Growth, lipid content, and fatty acid profile of freshwater cyanobacteria Dolichospermum affine (Lemmermann) Wacklin, Hoffmann, & Komárek by using modified nutrient media

• Published in: Aquaculture international Vol. 28; no. 3; pp. 1371 - 1388
• Main Author: Yalcin, Dilek
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01-06-2020; Springer Nature B.V
• Subjects: Analytical methods; Batch culture; Biomass; Biomedical and Life Sciences; Carbohydrates; Carotenoids; Chlorophyll; Chlorophyll a; Density; Desmodium affine; DNA; Dolichospermum; Fatty acids; Fourier transforms; Freshwater; Freshwater & Marine Ecology; Growth rate; Infrared spectroscopy; Inland water environment; Life Sciences; Lipids; Metabolites; Nucleotide sequence; Oleic acid; PCR; Phosphates; Phosphorus; Pigments; Profiles; Secondary metabolites; Starvation; Zoology; Modified culture medium; TAG; Fatty acid; Lipid
• ISSN: 0967-6120; 1573-143X
• DOI: 10.1007/s10499-020-00531-2

In this study,
Dolichospermum affine
was cultivated under starvation and limitation conditions, using six different concentrations of nitrate (NaNO
3
) and phosphate (K
2
HPO
4
) in BG-11 medium. The biomass, pigments, proteins, carbohydrates, lipids, triacylglycerol-TAG, and fatty acid responses to different modified media were examined in terms of cell density, dry biomass, optical density, growth rate, chlorophyll-a, carotene content, and lipid productivity. Molecular characterization of
D
.
affine
isolates was performed using Fourier transform–infrared spectroscopy (FT-IR) and polymerase chain reaction (PCR). In the 20-day batch culture period, one of the modified media, %50 N and P limitation (N-P
Limitation
), exhibited higher values than the others in terms of cell density (1.41 × 10
7
cells/mL), dry biomass (1.68 gL
−1
), optical density (1.26), growth rate (0.48 day
−1
), chlorophyll-a (3.76 μg L
−1
), and total carotenoid (12.99 μg L
−1
). The maximum percentage lipid content of
D
.
affine
was obtained in the control group at 10.67%. Fatty acid profiles have been investigated in six conditions and consisted of 10 fatty acids. The basic saturated fatty acid palmitic acid was (C16:0) for all conditions, and its rate was 40.61% for starvation of N and P (N-P
Deprivation
) conditions. Oleic acid (C18:1) rate was detected in all groups, but the highest rate was found in the control group with 33.72%. In all conditions, TAG values were found similar, but the highest value was determined at 50% P and 100% N (P
Limitation
-N
Control
) (27.5%) modified media. Carbohydrate content (20.37%) was found to be high under N and P starvation (N-P
Deprivation
), while protein content (66.92%) was high under 50% N and 100% P (N
Limitation
-P
Control
) conditions. The results obtained from this study showed that nitrogen and phosphorus starvation and limitation affecting the biomass, valuable secondary metabolites and lipid accumulation and affected the fatty acid composition of
D
.
affine
cultures.