Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Plants (Basel) ; 11(20)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36297701

RESUMO

This study aimed to evaluate the potentials for skin-beneficial effects of the hydroethanolic extract of the aerial parts of ironwort (Sideritis raeseri Boiss. & Heldr. subsp. raeseri) and its fractions (petroleum ether, ethyl acetate, n-butanol and water). For these purposes, chemical analysis and in vitro antioxidant, anti-tyrosinase and antimicrobial assays, as well as determination of sun protection factor (SPF), were performed. The highest total phenolic content and quantity of individual flavonoids, chlorogenic acid and verbascoside were determined in the n-butanol fraction, which is in line with results obtained for antioxidant activity. The greatest antimicrobial activity against Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa, the most common causative agents of the skin infections in humans, was exhibited by the ethyl acetate fraction. The strongest anti-tyrosinase activity was shown by the hydroethanolic extract (52.64% of inhibition at 100 µg/mL). Almost all tested samples showed photoprotective activity with SPF higher than 6 obtained at a low concentration of 0.1 mg/mL, which was more than 15 for the butanol fraction. These findings revealed that the hydroethanolic extract of S. raeseri aerial parts could be a valuable ingredient in the formulation of cosmetic and medicinal products intended to overcome various skin disorders.

2.
Foods ; 10(9)2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34574078

RESUMO

This study aimed to establish a procedure for pomegranate peel (PP) valorization and attainment of stable extracts with preserved bioactive compounds. The technology applied was spray drying with carbohydrate-based (maltodextrin, MD) and protein-based (whey protein, WP) carrier materials in different concentrations (80, 100, and 120%). What was analyzed was the impact of the type and concentration of carrier material on the stability and quality of the final encapsulated powder. The best results were achieved when the PP extract was microencapsulated with the carbohydrate-based carrier (100%), where it had the highest encapsulation efficiency (EE) (88.63%), hygroscopicity (15.17%), and water solubility index (87.04%). The moisture content was in the range of 3.69-4.60% and 4.21-5.84% for MD and WP, respectively, indicating that both are suitable for long-term storage. It was observed that changes in carrier concentration significantly influenced most of the powders' physicochemical properties. Microencapsulation using MD yielded a higher content of punicalin, punicalagin, gallic, and ellagic acid than those with WP. Overall results demonstrated that carbohydrate-based microencapsulation can be utilized efficiently for the protection of powder stability and phytochemical characteristics.

3.
Plants (Basel) ; 10(8)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34451696

RESUMO

In vitro shoot culture of the endangered medicinal plant Gentianella lutescens was established from epicotyl explants cultured on MS basal medium with 0.2 mg L-1 6-benzylaminopurine (BA) and evaluated for xanthones content for the first time. Five shoot lines were obtained and no significant variations in multiplication rate, shoot elongation, and xanthones profile were found among them. The highest rooting rate (33.3%) was achieved by shoots treated for 2 days with 5 mg L-1 indole-3-butyric acid (IBA) followed by cultivation in liquid PGR-free ½ MS medium for 60 days. HPLC analysis revealed the lower content of xanthones-mangiferin, bellidifolin, demethylbellidifolin, demethylbellidifolin-8-O-glucoside and bellidifolin-8-O-glucoside-in in vitro cultured shoots compared to wild growing plants. The increasing concentration of sucrose, sorbitol and abiotic elicitors salicylic acid (SA), jasmonic acid (JA) and methyl jasmonate (MeJA) altered shoot growth and xanthone production. Sucrose and sorbitol applied at the highest concentration of 233.6 mM increased dry matter percentage, while SA at 100 µM promoted shoot growth 2-fold. The increased sucrose concentration enhanced accumulation of xanthones in shoot cultures 2-3-fold compared to the control shoots. Elicitors at 100-300 µM increased the accumulation of mangiferin, demethylbellidifolin-8-O-glucoside, and bellidifolin-8-O-glucoside almost equally, while MeJA at the highest concentration of 500 µM enhanced amount of aglycones demethylbellidifolin and bellidifolin 7-fold compared to the control. The obtained results facilitate conservation of G. lutescens and pave the way for further research on large-scale shoot propagation and production of pharmacologically active xanthones.

