Abstract
In this study, we investigated the effect of Zincum Metallicum (ZM) on zinc (Zn) toxicity in the plant species Lepidium sativum. We focused on growth, Zn uptake and numerous biochemical parameters. Seedlings were hydroponically subjected during 7 days to 0.05, 500, 1000, 1500 and 2000 µM Zn2+, in the absence or presence of 15ch or 9ch ZM. In the absence of ZM, Zn induced negative effect on growth especially at the dose of 2mM. Zn induced also chlorosis, reduced total chlorophyll and/or carotenoid content and increased the level of malondialdehyde (MDA). Under Zn-toxicity (500, 1000 and 1500 µM), the superoxide dismutase (SOD), catalase (CAT), gaiacol peroxidase (GPX) and glutathione reductase (GR) activities were increased and/or unaltered, while at 2000 µM Zn affected the activity of these enzymes. At the highest Zn level (2 mM), proline and total polyphenols and flavonoids contents were markedly induced in leaves and roots of L. sativum. Additionally, the supply of ZM in the nutrient medium considerably ameliorated the plant growth, photosynthetic pigments and the studied non-enzymatic antioxidant molecules and enzymatic activities against Zn induced-oxidative stress. Our data suggest that the potential homeopathy properties of ZM may be efficiently involved in the restriction of Zn-induced oxidative damages, by lowering Zn accumulation and translocation in the leaves and roots of Lepidium sativum.