Quantification of total fatty acids in microalgae: comparison of extraction and transesterification methods
Quantification of total fatty acids in microalgae: comparison of extraction and transesterification methods
复制标题
DOI：
10.1007/s00216-014-8155-3
复制
发表时间：
2014-11-01
影响因子：
4.3
通讯作者：
Undeland, Ingrid
中科院分区：
文献类型：
--
作者：
Cavonius, Lillie R.;Carlsson, Nils-Gunnar;Undeland, Ingrid
根据Bligh和Dyer萃取法，测定微藻的脂肪酸含量通常是用氯仿和甲醇来完成的，尽管存在更快的方法。Bligh和Dyer方法与更快的方法之间的许多比较导致了相互矛盾的数据，可能是由于使用的藻类不同以及Bligh和Dyer方法的不同版本所导致的。在这里，各种形式的直接酯交换（D-TE）和两步酯交换（2-TE），包括我们实验室开发的三个版本，与原始的Bligh和Dyer （Can J Biochem Physiol 37: 911-917, 1959）提取及其两个修改（Lee et al.）进行了比较。[J]中国生物工程学报，1996，和我们自己的酸化版本)对不同细胞壁微藻的研究：galbana等chrysis， Nannochloropsis oculata和Phaeodactylum tricornutum。采用气相色谱-质谱法对11种方法的脂肪酸提取物进行分离和定量。结果表明，与2-TE法和D-TE法相比，氯仿-甲醇法对青萼野檀和三角野檀的脂肪酸含量低估，但两者的结果相似。此外，D-TE方法比氯仿-甲醇方法更快，而且使用的化学物质毒性更小。在D-TE方法中，使用盐酸和硫酸的方法回收的脂肪酸最多，而三氟化硼的回收率略低。氯仿-甲醇法所回收的脂肪酸在质量上的主要区别在于，氯仿-甲醇法所回收的三角草中饱和脂肪酸较少。
Determination of microalgaes' fatty acid content is often done with chloroform and methanol according to the Bligh and Dyer extraction, though faster methods exist. A number of comparisons between the Bligh and Dyer and faster methods have resulted in contradicting data, possibly due to differences in algae used and the different versions of the Bligh and Dyer method applied. Here, various forms of direct-transesterification (D-TE) and two-step transesterification (2-TE), including three versions developed in our lab, are compared with the original Bligh and Dyer (Can J Biochem Physiol 37: 911-917, 1959) extraction and two modifications thereof (Lee et al. J AOAC Int 79:487-492, 1996, and our own acidified version) on microalgae with different cell walls: Isochrysis galbana, Nannochloropsis oculata, and Phaeodactylum tricornutum. In total, fatty acid extracts from 11 methods were separated and quantified by gas chromatography with mass spectrometry. Results show that, for N. oculata and P. tricornutum, methods based on chloroform-methanol underestimated the fatty acid content compared with the 2-TE and D-TE methods, which gave similar results. Moreover, D-TE methods are faster than chloroform-methanol methods and use chemicals that are less toxic. Of the D-TE methods, the ones using hydrochloric acid and sulfuric acid recovered the most fatty acids, while boron trifluoride recovered slightly less. The main qualitative difference between the fatty acids recovered was that the chloroform-methanol methods recovered less saturated fatty acids in P. tricornutum.