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Temperature and light are two of the most crucial factors for microalgae production. Variations in these factors alter their growth kinetics, macromolecular composition and physiological properties, including cell membrane permeability and fluidity. The variations define the adaptation mechanisms adopted by the microalgae to withstand changes in these environmental factors. In the Qatar desert the temperature varies widely, typically between 10° and 45 °C There are also wide variations in light intensity, with values of over 1500 μmolhν.m−2s−1 in summer. A study of the effects of these thermal and light fluctuations is therefore essential for large-scale outdoor production systems, especially during the summer when temperature and light fluctuations are at their highest. The aim of this work is to study the impact of temperature and light intensity variations as encountered in summer period on the Nannochloropsis QU130 strain, which was selected for its suitability for outdoor cultivation in the harsh conditions of the Qatar desert. It was carried out using lab-scale photobioreactors enabling simulation of both constant and dynamic temperature and light regimes. Biomass productivity, cell morphology and biochemical compositions were examined first in constant conditions, then in typical outdoor cultivation conditions to elucidate the adjustments in cell function in respect of fluctuations. The dynamic light and temperature were shown to have interactive effects. The application of temperature cycles under constant light led to a 13.6% increase in biomass productivity, while a 45% decrease was observed under light and temperature regimes due to the combined stress. In all cases, the results proved that N. sp. QU130 has a high level of adaptation to the wide fluctuations in light and temperature stress. This was shown through its ability to easily change its physiology (cell size) and metabolic process in response to different cultivation conditions.
Hareb Al Jabri; Aumaya Taleb; Raphaelle Touchard; Imen Saadaoui; Vincent Goetz; Jeremy Pruvost. Cultivating Microalgae in Desert Conditions: Evaluation of the Effect of Light-Temperature Summer Conditions on the Growth and Metabolism of Nannochloropsis QU130. Applied Sciences 2021, 11, 3799 .
AMA StyleHareb Al Jabri, Aumaya Taleb, Raphaelle Touchard, Imen Saadaoui, Vincent Goetz, Jeremy Pruvost. Cultivating Microalgae in Desert Conditions: Evaluation of the Effect of Light-Temperature Summer Conditions on the Growth and Metabolism of Nannochloropsis QU130. Applied Sciences. 2021; 11 (9):3799.
Chicago/Turabian StyleHareb Al Jabri; Aumaya Taleb; Raphaelle Touchard; Imen Saadaoui; Vincent Goetz; Jeremy Pruvost. 2021. "Cultivating Microalgae in Desert Conditions: Evaluation of the Effect of Light-Temperature Summer Conditions on the Growth and Metabolism of Nannochloropsis QU130." Applied Sciences 11, no. 9: 3799.
In recent years, Qatar has witnessed exponential growth in the human population, urbanization, and increased anthropogenic activities, including agriculture. Potentially toxic environmental contaminants, including metals and metalloids, are commonly found in emerging economies. At high concentrations, elements such as As, Cr, and Ni can be hazardous and may lead to various health problems in humans, including cancer. The current study measured As, Cd, Cr, Cu, Ni, Pb, V, and Zn concentrations in agricultural soils. Pollution levels and potential negative impacts on human and environmental health were determined using the United States Environmental Protection Agency (USEPA) standard methodologies. According to the study’s findings, the studied element concentrations descended in the following order: Zn > Cr > V > Ni > As > Cu > Pb > Cd. Of these, As (27.6 mg/kg), Cr (85.7 mg/kg), Ni (61.9 mg/kg), and Zn (92.3 mg/kg) concentrations were higher than average world background levels. Each of these elements also had an enrichment factor (EF > 1), indicating their anthropogenic origin. The combined pollution load index (PLI > 1) and geo-accumulation index (Igeo) range values of −0.2–2.5 further indicated that the soil was up to 58% polluted. However, the ecological risk factor (Er ≤ 40.6) and potential ecological risk index (PERI = 79.6) suggested low ecological risk. A human health risk evaluation showed that only As, with a hazard index (HI) of 1.3, posed a noncarcinogenic risk to infants. Additionally, As, Cr, and Ni, with total carcinogenic risk (TCR) values of 1.18 × 10−4 and 2.06 × 10−4 for adults and children, respectively, proved carcinogenic to both age groups. The elements’ carcinogenic risk (CR) potential descended in the following order: Ni > As > Cr. Additionally, for both adults and children, oral ingestion is the most likely exposure pathway. Our findings support the need for closer monitoring of potentially toxic metals and metalloids levels in cultivated soils and farm produce in Qatar. Reducing the elements’ bioavailability in soil and developing innovative remediation technologies is needed to limit potential risks to human health. Further studies on As, Cr, and Ni gastrointestinal bioaccessibilities are needed to fully understand the effects after long-term exposure and the cancer-causing potential of these elements over a lifetime.
