Comparative proteomic evaluation of silkworm (Bombyx mori) male and female pupae

Edible insects, a traditionally food in East and Southeast Asia, can be a source of sustainable protein with low environmental impact [1]. Among them, the silkworm (Bombyx mori) pupae (SWP) has been included in the list of insect species with the biggest potential to be used as food and feed in the EU even if a specific risk assessment should be performed, including the evaluation of the allergenic potential associated to entomophagy [2]. The aim of this work was to characterize the protein profile of SWP by 1D and 2D-PAGE coupled to mass spectrometry (MS) for the identification of the most abundant spots and to detect any gender-dependent differences in protein expression. Two biological replicates of SWP from each gender were reared on an artificial patented diet [3]. Protein extracts were separated by 2D-PAGE (3 technical replicates for each sample), followed by image and statistical analyses. Both most abundant and gender-dependent differentially expressed proteins were excised to be identified by MS analysis. Mean total protein content resulted to be 14.4 and 17.5 g/kg in male and female, respectively. Proteomic analysis showed three most abundant protein groups in both male and female, that are currently under identification by MS. More than 30 spots were differentially expressed between male and female SWP considering a 2-fold variation threshold, and ,among them, 28 spots were gender-specific. All these proteins are now under identification in order to evaluate gender-dependent influence on protein expression. This preliminary proteomic study could improve the state-of-the-art knowledge about edible insects in term of protein content and characterization, both for nutritional and safety evaluation purposes. [1] FAO (2013), Edible insects: future prospects for food and feed security. Rome: FAO [2] EFSA Scientific Committee (2015). EFSA Journal, 13(10): 4257 [3] CAPPELLOZZA L., et al. (2005). Applied Entomology and Zoology, 40 (3): 405-412