Studies on the Effects on Growth and Antioxidant Responses of Two Marine Microalgal Species to Uniconazole  

作　　者：MEI Xueqiao ZHENG Kang WANG Lingdong LI Yantuan 

机构地区：[1]Marine Drug and Food Institute, Ocean University of China

出　　处：《Journal of Ocean University of China》2014年第5期877-882,共6页中国海洋大学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Nos. 21071133, 51273184 and 81202399);the Program for Science and Technology of Shandong Province (2011GHY11521);the Natural Science Foundation of Qingdao City (Nos. 11-2-4-1-(9) gch), 12-1-3-52-(1)-nsh and 12-1-4-16-(7)-jch)

摘　　要：Uniconazole, as a plant growth retardant, can enhance stress tolerance in plants, possibly because of improved antioxidation defense mechanisms with higher activities of superoxide dismutase(SOD) and peroxidase(POD) enzymes that retard lipid peroxidation and membrane deterioration. These years much attention has been focused on the responses of antioxidant system in plants to uniconazole stress, but such studies on aquatic organism are very few. Moreover, no information is available on growth and antioxidant response in marine microalgae to uniconazole. In this paper, the growth and antioxidant responses of two marine microalgal species, Platymonas helgolandica and Pavlova viridis, at six uniconazole concentrations(0-15 mg L-1) were investigated. The results demonstrated that 3 mg L-1 uniconazole could increase significantly chlorophyll a and carbohydrate contents of P. helgolandica(P < 0.05). Higher concentrations(≥12 mg L-1) of uniconazole could inhibit significantly the growth, dry weight, chlorophyll-a and carbohydrate contents of P. helgolandica and P. viridis(P < 0.05). Uniconazole caused a significant increase in lipid peroxidation production(MDA) at higher concentrations(≥ 9 mg L-1). The activities of antioxidant enzymes, superoxide dismutase(SOD) and catalase(CAT) were enhanced remarkably at low concentrations of uniconazole. However, significant reduction of SOD and CAT activities was observed at higher concentrations of uniconazole.Uniconazole, as a plant growth retardant, can enhance stress tolerance in plants, possibly because of improved antioxidation defense mechanisms with higher activities of superoxide dismutase（SOD） and peroxidase（POD） enzymes that retard lipid peroxidation and membrane deterioration. These years much attention has been focused on the responses of antioxidant system in plants to uniconazole stress, but such studies on aquatic organism are very few. Moreover, no information is available on growth and antioxidant response in marine microalgae to uniconazole. In this paper, the growth and antioxidant responses of two marine microalgal species, Platymonas helgolandica and Pavlova viridis, at six uniconazole concentrations（0-15 mg L^-1） were investigated. The results demonstrated that 3 mg L^-1 uniconazole could increase significantly chlorophyll a and carbohydrate contents of P. helgolandica（P 0.05）. Higher concentrations（≥12 mg L-1） of uniconazole could inhibit significantly the growth, dry weight, chlorophyll-a and carbohydrate contents of P. helgolandica and P. viridis（P 0.05）. Uniconazole caused a significant increase in lipid peroxidation production（MDA） at higher concentrations（≥ 9 mg L^-1）. The activities of antioxidant enzymes, superoxide dismutase（SOD） and catalase（CAT） were enhanced remarkably at low concentrations of uniconazole. However, significant reduction of SOD and CAT activities was observed at higher concentrations of uniconazole.

关 键 词：catalase（CAT） lipid peroxidation Platymonas helgolandica Pavlova viridis superoxide dismutase（SOD） UNICONAZOLE 

分 类 号：Q178.53[生物学—水生生物学]