Thidiazuron-induced changes in biomass parameters, total phenolic content, and antioxidant activity in callus cultures of Artemisia absinthium L.

Callus culture of Artemisia absinthium L. was established for enhanced production of phenolics and higher antioxidant activity. Callus was induced from seed-derived leaf explants, incubated on to MS media supplemented with thidiazuron (TDZ; 0.5-5.0 mg/l) either alone or in combination with α-naphthalene acetic acid (NAA; 1.0 mg/l). These callus cultures were investigated for their growth kinetics, total phenolic content, and antioxidant activity on weekly basis for a period of 49 days. Maximum dry biomass accumulation of 8.73 g/l was observed on day 42 in response to 1.0 mg/l TDZ and 1.0 mg/l NAA. Furthermore, maximum level of total phenolic content of 8.53 mg GAE/g DW and highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of 72.6% were observed in calli formed in response to 1.0 mg/l TDZ on day 42. The results showed a positive correlation of total phenolic content and DPPH radical scavenging activity in most of the callus cultures of A. absinthium L.