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1.
Braz J Biol ; 83: e273643, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37729315

RESUMEN

Recently exposure of olive trees to many stresses particularly oil varieties led to decline in the olive yield. The target of the study is to improve vegetative growth and increase olive fruits quality as well as the fruit oil % and oil quality by applying chitosan nanoparticles (CHNPs) and N-acetyl thiazolidine 4-carboxylic acid (N-ATCA) under the conditions of Egypt. The experiment was carried out in the seasons of 2021 and 2022 on Arbosana olive trees 8 years old and 4×6 m apart the trees sprayed three times on 15th Sept., 1st Oct. and 15th Oct. with (CHNPs at 500, 1000 and 1500 ppm), (N-ATCA at 50, 100 and 150 ppm) and a combination between them and evaluate the vegetative growth of trees, fruit physiochemical characteristics, and oil properties during both study seasons. The application of CHNPs and N-ATCA and a combination of them led to increasing leaf area, total chlorophyll and proline content also increment fruit weight, flesh weight, oil color and oil % moreover improving the quality of produced oil. The improvement in growth, fruit quality, oil % and oil quality, were associated with increasing concentrations of CHNPs, N-ATCA and a combination of them especially (CHNPs at 1500 ppm + N-ATCA at 100 ppm and CHNPs at 1500 ppm + N-ATCA at 150 ppm). Spraying (CHNPs at 1500 ppm + N-ATCA at 150 ppm) is recommended to improve the tree growth, fruit quality, oil % and quality of Arbosana olive.


Asunto(s)
Quitosano , Nanopartículas , Olea , Frutas , Tiazolidinas , Árboles , Ácidos Carboxílicos
2.
Braz. j. biol ; 83: e273643, 2023. tab, graf
Artículo en Inglés | LILACS-Express | VETINDEX | ID: biblio-1513842

RESUMEN

Abstract Recently exposure of olive trees to many stresses particularly oil varieties led to decline in the olive yield. The target of the study is to improve vegetative growth and increase olive fruits quality as well as the fruit oil % and oil quality by applying chitosan nanoparticles (CHNPs) and N-acetyl thiazolidine 4-carboxylic acid (N-ATCA) under the conditions of Egypt. The experiment was carried out in the seasons of 2021 and 2022 on Arbosana olive trees 8 years old and 4×6 m apart the trees sprayed three times on 15th Sept., 1st Oct. and 15th Oct. with (CHNPs at 500, 1000 and 1500 ppm), (N-ATCA at 50, 100 and 150 ppm) and a combination between them and evaluate the vegetative growth of trees, fruit physiochemical characteristics, and oil properties during both study seasons. The application of CHNPs and N-ATCA and a combination of them led to increasing leaf area, total chlorophyll and proline content also increment fruit weight, flesh weight, oil color and oil % moreover improving the quality of produced oil. The improvement in growth, fruit quality, oil % and oil quality, were associated with increasing concentrations of CHNPs, N-ATCA and a combination of them especially (CHNPs at 1500 ppm + N-ATCA at 100 ppm and CHNPs at 1500 ppm + N-ATCA at 150 ppm). Spraying (CHNPs at 1500 ppm + N-ATCA at 150 ppm) is recommended to improve the tree growth, fruit quality, oil % and quality of Arbosana olive.


Resumo Recentemente, a exposição das oliveiras a muitos estresses, particularmente as variedades de azeite, levou ao declínio no rendimento da azeitona. O objetivo do estudo é melhorar o crescimento vegetativo e aumentar a qualidade dos frutos de oliveira, bem como a % de óleo do fruto e a qualidade do óleo, aplicando nanopartículas de quitosana (CHNPs) e ácido N-acetil tiazolidina 4-carboxílico (N-ATCA) nas condições do Egito. O experimento foi realizado nas temporadas de 2021 e 2022 em oliveiras Arbosana de 8 anos e 4×6 m de distância das árvores pulverizadas três vezes em 15 de setembro, 1º de outubro e 15 de outubro com (CHNPs a 500, 1000 e 1500 ppm), (N-ATCA a 50, 100 e 150 ppm) e uma combinação entre eles e avaliar o crescimento vegetativo das árvores, características físico-químicas dos frutos e propriedades do óleo durante as duas épocas de estudo. A aplicação de CHNPs e N-ATCA e uma combinação deles levou ao aumento da área foliar, teor de clorofila total e prolina, além de incrementar o peso do fruto, peso da polpa, cor do óleo e % de óleo, e melhorou a qualidade do óleo produzido. A melhora no crescimento vegetativo, qualidade da fruta, % de óleo e qualidade do óleo foram associados com concentrações crescentes de CHNPs e N-ATCA e uma combinação deles em especial (CHNPs a 1500 ppm + N-ATCA a 100 ppm e CHNPs a 1500 ppm + N-ATCA a 150 ppm). A pulverização (CHNPs a 1500 ppm + N-ATCA a 150 ppm) é recomendada para melhorar o crescimento das árvores, qualidade dos frutos, % de óleo e qualidade da azeitona Arbosana.

