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1.
Mod Pathol ; 29(2): 194-208, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26743476

RESUMEN

Intestinal metaplasia in gastric mucosa is considered a preneoplastic lesion that progresses to gastric cancer. However, the molecular networks underlying this lesion formation are largely unknown. NKX6.3 is known to be an important regulator in gastric mucosal epithelial differentiation. In this study, we characterized the effects of NKX6.3 that may contribute to gastric intestinal metaplasia. NKX6.3 expression was significantly reduced in gastric mucosae with intestinal metaplasia. The mRNA expression levels of both NKX6.3 and CDX2 predicted the intestinal metaplasia risk, with an area under the receiver operating characteristic curve value of 0.9414 and 0.9971, respectively. Notably, the NKX6.3 expression level was positively and inversely correlated with SOX2 and CDX2, respectively. In stable AGS(NKX6.3) and MKN1(NKX6.3) cells, NKX6.3 regulated the expression of CDX2 and SOX2 by directly binding to the promoter regions of both genes. Nuclear NKX6.3 expression was detected only in gastric epithelial cells without intestinal metaplasia. Furthermore, NKX6.3-induced TWSG1 bound to BMP4 and inhibited BMP4-binding activity to BMPR-II. These data suggest that NKX6.3 might function as a master regulator of gastric differentiation by affecting SOX2 and CDX2 expression and the NKX6.3 inactivation may result in intestinal metaplasia in gastric epithelial cells.


Asunto(s)
Transdiferenciación Celular , Transformación Celular Neoplásica/genética , Silenciador del Gen , Proteínas de Homeodominio/genética , Lesiones Precancerosas/genética , Factores de Transcripción SOXB1/genética , Neoplasias Gástricas/genética , Factores de Transcripción/genética , Animales , Antígenos Bacterianos/genética , Antígenos Bacterianos/metabolismo , Área Bajo la Curva , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Sitios de Unión , Proteína Morfogenética Ósea 4/genética , Proteína Morfogenética Ósea 4/metabolismo , Factor de Transcripción CDX2 , Línea Celular Tumoral , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Modelos Animales de Enfermedad , Femenino , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiología , Mucosa Gástrica/patología , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , Infecciones por Helicobacter/genética , Infecciones por Helicobacter/metabolismo , Infecciones por Helicobacter/patología , Helicobacter pylori/genética , Helicobacter pylori/metabolismo , Proteínas de Homeodominio/metabolismo , Humanos , Metaplasia , Ratones Endogámicos C57BL , Fenotipo , Lesiones Precancerosas/metabolismo , Lesiones Precancerosas/microbiología , Lesiones Precancerosas/patología , Regiones Promotoras Genéticas , Proteínas/genética , Proteínas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Curva ROC , Medición de Riesgo , Factores de Riesgo , Factores de Transcripción SOXB1/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/patología , Factores de Transcripción/metabolismo , Transfección
2.
Artículo en Inglés | MEDLINE | ID: mdl-21966298

RESUMEN

Propolis is a resinous product collected by honey bees. It was also reported that propolis has a wide variety of biological actions, including antimicrobial activity and antioxidant, anti-inflammatory, and suppressive effects of dioxin toxicity activities. The aim of this study was to compare the in vitro cytotoxic activities of green propolis (G12) and red propolis (G13) in human leukemia cells. These cells were incubated with different concentrations of propolis and 48 hours after the IC(50) was calculated for each cell. The results showed that the red propolis has cytotoxic effect in vitro higher than green propolis. Red propolis was showed to be cytostatic in K562 cells and caused the same amount of apoptosis as its control Gleevec. In conclusion, these results showed that red propolis is more cytotoxic than the green propolis in a variety of human cell lines of leukemia. Red propolis may contain drugs capable of inhibiting cancer cell growth. Therefore, further isolation of respective chemical ingredients from the red propolis (G13) for identification of the activities is necessary.

