170 research outputs found
Direct identification of phenolic constituents in Boldo Folium (Peumus boldus Mol.) infusions by high-performance liquid chromatography with diode array detection and electrospray ionization tandem mass spectrometry
Get PDFA very simple and direct method was developed for the qualitative analysis of polyphenols in boldo (Peumus boldus Mol., Monimiaceae) leaves infusions by high-performance liquid chromatography with diode array detection (HPLC-DAD) and electrospray ionization tandem mass spectrometry (HPLC-MSn). The phenolic constituents identified in infusions of the crude drug Boldo Folium were mainly proanthocyanidins and flavonol glycosides. In the infusions, 41 compounds were detected in male and 43 compounds in female leaf samples, respectively. Nine quercetin glycosides, eight kaempferol derivatives, nine isorhamnetin glycosides, three phenolic acids, one caffeoylquinic acid glycoside and twenty one proanthocyanidins were identified by HPLC-DAD and ESI-MS for the first time in the crude drug. Isorhamnetin glucosyl-di-rhamnoside was the most abundant flavonol glycoside in the male boldo sample, whereas isorhamnetin di-glucosyl-di-rhamnoside was the main phenolic compound in female boldo leaves infusion. The results suggest that the medicinal properties reported for this popular infusion should be attributed not only to the presence of catechin and boldine but also to several phenolic compounds with known antioxidant activity. The HPLC fingerprint obtained can be useful in the authentication of the crude drug Boldo Folium as well as for qualitative analysis and differentiation of plant populations in the tree distribution range.Fil: Simirgiotis, Mario Juan. Universidad de Talca; Chile. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Schmeda Hirschmann, Guillermo. Universidad de Talca; Chil
Determination of phenolic composition and antioxidant activity in fruits, rhizomes and leaves of the white strawberry (Fragaria chiloensis spp. chiloensis form chiloensis) using HPLC-DAD-ESI-MS and free radical quenching techniques
Get PDFA comparative analysis of methanol extracts from fruits, rhizomes and leaves of the Chilean white strawberry (Fragaria chiloensis spp. chiloensis var chiloensis) was performed by means of reversed phase high-performance liquid chromatography coupled to diode array detection and electrospray ionization mass spectrometry (HPLC-DAD and HPLC-ESI-MS). The total phenolic, total flavonoid and total anthocyanin content of the extracts was measured and compared. For the first time, some 18 phenolic compounds were tentatively identified in rhizomes and 18 in leaves of the Chilean strawberry. The products were mainly procyanidins, ellagitannins, ellagic acid and flavonol derivatives. The different extracts of the native strawberry presented antioxidant activity, which was close to that exhibited by the white fruits. The rhizomes and leaves proved to be a good source of phenolic antioxidants. The obtained information can be used to characterize the local cultivars by metabolite profiling and provide a reference HPLC fingerprint for future comparison of chemical changes associated to the plant response towards environmental factors and pathogens.Fil: Simirgiotis, Mario Juan. Universidad de Talca; Chile. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: Schmeda Hirschmann, Guillermo. Universidad de Talca; Chil
Chemistry of the Chilean Strawberry (Fragaria chiloensis spp. chiloensis)
Get PDFThe Chilean strawberry (Fragaria chiloensis spp. chiloensis) is one of the progenitors of the cultivated strawberry, Fragaria × ananassa.Recent studies have started to disclose the chemical composition of the native fruit, the secondary metabolite occurrence and distributionin different plant parts as well as the biological activity of the main fruit constituents. This article revises the chemistry of the Chileanstrawberry and compares some of the most characteristic constituents with that of the highly cultivated and worldwide known F. ×ananassa. The main phenolic in the white strawberry are ellagic acid or hexahydroxydiphenolic acid-based hydrolysable tannins and procyanidinsas well as flavonoid glycosides from quercetin and kaempferol. The general trend in the plant is the accumulation of condensedtannins of increasing molecular weight in the rhizomes while the leaf contains mainly hydrolysable tannins and flavonoids.Fil: Schmeda Hirschmann, Guillermo. Universidad de Talca; ChileFil: Simirgiotis, Mario Juan. Universidad de Antofagasta; Chile. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: Cheel, José. CPN Ltd.; República Checa. Univerzita Karlova; República Chec