Mohammed Alsafran; Kamal Usman; Hareb Al Jabri; Muhammad Rizwan. Ecological and Health Risks Assessment of Potentially Toxic Metals and Metalloids Contaminants: A Case Study of Agricultural Soils in Qatar. Toxics 2021, 9, 35 .
AMA StyleMohammed Alsafran, Kamal Usman, Hareb Al Jabri, Muhammad Rizwan. Ecological and Health Risks Assessment of Potentially Toxic Metals and Metalloids Contaminants: A Case Study of Agricultural Soils in Qatar. Toxics. 2021; 9 (2):35.
Chicago/Turabian StyleMohammed Alsafran; Kamal Usman; Hareb Al Jabri; Muhammad Rizwan. 2021. "Ecological and Health Risks Assessment of Potentially Toxic Metals and Metalloids Contaminants: A Case Study of Agricultural Soils in Qatar." Toxics 9, no. 2: 35.
The treatment of different types of wastewater by physicochemical or biological (non-microalgal) methods could often be either inefficient or energy-intensive. Microalgae are ubiquitous microscopic organisms, which thrive in water bodies that contain the necessary nutrients. Wastewaters are typically contaminated with nitrogen, phosphorus, and other trace elements, which microalgae require for their cell growth. In addition, most of the microalgae are photosynthetic in nature, and these organisms do not require an organic source for their proliferation, although some strains could utilize organics both in the presence and absence of light. Therefore, microalgal bioremediation could be integrated with existing treatment methods or adopted as the single biological method for efficiently treating wastewater. This review paper summarized the mechanisms of pollutants removal by microalgae, microalgal bioremediation potential of different types of wastewaters, the potential application of wastewater-grown microalgal biomass, existing challenges, and the future direction of microalgal application in wastewater treatment.
Hareb Al-Jabri; Probir Das; Shoyeb Khan; Mahmoud Thaher; Mohammed Abdulquadir. Treatment of Wastewaters by Microalgae and the Potential Applications of the Produced Biomass—A Review. Water 2020, 13, 27 .
AMA StyleHareb Al-Jabri, Probir Das, Shoyeb Khan, Mahmoud Thaher, Mohammed Abdulquadir. Treatment of Wastewaters by Microalgae and the Potential Applications of the Produced Biomass—A Review. Water. 2020; 13 (1):27.
Chicago/Turabian StyleHareb Al-Jabri; Probir Das; Shoyeb Khan; Mahmoud Thaher; Mohammed Abdulquadir. 2020. "Treatment of Wastewaters by Microalgae and the Potential Applications of the Produced Biomass—A Review." Water 13, no. 1: 27.
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 metabolite compositions for use as potential feedstock for food production. The strain was cultivated at 30, 35, and 40 °C, covering the annual average low and high temperatures in Qatar. The highest growth rates were recorded for cultures at 30 °C with 0.64 ± 0.04 day−1, followed by a growth rate of 0.54 ± 0.06 day−1 at 40 °C, indicating its thermotolerance ability. The biomass exhibited a high protein content (43 ± 2.3%), with existence of lysine (4.13%) as an essential amino acid, and docosahexaenoic acid, linoleic acid, and alpha-linolenic acid as important omega fatty acids present. On the other hand, Chlorella sp. QUCCCM3 also exhibited a high capacity for scavenging free radicals with an antiproliferative effect against chronic myeloid leukemia K562 cancer cells. The results indicate that Chlorella sp. QUCCCM3 is a promising candidate that can be produced year-round, in the Qatar environment, for commercial applications such as feed and nutraceutical supplements.
