海带中抑藻活性化合物的分离及抑藻活性分析

以2000 g海带为原料、米氏凯伦藻为测试微藻,采用甲醇浸提、液液萃取、硅胶柱层析、Seph-adax LH-20凝胶柱层析和硅胶薄层层析等分离方法,纯化可能具有抑藻活性的化合物,制备到5个薄层纯样品,B21(1.39 g)、B131(0.51 g)、B132(0.48 g)、C211(0.016 g)和C212(0....

Isolation,purification and analysis of antialgal activities of antialgal com-pounds from Laminaria japonica

Using 2 000 g kelp as raw material and Karenia mikimotoi as the test microalgae, methanol extraction, liquid-liquid extraction, silica gel column chromatography, sephadax LH-20 gel column chromatography and silica gel thin layer chromatography are used to purify compounds that might inhibit algal activity. Five samples with thin layer purity, B₂₁ (1.39 g), B₁₃₁ (0.51 g), B₁₃₂ (0.48 g), C₂₁₁ (0.016 g) and C₂₁₂ (0.020 g), are prepared. Structural identification shows that B₂₁, B₁₃₁, B₁₃₂, C₂₁₁ and C₂₁₂ are 7-hydroxyheptanic acid, tetradecanoic acid, hexadecanoic acid, octadecanoic acid, and oleic acid, respectively. They are isolated from Laminaria japonica for the first time. The results show that these five compounds have selective inhibition effects on the growth of six species of red tide microalgae (Alexandrium tamarense, Amphidinium carterae, Heterosigma akashiwo, Karenia mikimotoi, Phaeocystis globsa, and Skeletonema costatum). Among them, 7-hydroxyheptanoic acid has a wide range of antialgal activities. Except for Alexandrium tamarense, at the concentration of 50 μg/mL, the growth inhibition of 7-hydroxyheptanic acid against the other five species of red tide microalgae is close to that of copper sulfate and potassium dichromate, and the growth inhibition is more than 71% (the 4th day). Tetradecanoic acid also shows obvious inhibition on the growth of Amphidinium carterae, Karenia mikimotoi, and Skeletonema costatum. On 4th day, the growth inhibition of tetradecanoic acid for the three species of red tide microalgae is more than 57%. Furthermore, EC_{50?96 h} values of 7-hydroxyheptanic acid, tetradecanoic acid, hexadecanoic acid, and octadecanoic acid for Amphidinium carterae, Heterosigma akashiwo, Karenia mikimotoi, Phaeocystis globsa, and Skeletonema costatum are obtained for the first time, respectively. EC_{50?96 h} value of 7-hydroxyheptanic acid for Alexandrium tamarense is also determined for the first time. It is found that 7-hydroxyheptanic acid and tetradecanoic acid has the advantage of inhibiting Amphidinium carterae.