Rafael Ricco - Academia.edu (original) (raw)
Papers by Rafael Ricco
Latin American Journal of Pharmacy, 2008
Acta Farmacéutica …, 1991
Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas
Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas
The genus Euphorbia in Patagonia is represented by species and varieties of the sections Anisophy... more The genus Euphorbia in Patagonia is represented by species and varieties of the sections Anisophyllum - Subsection Chamaesyceae and Tithymalus - Subsection Ipecacuanhae. Analyzed the aerial parts, in all the species and varieties quercetin was the main flavonol. Phytochemical significative differences could not be detected, turning out to be quercetin the only constant and stable compound. The antocianins and total phenols showed a changeable behavior probably due to the influence of environmental factors. The lack of activity for total tannins in the species of the Section Anisophyllum - Subsection Chamaesyceae, constitutes a useful character to separate them from the rest of the genus Euphorbia.
The “Argentine mistletoe”, Ligaria cuneifolia (R. et P.) Tiegh. (Loranthaceae), is a widespread h... more The “Argentine mistletoe”, Ligaria cuneifolia (R. et P.) Tiegh. (Loranthaceae), is a widespread hemiparasitic plant in the Argentine Republic. It is employed in folk medicine as a substitute of the “European mistletoe”, Viscum album L. (Viscaceae), because of its supposed action on decreasing high blood pressure. The anatomical studies on the “Argentine mistletoe” showed branched, crystalliferous stone cells as the main feature for this species, besides no other crystals were detected and the stem lacks cork. The study on polyphenols characterized the free or glycosilated quercetin as the only flavonol, together with leucocyanins and proanthocyanidins. Dihidroquercetin may follow two different metabolic pathways: one leading to quercetin by action of a flavonolsynthase, or another one which produces leucoanthocyanidins by a 3-hydroxyflavanone- 4-reductase. The joint of both types of compounds is characteristic for the “Argentine mistletoe” when compared to another Loranthaceae and V...
Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas
The aim of this paper was to study the presence of condensed tannins (proanthocyanidins) from Eph... more The aim of this paper was to study the presence of condensed tannins (proanthocyanidins) from Ephedra breana Phil.. Methanolic extracts obtained from young and woody stems were analyzed and compared. The only proanthocyanidin detected in the young stems was prodelphinidin. In the woody stems proapigeninidin was detected. Cuali-quantitative differences between young and woody stems were found, with higher contents of total phenols and proanthocyanidins in the young stems. These results are in agreement with the presence of higher molecular weight compounds (polymers) in the young stems, while in woody stems appear mostly lower molecular weight compounds. The higher concentration of tannins in young stems could be considered as a sort of defense mechanism against predators. On the other side, due to their chemical structure they could be a source of compounds that would act as antioxidant
Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas
Aqueous extracts from Prosopis chilensis (Mol.) Stuntz -Mimosaceae- fruits were analyzed and they... more Aqueous extracts from Prosopis chilensis (Mol.) Stuntz -Mimosaceae- fruits were analyzed and they displayed hemagglutinating activity, that was especifically inhibited with N-Acetyl-D-Galactosamine (GalNAc). A compound that bind GalNAc was identified by ion exchange and affinity chromatography techniques and SDS-PAGE. The aqueous extracts of the seeds did not displayed any hemagglutinating activity and the hemagglutininins identified in Prosopis chilensis would belong to the endocarp.
Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas
Phoradendron liga (Gill.) Eichl. is one of the most widely distributed Phoradendron species in Ar... more Phoradendron liga (Gill.) Eichl. is one of the most widely distributed Phoradendron species in Argentina. It is used in folk medicine as an hipotensive agent. The aim of this paper is to compare flavonoid profiles from plants growing in different geographic zones in order to establish if chemical races could occur. Standard procedures were used for flavonoid analysis. Flavon-C-glicosides and 3-desoxyproanthocyanidins were detected. Distribution of these compouds turned out to be different according to the related geographic zone.
Revista Brasileira de Farmacognosia, 2014
Revista Brasileira de Farmacognosia, 2013
Phytochemistry, 2001
Soybean cotyledons directly exposed to UV-C (190-280 nm) contained a colored pigment in those are... more Soybean cotyledons directly exposed to UV-C (190-280 nm) contained a colored pigment in those areas of the epidermis directly exposed to UV-C. Ethanolic extracts from UV-C irradiated cotyledons showed a significant peak at 532 nm at pH=10, but not seen at pH=6, successive changes in pH were accompanied by reversible changes in the spectra. The identity of the pigment isolated from soybean cotyledons was established as apigeninidin by comparing the features of standard of a apigeninidin (from sorghum) previously characterized by FAB-MS, UV, HPLC, 1H NMR, and IR spectroscopy. To characterize antioxidant activity of this compound, its ability to scavenge radical species in vitro was tested. In the concentration range tested (up to 200 microg ml (-1)), apigeninidin did not show any scavenger activity towards hydroxyl radical, quinones or NO. However, ascorbyl radical and lipid radicals were effectively quenched in a dose-dependent manner. Overall, UV-C radiation triggers molecular signals that lead in soybean cotyledons to the synthesis and accumulation of an antioxidant pigment, apigeninidin, that shows scavenger activity against ascorbyl and lipid radicals in in vitro studies.
