daptation of the in vitro Culture of Origanum majorana L. For Production of Phenolic Acids

Abstract

Improving the accumulation level of the phenolic contents using plant tissue culture technique is outstanding aim. Seedlings were cultured on Murashige and Skoog (MS) medium with 6-benzyl amino purine (BAP) for shoot micro-propagation. The multiplied shoots were rooted on MS medium with 0.1 mg/L indole acetic acid (IAA) to obtain axenic plantlets. Root tips were sub-cultured in MS liquid medium with naphthalene acetic acid (NAA) and indole butyric acid (IBA) to initiate adventitious root suspension culture. The highest biomass obtained from the experiment with NAA; 0.5 mg/L (34.4 g, fresh weight). Callus grown on media with sucrose 3%, had the heaviest fresh and dry weight but the highest phenolic acids [caffeic, rosmarinic and chlorogenic acids] accumulation was with 60 g/L sucrose (HPLC analysis). Quantification of phenolic acids content in shoots and roots of field cultivated plant, in-vitro shoots culture (BAP, 1mg/L), in-vitro roots culture (IAA, 0.1 mg/L) and four treatments of adventitious root culture (0.1 and 0.5 NAA, 0.1 and 0.5 IBA mg/L), revealed that the sum of phenolic acids content was higher in in vitro shoot and root cultures (4.27 and 3.1 mg/g, respectively), while the adventitious root culture grown on media supplemented with 0.5 mg/L NAA, resulted in the highest sum of the target phenolic acids (45.01 mg/g). Elicitation with 200 M methyl jasmonate (MJ) gave the highest callus biomass and the highest accumulation level of the phenolic acids, 105.82 fold of the field shoots contents.