Isolation of Protoplasts from Undaria pinnatifida by Alginate Lyase Digestion

摘要

The aim of this study is to isolate protoplasts from Undaria pinnatifida. Protoplasts of the alga were isolated enz-ymatically by using alginate lyase, which was prepared by fermenting culture of a strain Vibrio sp. 510. Monofacterial method was applied for optimizing digestion condition. The optimum condition for protoplast preparation is enzymatic digestion at 28℃ for 2 h using alginate lyase at the concentration of 213.36 U (8 mL) every 0.5 g fresh thalline with NaCl 50 and at the shaking speed of 150 r min~(-1) during digestion. The protoplast yield can reach 2.62 +- 0.09 million per 0.5 g fresh leave under the optimum condition. The enzyme activity is inhibited by Ca~(2+) and slightly enhanced by Fe~(2+) and Mn~(2+) at concentrations of 0.05, 0.08 and 0.10 mol L~(-1).