4.
Molecules ; 26(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203414

RESUMO

In this study we define the optimal conditions for ultrasound-assisted extraction of bioactive polyphenols from S. raeseri aerial parts using response surface methodology. The influence of ethanol concentration (10-90%), extraction temperature (20-80 °C), extraction time (10-60 min), and solid-to-solvent ratio (1:10-1:50) on total phenolic content as well as on content of individual flavonoids, and hypolaetin and isoscutellarein derivatives was studied. For the experimental design, a central composite design was chosen. In the obtained extracts, the following ranges of targeted compounds were detected: total phenol from 19.32 to 47.23 mg GAE/g dw, HYP from 1.05 to 11.46 mg/g dw, ISC 1 from 0.68 to 10.68 mg/g dw, and ISC 2 from 0.74 to 15.56 mg/g dw. The optimal extraction conditions were set as: ethanol concentration of 65%, extraction time of 50 min, extraction temperature of 63 °C, and solid-to-solvent ratio of 1:40. Contents of TP, HYP, ISC 1, and ISC 2 in optimal extracts were 47.11 mg GAE/g dw, 11.73 mg/g dw, 9.54 mg/g dw, and 15.40 mg/g dw, respectively. Experimentally set values were in good agreement with those predicted by the response surface methodology model, indicating suitability of the used model, as well as the success of response surface methodology in optimizing the conditions of the extraction.


Assuntos
Flavonoides , Micro-Ondas , Fenóis , Sideritis/química , Sonicação , Flavonoides/química , Flavonoides/isolamento & purificação , Fenóis/química , Fenóis/isolamento & purificação
5.
Plant Foods Hum Nutr ; 76(2): 203-209, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33825092

RESUMO

Human noroviruses (HuNoV) are the dominant cause of viral gastroenteritis in all age groups worldwide. In this study, we investigated the effects of pomegranate peel extract (PPE) on the reduction of HuNoV in different food models, on surfaces of fresh produce (green onion and cherry tomato), in low-fat milk, and simulated gastrointestinal fluids. The antiviral efficacy of PPE against HuNoV was evaluated by quantifying the number of residual virus genomes using a quantitative reverse transcription PCR (qRT-PCR) assay. Pomegranate peel, considered as a waste product of industrial processing, is known for beneficial health effects and broad antimicrobial activity due to the high content of phenolic compounds and tannins. PPE showed significant antiviral properties against HuNoV both in phosphate-buffered saline (PBS) and simulated gastric fluid. The reduction of HuNoV by pomegranate juice was lower than with PPE, which could be attributed to the lower content of antimicrobial compounds. A pretreatment of cherry tomato and green onion surfaces with PPE significantly reduced the amount of HuNoV particles that adhered to those surfaces during subsequent virus suspension treatment. A detrimental effect of PPE on HuNoV structure was confirmed by transmission electron microscopy. Our results indicate that PPE is a natural antiviral agent effective against food-borne noroviruses.


Assuntos
Norovirus , Punica granatum , Antivirais/farmacologia , Sucos de Frutas e Vegetais , Humanos , Extratos Vegetais/farmacologia
6.
Plant Foods Hum Nutr ; 75(4): 553-560, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32816146

RESUMO

Two environmentally friendly innovative extraction techniques - subcritical water (SWE) and microwave-assisted extraction (MAE) were applied for the extraction of phenolics from pomegranate peel. The impact of process conditions (SWE: temperature 100-220 °C, extraction time 5-30 min; MAE: solvent water and 50% ethanol, irradiation power 470 and 800 W) on the quality of extracts in terms of the content of total phenolics, total flavonoids, major phenolic constituents (gallic acid, ellagic acid, punicalin, punicalagin), as well as 5-hydroxymethylfurfural(HMF) amount was investigated. For SWE, temperature of 130 °C and 20 min extraction time were found optimal for obtaining high content of bioactive compounds and minimizing the yield of HMF. During MAE, phenolic compounds were effectively extracted by using lower microwave power and 50% ethanol. Comparing two techniques, MAE is more efficient than SWE for the extraction of phenolics from pomegranate peel while obtaining a HMF-free extracts.


