小珊瑚藻对赤潮异弯藻的化感效应

Allelopathic effects of Corallina pilulifera on red tide microalgae Heterosigma akashiwo.

研究了不同浓度的小珊瑚藻组织4种不同极性有机溶剂(甲醇、丙酮、乙醚、氯仿)提取物对赤潮异弯藻的生长抑制作用.结果表明:小珊瑚藻组织甲醇提取物对赤潮异弯藻的生长抑制活性最强,并且在较高浓度下能使赤潮异弯藻完全死亡,其他3种有机溶剂提取物对赤潮异弯藻的生长无明显影响.表明小珊瑚藻组织中含有的对赤潮异弯藻有抑制作用的活性物质具有较高的极性.对小珊瑚藻的甲醇提取物进行液液萃取,将其分离为石油醚相、乙酸乙酯相、正丁醇相和蒸馏水相,并对赤潮异弯藻进行生物活性检测.结果发现石油醚相和乙酸乙酯相具有较强的杀藻活性,表明脂肪酸可能是小珊瑚藻组织内抑制赤潮异弯藻生长的化感物质的重要组成成分之一.

Different concentration methanol-, acetone-, ether-, and chloroform extracts of Corallina pilulifera were used to study their growth inhibitory effects on red tide microalgae Heterosigma akashiwo. The results showed that methanol extract at relatively higher concentrations had the highest growth inhibitory activity and killed all H. akashiwo cells, while the other three kinds of organic solvent extracts had no apparent inhibitory effects, suggesting that the growth inhibitory substances in C. pilulifera had relatively high polarity. The methanol extract was partitioned to petroleum ether phase, ethyl acetate phase, butanol phase, and distilled water phase by liquid-liquid fractionation, and the bioassays on the activity of each fraction were carried out on H. akashiwo. It was found that petroleum ether phase and ethyl acetate phase had strong algicidal effects on H. akashiwo, suggesting that the fatty acids in C. pilulifera tissues might be one of the main allelochemicals.