3.
Int J Oncol ; 31(3): 601-6, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17671687

RESUMEN

Propolis is a resinous substance collected by bees (Apis mellifera) from various tree buds which they then use to coat hive parts and to seal cracks and crevices in the hive. Propolis, a known ancient folk medicine, has been extensively used in diet to improve health and to prevent disease. In the present study, we have evaluated the effects of ethanolic extracts of Brazilian propolis group l2 and bud resins of botanical origin (B. dracunculifolia), and propolis group 3 on proliferation of metastasis (DU145 and PC-3) and primary malignant tumor (RC58T/h/SA#4)-derived human prostate cancer cells. The strongest inhibition was observed in propolis group 3 (sample #3) extracts whereas moderate growth inhibition was observed in human prostate epithelial cells. In the RC58T/h/SA#4 cells, resins of botanical origin of propolis group 12 (sample #1) and propolis group 12 (sample #2) induced growth inhibition that was associated with S phase arrest whereas propolis group 3 (sample #3) induced growth inhibition that was associated with G2 arrest. The mechanisms of cell cycle effects of propolis were investigated. The resins of botanical origin of propolis group 12 and propolis group 12 showed similar inhibition of cyclin D1, CDK4 and cyclin B1 expression. Propolis group 3 showed higher induction of p21 expression but no inhibition of cyclin D1, CDK4 and cyclin B1 expression. The results obtained here demonstrate that the Brazilian propolis extracts have significant inhibitory effect on proliferation of human prostate cancer cells. Inhibition was achieved through regulation of protein expression of cyclin D1, B1 and cyclin dependent kinase (CDK) as well as p21. Our results indicate that the Brazilian propolis extracts show promise as chemotherapeutic agents as well as preventive agents against prostate cancer.


Asunto(s)
Etanol/farmacología , Regulación Neoplásica de la Expresión Génica , Extractos Vegetales/farmacología , Própolis/metabolismo , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Antineoplásicos/farmacología , Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Ciclina B/biosíntesis , Ciclina B1 , Ciclina D1/biosíntesis , Quinasa 4 Dependiente de la Ciclina/biosíntesis , Humanos , Masculino , Neoplasias de la Próstata/metabolismo
4.
Curr Drug Discov Technol ; 14(2): 127-134, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28000555

RESUMEN

BACKGROUND: Propolis has been used as a natural health product mainly due to the presence of polyphenols, flavonoids, phenolic aldehydes, amino acids, vitamins and others bioactive constituents. To this natural substance are attributed different biological and pharmacological properties which are influenced by its chemical composition and organoleptic properties. The aim of this work was to evaluate the physicochemical properties and parameters of green propolis collected during a period of six years (2008-2013) in the state of Minas Gerais, located at the southeastern region of Brazil. METHODS: The methodology were in accordance with Brazilian legislation on the identity and quality standards of propolis. The evaluated parameters of hydroalcoholic from green propolis were total flavonoids, antioxidant activity - DPPH method, oxidation index, wax content, humidity and insoluble impurities. RESULTS: Propolis samples collected in different seasons during the years 2008 to 2013 presented mean values of total flavonoids (3.4 ± 0.11 mg/g), antioxidant activity DPPH (4.76 ± 0.16 µg/mL), oxidation index (3, 4 ± 0.33 seconds) and wax (15.14 ± 0.78% m/m), which are in accordance with Brazilian legislation. CONCLUSION: Green propolis did not show abrupt seasonal changes during the six years of investigation, and may be considered as an adequate functional ingredient.


Asunto(s)
Própolis/química , Antioxidantes/química , Baccharis , Compuestos de Bifenilo/química , Brasil , Flavonoides/análisis , Fenoles/análisis , Picratos/química , Estaciones del Año , Ceras/análisis
5.
J Agric Food Chem ; 53(4): 1166-72, 2005 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-15713035

RESUMEN

Twenty-five samples of propolis were collected from seven different regions in northern Argentina; ethanolic extracts of propolis were prepared from all samples, and the respective samples were examined for UV absorption spectra, RPHPTLC, RPHPLC, antimicrobial activity, antiradical activity, and total phenolic content. It was found that 16 of the 25 samples showed a phenolic profile similar to that found in samples from southern Brazil and corresponding to poplar-based propolis and that the rest of the samples showed a different profile and higher antimicrobial and antiradical activities.


Asunto(s)
Própolis/química , Própolis/farmacología , Antibacterianos/análisis , Argentina , Cromatografía Líquida de Alta Presión , Etanol , Flavonoides/análisis , Radicales Libres/antagonistas & inhibidores , Fenoles/análisis , Espectrofotometría Ultravioleta
6.
J Agric Food Chem ; 53(26): 10306-9, 2005 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-16366731

RESUMEN

Suppressive effects of ethanolic extracts prepared from propolis group 12 and its main botanical origin (leaf bud of Baccharis dracunculifolia) on transformation of the aryl hydrocarbon receptor (AhR), the initial action of dioxin toxicity, were investigated. It was found that suppressive effects of propolis on AhR transformation were relatively higher than those of resins of its botanical origin in cell-free system and in Hepa-1c1c7 cells. When the composition of chemical ingredients was measured, propolis contained slightly higher amounts of flavonoid aglycones as compared with its botanical origin with the same characteristics. Moreover, antiradical activity, one of the typical biological activities of flavonoids, in propolis was also slightly higher than that in its botanical origin. These results indicate that not only propolis but also its botanical origin contains high amounts of flavonoid aglycones and that both of them are useful dietary sources for flavonoids with a potency to prevent dioxin toxicity.


