Assessment of taxonomically diverse Chlorococcum species and Chroococcus species for cell density, pigments, biochemical components, and fatty acid composition for fuel/food applications

Abstract

In this study, a comparison of two microalgal and two cyanobacterial species for biomass yield, carbohydrate, protein, lipids, chlorophyll, and fatty acids was carried out to evaluate their potential for fuel/food/feed applications. Among the tested green algal strains, Chlorococcum sp. isolate 4, Chlorococcum sp. isolate 5, and cyanobacterial strains Chroococcus sp. isolate 1, Chroococcus sp. isolate 2, Chlorococcum sp. isolate 4 were found to yield higher biomass, i.e. about 1.33 g/L (under aeration), 1.21 g/L (no aeration condition) on the 24th day and it also showed higher chlorophyll content of 14.3 mg/g dry cell weight than other species. Besides, a maximal carbohydrate and protein content of 63.7 % and 27.3 %, respectively, were noticed in Chlorococcum sp. isolate 4. The lipid contents of Chlorococcum sp. isolate 4, Chlorococcum sp. isolate 5, Chroococcus sp. isolate 1 and Chroococcus sp. isolate 2 were 18.3, 16.7, 4.7, and 3.8 %, respectively. Eventually, the biodiesel production potential of Chlorococcum sp. isolate 4 showed 29.83, 9.11, 8.22, 19.42, 9.22 and 10.68 % of palmitic, palmitoleic, stearic, oleic, linoleic, and linolenic acid, respectively. Among the strains studied, Chlorococcum sp. isolate 4 can be proposed to be an ideal feedstock for the production of biodiesel and other high-value products due to its higher content of biomass, proteins, carbohydrates, total lipids, and desirable fatty acid composition.