Assuntos
Micro-Ondas , Água , Furaldeído/análogos & derivados , Extratos Vegetais , Punica granatum
7.
Plant Physiol Biochem ; 154: 735-744, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32763798

RESUMO

Shoot and root in vitro culture of endemic European species Gentiana clusii was established for the first time. The effects of different concentrations of benzyl adenine (BA), 6-phurphurylaminopurine (KIN), indole-3-butyric acid (IBA) and naphthalene acetic acid (NAA) on shoot propagation and rooting of G. clusii were investigated. The optimal in vitro conditions for shoot propagation and long-term maintenance were achieved using woody plant medium (WPM) supplemented with 0.5 mg l-1 KIN, and subsequent application of IBA at 0.5 mg l-1 significantly improved rooting of these shoots. Root culture was established from excised root tips cultured in ½ MS liquid media with increasing concentrations of IBA (0.1-1.0 mg l-1). A high root growth rate and considerable biomass yield were obtained by addition of 1.0 mg l-1 IBA. HPLC analysis revealed that in vitro culture considerably promoted the production of secondary metabolites in G. clusii. The selected protocol for shoot propagation (WPM + 0.5 mg l-1 KIN) increased the content of sweroside, gentiopicrin and norswertianin-1-O-primeveroside (N-1-P) for more than 2-fold compared with the wild plants. IBA promoted N-1-P and norswertianin production in root cultures; their contents were enhanced 6.4- and 18.6-fold, respectively, compared with the wild plants. The extract of these roots displayed the highest antioxidant capacity (IC50 = 66.57 µg ml-1). The established shoot and root propagation protocols facilitate in vitro conservation of G. clusii, and provides a promising tool for the large scale production of valuable secoiridoids and xanthones.


Assuntos
Gentiana/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Metabolismo Secundário , Técnicas de Cultura de Tecidos , Gentiana/crescimento & desenvolvimento , Meristema/crescimento & desenvolvimento , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento
8.
J Microencapsul ; 36(8): 693-703, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31549532

RESUMO

Aim: Microencapsulation of chokeberry extracts was performed in order to improve functionality, stability, and bioavailability of extracted polyphenols.Methods: Chokeberry fruits and juice by-product (waste) extracts were spray-dried by using two carriers, maltodextrin and skimmed milk. Morphological and physicochemical characteristics of the obtained powders were analysed. In vitro simulated digestion model was used as an indicator of polyphenolics bioavailability.Results: The moisture content varied between 3.39 and 4.61%, zeta potential had negative values (35-39 mV), maltodetrin powders were smaller (4.27-5.12 µm) compared to skimmed ones (8.50-11.01 µm). All microparticles exhibited high encapsulation efficiency of total polyphenols and anthocyanins (73-97% and 63-96%, respectively). For both extract types, maltodextrin powders released higher phenolics content compared to skimmed milk. During in vitro digestion, maltodextrin exhibited a higher protective effect on both active compounds.Conclusion: Taking into account the obtained results, chokeberry polyphenols stability might be improved using spray drying technique, and maltodextrin showed better properties.


Assuntos
Dessecação/métodos , Composição de Medicamentos/métodos , Leite/química , Photinia/química , Polifenóis/química , Polissacarídeos/química , Animais , Disponibilidade Biológica , Polifenóis/farmacocinética , Pós/análise , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Front Plant Sci ; 9: 1123, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30131818

RESUMO

Sandy everlasting [Helichrysum arenarium (L.) Moench] is herbaceous perennial plant belonging to Asteraceae family and it is native to Europe, Central Asia, and China. It belongs to the section HELICHRYSUM (Asteraceae family, genus Helichrysum) along with H. plicatum DC. Prodr., which very similar phenolic profile and H. italicum (Roth), which is widely used for essential oil extraction. Its flowers have a long tradition in European ethnomedicine as a cholagogue, choleretic, hepatoprotective, and detoxifying herbal drug. The flowers are rich in phenolic compounds including flavonoids, chalcones, phenolic acids, coumarins, and pyrones. Apart from polyphenols, other compounds such as sterols, lignans, and glycosides of aromatic compounds have been also isolated from H. arenarium. The majority of authors confirm that the most important group of compounds responsible for biological activities is flavonoids. Moreover, significant activities of naringenin, one of the main flavonoids of H. arenarium, were reported. On the other hand, there are no clinical data about testing the extracts or preparations based on H. arenarium. Although H. arenarium is well known in phytotherapy for its potential in the treatment of gallbladder disease and are classified as endangered species in a number of European countries, very few data about its cultivation are available in the literature.

