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1.
Heliyon ; 10(4): e25542, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38380002

RESUMO

Eight Ribes magellanicum collections from three different places in southern Patagonia were compared for content of different groups of phenolics, antioxidant capacity and inhibition of enzymes related to metabolic syndrome (α-amylase, α-glucosidase and pancreatic lipase). The sample with the highest antioxidant capacity was assessed for glutathione (GSH) synthesis stimulation in human gastric adenocarcinoma (AGS) cells. The chemical profile was determined by high performance liquid chromatography with tandem mass spectrometry detection (HPLC-MS/MS) and the main phenolics were quantified. The samples from Navarino Island and Reserva Nacional Magallanes showed higher content of anthocyanins and caffeoylquinic acid, with better activity towards α-glucosidase and antioxidant capacity. A sample from Omora (Navarino Island), significantly increased intracellular GSH content in AGS cells. Some 70 compounds were identified in the fruit extracts by HPLC-MS/MS. The glucoside and rutinoside from delphinidin and cyanidin and 3-caffeoylquinic acid were the main compounds. Different chemical profiles were found according to the collection places.

2.
Braz. J. Pharm. Sci. (Online) ; 58: e191127, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1420451

RESUMO

Abstract The effects of Rheum ribes on lead acetate levels and hepatic biochemical factors due to lead acetate toxicity were investigated. Forty male Wistar rats were designated into four groups: Control; lead acetate (receiving in drinking water at 0.6 g/L, daily); hydroalcoholic extract groups (200 and 400 mg/kg doses, gavage, once daily). Treatments were conducted for 10 days. On the 11th day, blood samples were collected to measure lead acetate levels and biochemical factors. Liver tissue samples were examined for histopathological changes. Lead serum levels were increased in lead acetate-treated rats (p<0.001). Lead acetate treatment was associated with a significant increase in liver tissue damage (p<0.001), while R. ribes extract prevented liver tissue damage (p<0.05). The levels of alanine aminotransferase and aspartate aminotransferase were significantly lower in the groups lead acetate + extract (two doses) than in the lead acetate group (p<0.001 and P<0.01, respectively), but alkaline phosphatase level, prothrombin time, partial thromboplastin time and international normalized ratio were not different between the lead acetate + extract groups and the lead acetate group. The results showed the inhibitory role of R. ribes on lead-induced hepato-toxicity. The results make Rhubarb a good candidate to protect against the deleterious effect of chronic lead intoxication after complementary studies


Assuntos
Animais , Masculino , Ratos , Rheum/efeitos adversos , Extratos Vegetais/análise , Polygonaceae/classificação , Chumbo/toxicidade
3.
Food Res Int ; 129: 108848, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32036928

RESUMO

Chilean currants (Ribes magellanicum and Ribes punctatum) are wild polyphenol-rich berries with interesting bioactivities in several in vitro models. The aim of this study was to investigate the effects of the pre-digested PEE (polyphenol-enriched extract) in a simulated colon model. Fruits were extracted, submitted to simulated gastrointestinal digestion and further colonic fermentation with feces from healthy human donors. Samples were taken at 1, 4, 8 and 24 h of incubation, monitoring pH, ammonia, branched-chain fatty acids (BCFA), short-chain fatty acids (SCFA) and bacterial growth. FOS (fructooligosaccharides) and fecal slurry without treatments were positive and negative control, respectively. Both Ribes species reduced (p < 0.05) both BCFA and SCFA at 24 h. R. punctatum promoted the growth (p < 0.05) of beneficial bacteria such as Clostridium cluster XIVa, and Faecalibacterium prausnitzii; while a trend to increase Akkermansia muciniphila was observed. R. magellanicum increased (p < 0.05) Clostridium cluster XIVa population. Escherichia coli, Lactobacillus spp. and Bifidobacterium spp. remained unaffected. Our results suggest that polyphenols from R. punctatum and R. magellanicum may modulate both bacterial metabolism and some selected gut beneficial bacteria under simulated conditions. Therefore, Chilean currants might be useful as supplements to maintain a healthy colon; however, further in vivo studies are needed to confirm their effect and their mechanisms.


