2020 |
Herrera, B A; Bruna, T C; Sierpe, R A; Lang, E P; Urzúa, M; Flores, M I; Jara, P; Yutronic, N A Surface Functionalized with Per-(6-Amino-6-Deoxy)-Β-Cyclodextrin for Potential Organic Pollutant Removal from Water Artículo de revista Carbohydrate Polymers, 233 (7), pp. 115865, 2020, ISSN: 0144-8617. Resumen | Enlaces | BibTeX | Etiquetas: activity, calculations, cyclodextrin, Surface Functionalized @article{RN75, title = {A Surface Functionalized with Per-(6-Amino-6-Deoxy)-Β-Cyclodextrin for Potential Organic Pollutant Removal from Water}, author = {B A Herrera and T C Bruna and R A Sierpe and E P Lang and M. Urz\'{u}a and M I Flores and P. Jara and N. Yutronic}, url = {http://www.sciencedirect.com/science/article/pii/S0144861720300394}, doi = {https://doi.org/10.1016/j.carbpol.2020.115865}, issn = {0144-8617}, year = {2020}, date = {2020-01-01}, journal = {Carbohydrate Polymers}, volume = {233}, number = {7}, pages = {115865}, publisher = {2012 Elsevier Inc.}, abstract = {In this work, we present a solid silicon substrate functionalized with modified β-cyclodextrin monolayers as an optimal surface for organic contaminant uptake. The inclusion and capture of three potential pollutants, 4-chlorophenoxyacetic acid, 4-aminobenzoic acid and phenylethylamine, were studied. 1H-NMR and ROESY studies revealed the complete inclusion and details of the conformational orientation of the three guests in the per-(6-amino-6-deoxy)-β-cyclodextrin matrix, forming three new inclusion complexes that have not yet been reported. Capture assays for the guests were carried out by immersing the substrates in an aqueous pollutant solution and by measuring the UV\textendashvis spectra. This substrate showed a high sorption capacity at equilibrium, between 2.5 × 10−5 and 6.0 × 10−5 mmol/substrate, for the studied pollutants. In addition, this surface can be reused four times with an efficiency equal to the initial use. Therefore, it could be a versatile platform that could be applied for the capture of other organic pollutants from water.}, keywords = {activity, calculations, cyclodextrin, Surface Functionalized}, pubstate = {published}, tppubtype = {article} } In this work, we present a solid silicon substrate functionalized with modified β-cyclodextrin monolayers as an optimal surface for organic contaminant uptake. The inclusion and capture of three potential pollutants, 4-chlorophenoxyacetic acid, 4-aminobenzoic acid and phenylethylamine, were studied. 1H-NMR and ROESY studies revealed the complete inclusion and details of the conformational orientation of the three guests in the per-(6-amino-6-deoxy)-β-cyclodextrin matrix, forming three new inclusion complexes that have not yet been reported. Capture assays for the guests were carried out by immersing the substrates in an aqueous pollutant solution and by measuring the UV–vis spectra. This substrate showed a high sorption capacity at equilibrium, between 2.5 × 10−5 and 6.0 × 10−5 mmol/substrate, for the studied pollutants. In addition, this surface can be reused four times with an efficiency equal to the initial use. Therefore, it could be a versatile platform that could be applied for the capture of other organic pollutants from water. |
2018 |
Fuentes-Barros, G; Castro-Saavedra, S; Liberona, L; Acevedo-Fuentes, W; Tirapegui, C; Mattar, C; Cassels, B K Variation of the Alkaloid Content of Peumus Boldus (Boldo) Artículo de revista Fitoterapia, 127 , pp. 179-185, 2018, ISSN: 0367-326x. Resumen | Enlaces | BibTeX | Etiquetas: activity, alkaloids, antioxidant boldine, boldus, herbal in-vitro, inhibition, leaves, medicine, peumus peumus-boldus, phenanthrene phytochemistry, plants, products, reticuline traditional uhplc-ms/ms @article{RN386, title = {Variation of the Alkaloid Content of Peumus Boldus (Boldo)}, author = { G. Fuentes-Barros and S. Castro-Saavedra and L. Liberona and W. Acevedo-Fuentes and C. Tirapegui and C. Mattar and B.K. Cassels}, url = {/brokenurl#<Go to ISI>://WOS:000437551000027}, doi = {10.1016/j.fitote.2018.02.020}, issn = {0367-326x}, year = {2018}, date = {2018-01-01}, journal = {Fitoterapia}, volume = {127}, pages = {179-185}, abstract = {Eighteen alkaloids were detected in the bark, leaves, wood and roots of Peumus boldus, including traces of secoboldine, N-methylsecoboldine (boldine methine), glaucine and norreticuline, not reported previously as constituents of this species. Using appropriate standards, we quantified thirteen of them by UHPLC-MS/MS. Boldine was dominant in the bark, and laurolitsine in wood and roots. The alkaloid composition of the leaves, determined for 130 individually identified trees, classified by age and sex, was highly variable, where N-methyllaurotetanine, laurotetanine, coclaurine and in some cases isocorydine predominated, but not boldine.}, keywords = {activity, alkaloids, antioxidant boldine, boldus, herbal in-vitro, inhibition, leaves, medicine, peumus peumus-boldus, phenanthrene phytochemistry, plants, products, reticuline traditional uhplc-ms/ms}, pubstate = {published}, tppubtype = {article} } Eighteen alkaloids were detected in the bark, leaves, wood and roots of Peumus boldus, including traces of secoboldine, N-methylsecoboldine (boldine methine), glaucine and norreticuline, not reported previously as constituents of this species. Using appropriate standards, we quantified thirteen of them by UHPLC-MS/MS. Boldine was dominant in the bark, and laurolitsine in wood and roots. The alkaloid composition of the leaves, determined for 130 individually identified trees, classified by age and sex, was highly variable, where N-methyllaurotetanine, laurotetanine, coclaurine and in some cases isocorydine predominated, but not boldine. |
2017 |
Aguirre, P; Garcia-Beltran, O; Tapia, V; Munoz, Y; Cassels, B K; Nunez, M Neuroprotective Effect of a New 7,8-Dihydroxycoumarin-Based Fe2+/Cu2+ Chelator in Cell and Animal Models of Parkinson's Disease Artículo de revista Acs Chemical Neuroscience, 8 (1), pp. 178-185, 2017, ISSN: 1948-7193. Resumen | Enlaces | BibTeX | Etiquetas: activity, antioxidant antioxidant, basal brain chelator, complex content, coumarin-based coumarins, disease, ganglia, i, inhibitory-activity, iron iron-copper lipid-peroxidation, model, mouse neurodegeneration neurodegeneration, neuroprotection, niptp oxidative parkinsons stress, with @article{RN346, title = {Neuroprotective Effect of a New 7,8-Dihydroxycoumarin-Based Fe2+/Cu2+ Chelator in Cell and Animal Models of Parkinson's Disease}, author = { P. Aguirre and O. Garcia-Beltran and V. Tapia and Y. Munoz and B.K. Cassels and M. Nunez}, url = {/brokenurl#<Go to ISI>://WOS:000392459400021}, doi = {10.1021/acschemneuro.6b00309}, issn = {1948-7193}, year = {2017}, date = {2017-01-01}, journal = {Acs Chemical Neuroscience}, volume = {8}, number = {1}, pages = {178-185}, abstract = {Disturbed iron homeostasis, often coupled to mitochondrial dysfunction, plays an important role in the progression of common neurodegenerative diseases such as Parkinson's disease (PD). Recent studies have underlined the relevance of iron chelation therapy for the treatment of these diseases. Here we describe the synthesis, chemical, and biological characterization of the multifunctional chelator 7,8-dihydroxy-4-((methylamino)methyl)-2H-chromen-2-one (DHC12). Metal selectivity of DHC12 was Cu2+ similar to Fe2+ > Zn2+ > Fe3+. No binding capacity was detected for Hg2+, co(2+), ca(2+), Mnz+, Mg2+, Ni2+, Pb2+ or Cd2+. DHC12 accessed cells colocalizing with Mitotracker Orange, an indication of mitochondrial targeting. In addition, DHC12 chelated mitochondrial and cytoplasmic labile iron. Upon mitochondrial complex I inhibition, DHC12 protected plasma membrane and mitochondria against lipid peroxidation, as detected by the reduced formation of 4-hydroxynonenal adducts and oxidation of C11-BODIPY581/891. DHC12 also blocked the decrease in mitochondrial membrane potential, detected by tetrarnethylrhodamine distribution. DHC12 inhibited MAO-A and MAO-B activity. Oral administration of DHC12 to mice (0.25 mg/kg body weight) protected substantia nigra pars compacta (SNpc) neurons against MPTP-induced death. Taken together, our results support the concept that DHC12 is a mitochondrial-targeted neuroprotective iron-copper chelator and MAO-B inhibitor with potent antioxidant and mitochondria protective activities. Oral administration of low doses of DHC12 is a promising therapeutic strategy for the treatment of diseases with a mitochondrial iron accumulation component, such as PD.