Rihab Rasheed; Imen Saadaoui; Touria Bounnit; Maroua Cherif; Ghamza Al Ghazal; Hareb Al Jabri. Sustainable Food Production and Nutraceutical Applications from Qatar Desert Chlorella sp. (Chlorophyceae). Animals 2020, 10, 1413 .
AMA StyleRihab Rasheed, Imen Saadaoui, Touria Bounnit, Maroua Cherif, Ghamza Al Ghazal, Hareb Al Jabri. Sustainable Food Production and Nutraceutical Applications from Qatar Desert Chlorella sp. (Chlorophyceae). Animals. 2020; 10 (8):1413.
Chicago/Turabian StyleRihab Rasheed; Imen Saadaoui; Touria Bounnit; Maroua Cherif; Ghamza Al Ghazal; Hareb Al Jabri. 2020. "Sustainable Food Production and Nutraceutical Applications from Qatar Desert Chlorella sp. (Chlorophyceae)." Animals 10, no. 8: 1413.
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 bioactive molecules. These are secondary metabolites that consist mainly of derivatives of peptides, carbohydrates, and lipids with various structures. Accordingly, various mechanisms by which different algae molecules demonstrate attenuation of tumor angiogenesis were stated and discussed. The mode of action of the algae bioactives is closely related to their nature and chemical structure. Furthermore, this literature review considers the synergistic effect between microalgae bioactives and conventional drugs and discuss the economic feasibility of producing microalgae bioactives at large scale to conclude with some future perspectives related to algae-based drug discovery.
Imen Saadaoui; Rihab Rasheed; Nabeel Abdulrahman; Touria Bounnit; Maroua Cherif; Hareb Al Jabri; Fatima Mraiche. Algae-Derived Bioactive Compounds with Anti-Lung Cancer Potential. Marine Drugs 2020, 18, 197 .
AMA StyleImen Saadaoui, Rihab Rasheed, Nabeel Abdulrahman, Touria Bounnit, Maroua Cherif, Hareb Al Jabri, Fatima Mraiche. Algae-Derived Bioactive Compounds with Anti-Lung Cancer Potential. Marine Drugs. 2020; 18 (4):197.
Chicago/Turabian StyleImen Saadaoui; Rihab Rasheed; Nabeel Abdulrahman; Touria Bounnit; Maroua Cherif; Hareb Al Jabri; Fatima Mraiche. 2020. "Algae-Derived Bioactive Compounds with Anti-Lung Cancer Potential." Marine Drugs 18, no. 4: 197.
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 195 mgL−1 d−1 at 30 °C. Similarly, the lipid content was strongly influenced by the elevation of temperature; indeed, it increased up to ~3 folds when the temperature increased from 20 to 40 °C. When both stresses were combined, triacylglycerols and lipid productivity reached a maximum of 45% and 88 mgL−1 d−1, respectively at 40 °C. Cultures under high temperatures along with Nitrogen-Depleted (ND) favored the synthesis of Fatty Acids Methyl Ester (FAMEs) suitable for high quality biodiesel production, whereas cultures conducted at low temperature coupled with Nitrogen-Limited (NL) led to a production of polyunsaturated fatty acids (PUFAs). Our results support the feasibility of cultivating the thermotolerant isolate QUCCCM31 year-round to meet the sustainability challenges of algal biomass production by growing under temperature and nitrogen variations. The presence of omega 3 and 9 fatty acids as valuable co-products will help in reducing the total process cost via biorefinery.
