Lupeol increases antioxidants in Triticum aestivum to mitigate cadmium stress under in vitro conditions

Presence of heavy metals in culturing media and soil badly impact on the growth, development, and yield of plants. Availability of stress-mitigating molecules in the environment strengthens the plant to face such stresses. Lupeol has recently been investigated as a drought stress-relieving molecule in plants. In this study, lupeol was applied to plants as a heavy metal stress-mitigating agent. Triticum aestivum grown under in vitro conditions in the presence of Cadmium (Cd) salt stress and lupeol has been investigated for morphological and biochemical (enzymatic and non-enzymatic antioxidants) attributes. Heavy metal (Cd) stress (25–100 mg/L) resulted in a decrease in root length, shoot length, number of roots and dry weight in a dose-dependent manner. However, application of lupeol (0.5–2.0 mg/L) alleviated the metal stress and a significant increase in plant morphological parameters was observed. The free radical scavenging potential and antioxidative response decreased when lupeol was applied along with metal stress, as compared to the negative control. Non-enzymatic (phenolics and flavonoids) and enzymatic (superoxide dismutase and peroxidase) antioxidants levels increased in the plant under heavy metal. However, concentrations of these antioxidants significantly decreased when lupeol was applied along with the heavy metal. The study concludes that application of lupeol in the medium protects the plant from oxidative damage caused by heavy metal by increasing the antioxidants quenching the free radicals.