}, keywords = {activity, antioxidant antioxidant, basal brain chelator, complex content, coumarin-based coumarins, disease, ganglia, i, inhibitory-activity, iron iron-copper lipid-peroxidation, model, mouse neurodegeneration neurodegeneration, neuroprotection, niptp oxidative parkinsons stress, with}, pubstate = {published}, tppubtype = {article} } Disturbed iron homeostasis, often coupled to mitochondrial dysfunction, plays an important role in the progression of common neurodegenerative diseases such as Parkinson's disease (PD). Recent studies have underlined the relevance of iron chelation therapy for the treatment of these diseases. Here we describe the synthesis, chemical, and biological characterization of the multifunctional chelator 7,8-dihydroxy-4-((methylamino)methyl)-2H-chromen-2-one (DHC12). Metal selectivity of DHC12 was Cu2+ similar to Fe2+ > Zn2+ > Fe3+. No binding capacity was detected for Hg2+, co(2+), ca(2+), Mnz+, Mg2+, Ni2+, Pb2+ or Cd2+. DHC12 accessed cells colocalizing with Mitotracker Orange, an indication of mitochondrial targeting. In addition, DHC12 chelated mitochondrial and cytoplasmic labile iron. Upon mitochondrial complex I inhibition, DHC12 protected plasma membrane and mitochondria against lipid peroxidation, as detected by the reduced formation of 4-hydroxynonenal adducts and oxidation of C11-BODIPY581/891. DHC12 also blocked the decrease in mitochondrial membrane potential, detected by tetrarnethylrhodamine distribution. DHC12 inhibited MAO-A and MAO-B activity. Oral administration of DHC12 to mice (0.25 mg/kg body weight) protected substantia nigra pars compacta (SNpc) neurons against MPTP-induced death. Taken together, our results support the concept that DHC12 is a mitochondrial-targeted neuroprotective iron-copper chelator and MAO-B inhibitor with potent antioxidant and mitochondria protective activities. Oral administration of low doses of DHC12 is a promising therapeutic strategy for the treatment of diseases with a mitochondrial iron accumulation component, such as PD. |
Asela, I; Noyong, M; Simon, U; Andrades-Lagos, J; Campanini-Salinas, J; Vasquez-Velasquez, D; Kogan, M; Yutronic, N; Sierpe, R Gold Nanoparticles Stabilized with Beta Cyclodextrin-2-Amino-4-(4-Chlorophenyl)Thiazole Complex: A Novel System for Drug Transport Artículo de revista Plos One, 12 (10), 2017, ISSN: 1932-6203. Resumen | Enlaces | BibTeX | Etiquetas: activity, beta-cyclodextrin, complexes, delivery-systems, inclusion organophosphorus pesticides, photodegradation rates, thiazoles @article{RN353, title = {Gold Nanoparticles Stabilized with Beta Cyclodextrin-2-Amino-4-(4-Chlorophenyl)Thiazole Complex: A Novel System for Drug Transport}, author = { I. Asela and M. Noyong and U. Simon and J. Andrades-Lagos and J. Campanini-Salinas and D. Vasquez-Velasquez and M. Kogan and N. Yutronic and R. Sierpe}, url = {/brokenurl#<Go to ISI>://WOS:000412754400038}, doi = {10.1371/journal.pone.0185652}, issn = {1932-6203}, year = {2017}, date = {2017-01-01}, journal = {Plos One}, volume = {12}, number = {10}, abstract = {While 2-amino-4-(4-chlorophenyl)thiazole (AT) drug and thiazole derivatives have several biological applications, these compounds present some drawbacks, such as low aqueous solubility and instability. A new complex of beta CD-AT has been synthesized to increase AT solubility and has been used as a substrate for the deposit of solid-state AuNPs via magnetron sputtering, thus forming the beta CD-AT-AuNPs ternary system, which is stable in solution. Complex formation has been confirmed through powder X-ray diffraction and 1D and 2D nuclear magnetic resonance. Importantly, the amine and sulfide groups of AT remained exposed and can interact with the surfaces of the AuNPs. The complex association constant (970 M-1) has been determined using phase solubility analysis. AuNPs formation (32 nm average diameter) has been studied by UV-Visible spectroscopy, transmission/scanning electron microscopy and energy-dispersive X-ray analysis. The in vitro permeability assays show that effective permeability of AT increased using beta CD. In contrast, the ternary system did not have the capacity to diffuse through the membrane. Nevertheless, the antibacterial assays have demonstrated that AT is transferred from beta CD-AT-AuNPs, being available to exert its antibacterial activity. In conclusion, this novel beta CD-AT-AuNPs ternary system is a promising alternative to improve the delivery of AT drugs in therapy.}, keywords = {activity, beta-cyclodextrin, complexes, delivery-systems, inclusion organophosphorus pesticides, photodegradation rates, thiazoles}, pubstate = {published}, tppubtype = {article} } While 2-amino-4-(4-chlorophenyl)thiazole (AT) drug and thiazole derivatives have several biological applications, these compounds present some drawbacks, such as low aqueous solubility and instability. A new complex of beta CD-AT has been synthesized to increase AT solubility and has been used as a substrate for the deposit of solid-state AuNPs via magnetron sputtering, thus forming the beta CD-AT-AuNPs ternary system, which is stable in solution. Complex formation has been confirmed through powder X-ray diffraction and 1D and 2D nuclear magnetic resonance. Importantly, the amine and sulfide groups of AT remained exposed and can interact with the surfaces of the AuNPs. The complex association constant (970 M-1) has been determined using phase solubility analysis. AuNPs formation (32 nm average diameter) has been studied by UV-Visible spectroscopy, transmission/scanning electron microscopy and energy-dispersive X-ray analysis. The in vitro permeability assays show that effective permeability of AT increased using beta CD. In contrast, the ternary system did not have the capacity to diffuse through the membrane. Nevertheless, the antibacterial assays have demonstrated that AT is transferred from beta CD-AT-AuNPs, being available to exert its antibacterial activity. In conclusion, this novel beta CD-AT-AuNPs ternary system is a promising alternative to improve the delivery of AT drugs in therapy. |
Martinez-Cifuentes, M; Weiss-Lopez, B; Araya-Maturana, R Theoretical Study About the Effect of Halogen Substitution on the Reactivity of Antitumor 3-Formylchromones and Their Free Radicals Artículo de revista Journal of Chemistry, 10.1155/2017/9254831 , 2017, ISSN: 2090-9063. Resumen | Enlaces | BibTeX | Etiquetas: activity, antidiabetic antioxidants, chromone, chromonyl-2, derivatives, flavonoids, in-vitro, inhibitors polyphenolic respiration, tumor-cell @article{RN373, title = {Theoretical Study About the Effect of Halogen Substitution on the Reactivity of Antitumor 3-Formylchromones and Their Free Radicals}, author = { M. Martinez-Cifuentes and B. Weiss-Lopez and R. Araya-Maturana}, url = {/brokenurl#<Go to ISI>://WOS:000396251800001}, doi = {10.1155/2017/9254831}, issn = {2090-9063}, year = {2017}, date = {2017-01-01}, journal = {Journal of Chemistry}, volume = {10.1155/2017/9254831}, abstract = {The mandatory presence of a chlorine atom on the aromatic ring of 6-hydroxy-3-formyl angular chromones, on the respiration inhibition of mammary carcinoma mouse, is explained through a computational study of these compounds. This study analyzes the reactivity of the neutral molecules and their free radicals, in gas phase and with water solvation, incorporated by the polarizable continuum medium (PCM) approach. Electrophilic reactivities were evaluated using Fukui (f(+)) and Parr (P+) functions. The stabilities of radical species formed by the abstraction of a hydrogen atom from the O-H bond were evaluated by bond dissociation enthalpy (BDE) and spin density (SD) calculations. This study has potential implications for the design of chromone analogues as anticancer compounds.