Imen Saadaoui

Qatar University · Centre for Sustainable Development

This study was carried out to investigate the impacts of cyanobacteria (Roholtiella sp.) high-value product extract (HVPE) and water resuspended biomass WRB treatments on bell pepper production using the hydroponic system under greenhouse conditions. Six cyanobacteria treatments (6 ml L−1, 4 ml L−1, and 2 ml L−1 – HVPE, 6 ml L−1, 4 ml L−1, and 2 ml...

The purpose of this study is to develop an initial computational model to evaluate the techno-economic viability of high-value and secondary resources from microalgae. The isolation of high-value metabolites is the driving product to improve the overall economics. This approach will allow marketing secondary compounds at more competitive rates for...

The increase in the human population causes an increase in the demand for nutritional supplies and energy resources. Thus, the novel, natural, and renewable resources became of great interest. Here comes the optimistic role of bioprospecting as a promising tool to isolate novel and interesting molecules and microorganisms from the marine environmen...

Four indigenous cyanobacteria isolates identified as QUCCCM 34 Chroococcidiopsis sp, QUCCCM 54 Pleurocapsa sp, QUCCCM 77: Euhalothece sp and QUCCCM 129 Cyanobacterium sp. were investigated during this study. Temperatures and salinities observed in outdoor were reproduced indoor, using small-scale photobioreactors, and culture conditions were optimi...

Rapid drying, cost-effective and safe, will increase the viability of using microalgae for several bio-industrial applications. In this study, five different drying techniques of microalgal biomass were investigated. These include freeze-drying, oven drying, air drying, sun drying, and microwave drying. Morphology, metabolite content, FAME profilin...

Salinity is one of the abiotic stresses that affect crop growth and productivity in arid and semi-arid regions. Unfortunately, there are few known methods to mitigate the deleterious impacts of salt stress on the development and yield of vegetable crops. Blue-green algae (cyanobacteria) are endowed with the potential to curb the negative impacts of...

Oxide nanoparticles are among the most used nanomaterials and have received considerable attention over their potential ecological effects. Increasing investigations report toxicity of certain oxide nanoparticles, however, there are also studies showing opposite results, highlighting the fact that these nanoparticles may differ in their toxicologic...

Demographic explosion, climate change, urbanization, change of life quality, and food demand have put extra pressure on Food, Energy, Water, and Waste (FEWW) resources.A special focus has been placed on university campuses as they are representative urban communities with a substantial need for food, energy, and water and they generate waste. Furth...

Cyanobacteria are found to be renewable and sustainable additives for growth improvement in crops. Extracts and biomass of three nitrogen-fixing cyanobacteria namely, Roholtiella sp. (QUCCCM97), Nostoc ellipsosporum (QUCCCM99), and Desmonostoc danxiaense (QUCCCM112) isolated from Qatar desert environment were tested for their ability to enhance the...

Microalgae are photoautotrophic organisms with high commercial potential. Extracts from microalgae are extensively used in crop cultivation, mainly because they possess growth-promoting properties, coupled with their enhancing impacts on the crop’s ability to withstand abiotic stresses viz. extreme temperatures, drought, salinity, and mineral defic...

There is an immediate need to identify alternative sources of high-nutrient feedstocks for domestic livestock production and poultry, not only to support growing food demands but also to produce microalgae-source functional foods with multiple health benefits. Various species of microalgae and cyanobacteria are used to supplement existing feedstock...

The Arabian Gulf is one of the most adversely affected marine environments worldwide, which results from combined pollution drivers including climate change, oil and gas activities, and coastal anthropogenic disturbances. Desalination activities are one of the major marine pollution drivers regionally and internationally. Arabian Gulf countries rep...

The circular economy concept can enhance sustainability through restructuring consumption and production patterns using innovative designs and business models. This core premise is highly relevant for the interlinked water and food supply sectors in arid regions, which are threatened by natural scarcity and resource overuse. This paper transfers th...

Date palm (Phoenix dactylifera L.) is the main fruit crop found in the arid and semi-arid regions of the world. It naturally adapts to the adverse environments of extreme heat and water scarcity and prevents further desertification in addition to producing fruits with high nutritional value. It is seen in many parts of the world that traditional cu...