Pharmaceutical Biology, 1998
Latin American Journal of Pharmacy, 2008
Acta Farmacéutica …, 1991
Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas
Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas
The genus Euphorbia in Patagonia is represented by species and varieties of the sections Anisophy... more The genus Euphorbia in Patagonia is represented by species and varieties of the sections Anisophyllum - Subsection Chamaesyceae and Tithymalus - Subsection Ipecacuanhae. Analyzed the aerial parts, in all the species and varieties quercetin was the main flavonol. Phytochemical significative differences could not be detected, turning out to be quercetin the only constant and stable compound. The antocianins and total phenols showed a changeable behavior probably due to the influence of environmental factors. The lack of activity for total tannins in the species of the Section Anisophyllum - Subsection Chamaesyceae, constitutes a useful character to separate them from the rest of the genus Euphorbia.
The “Argentine mistletoe”, Ligaria cuneifolia (R. et P.) Tiegh. (Loranthaceae), is a widespread h... more The “Argentine mistletoe”, Ligaria cuneifolia (R. et P.) Tiegh. (Loranthaceae), is a widespread hemiparasitic plant in the Argentine Republic. It is employed in folk medicine as a substitute of the “European mistletoe”, Viscum album L. (Viscaceae), because of its supposed action on decreasing high blood pressure. The anatomical studies on the “Argentine mistletoe” showed branched, crystalliferous stone cells as the main feature for this species, besides no other crystals were detected and the stem lacks cork. The study on polyphenols characterized the free or glycosilated quercetin as the only flavonol, together with leucocyanins and proanthocyanidins. Dihidroquercetin may follow two different metabolic pathways: one leading to quercetin by action of a flavonolsynthase, or another one which produces leucoanthocyanidins by a 3-hydroxyflavanone- 4-reductase. The joint of both types of compounds is characteristic for the “Argentine mistletoe” when compared to another Loranthaceae and V...
Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas
The aim of this paper was to study the presence of condensed tannins (proanthocyanidins) from Eph... more The aim of this paper was to study the presence of condensed tannins (proanthocyanidins) from Ephedra breana Phil.. Methanolic extracts obtained from young and woody stems were analyzed and compared. The only proanthocyanidin detected in the young stems was prodelphinidin. In the woody stems proapigeninidin was detected. Cuali-quantitative differences between young and woody stems were found, with higher contents of total phenols and proanthocyanidins in the young stems. These results are in agreement with the presence of higher molecular weight compounds (polymers) in the young stems, while in woody stems appear mostly lower molecular weight compounds. The higher concentration of tannins in young stems could be considered as a sort of defense mechanism against predators. On the other side, due to their chemical structure they could be a source of compounds that would act as antioxidant
Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas
Aqueous extracts from Prosopis chilensis (Mol.) Stuntz -Mimosaceae- fruits were analyzed and they... more Aqueous extracts from Prosopis chilensis (Mol.) Stuntz -Mimosaceae- fruits were analyzed and they displayed hemagglutinating activity, that was especifically inhibited with N-Acetyl-D-Galactosamine (GalNAc). A compound that bind GalNAc was identified by ion exchange and affinity chromatography techniques and SDS-PAGE. The aqueous extracts of the seeds did not displayed any hemagglutinating activity and the hemagglutininins identified in Prosopis chilensis would belong to the endocarp.
Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas
Phoradendron liga (Gill.) Eichl. is one of the most widely distributed Phoradendron species in Ar... more Phoradendron liga (Gill.) Eichl. is one of the most widely distributed Phoradendron species in Argentina. It is used in folk medicine as an hipotensive agent. The aim of this paper is to compare flavonoid profiles from plants growing in different geographic zones in order to establish if chemical races could occur. Standard procedures were used for flavonoid analysis. Flavon-C-glicosides and 3-desoxyproanthocyanidins were detected. Distribution of these compouds turned out to be different according to the related geographic zone.
Revista Brasileira de Farmacognosia, 2014
Revista Brasileira de Farmacognosia, 2013
Phytochemistry, 2001
Soybean cotyledons directly exposed to UV-C (190-280 nm) contained a colored pigment in those are... more Soybean cotyledons directly exposed to UV-C (190-280 nm) contained a colored pigment in those areas of the epidermis directly exposed to UV-C. Ethanolic extracts from UV-C irradiated cotyledons showed a significant peak at 532 nm at pH=10, but not seen at pH=6, successive changes in pH were accompanied by reversible changes in the spectra. The identity of the pigment isolated from soybean cotyledons was established as apigeninidin by comparing the features of standard of a apigeninidin (from sorghum) previously characterized by FAB-MS, UV, HPLC, 1H NMR, and IR spectroscopy. To characterize antioxidant activity of this compound, its ability to scavenge radical species in vitro was tested. In the concentration range tested (up to 200 microg ml (-1)), apigeninidin did not show any scavenger activity towards hydroxyl radical, quinones or NO. However, ascorbyl radical and lipid radicals were effectively quenched in a dose-dependent manner. Overall, UV-C radiation triggers molecular signals that lead in soybean cotyledons to the synthesis and accumulation of an antioxidant pigment, apigeninidin, that shows scavenger activity against ascorbyl and lipid radicals in in vitro studies.
Pharmaceutical Biology, 1998