Induction of Secondary Metabolites Contents and Antioxidant Capacity of Teucrium polium Callus under Treatment with Naphthalene Acetic Acid, Benzylaminopurine, and Methyl Jasmonate

One of the most important factors for the preservation of plants, medicinal plants in particular, is the use of biotechnological methods for increasing the production of secondary metabolites. This study was performed with the aims of evaluating and enhancing the secondary metabolites contents of Teucrium polium under in vitro culture by application of methyl jasmonate as elicitor. For callus induction, immature leaf explants were obtained from the plants grown under hydroponic condition and were cultured on MS medium supplied with various concentrations of Benzylaminopurine (BAP) (0, 0.5, 1, and 1.5 mg/L) in combination with Naphthalene acetic acid (NAA) (0, 0.5, and 1 mg/L). Regarding the highest percentage of callus induction frequency and mean of calli dry weight, the selected cultures were treated with methyl jasmonate (50, 100, and 200 μM). The content of different groups of phenolic compounds and antioxidant capacity were evaluated. The highest percentage of callus induction (100%) was achieved in the medium supplemented by BAP individually as well as in combination with NAA. The maximum fresh and dry weights of calli were achieved at 1.5 mg/L BAP + 0.5 mg/L NAA, 1.5 mg/L BAP, and 1 mg/L BAP. The calli treated with 50 μM methyl jasmonate yielded the maximum contents of phenolic compounds, flavonoids, flavones, O-diphenol, phenolic acids, and rosmarinic acid that differed significantly from calli obtained from other methyl jasmonate concentrations. The highest antioxidant activity with IC50 of 2.066 ± 0.24 µg/mL using DPPH assay, and 383.79 ± 33.61 mg Fe+ 100g-1 DW using FRAP were in 50 μM methyl jasmonate and 1.5 mg/L BAP + 0.5 mg/L NAA treatment. Based on the results, methyl jasmonate in optimal concentration can play a promotive role in increasing the effective pharmacological compounds of T. polium and can be considered as a stimulus for the synthesis of phenolic compounds and further increase of the antioxidant power in callus.