Phaeocystis globosa is regarded as a notoriously harmful algal bloom species. Suppressing harmful algae using algicidal substances extracted from plants is considered an effective method. The physiological and biochemical processes of P. globosa were explored by exposure to different concentrations of aqueous extracts of Cyperus rotundus. All treatments indicated various inhibitory effects on the algal growth compared to the control samples without adding extracts. At 48 h, the 4, 8, and 16 mg/mL treatment groups showed a significant inhibitory effect, consistent with a decrease in the chlorophyll-a content and photosynthetic efficiency. The images of the transmission electron microscope (TEM) further confirmed that a subset of the cells in the treatment groups exhibited morphological anomalies. The algicidal active substances were mainly identified as phenolic acids containing maximal content of quinic acid in aqueous extracts according to the results of ultra-high-performance liquid chromatography-tandem time-of-flight mass spectrometer (UPLC-HRMS). The 50% anti-algal effect concentration of quinic acid was 22 mg/L at 96 h (EC50–96h). Thus, the phenolic acids might be considered as major inhibitors of the growth of P. globosa. These results demonstrated that the aqueous extracts of C. rotundus could potentially control the growth of P. globosa.

中文翻译：

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有害藻类Phaeocystis globosa的光合效率和细胞完整性反映香附水提物的杀藻活性

Phaeocystis globosa 被认为是一种臭名昭著的有害藻华物种。使用从植物中提取的藻类物质抑制有害藻类被认为是一种有效的方法。通过暴露于不同浓度的香附的水提取物，探索了P. globosa 的生理和生化过程。与不添加提取物的对照样品相比，所有处理均显示出对藻类生长的各种抑制作用。在 48 h 时，4、8 和 16 mg/mL 处理组显示出显着的抑制作用，与​​叶绿素 a 含量和光合效率降低一致。透射电子显微镜 (TEM) 的图像进一步证实了治疗组中的一部分细胞表现出形态异常。根据超高效液相色谱-串联飞行时间质谱仪(UPLC-HRMS)的结果，主要鉴定出水提物中奎宁酸含量最高的酚酸类杀藻活性物质。奎宁酸的 50% 抗藻作用浓度在 96 小时 (EC50–96h) 时为 22 mg/L。因此，酚酸可能被认为是球状假单胞菌生长的主要抑制剂。这些结果表明 C. rotundus 的水提取物可以潜在地控制 P. globosa 的生长。因此，酚酸可能被认为是球状假单胞菌生长的主要抑制剂。这些结果表明 C. rotundus 的水提取物可以潜在地控制 P. globosa 的生长。因此，酚酸可能被认为是球状假单胞菌生长的主要抑制剂。这些结果表明 C. rotundus 的水提取物可以潜在地控制 P. globosa 的生长。