Touria Bounnit; Imen Saadaoui; Rihab Rasheed; Kira Schipper; Maryam Al Muraikhi; Hareb Al Jabri. Sustainable Production of Nannochloris atomus Biomass Towards Biodiesel Production. Sustainability 2020, 12, 2008 .
AMA StyleTouria Bounnit, Imen Saadaoui, Rihab Rasheed, Kira Schipper, Maryam Al Muraikhi, Hareb Al Jabri. Sustainable Production of Nannochloris atomus Biomass Towards Biodiesel Production. Sustainability. 2020; 12 (5):2008.
Chicago/Turabian StyleTouria Bounnit; Imen Saadaoui; Rihab Rasheed; Kira Schipper; Maryam Al Muraikhi; Hareb Al Jabri. 2020. "Sustainable Production of Nannochloris atomus Biomass Towards Biodiesel Production." Sustainability 12, no. 5: 2008.
Harmful Algal Bloom species are ubiquitous and their blooms occur in the Arabian Gulf. In this study, two cruises were performed in 2012 and 2013 to collect phytoplankton samples from 4 sites in the Arabian Gulf. Toxin analyses of phytoplankton samples for 32 algal toxins from 5 different toxin groups were conducted on the samples using both enzyme linked immunosorbent assay (ELISA) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results demonstrated, for the first time, the presence of paralytic shellfish toxins (PSTs), diarrhetic shellfish toxin (DST), amnesic shellfish toxin (AST), cyclic imines (CIs) and polyether-lactone toxins in freeze-dried phytoplankton samples. Four Vulcanodinium rugosum cultures were established from field samples and these proved to contain between 603 and 981 ng pinnatoxin (PnTx) H per mg dry weight in addition to being positive for portimine. These strains from Qatar clustered with strains from Japan and Florida based on large subunit rRNA and rRNA internal transcribed spacer gene sequences.
Abdulrahman Al Muftah; Andrew I. Selwood; Amanda J. Foss; Hareb Mohammed S.J. Al-Jabri; Malcolm Potts; Mete Yilmaz. Algal toxins and producers in the marine waters of Qatar, Arabian Gulf. Toxicon 2016, 122, 54 -66.
AMA StyleAbdulrahman Al Muftah, Andrew I. Selwood, Amanda J. Foss, Hareb Mohammed S.J. Al-Jabri, Malcolm Potts, Mete Yilmaz. Algal toxins and producers in the marine waters of Qatar, Arabian Gulf. Toxicon. 2016; 122 ():54-66.
Chicago/Turabian StyleAbdulrahman Al Muftah; Andrew I. Selwood; Amanda J. Foss; Hareb Mohammed S.J. Al-Jabri; Malcolm Potts; Mete Yilmaz. 2016. "Algal toxins and producers in the marine waters of Qatar, Arabian Gulf." Toxicon 122, no. : 54-66.
In this study, an alternative approach was proposed where excess seawater would be added only during inoculation (DD) rather than daily addition (FD). Growth and metabolite contents of Tetraselmis sp. weren't affected for daily increase of 2% NaCl salinity. Tetraselmis sp. was then cultured in DD and FD pond. In DD pond, initial culture depth was 23.5cm and its depth reduced as no water was added; for FD pond, everyday sterilized seawater was added to maintain 20cm depth. DD pond had higher biomass productivity compared to FD pond, until DD pond was deeper than FD pond; metabolite content and FAME profile of Tetraselmis sp. were also similar in both cultures. Therefore, considering the simplicity in operation, halo tolerant microalgae can be grown in DD pond method.
Probir Das; Mahmoud Ibrahim Thaher; Mohammed Abdul Quadir Mohd Abdul Hakim; Hareb Al Jabri; Ghamza Saed H.S. Alghasal. A comparative study of the growth of Tetraselmis sp. in large scale fixed depth and decreasing depth raceway ponds. Bioresource Technology 2016, 216, 114 -120.
