Methyl jasmonate and copper activate volatiles and antioxidant mechanisms in 'Grecco a Palla' basil produced in vitro

In vitro, shoot apices cultures provide an alternative means for producing secondary metabolites of medicinal and pharmaceutical importance. In this study, the major objective was to investigate the effect of Copper (Cu) and Methyl Jasmonate elicitors on basil 'Grecco a Palla' shoot apex growth, on the volatile chemical composition, and biological and enzymatic activities. Stem apex, from seedlings grown in vitro , were used as explant for plant propagation. Murashige—Skoog medium, supplemented with five elicitors concentrations (T1: 0 µM, 0 µM; T2: 25 µM, 0 µM; T3: 0 µM, 5 µM, T4: 25 µM, 5 µM; T5: 75 µM, 5 µM de Cu and MeJa, respectively) was used for the inoculation. Cooper in combination with MeJa (T3 and T4) reduced the occurrence of oxidation (20%) and hyperhydricity (77%) in the shoot when compared to the control treatment. 25 µM Cu and 5 µM MeJa increased the antioxidant activity by 72.5% (DPPH), the enzymatic activity of Phenylalanine ammonia-lyase (PAL) by 95%, the total phenolic compounds by 33,33%, and superoxide dismutase (SOD) enzymatic activity by 37%. In the 75 µM Cu and 5 µM MeJa treatment resulted in an increase of 20% in the ascorbate peroxidase enzyme activity. Those treatments promoted a higher number of volatile compounds to T4 (20) and T5 (28), of which α-bergamotene, methyl eugenol, and linalool were found to be the majority. β -Pinene, Myrcene, γ -Cadinene, and δ -Cadinene were only identified in T5. Therefore, the above-mentioned elicitors might be used in combination with the described concentrations, in order to improve the compound synthesis and antioxidant activity.