Asunto(s)
Baccharis/metabolismo , Dioxinas/antagonistas & inhibidores , Dioxinas/toxicidad , Própolis/farmacología , Animales , Línea Celular Tumoral , Sistema Libre de Células , Cromatografía Líquida de Alta Presión , Ensayo de Inmunoadsorción Enzimática , Etanol , Flavonoides/análisis , Depuradores de Radicales Libres/farmacología , Ratones , Hojas de la Planta/química , Dibenzodioxinas Policloradas/antagonistas & inhibidores , Dibenzodioxinas Policloradas/farmacología , Própolis/química , Própolis/metabolismo , Receptores de Hidrocarburo de Aril/metabolismo , Resinas de Plantas/farmacología , Solventes
7.
J Agric Food Chem ; 50(9): 2502-6, 2002 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-11958612

RESUMEN

Brazilian propolis has been classified into 12 groups based on physicochemical characteristics: five in the southern Brazil group (group 3), one in the southeastern Brazil group (group 12), and six in the northeastern Brazil group (group 6). The plant origins of these groups were investigated using reversed-phase high-performance thin-layer chromatography (RPHPTLC), reversed-phase high-performance liquid chromatography (RPHPLC), and gas chromatography-mass spectrometry (GC-MS). It was concluded that the origins of propolis group 3, group 6, and group 12 are resins of the poplar tree, Hyptis divaricata, and Baccharis dracunculifolia, respectively.


Asunto(s)
Própolis/química , Animales , Abejas , Brasil , Fenómenos Químicos , Química Física , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Hojas de la Planta/química , Estructuras de las Plantas/química , Própolis/análisis , Resinas de Plantas/análisis , Árboles
8.
J Agric Food Chem ; 52(5): 1100-3, 2004 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-14995105

RESUMEN

Previously, it was reported that one group of propolis (Group 12) was identified in southeastern Brazil, and the botanical origin of the propolis was Baccharis dracunculifolia resinous exudates. It was also observed that honeybee (Africanized Apis mellifera) mainly visited the leaf buds or unexpanded leaves of B. dracunculifolia but rarely expanded leaves. B. dracunculifolia is dioecious with male and female inflorescences, and RPHPLC of the ethanolic extracts of the respective male and female bud resinous exudates showed the same profiles. RPHPLC profiles of propolis G12 leaf buds and unexpanded and expanded leaves of B. dracunculifolia showed similarity, but unexpanded leaves quantitatively decreased in chemical constituents as compared with leaf buds. In the case of expanded leaves, all chemical constituents were severely decreased or disappeared. Artepillin C (3,5-diprenyl-4-hydroxycinnamic acid) was also identified in both propolis and resinous exudates, and both ethanolic extracts contained the highest concentrations of this compound as compared with the rest of the chemical constituents.


Asunto(s)
Baccharis/química , Própolis/análisis , Animales , Antiinfecciosos/análisis , Abejas , Brasil , Cromatografía Líquida de Alta Presión , Flavonoides/análisis , Fenoles/análisis , Hojas de la Planta/química
9.
Evid Based Complement Alternat Med ; 5(4): 435-41, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18955226

RESUMEN

Propolis contains resinous substances collected by honey bees from various plant sources and has been used as a traditional folk medicine since ca 300 BC. Nowadays, the use of evidence-based complementary and alternative medicine (CAM) is increasing rapidly and so is the use of propolis in order to treat or support the treatment of various diseases. Much attention has been focused on propolis from Populus sp. (Salicaceae) and Baccharis dracunculifolia (Asteracea), but scientific information about the numerous other types of propolis is still sparse. We gathered six samples of red propolis in five states of Northeastern Brazil. The beehives were located near woody perennial shrubs along the sea and river shores. The bees were observed to collect red resinous exudates on Dalbergia ecastophyllum (L) Taub. (Leguminosae) to make propolis. The flavonoids of propolis and red resinous exudates were investigated using reversed-phase high-performance liquid chromatography and reversed-phase high-performance thin-layer chromatography. We conclude that the botanical origin of the reddish propolis is D. ecastophyllum. In areas where this source (D. ecastophyllum) was scarce or missing, bees were collecting resinous material from other plants. Propolis, which contained the chemical constituents from the main botanical origin, showed higher antimicrobial activity.

