In vitro bioaccessibility of Cd, Cu, Fe and Zn in basil (Ocimum Basilicum L. Grecco a palla) after cadmium intoxication

Cadmium is a toxic element which can be accumulated in the edible parts of plants compromising an entire food chain with serious damage to the living organisms, presenting synergistic and antagonistic effects with the elemental bioaccessibility. In this work, a simulated gastrointestinal digestion was performed to assess the in vitro bioaccessibility of Cd, Cu, Fe and Zn in basil samples after Cd intoxication. The hydroponic cultivation was made in a Hoagland solution at different concentrations (0, 1.5 and 3.0 µmol L-1). Elemental concentration was achieved using a microwave-assisted acid digestion after the growing up of the plants in vermiculite pots by 15 days. The in vitro gastrointestinal procedure was applied in fresh and lyophilized leaves followed by a clean-up step in a sonoreactor cup horn using 1 mL of the extract, 100 µL of HNO3 and 500 µL of H2O2 by 5 minutes. The results showed that Cd bioaccessibility was statistically different at 95% confidence level (p < 0.05) for the lyophilized and fresh leaves samples. The in vitro bioaccessibility increased with concentration in the contamination treatment. Moreover, a high positive correlation was observed between Cd-Fe and Cu-Zn, and a negative correlation between Cd-Zn and Fe-Zn in lyophilized and fresh leaves, respectively, suggesting that the absorption of essential elements was affected by Cd.