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1.
Mar Drugs ; 16(12)2018 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-30513984

RESUMEN

Fusarium solani H915 is a fungus derived from mangrove sediments. From its ethyl acetate extract, a new alkenoic acid, fusaridioic acid A (1), three new bis-alkenoic acid esters, namely, fusariumester A1 (2), A2 (3) and B (4), together with three known compounds (5⁻7), were isolated. The structures of the new compounds were comprehensively characterized by high resolution electrospray ionization-mass spectrometry (HR-ESI-MS), 1D and 2D nuclear magnetic resonance (NMR). Additionally, the antifungal activities against tea pathogenic fungi Pestalotiopsis theae and Colletotrichum gloeosporioides were studied. The new compound, 4, containing a ß-lactone ring, exhibited moderate inhibitory activity against P. theae, with an MIC of 50 µg/disc. Hymeglusin (6), a typical ß-lactone antibiotic and a terpenoid alkaloid, equisetin (7), exhibited potent inhibitory activities against both fungal species. The isolated compounds were evaluated for their effects on zebrafish embryo development. Equisetin clearly imparted toxic effect on zebrafish even at low concentrations. However, none of the alkenoic acid derivatives exhibited significant toxicity to zebrafish eggs, embryos, or larvae. Thus, the ß-lactone containing alkenoic acid derivatives from F. solani H915 are low in toxicity and are potent antifungal agents against tea pathogenic fungi.


Asunto(s)
Alquenos/farmacología , Antifúngicos/farmacología , Camellia sinensis/microbiología , Fusarium/química , Enfermedades de las Plantas/prevención & control , Alquenos/química , Alquenos/aislamiento & purificación , Animales , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Colletotrichum/efectos de los fármacos , Embrión no Mamífero , Sedimentos Geológicos/microbiología , Pruebas de Sensibilidad Microbiana , Enfermedades de las Plantas/microbiología , Pirrolidinonas/química , Pirrolidinonas/aislamiento & purificación , Pirrolidinonas/farmacología , Espectrometría de Masa por Ionización de Electrospray , Tetrahidronaftalenos/química , Tetrahidronaftalenos/aislamiento & purificación , Tetrahidronaftalenos/farmacología , Pruebas de Toxicidad , Humedales , Pez Cebra
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(3): 823-6, 2014 Mar.
Artículo en Chino | MEDLINE | ID: mdl-25208421

RESUMEN

Four kinds of extracts from the xylem of C. Camphora, ACQ and camphor were selected to make wood preservatives for laboratory toxicity test of wood preservatives for decay fungus. The results showed that the treated blocks with 4% ACQ and 10% methanol extracts could meet the demand of degree I of preservation and showed strong resistance to brown-rot fungus at tack. The wood treated with 4% camphor extracts, 10% ethyl acetate extracts, and 10% acetone extracts reached the demand of degree II and showed moderate decay resistance. The blocks treated with 10% hot water extracts and untreated samples meet the demand of degree III. Through XRD comparison, the author was found that the preservative effects of four extracts are proportional to the degree of crystallinity. Crystallization fields 2 theta diffraction angle were ordered from larger to little as 10% hot wa-ter extracts > untreated samples > 10% acetone extracts > 10% methanol extracts > 1% ethyl acetate extracts. According to FTIR analysis, the amount of degraded cellulose and hemicellulose increased with the decline of characteristic absorption peak at 1,374, 1,160, 1,106, 1,056 and 897 cm(-1), meaning that the preservative effect of corresponding preservatives were getting worse. The peak height of characterization of lignin is higher compared to the untreated wood. I1,510/I1,738, I1,510/I1,374, l51,510/ I1,160 of the treated blocks with 10% methanol extracts and 4% ACQ are the smallest in all the treated blocks, which proved that the degradation ability of brown--rot fungus to the holocellulose is the weakest, and the wood preservative is best.


Asunto(s)
Cinnamomum camphora/química , Madera , Xilema/química , Celulosa , Hongos , Lignina , Polisacáridos , Espectroscopía Infrarroja por Transformada de Fourier
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(5): 1262-5, 2012 May.
Artículo en Chino | MEDLINE | ID: mdl-22827068

RESUMEN

Raman spectroscopy can be used in situ real-time measurement because it's rapid, and it is helpful to real-time online monitoring of process control. With the complexity of the environment and the characteristics of Raman signal, it is hard to avoid some overlapping spectrum peaks. Based on the advantage of immune algorithm, an immune algorithm (IA) was applied to the overlapping Raman signals of aromatics. With extraction of each single Raman spectrum peak signal from the mixture signals for resolution, Results show that the method is effective to identify the overlapped Raman signal for its fast resolution and accurate quantitative determination with the relative error less than 1%. For the overlapping Raman signals with fluorescence background disturbance, we proposed an adaptive immune algorithm, which is combined with independent component analysis. It can effectively resolve the fluorescence background signal, and it provides a new way for Raman spectra analysis of complex samples.

4.
Chinese Journal of Epidemiology ; (12): 1104-1107, 2003.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-246394

RESUMEN

<p><b>OBJECTIVE</b>To study the prevalence of mild cognitive impairment (MCI) in the urban and the rural areas in Chengdu, Southwest China.</p><p><b>METHODS</b>Residents aged 55 or over were selected by stratified random cluster sampling from 19 districts, cities, and counties of Chengdu area in Sichuan province. A two-stage survey was carried out. In the first stage, CMMSE, CES-D were used as screening instruments. In the second stage, Diagnostic questionnaires of dementia and CDR were used as diagnostic instruments. The diagnostic criteria of mild cognitive impairment adopted from Petersen's were: (1) memory complaint; (2) normal activities of daily living; (3) normal general cognitive function; (4) memory impairment incompatible with age; (5) not demented; (6) CDR = 0.5 and (7) exclusion of the reversible cognitive impairment caused by other factors (i.e. depression).</p><p><b>RESULTS</b>Three thousand, nine hundred and ten subjects were examined. The prevalence rates of MCI was 2.4%. The MCI prevalence rates in the urban and the rural areas were 1.5%, 2.5% respectively, without significant difference. The MCI prevalence in males and females were 1.8%, 2.9% respectively. Prevalence rate in female was higher than in males with significant difference. Prevalence of illiteracy (4.0%) was the highest among different educational levels. The accumulated prevalence increased with age.</p><p><b>CONCLUSION</b>The prevalence of MCI (2.4%) was slightly higher than the prevalence of AD (2.05%) in the same areas of Chengdu. MCI seemed to be a high risk factor for AD which should to be followed up. Early intervention in MCI might be helpful in the prevention of AD.</p>


Asunto(s)
Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Edad , China , Epidemiología , Trastornos del Conocimiento , Epidemiología , Prevalencia , Distribución Aleatoria , Características de la Residencia , Factores de Riesgo , Factores Sexuales , Clase Social
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