Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China.
Yunnan Academy of Forestry and Grassland, Kunming 650051, China.
Bioresour Technol. 2021 Jan;320(Pt B):124418. doi: 10.1016/j.biortech.2020.124418. Epub 2020 Nov 16.
The effects of γ-aminobutyric acid (GABA) on the biomass and astaxanthin and lipids production in Haematococcus pluvialis under combined salinity stress and high-light stresses were investigated. The results showed that the highest biomass (1.65 g L), astaxanthin production (3.86 mg L d) and lipids content (55.11%) in H. pluvialis LUGU were observed under the 0.25 mM GABA treatment. Moreover, compared with salinity and high-light stress, GABA treatment also increased the transcript levels of biosynthesis genes, the contents of endogenous GABA and carbohydrates but decreased reactive oxygen species (ROS) levels. Further evidence revealed that intracellular GABA could regulate cell growth, astaxanthin production and lipids synthesis by mediating carotenogenesis, lipogenesis and ROS signalling. Collectively, this study provides a combined strategy for promoting the coproduction of astaxanthin and lipids and sheds light on the regulatory mechanism through which GABA affects cell growth, astaxanthin production and lipids biosynthesis in H. pluvialis under unfavourable conditions.
研究了γ-氨基丁酸（GABA）对盐度和高光胁迫下雨生红球藻生物量、虾青素和脂质生产的影响。结果表明，在 0.25 mM GABA 处理下，雨生红球藻 LUGU 的生物量（1.65 g/L）、虾青素产量（3.86 mg L d）和脂质含量（55.11%）最高。此外，与盐度和高光胁迫相比，GABA 处理还增加了生物合成基因的转录水平、内源性 GABA 和碳水化合物的含量，但降低了活性氧（ROS）水平。进一步的证据表明，细胞内 GABA 通过调节类胡萝卜素生物合成、脂肪生成和 ROS 信号转导来调节细胞生长、虾青素生产和脂质合成。总之，本研究为促进虾青素和脂质的共生产提供了一种联合策略，并揭示了 GABA 在不利条件下影响雨生红球藻细胞生长、虾青素生产和脂质生物合成的调控机制。
