Abstract:

To achieve an optimal preservation and protection of free-living conchocelis of Porphyra yezoensis with excellent characters, the preserving conditions including temperature, light intensity and nutrition were studied. Results showed that temperature, light intensity and nutrition were all important factors affecting preservation of free-living conchocelis of Porphyra yezoensis and the safe preservation period in liquid medium supplemented with enriched seawater supplement (ESS) nutrients was over 40 days under the illumination level of 300 lx at 5 ℃ or10 ℃, with a survival rate of 90%, which was higher than that under the illumination level of 1000lx or 1500 lx at 20 ℃. Frequent alternation of the supplemented liquid medium was required for higher survival rate of the conchocelis preserved at higher temperature. In the preservation of the conchocelis encapsulated into beads made from 20% sodium alginate in its suspension at － 20 ℃, a close relationship between survival rate and water content in the beads was observed and longer dehydration time corresponding to lower water content in sodium alginate beads resulted in higher survival rate of the conchocelis.

Key words: Porphyra yezoensis, free-living conchocelis, preservation in liquid medium, encapsulation