AMA StyleProbir Das, Mahmoud Ibrahim Thaher, Mohammed Abdul Quadir Mohd Abdul Hakim, Hareb Al Jabri, Ghamza Saed H.S. Alghasal. A comparative study of the growth of Tetraselmis sp. in large scale fixed depth and decreasing depth raceway ponds. Bioresource Technology. 2016; 216 ():114-120.
Chicago/Turabian StyleProbir Das; Mahmoud Ibrahim Thaher; Mohammed Abdul Quadir Mohd Abdul Hakim; Hareb Al Jabri; Ghamza Saed H.S. Alghasal. 2016. "A comparative study of the growth of Tetraselmis sp. in large scale fixed depth and decreasing depth raceway ponds." Bioresource Technology 216, no. : 114-120.
Coagulation-flocculation can be considered as one of the least energy intensive microalgae biomass harvesting processes. However, cost of the coagulant and biomass contamination are two critical issues that need to be considered. In this study, ferric chloride (72-96mg/L) was used to effectively harvest Scenedesmus sp. (530mg/L) - grown in BG-11 media and wastewater. Reducing the culture pH below 6.5, greatly improved the harvesting efficiency. Acidic solution (pH 1.0) was very effective to recover (almost 90%) the associated iron from the harvested biomass. Scenedesmus sp. was able to grow in the supernatant and utilize the residual iron in it. Iron extracted solution, with a supplementation of 9.8mg/L ferric chloride, was able to achieve similar harvesting efficiency. The potential recovery of iron from the harvested biomass and its reuse in the harvesting can improve the biomass quality for subsequent downstream processing while reducing the cost.
Probir Das; Mahmoud Ibrahim Thaher; Mohammed Abdul Quadir Mohd Abdul Hakim; Hareb Mohammed S.J. Al-Jabri; Ghamza Saed H.S. Alghasal. Microalgae harvesting by pH adjusted coagulation-flocculation, recycling of the coagulant and the growth media. Bioresource Technology 2016, 216, 824 -829.
AMA StyleProbir Das, Mahmoud Ibrahim Thaher, Mohammed Abdul Quadir Mohd Abdul Hakim, Hareb Mohammed S.J. Al-Jabri, Ghamza Saed H.S. Alghasal. Microalgae harvesting by pH adjusted coagulation-flocculation, recycling of the coagulant and the growth media. Bioresource Technology. 2016; 216 ():824-829.
Chicago/Turabian StyleProbir Das; Mahmoud Ibrahim Thaher; Mohammed Abdul Quadir Mohd Abdul Hakim; Hareb Mohammed S.J. Al-Jabri; Ghamza Saed H.S. Alghasal. 2016. "Microalgae harvesting by pH adjusted coagulation-flocculation, recycling of the coagulant and the growth media." Bioresource Technology 216, no. : 824-829.
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 Arabian Gulf, which is characterized by an extreme desert climate. 53 autochthonous strains of microalgae were isolated from various freshwater, marine and terrestrial environments in Qatar that led to the establishment of the Qatar University Culture Collection of Cyanobacteria and Microalgae (QUCCCM). Strains were identified via ribotyping and characterized in terms of growth rate and lipid production. 13 different known genera were identified, with the distribution analysis showing Chlorella as the most abundant fresh-water known genus (22.64%), followed by Chlorocystis (13.21%). Furthermore, several novel strains were identified. Growth rate analysis evidenced a thermo and halotolerant Nannochloris isolate QUCCCM31 that is able to tolerate 45 °C and wide salinity range 35–100 ppt. Determination of lipid content and lipid profiling indicated the presence of promising strains for biodiesel production such as Nannochloris sp. (strain QUCCCM31) with a promising FAME profile for biodiesel production. This strain also produced nervonic acid, a C24:1 straight chain fatty acid of high pharmaceutical potential.
Imen Saadaoui; Ghomza Al Ghazal; Touria Bounnit; Fatma Al Khulaifi; Hareb Al Jabri; Malcolm Potts. Evidence of thermo and halotolerant Nannochloris isolate suitable for biodiesel production in Qatar Culture Collection of Cyanobacteria and Microalgae. Algal Research 2016, 14, 39 -47.