10.
Antimicrob Agents Chemother ; 46(5): 1302-9, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11959560

RESUMEN

Propolis, a resinous bee product, has been shown to inhibit the growth of oral microorganisms and the activity of bacterium-derived glucosyltransferases (GTFs). Several compounds, mainly polyphenolics, have been identified in this natural product. The present study evaluated the effects of distinct chemical groups found in propolis on the activity of GTF enzymes in solution and on the surface of saliva-coated hydroxyapatite (sHA) beads. Thirty compounds, including flavonoids, cinnamic acid derivatives, and terpenoids, were tested for the ability to inhibit GTFs B, C, and D from Streptococcus mutans and GTF from S. sanguinis (GTF Ss). Flavones and flavonols were potent inhibitors of GTF activity in solution; lesser effects were noted on insolubilized enzymes. Apigenin, a 4',5,7-trihydroxyflavone, was the most effective inhibitor of GTFs, both in solution (90.5 to 95% inhibition at a concentration of 135 microg/ml) and on the surface of sHA beads (30 to 60% at 135 microg/ml). Antibacterial activity was determined by using MICs, minimum bactericidal concentrations (MBCs), and time-kill studies. Flavanones and some dihydroflavonols, as well as the sesquiterpene tt-farnesol, inhibited the growth of S. mutans and S. sobrinus; tt-farnesol was the most effective antibacterial compound (MICs of 14 to 28 microg/ml and MBCs of 56 to 112 microg/ml). tt-Farnesol (56 to 112 microg/ml) produced a 3-log-fold reduction in the bacterial population after 4 h of incubation. Cinnamic acid derivatives had negligible biological activities. Several of the compounds identified in propolis inhibit GTF activities and bacterial growth. Apigenin is a novel and potent inhibitor of GTF activity, and tt-farnesol was found to be an effective antibacterial agent.


Asunto(s)
Glucosiltransferasas/antagonistas & inhibidores , Própolis/química , Própolis/farmacología , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/crecimiento & desarrollo , Animales , Abejas , Cinamatos/química , Cinamatos/farmacología , Durapatita , Flavonoides/química , Flavonoides/farmacología , Glucosiltransferasas/metabolismo , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Saliva/enzimología , Streptococcus mutans/enzimología , Terpenos/química , Terpenos/farmacología
11.
Caries Res ; 36(6): 445-8, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12459618

RESUMEN

The aim of this study was to evaluate the effect of a mouthrinse containing propolis SNB-RS on 3-day dental plaque accumulation. Six volunteers took part in a double-blind crossover study performed in two phases of 3 days. During each phase the volunteers refrained from all oral hygiene and rinsed with 20% sucrose solution 5 times a day to enhance dental plaque formation and with mouthrinse (placebo or experimental) twice a day. On the 4th day, the plaque index (PI) of the volunteers was scored and the supragingival dental plaque was analyzed for insoluble polysaccharide (IP). The PI (SD) for the experimental group was 0.78 (0.17), significantly less than for the placebo group, 1.41 (0.14). The experimental mouthrinse reduced the IP concentration in dental plaque by 61.7% compared to placebo (p < 0.05). An experimental mouthrinse containing propolis SNB-RS was thus efficient in reducing supragingival plaque formation and IP formation under conditions of high plaque accumulation.


Asunto(s)
Antiinfecciosos Locales/uso terapéutico , Placa Dental/prevención & control , Antisépticos Bucales/uso terapéutico , Própolis/uso terapéutico , Adulto , Estudios Cruzados , Placa Dental/metabolismo , Método Doble Ciego , Femenino , Glucosiltransferasas/antagonistas & inhibidores , Humanos , Masculino , Polisacáridos/metabolismo , Própolis/farmacología , Estadísticas no Paramétricas
12.
Biosci Biotechnol Biochem ; 68(4): 935-8, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15118327

RESUMEN

Present study demonstrated that the ethanolic extracts of propolis containing higher concentrations of flavonoids suppressed 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced aryl hydrocarbon receptor transformation in a dose-dependent manner. The IC(50) values of propolis group 3 and group 12 were 1.2 and 3.6 microg/ml, respectively, indicating that propolis showed stronger antagonistic effects as compared with vegetable extracts.


