• Journal of Aquaculture
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• v.13 no.2
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• pp.107-117
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• 2000

Optima for temperature, salinity and light intensity for Nitzschia closterium, Chlorella salina, I내초교냔 galbana and Tetraselmis subcordiformis, which are widely used in bivalve hatcheries of Shandong Province in China, were estimated. The temperature optimum was 23 $^{\circ}C$ for N. closterium and I. galbana and 25 and 27$^{\circ}C$ for C. salina and T. subcordiformis, respectively. That for salinity was 23${\textperthousand}$ for N. closterium and T, subcordiformis, but was 33${\textperthousand}$ for C. salina and I. galbana. In general, all the four microalgae grew faster under 6,000 lux than under 4,000 lux. Growth of N. closterium was faster at $25^{\circ}C$ and dropped abruptly >$25^{\circ}C$, and that of C. salina and T. subcordiformis progressively increased upto $25^{\circ}C$ but dropped beyond 27$^{\circ}C$. T. subcordiformis was the most eurythermal among the 4 species. For mass culture of microalgae in Korea, N. closterium and C. salina are suitable during spring and autumn but C. salina and I. galbana during summer. T. subcordiformis is suitable for culture throughout the year.

• Journal of Aquaculture
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• v.11 no.2
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• pp.231-240
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• 1998

Tetraselmis is widely used as a live food because of its easy handling, high nutrient, large size and wide tolerant range of temperature and salinity. In order to find the optimum Tetraselmis species for mass culture in Korea, five species of this microalgae were examined on size, optimum culture condition ${\textperthousand}$s, $^{\circ}C.$) and nutrient composition. The results obtained were as follows: Among five species of Tetraselmis, T. sp.(Haeundae) was the largest(major axis $17.6{\pm}1.87^{\mu}$m, mean cell volume 727${\mu}$m), and T. sp. (China) the smallest (major axis $14.6{\pm}1.46^{\mu}$m, mean cell volume 625m). Tetraselmis was very eurythermal and euryhaline species. But optimum temperature and salinity for growth were 24~$30^{\circ}C.$ and 27~30${\textperthousand}$, respectively. Among five species of Tetraselmis, T. sp. (China) seemed to be the most tolerant of high temperature over $30^{\circ}C.$, and T. tetrathele of low temperature below $6^{\circ}C.$. In culture density, T. suecica showed the highest growth rate among the among the five species. The cell density of this microalgae attained to $141{\times}10^4$cells/ml at $24^{\circ}C.$ and 30${\textperthousand}$ within 7 days. In chemical composition, crude protein amount was the highest in T. suecica (44.50%), and crude lipid amount it T. sp. (Haeundae, 7.13%). Total essential amino acid amount was the highest in T. sp. (Haeundae, 50.4%) and total polyunsaturated amount in T. sp. (China, 11.7%) The results on growth and chemical composition of five species of Tetraselmis indicated that T. suecica seemed to be the most suitable species for mass culture in Korea.