Assuntos
Bactérias/metabolismo , Fezes/microbiologia , Extratos Vegetais/farmacologia , Polifenóis/química , Ribes/química , Adulto , Amônia , Bactérias/classificação , Chile , DNA Bacteriano , Humanos , Concentração de Íons de Hidrogênio , Masculino , Extratos Vegetais/química
4.
Braz. J. Pharm. Sci. (Online) ; 55: e17832, 2019. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1055314

RESUMO

Rheumatoid arthritis is an autoimmune inflammatory disorder, despite the discovery of numerous drugs there is still need to introduce newer, safer and more effective sources of drugs such as medicinal herbs. Present research work was an attempt to appraise the antiarthritic potential of Ribes alpestre Decne in rheumatoid arthritis. In vitro inhibition of protein (bovine serum albumin and egg albumin) denaturation, Human red blood cell membrane stabilization assays along with formaldehyde induced arthritis in rats were commenced in this study. Findings of present investigation demonstrated significant and dose dependent antiarthritic effect of Ribes alpestre. Aqueous ethanolic extract, butanol and aqueous fraction illustrated 95%, 69.233% and 92.840% protection at 6400 ug/mL against bovine serum albumin denaturation respectively. Similarly, plant extract together with butanol and aqueous fractions showed 3653.47%, 1484.03% and 3563.19% inhibition of pathological alteration of egg albumin in that order. Moreover, hydroethanolic extract with butanol and aqueous fraction exhibited 91.29%, 65.73% and 89.62% stabilization against erythrocyte hemolysis at 6400 ug/mL correspondingly. Furthermore, hydroethanolic extract, butanol and aqueous fraction notably 73.49%, 66.42% and 68.87% decreased paw edema at highest dose (200 mg/kg). Similarly aqueous ethanolic extract, butanol and aqueous fraction illustrated 72.38%, 54.90% and 66.33% decrease in paw thickness at 200 mg/kg. Hence results suggested that Ribes alpestre possess antiarthritic potential thus supporting its use as natural remedy in rheumatic conditions.

5.
Food Chem ; 258: 144-155, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-29655716

RESUMO

The Chilean wild currants Ribes magellanicum and R. punctatum are a good source of polyphenols. Polyphenolic-enriched extracts (PEEs) from both species were submitted to in vitro colonic fermentation to assess the changes in phenolic composition, antioxidant capacity and inhibition of metabolic syndrome-associated enzymes. The phenolic profiles of the fermented samples showed significant changes after 24 h incubation. Nine metabolites, derived from the microbial fermentation, were tentatively identified, including dihydrocaffeic acid, dihydrocaffeoyl-, dihydroferuloylquinic acid, 1-(3,4-dihydroxyphenyl)-3-(2,4,6-trihydroxyphenyl)propan-2-ol (3,4-diHPP-2-ol), among others. The content of anthocyanins and hydroxycinnamic acids was most affected by simulated colonic conditions, with a loss of 71-92% and 90-100% after 24 h incubation, respectively. The highest antioxidant capacity values (ORAC) were reached after 8 h incubation. The inhibitory activity against the enzyme α-glucosidase was maintained after the fermentation process. Our results show that simulated colonic fermentation exerts significant changes on the polyphenolic composition of these berries, modifying their health-promoting properties.


