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البحوث المنشورة

البحث (1):

عنوان البحث:

Proficiency of biosynthesized silver nanoparticles as a fungicide against selected damping off causing fungi

رابط إلى البحث:

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تاريخ النشر:

  01/07/2015

موجز عن البحث:

The present study aimed at studying the fungicidal properties of nano-sized silver particles (AgNPs), biosynthesized from Nocardiopsis dassonvillei at 10, 20, 40, 80 and 160 μg ml-1 against selected damping off causing fungi. Silver nanoparticles (AgNPs) were characterized by energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). TEM micrographs revealed extracellular formation of spherical nanoparticles with an average size of 25.8 nm. All the tested fungi were highly inhibited by the biosynthesized AgNPs. Its effective concentrations inhibiting 50% of the fungal growth (EC50) values on F. Solani, A. alternate, F. oxysporum and R. solani were 1.25, 3.23, 4.3 and 9.2 μg ml-1, respectively. The present study proved that biosynthesized AgNPs as a promising fungicide against the treated fungi.

المؤتمرات العلمية:

المؤتمر (1):

عنوان المؤتمر:

The 7th Congress of European Microbiologists                  

تاريخ الإنعقاد:

  09/07/2017

مكان الإنعقاد:

Valencia, Spain

طبيعة المشاركة:

Poster presentation

عنوان المشاركة:

Responses of Soil Bacteria Communities to Various Hydrocarbon Contaminants

ملخص المشاركة:

Hydrocarbons contamination of soil is a widespread and urgent environmental problem. Many studies have examined impacts of a single crude or fuel oil on microbial community composition. Other studies have examined effects of one or more polycyclic aromatic hydrocarbons (PAHs), but rarely at the same time as crude or fuel oil. In consequence we do not know which components of oil have the biggest effects on microbial communities in the soil. We compare responses of bacteria communities to a linear alkane (hexadecane), a PAH (fluoranthene) and diesel oil in different soil types, using Illumina sequencing of PCR amplified bacterial 16S sequences supplemented with metagenomics data. There were significant impacts of all hydrocarbons on the communities in both soil types, with fluoranthene having the greatest effect.  The extent to which the responses of communities in the two soils are similar depends upon the taxonomic level at which the comparison is made, helping to explain reports in the literature that different soils show idiosyncratic responses to hydrocarbon contamination. 

المؤتمر (2):

عنوان المؤتمر:

Joint Annual Meeting: Ecology Across Borders      

تاريخ الإنعقاد:

11/12/2017

مكان الإنعقاد:

Ghent, Belgium

طبيعة المشاركة:

Poster presentation

عنوان المشاركة:

Effects of Diesel contamination on bacteria communities in various soil types

ملخص المشاركة:

Diesel contamination of soil is a significant global problem. Microbial community composition changes in response to hydrocarbons, but different soils often show contrasting responses, and it is not known whether these differences are due to the physical and chemical properties of the soil itself, or to initial taxonomic composition. We investigate responses to diesel oil in three different soil types and compare this with responses of the same communities inoculated into (sterile) compost, using Illumina sequencing of PCR amplified bacterial 16S sequences supplemented with metagenomic data. When data are analysed as anonymous OTUs, corresponding approximately to “species”, all three soils are different from each other. All show a response to diesel contamination, but it is difficult to see any overarching pattern.  When phylogenetic relationships between OTUs are taken into account using Unifrac distances, two soils show every similar community composition and similar effects of diesel can be seen on all three. Contamination must act on the taxa that are initially present, and a substantial component of the idiosyncratic responses of different soils to diesel oil contamination is because at a species level everything isn’t everywhere.  The similarity of response that emerges when phylogenetic relationships are accounted for will be entirely invisible in older literature using fingerprinting techniques like ARISA.