鼠李糖脂对硅藻生长的影响及其选择性抑藻作用

以尖刺拟菱形藻Pseudo-nitzschiapungens(PS0201-01)]、双突角毛藻(ChaetocerosDidymus)、柔弱角毛藻(Chaertocerosdebilis)、旋链角毛藻(Chaetoceroscurvisetus)和新月菱形藻(Nitzschiaclosterium)5种硅藻为研究对象,探讨了铜绿假单胞菌产鼠李糖脂类生物表面活性剂对海洋硅藻生长的影响.结果表明,当鼠李糖脂的浓度从0.5mg/L至10.0mg/L逐渐递增时,对5种硅藻的生长表现出了不同程度的抑制作用.通过各海洋硅藻脂肪酸组成的差异分析了鼠李糖脂对不同硅藻生长抑制作用具有差异的原因.结果表明,这种差异性与各海洋硅藻生物膜的脂肪酸组成不同相关,海洋硅藻的各种多不饱和脂肪酸的含量越低,相对应的96h-EC50值越低,鼠李糖脂对其生长抑制作用越强,反之亦然.进一步探讨了鼠李糖脂抑藻效果与分属不同门类的多种海洋微藻的脂肪酸组成的关系,确证了鼠李糖脂的选择性抑藻作用与不同海洋微藻生物膜的脂肪酸组成不同相关.

The influence of rhamnolioid on the growth of diatom and its selective algal growth inhibitory action

The influence of the rhamnolipid biosurfactants produced by Pseudomonas aeruginosa on the growth of marine diatom was explored by using 5 kinds of diatom: Pseudo-nitzschia pungens (PS0201-01), Chaetoceros,Didymus, Chaeroeros debilis, Chaetoceros curvisetus, Nitzschia closterium as studied objects. As the concentration of rhamnolipid increased gradually from 0.5 to 10.0mg/L, it displayed different degree of inhibitory action on the growth of 5 kinds of diatom. Through analyzing the difference of the marine diatom fatty acid composition, the cause of the different susceptibilities of the diatom to the rhamnolipid was investigated. This different character was related to the different fatty acid composition of the marine diatom biomembrane. The lower the content of polyunsaturated fatty acids (PUFAs) was, the lower the corresponding 96h-EC50 value was the same on the contrary. Further investigation of the relation between the inhibitory effect of rhamnolipid on algae of different phyla and the fatty acid composition of the algae proved firmly that the selective algal growth inhibitory action was related to the different fatty acid composition of marine microalgae biomembrane.