Roda Al-Thani

Qatar University

Bacillus thuringiensis subsp. israelensis (Bti) spherical parasporal crystal contains several insecticidal proteins used as environmentally safe alternative to toxic chemical pesticides. The exploration of a Bti strain isolated from Qatar QBT220 genes encoding the δ-endotoxins responsible of the insecticidal activities revealed the alteration of a...

Fungal infection and synthesis of mycotoxins in coffee leads to significant economic losses. This study aimed to investigate the prevalence of toxigenic fungi, their metabolites, and the effect of traditional roasting and brewing on ochratoxin A (OTA) and aflatoxins (AFs) contents of naturally contaminated coffee samples. In addition, in vivo bioco...

Like other agricultural crops, fungal infection and synthesis of mycotoxins in coffee leads to significant economic losses. This study is aimed at investigating the prevalence of toxigenic fungi, their metabolites, and the effect of traditional roasting and brewing on ochratoxin A (OTA) and aflatoxins (AFs) contents of naturally contaminated coffee...

The Arabian Gulf ranks among the world’s most arid and warm regions; the land has high salinity levels with many Sabkhas and receives little precipitation. This region holds about one-third of the world’s oil supply. Qatar is the leading gas producer worldwide, which raises many concerns about the pollution of the sea, groundwater, and soil. Thus,...

Along with Aspergillus and Penicillium spp., mycotoxins produced by Fusarium species are important contaminants in food and feed industry. This study was designed to investigate the biodegradation potential of a collection of Bacillus spp. in different substrates artificially contaminated with single or multiple Fusarium mycotoxins. B. megaterium B...

Mycotoxins, the metabolites of toxigenic fungi are important contaminants of food and agriculture industry throughout the world. Among the different strategies to minimize the mycotoxins synthesis and decontamination of food; yeasts and their derivatives are used as efficient biological control agents. In this study, cell walls (CW) of six yeast st...

Anthropogenic and industrial wastewater (IWW) could be an additional future source of water to support the needs of the people of the State of Qatar. New lagoons have been built using modern technologies to optimize water use and waste recycling, as well as increasing the green spaces around the country. To achieve successful development of these n...

This research was conducted to investigate the dynamics of airborne fungi using viable culture collection and in respect to different abiotic variables, including seasonal and intra-diurnal variations. A gravimetric method was used to sample airborne fungal deposition on potato dextrose agar plates on alternate days, for a year between April 2015 t...

Mycotoxins are secondary metabolites synthesized by mycotoxigenic fungi belonging mainly to three major fungal genera that are Aspergillus, Fusarium and Penicillium. The latter mycotoxigenic fungi contaminate plants and different food commodities and cause various health concerns (carcinogenicity, mutagenicity, nephrotoxicity, etc...) due to their...

To overcome the economic losses associated with fungi and their toxic metabolites, environmentally safe and efficient approaches are needed. To this end, biological control using yeasts and safe bacterial strains and their products are being explored to replace synthetic fungicides. In the present study, the biocontrol effect of a yeast strain of K...

This study was designed to investigate the antifungal activity of Bacillus pumilus 344-3 against toxigenic fungi. In vitro co-incubation assay revealed that A. carbonarius AC82, A. niger AN8 and P. digitatum PD43 are most sensitive fungi to bacterial antifungal compounds with zone of inhibition of 29.2 mm, 27.7 mm and 27.1 mm, respectively. The add...

Because pollution is predicted to worsen and sources of quality water for agriculture and other human activities are limited, many countries have been motivated to seek novel water sources. Qatar relies on groundwater and water desalinization to meet its water needs, and additional water resources will be needed to avoid unexpected crises in the fu...

Background and aim: Post-harvest fungal infection of fruits and vegetables is mainly caused by fungal pathogens that can be harmful to both human and animals as they produce mycotoxins, post-harvest diseases in fruits and vegetables are a serious problem that results in the loss of a large percentage of crops reaching 50% in some fruits. This stud...

