Effect of Various Bicarbonate Supplements on Biodiesel Production and Valuable Biochemical Components of the Marine Eustigmatophyceae Nannochloropsis oculata (Droop)

Abstract

Microbial breeding media must be cost-effective, enable high growth, meet exact requirements and be readily available. The effect of different levels of sodium bicarbonate (SB) [25, 50, 75 and 100%] in the growth medium on the biochemical constituents (protein, carbohydrates, lipids, fatty acids, and amino acids) of the Nannochloropsis oculata was assessed compared to the F/2 Guillard standard medium. The obtained results revealed that the chemical constituents of N. oculata were influenced by the used level of sodium bicarbonate. The highest total protein, carbohydrate contents, and the maximum percentage of essential amino acids (EAA) (59.68 %) were obtained by using the B1 medium (25% SB) as compared to the control (100% F/2). The highest total lipid content was achieved by using the B4 medium (100% SB) producing (20.09 %). In accordance, the highest total saturated fatty acids percentage (TSFA) of N. oculata was recorded by B4 medium. However, the highest total unsaturated fatty acids percentage (USFA) was exhibited by the B1 medium. The EN 14214 and ASTM D-6751 analyzes of the production of biodiesel have shown that the produced biodiesel by B4 medium (100% SB) and the control media of high quality. In conclusion, the addition of sodium bicarbonate is an excellent policy to increase chemical composition and lipid accumulation. The present study recommended taming results foreither biodiesel production or aquaculture feeding by using proposed B4 medium as a lipid promoter or B1 medium as a protein promoter.