Unique Distribution of Diacyl-, Alkylacyl-, and Alkenylacyl-Phosphatidylcholine Species Visualized in Pork Chop Tissues by Matrix-Assisted Laser Desorption/Ionization-Mass Spectrometry Imaging

• Published in: Foods 2020-02, Vol.9 (2), p.205
• Main Authors: Enomoto, Hirofumi, Furukawa, Tomohiro, Takeda, Shiro, Hatta, Hajime, Zaima, Nobuhiro
• Format: Article
• Language: English
• Subjects: lipid distribution; liquid chromatography-tandem mass spectrometry (lc-ms/ms); mass spectrometry imaging (msi); matrix-assisted laser desorption/ionization (maldi); phosphatidylcholines; pork
• ISSN: 2304-8158; 2304-8158
• DOI: 10.3390/foods9020205

Phosphatidylcholine (PC) is the major phospholipid in meat and influences meat qualities, such as healthiness. PC is classified into three groups based on the bond at the position: Diacyl, alkylacyl, and alkenylacyl. To investigate their composition and distribution in pork tissues, including (loin) spinalis muscles, intermuscular fat, and transparent tissues, we performed matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI). Eleven diacyl-, seven alkylacyl-, and six alkenylacyl-PCs were identified using liquid chromatography (LC)-tandem MS (MS/MS) analysis. Despite many alkylacyl- and alkenylacyl-PC species sharing identical / values, we were able to visualize these PC species using MALDI-MSI. Diacyl- and alkylacyl- and/or alkenylacyl-PC species showed unique distribution patterns in the tissues, suggesting that their distribution patterns were dependent on their fatty acid compositions. PCs are a major dietary source of choline in meat, and the amount was significantly higher in the muscle tissues. Consumption of choline mitigates age-related memory decline and neurodegenerative diseases; therefore, the consumption of pork muscle tissues could help to mitigate these diseases. These results support the use of MALDI-MSI analysis for assessing the association between PC species and the quality parameters of meat.