Urban communities are affected by population growth, urbanization and climate change, thus being vulnerable to food, energy and water demand. According to the United Nations, the world’s population is expected to increase by 2 billion people in the next 30 years and 68% of them are projected to live in urban areas by then. At the same time, 1/3 of...

Microalgae are believed to be a promising source of different high value products (HVP). HVP are metabolites which are produced during the growth of microalgae and their production is triggered by the physiochemical growth conditions of the microalgae. The present project is aimed at exploring the presence of bioactive compounds in desert microalga...

Aquaculture is considered as a promising alternative to support the food demands of the everincreasing population. Currently, this sector faces several challenges such as using fishmeal, which is unsustainable and expensive. Therefore, it is necessary to identify an alternative feed component that is sustainable, cost-effective and can provide the...

Recently, algae have received considerable interest as one of the most promising feedstocks suitable for animal feed production due to their fast growth, less nutrient requirements and their ability to produce primary and secondary metabolites with high-added value. Different strategies were applied to improve both biomass and metabolites productiv...

Microalgae isolated from the Qatari desert was identified as thermotolerant, with a rich metabolite profile that is appropriate for use as food and health supplements. In this research, a species of Chlorella, QUCCCM3, from the Qatar University Culture Collection of Cyanobacteria and Microalgae, was investigated for its growth characteristics and m...

Lung cancer is one of the major causes of death worldwide. Natural molecules with anti-lung cancer potential are of a great interest and considered as very promising alternative to substitute or enhance the efficiency of the conventional drugs. Recently, algae as source of high value-added compounds are considered as very promising source of these...

Nannochloris atomus (QUCCCM31) is a local marine microalga showing potential to serve as renewable feedstock for biodiesel production. The investigation of the impact of temperature variation and nitrogen concentrations on the biomass and lipid productivities evidenced that biomass productivity increased with the temperature to reach an optimum of...

CO2 fixation by phototrophic microalgae and cyanobacteria is seen as a possible global carbon emissions reducer; however, novel microalgae and cyanobacterial strains with tolerance to elevated temperatures and CO2 concentrations are essential for further development of algae-based carbon capture. Four novel strains isolated from the Arabian Gulf we...

During the last years, several applications of biosurfactants with medical purposes have been reported. Biosurfactants are considered relevant molecules for applications in combating many diseases. However, their use is currently extremely limited due to their high cost in relation to that of chemical surfactants. Use of inexpensive substrates can...

Date palm (Phoenix dactylifera L.) is the main fruit crop found in the arid and semi-arid regions of the world. It naturally adapts to the adverse environments of extreme heat and water scarcity and prevents further desertification in addition to producing fruits with high nutritional value. It is seen in many parts of the world that traditional cu...

Microalgae are considered a very promising alternative for biofuel production. Several strategies were developed to modulate and improve algae metabolites production to meet the requirements for biodiesel production. Most previous research evidenced that the increase of the lipid content is accompanied by a decrease of the biomass production, which...

CO2 fixation by phototrophic microalgae and cyanobacteria is seen as a possible global carbon emissions reducer, which could also be applied to produce useful products. In Qatar, the prospect of using microalgae is very promising: high solar irradiance, large areas of non-arable land, and large amounts of CO2 sources make it an ideal place for alga...

The worldwide continuous increasing of population provokes an increasing awareness about the food security. Qatar is one of the first countries establishing a Food Security Strategy Program to satisfy the demand of food and feed. Microalgae is considered as one of the most promising solution based on its ability to produce the essential elements ne...

CO2 fixation by phototrophic microalgae has been addressed as a possible global carbon emissions reducer, whilst simultaneously producing useful products. Especially in Qatar, the prospect of using microalgae for CO2 abatement is promising: high solar irradiance, large areas of non-arable land, and large amounts of CO2 emissions make it seemingly t...

Microalgae are photosynthetic microorganisms that can grow in different environments (sea water, fresh water, waste water soil, rocks….) and under various conditions (Light, pH, temperature, salinity….). During their phases of growth, they produce a variety of metabolites such as lipids, proteins and carbohydrates in large amounts over a short peri...

