Abstract
An increase in atmospheric CO2 levels has been observed since the beginning of the industrial era. This increase in atmospheric CO2 has been described as a fertilising agent for many plant species, leading to an alteration in their nutritional quality. Indeed, a reduction in protein and mineral content has been observed in many plants grown in a CO2-enriched atmosphere.These variations in the composition of nutrients present in plants can lead to the development of metabolic disorders and the disruption of antioxidant and anti-inflammatory defences, which can lead to an increase in the incidence of non-communicable diseases (NCDs) such as ‘metabolic syndrome’. The aim of this thesis work is to assess the effect of atmospheric CO2 enrichment on the nutritional-health quality of tomatoes (Solanum lycopersicum L.) using two types of tomato: MicroTom, a dwarf variety that has been studied extensively because it is used as a model plant, and large-fruited tomatoes represented by the parents of the MAGIC population (which represents the genetic diversity of cultivated tomatoes). By measuring macronutrients such as sugars, lipids and proteins, followed by quantifying micronutrients such as carotenoids and minerals, we were able to establish a complete nutritional profile. An assessment of the antioxidant and anti-inflammatory activity of tomato extracts was also carried out. These analyses enabled us to show, for the MicroTom model, that atmospheric CO2 enrichment had a negative impact on mineral and protein composition, accompanied by an accumulation of sugars and a change in bioactive compounds.The study of antioxidant activity in this model revealed an alteration that can be explained by the interaction between culture conditions and atmospheric CO2 enrichment, while anti-inflammatory activity appears to be unchanged. Comparable results were obtained with the MAGIC model, validating that increasing atmospheric CO2 has no negative effect on antioxidant and anti-inflammatory defences. Taken together, these observations have enabled us to make the link between atmospheric CO2 enrichment and the nutritional and human health aspects, and provide a basis for future research in this field.