Quantitative Determination of Fatty Acid Compositions in Edible Oils Using J -Selective 13 C QDEPT
- PDF / 602,839 Bytes
- 7 Pages / 595.276 x 790.866 pts Page_size
- 62 Downloads / 196 Views
Quantitative Determination of Fatty Acid Compositions in Edible Oils Using J-Selective 13C QDEPT Yunyan Li 1,2 & Wenping Mao 1,2 & Chaoyang Liu 3 & Xu Zhang 3 & Junfeng Wang 1,2,4 Received: 6 June 2018 / Accepted: 7 January 2019 # Springer Science+Business Media, LLC, part of Springer Nature 2019
Abstract We propose a J-selective quantitative distortionless enhancement by polarization transfer (J-selective QDEPT) 13C NMR method with enhanced sensitivity for accurate determination of the fatty acid compositions of edible oils. The J-selective QDEPT protocol is developed by targeted optimization of the known Q-DEPT+ experiment. Based on the one-bond C-H J-coupling constants (1JCH) which can be measured with the heteronuclear two-dimensional J-resolved 13C NMR spectrum, it is possible to optimize the polarization transfer delay Δ and the reading pulse angle ⊖, thus enabling the QDEPT experiment further enhancing 13C resonance signals which have narrow 1JCH ranges over the traditional untargeted Q-DEPT. For edible oil applications, it is demonstrated that this procedure brings a 2.2 enhancement factor against 1.3 of the traditional untargeted Q-DEPT compared to the standard inverse-gated 13 C experiment, even with a shorter relaxation delay for the two QDEPT experiments. Another advantage of J-selective QDEPT is that a smaller number of quantitative scans are needed to reach a uniform enhancement for different CHn (n = 1, 2, 3) groups. These features of the J-selective QDEPT are particularly attractive for batch analysis in the food industry. Keywords Quantitative 13C NMR . Sensitivity enhancement . J-selective QDEPT . Fatty acid . Edible oil
Introduction Many health risks, including prostate cancer, obesity, fatty liver, and coronary heart diseases, are correlated with unbalanced fatty acid (FA) intake (Hammad and Jones 2017; Pelser et al. 2013; Electronic supplementary material The online version of this article (https://doi.org/10.1007/s12161-019-01432-8) contains supplementary material, which is available to authorized users. * Xu Zhang [email protected] * Junfeng Wang [email protected] 1
High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, Anhui, China
2
Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences, Hefei 230031, Anhui, China
3
Wuhan Center for Magnetic Resonance, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, Hubei, China
4
Institute of Physical Science and Information Technology, Anhui University, Hefei 230031, Anhui, China
Willett 2012). Dietary modulation with emphasis on FA intake could be a therapeutic option in the prevention of various diseases. As an important part of a healthy diet, vegetable oils have been recommended due to their high contents of FAs besides the traditional FA sources, such as fish oil and algae (Orsavova et al. 2015). However, distribution and content of FAs differ in dependence on var
Data Loading...
