氮、磷营养盐对底栖硅藻的生长及生化组成影响

目的:研究了从福建连江海域分离得到的一株野生底栖硅藻(Nitzschia.constricta)的生长和生理特性.方法:测定了在不同氮磷浓度条件下比增长速率、色素,以及不同时期底栖硅藻蛋白和胞外多糖的积累情况.结果:当硝酸氮浓度为900mg/l时,获得最大比增长速率0.21和叶绿素a含量4.31mg/l、类胡萝卜素含量3.44mg/l、胞外多糖产率90.57μg/ml.当氮浓度为75mg/l时,在第10d得到最大蛋白产率28.90μg/ml.当磷浓度为4.4mg/l时,可得到最大比增长速率0.13、叶绿素a含量3.42mg/l、类胡萝卜素2.82mg/l、蛋白含量23.16μg/ml,无磷培养基中第5d的胞外多糖产率最高13.51μg/ml.结论:氮磷营养盐浓度的增加促进了此种底栖硅藻的生长,但不一定会促进蛋白及胞外多糖的产生.

Effects of Nitrate and Phosphate on Growth and Biochemical Composition of Benthic Diatom

Objective:The growth and physiological parameters of the benthic diatom(Nitzschia.constricta)isolated from Lianjiang maritime space in Fujian were studied.Method: The pigments,growth rate, protein and exopolysaecharide yield were evaluated at several nitrogen and phosphorus levels on different days.Result: When the nitrate concentration is 900mg/l, the highest growth rate 0.21, chlorophylla 4.31mg/l and carotenoid 3.44mg/l,and the production of exopolysaeeharide 90.57μg/ml were obtained.While the most protein content 28.90μg/ml was obtained on the 10th day under the nitrogen concentration 75mg/l.When the phosphorus concentration is 4.4mg/ml , the highest growth rate 0.13, chlorophylla 3.42mg/l, carotenoid 2.82mg/l and the very protein content 23.16μg/ml can be acquired.However the most exopolysaccharide yield was attained to 13.51μg/ml at non -phosphorus media on the 5th day.Conclusion: The in-creasing nitrogen and phosphorus concentration can elevate the specific growth rate and pigments of the benthic diatom(Nitzschia, constric-ta) ,but will not be sure to promote the protein and exopolysaccharide yield.