Algae. 2007; 22(3): 235-240.
Nutrient Uptake and Growth Kinetics of Chattonella antiqua (Hada) Ono (Raphidophyceae) Isolated from Korea
Kyung Suk Seo1* and Chang Kyu Lee2
1Resources Development Technology Team, KIMST, 275-6 Yangjae-Dong, Seocho-Ku, Seoul 137-941, Korea
2Marine Ecology Research Team, NFRDI, 408-1 Sirang-Ri, Gijang-Eup, Gijang-Gun, Busan 619-902, Korea
ABSTRACT
The red tide-causing flagellate Chattonella antiqua can cause mass fish kills by their clogging in fish gills. This study examined the nutrient requirements of C. antiqua isolated from Korea. C. antiqua displayed maximum growth at the day five, followed by a decrease in cell density. Nitrate and nitrite were the preferred nitrogen sources, along with adenosine diphosphate for phosphorus compounds. In medium that contained ammonium, a significant decrease in cell density was observed. Half-saturation constants, Ks, calculated from the maximum growth rate were 4.94 μM for NO3 and 0.79 μM for PO4. The growth of C. antiqua was not within the function of the N:P ratio (R2 = 0.29). With an N:P ratio as low as 10, the increase in cell density was apparent, with a higher division rate. At levels above 50 μM of NaNO3 or 8 μM of NaH2PO4, the growth rates were somewhat decreased. Phosphate was the limiting factor for C. antiqua growth since the starvation of phosphate had brought about a rapid decrease in cell density in semi-continuous culture. Studies about the temporal modification of the efficiency of nitrate or phosphate uptake may be necessary to explain the bloom dynamics of C. antiqua.
Keywords :
Chattonella antiqua, N:P ratio, nutrition, Raphidophyceae, red tide
