Graphene-copper nanocomposites improve fruit quality and the content of bioactive compounds in tomato

Tomato fruits are an important source of bioactive compounds that can positively influence human health, so their consumption is very important in the human diet. Hence, developing technologies and strategies to improve the content of bioactive compounds in tomato fruits becomes essential. The objective of this study was to determine the effect of graphene-Cu hybrid nanocomposites on the quality of tomato fruits and their content of bioactive compounds. For this, the application to the soil of Graphene-Cu hybrid nanocomposite (GCHN), only functionalized graphene nanoplatelets (FGNP), and a control (T0) were evaluated. The results showed that the application of GCHN increased the firmness of tomato fruits by 12.6%. Furthermore, it was observed that the nanocomposites increased the carotenoid content, GCHN increased the lycopene content by 18.6%, and the β-carotene content by 95.2%. The glutathione content also increased by the application of GCHN, 19.3% more than T0. No effect was observed for GCHN in the content of phenols and flavonoids; however, FGNP decreased the flavonoids content by 11.1% compared to T0. The antioxidant activity of the lipophilic compounds was increased by GCHN up to 14.8%, while the total antioxidant activity was increased by approximately 6.5%. The content of proline and total amino acids was increased only by FGNP. The application of Graphene-Cu hybrid nanocomposites is effective in increasing the content of bioactive compounds in tomato fruits, so it can be a useful tool to improve the quality of these fruits.