Assuntos
Antioxidantes/química , Polifenóis/análise , Ribes/química , Adulto , Antocianinas/análise , Antocianinas/química , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Reatores Biológicos , Chile , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/análise , Ácidos Cumáricos/química , Fezes/microbiologia , Frutas/química , Frutas/metabolismo , Humanos , Masculino , Ribes/metabolismo , Espectrometria de Massas por Ionização por Electrospray , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
6.
Food Chem ; 237: 1073-1082, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28763953

RESUMO

The wild Chilean currants Ribes magellanicum and R. punctatum are a good source of polyphenolic compounds. The effect of simulated gastrointestinal digestion (GID) on phenolic content, composition and antioxidant capacity was determined. The inhibitory activity of the non-digested and digested samples towards metabolic syndrome-associated enzymes (α-amylase, α-glucosidase and lipase) was evaluated. The total phenolic (TP) and flavonoid contents (TF) decreased by about 50% at the end of the in vitro GID. Main anthocyanins and hydroxycinnamic acids were strongly affected by this process, with a loss of about 80%. A decrease in the antioxidant activity was observed throughout the digestion steps, which was correlated with the reduction in the TP and TF content. After the in vitro GID of the samples, only the inhibition of α-glucosidase was preserved. Our results show that the simulated GID modified the health-promoting properties of the studied currants.


Assuntos
Ribes , Antocianinas , Antioxidantes , Trato Gastrointestinal , Humanos , Extratos Vegetais , Polifenóis
7.
Food Sci Nutr ; 4(4): 595-610, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27386109

RESUMO

The Patagonian currant Ribes magellanicum is highly valued due to its pleasant flavor and sweet taste. The aim of this study was to characterize its constituents and to assess their antioxidant and cytoprotective properties. For the fruit phenolic-enriched extract (PEE), total phenolics (TP), total flavonoids (TF), and antioxidant activity (DPPH, Ferric reducing antioxidant power (FRAP), and Trolox equivalent antioxidant activity (TEAC)) were determined. Argentinean samples presented better activity in the DPPH and FRAP assays. Best cytoprotection against oxidative stress induced by H2O2 in AGS cells was found in one Argentinean sample at 500 µg mL(-1) (65.7%). HPLC MS/MS analysis allowed the tentative identification of 59 constituents, including eight anthocyanins, 11 conjugates of caffeic-, ferulic-, and coumaric acid, and 38 flavonoids, most of them quercetin and kaempferol derivatives. Argentinean samples showed a more complex pattern of anthocyanins, hydroxycinnamic acids (HCA), and flavonoids. Cyanidin rhamnoside hexoside and cyanidin hexoside were the main anthocyanins, accounting for 35 and 55% for the Argentinean and 60 and 27% for the ripe Chilean fruits. HCA content was about three times higher in Argentinean samples. The phenolic profiles of Chilean and Argentinean Ribes magellanicum show remarkable differences in chemical composition with higher HCA and flavonoid content in Argentinean samples.

8.
Univ. psychol ; 10(3): 949-962, sep. 2011.
Artigo em Espanhol | LILACS-Express | LILACS | ID: lil-650119

RESUMO

Como supuestos eventos solo accesibles a un observador, los llamados eventos privados plantean un reto importante a la Psicología Conductista. El problema de los eventos privados fue abordado desde las tres variantes históricas del conductismo: el conductismo metodológico, el conductismo radical y el interconductismo. El argumento básico de las dos últimas perspectivas, y que las diferencia de la primera, es que los eventos privados están comprendidos en el marco de una ciencia objetiva de la conducta. El análisis de estas distintas posturas permite comprobar el gradual avance de la teoría de la conducta, en el tratamiento de este tema, hacia una visión enteramente monista.


As supposed events being accessible to a unique observer, private events posit an interesting challenge to a behavioristic psychology. Three historical variants of behaviorism dealt with the problem of private events: methodological behaviorism, radical behaviorism and interbehaviorism. The basic argument of the two last views, and that distinguishes them from the former, is that private events are comprised into the scope of an objective science of behavior. The analysis of these accounts permits us to confirm a gradual advance in behavior theory, in dealing with this issue, toward a totally monistic view.

