Tomato (Solanum Lycopersicum L.) Response to Nickel Stress: Bioavailability, Accumulation and Allergenicity

Abstract

Vegetables represent a major source of Ni exposure. Environmental contamination and cultural practices can increase Ni amount in tomato posing significant risk for human health. This work assesses the tomato (Solanum lycopersicum L.) response to Ni on the agronomic yield of fruits and the related production of allergens.Two cultivars were grown in pots amended with Ni 0, 30, 60, 120, and 300 mg kg-1, respectively. XRF and ICP-MS analyses highlighted the direct increase of fruit Ni content respect to soil Ni, maintaining a stable biomass. Leaf water content increased at Ni 300 mg kg-1. Total protein content and individual allergenic components were investigated using biochemical (RP-HPLC and N-terminal amino acid sequencing) and immunological (inhibition tests of IgE binding by SPHIAa assay on the FABER® testing system) methodologies. Ni affected the fruit tissue concentration of pathogenesis-related proteins and relevant allergens (LTP, profilin, Bet v 1-like protein and TLP). This study elucidates for the first time that tomato reacts to exogenous Ni uptaking metal while changing its allergenic profiles, with potential double increasing of exposure risks for consumers. This evidence highlighted the importance of adequate choice of low-Ni tomato cultivars and practices to avoid Ni uptake by potentially contaminated matrices.

Detection of Allergenic Proteins in Foodstuffs: Advantages of the Innovative Multiplex Allergen Microarray-Based Immunoassay Compared to Conventional Methods

“…The SPHIAa method, combined with the FABER technology, represents a forefront tool exploiting a comprehensive panel of 244 allergens ( Table 2 ), namely 122 extracts and 122 purified molecules, including all the most important allergy markers, in addition to exclusive allergens not available in other test systems [ 5 , 23 , 68 ]. For instance, this method, associated with the use of appropriate sera containing the required IgE, was exploited to perform a comparative analysis of the allergen content in tomato exposed, or not exposed, to nickel (Ni) stress [ 101 ]. In particular, the allergenic proteins LTP, profilin, Bet v 1-like protein and TLP were analyzed.…”