Edaphic algae as sustainable biofactories for high-valued nutraceutical and pharmaceutical products

Our present-day knowledge on the phytochemical characterization of edaphic microalgae is still largely limited due to the difficult challenges of species isolation, cultivation and mass production. In this investigation, we highlighted the significant values of phytochemical compounds characterized in four different edaphic algal species (Vaucheria geminata, Pleurochloris pyrenoidosa, Botrydiopsis eriensis, and Scenedesmus obliquus) for the promising and possible utilization in food, feed and pharmaceutical industries. Results revealed maximum content of amino acids in P. pyrenoidosa with dominance of arginine, glutamic acid and alanine. Furthermore, the ratio of essential to non-essential amino acids was more or less the same in all algal taxa. High-performance liquid chromatography (HPLC) analysis for sugars showed that mannose was the dominant sugar in both V. geminata and B. eriensis whilst arabinose and rhamnose constituted the major sugars in P. pyrenoidosa and S. obliquus, respectively. Using Gas chromatography–mass spectrometry (GC-MS), 21 different fatty acids methyl esters were identified in all algal taxa with dominance of C16/C18 types. Note of worth, polyunsaturated fatty acids were only detected in the three yellow green algae V. geminata, P. pyrenoidosa, and B. eriensis. The main representatives of fatty acids identified were palmitic acid in V. geminata, linoleic acid in P. pyrenoidosa, ω−3 α-linolenic acid in B. eriensis, and ω−9 oleic acid in S. obliquus. Considering the high-valued natural compounds characterized in all the above mentioned edaphic algal taxa, we therefore can suggest them to be highly utilized in the sustainable development of food, feed and pharmaceutical industries.