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Copyright of Egyptian Journal of Botany is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study was conducted to determine what effects nanoparticles (NPs) like TiO2, ZnO, and Ag may pose on natural attenuation processes of petroleum hydrocarbons in contaminated soils. The solid NPs used were identified using x‐ray diffraction technique and their average size was certified as 18.2, 16.9, and 18.3 nm for Ag‐NPs, ZnO‐NPs, and TiO2‐NPs, respectively. NPs in soil microcosms behave differently where it was dissolved as in case of Ag‐NPs, partially dissolved as in ZnO‐NPs or changed into other crystalline phase as in TiO2‐NPs. In this investigation, catabolic gene encoding catechol 2,3 dioxygenase (C23DO) was selected specifically as biomarker for monitoring hydrocarbon biodegradation potential by measuring its transcripts by RT‐qPCR. TiO2‐NPs amended microcosms showed almost no change in C23DO expression profile or bacterial community which were dominated by Bacillus sp., Mycobacterium sp., Microbacterium sp., Clostridium sp., beside uncultured bacteria, including uncultured proteobacteria, Thauera sp. and Clostridia. XRD pattern suggested that TiO2‐NPs in microcosms were changed into other non‐inhibitory crystalline phase, consequently, showing the maximum degradation profile for most low molecular weight oil fractions and partially for the high molecular weight ones. Increasing ZnO‐NPs concentration in microcosms resulted in a reduction in the expression of C23DO with a concomitant slight deteriorative effect on bacterial populations ending up with elimination of Clostridium sp., Thauera sp., and uncultured proteobacteria. The oil‐degradation efficiency was reduced compared to TiO2‐NPs amended microcosms. In microcosms, Ag‐NPs were not detected in the crystalline form but were available in the ionic form that inhibited most bacterial populations and resulted in a limited degradation profile of oil, specifically the low molecular weight fractions. Ag‐NPs amended microcosms showed a significant reduction (80%) in C23DO gene expression and a detrimental effect on bacterial populations including key players like Mycobacterium sp., Microbacterium sp., and Thauera sp. involved in the biodegradation of petroleum hydrocarbons. [ABSTRACT FROM AUTHOR]

An environmentally-friendly and easy synthesis of a series of novel functionalized imidazolium-based ionic liquids (ILs) is described under both the conventional procedure and microwave irradiation. The structures of newly synthesized room-temperature ionic liquids (RTILs) were established by different spectral analyses. All ILs (1–14) were screened for their in vitro antimicrobial activity against a panel of clinically isolated bacteria. The results of the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) showed that some of the tested ILs are very promising anti-bacterial agents especially those containing an alkyl chain with a phenyl group (most notably 1, 2, 12, and 13). [ABSTRACT FROM AUTHOR]

The washwater from strawberries had the highest level of contamination by fungal species compared to washwater from cherries or red grapes. The fungal counts in the washwater from moldy fruits were much higher than those recovered from healthy fruits. Aspergillus niger and Penicillium italicum were the most dominant fungi isolated from the fruit washwater. Treatment of the washwater with double atmospheric pressure cold plasma (DAPCP) for 7.5 min induced a significant reduction in the colony forming units of fungal species that reached 74.7-100% in the washwater of cherries. The variation in plasma efficacy for the different samples was dependent on the level of antioxidants in the washwater, which attenuated the oxidizing radicals and reduced the life span of the reactive species generated by the plasma, particularly oxygen radicals. Upon DAPCP treatment, the spores of A. niger exhibited electroporation in their walls. The treatment of the washwater with DAPCP for 9 min induced a steady reduction in the amount of mycotoxins in the washwater of moldy fruits, reaching reductions of 87.93, 66.42, and 72.00% for aflatoxins, fumonisins, and ochratoxins, respectively, in the washwater from cherries. [ABSTRACT FROM AUTHOR]

In view of the emerging importance of the ILs as "green" materials with wide applications and our general interests in green processes, a series of a twenty five new 1-alkyl-3-(4-phenoxybutyl) imidazolium-based ionic liquids (ILs) derivatives is synthesized using a facile and green ultrasound-assisted procedure. Their structures were characterized by FT-IR, ¹H-NMR, 13C-NMR, 11B, 19F, 31P, and mass spectrometry. Antimicrobial screens of some selected ILs were conducted against a panel of Gram-positive and Gram-negative bacteria. The antimicrobial activity of each compound was measured by determination of the minimal inhibitory concentration (MIC) yielding very interesting and promising results. Their antibacterial activities are reported, and, on the basis of the experimental and virtual POM screening data available, attempt is also made to elucidate the structure activity relationship. [ABSTRACT FROM AUTHOR]

The aerobic degradation of phenylacetate (PA) by many bacteria has recently been shown to proceed via an unprecedented catabolic route. A typical feature of this pathway is the transformation of PA to phenylacetyl-coenzyme A (PACoA). However, the aerobic degradation of PA by Acinetobacter spp. is not sufficiently understood. To gain insight into the catabolism of PA by Acinetobacter spp., we isolated several PA-degrading Acinetobacter spp. from a wastewater treatment plant in Germany using enrichment cultures with PA as a sole carbon source. We also conducted in vitro PA transformation assays based on the detection of PACoA. The identification of the isolated bacteria was based on partial 16S rDNA sequences. Phylogenetic analysis revealed that the isolated strains are members of the Acinetobacter group and could be regarded as strains of Acinetobacter spp. The soluble protein fraction obtained from cells cultured on PA-containing medium transformed PA to several intermediates, as detected by thin layer chromatography and autoradiography. The formation of one intermediate was CoA dependent and comigrated with a sample of PACoA, the earliest characteristic intermediate of the PA catabolic pathway, suggesting that the isolated PA-degrading Acinetobacter spp. utilize the recently elucidated PA catabolic pathway. A database search revealed that many Acinetobacter spp. harbor PA catabolic genes analogous to the paa gene cluster of Escherichia coli K-12. [ABSTRACT FROM AUTHOR]

Background: Aedes aegypti is the main vector of the yellow fever and dengue virus. This mosquito has become the major indirect cause of morbidity and mortality of the human worldwide. Dengue virus activity has been reported recently in the western areas of Saudi Arabia. There is no vaccine for dengue virus until now, and the control of the disease depends on the control of the vector., Objectives: The present study has aimed to perform phylogenetic analysis of Aedes aegypti based on mitochondrial NADH dehydrogenase subunit 4 ( ND4 ) gene at Almadinah, Saudi Arabia in order to get further insight into the epidemiology and transmission of this vector., Materials and Methods: Mitochondrial ND4 gene was sequenced in the eight isolated Aedes aegypti mosquitoes from Almadinah, Saudi Arabia, sequences were aligned, and phylogenetic analysis were performed and compared with 54 sequences of Aedes reported in the previous studies from Mexico, Thailand, Brazil, and Africa., Results: Our results suggest that increased gene flow among Aedes aegypti populations occurs between Africa and Saudi Arabia., Conclusions: Phylogenetic relationship analysis showed two genetically distinct Aedes aegypti in Saudi Arabia derived from dual African ancestor.