The Qatar University Culture Collection of Cyanobacteria and Microalgae (QUCCCM) is a unique resource containing a diverse collection of microalgae and cyanobacteria, isolated from the Qatar desert environment. In order to ensure maximum preservation of this resource, a number of cryopreservation techniques were applied to various strains, and the...

The isolation of autochthonous microalgae, with high lipid-contents and biomass productivities is a crucial aspect of the development of commercial production of microalgae-based biodiesel as well as food security in land-locked locales. This is especially important for deployments in climates such as are found in Qatar, a peninsula in the west Ara...

Algae-derived products, in particular biodiesel, have received increased interest over recent years due to their advantages over fossil fuel derived products. The ability of algae to grow in different qualities of water, with high areal biomass productivities, and photoautotrophic capacity using sunlight and CO 2 as a source of energy, are just of...

Microalgae are photosynthetic microorganisms that can grow in different environments (sea water, fresh water, waste water soil, rocks…) and under various conditions (Light, pH, temperature, salinity…). During their phases of growth, they produce a variety of metabolites such as lipids, proteins and carbohydrates in large amounts over a short period...

Micro algae are a diverse group of aquatic, photosynthetic organisms which are the primary food source for many crustaceans, molluscs and fish species occurring naturally in the marine food chain. In the recent past, micro algae have shown great importance as food supplements not just for the marine Eco system but for the cattle - poultry feed stoc...

A major consequence of the sustained degradation of the coastal environment is the progressive eutrophication, which makes Harmful Algal Blooms (e.g. cyanobacteria) more likely to happen and with potential production of cyanotoxins which may create health hazards. Qatar concerns have been rising following the observations of blooms in the last year...

The vip3Aa16 gene of Bacillus thuringiensis strain BUPM95 was cloned and expressed in Escherichia coli. Optimization of Vip3A16 protein expression was conducted using Plackett-Burman design and response surface methodology. Accordingly, the optimum Vip3A16 toxin production was 170 μg/ml at 18 h post-induction time and 39°C post-induction temperatur...

Bacillus thuringiensis subsp. aizawai strain HD133, known by its effectiveness against Spodoptera species, produces many insecticidal proteins including Cry1Ab, Cry1Ca and Cry1Da. In the present study, the insecticidal activity of Cry1Da against Spodoptera littoralis was investigated. It showed toxicity with an LC(50) of 224.4 ng/cm(2) with 95% con...

During the last years, several applications of biosurfactants with medical purposes have been reported. Biosurfactants are considered relevant molecules for applications in combating many diseases. However, their use is currently extremely limited due to their high cost in relation to that of chemical surfactants. Use of inexpensive substrates can...

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...

A new cry1Ac-type gene was cloned from Bacillus thuringiensis strain BLB1, sequenced and expressed. The deduced amino acid sequence of the polypeptide has a predicted molecular mass of 132.186 kDa. The amino acid sequence alignment of BLB1 Cry1Ac with those of the published ones showed that this is a new delta-endotoxin. When compared with Cry1Ac o...

BLB1 is a new Bacillus thuringiensis kurstaki strain, isolated from a Tunisian soil sample. Assay of toxicity of BLB1 crystal proteins resulted in an LC50 of 70.32 ng of toxin per mg of flour against third instar Ephestia kuehniella with confidence limits of (31.6-109.04 ng). This LC50 is less than that of the commercial strains HD1 used as a refer...

BUPM4 is a Bacillus thuringiensis subsp. kurstaki strain, isolated from Tunisian soil, producing an original bacteriocin named Bacthuricin F4. The optimization of the latter production conditions was carried out under several physicochemical conditions. It was found that the highest bacteriocin activity was reached at low aeration while bacteriocin...

Considering the fact that Prays oleae is one of the most pathogenic insects to the olive tree in the Mediterranean basin, particularly in Tunisia, the mode of action of Cry insecticidal toxins of Bacillus thuringiensis kurstaki in Prays oleae midgut was investigated. The proteolysis of Bacillus thuringiensis delta-endotoxins in the midgut was a key...

gyrB DNA fragments of seven Bacillus thuringiensis local collection family representatives were amplified by PCR and sequenced. Several differences in their corresponding sequences were evidenced. Both in silico and in vitro restriction maps of gyrB sequences and fragments respectively confirmed that EcoRI and Sau3AI could be used to differentiate...