}, keywords = {activity, antidiabetic antioxidants, chromone, chromonyl-2, derivatives, flavonoids, in-vitro, inhibitors polyphenolic respiration, tumor-cell}, pubstate = {published}, tppubtype = {article} } The mandatory presence of a chlorine atom on the aromatic ring of 6-hydroxy-3-formyl angular chromones, on the respiration inhibition of mammary carcinoma mouse, is explained through a computational study of these compounds. This study analyzes the reactivity of the neutral molecules and their free radicals, in gas phase and with water solvation, incorporated by the polarizable continuum medium (PCM) approach. Electrophilic reactivities were evaluated using Fukui (f(+)) and Parr (P+) functions. The stabilities of radical species formed by the abstraction of a hydrogen atom from the O-H bond were evaluated by bond dissociation enthalpy (BDE) and spin density (SD) calculations. This study has potential implications for the design of chromone analogues as anticancer compounds. |
2016 |
Simirgiotis, M J; Quispe, C; Borquez, J; Areche, C; Sepulveda, B Molecules, 21 (1), 2016, ISSN: 1420-3049. Resumen | Enlaces | BibTeX | Etiquetas: activity, antioxidant capacity, chile, chilean de esi-ms, flavonoids, fruits, hplc-dad, ms/ms, northern orbitrap parts pascua, pda, pears, pera phenolics, proanthocyanidins, products, uhplc-ms @article{RN289, title = {Fast Detection of Phenolic Compounds in Extracts of Easter Pears (Pyrus Communis) from the Atacama Desert by Ultrahigh-Performance Liquid Chromatography and Mass Spectrometry (Uhplc-Q/Orbitrap/Ms/Ms)}, author = { M.J. Simirgiotis and C. Quispe and J. Borquez and C. Areche and B. Sepulveda}, url = {/brokenurl#<Go to ISI>://WOS:000369486800014}, doi = {10.3390/molecules21010092}, issn = {1420-3049}, year = {2016}, date = {2016-01-01}, journal = {Molecules}, volume = {21}, number = {1}, abstract = {A small Chilean variety of pears growing in the town of Toconao, an oasis located at the northeastern edge of the Salar de Atacama, northern Chile, was studied by means of modern PDA and high resolution mass spectral data (UHPLC-PDA-HESI-orbitrap-MS/MS). In addition, the antioxidant features of the fruits were compared with the varieties Packhman's Triumph and Abate Fetel and correlated with the presence of phenolic compounds. The non-pigmented phenolics were fingerprinted and related to the antioxidant capacities measured by the bleaching of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and total content of phenolics and flavonoids measured by spectroscopic methods. The machine allowed a fast separation of 15 min employing a flow rate of 1 mL per minute and could accurately identify 25 compounds, including several isorhamnetin derivatives and phenolic acids, present in the peel and pulps of this Chilean variety for the first time. The compounds were monitored using a wavelength range of 210-800 nm. The native small Chilean pear showed the highest antioxidant activity measured as the bleaching of the DPPH radical, the ferric reducing antioxidant power and superoxide anion scavenging activity (8.61 +/- 0.65 g/mL, 712.63 +/- 12.12 micromols trolox equivalents (mol/TE)/100 g FW, and 82.89% +/- 2.52% at 100 g/mL, respectively).}, keywords = {activity, antioxidant capacity, chile, chilean de esi-ms, flavonoids, fruits, hplc-dad, ms/ms, northern orbitrap parts pascua, pda, pears, pera phenolics, proanthocyanidins, products, uhplc-ms}, pubstate = {published}, tppubtype = {article} } A small Chilean variety of pears growing in the town of Toconao, an oasis located at the northeastern edge of the Salar de Atacama, northern Chile, was studied by means of modern PDA and high resolution mass spectral data (UHPLC-PDA-HESI-orbitrap-MS/MS). In addition, the antioxidant features of the fruits were compared with the varieties Packhman's Triumph and Abate Fetel and correlated with the presence of phenolic compounds. The non-pigmented phenolics were fingerprinted and related to the antioxidant capacities measured by the bleaching of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and total content of phenolics and flavonoids measured by spectroscopic methods. The machine allowed a fast separation of 15 min employing a flow rate of 1 mL per minute and could accurately identify 25 compounds, including several isorhamnetin derivatives and phenolic acids, present in the peel and pulps of this Chilean variety for the first time. The compounds were monitored using a wavelength range of 210-800 nm. The native small Chilean pear showed the highest antioxidant activity measured as the bleaching of the DPPH radical, the ferric reducing antioxidant power and superoxide anion scavenging activity (8.61 +/- 0.65 g/mL, 712.63 +/- 12.12 micromols trolox equivalents (mol/TE)/100 g FW, and 82.89% +/- 2.52% at 100 g/mL, respectively). |
Jara-Bermeo, A; Penailillo, P; San-Martin, A; Malagon, O; Gilardoni, G; Gutierrez, M Chemical Composition and Antibacterial Activity of Essential Oils from Azorella Spinosa (Apiaceae) against Wild Phytopathogenic Bacteria Artículo de revista Journal of the Chilean Chemical Society, 61 (4), pp. 3246-3249, 2016, ISSN: 0717-9707. Resumen | Enlaces | BibTeX | Etiquetas: activity, antimicrobial antimicrobialactivity, antioxidant, azorella compacta, essential extracts, lamiaceae, oils, plant spinosa, thymus-vulgaris, umbelliferae @article{RN284, title = {Chemical Composition and Antibacterial Activity of Essential Oils from Azorella Spinosa (Apiaceae) against Wild Phytopathogenic Bacteria}, author = { A. Jara-Bermeo and P. Penailillo and A. San-Martin and O. Malagon and G. Gilardoni and M. Gutierrez}, url = {/brokenurl#<Go to ISI>://WOS:000393079900019}, doi = {10.4067/S0717-97072016000400019}, issn = {0717-9707}, year = {2016}, date = {2016-01-01}, journal = {Journal of the Chilean Chemical Society}, volume = {61}, number = {4}, pages = {3246-3249}, abstract = {The aim of the present investigation was to appraise variation in the chemical composition and antimicrobial activity against phytopatogenic bacterial of essential oils from Azorella spinosa. Three samples of A. spinosa were collected in different date in the same area. The essential oils were obtained for hydrodestillation using a Clevenger-type apparatus. The chemical composition of essential oils were analysed using Gas chromatography-mass spectrometry showed variation in the yield and composition, the main detected compounds were monoterpenes such as limonene (10.66-12.30%), tricyclene (10.81-16.99%) and sabinene (9.10-11.49%), the most abundant sesquiterpene was gamma-gurjenene (5.48-8.47%). The biological activity of essential oils from A. spinosa against wild phytopatogenic microorganisms showed selectivity over Pseudomonas syringae. This is the first report of the essential oil composition of A. spinosa, and confirms that natural products obtained from aromatic plants represent an important source of bioactive molecules that could be used as new alternatives for the treatment of phytopatogenic bacteria infections.}, keywords = {activity, antimicrobial antimicrobialactivity, antioxidant, azorella compacta, essential extracts, lamiaceae, oils, plant spinosa, thymus-vulgaris, umbelliferae}, pubstate = {published}, tppubtype = {article} } The aim of the present investigation was to appraise variation in the chemical composition and antimicrobial activity against phytopatogenic bacterial of essential oils from Azorella spinosa. Three samples of A. spinosa were collected in different date in the same area. The essential oils were obtained for hydrodestillation using a Clevenger-type apparatus. The chemical composition of essential oils were analysed using Gas chromatography-mass spectrometry showed variation in the yield and composition, the main detected compounds were monoterpenes such as limonene (10.66-12.30%), tricyclene (10.81-16.99%) and sabinene (9.10-11.49%), the most abundant sesquiterpene was gamma-gurjenene (5.48-8.47%). The biological activity of essential oils from A. spinosa against wild phytopatogenic microorganisms showed selectivity over Pseudomonas syringae. This is the first report of the essential oil composition of A. spinosa, and confirms that natural products obtained from aromatic plants represent an important source of bioactive molecules that could be used as new alternatives for the treatment of phytopatogenic bacteria infections. |
