Identification of carotenoids in four species of copepods from the Great Barrier Reef

The main carotenoids of four species of copepods found in the Great Barrier Reef were separated by chromatographic techniques including reversed-phase HPLC and identified using chemical and spectroscopic methods and by mass spectrometry.Temora turbinata, which is found in inshore waters was collected from Bowling Green Bay. Centropages furcatus, found in inshore waters and on reefs, and Undinula vulgaris, found near the surface in daylight were collected from Palm Passage. These three species were collected from surface waters using a 300 µm mesh net. Euchaeta russelli, which is found between 100-200m depth was obtained from Myrmidon Reef, on the outer shelf, by oblique towing from 150 meters using a 500 µm mesh net. Carotenoids and caroteno-proteins are common pigments in crustacea. Colour in some copepods has been observed to be variable, depending on the environment they inhabit. Colour variability may also be seasonal and may occur within a species. Analyses were made to identify and compare the types of pigments occurring in four species of copepods, Temora turbinata, Centropages furcatus, Undinula vulgaris and Euchaeta russelli, which exhibit similar variations.

本研究针对大堡礁海域发现的4种桡足类（Copepods）的主要类胡萝卜素展开分析：采用包括反相高效液相色谱（reversed-phase HPLC）在内的色谱技术完成分离，并通过化学方法、光谱学方法及质谱法（mass spectrometry）完成鉴定。其中，栖息于近岸海域的Temora turbinata采集自鲍灵格林湾（Bowling Green Bay）；栖息于近岸海域及珊瑚礁的Centropages furcatus以及白昼活动于近表层水域的Undinula vulgaris均采集自棕榈水道（Palm Passage），上述三个物种均通过孔径300微米的浮游生物采集网于表层水域采集获得。栖息于100~200米水深的Euchaeta russelli则采集自外陆架的迈尔密东珊瑚礁（Myrmidon Reef），通过孔径500微米的网具以斜拖方式从150米水深处获取。类胡萝卜素与类胡萝卜素蛋白是甲壳类（Crustacea）动物中常见的色素组分，已有研究观察到部分桡足类的体色会因栖息环境的差异而发生变化，此类体色变异还可能具有季节性，且可发生于同一物种内部。本研究对上述4种桡足类——Temora turbinata、Centropages furcatus、Undinula vulgaris及Euchaeta russelli——体内的色素类型进行了鉴定与比较，这4个物种均表现出相似的体色变异特征。