State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 311300, China; Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A&F University, Hangzhou 311300, China.
State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 311300, China; Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A&F University, Hangzhou 311300, China.
Bioresour Technol. 2024 Jul;403:130898. doi: 10.1016/j.biortech.2024.130898. Epub 2024 May 24.
Astaxanthin is a high-value natural antioxidant, and can be accumulated in Microcystis aeruginosa. To enhance astaxanthin accumulation in the microalgae by using salt stress, the cell growth, photosynthetic abilities, reactive oxygen species (ROS) levels, astaxanthin and its precursor content, and gene expression were investigated under NaCl and KCl stresses. The two salt stresses inhibited the cell growth by lowering photosynthetic abilities and raising ROS levels. During the 6-day treatment, the two salt stresses improved the levels of astaxanthin, precursors (β-carotene and zeaxanthin) and carotenoids, which might be caused by the raised ROS up-regulating expression of 7 related genes. At the same concentration, KCl stress showed stronger inducing effect on astaxanthin and its precursor production than NaCl stress, due to higher expression of related genes. Therefore, NaCl and KCl stresses have obvious ion differences on astaxanthin accumulation, of which KCl stress is more suitable for the high-value antioxidant production from microalgae.
虾青素是一种高附加值的天然抗氧化剂，可以在铜绿微囊藻中积累。为了通过盐胁迫来提高微藻中虾青素的积累，研究了 NaCl 和 KCl 胁迫下细胞生长、光合能力、活性氧（ROS）水平、虾青素及其前体含量以及基因表达的变化。两种盐胁迫通过降低光合能力和提高 ROS 水平来抑制细胞生长。在 6 天的处理过程中，两种盐胁迫均提高了虾青素、前体（β-胡萝卜素和玉米黄质）和类胡萝卜素的水平，这可能是由于 ROS 升高上调了 7 个相关基因的表达所致。在相同浓度下，KCl 胁迫对虾青素及其前体产生的诱导作用强于 NaCl 胁迫，这是由于相关基因的表达更高。因此，NaCl 和 KCl 胁迫对虾青素积累有明显的离子差异，其中 KCl 胁迫更适合从微藻中生产高附加值的抗氧化剂。
