西沙群岛海域纲比亚藻种群结构及产毒特征研究

With the global warming and ocean acidification, coral reef is dying and covered with seaweed or seagrass. Under these scenarios, Gambierdiscus spp. would thrive and the crisis of Ciguatera fish poisoning (CFP) appear to be increasing. Gambierdiscus spp. has been found in our country, including the South China Sea Islands and the coastal of South China coral reef waters. However, the sporadic nature of CFP events, coupled with a lack of sustained scientific research on the Gambierdiscus spp. structure, environmental and physiological factors that contribute to CFP production, has hindered progress in the development of management strategies to protect people against exposure to ciguatoxins. We propose to conduct a morphological, physiological and molecular study of Gambierdiscus spp. in the Xisha Islands to find out the Gambierdiscus spp. structure and locate the ciguatoxin-producing species, the relationship among the Gambierdiscus spp., environmental factors and ciguatoxin production, excavate the indicator Gambierdiscus species, and to establish a rapid and accurate method of CFP monitoring based on Gambierdiscus spp.

全球气温上升及海洋酸化，导致大量珊瑚死亡并被大型及丝状海藻覆盖，为栖息于珊瑚碎屑或大型藻类的表面的雪卡毒素的毒源生物有毒纲比甲藻大量繁殖，使广大海产品消费者受雪卡毒素中毒的威胁日趋严重。纲比亚藻及雪卡毒素在我国南海诸岛和华南沿海地区的珊瑚礁海域均有发现。然而对西沙群岛海域纲比亚藻的具体种类，地理分布情况及产毒特性等还知之甚少。为此，本课题从纲比亚藻的种群结构入手，采用传统分类学和分子生物学方法鉴定产毒藻种；后通过室内模拟查明主要藻种的产毒特征、条件与规律，阐释纲比亚藻种群结构—环境因子—毒素产生的互作机制；确定西沙群岛海域的主要产毒藻种和毒素组成；进而探索以产毒纲比亚藻种作为雪卡毒素污染物指示种的可行性。

全球气温上升及海洋酸化，导致大量珊瑚死亡并被大型及丝状海藻覆盖，为栖息于珊瑚碎屑或大型藻类的表面的雪卡毒素的毒源生物有毒纲比甲藻大量繁殖，使广大海产品消费者受雪卡毒素中毒的威胁日趋严重。纲比甲藻及雪卡毒素在我国南海诸岛和华南沿海地区的珊瑚礁海域均有发现。然而对西沙群岛海域纲比亚藻的具体种类，地理分布情况及产毒特性等还知之甚少。为此，本课题从纲比亚藻的种群结构入手，采用传统分类学和分子生物学方法鉴定产毒藻种；后通过室内模拟查明主要藻种的产毒特征、条件与规律；进而确定西沙群岛海域的主要产毒藻种和毒素组成。旨在建立一种以纲比亚藻种为监测对象，快速和准确的雪卡毒素监测方法，同时将产毒种作为生物指示物。经过三年的研究工作，项目组在西沙岛礁获得了7株纲比亚藻，分别为G. pacificus，G. silvae和Gambierdiscus sp. Type 5，其中仅G. pacificus产血卡毒素，其余藻种均未检测到毒素，毒素种类为CTX2和CTX3毒素，未检测到CTX1和MTX毒素，产毒浓度为0.0249 pg/cell~0.0384 pg/cell，本次研究所获得的G. pacificus可作为西沙血卡毒素产毒藻的潜在指示生物，该研究成果有望应用于西沙海域海产品血卡毒素监测及环境监测应用中。