Michele Pellegrinoa, Giovanni Venturaa,b, Cosima Damiana Calvanoa,b, Tommaso R.I. Cataldia,b

aDipartimento di Chimica, Università degli Studi di Bari Aldo Moro, 70126 Bari, Italy;
bSMART Research Center, University of Bari Aldo Moro, Bari, Italy

With the growing global population, edible insects are being proposed as alternatives to meat due to their high protein content, along with vitamins, minerals, and lipids [1]. The practice of entomophagy (i.e., eating insects) is common in Africa, Asia, and South America but remains relatively uncommon in Western countries. In addition to their use as food, edible insects are incorporated into supplements and gluten-free products, and utilized to improve the chemical, physical, and sensory properties of foodstuffs. Processing methods like pasteurization, roasting, and drying are crucial to reduce bacterial load and deactivate the insects' degradative enzymes [2]. However, these treatments can also alter nutrients. For example, heating can trigger Maillard reactions, which may involve the amine group of phosphatidylethanolamines (PEs) [3], leading to the formation of modified PEs. 

This study focuses on the lipidomic characterization of edible Acheta domestica, using high-resolution mass spectrometry (HRMS) coupled with liquid chromatography (LC). Both hydrophilic interaction liquid chromatography (HILIC) and reversed-phase liquid chromatography (RPLC) were employed with ESI-HRMS. This approach allowed for the identification of conventional phospholipid classes as well as modified PEs formed by condensation reactions between carbonyl compounds generated during heating and PEs. Notably, we identified several modified PEs, including formyl-PE (FPE), acetyl-PE (AcPE), hydroxymethylfuranylmethylene-PE (HMF-PE), and Amadori-glycated PEs (AmPE) and their isomers (e.g., LacPE). These compounds are products of lipid glycation. To better understand the interaction between the glycosidic head group and the amine functionality in PEs, we performed in-vitro reactions with a standard PE and glucose (C6H12O6) or labelled glucose (13C2C4H12O6). The identification of these modified lipid classes is very useful, as they are linked to human oxidative stress and are implicated in the pathophysiology of diseases such as Alzheimer’s and type 2 diabetes [4, 5].

Acknowledgements: This work was supported by the project 2023-UNBACLE-0241870 - Lipid7, financed by Uniba ERC SEEDS project and the project PON Ricerca e Innovazione 2014-2020- 02-G-14853-2, financed by the MIUR.

Keywords: Lipidomics, Insect, LC-MS, Maillard.

References

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