10.
Food Chem ; 194: 135-42, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26471536

RESUMO

Traditional maceration method was used for the extraction of polyphenols from chokeberry (Aronia melanocarpa) dried fruit, and the effects of several extraction parameters on the total phenolics and anthocyanins contents were studied. Various solvents, particle size, solid-solvent ratio and extraction time have been investigated as independent variables in two level factorial design. Among examined variables, time was not statistically important factor for the extraction of polyphenols. The optimal extraction conditions were maceration of 0.75mm size berries by 50% ethanol, with solid-solvent ratio of 1:20, and predicted values were 27.7mgGAE/g for total phenolics and 0.27% for total anthocyanins. Under selected conditions, the experimental total phenolics were 27.8mgGAE/g, and total anthocyanins were 0.27%, which is in agreement with the predicted values. In addition, a complementary quantitative analysis of individual phenolic compounds was performed using HPLC method. The study indicated that maceration was effective and simple technique for the extraction of bioactive compounds from chokeberry fruit.


Assuntos
Antocianinas/química , Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Photinia/química , Polifenóis/análise , Fenóis/análise
11.
Food Chem ; 175: 516-22, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25577114

RESUMO

Chokeberry juice was subjected to in vitro gastric digestion in the presence of food matrix in order to determine the changes in polyphenol content and antioxidant activity. Addition of food matrix immediately decreased the total phenolic content, anthocyanin content, DPPH scavenging activity as well as total reducing power by 36%, 90%, 45% and 44%, respectively. After in vitro digestion, total phenolic content, anthocyanin content and reducing power are slightly elevated, but they are still lower than in initial non-digested juice. The effect of digested juice on Caco-2 cells proliferation was also studied, and the reduction of proliferative rate by approximately 25% was determined. Our results suggested that although a large proportion of chokeberry phenolics undergo transformation during digestion they are still potent as antioxidant and antiproliferative agents.


Assuntos
Antioxidantes/farmacologia , Frutas/química , Fenóis/análise , Photinia/química , Antioxidantes/análise , Antioxidantes/metabolismo , Bebidas , Trato Gastrointestinal/metabolismo , Humanos , Técnicas In Vitro , Modelos Biológicos , Fenóis/metabolismo , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia , Polifenóis/química , Polifenóis/metabolismo
12.
Food Chem Toxicol ; 55: 209-13, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23333716

RESUMO

This study was designed to evaluate the antibacterial activity of the Veronica montana L. water extract and its main phenolic compound, protocatechuic acid. The antibacterial activity was determined by microdilution assay against six strains of Gram-positive and Gram-negative bacteria. Listeria monocytogenes was the most sensitive of the tested bacterial species. Antibacterial preserving properties of protocatechuic acid were also evaluated after its incorporation in cream cheese, using L. monocytogenes as commonly cheese contaminant. The compound successfully inhibited L. monocytogenes development in cream cheese, at room temperature and in refrigerator (25°C and 4°C, respectively), after 3days of inoculation. Sensory evaluation was carried out in order to validate the mentioned food system. A possible mode of action of the tested compound towards bacterial cells was assessed and appears to be direct lysis of pathogenic cytoplasmic membrane. Prediction of pharmacokinetic properties was also performed using computational analyzes. The obtained results can serve as an important platform for the development of effective natural preservatives.


