H NMR多重抑制方法用于快速检测和定量支环烯结构的基和脂肪酸,无论是天然的还是在严重加热过程中产生的
Bárbara Nieva-Echevarria1, Ainhoa Ruiz-Aracama1
1Food Technology, Faculty of Pharmacy, Lascaray Research Center, University of the Basque Country (UPV/EHU). Paseo de la Universidad n° 7, 01006 Vitoria-Gasteiz, Spain.
Food research international (Ottawa, Ont.)
|November 21, 2025
概括
这项研究使用核磁共振 (NMR) 来检测食用油中的环烯脂肪酸 (AG/FA-3C). 该方法可以识别天然化合物和经热修饰的脂肪酸,区分油的来源和加工方法.
科学领域:
- 分析化学 分析化学
- 食品化学 食品化学
- 利皮多米克 (Lipidomics) 是一种消化剂.
背景情况:
- 含有环素的基/脂肪酸 (AG/FA-3C) 是食用油中罕见的脂质成分.
- 它们的存在和来源 (自然或热诱导) 在商业油中没有很好的特征.
- 需要先进的光谱技术来检测和量化它们.
研究的目的:
- 为了证明H核磁共振 (NMR) 多重抑制在食用油中检测和定量AG/FA-3C的实用性.
- 调查各种处女和精炼食用油中天然和热修饰的AG/FA-3C的存在情况.
- 探索H NMR在确定食用油的植物起源和加工状态方面的潜力.
主要方法:
- 获取和分析来自13种原始和精炼食用油的H NMR光谱.
- 专注于H NMR光谱的上方区域,以检测高度屏蔽的质子信号.
- 检测到的AG/FA-3C信号的量化和与油性质的相关性.
主要成果:
- 在食用油中成功检测和量化了以前未被描述的AG/FA-3C信号1H NMR谱.
- 识别了特定的信号 (例如,0.33 ppm的四倍),表明天然环酸脂肪酸,如乳酸和二酸,有助于识别大麻和棉油.
- 观察到精炼油中热修饰的多不和脂肪酸的独特信号模式,在烯酸和烯酸热降解之间存在差异.
- 根据HNMR光谱配置文件,证明能够区分原始和精制的多不和油.
结论:
- 1H NMR多重抑制是一种简单,快速和有效的方法,用于在没有样品预处理的情况下在食用油中分析AG/FA-3C.
- 该技术为食用油的组成提供了宝贵的见解,包括罕见的脂质成分.
- 对高原地区的H NMR分析可以作为植物起源的标记,以及区分处女和精炼食用油的工具.
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