Sarpal Amarjit S, Teixeira Cláudia M L L, Silva Paulo Roque Martins, da Costa Monteiro Thays Vieira, da Silva Júlia Itacolomy, da Cunha Valnei Smarcaro, Daroda Romeu José
National Institute of Metrology, Standardization and Industrial Quality - INMETRO, Avenida Nossa Senhora das Graças 50, Xerém, Duque de Caxias, RJ, Brazil.
National Institute of Technology (INT), Rio de Janeiro, Brazil.
Appl Microbiol Biotechnol. 2016 Mar;100(5):2471-85. doi: 10.1007/s00253-015-7140-x. Epub 2015 Nov 28.
In the present investigation, the application of NMR spectroscopic techniques was extensively used with an objective to explore the biodiesel potential of biomass cultivated on a lab scale using strains of Chlorella vulgaris and Scenedesmus ecornis. The effect of variation in the composition of culturing medium on the neutral and polar lipids productivity, and fatty acid profile of solvent extracts of microalgae biomass was studied. Determination of unsaturated fatty acid composition (C18:N = 1-3, ω3 C20:5, ω3 C22:6), polyunsaturated fatty esters (PUFEs), saturated fatty acids (SFAs), unsaturated fatty acids (UFAs), free fatty acids (FFAs), and iodine value were achieved from a single (1)H NMR spectral analysis. The results were validated by (13)C NMR and GC-MS analyses. It was demonstrated that newly developed methods based on (1)H and (13)C NMR techniques are direct, rapid, and convenient for monitoring the microalgae cultivation process for enhancement of lipid productivity and their quality aspects in the solvent extracts of microalgal biomasses without any sample treatment and prior separation compared to other methods. The fatty acid composition of algae extracts was found to be similar to vegetable and fish oils, mostly rich in C16:0, C18:N (N = 0 to 3), and n-3 omega polyunsaturated fatty acids (PUFAs). The lipid content, particularly neutral lipids, as well as most of the quality parameters were found to be medium specific by both the strains. The newly developed methods based on NMR and ultrasonic procedure developed for efficient extraction of neutral lipids are cost economic and can be an effective aid for rapid screening of algae strains for modulation of lipid productivity with desired biodiesel quality and value-added products including fatty acid profile.
在本研究中，广泛应用了核磁共振光谱技术，目的是探索利用普通小球藻和无角栅藻菌株在实验室规模培养的生物质的生物柴油潜力。研究了培养基组成变化对微藻生物质溶剂提取物中中性和极性脂质生产率以及脂肪酸谱的影响。通过单（1）H核磁共振光谱分析测定了不饱和脂肪酸组成（C18:N = 1 - 3、ω3 C20:5、ω3 C22:6）、多不饱和脂肪酸酯（PUFEs）、饱和脂肪酸（SFAs）、不饱和脂肪酸（UFAs）、游离脂肪酸（FFAs）和碘值。结果通过（13）C核磁共振和气相色谱 - 质谱分析进行了验证。结果表明，与其他方法相比，基于（1）H和（13）C核磁共振技术的新开发方法直接、快速且方便，无需任何样品处理和预先分离即可监测微藻培养过程，以提高微藻生物质溶剂提取物中的脂质生产率及其质量方面。发现藻类提取物的脂肪酸组成与植物油和鱼油相似，主要富含C16:0、C18:N（N = 0至3）和n - 3ω多不饱和脂肪酸（PUFAs）。两种菌株的脂质含量，特别是中性脂质以及大多数质量参数都具有培养基特异性。基于核磁共振和超声程序新开发的用于高效提取中性脂质的方法具有成本效益，并且可以有效地辅助快速筛选藻类菌株，以调节具有所需生物柴油质量和增值产品（包括脂肪酸谱）的脂质生产率。