2015 |
Areche, C; Benites, J; Cornejo, A; Ruiz, L M; Garcia-Beltran, O; Simirgiotis, M J; Sepulveda, B Seco-Taondiol, an Unusual Meroterpenoid from the Chilean Seaweed Stypopodium Flabelliforme and Its Gastroprotective Effect in Mouse Model Artículo de revista Marine Drugs, 13 (4), pp. 1726-1738, 2015, ISSN: 1660-3397. Resumen | Enlaces | BibTeX | Etiquetas: activity, algae, antiproliferative cytoprotection defense, epitaondiol, isoepitaondiol, meroditerpenoids, mucosal natural-products, zonale @article{RN238, title = {Seco-Taondiol, an Unusual Meroterpenoid from the Chilean Seaweed Stypopodium Flabelliforme and Its Gastroprotective Effect in Mouse Model}, author = { C. Areche and J. Benites and A. Cornejo and L.M. Ruiz and O. Garcia-Beltran and M.J. Simirgiotis and B. Sepulveda}, url = {/brokenurl#<Go to ISI>://WOS:000353715900008}, doi = {10.3390/md13041726}, issn = {1660-3397}, year = {2015}, date = {2015-01-01}, journal = {Marine Drugs}, volume = {13}, number = {4}, pages = {1726-1738}, abstract = {Ten known meroterpenoids and the new meroterpenoid 7 were isolated from the Chilean seaweed Stypopodium flabelliforme as their acetylated derivatives. Furthermore, the known metabolite taondiol has been isolated for the first time from this species. The molecular structure of the new metabolite was determined by spectroscopic methods based on 1D- and 2D-NMR. Isolation of 7 represents a keywords step toward a better understanding of the biogenesis of this class of meroterpenoids. Among the meroditerpenoids isolated, stypodiol, isoepitaondiol, epitaondiol and sargaol exhibited gastroprotective activity on the HCl/Ethanol-induced gastric lesions model in mice. Regarding the mode of gastroprotective action, the activity of epitaondiol was reversed significantly when animals were pretreated with indomethacin, N-ethylmaleimide and N-nitro-l-arginine methyl ester (L-NAME) suggesting that prostaglandins, sulfhydryl groups and nitric oxide are involved in their mode of gastroprotective action. In the case of sargaol the gastroprotective activity was attenuated with indomethacin and N-ethylmaleimide, which suggests that prostaglandins and sulfhydryl groups are also involved in the mode of action using this model.}, keywords = {activity, algae, antiproliferative cytoprotection defense, epitaondiol, isoepitaondiol, meroditerpenoids, mucosal natural-products, zonale}, pubstate = {published}, tppubtype = {article} } Ten known meroterpenoids and the new meroterpenoid 7 were isolated from the Chilean seaweed Stypopodium flabelliforme as their acetylated derivatives. Furthermore, the known metabolite taondiol has been isolated for the first time from this species. The molecular structure of the new metabolite was determined by spectroscopic methods based on 1D- and 2D-NMR. Isolation of 7 represents a keywords step toward a better understanding of the biogenesis of this class of meroterpenoids. Among the meroditerpenoids isolated, stypodiol, isoepitaondiol, epitaondiol and sargaol exhibited gastroprotective activity on the HCl/Ethanol-induced gastric lesions model in mice. Regarding the mode of gastroprotective action, the activity of epitaondiol was reversed significantly when animals were pretreated with indomethacin, N-ethylmaleimide and N-nitro-l-arginine methyl ester (L-NAME) suggesting that prostaglandins, sulfhydryl groups and nitric oxide are involved in their mode of gastroprotective action. In the case of sargaol the gastroprotective activity was attenuated with indomethacin and N-ethylmaleimide, which suggests that prostaglandins and sulfhydryl groups are also involved in the mode of action using this model. |
2014 |
Sieveking, I; Thomas, P; Estevez, J C; Quinones, N; Cuellar, M A; Villena, J; Espinosa-Bustos, C; Fierro, A; Tapia, R A; Maya, J D; Lopez-Munoz, R; Cassels, B K; Estevez, R J; Salas, C O 2-Phenylaminonaphthoquinones and Related Compounds: Synthesis, Trypanocidal and Cytotoxic Activities Artículo de revista Bioorganic & Medicinal Chemistry, 22 (17), pp. 4609-4620, 2014, ISSN: 0968-0896. Resumen | Enlaces | BibTeX | Etiquetas: activity, antimalarial antineoplastic assay, benzocarbazolequinones, biological colorimetric cruzi, cytotoxicity, derivatives, electronic evaluation, general-route, properties, quinones, t. trypanosoma-cruzi @article{RN190, title = {2-Phenylaminonaphthoquinones and Related Compounds: Synthesis, Trypanocidal and Cytotoxic Activities}, author = { I. Sieveking and P. Thomas and J.C. Estevez and N. Quinones and M.A. Cuellar and J. Villena and C. Espinosa-Bustos and A. Fierro and R.A. Tapia and J.D. Maya and R. Lopez-Munoz and B.K. Cassels and R.J. Estevez and C.O. Salas}, url = {/brokenurl#<Go to ISI>://WOS:000341293300010}, doi = {10.1016/j.bmc.2014.07.030}, issn = {0968-0896}, year = {2014}, date = {2014-01-01}, journal = {Bioorganic & Medicinal Chemistry}, volume = {22}, number = {17}, pages = {4609-4620}, publisher = {2014 Elsevier Ltd.}, abstract = {A series of new 2-aminonaphthoquinones and related compounds were synthesized and evaluated in vitro as trypanocidal and cytotoxic agents. Some tested compounds inhibited epimastigote growth and trypomastigote viability. Several compounds showed similar or higher activity and selectivity as compared with current trypanocidal drug, nifurtimox. Compound 4l exhibit higher selectivity than nifurtimox against Trypanosoma cruzi in comparison with Vero cells. Some of the synthesized quinones were tested against cancer cells and normal fibroblasts, showing that certain chemical modifications on the naphthoquinone moiety induce and excellent increase the selectivity index of the cytotoxicity (4g and 10). The results presented here show that the anti-T. cruzi activity of 2-aminonaphthoquinones derivatives can be improved by the replacement of the benzene ring by a pyridine moiety. Interestingly, the presence of a chlorine atom at C-3 and a highly lipophilic alkyl group or aromatic ring are newly observed elements that should lead to the discovery of more selective cytotoxic and trypanocidal compounds.}, keywords = {activity, antimalarial antineoplastic assay, benzocarbazolequinones, biological colorimetric cruzi, cytotoxicity, derivatives, electronic evaluation, general-route, properties, quinones, t. trypanosoma-cruzi}, pubstate = {published}, tppubtype = {article} } A series of new 2-aminonaphthoquinones and related compounds were synthesized and evaluated in vitro as trypanocidal and cytotoxic agents. Some tested compounds inhibited epimastigote growth and trypomastigote viability. Several compounds showed similar or higher activity and selectivity as compared with current trypanocidal drug, nifurtimox. Compound 4l exhibit higher selectivity than nifurtimox against Trypanosoma cruzi in comparison with Vero cells. Some of the synthesized quinones were tested against cancer cells and normal fibroblasts, showing that certain chemical modifications on the naphthoquinone moiety induce and excellent increase the selectivity index of the cytotoxicity (4g and 10). The results presented here show that the anti-T. cruzi activity of 2-aminonaphthoquinones derivatives can be improved by the replacement of the benzene ring by a pyridine moiety. Interestingly, the presence of a chlorine atom at C-3 and a highly lipophilic alkyl group or aromatic ring are newly observed elements that should lead to the discovery of more selective cytotoxic and trypanocidal compounds. |
