Copper sulfate and Cobalt chloride effect on total phenolics accumulation and antioxidant activity of Artemisia annua L. callus cultures

Abstract

This study was conducted to investigate the influence of Copper sulfate (CuSO4) and Cobalt chloride (CoCl2) on callus biomass production, total phenolics accumulation and antioxidant activity of Artemisia annua. The in vitro leaf explants were cultured on Murashige and Skoog (MS) medium contained 1 mg/l α-naphthalene acetic acid (NAA) and 0.5 mg/l 6-benzyl adenine (BA) for callus induction. CuSO4 and CoCl2 were added separately in four concentrations (1, 2, 5 and 10 mg/l) to MS medium. CuSO4 at 2 mg/l was the most appropriate level for callus fresh and dry weights which recorded 1.29 g/explant and 0.122 g/explant, respectively. Application of CoCl2 at different levels showed a positive impact on the growth of callus. Herein, the highest callus fresh weight (1.44 g/explant) and dry weight (0.139 g/explant) were achieved by 2 mg/l CoCl2, when compared with control (0.97 g/explant for fresh weight and 0.092 g/explant for dry weight). Elicitation with CuSO4 at 2 mg/l recorded the highest total phenolic production (8.75 mg/g dry weight (DW)). However, the highest significant percentage of antioxidant activity (90.85%) was recorded for 5 mg/l CuSO4-elicited culture. For CoCl2, the highest significant values of total phenolic content (8.40 mg/g DW) and antioxidant activity (91.46 %) were achieved by 2 mg/l CoCl2 enriched medium compared to control (6.66 mg/g DW and 90.68%, respectively). The current study revealed the possibility of using callus cultures of A. annua as a promising tool for the in vitro production of phytochemicals.