Department of Bioorganic Chemistry, Leibniz Institute of Plant Biochemistry, Weinberg 3, 06120 Halle/Saale, Germany.
Department of Molecular Genetics, Leibniz Institute of Plant Genetics and Crop Plant Research, Corrensstraße 3, 06466 Seeland, Germany.
Molecules. 2020 Nov 4;25(21):5125. doi: 10.3390/molecules25215125.
H-NMR is a very reproducible spectroscopic method and, therefore, a powerful tool for the metabolomic analysis of biological samples. However, due to the high complexity of natural samples, such as plant extracts, the evaluation of spectra is difficult because of signal overlap. The new NMR "Pure Shift" methods improve spectral resolution by suppressing homonuclear coupling and turning multiplets into singlets. The PSYCHE (Pure Shift yielded by Chirp excitation) and the Zangger-Sterk pulse sequence were tested. The parameters of the more suitable PSYCHE experiment were optimized, and the extracts of 21 species were measured. Different evaluation criteria were used to compare the suitability of the PSYCHE experiment with conventional H-NMR. The relationship between the integral of a signal and the related bin value established by linear regression demonstrates an equal representation of the integrals in binned PSYCHE spectra compared to conventional H-NMR. Using multivariate data analysis based on both techniques reveals comparable results. The obtained data demonstrate that Pure Shift spectra can support the evaluation of conventional H-NMR experiments.
NMR 是一种非常重现性的光谱方法，因此是生物样品代谢组学分析的有力工具。然而，由于天然样品（如植物提取物）的高度复杂性，由于信号重叠，评估光谱是困难的。新的 NMR“纯位移”方法通过抑制同核耦合并将多重峰转化为单峰来提高光谱分辨率。测试了 PSYCHE（通过啁啾激发产生的纯位移）和 Zangger-Sterk 脉冲序列。优化了更适合 PSYCHE 实验的参数，并测量了 21 种提取物。使用不同的评估标准比较了 PSYCHE 实验与常规 H-NMR 的适用性。通过线性回归建立的信号积分与相关-bin 值之间的关系表明，与常规 H-NMR 相比，在分箱 PSYCHE 光谱中积分的表示是相等的。基于这两种技术的多元数据分析揭示了可比的结果。所获得的数据表明，纯位移谱可以支持常规 H-NMR 实验的评估。
