1 Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Gif-sur-Yvette cedex, France.
2 Laboratoire de Chimie Physique (LCP), CNRS, Université Paris-Sud, Orsay cedex, France.
Appl Spectrosc. 2017 Oct;71(10):2344-2352. doi: 10.1177/0003702817709459. Epub 2017 May 30.
There is a growing interest worldwide for the production of renewable oil without mobilizing agriculture lands; fast and reliable methods are needed to identify highly oleaginous microorganisms of potential industrial interest. The aim of this study was to demonstrate the relevance of attenuated total reflection (ATR) spectroscopy to achieve this goal. To do so, the total lipid content of lyophilized samples of five Streptomyces strains with varying lipid content was assessed with two classical quantitative but time-consuming methods, gas chromatography-mass spectrometry (GC-MS) and ATR Fourier transform infrared (ATR FT-IR) spectroscopy in transmission mode with KBr pellets and the fast ATR method, often questioned for its lack of reliability. A linear correlation between these three methods was demonstrated allowing the establishment of equations to convert ATR values expressed as CO/amide I ratio, into micrograms of lipid per milligram of biomass. The ATR method proved to be as reliable and quantitative as the classical GC-MS and FT-IR in transmission mode methods but faster and more reproducible than the latter since it involves far less manipulation for sample preparation than the two others. Attenuated total reflection could be regarded as an efficient fast screening method to identify natural or genetically modified oleaginous microorganisms by the scientific community working in the field of bio-lipids.
全球范围内人们对于不占用耕地生产可再生油脂的兴趣日益浓厚;因此需要快速可靠的方法来鉴定具有潜在工业价值的高油脂微生物。本研究旨在展示衰减全反射(ATR)光谱在实现这一目标中的相关性。为此,使用两种经典的定量但耗时的方法,即气相色谱-质谱(GC-MS)和 ATR 傅里叶变换红外(ATR FT-IR)光谱法以 KBr 压片的透射模式,以及经常因其可靠性受到质疑的快速 ATR 方法,对具有不同脂质含量的五种链霉菌菌株的冻干样品的总脂质含量进行了评估。这三种方法之间存在线性相关性,这证明可以建立方程将 ATR 值表示为 CO/酰胺 I 比,转换为每毫克生物质的脂质微克数。ATR 方法被证明与经典的 GC-MS 和 FT-IR 透射模式方法一样可靠和定量,但比后两者更快且更可重现,因为它在样品制备方面比后两者涉及的操作要少得多。衰减全反射法可被视为鉴定天然或基因改造的油脂微生物的一种有效快速筛选方法,适用于生物油脂领域的科研人员。