9.
Rev. peru. biol. (Impr.) ; 12(2)ago. 2005.
Artigo em Inglês | LILACS-Express | LILACS, LIPECS | ID: biblio-1522148

RESUMO

The taxonomy of the Ribes andicola group and Urtica is investigated for the relict forests in the Amotape-Huancabamba Zone and especially the relict forests of NW Peru. Three new species of Ribes are described, Ribes contumazensis as local endemic from Contumazá, R. colandina as widespread across the Andes from Lambayeque and La Libertad to Amazonas and R. sanchezii as endemic to forests overlooking the Marañon. Additionally, Ecuadoren R. austroecuadorense is recorded for the first time from Peru from forest relics in Huancabamba (Piura) and Chota (Cajamarca). Two new species of Urtica are described, U. urentivelutina as a local endemic on the slopes overlooking the Marañon near Chagual (La Libertad), and U. lalibertadensis which is widespread in La Libertad from Otuzco to Tayabamba. Urtica longispica is reported as new to the flora of Peru and U. macbridei is reported from northern Peru for the first time. Both Urtica and the Ribes andicola group can be considered as indicators of former forest cover, since they tenaciously persist after the felling of the forests. Their distribution indicates that a) some of the current forest fragments were once largely coherent forest belts (e.g., those of Santa Cruz and San Miguel) and b) some areas which have no coherent forest cover at present once had large and coherent montane forests (e.g., large parts of the Prov. Otuzco). Comparing the known distribution data for Urtica, the Ribes andicola group, the Passiflora lobbii group and Nasa (Loasaceae) it becomes evident, that a) the relict forests are still very poorly known, b) they are exceptionally rich in narrowly endemic taxa, some of which are here described and many of which undoubtedly remain to be discovered and c) they represent southernmost outposts for many Ecuadorean species and species groups.


Se investiga la taxonomía del grupo de Ribes andicola y Urtica para los bosques relictos presentes en la zona de Amotape-Huancabamba y especialmente aquellos de la vertiente NO del Perú. Se describen tres nuevas especies de Ribes: Ribes contumazensis como especie local endémica de Contumazá, R. colandina distribuida en los Andes desde Lambayeque y La Libertad hasta Amazonas y R. sanchezii como endémica a los bosques de altura del Marañón. Adicionalmente, la especie ecuatoriana R. austroecuadorense es registrada por primera vez para el Perú procedente de los bosques relictos de Huancabamba (Piura) y Chota (Cajamarca). Así mismo, se describen dos nuevas especies de Urtica: U. urentivelutina, endémica local a las laderas altas del Marañón cerca a Chagual (La Libertad), y U. lalibertadensis distribuida desde Otuzco hasta Tayabamba en el departamento de La Libertad. Urtica longispica es registrada como nueva especie para la flora del Peru y U. macbridei es registrada por primera vez para el norte del Perú. Urtica y el grupo Ribes andicola pueden ser considerados como indicadores de la cubierta de bosques anteriores, puesto que persisten después que los bosques han sido talados. Su distribución indica que a) alguno de los actuales fragmentos de bosque fueron alguna vez grandes bosques coherentes a modo de una faja contínua (como los de Santa Cruz y San Miguel) y b) algunas áreas que en el presente no tienen ninguna cubierta de bosques contínuos, en el pasado fueron grandes y coherentes bosques montanos (e.g., grandes partes de la Prov. Otuzco). Comparando los datos de distribución conocida para Urtica, el grupo de Ribes andicola, el grupo de Passiflora lobbii y Nasa (Loasaceae), es evidente, que a) los bosques relictos son aún muy pobremente estudiados, b) ellos son excepcionalmente ricos en taxa estrechamente endémicos, algunos de los cuales son aquí descritos y muchos de ellos indudablemente permanecen aún sin ser descubiertos y c) ellos representan los límites más sureños para muchas especies ecuatorianas y ciertos grupos de especies.

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