Assuntos
Antibacterianos/farmacologia , Microbiologia de Alimentos , Hidroxibenzoatos/farmacologia , Extratos Vegetais/farmacologia , Veronica/química , Cromatografia Líquida de Alta Pressão , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana
13.
J Med Food ; 16(1): 73-81, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23256443

RESUMO

Thirteen black currant varieties (Ribes nigrum L.) cultured in Serbia were characterized for their pomological properties and chemical composition (total phenolics, total anthocyanins, anthocyanin aglycones, sugars, and vitamin C). The average amount of vitamin C varied from 122.4 to 193.2 mg/100 g fresh weight (FW), while concentration of invert sugars ranged from 6.3% to 11.1%. The highest amounts of total phenolics and anthocyanins were detected in variety Ometa (278.9 mg of gallic acid equivalents per 100 g of FW [mg GAE/100 g FW] and 135.4 mg/100 g, respectively). Quantitative analyses of anthocyanin aglycones in berries were performed using high-performance liquid chromatography, and delphinidin was found to be dominant compound in 11 varieties. Total phenolics and anthocyanins contents decreased during the processing of berry fruits to juices, and the reduction of anthocyanins was more pronounced, 12%-80%. The radical scavenging activity of black currant juices was investigated by 1,1-diphenyl-2-picrylhydrazyl, and the IC(50) value ranged from 1.9 to 4.0 mg/mL. Our results also showed that freezing as a way of preservation and storage could save important phytochemicals and health benefits of berries and berry juices. The amount of total phenolics in berries increased during 1 year of storage by 46.09%-171.76% and in juices by even 107.58%, while the amount of total anthocyanins in berries and juices decrease by 5.63%-52.76% and 13.04%-36.82%, respectively.


Assuntos
Bebidas/análise , Preparações de Plantas/química , Ribes/química , Antocianinas/análise , Ácido Ascórbico/análise , Manipulação de Alimentos , Congelamento , Frutas/química , Fenóis
14.
Nat Prod Commun ; 7(11): 1487-90, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23285813

RESUMO

LC-ESI-MS and HPLC were used for the identification of the constituents from G. lutea leaves collected at different localities, as well as for quantification of the main compounds. Seven secoiridoids, five C-glucoflavones and three xanthones, were identified. Swertiamarin derivatives, namely eustomorusside (2), eustomoside (3) and septemfidoside (5), were detected in G. lutea for the first time. Concentrations of five constituents (swertiamarin, gentiopicrin, isovitexin, mangiferin and isogentisin) were determined. The relationship between concentrations of y-pyrones and altitude was observed with statistically significant correlation (r = 0.94). The extracts were also evaluated for their content of total phenolics, and antiradical and cytotoxic activities. The total phenolics content ranged from 7.7 to 12.7 mg GAE/g, and the IC50 values for DPPH radical scavenging activity varied between 0.45 to 2.02 mg/mL. The leaf extract exhibited moderate cytotoxic effects toward HeLa cells with an IC50 value of 41.1 microg/mL, while gentiopicrin, mangiferin and isogentisin exerted strong activity against HeLa cells, with IC50 values ranging from 5.7 to 8.8 microg/mL. The results confirm the traditional usage of G. lutea leaves and also suggest their possible utilization as hepatoprotective, hypoglycemic and anti-inflammatory agents.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Sequestradores de Radicais Livres/isolamento & purificação , Gentiana/química , Iridoides/isolamento & purificação , Xantonas/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Montenegro , Folhas de Planta/química
15.
Nat Prod Commun ; 6(6): 819-22, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21815418

RESUMO

Flowers of Helichrysum plicatum were extracted under different experimental conditions, and their antioxidant activity was determined by DPPH radical scavenging assay. Extracts obtained with higher concentration of ethyl acetate (90% or 100%) were found to contain the greatest amount of total phenolics (> 250 mg gallic acid equivalents/g of dried extract), and high correlation between total phenolic content and antiradical activity was observed (r = -0.79). Based on the total phenolic content and antiradical activity, some extracts were selected for investigation of cytotoxic activity toward PC3, HeLa and K562 human cancer cell lines in vitro. All tested extracts exhibited moderate activity against HeLa cells (41.9-42.1 microg/mL), whereas the extract obtained with 100% ethyl acetate was the most active against K562 and PC3 cell lines (25.9 and 39.2 microg/mL, respectively). Statistical analysis revealed significant correlation between total phenolic content and cytotoxic activity against PC3 and K562 cells. HPLC identification of phenolic compounds from the extracts indicated the presence of apigenin, naringenin and kaempferol as free aglycones, and glycosides of apigenin, naringenin, quercetin and kaempferol. Among aglycones, kaempferol displayed moderate cytostatic activity against all cell lines (24.8-64.7 microM).


