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| Registros recuperados: 54 | |
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| Ballus,Cristiano Augusto; Meinhart,Adriana Dillenburg; Bizzotto,Carolina Schaper; Teixeira Filho,José; Godoy,Helena Teixeira. |
| Energy drinks are becoming popular in Brazil and in the world due to their stimulant properties. Caffeine is present in energy drinks with the aim of stimulating the central nervous system and intensifying brain activity. On the other hand, the ingestion of high doses of caffeine can cause undesirable symptoms such as anxiety and tachycardia. Therefore, it is necessary to monitor the caffeine content added to energy drinks to guarantee that the levels in the final product are in accordance with the labeling and within the legislation limits. The goal of this work was to validate a fast, efficient, and low-cost method for the determination of caffeine in energy drinks by micellar electrokinetic chromatography (MEKC). A total of seven brands were analyzed,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Caffeine; Energy drinks; Micellar electrokinetic chromatography. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612012000200029 |
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| Malta, Marcelo Ribeiro; EPAMIG; Chagas, Sílvio Júlio de Rezende; EPAMIG. |
| O presente trabalho teve como objetivo avaliar os teores de trigonelina, ácidos clorogênicos (5-ACQ) e cafeína em grãos de diferentes cultivares de cafeeiro (Coffea arabica L.). As cultivares avaliadas foram coletadas na Fazenda Experimental da Epamig em Lavras, Estado de Minas Gerais, no ano agrícola de 2005/2006. O delineamento experimental utilizado foi um inteiramente casualizado constando de oito cultivares de café com três repetições. Foram avaliadas as cultivares: Oeiras MG 6851, Acaiá Cerrado MG 1474, Catuaí Vermelho IAC 99, Rubi MG 1192, Topázio MG 1190, Mundo Novo IAC 379/19, Catucaí Amarelo 2 SL e Catuaí Amarelo IAC 62. Após a colheita dos cafés por derriça manual no pano, estes foram lavados e submetidos ao processo de descascamento e... |
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Palavras-chave: 5.01.03.04-0 Produção de Mudas Coffea arabic; Melhoramento; Composição química; Ácido clorogênico; Cafeína; Trigonelina. Coffea Arabica; Breeding; Chemical composition; Chlorogenic acids; Caffeine; Trigonelline. |
| Ano: 2009 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/6629 |
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| Human skinned muscle fibers were used to investigate the effects of bovine serum albumin (BSA) on the tension/pCa relationship and on the functional properties of the Ca2+-release channel of the sarcoplasmic reticulum (SR). In both fast- and slow-type fibers, identified by their tension response to pSr 5.0, BSA (0.7-15 µM) had no effect on the Ca2+ affinity of the contractile proteins and elicited no tension per se in Ca2+-loaded fibers. In contrast, BSA (>1.0 µM) potentiated the caffeine-induced tension in Ca2+-loaded fibers, this effect being more intense in slow-type fibers. Thus, BSA reduced the threshold caffeine concentration required for eliciting detectable tension, and increased the amplitude, the rate of rise and the area under the curve... |
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Palavras-chave: Calcium-release channel; Sarcoplasmic reticulum; Human muscle fiber; Bovine serum albumin; Caffeine. |
| Ano: 1997 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000500017 |
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| Tagliari,Cristiane Vanessa; Sanson,Raquel K.; Zanette,André; Franco,Telma Teixeira; Soccol,Carlos Ricardo. |
| Various microorganisms including bacteria, yeast and fungi can degrade caffeine. There are few publications about caffeine degradation pathway in filamentous fungi, mainly by solid-state fermentation (SSF). Studies were carried out on degradation of caffeine and their metabolites by filamentous fungi in SSF using coffee husk as substrate. The purpose of this work was to investigate the caffeine degradation pathway by Rhizopus delemar in packed bed column fermenter and to compare this degradation metabolism with glass flasks fermentation. The methylxanthines were quantified by HPLC analysis. The experiments were realized with the optimized conditions in previous experiments: pH 6.5, 28ºC, inoculation rate 10(6) spores/g substrate, aeration rate 60 mL/min... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Decaffeination; Fermentation; Caffeine; Theophylline; Bioreactor; Filamentous fungi. |
| Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822003000500035 |
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| Sartor,Rosana Mary; Mazzafera,Paulo. |
| The low caffeine content in leaves of C. dewevrei (~ 0.5 mg/g) is due to a low biosynthesis associated with a fast degradation. On the other hand, high biosynthesis and low degradation confer a higher content (~ 8 mg/g) in leaves of C. arabica. In this work it was observed that cell cultures of C. dewevrei recovered the ability to synthesize caffeine almost in similar levels of C. arabica cultures. Tracer experiments with labelled carbon dioxide showed a significant accumulation of radioactivity in caffeine and metabolites, indicating an active biosynthesis. When the cultures were fed with labelled caffeine most of the radioactivity was recovered in caffeine, indicating that although active, degradation was not so efficient as in leaves, and therefore,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coffee; Caffeine; Cell suspension culture; Methylxanthines. |
| Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132000000100009 |
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| SETOTAW, T. A.; NUNES, C. F.; SOUZA, C. S. de; SALGADO, S. L.; CARVALHO, G. R.; REZENDE, J. C. de; PEREIRA, A. A.; CANÇADO, G. M. de A.. |
| O banco de germoplasma de café da EPAMIG contém acessos muito importantes para o programa de melhoramento de Coffea arabica, os quais necessitam de caracterização em relação aos ácidos orgânicos e cafeína. Portanto, esse trabalho objetivou avaliar 64 acessos de C. arabica, C. canephora var. Robusta e Híbrido de Timor mantidos no banco de germaplasma localizado na Fazenda Experimental da EPAMIG no município de Patrocínio/MG. A avaliação foi baseada na quantificação do ácido clorogênico, trigonelina e cafeína por meio da determinação empregando HPLC Perkins Elmer com ?UV/VIS detector?. Detectou-se variabilidade em relação ao ácido clorogênico, trigonelina e cafeína entre acessos de café arábica e os outros acessos do banco de germoplasma. Isso evidencia a... |
| Tipo: Anais e Proceedings de eventos |
Palavras-chave: Ácidos orgânicos; Cromatografia líquida de alta eficiência; Organic Acids.; Cafeína; Coffea Arábica.; Caffeine; High performance liquid chromatography.. |
| Ano: 2015 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1036538 |
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| Rios,Teodulo Salinas; Torres,Teresa Sánchez; Cerrilla,María Esther Ortega; Hernández,Marcos Soto; Cruz,Antonio Díaz; Bautista,Jorge Hernández; Cuéllar,Cuauhtémoc Nava; Huerta,Humberto Vaquera. |
| The objective of the present study was to determine the nutritive value, the presence of antioxidant compounds, and the antioxidant capacity of coffee pulp ensiled or non-ensiled. Dry matter (DM), crude protein (CP), ash, acid detergent fiber (ADF), neutral detergent fiber (NDF), and lignin, as well as the antioxidant compounds present in coffee pulp and their antioxidant capacity, were determined. A completely randomized design was used. Data were analyzed by analysis of variance. Ensiling of coffee pulp increased the CP content from 98.6 to 111.6 g kg−1 DM, NDF from 414.6 to 519.5 g kg−1 DM, ADF from 383.9 to 439.3 g kg−1 DM, and lignin from 122.9 to 133.6 g kg−1 DM. Caffeine decreased from 5.72 to 5.02 mg g−1 DM. Three antioxidant compounds were... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Caffeic; Caffeine; Chlorogenic; Gallic acid; Silage; Trolox. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982014000900492 |
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| Benatti,Luciana Benjamim; Silvarolla,Maria Bernadete; Mazzafera,Paulo. |
