类胡萝卜素是重要的光合色素和抗氧化剂，具有调节植物生长、发育和环境适应等功能。为了深入了解坛紫菜中类胡萝卜素在不同生长阶段中的合成代谢过程，实验采用超高效液相色谱-三重四极杆质谱联用技术分析坛紫菜丝状体和不同采收期叶状体中类胡萝卜素组成差异。结果显示，甲醇-二氯甲烷 (1∶1，体积比)为提取溶剂，液料比1∶10，超声时间30 min是坛紫菜类胡萝卜素的最佳提取条件；优化色谱条件，16种类胡萝卜素标准品的分离度达到1.5，最低检测限为1.57~4.96 ng/mL。在坛紫菜两种世代体中共检测到8种类胡萝卜素，分别属于α-胡萝卜素合成途径 (α-胡萝卜素、ε-胡萝卜素、α-隐黄质和叶黄质)和β-胡萝卜素合成途径 (β-胡萝卜素、β-隐黄质、玉米黄质和环氧玉米黄质)。叶状体中的总类胡萝卜素含量和最大光化学效率(F_v/F_m)分别是丝状体1.4和1.5倍。其中，丝状体中仅β-隐黄质的含量显著高于叶状体 (3.7倍)，而α-胡萝卜素、β-胡萝卜素、ε-胡萝卜素、玉米黄质、叶黄质和α-隐黄质的含量却是一水叶状体的22.7%~67.0%。在叶状体阶段中，玉米黄质和叶黄质是其主要的类胡萝卜素，除β-胡萝卜素外，其余7种类胡萝卜素的含量随着采收期的延长而整体呈现下降趋势。研究表明，类胡萝卜素的含量与坛紫菜生长阶段和生存环境息息相关，强光、高温等复杂环境因素促进叶状体中类胡萝卜素大量合成，参与胁迫防御，维持藻体快速生长，而耐高温的丝状体和低温弱光环境下叶状体因氧化损伤减弱，降低了类胡萝卜素的合成。本研究为坛紫菜品种选育和健康养殖提供了重要的实验数据。

Carotenoids, essential photosynthetic pigments and antioxidants, regulate plant growth, development and environmental adaptation. This study aimed to elucidate the carotenoid responses in Neoporphyra haitanensis at different growth stages by analyzing carotenoid compositions in conchocelis and thallus across various generations and harvest stages using ultra-liquid chromatography-triple quadrupole mass spectrometry. Optimal extraction conditions were determined as methanol-dichloromethane (1∶1, V/V) as the solvent, a solid-to-liquid ratio 1∶10, and a 30 min ultrasonic time. Liquid chromatography parameters were optimized to achieve a resolution of 1.5 for 16 carotenoids, with a detection limit of 1.57-4.96 ng/mL. Eight carotenoids were detected in two generations of N. haitanensis, associated with the α-carotene synthesis pathway (α-carotene, ε-carotene, α-cryptoxanthin and lutein) and the β-carotene synthesis pathway (β-carotene, β-cryptoxanthin, zeaxanthin and antherxanthin). The total carotenoid content and the photochemical efficiency (F_v/F_m) in the thallus were 1.4- and 1.5-fold higher, respectively, than in the conchocelis. Notably, β-cryptoxanthin content in conchocelis, which has a stable growth state and low antioxidant requirements, was 3.7 times higher than thallus, while the contents of α-carotene, β-carotene, ε-carotene, zeaxanthin, lutein and α-cryptoxanthin were 22.7%-67.0% of those in the thallus. Zeaxanthin and lutein were the predominant carotenoids in the thallus. Except for β-carotene, the contents of the other seven carotenoids decreased with the extension of the harvest period. The study indicates that carotenoid content is closely related to the growth stage and survival environment of N. haitanensis. Rapid carotenoid synthesis in the early thallus period is likely a response to strong light and high temperature stresses, facilitating stress defense and growth. Conversely, a decreased synthesis rate in conchocelis and the late thallus period suggests a reduced antioxidant requirement. These findings provide valuable experimental data for further development of cultivars and seaweed farming practices.

S 917.3

宁波市重点研发计划暨“揭榜挂帅”项目(2023Z121)；宁波市公益科技项目 (2021S063)；国家现代农业产业技术体系专项 (CARS-50)