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Flores/química , Helichrysum/química , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Linhagem Celular Tumoral , Humanos , Extratos Vegetais/química
16.
J Med Food ; 14(5): 495-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21480795

RESUMO

Sideritis raeseri spp. raeseri Boiss. & Heldr., known as "mountain tea," has been widely used in the Mediterranean region as a spice and in folk medicine as a very popular decoction because of its anti-inflammatory, carminative, analgesic, antitussive, stomachic, and antimicrobial properties. The study was aimed to investigate the effects of an ethanol extract of S. raeseri on intestinal activity. Air-dried and powdered aerial parts were extracted with 96% ethanol. The rat ileum preparations were incubated in Tyrode's solution gassed (95% O(2)/5% CO(2)) at 37°C. The ethanol extract of S. raeseri (0.03-0.3 mg/mL) relaxed spontaneous contractions in isolated rat ileum, similar to that produced by papaverine. The plant extract in a concentration-dependent manner (0.015-0.15 mg/mL) significantly inhibited the contractile response to acetylcholine (P<.01). Atropine inhibited the response to acetylcholine. A similar relaxation-inducing effect of the S. raeseri extract was observed on the precontracted ileum by histamine and barium chloride. Plant extract (0.03-0.3 mg/mL) significantly shifted the histamine concentration-response curve to the right and down (P<.01). The S. raeseri extract (0.03-0.3 mg/mL) significantly inhibited the contractions induced by barium chloride (P<.01). The results show that the ethanol extract of S. raeseri can produce inhibition of the the spontaneous rat ileum contractions and contractions induced by different spasmogens. These data indicate that S. raeseri acts as a spasmolytic on intestinal smooth muscle, which justifies its use in gastrointestinal disorders.


Assuntos
Íleo/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Parassimpatolíticos/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Sideritis/química , Acetilcolina/farmacologia , Animais , Atropina/farmacologia , Compostos de Bário/farmacologia , Cloretos/farmacologia , Etanol/metabolismo , Histamina/farmacologia , Técnicas In Vitro , Masculino , Músculo Liso/efeitos dos fármacos , Papaverina/farmacologia , Ratos , Ratos Wistar
17.
Plant Foods Hum Nutr ; 65(4): 326-32, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21046468

RESUMO

Eleven red currant varieties (Ribes rubrum L.) cultured in Serbia were evaluated for some of their biochemical properties such as total phenolics, anthocyanins, ascorbic acid, invert sugar, soluble solid content, and acidity. The average amount of ascorbic acid varied from 50.5-71.6 mg/100 g FW, while concentration of invert sugars ranged from 6.0%-9.0%. The highest amounts of total phenolics and anthocyanins were detected in variety Redpoll (153.4 mg GAE/100 g FW and 19.3 mg/100 g, respectively). Red currants were processed to juice, and the phenolic and anthocyanin contents changed as a result of processing. Berries and juices were long-term stored at -18 °C and changes in phytochemicals were monitored. In berries, storage caused the decrease of ascorbic acid content up to 49%, and a general reduction of total phenolics was also noticed. In juices, total phenolics content increased after one year of storage. In both berries and juices total anthocyanins increased during storage by up to 85% and 50%, respectively. This study demonstrates that certain varieties, namely Redpoll, Jonkheer and London Market are good source of phytochemicals, retaining the nutritional value during processing and storage.


