Desert Microalgae: Potential Source for Food Security in Qatar
Authors: Rasheed Rihab , Dalgamouni Tasneem , Saadaoui Imen , Al Jabri Hareb 
Published: July 2019

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 stocks as well as the human beings. Micro algae render most of the essential nutrients such as amino acids, proteins, sugars, fatty acids, vitamins etc. which will supplement and provide a balanced mixture of nutrients to the animals there by enhancing the quality of eggs, meat, fish meat and other co products. 50 strains of micro algae that can be potentially useful for the food security program were screened from QUCCM (Qatar University Culture Collection of Cyanobacteria and Micro algae) for their biochemical composition.

Following the screening process,10 eminent strains such as Chlorella sp, Nannochloris sp, Tetraselmis sp, Desmodesmus sp, Myconastes sp, Chlamydomonas sp, Scenedesmus sp, Chlrococcum sp, Ourococcus sp, Chlorocystis sp representing major micro algal taxa were chosen whose protein content was estimated to be (20–45%) and carbohydrates (8–20%) that may best be adapted to Qatar's environmental conditions. Proteins are composed of different amino acids and hence the nutritional quality of a protein is determined basically by the content, proportion and availability of its amino acids. Therefore, Amino acid profiling was also performed for few selected strains using the method adapted from Heinrikson and Meredith 1984 and quantified by HPLC using UV detector. The profiles obtained for some of the strains showed similarity and richness in all the essential amino acids particularly high in glycine, serine, aspartate and glutamate. On the other hand, the micro algal polysaccharides extracted by acid hydrolysis was quantified using HPLC coupled with RI detector. The profiles exhibited variability in sugar compositions showing the presence of mainly glucose, fructose and xylose in different amounts. Above all, most of the strains displayed a reasonably fair growth rate (0.2–1.5 per day approx.) which further supports algae being used as feed by attaining more mass in lesser time.

Therefore it was highlighted that micro algae have a very diverse profile for metabolites under standard growth conditions. Chlorella sp was rich in its protein content while Chlorocystis sp exhibited its importance in sugars. The presence of all essential amino acids in microalgae helps fulfill the missing nutritional requirements in animals and humans. Micro algae are able to enhance the nutritional content of conventional food preparations and therefore positively affect the life of organisms consuming it. Based on the available information on toxic properties or any other adverse effects of algae, none of the them caused any anomalies on feeding experiments during various toxicity tests making them completely safe for use as feed (Chamorro, 1980). It can be concluded that microalgae have an important role in food security and the nutritional profiles of Qatari isolates closely matched the overseas strains. A segment of World algal production can be used for animal feed application and aquaculture.

Keywords

Microalgae, Protein, Carbohydrate, Amino acids, Amino acid profiling, HPLC