Journal of Aquatic Ecology

Many algae produce large amounts of oil that can be converted to biodiesel. In this study, the microalgae species including Spirulina platensis, Chlorella vulgaris, Scenedesmus obliqus, and seaweeds including Sargassum sp. and Padina sp. were selected and cultured in suitable condition to compare the lipids composition. According to the results, the highest and the lowest amounts of saturated fatty acids were observed in Sargassum sp. (60.6%) and C. vulgaris (79/21%), respectively. The saturated fatty acids including acid Lauric (C12: 0), Meristic acid (C14: 0), Pentadecanoic acid (C15: 0), Palmitic acid (C16: 0), and Stearic acid (C18: 0) were observed in varying amounts in all species. Most of the diversity of fatty acids were observed in S. obliquus with 22 fatty acids while that was 13 in Sargassum sp. and Padina sp. and 12 and 10 in C. vulgaris and S.platensis species, respectively. The greatest amount of unsaturated fatty acids was measured in C. vulgaris., The greatest amount of unsaturated fatty acids in microalgae and seaweeds were linolenic acid (C18: 3) and oleic acid (C16:1), respectively. The highest amount of EPA and DHA was observed in S. obliquus. The highest percentage of 1-band, 2-band, 3-band, and poly-band unsaturated fatty acids was observed in Padina sp.,  S. platensis,   C. vulgaris, and Scenedesmus obliquus, respectively. The most fatty acids composition of studied microalgae consisted unsaturated fatty acids, while in seaweeds, saturated fatty acids were the most frequent fatty acids.