Abstract Thiamin (vitamin B1) is primarily produced by bacteria and phytoplankton in aquatic food webs and transferred by ingestion to higher trophic levels. However, much remains unknown regarding production, content and transfer of this water-soluble, essential micronutrient. Hence, the thiamin content of six phytoplankton species from different taxa was investigated, along with the effect of thiamin amendment on thiamin content. Furthermore, thiamin transfer to copepods was estimated in feeding experiments. Prey type, not phytoplankton thiamin content per se, was the most important factor for the transfer of thiamin, as it was lowest from filamentous Cyanophyceae and highest from more easily ingested prey like Dunaliella tertiolecta and Rhodomonas salina. Cyanophyceae had the highest thiamin content of the investigated species, eightfold higher than the lowest. Phytoplankton varied in thiamin content related to the supply of thiamin, where thiamin addition enabled higher thiamin content in some species, while copepod thiamin content was less variable. In all, thiamin transfer is not only dependent on the prey thiamin content, but also the edibility and/or digestibility is of importance. Thiamin is essential for all organisms, and this study constitutes an important building block to understanding the dynamics and transfer of thiamin in the aquatic food web.

中文翻译：

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浮游植物中硫胺（维生素 B1）的物种特异性含量及其向桡足类的转移

摘要 硫胺素（维生素 B1）主要由水生食物网中的细菌和浮游植物产生，并通过摄入转移到更高的营养水平。然而，关于这种水溶性必需微量营养素的生产、含量和转移，仍有许多未知数。因此，研究了来自不同分类群的六种浮游植物物种的硫胺素含量，以及硫胺素修正剂对硫胺素含量的影响。此外，在喂养实验中估计了硫胺向桡足类的转移。猎物类型，而不是浮游植物硫胺含量本身，是硫胺转移的最重要因素，因为它在丝状蓝藻科中最低，而在更容易摄入的猎物中最高，如杜氏盐藻和盐生红藻。蓝藻科的硫胺素含量在所调查的物种中最高，比最低的高八倍。浮游植物的硫胺素含量与硫胺素的供应有关，其中硫胺素的添加使某些物种的硫胺素含量更高，而桡足类的硫胺素含量变化较小。总之，硫胺素的转移不仅取决于猎物的硫胺素含量，而且可食性和/或消化性也很重要。硫胺素对所有生物都是必不可少的，这项研究是了解硫胺素在水生食物网中的动态和转移的重要组成部分。但可食性和/或消化性也很重要。硫胺素对所有生物都是必不可少的，这项研究是了解硫胺素在水生食物网中的动态和转移的重要组成部分。但可食性和/或消化性也很重要。硫胺素对所有生物都是必不可少的，这项研究是了解硫胺素在水生食物网中的动态和转移的重要组成部分。