Assuntos
Antocianinas/análise , Bebidas , Manipulação de Alimentos , Sequestradores de Radicais Livres/análise , Ribes/química , Ácido Ascórbico , Congelamento , Frutas/química , Frutas/metabolismo , Valor Nutritivo , Extratos Vegetais/análise , Sérvia
18.
Molecules ; 15(5): 3391-401, 2010 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-20657488

RESUMO

Helichrysum plicatum (Turkish Helichrysum) has been used in folk medicine for the treatment of gastric and hepatic disorders. The aim of the present study was to examine the relaxant activity of an extract of H. plicatum flowers on isolated rat ileum. Segments of ileum of rats were suspended in an organ bath. Cumulative concentrations of H. plicatum ethanol extract induced a relaxant effect on spontaneous rat ileum contractions. H. plicatum extract caused a mean contractile response of 81.68 +/- 6.17% (at a dose of 0.01 mg/mL) and 30.08 +/- 9.07% (at a dose of 1 mg/mL). A similar effect was observed with papaverine (0.01-3 microg/mL). H. plicatum extract (0.01-1 mg/mL) relaxed high K+ (80 mM) precontractions, an effect similar to that caused by papaverine (0.01-3 microg/mL). The plant extract (0.03-0.3 mg/mL) also induced a significant depression of the cumulative concentration response curve for acetylcholine (5-1500 nM) (p < 0.01). Atropine (140 nM) abolished the acetylcholine effect. The extract (0.03-0.3 mg/mL) reduced the histamine (1-300 nM) and BaCl2 (3-900 microM) induced contractions (p < 0.01). Our results showed the relaxant effect of the ethanol extract of Helichrysum plicatum flowers on the isolated rat intestine Extract of H. plicatum can inhibit the spontaneous ileum contractions and contractions induced by acetylcholine, histamine, barium and potassium ions.


Assuntos
Helichrysum/química , Íleo/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Extratos Vegetais/farmacologia , Acetilcolina/farmacologia , Animais , Etanol , Histamina/farmacologia , Íleo/fisiologia , Técnicas In Vitro , Extratos Vegetais/uso terapêutico , Ratos
19.
J Med Food ; 13(3): 700-4, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20438323

RESUMO

Antioxidant, cytotoxic, and antimicrobial activities of leaves, bark, and cone extracts of Alnus incana (L.) Moench ssp. incana and endemic species A. viridis (Chaix) DC ssp. viridis were evaluated. All extracts were found to be strong 1,1-diphenyl-2-picrylhydrazyl free radical scavengers, exhibiting 50% inhibitory concentration (IC(50)) values of 3.3-18.9 microg/mL, and also showed activity in inhibition of lipid peroxidation with IC(50) values ranging from 38.5 to 157.4 microg/mL. A. incana and A. viridis extracts exhibited significant cytotoxic effects toward HeLa cells, with IC(50) values ranging from 26.02 to 68.5 microg/mL. The most active extract of A. incana bark also contained great amounts of total phenolics (316.2 mg of gallic acid equivalents/g). In our experiment all extracts were virtually nontoxic on brine shrimps. Extracts were screened for activity against 15 microorganisms, and all extracts investigated showed antimicrobial activity. The most active were dry extracts of cones of A. incana and A. viridis with minimum inhibitory concentration values ranging from 0.117 to 0.129 mg/mL.


Assuntos
Alnus/química , Anti-Infecciosos/farmacologia , Antioxidantes/análise , Citotoxinas/farmacologia , Extratos Vegetais/farmacologia , Animais , Anti-Infecciosos/análise , Antioxidantes/farmacologia , Artemia/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Candida/efeitos dos fármacos , Citotoxinas/análise , Células HeLa , Humanos , Extratos Vegetais/análise
20.
Nat Prod Res ; 23(18): 1731-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19921591

RESUMO

Cytotoxicity and antioxidant properties of the methanol extracts of leaves and flowers of Cornus mas and Cotinus coggygria were studied, together with their chemical composition. Extracts of C. coggygria flowers and leaves showed better antioxidant activity in reaction with 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical as well as in inhibition of lipid peroxidation (LP) than C. mas extracts. Preliminary results showed that all extracts possessed potential cytotoxic activity towards HeLa and LS174 human cancer cell lines in vitro, with stronger inhibition against growth of HeLa cell growth than against LS174 cell growth. Cytotoxic activity of C. coggygria extracts showed good correlation with their antioxidative activity in vitro. In the brine shrimp lethality test, there were no significant changes in toxicity.


Assuntos
Anacardiaceae/química , Antioxidantes/química , Antioxidantes/farmacologia , Cornus/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Flores/química , Células HeLa , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Folhas de Planta/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...