Diatoms have recently emerged as new promising sources of fucoxanthin and eicosapentaenoic acid (EPA). Most applied studies in this area have focused on marine diatoms whereas the characterization of freshwater diatom metabolism has been restricted to ecophysiological studies. Here, we describe a novel culture medium for freshwater diatoms, the FDMed medium, and we demonstrate that it supports high biomass, fucoxanthin, and EPA production yields in photoautotrophic batch cultures of Sellaphora minima and Nitzschia palea. Growth was monitored for 21 days, fucoxanthin and EPA concentrations were assayed all along cultivation processes, and results were compared to those obtained for two other media (WC and Modified COMBO (MCOMBO)). The FDMed medium was found to increase biomass yields comparatively to MCOMBO medium (5–7-fold higher algal concentration at the stationary phase in S. minima and N. palea, respectively) while WC medium enables nearly no growth. The evolution of nitrate, silicate, and phosphate concentrations in culture media indicated a much better balance of macroelements in the FDMed medium. Fucoxanthin contents within the biomass remained very stable in the FDMed medium compared to the other media, in which it gradually decreases, and the best results (around 7.5 mg g^-1 dry weight ) were obtained for S. minima in the FDMed medium. EPA could only be measured in the FDMed medium and the highest content (14.0 mg EPA g^-1 dry weight) was recorded in N. palea. This work demonstrates the great industrial potential of freshwater diatoms and provides an efficient culture medium for those organisms.

硅藻最近已成为岩藻黄质和二十碳五烯酸（EPA）的新的有希望的来源。该领域的大多数应用研究都集中在海洋硅藻上，而淡水硅藻代谢的特征仅限于生态生理学研究。在这里，我们描述了一种用于淡水硅藻的新型培养基，即FDMed培养基，并且我们证明了它在Sellaphora minima和Nitzschia palea的光合自养分批培养中支持高生物量，岩藻黄质和EPA产量。。监测生长21天，在整个培养过程中测定岩藻黄质和EPA的浓度，并将结果与​​其他两种培养基（WC和改良COMBO（MCOMBO））获得的结果进行比较。所述FDMed介质，发现增加的生物质的产率相对于MCOMBO介质（较高浓度的藻类在固定相5-7倍S.最小值和N.内稃而WC介质使得几乎没有生长，分别地）。培养基中硝酸盐，硅酸盐和磷酸盐浓度的变化表明FDMed培养基中的宏元素之间的平衡要好得多。与其他培养基相比，FDMed培养基中生物质中的岩藻黄质含量保持非常稳定，在逐渐降低的情况下，最佳结果（约7.5 mg g ^-1）在FDMed培养基中获得最小链霉菌的干重）。EPA只能在FDMed培养基中测量，最高含量（14.0 mg EPA g ^-1干重）记录在尼泊尔猪笼草中。这项工作展示了淡水硅藻的巨大工业潜力，并为这些生物提供了有效的培养基。