Lipidomics and spatial metabolomics reveal the heterogeneity in lipid distribution within pecan kernels

Weixia Chang; Yanyan Chen; Peisi Xie; Xin Diao; Xiaohua Yao; Jun Chang; Chengcai Zhang; Zongwei Cai

doi:10.1016/j.foodchem.2024.142368

Lipidomics and spatial metabolomics reveal the heterogeneity in lipid distribution within pecan kernels

Food Chem. 2024 Dec 4:467:142368. doi: 10.1016/j.foodchem.2024.142368. Online ahead of print.

Authors

Weixia Chang¹, Yanyan Chen¹, Peisi Xie¹, Xin Diao¹, Xiaohua Yao², Jun Chang², Chengcai Zhang³, Zongwei Cai⁴

Affiliations

¹ State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong 999077, China.
² State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding of Zhejiang Province, Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China.
³ State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding of Zhejiang Province, Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China. Electronic address: zhangchengcai-1@163.com.
⁴ State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong 999077, China; Eastern Institute of Technology, Ningbo 315100, China. Electronic address: zwcai@hkbu.edu.hk.

PMID: 39662248
DOI: 10.1016/j.foodchem.2024.142368

Abstract

Pecan (Carya illinoinensis) is a globally important nut crop, yet the processes of lipid biosynthesis and spatial lipid distribution within its embryo remain poorly understood. This study employed UHPLC-MS/MS and MALDI-MSI to profile lipids in developing pecan embryos, identifying 401 lipid molecules, including a high abundance of glycerolipids (148) and glycerophospholipids (144). Differential diacylglycerols showed gradual uptrends, highlighting their role in synthesizing glycerolipids and glycerophospholipids. Unsaturated fatty acids, especially oleic, linoleic, and linolenic acids, were enriched in triacylglycerols, diacylglycerols, phosphatidylethanolamines, and phosphatidylcholines. MALDI-MSI revealed the spatial distribution of phosphatidic acid (PA), phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylinositol (PI), suggesting heterogeneous lipid distribution within embryos. The proportion of linoleic and linolenic acids is higher in the kernel coat, whereas the proportion of oleic acid is relatively higher in the cotyledons. Differences in lipid content were also observed between the inner and outer cotyledons. This study provides the first comprehensive map of lipid distribution in pecan embryos, offering new insights into lipid metabolism regulation.

Keywords: Development; Lipidomics; Pecan; Spatial metabolomics.