Brito, A; Areche, C; Sepulveda, B; Kennelly, E J; Simirgiotis, M J Anthocyanin Characterization, Total Phenolic Quantification and Antioxidant Features of Some Chilean Edible Berry Extracts Artículo de revista Molecules, 19 (8), pp. 10936-10955, 2014, ISSN: 1420-3049. Resumen | Enlaces | BibTeX | Etiquetas: activity, antioxidants, arrayan, berberis-microphylla berries, blueberry, calafate, capacity, chequen, chile, cultivars endemic fruits, hplc-ms, inhibitory liquid-chromatography, luma, mass-spectrometry, meli, murtilla, myrtaceae, oxidase poliphenolics, polyphenols, quantitation, southern vegetables @article{RN186, title = {Anthocyanin Characterization, Total Phenolic Quantification and Antioxidant Features of Some Chilean Edible Berry Extracts}, author = { A. Brito and C. Areche and B. Sepulveda and E.J. Kennelly and M.J. Simirgiotis}, url = {/brokenurl#<Go to ISI>://WOS:000341502600014}, doi = {10.3390/molecules190810936}, issn = {1420-3049}, year = {2014}, date = {2014-01-01}, journal = {Molecules}, volume = {19}, number = {8}, pages = {10936-10955}, abstract = {The anthocyanin composition and HPLC fingerprints of six small berries endemic of the VIII region of Chile were investigated using high resolution mass analysis for the first time (HR-ToF-ESI-MS). The antioxidant features of the six endemic species were compared, including a variety of blueberries which is one of the most commercially significant berry crops in Chile. The anthocyanin fingerprints obtained for the fruits were compared and correlated with the antioxidant features measured by the bleaching of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and total content of phenolics, flavonoids and anthocyanins measured by spectroscopic methods. Thirty one anthocyanins were identified, and the major ones were quantified by HPLC-DAD, mostly branched 3-O-glycosides of delphinidin, cyanidin, petunidin, peonidin and malvidin. Three phenolic acids (feruloylquinic acid, chlorogenic acid, and neochlorogenic acid) and five flavonols (hyperoside, isoquercitrin, quercetin, rutin, myricetin and isorhamnetin) were also identified. Calafate fruits showed the highest antioxidant activity (2.33 +/- 0.21 mu g/mL in the DPPH assay), followed by blueberry (3.32 +/- 0.18 mu g/mL), and arrayan (5.88 +/- 0.21), respectively.}, keywords = {activity, antioxidants, arrayan, berberis-microphylla berries, blueberry, calafate, capacity, chequen, chile, cultivars endemic fruits, hplc-ms, inhibitory liquid-chromatography, luma, mass-spectrometry, meli, murtilla, myrtaceae, oxidase poliphenolics, polyphenols, quantitation, southern vegetables}, pubstate = {published}, tppubtype = {article} } The anthocyanin composition and HPLC fingerprints of six small berries endemic of the VIII region of Chile were investigated using high resolution mass analysis for the first time (HR-ToF-ESI-MS). The antioxidant features of the six endemic species were compared, including a variety of blueberries which is one of the most commercially significant berry crops in Chile. The anthocyanin fingerprints obtained for the fruits were compared and correlated with the antioxidant features measured by the bleaching of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and total content of phenolics, flavonoids and anthocyanins measured by spectroscopic methods. Thirty one anthocyanins were identified, and the major ones were quantified by HPLC-DAD, mostly branched 3-O-glycosides of delphinidin, cyanidin, petunidin, peonidin and malvidin. Three phenolic acids (feruloylquinic acid, chlorogenic acid, and neochlorogenic acid) and five flavonols (hyperoside, isoquercitrin, quercetin, rutin, myricetin and isorhamnetin) were also identified. Calafate fruits showed the highest antioxidant activity (2.33 +/- 0.21 mu g/mL in the DPPH assay), followed by blueberry (3.32 +/- 0.18 mu g/mL), and arrayan (5.88 +/- 0.21), respectively. |
2013 |
Reinoso, R; Cajas-Madriaga, D; Martinez, M; Martin, San A; Perez, C; Fajardo, V; Becerra, J Biological Activity of Macromycetes Isolated from Chilean Subantarctic Ecosystems Artículo de revista Journal of the Chilean Chemical Society, 58 (4), pp. 2016-2019, 2013, ISSN: 0717-9707. Resumen | Enlaces | BibTeX | Etiquetas: activity, alkaloids and antibacterial, antifungal ecosystems, fungi, metabolites, secondary subantarctic @article{RN112, title = {Biological Activity of Macromycetes Isolated from Chilean Subantarctic Ecosystems}, author = { R. Reinoso and D. Cajas-Madriaga and M. Martinez and A. San Martin and C. Perez and V. Fajardo and J. Becerra}, url = {/brokenurl#<Go to ISI>://WOS:000331238800020}, doi = {10.4067/S0717-97072013000400024}, issn = {0717-9707}, year = {2013}, date = {2013-01-01}, journal = {Journal of the Chilean Chemical Society}, volume = {58}, number = {4}, pages = {2016-2019}, abstract = {Twenty six compounds were identified by GC-MS analysis from culture broth of six Macromycetes growing in subantarctic forests in southern Chile: Mycena hialinotricha, Collybia butyracea, Inocybe geophylla, Entoloma nubigenum, Stropharia semiglobata and Psathyrella sp. Antifungal and antibacterial activity were evaluated through agar diffusion test. This assay showed bioactivity against Penicillium notatum, Fusarium oxysporum, Rhyzoctonia solani, Ceratocistys pilifera, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, Escherichia faecalis and Staphilococcus aureus.}, keywords = {activity, alkaloids and antibacterial, antifungal ecosystems, fungi, metabolites, secondary subantarctic}, pubstate = {published}, tppubtype = {article} } Twenty six compounds were identified by GC-MS analysis from culture broth of six Macromycetes growing in subantarctic forests in southern Chile: Mycena hialinotricha, Collybia butyracea, Inocybe geophylla, Entoloma nubigenum, Stropharia semiglobata and Psathyrella sp. Antifungal and antibacterial activity were evaluated through agar diffusion test. This assay showed bioactivity against Penicillium notatum, Fusarium oxysporum, Rhyzoctonia solani, Ceratocistys pilifera, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, Escherichia faecalis and Staphilococcus aureus. |
Castro-Castillo, V; Suarez-Rozas, C; Castro-Loiza, N; Theoduloz, C; Cassels, B K Annulation of Substituted Anthracene-9,10-Diones Yields Promising Selectively Antiproliferative Compounds Artículo de revista European Journal of Medicinal Chemistry, 62 , pp. 688-692, 2013, ISSN: 0223-5234. Resumen | Enlaces | BibTeX | Etiquetas: activity, anthracene-9, anticancer antiproliferative binding crystal-structure, cytotoxic derivatives, oxoisoaporphines, synthetic @article{RN124, title = {Annulation of Substituted Anthracene-9,10-Diones Yields Promising Selectively Antiproliferative Compounds}, author = { V. Castro-Castillo and C. Suarez-Rozas and N. Castro-Loiza and C. Theoduloz and B.K. Cassels}, url = {/brokenurl#<Go to ISI>://WOS:000318577500069}, doi = {10.1016/j.ejmech.2013.01.049}, issn = {0223-5234}, year = {2013}, date = {2013-01-01}, journal = {European Journal of Medicinal Chemistry}, volume = {62}, pages = {688-692}, publisher = {2013 Elsevier Masson SAS.}, abstract = {Anthraquinone derivatives are well-known antiproliferative compounds, and some are currently used in cancer chemotherapy. Some families of annulated anthraquinone analogs have also been examined for antiproliferative activity, but in this regard almost nothing is known of 1-azabenzanthrones (7H-dibenzo [de,h]quinolin-7-ones). A series of 1-azabenzanthrone derivatives, their 2,3-dihydro analogs, and congruently substituted 9,10-anthracenediones were tested against normal human fibroblasts and four human cancer cell lines. Most of the heterocyclic compounds proved to be weakly to moderately antiproliferative with 1050 values extending down to 0.86 mu M, and exhibited up to 30-fold selectivity between cancer and normal cells. Both 1-azabenzanthrones and 1-aza-2,3-dihydrobenzanthrones were more potent than their anthraquinone counterparts, and almost without exception, the 2,3-dihydro compounds were more potent than the fully aromatic 1-azabenzanthrones.