Lipid fingerprinting of yellow mealworm Tenebrio molitor by untargeted liquid chromatography-mass spectrometry

Abstract

Insects such as Tenebrio molitor have been considered an alternative source of nutrition for animals and have also been adopted as human food throughout history, especially in Asia and Africa. Lipids are the second most abundant component followed by proteins. However, studies focusing on comprehensive lipid composition analsysis of these widely reared species are limited. The untargeted lipidomic analysis of yellow mealworm larvae (T. molitor) led to the identification of several lipid molecular species from lipid classes such as: free fatty acids, sphingolipids, phospholipids, and triacylglycerols. The results revealed that polyunsaturated fatty acids (PUFAs) (45%) are the most abundant fatty acids, followed by monounsaturated fatty acids (MUFAs) (42%) and saturated fatty acids (13%). Fatty acids such as FA 18:1 and FA 18:2 are the most abundant fatty acids and are substantially enriched in other complex lipids in the form of esters. Moreover, functional lipids such as sphingomyelins, ceramides, cardiolipins, phosphatidylinositols, and phosphatidylethanolamines were characterised for the first time, with a large number of MUFAs and PUFAs as their main acyl chains. Overall, our data showed the occurrence of multiple structurally diverse lipids in T. molitor, suggesting that mealworms are not only enriched with proteins but also have several functional lipids, which are highly beneficial to human and animal health. Thus, the larvae of T. molitor could serve as a promising candidate for the development of functional food and feed products.