红藻糖苷对超低温冻存微藻的保护作用

为研究红藻糖苷对超低温冻存微藻细胞的保护作用，研究将3种不同的微藻置于含10% DMSO和不同浓度红藻糖苷的冻存液中，冻存并解冻后，以流式细胞仪检测细胞存活率，测定复养后藻株的生长曲线及相关生理参数。结果显示，由于冷冻损伤，冻存后各种藻细胞的生长速率、细胞密度及生理指标都显著性下降，而红藻糖苷协同DMSO能够显著增加细胞的存活率，尤其15%红藻糖苷能将紫球藻存活率提升20%（P0.05）；生长曲线得到明显改善；且对PSII最大光能转化效率也有显著性提高（P0.05）。总体结果来看，红藻糖苷对超低温冻存微藻，特别是紫球藻具有明显的保护作用，且效果强于蔗糖。

THE CRYOPROTECTIVE EFFECT OF FLORIDOSIDE ON MICROALGAE

This study was designed to determine the protective effects of floridoside on cryopreservation of marine microalgae. Three strains of microalgae were cryopreservated by combination of 10% DMSO and different concentrations of floridoside. After frozen-thaw process, the cell viability was determined by performing flow cytometry with fluorescein diacetate (FDA). Growth curve and physiological parameter (Fv/Fm) were also detected. Results revealed that freezing caused significant decrease on the growth rate of three microalgae, moreover, growth curve and physiological parameters of thawed microalgae were also impacted severely. Combination of floridoside and DMSO significantly improve viability of three microalgae. Especially, 15% of floridoside could increase the cell viability of Porphyridium cruentum by 20% (P0.05) than that only using DMSO. Growth curve were resumed remarkably, and physiological parameter, PSII was also improved. These findings indicated that appropriate concentration of floridoside might be used as a better cryoprotectant to cryopreserve microalgal species, especially P. cruentum. The protect effect was better than sucrose.