Asunto(s)
Etanol/química , Dibenzodioxinas Policloradas/antagonistas & inhibidores , Dibenzodioxinas Policloradas/farmacología , Própolis/química , Própolis/farmacología , Receptores de Hidrocarburo de Aril/metabolismo , Animales , Relación Dosis-Respuesta a Droga , Flavonoides/química , Flavonoides/farmacología , Frutas/química , Regulación de la Expresión Génica/efectos de los fármacos , Concentración 50 Inhibidora , Extractos Vegetales/química , Extractos Vegetales/farmacología , Ratas , Supresión Genética/genética , Verduras/química
13.
Rev. microbiol ; 23(3): 183-8, jul.-set. 1992. tab, graf
Artículo en Portugués | LILACS | ID: lil-279942

RESUMEN

Uma linhagem termofílica do fungo Aspergillus sp., No.10-2, foi isolada de compostos.a faixa de temperatura para crescimento variou de 20 a 50ºC sendo que a temperatura ótima ficou entre 35 a 45ºC.As produçöes máximas de endo-1, 4-ß-D-glucanase EC.3.2.1.4 (CMCase), exo-1, 4-ß-D-cellobiohydrolase EC. 3.2.1.91 (Avicelase) e ß-glucosidase EC.3.2.1.21 (Celobiase)foram obtidas quando o fungo foi cultivado em meio líquido contendo papel de celulose em pó.A maior produçäo de CMCase foi obtida a 37ºC enquanto que uma extraordinária produçäo de ß-glucosidase ocorreu a 45ºC.A temperatura ótima de sacarificaçäo de celulose pela enzima foi 55ºC.Ensaios de cromatografia de papel de hidrolisados da celulose demonstraram predominantemente glicose quando comparado a hidrolisados de celulose obtidos por enzima de Trichoderma reesei QM 9414.Isto ocorreu porque a linhagem de Aspergillus sp., No.10-2, produziu maiores a enzima ß-glucosidase


Asunto(s)
Aspergillus/crecimiento & desarrollo , Temperatura , Trichoderma/crecimiento & desarrollo , beta-Glucosidasa
14.
Rev. microbiol ; 24(1): 71-2, mar. 1993. ilus
Artículo en Portugués | LILACS | ID: lil-280146

RESUMEN

Foi isolada uma nova linhagem de Saccharomyces cerevisuiae 337, de usina de cana de açucar, que apresentou ativudade "Killer" semelhante ao fenótipo K.A eletroforese em gel de agarose mostrou que a linhagem S.cerevisiae 337 possui dois ds-RNAs. A atividade "killer" da linhagem foi comparada com a levedura padräo"Killer" K


Asunto(s)
Saccharomyces cerevisiae/crecimiento & desarrollo , Levaduras/clasificación , Levaduras/química , Línea Celular/citología , Línea Celular/clasificación , Electroforesis , Técnicas In Vitro , Plásmidos/clasificación
15.
Rev. microbiol ; 25(2): 112-8, abr.-jun. 1994. ilus
Artículo en Inglés | LILACS | ID: lil-147945

RESUMEN

A linhagem termófila Humicola sp., que foi isolada de madeira em decomposiçäo, produz xilanases extracelulares termoestáveis a 50oC. As xilanases foram purificadas e foram encontradas 3 fraçöes de proteínas com atividade de xilanase. As características das 3 xilanases foram estudadas. Verificou-se que a xilanase I é uma endoxilanase; a xilanase II é uma xilosidase (exoxilanase) enquanto que a xilanase III é uma endoxilanase que também apresenta atividade de arabinosidase e CMCase. O tratamento da polpa "Kraft" branqueada obtida de eucalipto com enzima purificadas e bruta aumentou o brilho da polpa quando comparada com a polpa sem este tratamento. Xilanase I e xilanase bruta aumentaram a viscosidade da polpa enquanto xilanase II e III diminuíram a viscosiddade devido à presença de atividade CMCase


Asunto(s)
Madera , Enzimas/clasificación , Hongos/aislamiento & purificación , Enzimas/aislamiento & purificación
16.
Arq. biol. tecnol ; 40(1): 97-106, mar. 1997. ilus, tab
Artículo en Inglés | LILACS | ID: lil-240737