The present study was designed to investigate the antagonistic activity of Bacillus licheniformis BL350-2 against mycotoxigenic strains of Aspergillus and Penicillium. In vitro coincubation for 5 days indicated Aspergillus westerdijkiae BA1 as the most sensitive strain, with a growth inhibition of 62%, followed by A. carbonarius MG7 (60%), Penicill...

This study aimed to explore the incidence of Fusarium fungi and their mycotoxins in marketed feed in Qatar. Samples of mixed-grain-cereal, maize, wheat, millet, barley, oat and soybean were tested for the presence of zearalenone (ZEN), fumonisins, T2/HT2 and deoxynevalenol (DON)mycotoxins. PCR-based identification of the Fusarium isolates was follo...

This study was designed to explore the incidence of aflatoxin M1 (AFM1) in milk and dairy products marketed in Qatar. Milk (n = 72), yogurt (n = 21), cheese (n = 46), butter (n = 18) and laban (n = 25) samples were initially screened by competitive enzyme linked immunosorbent assay (ELISA) for the presence of AFM1, followed by confirmation with ult...

Bacillus thuringiensis (Bt) based insecticidal formulations have been recognized as one of the most successful, environmentally safe and sustainable method of controlling insect pests. Research teams worldwide are in search of Bt diversity giving more choices of bio-insecticides and alternatives to address insect resistance. In fact, there are many...

Cyt1A protein is a cytolytic protein encoded by thecytgene ofBacillus thuringiensissubsp.israelensis(Bti) as part of the parasporal crystal proteins produced during the sporulation. Cyt1A protein is unique compared to the other endotoxins present in these parasporal crystals. Unlike δ-endotoxins, Cyt1A protein does not require receptors to bind to...

The present study was conducted to explore the occurrence of mycotoxins in commercial baby foods in Doha-Qatar. LCMS/MS- and HPLC-based analysis of baby food (n=67) for 12 mycotoxins, confirmed the presence of aflatoxin M1 (AFM1, 33%), ochratoxin A (OTA, 31%), deoxynivalenol (DON, 27%), aflatoxin B1 (AFB1, 22%), fumonisin B2 (FB2, 10%), zearalenone...

Several studies have investigated the biology of native plants (halophytes and xerophytes), biological soil crusts (BSC), as well as the associated and adjacent microorganisms. These studies concentrated on their eco-physiological aspects as well as the possible roles they might play in various life activities and industries. This article presents...

The present study was designed to investigate the occurrence of mycotoxins and toxigenic mycobiota in cereals used as animal feed in a Qatari market. Aflatoxins (AFs) and ochratoxin A (OTA) were detected in 94 and 44% of mixed cereals, 70 and 40% of maize, 40 and 60% of wheat and wheat bran samples, respectively. Among these positive samples, 20 an...

Introduction: Patulin has raised the international attention because of its health risk. In fact, it has mutagenic, neurotoxic, immunotoxic, genotoxic and gastrointestinal effects in animals. In the present work, patulin and patulin-producing Penicillium spp. in apple and apple-based products marketed in Qatar were analysed. Methodology: Samplin...

Graphene based materials have wide potential applications in biology, biomedical, agriculture environmental and biotechnology. Graphene Oxide (GO) is one of those materials and has a promising substance as antimicrobial agents. GO in this study was prepared by a modified Hummers method and was characterized by different techniques for confirmation...

: The Arabian Gulf is an extremely inhospitable and physiologically-stressful environment for marine organisms since they are exposed to the widest range and the highest sea temperatures in the world, as well as high salinities. The present paper assembles and, as far as is possible without extended herbarium study, critically examines the status o...

The Um Alhool area in Qatar is a dynamic evaporative ecosystem that receives seawater from below as it is surrounded by sand dunes. We investigated the chemical composition, the microbial activity and biodiversity of the four main layers (L1-L4) in the photosynthetic mats. Chlorophyll a (Chl a) concentration and distribution (measured by HPLC and h...

Fourteen spice samples were collected from local markets in Doha, Qatar, during 2012, and were surveyed for the presence of potentially harmful mycoflora and for contamination with aflatoxins B1, B2, G1, and G2 by high-performance liquid chromatography (HPLC). Among the tested spice samples, chili powder showed the highest presence of fungal propag...

