An investigation on micropropagation, rosmarinic acid and essential oil content of Thymus leucotricus Hal. (Lamiaceae)

The aim of this study was to examine the effect of different concentrations of plant growth regulators, phenylalanine, tyrosine and N-acetylcystein, sucrose on growth, rosmarinic acid and essential oil contents in vitro grown Thymus leucotrichus Hal. Seeds were planted in 4 different media and that the MS medium (56.66 ± 6.67%) was the most effective. In the BBD studies performed, IBA (0,5mg /L) was identified as the most effective auxine when the most effective cytokinins were identified as 1 mg/L KIN and 2 mg/L 2iP. The highest content of rosmarinic acid in the seedlings grown in the BBD treatment was observed at 0.1 mg/L NAA group with value of 16.18 ± 1.2 mg/g a dry weight. As a result of BBD applications, the highest thymol content was observed at 0.1 mg / L IAA applications with 69.26%, the highest carvacrol content was found in the 0.1 mg/L TDZ group with 12.53% value. In the second step of the study, phenyl alanine, tyrosine and N-acetylcysteine were added at concentrations of 10, 50 and 100 mg/L separately to the control medium and effects on growth/development, rosmarinic acid and essential oil amounts were observed. It was determined that 10 mg/L NAC application was the most effective at fresh (212 mg) and dry (25.3 mg) weight parameters, while the highest shoot length was observed at 10 mg/L phenylalanine application (40.13 mm). Furthermore, among these experiments, the most effective application for rosmarinic acid production was 10 mg/L NAC (16.28 mg/g dry weight). In the sucrose experiment % 3 sucrose was the most effective application to grow, while the most rosmarinic acid content was observed in 4% sucrose assay.