Effects of ultrasonic wave on the growth and fatty acid composition of Isochrysis zhanjiangensis

设计了一个超声频率、超声功率和处理时间三因素四水平的正交实验 ,研究了超声波对湛江等鞭金藻的生物学效应 .实验结果表明 ,超声频率对湛江等鞭金藻的生物学效应显著 ,而超声功率和处理时间的影响相对较小 .对于提高湛江等鞭金藻生长速率常数 ,最佳超声条件为 2 0kHz ,6W ,1 0s 3次 ;对于提高其脂肪酸不饱和度和主要不饱和脂肪酸百分比 ,最佳超声条件为 2 0kHz,4～ 6W ,30s.在最佳超声条件下 ,湛江等鞭金藻生长速率常数最高可达 0 6 30d ,是对照组的 2 0 2倍 ,其脂肪酸不饱和度最高可达 79 6 % ,比对照组提高 7 8% ,其中主要不饱和脂肪酸的百分含量均得到不同程度的提高A three factors and four levels orthogonal experiment, including ultrasonic frequency, power and treatment duration, is conducted to study biological effect of ultrasonic treatment on Isochrysis zhanjiangensis . The experimental results suggest that ultrasonic frequency has significant biological effect,and ultrasonic power and treatment duration have less influence on this alga. The optimum ultrasonic conditions are 20 kHz,6 W,10 s (triplicate) for increasing the constant of growth rate of this alga, and 20 kHz,4～6 W,30 s for increasing its unsaturation degree of total fatty acids( TFA ) and the percentages of major unsaturated fatty acids. The maximum constant of growth rate of Isochrysis zhanjiangensis can be 0 630 d which is 2 02 times of that of the controls. The maximum unsaturation degree can be 79 6%which was 7 8% higher than that of the controls. The percentages of major unsaturated fatty acids in TFA can increase more or less under the optimum ultrasonic conditions.国家自然科学基金资助项目 (39870 5 6 5