HPLC-DAD and ESI-MS. Moreover, the antioxidant activity of the plant extracts was estimated by: i) evaluation of DPPH scavenging potential and ii) monitoring the protective effects against the generation of reactive oxygen species (ROS) induced by potassium dichromate in human hepatoblastoma HepG2 cells. M. aquatica ethanolic extract was much enriched in phenolic compounds, in comparison with that of L. dentata. Both extracts contained rosmarinic acid in similar concentrations but M. aquatica also contained significant amounts of other phenolics, including rutinoside derivatives of eriodictyol and luteolin. The plant extracts showed high radical scavenging activity against DPPH radical and significantly diminished intracellular ROS production under oxidative stress conditions. The latter protection was mostly evidenced in the L. dentata extract and was also observed for the rosmarinic acid used as reference. Attending that rosmarinic acid is a major phenolic component of L. dentata and M. aquatica ethanolic extracts, the present results suggest that this phenolic compound can be involved in the antioxidant properties of both plants.
- Antioxidant activities of plants enriched in rosmarinic acidPublication . Pereira, Olívia R.; Perez, María J.; Macias, Rócio I.R.; Domingues, Maria R.M.; Marín, Jose J.G.; Cardoso, Susana M.The present study aims to evaluate the in vitro antioxidant potential of Lavandula dentata and Mentha aquatica plant extracts. For that, ethanolic extracts of the two plants were prepared and their phenolic composition was determined through combined methods of HPLC-DAD and ESI-MS. Moreover, the antioxidant activity of the plant extracts was estimated by: i) evaluation of DPPH scavenging potential and ii) monitoring the protective effects against the generation of reactive oxygen species (ROS) induced by potassium dichromate in human hepatoblastoma HepG2 cells. M. aquatica ethanolic extract was much enriched in phenolic compounds, in comparison with that of L. dentata. Both extracts contained rosmarinic acid in similar concentrations but M. aquatica also contained significant amounts of other phenolics, including rutinoside derivatives of eriodictyol and luteolin. The plant extracts showed high radical scavenging activity against DPPH radical and significantly diminished intracellular ROS production under oxidative stress conditions. The latter protection was mostly evidenced in the L. dentata extract and was also observed for the rosmarinic acid used as reference. Attending that rosmarinic acid is a major phenolic component of L. dentata and M. aquatica ethanolic extracts, the present results suggest that this phenolic compound can be involved in the antioxidant properties of both plants.
- Antioxidant activity of thymus citriodorusPublication . Pereira, Olívia R.; Perez, María J.; Macias, Rócio I.R.; Marín, Jose J.G.; Cardoso, Susana M.
- Antioxidant activity of thymus citriodorusPublication . Pereira, Olívia R.; Perez, María J.; Macias, Rócio I.R.; Marín, Jose J.G.; Cardoso, Susana M.Background and aims: Thymus citriodorus, or lemon thyme, is used as a medicinal plant in the treatment of asthma and other respiratory diseases, although the mechanism of its beneficial properties is poorly understood. The aim of the present study was to determine the antioxidant ability of the polyphenols present in this plant. Methods: An ethanolic extract was prepared and its antioxidant activity was determined by in vitro measurement of its 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging potential, reducing power, and protective effects against the generation of reactive oxygen species (ROS) induced by potassium dichromate (5 and 25 μM) in hepatoblastoma HepG2 cells. The non-toxic range of extract concentrations was determined by MTT test, after exposure of HepG2 cells to the extract (1–200 µg/mL) for 72 h. ROS generation was measured by flow cytometry using dichlorofluorescein diacetate after 48 h of incubation with the extract. Results and discussion: Concentrations of extract able to decrease to 50% (EC50) DPPH absorbance and reducing power were 0.32±0.05 mg/mL and 0.77±0.15 mg/mL, respectively. These findings indicate that the components of the extract have a relevant radical scavenging ability towards nitrogen free radicals and high reducing capacity. As revealed the MTT test, maximal non-toxic concentration of the extract was 50 µg/mL. This concentration was further used to treat HepG2 cells resulting in a decreased rate of ROS production, both under basal conditions or when oxidative stress was induced by potassium dichromate. Antioxidant protection was approximately 60%. Conclusion: Our results suggest that, since luteolin-7-O-glucoside, apigenin-7-O-glucuronide and rosmarinic acid are major components of Thymus citriodorus ethanolic extract [1], these phenolic constituents may be involved in its antioxidant properties. Accordingly, further investigations to elucidate the actual contribution of each compound to the overall protective effect are needed.