3.
J Appl Microbiol ; 128(2): 438-457, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31650655

RESUMEN

AIMS: Investigate the capability of Aspergillus brasiliensis ATCC 16404 to mycosynthesize Co3 O4 -NPs. METHODS AND RESULTS: Mycelial cell-free filtrate of A. brasiliensis ATCC 16404 was applied for mycosynthesis of Co3 O4 -NPs. The preliminary indication for the formation of Co3 O4 -NPs was the change in colour from yellow to reddish-brown. One-factor-at a time-optimization technique was applied to determine the optimum physicochemical conditions required for the mycosynthesis of Co3 O4 -NPs and they were found to be: 72 h for reaction time, pH 11, 30°C, 100 rev min-1 for shaking speed in the darkness using 4 mmol l-1 of CoSO4. 7H2 O and 5·5% of A. brasiliensis dry weight mycelium (w/v). The mycosynthesized Co3 O4 -NPs were characterized using various techniques: spectroscopy including UV/Vis spectrophotometry, dynamic light scattering (DLS), zeta potential measurement, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy and X-ray diffraction; and vibrating sample magnetometry and microscopy including field emission scanning electron microscopy and high-resolution transmission electron microscopy. Spectroscopic techniques confirmed the formation of Co3 O4 -NPs and the microscopic ones confirmed the shape and size of the mycosynthesized Co3 O4 -NPs as quasi-spherical shaped, monodispersed nanoparticles with a nano size range of 20-27 nm. The mycosynthesized Co3 O4 -NPs have excellent magnetic properties and exhibited a good antimicrobial activity against some pathogenic micro-organisms. CONCLUSION: Ferromagnetic Co3 O4 -NPs with considerable antimicrobial activity were for the first time mycosynthesized. SIGNIFICANCE AND IMPACT OF THE STUDY: The use of fungi as potential bionanofactories for mycosynthesis of nanoparticles is relatively a recent field of research with considerable prospects.


Asunto(s)
Antifúngicos/química , Antifúngicos/farmacología , Aspergillus/efectos de los fármacos , Cobalto/química , Cobalto/farmacología , Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Óxidos/química , Óxidos/farmacología , Antifúngicos/síntesis química , Aspergillus/crecimiento & desarrollo , Magnetismo , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
4.
Rev. argent. microbiol ; Rev. argent. microbiol;51(1): 39-46, mar. 2019. ilus
Artículo en Inglés | LILACS | ID: biblio-1003279

RESUMEN

Tributyltin (TBT) is recognized as a major environmental problem at a global scale. Haloalkaliphilic tributyltin (TBT)-degrading bacteria may be a key factor in the remediation of TBT polluted sites. In this work, three haloalkaliphilic bacteria strains were isolated from a TBT-contaminated site in the Mediterranean Sea. After analysis of the 16S rRNA gene sequences the isolates were identified as Sphingobium sp. HS1, Stenotrophomonas chelatiphaga HS2 and Rhizobium borbori HS5. The optimal growth conditions for biodegradation of TBT by the three strains were pH 9 and 7% (w/v) salt concentration. S. chelatiphaga HS2 was the most effective TBT degrader and has the ability to transform most TBT into dibutyltin and monobutyltin (DBT and MBT). A gene was amplified from strain HS2 and identified as TBTB-permease-like, that encodes an ArsB-permease. A reverse transcription polymerase chain reaction analysis in the HS2 strain confirmed that the TBTB-permease-like gene contributes to TBT resistance. The three novel haloalkaliphilic TBT degraders have never been reported previously.


Se considera a la tributiltina (TBT) como un problema medioambiental serio a escala global. Las bacterias haloalcalifílicas degradadoras de TBT pueden constituir un factor clave para remediar áreas contaminadas con dicho xenobiótico. En este estudio se aislaron 3 cepas de bacterias haloalcalifílicas procedentes de un sitio contaminado con TBT en el mar Mediterráneo. Tras analizar las secuencias del gen de 16S del ARNr, se identificaron los aislados como Sphingo-bium sp. HS1, Stenotrophomonas chelatiphaga HS2 y Rhizobium borbori HS5. Las condiciones de crecimiento óptimas para la biodegradación de TBT por parte de las 3 cepas fueron pH 9 y 7% (p/v) de concentración de sal. S. chelatiphaga HS2 fue el degradador de TBT más efectivo, con capacidad de transformar la mayor parte de ese compuesto en dibutiltina y monobutiltina (DBT y MBT). Se amplificó un gen de la cepa HS2, que fue identificado como tipo TBTB-permeasa, que codifica para una ArsB permeasa. Un análisis de la cepa HS2 por reacción en cadena de la polimerasa con transcriptasa inversa (RT PCR) confirmó que el gen TBTB-permeasa contribuye a la resistencia al TBT. Estos 3 nuevos degradadores haloalcalifílicos de TBT no habían sido reportados previamente.


