Effects of light intensity and culture medium on the chemical composition and growth parameters of Nannochloropsis oculata and Porphyridium cruentum

Abstract

Microalgae are considered sources of compounds of high nutritional value. This study determined whether 400 μE/m2/s (HL) and 80 μE/m2/s (LL) light intensities and algal medium (AM) and f/2 Guillard medium (f/2GM) influence kinetic parameters, moisture, ash, lipids, carbohydrate, protein, amino acid, vitamins contents of the microalgae Nannochloropsis oculata and Porphyridium cruentum. N. oculata recorded the highest cell density of 341.64 ± 2.36 × 106 cells/ml under HL in AM, while P. cruentum achieved 56.60 ± 1.33 × 106 cells/ml under LL in f/2GM. The highest lipids content was 28.66 ± 0.14% for N. oculata, and 13.40 ± 0.25% for P. cruentum, both under LL in f/2GM. The higher carbohydrates content was obtained in AM, 30.41 ± 1.10% at LL and 47.57 ± 1.52% at HL for N. oculata and P. cruentum respectively. The protein content was 34.53 ± 1.33% and 26.03 ± 1.00% both under HL in AM for N. oculata and P. cruentum respectively. In terms of amino acid and vitamins composition, only N. oculata presented high content of essential amino acids and vitamins α‐tocopherol, β‐sitosterol and β‐carotene, based on these results, N. oculata could be recommended as a rich source of lipids, protein, amino acid and vitamin and P. cruentum for their high carbohydrate.