对羟基苯甲酸对2种赤潮微藻生长的影响

通过测定藻细胞密度和细胞体积,观察藻细胞形态,分析藻细胞内硝酸还原酶(NR)、过氧化物酶(POD)和超氧化物歧化酶(SOD)活性以及丙二醛(MDA)含量等生理指标的变化,研究了对羟基苯甲酸对2种赤潮微藻-米氏凯伦藻和塔玛亚历山大藻生长的影响。结果表明,浓度1.6mmol/L时,对羟基苯甲酸能明显地抑制这两种微藻的生长。同时发现,添加对羟基苯甲酸的藻细胞运动能力降低,藻细胞体积减小,并出现空洞、破碎以及部分抱团现象。进一步研究发现,对羟基苯甲酸明显降低了塔玛亚历山大藻NR和SOD活性,但对POD活性无明显影响;其低浓度时能增大米氏凯伦藻NR、POD和SOD活性,高浓度时则明显降低此三种酶的活性;它显著提高了两种微藻细胞内的MDA含量。

Effects of p-hydroxybenzoic Acid on the Growth of Two Species of Red Tide Microalgae

Effects of p-hydroxybenzoic acid on the growth of Karenia mikimitoi and Alexandrium tamarense were investigated.Based on the observation of algal morphology and measurement of algal density,cell size and contents of physiological indicators including NR,POD,SOD and MDA,results showed that when the concentrations ofp-hyroxybenzoic acid was over 1.6mmo·lL-1,it had obvious inhibitory effect on the two species of microalgae.And p-hydroxybenzoic acid decreased the athletic ability of the cells and decreased the cell size of Karenia mikimitoi and Alexandrium tamarense,and caused cells into cavities and pieces and gofers on cells.The further investigation found that p-hydroxybenoic acid significant inhibited the activities of NR and SOD in the cells of Alexandrium tamarense,while had no significant effect on POD activities.Activities of NR,POD and SOD in the cells of Karenia mikimitoi increased with increasing of p-hydroxybenzoic acid concentration when it was less than 0.4mmol·L-1,while these three enzymes activities decreased significantly at higher concentration of p-hydroxybenzoic acid.p-hydroxybenzoic acid increased significantly the contents of MDA in the cells of all tested microalgae.