| We compared the biochemical characteristics of the beans of a naturally decaffeinated Arabica coffee (AC1) discovered in 2004 with those of the widely grown Brazilian Arabica cultivar "Mundo Novo" (MN). Although we observed differences during fruit development, the contents of amino acids, organic acids, chlorogenic acids, soluble sugars and trigonelline were similar in the ripe fruits of AC1 and MN. AC1 beans accumulated theobromine, and caffeine was almost entirely absent. Tests on the supply of [2-14C] adenine and enzymatic analysis of theobromine synthase and caffeine synthase in the endosperm of AC1 confirmed that, as in the leaves, caffeine synthesis is blocked during the methylation of theobromine to caffeine. The quality of the final coffee... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coffea arabica; Caffeine; Decaffeination; Beverage quality. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052012000200001 |
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| Cardoso-Lopes,Elaine Monteiro; Paula,Daisy Maria Bentes de; Barbo,Fausto Erritto; Souza,Amanda de; Blatt,Cecília Terumi Teradaira; Torres,Luce Maria Brandão; Young,Maria Cláudia Marx. |
| Pera glabrata (Schott) Baill. was selected for this study after showing a preliminary positive result in a screening of Atlantic Forest plant species in the search for acetylcholinesterase inhibitors and antifungal compounds. The bioassays were conducted with crude ethanol extract of the leaves using direct bioautography method for acetylcholinesterase and antifungal activities. This extract was partitioned with hexane, chloroform and ethyl acetate solvents. The active chloroform fraction was submitted to silica gel chromatography column affording 12 groups. Caffeine, an alkaloid, which showed detection limits of 0.1 and 1.0 µg for anticholinesterasic and antifungal activities, respectively, was isolated from group nine. After microplate analyses, only... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: 9-hydroxy-4-megastigmen-3-one; Biological activities; Caffeine; Euphorbiaceae. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042009000400019 |
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| Machado,Silmara Rodrigues; Parise,Edison Roberto; Carvalho,Luciana de. |
| The potential role of coffee as a hepatoprotective substance for chronic liver diseases has been widely discussed. Our main aim was to evaluate the effect of coffee intake regarding clinical, biochemical tests and liver biopsy data in treatment naïve patients with chronic hepatitis C. One hundred and thirty-six patients with chronic hepatitis C, diagnosed through liver biopsy, or by means of clinical, ultrasound or endoscopic signs of cirrhosis, were assessed by determination of biochemical tests, metabolic and morphological alterations. Food frequency was scrutinized by using a structured questionnaire. Coffee intake represented more than 90% of the total daily caffeine, and the 75th percentile was 4-Brazilian coffee-cup/day (>255mL/day or >123mg... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coffee; Caffeine; Hepatitis C; Fibrosis. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702014000200170 |
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| Gourmelon, Michele; Caprais, Marie-paule; Mieszkin, Sophie; Marti, Romain; Wery, Nathalie; Jarde, E.; Derrien, Marc; Jadas-hecart, A.; Communal, P. Y.; Jaffrezic, A.; Pourcher, A. M.. |
| The microbiological quality of coastal or river waters can be affected by faecal pollution from human or animal sources. An efficient MST (Microbial Source Tracking) toolbox consisting of several host-specific markers would therefore be valuable for identifying the origin of the faecal pollution in the environment and thus for effective resource management and remediation. In this multidisciplinary study, after having tested some MST markers on faecal samples, we compared a selection of 17 parameters corresponding to chemical (steroid ratios, caffeine, and synthetic compounds), bacterial (host-specific Bacteroidales, Lactobacillus amylovorus and Bifidobacterium adolescentis) and viral (genotypes I-IV of F-specific bacteriophages, FRNAPH) markers on... |
| Tipo: Text |
Palavras-chave: Microbial source tracking; Faecal pollution; Bacteroidales; Bifidobacterium adolescentis; Lactobacillus; FRNA bacteriophages; Steroids; Caffeine. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00016/12710/9690.pdf |
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| Reis,A.M.S.; Oliveira,K.P.; Paula,I.H.F.; Silva,A.P.; Tarragô,J.F.; Ocarino,N.M.; Serakides,R.. |
