3种陆生植物化感物质提取液的抑藻活性研究（摘要）

目的]研究3种陆生植物化感物质蝗取液的抑藻活性。方法]采用乙醇浸提,正己烷、乙酸乙酯、正丁醇逐级分相萃取法,对广玉兰,黄杨和龙瓜槐3种植物叶片中的化感物质进行分离提取,并测定各组分的抑藻特性。结果]广玉兰中的抑藻活性组分存在于正己烷和正丁醇相中。龙爪槐的活性组分存在于正己烷相中;黄杨的抑藻活性组分主要存在于乙酸乙酯相和水相中。除黄杨水相组分外,各活性组分在投加1d后即表现出显著抑藻活性,抑制率达50%,且抑制率随培养时间的增加而增加,对铜绿微囊藻的7d生长抑制率均达90%以上,各组分的抑藻活性在一定范围内亦随浓度的升高而增强。其中广玉兰正己烷相和正丁醇相组分在最低浓度25μg/ml时抑藻活性达96%以上,显著高于其他各组分,且能引起藻细胞膨大或表面皱缩空洞。结论]广玉兰正己烷相和正丁醇相组分对铜绿微囊藻生长的抑制活性最好,最具进一步研究的价值。

Antialgal Activities of Allelochemical Extracts from 3 Terrestrial Plant Species

Objective] The aim was to study the antialgal activities of allelochemical extracts from three terrestrial plant species.Method] The allelochemicals were extracted from the leaves of Magnolia grandiflora,Sophora japonica f.pendula and Buxus sinica （Rehd.et Wils.） Cheng by alcohol extraction,n-hexane,ethyl acetate and n-utanol phase.Furthermore antialgal activities of all components were determined.Result] The active substances of M.grandiflora mainly existed in n-hexane and n-butanol phases.The active substances of S.japonica mainly existed in n-hexane phase,while the active substances of B.sinica mainly existed in ethyl acetate and aqueous phase.All the active substances showed significant antialgal activity （50% inhibition） after culture for 1 d except aqueous phase of B.sinica.In addition,inhibition rates of the tested phases increased with the increasing of culture duration and testing concentrations.The inhibition rates were over 90% against the growth of M.aeruginosa after culture for 7 d.The n-hexane and n-butanol phases of M.grandiflora exhibited the best antialgal activity,over 96% inhibition rate at the concentration of 25 μg/ml,which was significantly higher than those of the other components,furthermore it could cause shrinkage and obvious surface inanition of Microcystis aeruginosa.Conclusion] The n-hexane and n-butanol phases of M.grandiflora have the best inhibition activities on the growth of Microcystis aeruginosa,so they are worthy of further study.