溢油胁迫下海洋微藻脂肪酸合成过程中碳稳定同位素分馏效应

Carbon stable isotopic fractionation associated with biosynthesis of fatty acids by marine microalgae under the stress of oil spills

摘要: 为了研究溢油对海洋生态系统中海洋微藻生长的影响,本文探讨了在不同含量燃料油180号水溶性成分(WAF)胁迫下纤细角毛藻脂肪酸碳稳定同位素比值(13C)的变化.结果表明,在燃料油WAF胁迫下,微藻生长过程中脂肪酸合成速率均受到不同程度的影响,尤其是不饱和脂肪酸16:1和18:4的13C值与油浓度(WAF)成大致的线性关系,这说明燃料油的毒害作用不仅使海洋微藻类不饱和脂肪酸合成过程受到影响,同时引起脂肪酸合成过程发生碳稳定同位素分馏效应.因此,部分不饱和脂肪酸如16:1等可作为溢油对海洋微藻类胁迫程度评价的生物标志物.

Abstract: In order to realize the effects of oil spill on marine microalgae growth, we studied the carbon stable isotope composition (13C) of Chaetoceros gracilis under the stress of different content of water accommodated fraction (WAF) of No.180 fuel oil. The result shows that the rate of fatty acid synthesis are affected by different degree of the stress of WAF in the process of microalgae growth, especially there are approximately linear relationships between the 13C values of unsaturated fatty acids (16:1 and 18:4) and WAF, which may result from the kinetic stable isotope fractionation effect. Therefore parts of unsaturated fatty acids such as 16:1 may be used as an alternative biomarker for estimating the pollution degree of oil spills.