RESUMEN

Forty-six specimens of propolis which were collected by Apis mellifera were obtained from various regions of Brazil and extracted with 80 per cent aqueous ethanol(ethanolic extract of propolis, EEP). The extracts were analysed by using determination of total flavonoid concentrations using the aluminum nitrate method, UV-spectrophotometry, reversed phase-high performance thin layer chromatography (HPTLC), and reversed phase-HPLC. Six samples of EEP, which contained high total flavonoid concentrations, were selected for futher investigation. HPTLC indicated that the quality of flavonoid aglycones of EEP from the States of Minas Gerais and Säo Paulo (Southeastern Brazil), Goias and Mato Grosso do Sul (closely to Southeastern) were similar, but were different compared to those of EEP's from Paraná and Rio Grande do Sul, which are located in Southern Brazil. Reversed Phase-HPLC analysis of EEP's from Southern Brazil identified 7 flavonoid aglycones, whereas there were 9 from Säo Paulo and Minas Gerais and 7 from Goiás and Mato Grosso do Sul. These results indicate that the plant ecology of Southeastern and Southern Brazil are different. It was also observed that all samples of EEP's demonstrated inhibition of growth of Staphylococcus aureus coagulase positive, whereas Escherichia coli was not inhibited


Asunto(s)
Abejas , Cromatografía , Tecnología de Alimentos , Própolis
17.
Rev. microbiol ; 26(1): 41-5, jan.-mar. 1995. ilus, tab
Artículo en Portugués | LILACS | ID: lil-283827

RESUMEN

A enzima amilolítica de Candida sp. ATCC 90238 foi purificada e suas características enzimáticas foram estudadas. O peso molecular da enzima purificada foi estimado em 120.000. A cromatografia em papel do hidrolizado de amido solúvel indicou que a enzima é uma amiloglicosidase. Maltotriose e amido solúvel foram eficientemente hidrolisados a glicose pela enzima, enquanto que a maltose foi menos eficiente como substrato. A enzima apresenta características diferentes quando comparada à amiloglicosidase de Aspergillus e Rhizopus sp. que hidrolisam completamente a maltose. Esta enzima é adequada para a produçäo de xarope de glicomaltose.


Asunto(s)
Aspergillus , Rhizopus/efectos de los fármacos , Candida/enzimología , Activadores de Enzimas , Enzimas/biosíntesis
18.
Caries res ; 35(5): 418-26, Sept.-Oct. 2000. ilus
Artículo en Portugués | BBO - odontología (Brasil) | ID: biblio-850595

RESUMEN

Propolis, a resinous hive product collected by Apis mellifera bees, has been used for thousands of years in folk medicine. Ethanolic extracts of propolis (EEP) have been shown to inhibit the activity of a mixture of crude glucosyltransferase (Gtf) enzymes in solution. These enzymes synthesize glucans from sucrose, which are important for the formation of pathogenic dental plaque. In the present study, the effects of propolis from two different regions of Brazil on the activity of separate, purified Gtf enzymes in solution ans on the surface of saliva-coated hydroxyapatite (sHA) beads were evaluated. The EEP from Minas Gerais (MG; Southeastern Brazil) and Rio Grande do Sul (RS; Southern Brazil) were tested for their ability to inhibit the enzymes GtfB (synthesis of insoluble glucan), GtfC (insoluble/soluble glucan) and GtfD (soluble glucan). The effects of propolis on Gtf from Streptococcus sanguis (soluble glucan synthesis) was also explored...


Asunto(s)
Durapatita , Glucanos , Glucosiltransferasas , Hidroxiapatitas , Própolis
19.
Caries res ; 36(6): 445-8, Nov.-Dec. 2002. tab
Artículo en Portugués | BBO - odontología (Brasil) | ID: biblio-850601

RESUMEN

The aim of this study was to evaluate the effect of a mouthrinse containing propolis SNB-RS on 3-day dental plaque accumulation. Six volunteers took part in a double-blind crossover study performed in two phases of 3 days. During each phase the volunteers refrained from all oral hygiene and rinsed with 20 percent sucrose solution 5 times a day to enhance dental plaque formation and with mouthrinse (placebo or experimental) twice a day. On the 4th day, the plaque index (PI) of the volunteers was scored and the supragingival dental plaque was analyzed for insoluble polysaccharide (IP). The PI (SD) for the experimental group was 0.78 (0.17), significantly less than for the placebo group, 1.41 (0.14). The experimental mouthrinse reduced the IP concentration in dental plaque by 61.7 percent compared to placebo (p < 0.05). An experimental mouthrinse containing propolis SNB-RS was thus efficient in reducing supragingival plaque formation and IP formation under conditions of high plaque accumulation


Asunto(s)
Placa Dental , Antisépticos Bucales
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