| ABSTRACT The aim of this study was to evaluate the effect of concentrations of caffeine on the viability, synthesis activity and gene expression in cultures of chondrocytes. Extracted articular cartilage from the femurs and tibias of 15 Wistar rats at three days old to isolate chondrocytes. Chondrocytes were cultured in chondrogenic medium (control) or supplemented with caffeine (0.5, 1.0, 2.0mM). Cell viability, alkaline phosphatase activity and collagen synthesis were assessed using colorimetric assays at 7, 14, 21 days. The chondrocyte cultures of all groups grown under coverslips were stained with hematoxylin-eosin to determine the percentage of cells/field and with PAS, safranin O, alcian blue to determine the percentage of matrix chondrogenic/field... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Rats; Caffeine; Chondrocytes; Chondrogenesis. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352019000200509 |
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| Del Campo,A.; Bracho,M.; Marcano,L.; Guíñez,J.; De la Torre,C.. |
| This work evaluated the qualitative and quantitative cellular changes induced by treatment with 5-aminouracil (5-AU) and a combination of 5-AU and caffeine in plant cells in relation to DNA damage, repaired damage, and residual damage. As biological material, Allium cepa L. root tips were used, grown in filtered water, in darkness, with aeration at constant temperature of 25 °C ± 0.5. Cell populations were synchronized using 5 mM caffeine in order to study the effects of 5-AU and caffeine/5-AU combined treatment on the DNA content and their incidence in the entrance to mitosis. The results showed a delay in the G2 period due to induced DNA damage by the 5-AU and caffeine/5-AU combined treatment, shown by aberrant metaphases, anaphases and telophases. The... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: 5-aminouracil; G2 checkpoints; Caffeine. |
| Ano: 2005 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452005000200003 |
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| Fan,Leifa; Soccol,Andréa Thomaz; Pandey,Ashok; Vandenberghe,Luciana Porto de Souza; Soccol,Carlos Ricardo. |
| The objective of this work was to study the effect of caffeine and tannins on Pleurotus sp. cultivation and to evaluate the feasibility of using coffee husks as substrate for mushroom cultivation. Eight strains of P. ostreatus and two strains of P. sajor-caju were screened on a medium prepared from agar extract of coffee husk. Based on best mycelial growth and biomass production, the strain P. ostreatus LPB 09 was selected for detailed studies. With the increase of caffeine concentration, the mycelial growth and the biomass production decreased, and no growth was observed when concentration of caffeine was 2500 mg/L. Furthermore, Pleurotus did not degrade the caffeine, but absorbed it. Tannin under 100 mg/L in the medium stimulated the growth of mycelia,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cultivation; Pleurotus; Caffeine; Tannin; Detoxification. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822006000400003 |
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| Rodriguez,Yeison F. B.; Guzman,Nelson G.; Hernandez,Joel G.. |
| ABSTRACT The objective of this work was to study the influence of two postharvest processing methods on the biochemical composition and sensory analysis of a Colombian specialty coffee. For this purpose, coffee beans (Coffea arabica) of the Castillo variety were collected and processed using the wet and semi-dry methods, and the drying process was conducted in a sun drier prototype with a plastic parabolic cover, with a maximum drying air temperature of 50 °C; green coffee beans were managed according to the official Specialty Coffee Association cupping protocol and roasted to a medium and dark degree. Physicochemical determinations (pH, color, titratable acidity, caffeine content, and chlorogenic acid quantification) in green coffee and roasted coffee... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Caffeine; Coffee roasting; Coffee processing; Cup quality; Chlorogenic acids. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000200177 |
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| Registros recuperados: 54 | |
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