Microbial mats are only present under extreme conditions, where grazing by higher organisms is limited. Therefore, microbial mats may provide insight into extraterrestrial life, due to their adaptations to extreme temperatures, desiccation or salinity. They are faced with a diurnal cycle with variable length based on their location, which exposes t...

The mineralization of organic matter in marine sediments by microbial activity was studied in Umm Alhool sabkha. In intertidal surface sediments, the development of steep compositional and physico-chemical gradients was a common phenomenon. Rapidly, oxygen is consumed within the upper few mm of marine mats and sediments. In permeable sediments, how...

Global warming, the global carbon cycle, and current and future global trading in carbon credits (the carbon market), are beginning to dictate radical changes in human behaviour. In this context, the cyanobacteria figure prominently. Why? First, vast populations of ancient cyanobacteria and other microalgae are credited with the formation of Earth’...

The desert regions of North and central Qatar were surveyed for lichens. Twelve species were reported. The most common lichens are of the crustose type and all fungi of the lichens collected are Ascomycete.

The desert regions of North and central Qatar were surveyed for lichens. Twelve species were reported. The most common lichens are of the crustose type and all fungi of the lichens collected are Ascomycete.

The aim of this study was to determine the sequence of the 16S rRNA gene and thus to conduct the phylogenic position of the naturally occurring wild type strain of Streptomyces QU66C. Here we show conclusively the full sequence of the 16S rRNA gene of a novel wide type strain of Streptomyces coelicolor which has been isolated from the soil of Qatar...

The study of 257 crystal-producing Bacillus thuringiensis isolates from bioinsecticide free soil samples collected from different sites in Tunisia, was performed by PCR amplification, using six primer pairs specific for cry1, cry2, cry3, cry4, and vip3A genes, by the investigation of strain plasmid pattern, crystal morphology and delta-endotoxin co...

Fourteen macrofungal genera belonging to 11 families and 7 orders were identified. These were isolated from different habitats (semi- desert, gardens, park, decayed roots of dead trees and under trees) in Qatar. Macrofungi are defined here as ascomycetes and basidiomycetes with large, conspicuous spore-bearing structures that form above or beneath...

Fourteen macrofungal genera belonging to 11 families and 7 orders were identified. These were isolated from different habitats (semi- desert, gardens, park, decayed roots of dead trees and under trees) in Qatar. Macrofungi are defined here as ascomycetes and basidiomycetes with large, conspicuous spore-bearing structures that form above or beneath...

Polycyclic aromatic hydrocarbon (PAH)-degrading bacteria were isolated from contaminated soil samples collected from the industrial zone at Umm-Saied city, state of Qatar. Isolation was occurred by enrichment using naphthalene, phenanthrene or anthracene as the sole source of carbon and energy. The isolates were characterized using a variety of phe...

Sabkhat are widely distributed throughout the Qatar Peninsula, and the aim of this study is to give a brief overview of their geographical distribution, geomorphology factors influencing their formation and biological characteristics within the area, with particular reference to their microorganisms. Although there are a large number of individual...

Compared with conventional synthetic flocculants, bioflocculants has special advantages such as safety, strong effect, biodegradable and harmlessness to humans and the environment, so they may potentially be applied in drinking and wastewater treatment, downstream processing, and fermentation processes. To utilize bioflocculants widely in industria...

Pure cultures of 2-chlorophenol degrading bacteria were isolated from a natural enrichment that may be adapted to chlorophenols in the industrial zone at Umm-Saied city (Qatar). The bacteria were identified by 16S rDNA analysis, using PCR with universal primers. Comparative analysis of the 16S rDNA sequence (~ 550 bp) in the GenBank database reveal...

Plant life and the life they support are being eliminated and cannot cope with the construction activities in Doha City. One of the most important reasons behind this study is the fast rate at which many habitats are disappearing due to the higher activities in the construction sites throughout Doha City. These activities are not accompanied by any...

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