Effects of Different Culture Conditions and Growth States on the Structure and Hemostatic Properties of Coscinodiscus sp.

As a renewable marine inorganic material, Coscinodiscus sp. has significant potential in the field of rapid hemostasis. However, the low yield of Coscinodiscus sp. seriously limits the application. In this study, two new culture modes were adopted to increase the production of Coscinodiscus sp., the effect of changes in culture conditions and growth status on the hemostatic activity of diatoms was detected. To prevent Coscinodiscus sp. from sinking in culture, the suspension culture mode was realized by adding 0.5% agar. The semi-continuous high nutrient concentration culture mode increased the cell density of Coscinodiscus sp. to 11000 cells mL⁻¹ and shorten the culture cycle to 5 d. In terms of coagulation activity, the addition of frustules reduced the in vitro coagulation time by half and the activation time of coagulation by 70%. The hemolysis rate and cytotoxicity of frustules harvested in the two culture modes did not change significantly. The results showed that suspension culture mode and high nutrient concentration culture mode only changed the growth state of Coscinodiscus sp., while the hemostatic performance remained stable.