Tracking Spatial Distribution Alterations of Multiple Endogenous Molecules during Lentil Germination by MALDI Mass Spectrometry Imaging

Exploring the spatial distribution alterations of metabolites during lentil germination is essential to reveal the nutritional value, physiological function, and metabolic pathway in lentils. Hence, an effective matrix-assisted laser desorption/ ionization mass spectrometry imaging (MALDI-MSI) method was established for the first time to visualize the spatial localization changes of 53 metabolites in lentils during germination for 12-72 h. The results of MALDI-MSI analysis showed that phosphatidylinositols, phosphatidylethanolamines, phosphatidylglycerols, and phosphatidic acids were mainly located in the cotyledons of lentils throughout the germination process, while triacylglycerols, phosphatidylcholines, diacylglycerols, amino acids, choline, and spermine spread throughout the lentil tissue at the initial stage of germination and gradually presented obvious distribution characteristics in the radicle with increasing germination time. Heat map analysis was used to visualize the correlations between lipid content changes and germination time, which supported the use of germinated lentils as nutraceutical or functional food.

Automated summary

Exploring the spatial distribution alterations of metabolites during lentil germination is crucial for understanding its nutritional value, physiological function, and metabolic pathway. This study established an effective MALDI-MSI method to visualize the changes in spatial localization of 53 metabolites in lentils during germination. The results showed specific distribution patterns of different metabolites, with certain lipids mainly located in the cotyledons and others spreading throughout the lentil tissue during early germination. Heat map analysis demonstrated the correlation between lipid content changes and germination time, supporting the potential use of germinated lentils as nutraceutical or functional food.