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1.
Nat Prod Res ; 34(2): 241-250, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30449169

RESUMO

Gakolanone (3',5'-digeranyl-2',4',6',3-tetrahydroxybenzophenone; 1), a novel benzophenone derivative was isolated from the hexane extract of Garcinia kola Heckel stem-bark along with three known 3-8'' linked biflavonoids: 3'',4',4''',5,5'',7,7''-heptahydroxy-3,8''-biflavanone (2); 3'',4',5,5'',5''',7,7''-heptahydroxy-4-methoxy-3,8''-biflavanone (3) and 4',4''',5,5'',7,7''-hexahydroxy-3,8''-biflavanone (4) from the ethanol extract. The compounds were characterized primarily using 1 D and 2 D nuclear magnetic resonance spectroscopy and mass spectrometry and by comparing with literature. The compounds were subjected to in-vitro alpha-amylase enzyme inhibitory assay using DNSA (3,5-dinitrosalicylic acid) reagent with acarbose used as the standard drug. All the compounds were found to show alpha-amylase inhibitory activities with IC50 of 21.4 ± 1.5, 9.9 ± 0.2, 15.3 ± 2.3, 12.9 ± 2.3 µg/mL respectively. All the compounds exhibited better alpha-amylase inhibitory activities than the standard drug, acarbose (IC50= 38.1 ± 8.3 µg/mL).


Assuntos
Benzofenonas/isolamento & purificação , Garcinia kola/química , Benzofenonas/farmacologia , Biflavonoides/química , Biflavonoides/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Concentração Inibidora 50 , Casca de Planta/química , Extratos Vegetais/química , alfa-Amilases/antagonistas & inibidores
3.
J Toxicol Environ Health A ; 63(5): 351-62, 2001 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-11471866

RESUMO

Chromium is found in soil from natural sources and anthropogenic activities. The ingestion of soil contaminated with chromium especially by children can have toxic consequences. Therefore, it is important to quantify the oral bioaccessibility of chromium in chromium in contaminated soil. In this study, chromium-51 as chromic (III) chloride and sodium chromate (VI), was mixed with an Atsion sandy soil and a Keyport clay soil and stored for 4 mo at either 21-25 degrees C or 2-4 degrees C. Utilizing simulated gastric conditions, the oral bioaccessibility of chromium in soil was determined. When the effects of soil on the bioaccessibility of chromium were compared, the data revealed the the bioaccessibility of chromium (III) from the clay soil was significantly lower than from the sandy at 21-25 degrees C. However, at 2-4 degrees C, more chromium (III) was extracted by synthetic gastric fluid from the clay soil than from the sandy soil. Temperature was also a factor as evidenced by the higher bioaccessibility of chromium (IV) in the sandy soil at 2-4 degrees C and of both chromium species in the clay soil at the same temperature. Reduction of the soluble chromium (VI) chemical to the nonsoluble chromium (III) compound in the acidic soils by naturally occurring organic matter in soil would explain the lower bioaccessibilty of chromium (VI) at 21-25 degrees C. At 2-4 degrees C, the data indicate that the rate of chromium (VI) reduction to chromium (III) was slowed. Although the results of this study are limited to one low concentration of chromium (III) and chromium (VI) and indicate that the bioaccessibility of chromium in soil can range between 18% and 72%, the data also suggest that there may be a potential health hazard from oral exposure to chromium in heavily contaminated sites. Therefore, more extensive research should be conducted to determine if thes findings can be extended to environmentally relevant concentrations.


Assuntos
Carcinógenos Ambientais/farmacocinética , Compostos de Cromo/farmacocinética , Cromo/farmacocinética , Suco Gástrico/química , Poluentes do Solo/análise , Solo/análise , Silicatos de Alumínio/análise , Argila , Dióxido de Silício/análise , Temperatura
6.
Stomatol DDR ; 40(5): 214-6, 1990 May.
Artigo em Alemão | MEDLINE | ID: mdl-2270579

RESUMO

Within an 8-years-longitudinal study 40 patients with 30 tangential and 28 open bridges were examined. The accumulation of plaque as well as the degree of inflammation of the gingiva adjacent to the bridgework binder and the bridgework bodies were determined by means of selected indices, and the data obtained were compared to those evaluated when the bridges were fitted in. The results show that the accumulation of plaque (on) with open bridge was slightly elevated as compared to tangential bridges whereas the inflammation of the gingiva was significantly increased with tangentially shaped bridgework bodies. For this reason open bridges should be used further more in areas, where aesthetics play only a secondary role.


Assuntos
Placa Dentária/prevenção & controle , Planejamento de Dentadura , Prótese Parcial Fixa/efeitos adversos , Gengivite/prevenção & controle , Estomatite sob Prótese/prevenção & controle , Distribuição de Qui-Quadrado , Humanos , Mucosa Bucal
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