New Dammarane Triterpenes from the aerial parts of Ibicella lutea grown in Argentina
Get PDFTwo new dammarane triterpenes have been isolated from the aerial parts of Ibicella lutea, 3-acetyl-24- epi-polacandrin (1) and 1,3-diacetyl-24-epi-polacandrin (2), and were obtained along with the known compounds 20S*,24S*-epoxy-3â,12â,25-trihydroxydammarane (3) and apigenin. The structures of compounds 1 and 2 were deduced by spectroscopic studies and by chemical transformations leading to the preparation of derivatives 4-11. The structure and relative stereochemistry of 1 were verified by single-crystal X-ray analysis. The natural compounds and selected semisynthetic derivatives were evaluated against several tumor cells.Fil: Simirgiotis, Mario Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Jiménez, Carlos. Universidad da Coruña; EspañaFil: Rodríguez, Jaime. Universidad da Coruña; EspañaFil: Giordano, Oscar Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Tonn, Carlos Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; Argentin
Antioxidant Capacity and HPLC-DAD-MS Profiling of Chilean Peumo (Cryptocarya alba) Fruits and Comparison with German Peumo (Crataegus monogyna) from Southern Chile
No full textLiquid chromatography (LC) coupled with UV detection and electrospray ionization (ESI) tandem mass spectrometry (MS/MS) was used for the generation of chemical fingerprints and the identification of phenolic compounds in peumo fruits and aerial parts from southern Chile. Thirty three compounds (19 of these detected in C. alba and 23 in C. monogyna) were identified, mainly flavonoid glycosides, phenolic acids, anthocyanins and flavonoid aglycons. Total phenolic content and total flavonoid content was measured for both species, and were higher in the extracts from C. monogyna fruits and aerial parts than extracts from C. alba. The fruits of Cryptocarya alba (Chilean peumo) presented high antioxidant capacity (9.12 ± 0.01 mg/mL in the DPPH assay), but was three times lower to that of Crataegus monogyna (German peumo) (3.61 ± 0.01 mg/mL in the DPPH assay)
Ultra-High-Resolution Liquid Chromatography Coupled with Electrospray Ionization Quadrupole Time-of-Flight Mass Spectrometry Analysis of Tessaria absinthioides (Hook. & Arn.) DC. (Asteraceae) and Antioxidant and Hypocholesterolemic Properties
Get PDFRecently, we reported the chemical profile and the hypocholesterolemic effects of a decoction of Tessaria absinthioides (Hook. & Arn.) DC. (Asteraceae). In this study, we evaluated a methanolic extract (METa) instead. Metabolite profiling was conducted using ultra-high-resolution liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (UHPLC-ESI-QTOF-MS), identifying thirty compounds, including flavonoids, phenolic acids, fatty acids, and phorbolesters. Antioxidant properties were assessed through 2,2-diphenyl-1-picrylhydrazyl (DPPH), Trolox equivalent antioxidant activity (TEAC), ferric-reducing antioxidant power (FRAP), and inhibition of lipid peroxidation in erythrocytes (ILP) assays, exhibiting robust antioxidant activity. The in vivo impact of METa on serum lipid parameters and liver X receptors (LXRs) was evaluated in a hypercholesterolemic animal model. After 14 days on a high-fat diet, male rats received either a vehicle (V) or METa100, METa200 or METa500 (100; 200 and 500 mg METa/kg animal, respectively) for an additional two weeks. METa500 reduced total cholesterol levels (17.62%; p < 0.05) and all doses increased high-density lipoprotein cholesterol levels (METa100: 86.27%; METa200: 48.37%, and METa500: 29.42%; p < 0.0001). However, METa did not alter LXRs expression. The observed antioxidant and hypocholesterolemic properties of METa may be linked to the presence of six di-caffeoylquinic acids. These findings underscore T. absinthioides as a potential candidate for the treatment of metabolic disease.Fil: Rey, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Kruse, Maria Sol. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Gómez, Jessica. Universidad Nacional de San Juan. Facultad de Filosofía, Humanidades y Artes. Instituto de Ciencias Básicas; ArgentinaFil: Simirgiotis, Mario J.. Universidad Austral de Chile; ChileFil: Tapia, Alejandro. Universidad Nacional de San Juan. Facultad de Filosofía, Humanidades y Artes. Instituto de Ciencias Básicas; ArgentinaFil: Coirini, Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentin
