Lupin, a member of legume family has desirable nutritional properties; it is rich in protein and fibre; and low in carbohydrate and fat content. In addition, lupin seeds are reported to possess many nutraceutical properties such as: the ability to lower cholesterol and blood pressure, manage glucose levels and reducing obesity by lowering energy intake while increasing satiety. The production sustainability of lupin together with its unique nutritional and health-promoting properties, have made this legume a promising source of plant-based protein that can contribute towards achieving global food security.
However, the allergenicity of lupin is an emerging health concern, therefore it has been subjected to mandatory labelling on food products in Australia, New Zealand and the European Union. This emphasises the importance of identification/development of hypoallergenic lupin varieties and the necessity of developing reliable analytical methods to precisely detect and measure lupin allergens in food products.
In this research, the available allergen protein databases (AllFAM, Allergome, IUIS) were used for identification of putative cross-reactive allergens from lupin. The discovery-based tandem mass spectrometry (LC-MS/MS) were employed for studying the proteome composition of 46 narrow-leafed lupin (NLL, Lupinus angustifolius) varieties, which was followed by proteome-wide quantitation through sequential window acquisition of all theoretical fragment ions (SWATH) mass spectrometry. Subsequently, the relative abundance of the allergenic proteins was compared across these lupin lines.
Overall, the evaluation revealed substantial differences in the allergenic protein expression profiles for the examined varieties. Most of the identified putative allergens with high sequence homology with the known “Lup an 1” allergen were found to be present at lower levels in the analysed Australian and European domesticated varieties. The findings of this study can benefit the lupin breeding strategies and assist the producers to comply with food-labelling regulations for safeguarding the health of the allergic consumers.