- Cytisus multiflorus: source of antioxidant polyphenolsPublication . Pereira, Olívia R.; Perez, María J.; Macias, Rócio I.R.; Domingues, Maria R.M.; Silva, Artur; Marín, Jose J.G.; Cardoso, Susana M.The present study investigates the phenolic composition and the antioxidant capacity of an ethanolic extract from flowers of C. multiflorus. As determined by HPLC-DAD, ESI-MSn and NMR combined analysis, this extract was mainly composed of chrysin-7-O-β-D-glycopyranoside, and also contained considerable amounts of rutin, a dihydroxyflavone isomer of chrysin and glycosidic derivatives of luteolin and apigenin. The C. multiflorus ethanolic extract exhibited high DPPH scavenging activity and reducing power with EC50 of 13.4 ± 0.6 and 95.7 ± 4.6 µg/mL, respectively. The exposure of human hepatoblastoma HepG2 cells to the non-toxic concentrations of the extract (50 or 200 µg/mL) resulted in a decreased rate of ROS production in a concentration dependent manner. Moreover, the mixture of standards that simulated the phenolic composition of the plant afforded a protection of about 50% in intracellular ROS production. Hence, the gathered results suggest that C. multiflorus polyphenols are closely associated to its antioxidant properties.
- Cytisus multiflorus: source of antioxidant polyphenolsPublication . Pereira, Olívia R.; Perez, María J.; Macias, Rócio I.R.; Domingues, Maria R.M.; Silva, Artur; Marín, Jose J.G.; Cardoso, Susana M.The present study investigates the phenolic composition and the antioxidant capacity of an ethanolic extract from flowers of C. multiflorus. As determined by HPLC-DAD, ESI-MSn and NMR combined analysis, this extract was mainly composed of chrysin-7-O-β-D-glycopyranoside, and also contained considerable amounts of rutin, a dihydroxyflavone isomer of chrysin and glycosidic derivatives of luteolin and apigenin. The C. multiflorus ethanolic extract exhibited high DPPH scavenging activity and reducing power with EC50 of 13.4 ± 0.6 and 95.7 ± 4.6 µg/mL, respectively. The exposure of human hepatoblastoma HepG2 cells to the non-toxic concentrations of the extract (50 or 200 µg/mL) resulted in a decreased rate of ROS production in a concentration dependent manner. Moreover, the mixture of standards that simulated the phenolic composition of the plant afforded a protection of about 50% in intracellular ROS production. Hence, the gathered results suggest that C. multiflorus polyphenols are closely associated to its antioxidant properties.
- Cytisus multiflorus: source of antioxidant polyphenolsPublication . Pereira, Olívia R.; Perez, María J.; Macias, Rócio I.R.; Domingues, Maria R.M.; Silva, Artur; Marín, Jose J.G.; Cardoso, Susana M.The present study investigates the phenolic composition and the antioxidant capacity of an ethanolic extract from flowers of C. multiflorus. As determined by HPLC-DAD, ESI-MSn and NMR combined analysis, this extract was mainly composed of chrysin-7-O-β-D-glycopyranoside, and also contained considerable amounts of rutin, a dihydroxyflavone isomer of chrysin and glycosidic derivatives of luteolin and apigenin. The C. multiflorus ethanolic extract exhibited high DPPH scavenging activity and reducing power with EC50 of 13.4 ± 0.6 and 95.7 ± 4.6 µg/mL, respectively. The exposure of human hepatoblastoma HepG2 cells to the non-toxic concentrations of the extract (50 or 200 µg/mL) resulted in a decreased rate of ROS production in a concentration dependent manner. Moreover, the mixture of standards that simulated the phenolic composition of the plant afforded a protection of about 50% in intracellular ROS production. Hence, the gathered results suggest that C. multiflorus polyphenols are closely associated to its antioxidant properties.