Antioxidant and Antidiabetic Potential of the Antarctic Lichen Gondwania regalis Ethanolic Extract: Metabolomic Profile and In Vitro and In Silico Evaluation
No full textLichens are an important source of diverse and unique secondary metabolites with recognized biological activities through experimental and computational procedures. The objective of this study is to investigate the metabolomic profile of the ethanolic extract of the Antarctic lichen Gondwania regalis and evaluate its antioxidant and antidiabetic activities with in vitro, in silico, and molecular dynamics simulations. Twenty-one compounds were tentatively identified for the first time using UHPLC/ESI/QToF/MS in negative mode. For antioxidant activity, the DPPH assay showed an IC50 value of 2246.149 µg/mL; the total phenolic content was 31.9 mg GAE/g, the ORAC assay was 13.463 µmol Trolox/g, and the FRAP assay revealed 6.802 µmol Trolox/g. Regarding antidiabetic activity, enzyme inhibition yielded IC50 values of 326.4513 µg/mL for pancreatic lipase, 19.49 µg/mL for α-glucosidase, and 585.216 µg/mL for α-amylase. Molecular docking identified sekikaic acid as the most promising compound, with strong binding affinities to catalytic sites, while molecular dynamics confirmed its stability and interactions. Toxicological and pharmacokinetic analyses supported its drug-like potential without significant risks. These findings suggest that the ethanolic extract of Gondwania regalis is a promising source of bioactive compounds for developing natural antioxidant and antidiabetic therapies
Dammarane triterpenes targeting α-synuclein: biological activity and evaluation of binding sites by molecular docking
Get PDFParkinson’s disease (PD) is a neurodegenerative disorder that affects adult people whose treatment is palliative.
Thus, we decided to test three dammarane triterpenes 1, 1a, 1b, and we determined that 1 and
1a inhibit b-aggregation through thioflavine T rather than 1b. Since compound 1 was most active, we
determined the interaction between a-synuclein and 1 at 50 mM (Kd) through microscale thermophoresis.
Also, we observed differences in height and diameter of aggregates, and a-synuclein remains unfolded in
the presence of 1. Also, aggregates treated with 1 do not provoke neurites’ retraction in N2a cells previously
induced by retinoic acid. Finally, we studied the potential sites of interaction between 1 with a-synuclein
fibrils using molecular modelling. Docking experiments suggest that 1 preferably interact with the
site 2 of a-synuclein through hydrogen bonds with residues Y39 and T44.Instituto Antartico Chileno (INACH) RT_18-19
Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT)
CONICYT FONDECYT 1170718
Mario Simirgiotis FONDECYT Regular 1180059
Francisco Melo FONDECYT Regular 1201013
Fondequip EQM130149
USA2055-042031MH_POSTDOCVersión publicada - versión final del edito
An ent-kaurene derivative from aerial parts of baccharis rufescens
No full textFrom aerial parts of Baccharis refescens Sprengel (Asteraceae: Astereae), the diterpene ent-3a,19-disuccinyloxy-kaur-16-ene (1) was isolated along with the triterpene oleanolic acid (4) and the flavonoids cirsimaritin (5,4'-dihidroxy-6,7-dimethoxyflavone) (5), and cirsiliol (5, 3',4'-trihidroxy-6,7-dimethoxyflavone) (6). Biological assays aimed to evaluate the incidence of compound 1 and its methyl ester derivative (2) on the food comsuption of adults of Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), showed that compound 2 exhibited a significant antifeedant activity.De partes aéreas de Baccharis rufescens Sprengel (Asteraceae: Astereae) fue aislado al diterpeno ent-3a,19-disucciniloxi-kaur-16-eno (1) además el triterpeno ácido oleanólico (4) y los flavonoides cirsimaritina (5,4'-dihidroxi-6,7-dimetoxiflavona) (5) y cirsiliol (5, 3',4'-trihidroxi-6, 7-dimetoxiflavona) (6). Ensayos biológicos dirigidos a evaluar la incidencia en el comportamiento alimentario del compuesto 1 y su metil éster (2) sobre adultos de Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), permitieron asignar al compuesto 2 una significativa actividad antialimentaria.Fil: Simirgiotis, Mario Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Garcia, Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Sosa, Marta Edit. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Giordano, Oscar Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Tonn, Carlos Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; Argentin
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