}, keywords = {activity, anthracene-9, anticancer antiproliferative binding crystal-structure, cytotoxic derivatives, oxoisoaporphines, synthetic}, pubstate = {published}, tppubtype = {article} } Anthraquinone derivatives are well-known antiproliferative compounds, and some are currently used in cancer chemotherapy. Some families of annulated anthraquinone analogs have also been examined for antiproliferative activity, but in this regard almost nothing is known of 1-azabenzanthrones (7H-dibenzo [de,h]quinolin-7-ones). A series of 1-azabenzanthrone derivatives, their 2,3-dihydro analogs, and congruently substituted 9,10-anthracenediones were tested against normal human fibroblasts and four human cancer cell lines. Most of the heterocyclic compounds proved to be weakly to moderately antiproliferative with 1050 values extending down to 0.86 mu M, and exhibited up to 30-fold selectivity between cancer and normal cells. Both 1-azabenzanthrones and 1-aza-2,3-dihydrobenzanthrones were more potent than their anthraquinone counterparts, and almost without exception, the 2,3-dihydro compounds were more potent than the fully aromatic 1-azabenzanthrones. |
Cheel, J; Tumova, L; Areche, C; Antwerpen, Van P; Neve, J; Zouaoui-Boudjeltia, K; Martin, A S; Vokral, I; Wsol, V; Neugebauerova, J Variations in the Chemical Profile and Biological Activities of Licorice (Glycyrrhiza Glabra L.), as Influenced by Harvest Times Artículo de revista Acta Physiologiae Plantarum, 35 (4), pp. 1337-1349, 2013, ISSN: 0137-5881. Resumen | Enlaces | BibTeX | Etiquetas: activity, antioxidant constituents, extracts, flavonoids, fruits harvest hplc, ldl licorice, liquid-chromatography, myeloperoxidase, oxidation, performance roots, seasonal-variations, times @article{RN115, title = {Variations in the Chemical Profile and Biological Activities of Licorice (Glycyrrhiza Glabra L.), as Influenced by Harvest Times}, author = { J. Cheel and L. Tumova and C. Areche and P. Van Antwerpen and J. Neve and K. Zouaoui-Boudjeltia and A.S. Martin and I. Vokral and V. Wsol and J. Neugebauerova}, url = {/brokenurl#<Go to ISI>://WOS:000316339400032}, doi = {10.1007/s11738-012-1174-9}, issn = {0137-5881}, year = {2013}, date = {2013-01-01}, journal = {Acta Physiologiae Plantarum}, volume = {35}, number = {4}, pages = {1337-1349}, abstract = {This study investigates the variations in the chemical profile, free radical scavenging, antioxidant and gastroprotective activities of licorice extracts (LE) from plants harvested during the months of February to November. Correlations between biological properties and the chemical composition of LE were also investigated. The results showed that the total contents of phenols, flavonoids and tannins in LE varied at different harvest times. Liquiritin and glycyrrhizin, the major components of LE, varied in the range of 28.65-62.80 and 41.84-114.33 mg g(-1), respectively. The relative proportion of glycyrrhizin derivative (3), glabridin (4), glabrene (5) and liquiritigenin derivative (6), varied in the range of 0.88-11.38 %, 1.86-10.03 %, 1.80-18.40 % and 5.53-16.31 %, respectively. These fluctuations correlated positively with changes in the antioxidant and free radical scavenging activities of licorice. In general, the samples from May and November showed the most favorable free radical scavenging and antioxidant effects, whereas the best gastroprotective effect was in May. Liquiritin and glycyrrhizin, the major constituents in the February and May LE, appeared to contribute to the superoxide radical scavenging and gastroprotective effects. Glabridin and glabrene, the compounds with the highest relative proportion in the November LE, accounted for the antioxidant and DPPH scavenging activities of licorice. It is concluded that the chemical profile of licorice quantitatively varied at different harvest times and these fluctuations determined changes in its bioactivities. These data could pave the way to optimize harvesting protocols for licorice in relation with its health-promoting properties.}, keywords = {activity, antioxidant constituents, extracts, flavonoids, fruits harvest hplc, ldl licorice, liquid-chromatography, myeloperoxidase, oxidation, performance roots, seasonal-variations, times}, pubstate = {published}, tppubtype = {article} } This study investigates the variations in the chemical profile, free radical scavenging, antioxidant and gastroprotective activities of licorice extracts (LE) from plants harvested during the months of February to November. Correlations between biological properties and the chemical composition of LE were also investigated. The results showed that the total contents of phenols, flavonoids and tannins in LE varied at different harvest times. Liquiritin and glycyrrhizin, the major components of LE, varied in the range of 28.65-62.80 and 41.84-114.33 mg g(-1), respectively. The relative proportion of glycyrrhizin derivative (3), glabridin (4), glabrene (5) and liquiritigenin derivative (6), varied in the range of 0.88-11.38 %, 1.86-10.03 %, 1.80-18.40 % and 5.53-16.31 %, respectively. These fluctuations correlated positively with changes in the antioxidant and free radical scavenging activities of licorice. In general, the samples from May and November showed the most favorable free radical scavenging and antioxidant effects, whereas the best gastroprotective effect was in May. Liquiritin and glycyrrhizin, the major constituents in the February and May LE, appeared to contribute to the superoxide radical scavenging and gastroprotective effects. Glabridin and glabrene, the compounds with the highest relative proportion in the November LE, accounted for the antioxidant and DPPH scavenging activities of licorice. It is concluded that the chemical profile of licorice quantitatively varied at different harvest times and these fluctuations determined changes in its bioactivities. These data could pave the way to optimize harvesting protocols for licorice in relation with its health-promoting properties. |
2012 |
Ponce, I; Silva, J F; Onate, R; Rezende, M C; Paez, M; Zagal, J H; Pavez, J; Mendizabal, F; Miranda-Rojas, S; Munoz-Castro, A; Arratia-Perez, R Journal of Physical Chemistry C, 116 (29), pp. 15329-15341, 2012, ISSN: 1932-7447. Resumen | Enlaces | BibTeX | Etiquetas: activity, alkylation, density-functional electrocatalytic electronic-structure, electroreductive hydrogen-peroxide, iron materials, metal-complexes molecular oxygen phthalocyanine, reduction, scanning-tunneling-microscopy, theory @article{RN83, title = {Enhancement of the Catalytic Activity of Fe Phthalocyanine for the Reduction of O-2 Anchored to Au(111) Via Conjugated Self-Assembled Mono Layers of Aromatic Thiols as Compared to Cu Phthalocyanine}, author = { I. Ponce and J.F. Silva and R. Onate and M.C. Rezende and M. Paez and J.H. Zagal and J. Pavez and F. Mendizabal and S. Miranda-Rojas and A. Munoz-Castro and R. Arratia-Perez}, url = {/brokenurl#<Go to ISI>://WOS:000306725200017}, doi = {10.1021/jp301093q}, issn = {1932-7447}, year = {2012}, date = {2012-01-01}, journal = {Journal of Physical Chemistry C}, volume = {116}, number = {29}, pages = {15329-15341}, abstract = {We have prepared self-assembled monolayers (SAMs) of 4-aminothiophenol (4-ATP) and 1-(4-mercaptophenyl)-2,6-diphenyl-4-(4-pyridyl)pyridinium tetrafluoroborate (MDPP) functionalized with iron phthalocyanine (Fe Pc) and copper phthalocyanine (Cu Pc) adsorbed on gold (111) electrodes. The catalytic activity of these SAMs/MPc was examined for the reduction of O-2 in aqueous solutions and compared to that of bare gold and with gold coated directly with preadsorbed MPc molecules. Scanning tunneling microscopy (STM) studies confirm the functionalization of the 4-ATP by MPc. STM images reveal that iron phthalocyanine molecules are chemically anchored to 4-aminothiophenol organic monolayers, probably having an "umbrella" type orientation with regards to the surface. The electrocatalytic studies carried out with Au/4-ATP/FePc and Au/MDPP/FePc electrodes show that the O-2 reduction takes place by the transfer of 4-electron to give water in contrast to a 2-electron transfer process observed for the bare gold. The modified electrode obtained by simple adsorption of FePc directly to the Au(111) surface still promotes the 4-electron reduction process, but it shows a lower activity than the electrodes involving SAMs with FePc molecules positioned at the outmost portion of the self-assembled monolayers. The activity of the electrodes increases as follow: Au < Au/FePc < Au/4-ATP/FePc < Au/MDPP/FePc with the highest activity when FePc molecules are more separated from the Au surface. In contrast, the less active CuPc shows almost the same activity in all three configurations. Theoretical calculations suggest the importance of the back-bonding into the adduct formation, showing the relevance of the supporting gold surface on the electron-transfer process mediated by anchoring ligands.