Kusumaningtyas Pintaka, Nurbaiti Santi, Suantika Gede, Amran Muhammad Bachri, Nurachman Zeily
Biochemistry Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Indonesia.
Microbial Biotechnology Research Group, School of Life Sciences and Technology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Indonesia.
Appl Biochem Biotechnol. 2017 Aug;182(4):1605-1618. doi: 10.1007/s12010-017-2421-8. Epub 2017 Jan 23.
Microalgae-derived oils have potential as a biofuel feedstock. To produce microalgal oils at a large scale, large amounts of nutrients and energy are needed to grow the algae. In this study, we evaluated three types of agricultural fertilizer (AF)-based culture media (AF1, AF2, and AF3) based on a previously published enriched seawater (ES) medium to produce biomass and oils from Thalassiosira sp. Under laboratory conditions, the highest cell productivity of Thalassiosira sp. was obtained with the AF3 medium. Thalassiosira sp. cultured in the AF3 medium produced 10.4 ± 0.9 mg L dayoils, which is significantly higher than the 5.8 ± 0.7 mg L dayproduced in the ES medium. The higher production was due to the presence of nitrate and trace elements, both of which played roles in enhancing biomass and oil content, respectively. During cell growth, resting spores appeared inside the cells and were a marker to harvest the cells. Because of the abundant availability of sunlight in the tropics during the year, the oil production of Thalassiosira sp. in the AF3 medium was scaled up using outdoor photobioreactors under different weather conditions (rainy and dry seasons). Thalassiosira sp. produced more unsaturated fatty acids during the rainy season and produced more saturated fatty acids during the dry season. This study also demonstrated that it was possible to culture Thalassiosira sp. under outdoor conditions using a low-cost agricultural fertilizer-based culture medium (AF3 medium) to produce biodiesel feedstock with an annual production of 8.1 ± 0.4 t ha during the dry season and of 23.9 ± 6.8 t ha during the rainy season.
微藻衍生油有作为生物燃料原料的潜力。为了大规模生产微藻油，需要大量营养物质和能量来培育藻类。在本研究中，我们基于之前发表的富海水（ES）培养基，评估了三种基于农业肥料（AF）的培养基（AF1、AF2和AF3），用于从硅藻属生产生物质和油。在实验室条件下，使用AF3培养基获得了硅藻属的最高细胞生产力。在AF3培养基中培养的硅藻属每天产生10.4±0.9毫克/升油，这显著高于在ES培养基中产生的5.8±0.7毫克/升/天。产量更高是由于硝酸盐和微量元素的存在，它们分别在提高生物量和油含量方面发挥了作用。在细胞生长过程中，静止孢子出现在细胞内，是收获细胞的一个标志。由于热带地区一年中阳光充足，在不同天气条件（雨季和旱季）下，使用室外光生物反应器扩大了AF3培养基中硅藻属的产油量。硅藻属在雨季产生更多不饱和脂肪酸，在旱季产生更多饱和脂肪酸。本研究还表明，使用低成本的基于农业肥料的培养基（AF3培养基）在室外条件下培养硅藻属以生产生物柴油原料是可行的，旱季年产量为8.1±0.4吨/公顷，雨季为23.9±6.8吨/公顷。