AMA StyleImen Saadaoui, Ghomza Al Ghazal, Touria Bounnit, Fatma Al Khulaifi, Hareb Al Jabri, Malcolm Potts. Evidence of thermo and halotolerant Nannochloris isolate suitable for biodiesel production in Qatar Culture Collection of Cyanobacteria and Microalgae. Algal Research. 2016; 14 ():39-47.
Chicago/Turabian StyleImen Saadaoui; Ghomza Al Ghazal; Touria Bounnit; Fatma Al Khulaifi; Hareb Al Jabri; Malcolm Potts. 2016. "Evidence of thermo and halotolerant Nannochloris isolate suitable for biodiesel production in Qatar Culture Collection of Cyanobacteria and Microalgae." Algal Research 14, no. : 39-47.
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 preservation effectiveness (cell viability and lipid productivity) was determined. The conditions tested were direct, passive, and freeze-cooling cryopreservation (technique), dimethyl sulfate and methanol (cryoprotectant), and 5 and 10 % cryoprotectant concentrations over storage durations of up to 1 year. It was shown that the cryopreservation regime is strain dependent, and strains belonging to the same genera can have different requirements. On the other hand, neutral lipid estimation, via Nile red fluorescence determination of pre- and post-cryopreserved microalgae isolates, confirmed that the lipid production is affected by the applied cryopreservation method.
Imen Saadaoui; Maryam Al Emadi; Touria Bounnit; Kira Schipper; Hareb Al Jabri. Cryopreservation of microalgae from desert environments of Qatar. Environmental Biology of Fishes 2015, 28, 2233 -2240.
AMA StyleImen Saadaoui, Maryam Al Emadi, Touria Bounnit, Kira Schipper, Hareb Al Jabri. Cryopreservation of microalgae from desert environments of Qatar. Environmental Biology of Fishes. 2015; 28 (4):2233-2240.
Chicago/Turabian StyleImen Saadaoui; Maryam Al Emadi; Touria Bounnit; Kira Schipper; Hareb Al Jabri. 2015. "Cryopreservation of microalgae from desert environments of Qatar." Environmental Biology of Fishes 28, no. 4: 2233-2240.
Mass cultivation of microalgae biomass for feed should be cost effective and toxin free. Evaporation loss in Qatar can be as high as 2 cm/d. Hence, production of marine microalgae biomass in Qatar would also require mitigating water loss as there was only very limited groundwater reserve. To address these issues, a combination of four growth conditions were applied to a 25,000 L raceway pond: locally isolated microalgae strain was selected which could grow in elevated salinity; strain that did not require silica and vitamins; volume of the culture would increase over time keeping denser inoculum in the beginning, and evaporation water loss would be balanced by adding seawater only. A local saline tolerant Nannochloropsis sp. was selected which did not require silica and vitamins. When the above conditions were combined in the pond, average areal biomass productivities reached 20.37 g/m2/d, and the culture was not contaminated by any toxic microalgae.Qatar Airways, Qatar Science & Technology Park
Probir Das; Mahmoud Ibrahim Thaher; Mohammed Abdul Quadir Mohd Abdul Hakim; Hareb Al Jabri. Sustainable production of toxin free marine microalgae biomass as fish feed in large scale open system in the Qatari desert. Bioresource Technology 2015, 192, 97 -104.
AMA StyleProbir Das, Mahmoud Ibrahim Thaher, Mohammed Abdul Quadir Mohd Abdul Hakim, Hareb Al Jabri. Sustainable production of toxin free marine microalgae biomass as fish feed in large scale open system in the Qatari desert. Bioresource Technology. 2015; 192 ():97-104.
Chicago/Turabian StyleProbir Das; Mahmoud Ibrahim Thaher; Mohammed Abdul Quadir Mohd Abdul Hakim; Hareb Al Jabri. 2015. "Sustainable production of toxin free marine microalgae biomass as fish feed in large scale open system in the Qatari desert." Bioresource Technology 192, no. : 97-104.