Enhancing bioactive potential by growth regulators in callus of Mentha longifolia L. leaves for anti-inflammatory and analgesic activities

Mentha longifolia L., popularly known as Mint, is a medicinal herb against inflammation and analgesic pains caused by venom of snakes and scorpions. Its leaves are commonly used by nomads of Ahaggar to treat external wounds. Unfortunately, this medicinal plant is less accessible in its natural zone. Hence, here, we propose a biotechnological approach to induce callus yielding the same effects. Callus was induced from young leaves cultivated on modified Murashige and Skoog solid medium supplemented with 30 g L-1 sucrose, 100 mg glutamine and growth regulators under dark conditions. Aqueous and C-glycoside extracts of plant and callus, respectively were prepared and analyzed by HPLC-DAD/LC-ESI-MS. The study of acute toxicity at 2000 mg kg-1 followed by the anti-inflammatory activity assessment using carrageenan-induced paw edema and the analgesic activity of acetic acid induced writhing were performed on mice. Compared to the control, the trials showed 79% higher rate of friable callus induced on 2,4-D and BAP. No mortality or signs of toxicity were observed in mice. Unexpected higher anti-inflammatory and analgesic activities by callus extracts can be attributed to their phenolic composition