Asunto(s)
Bacterias/aislamiento & purificación , Restauración y Remediación Ambiental/métodos , Biodegradación Ambiental , Mar Mediterráneo/epidemiología , Reacción en Cadena de la Polimerasa/métodos , Transcripción Reversa/genética , /análisis
5.
Rev Argent Microbiol ; 51(1): 39-46, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29605458

RESUMEN

Tributyltin (TBT) is recognized as a major environmental problem at a global scale. Haloalkaliphilic tributyltin (TBT)-degrading bacteria may be a key factor in the remediation of TBT polluted sites. In this work, three haloalkaliphilic bacteria strains were isolated from a TBT-contaminated site in the Mediterranean Sea. After analysis of the 16S rRNA gene sequences the isolates were identified as Sphingobium sp. HS1, Stenotrophomonas chelatiphaga HS2 and Rhizobium borbori HS5. The optimal growth conditions for biodegradation of TBT by the three strains were pH 9 and 7% (w/v) salt concentration. S. chelatiphaga HS2 was the most effective TBT degrader and has the ability to transform most TBT into dibutyltin and monobutyltin (DBT and MBT). A gene was amplified from strain HS2 and identified as TBTB-permease-like, that encodes an ArsB-permease. A reverse transcription polymerase chain reaction analysis in the HS2 strain confirmed that the TBTB-permease-like gene contributes to TBT resistance. The three novel haloalkaliphilic TBT degraders have never been reported previously.


Asunto(s)
Bacterias/metabolismo , Compuestos de Trialquiltina/metabolismo , Contaminantes Químicos del Agua/metabolismo , Biodegradación Ambiental , Egipto , Concentración de Iones de Hidrógeno , Mar Mediterráneo , Tolerancia a la Sal
6.
J Appl Microbiol ; 125(2): 370-382, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29624805

RESUMEN

AIMS: Since mycosynthesis of metal nanoparticles (NPs) is advertised as a promising and ecofriendly approach. Thus, this study aims to investigate the capability of Aspergillus brasiliensis ATCC 16404 for mycosynthesis of silver NPs (AgNPs). METHODS AND RESULTS: One-factor-at-a-time-technique was used to study the effect of different physicochemical parameters: the reaction time, pH, temperature, different stirring rates, illumination, and finally, the different concentrations of silver nitrate and fungal biomass on the mycosynthesis of AgNPs. The visual observation showed the characteristic brown colour formation due to the bioreduction of Ag+ ions to Ag0 by the mycelial cell-free filtrate (MCFF). The UV/visible spectrophotometric technique displayed a characteristic sharp peak at ʎ440 confirming the mycosynthesis of AgNPs. The zeta potential value -16·7 mV assured the long-term stability of AgNPs and the dynamic light scattering analysis revealed good dispersion and average particle size 77 nm. The energy dispersive X-ray spectroscopy displayed a maximum elemental distribution of silver elements. The X-ray diffraction spectroscopy demonstrated the crystallinity of the mycosynthesized AgNPs. The field emission scanning electron microscope and high-resolution transmission electron microscope revealed monodispersed spherical shaped AgNPs with average particle size of 6-21 nm. The FTIR analysis showed the major peaks of proteins providing the possible role of MCFF in the synthesis and stabilization of the AgNPs. The mycosynthesized AgNPs expressed good biocidal activity against different pathogenic micro-organisms causing some water-related diseases and health problems to local residents. CONCLUSIONS: This study proved that A. brasiliensis ATCC 16404 MCFF has good potential for mycosynthesis of AgNPs, which exhibited good antimicrobial effect on different pathogenic micro-organisms; thus, it can be applied for water disinfection. SIGNIFICANCE AND IMPACT OF THE STUDY: This research provides a helpful insight into the development of a new mycosynthesized antimicrobial agent.


Asunto(s)
Antibacterianos/farmacología , Aspergillus/metabolismo , Nanopartículas del Metal/química , Plata/farmacología , Antibacterianos/química , Estabilidad de Medicamentos , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Plata/química , Propiedades de Superficie
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