}, keywords = {activity, alkylation, density-functional electrocatalytic electronic-structure, electroreductive hydrogen-peroxide, iron materials, metal-complexes molecular oxygen phthalocyanine, reduction, scanning-tunneling-microscopy, theory}, pubstate = {published}, tppubtype = {article} } We have prepared self-assembled monolayers (SAMs) of 4-aminothiophenol (4-ATP) and 1-(4-mercaptophenyl)-2,6-diphenyl-4-(4-pyridyl)pyridinium tetrafluoroborate (MDPP) functionalized with iron phthalocyanine (Fe Pc) and copper phthalocyanine (Cu Pc) adsorbed on gold (111) electrodes. The catalytic activity of these SAMs/MPc was examined for the reduction of O-2 in aqueous solutions and compared to that of bare gold and with gold coated directly with preadsorbed MPc molecules. Scanning tunneling microscopy (STM) studies confirm the functionalization of the 4-ATP by MPc. STM images reveal that iron phthalocyanine molecules are chemically anchored to 4-aminothiophenol organic monolayers, probably having an "umbrella" type orientation with regards to the surface. The electrocatalytic studies carried out with Au/4-ATP/FePc and Au/MDPP/FePc electrodes show that the O-2 reduction takes place by the transfer of 4-electron to give water in contrast to a 2-electron transfer process observed for the bare gold. The modified electrode obtained by simple adsorption of FePc directly to the Au(111) surface still promotes the 4-electron reduction process, but it shows a lower activity than the electrodes involving SAMs with FePc molecules positioned at the outmost portion of the self-assembled monolayers. The activity of the electrodes increases as follow: Au < Au/FePc < Au/4-ATP/FePc < Au/MDPP/FePc with the highest activity when FePc molecules are more separated from the Au surface. In contrast, the less active CuPc shows almost the same activity in all three configurations. Theoretical calculations suggest the importance of the back-bonding into the adduct formation, showing the relevance of the supporting gold surface on the electron-transfer process mediated by anchoring ligands. |
2011 |
Arrau, S; Delporte, C; Cartagena, C; Rodriguez-Diaz, M; González, P; Silva, X; Cassels, B K; Miranda, H F Antinociceptive Activity of Quillaja Saponaria Mol. Saponin Extract, Quillaic Acid and Derivatives in Mice Artículo de revista Journal of Ethnopharmacology, 133 (1), pp. 164-167, 2011, ISSN: 0378-8741. Resumen | Enlaces | BibTeX | Etiquetas: activity, analgesic assay, derivatives, drugs hot-plate models, pain, quillaic quillaja saponaria, tail-flick @article{RN4m, title = {Antinociceptive Activity of Quillaja Saponaria Mol. Saponin Extract, Quillaic Acid and Derivatives in Mice}, author = { S. Arrau and C. Delporte and C. Cartagena and M. Rodriguez-Diaz and P. Gonz\'{a}lez and X. Silva and B.K. Cassels and H.F. Miranda}, url = {/brokenurl#<Go to ISI>://WOS:000286854100023}, doi = {10.1016/j.jep.2010.09.016}, issn = {0378-8741}, year = {2011}, date = {2011-01-01}, journal = {Journal of Ethnopharmacology}, volume = {133}, number = {1}, pages = {164-167}, publisher = {2010 Elsevier Ireland Ltd.}, abstract = {Ethnopharmacological relevance: Quillaja saponaria bark contains a high percentage of triterpene saponins and has been used for centuries as a cleansing and analgesic agent in Chilean folk medicine., Aim of the study: The topical and systemic analgesic effects of a commercial partially purified saponin extract, 3 beta,16 alpha-dihydroxy-23-oxoolean-12-en-28-oic acid (quillaic acid), methyl 3 beta,16 alpha-dihydroxy-23-oxoolean-12-en-28-oate and methyl 4-nor-3,16-dioxoolean-12-en-28-oate., Materials and methods: The samples were assessed in mice using the topical tail-flick and i.p. hot-plate tests, respectively., Results: All the samples showed activity in both analgesic tests in a dose-dependent manner. The most active against tail flick test was commercial partially purified saponin extract (EC50 27.9 mg%, w/v) and more than the ibuprofen sodium. On hot-plate test, methyl 4-nor-3, 16-dioxoolean-12-en-28-oate was the most active (ED50 12.2 mg/kg) and more than the ibuprofen sodium., Conclusions: The results of the present study demonstrated that Quillaja saponaria saponins, quillaic acid, its methyl ester, and one of the oxidized derivatives of the latter, elicit dose-dependent antinociceptive effects in two murine thermal models.}, keywords = {activity, analgesic assay, derivatives, drugs hot-plate models, pain, quillaic quillaja saponaria, tail-flick}, pubstate = {published}, tppubtype = {article} } Ethnopharmacological relevance: Quillaja saponaria bark contains a high percentage of triterpene saponins and has been used for centuries as a cleansing and analgesic agent in Chilean folk medicine., Aim of the study: The topical and systemic analgesic effects of a commercial partially purified saponin extract, 3 beta,16 alpha-dihydroxy-23-oxoolean-12-en-28-oic acid (quillaic acid), methyl 3 beta,16 alpha-dihydroxy-23-oxoolean-12-en-28-oate and methyl 4-nor-3,16-dioxoolean-12-en-28-oate., Materials and methods: The samples were assessed in mice using the topical tail-flick and i.p. hot-plate tests, respectively., Results: All the samples showed activity in both analgesic tests in a dose-dependent manner. The most active against tail flick test was commercial partially purified saponin extract (EC50 27.9 mg%, w/v) and more than the ibuprofen sodium. On hot-plate test, methyl 4-nor-3, 16-dioxoolean-12-en-28-oate was the most active (ED50 12.2 mg/kg) and more than the ibuprofen sodium., Conclusions: The results of the present study demonstrated that Quillaja saponaria saponins, quillaic acid, its methyl ester, and one of the oxidized derivatives of the latter, elicit dose-dependent antinociceptive effects in two murine thermal models. |
Pereira, D M; Cheel, J; Areche, C; San-Martin, A; Rovirosa, J; Silva, L R; Valentao, P; Andrade, P B Anti-Proliferative Activity of Meroditerpenoids Isolated from the Brown Alga Stypopodium Flabelliforme against Several Cancer Cell Lines Artículo de revista Marine Drugs, 9 (5), pp. 852-862, 2011, ISSN: 1660-3397. Resumen | Enlaces | BibTeX | Etiquetas: activity, anti-proliferative, antimicrobial antimicrobial, assay epitaondiol, extracts, flabelliforme, marine-algae, meroditerpenoids, natural-products, stypopodium @article{RN3_28, title = {Anti-Proliferative Activity of Meroditerpenoids Isolated from the Brown Alga Stypopodium Flabelliforme against Several Cancer Cell Lines}, author = { D.M. Pereira and J. Cheel and C. Areche and A. San-Martin and J. Rovirosa and L.R. Silva and P. Valentao and P.B. Andrade}, url = {/brokenurl#<Go to ISI>://WOS:000292632500013}, doi = {10.3390/md9050852}, issn = {1660-3397}, year = {2011}, date = {2011-01-01}, journal = {Marine Drugs}, volume = {9}, number = {5}, pages = {852-862}, abstract = {The sea constitutes one of the most promising sources of novel compounds with potential application in human therapeutics. In particular, algae have proved to be an interesting source of new bioactive compounds. In this work, six meroditerpenoids (epitaondiol, epitaondiol diacetate, epitaondiol monoacetate, stypotriol triacetate, 14-ketostypodiol diacetate and stypodiol) isolated from the brown alga Stypopodium flabelliforme were tested for their cell proliferation inhibitory activity in five cell lines. Cell lines tested included human colon adenocarcinoma (Caco-2), human neuroblastoma (SH-SY5Y), rat basophilic leukemia (RBL-2H3), murine macrophages (RAW. 267) and Chinese hamster fibroblasts (V79). Antimicrobial activity of the compounds was also evaluated against Staphylococcus aureus, Salmonella typhimurium, Proteus mirabilis, Bacillus cereus, Enterococcus faecalis and Micrococcus luteus. Overall, the compounds showed good activity against all cell lines, with SH-SY5Y and RAW. 267 being the most susceptible. Antimicrobial capacity was observed for epitaondiol monoacetate, stypotriol triacetate and stypodiol, with the first being the most active. The results suggest that these molecules deserve further studies in order to evaluate their potential as therapeutic agents.}, keywords = {activity, anti-proliferative, antimicrobial antimicrobial, assay epitaondiol, extracts, flabelliforme, marine-algae, meroditerpenoids, natural-products, stypopodium}, pubstate = {published}, tppubtype = {article} } The sea constitutes one of the most promising sources of novel compounds with potential application in human therapeutics. In particular, algae have proved to be an interesting source of new bioactive compounds. In this work, six meroditerpenoids (epitaondiol, epitaondiol diacetate, epitaondiol monoacetate, stypotriol triacetate, 14-ketostypodiol diacetate and stypodiol) isolated from the brown alga Stypopodium flabelliforme were tested for their cell proliferation inhibitory activity in five cell lines. Cell lines tested included human colon adenocarcinoma (Caco-2), human neuroblastoma (SH-SY5Y), rat basophilic leukemia (RBL-2H3), murine macrophages (RAW. 267) and Chinese hamster fibroblasts (V79). Antimicrobial activity of the compounds was also evaluated against Staphylococcus aureus, Salmonella typhimurium, Proteus mirabilis, Bacillus cereus, Enterococcus faecalis and Micrococcus luteus. Overall, the compounds showed good activity against all cell lines, with SH-SY5Y and RAW. 267 being the most susceptible. Antimicrobial capacity was observed for epitaondiol monoacetate, stypotriol triacetate and stypodiol, with the first being the most active. The results suggest that these molecules deserve further studies in order to evaluate their potential as therapeutic agents. |
Cassels, B K; Asencio, M Anti-Hiv Activity of Natural Triterpenoids and Hemisynthetic Derivatives 2004-2009 Artículo de revista Phytochemistry Reviews, 10 (4), pp. 545-564, 2011, ISSN: 1568-7767. Resumen | Enlaces | BibTeX | Etiquetas: activity, kadsura-longipedunculata, modification, momordica-charantia, mushroom natural oleanane-type products, protease schisandra-lancifolia, skeleton, structural triterpenes, triterpenoids, unique @article{RN2_40, title = {Anti-Hiv Activity of Natural Triterpenoids and Hemisynthetic Derivatives 2004-2009}, author = { B.K. Cassels and M. Asencio}, url = {/brokenurl#<Go to ISI>://WOS:000297151800007}, doi = {10.1007/s11101-010-9172-2}, issn = {1568-7767}, year = {2011}, date = {2011-01-01}, journal = {Phytochemistry Reviews}, volume = {10}, number = {4}, pages = {545-564}, abstract = {The continued advance of HIV-AIDS makes the development of relatively inexpensive, freely accessible, and mechanistically more diverse antiviral therapies an urgent need. Natural products are, directly or indirectly, an important potential source of compounds meeting these conditions. A review of the recent literature indicates that some hemisynthetic triterpenoid derivatives, particularly belonging to the lupane, oleanane and ursane series, may be nearing a stage where they can be used to complement existing therapeutic approaches. On the other hand, although some natural derivatives of tetracyclic terpenoid families have revealed many novel structures and some promise as anti-HIV substances, their chemical modification to improve their potency and selectivity remains practically untouched. While ongoing work with the more 'classical' pentacyclic triterpenoids will continue to be a fertile field for HIV-AIDS drug discovery, the other structural groups offer unprecedented opportunities for the development of additional substances with useful properties and for the discovery of novel targets for antiviral therapy.}, keywords = {activity, kadsura-longipedunculata, modification, momordica-charantia, mushroom natural oleanane-type products, protease schisandra-lancifolia, skeleton, structural triterpenes, triterpenoids, unique}, pubstate = {published}, tppubtype = {article} } The continued advance of HIV-AIDS makes the development of relatively inexpensive, freely accessible, and mechanistically more diverse antiviral therapies an urgent need. Natural products are, directly or indirectly, an important potential source of compounds meeting these conditions. A review of the recent literature indicates that some hemisynthetic triterpenoid derivatives, particularly belonging to the lupane, oleanane and ursane series, may be nearing a stage where they can be used to complement existing therapeutic approaches. On the other hand, although some natural derivatives of tetracyclic terpenoid families have revealed many novel structures and some promise as anti-HIV substances, their chemical modification to improve their potency and selectivity remains practically untouched. While ongoing work with the more 'classical' pentacyclic triterpenoids will continue to be a fertile field for HIV-AIDS drug discovery, the other structural groups offer unprecedented opportunities for the development of additional substances with useful properties and for the discovery of novel targets for antiviral therapy. |
Areche, C; San-Martin, A; Rovirosa, J; Sepulveda, B Gastroprotective Activity of Epitaondiol and Sargaol Artículo de revista Natural Product Communications, 6 (8), pp. 1073-1074, 2011, ISSN: 1934-578x. Resumen | Enlaces | BibTeX | Etiquetas: activity, epitaondiol, flabelliforme gastroprotective sargaol, stypopodium @article{RN22f, title = {Gastroprotective Activity of Epitaondiol and Sargaol}, author = { C. Areche and A. San-Martin and J. Rovirosa and B. Sepulveda}, url = {/brokenurl#<Go to ISI>://WOS:000294035300005}, doi = {10.1177/1934578X1100600805}, issn = {1934-578x}, year = {2011}, date = {2011-01-01}, journal = {Natural Product Communications}, volume = {6}, number = {8}, pages = {1073-1074}, abstract = {The effects of epitaondiol (1) and sargaol (2), isolated from the brown alga Stypopodium flabelliforme on HCl/ethanol-induced gastric lesions in mice were evaluated and compared with that of lansoprazole. Epitaondiol and sargaol (6.25- 50 mg/kg) dose-dependently inhibited the appearance of gastric lesions in mice, displaying similar values to lansoprazole at 20 mg/kg. Both epitaondiol and sargaol showed gastroprotective activity with ED50 values of 40 mg/kg and 35 mg/kg, respectively. The results suggest that epitaondiol and sargaol protect the gastric mucosa in the HCl/EtOH model in mice.}, keywords = {activity, epitaondiol, flabelliforme gastroprotective sargaol, stypopodium}, pubstate = {published}, tppubtype = {article} } The effects of epitaondiol (1) and sargaol (2), isolated from the brown alga Stypopodium flabelliforme on HCl/ethanol-induced gastric lesions in mice were evaluated and compared with that of lansoprazole. Epitaondiol and sargaol (6.25- 50 mg/kg) dose-dependently inhibited the appearance of gastric lesions in mice, displaying similar values to lansoprazole at 20 mg/kg. Both epitaondiol and sargaol showed gastroprotective activity with ED50 values of 40 mg/kg and 35 mg/kg, respectively. The results suggest that epitaondiol and sargaol protect the gastric mucosa in the HCl/EtOH model in mice. |
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