Establishing a simple selection method of high hypericin-producing adventitious root lines from leaf explants of Hypericum perforatum var. Topaz

Hundreds of adventitious root lines from Hypericum perforatum L. were examined for their hypericin content in order to establish a system for studying the production of hypericin in adventitious root lines. The effects of the medium consistency (solid and liquid) and the effects of three different auxins (Indole-3-butyric acid (IBA), Indole-3-acetic acid (IAA), and 1-Naphthaleneacetic acid (NAA)) on the induction of adventitious roots in leaf explants were studied. In a half-strength MS liquid medium with 2 mg/L IBA concentration, adventitious roots developed from H. perforatum leaves, whereas NAA and IAA caused callus-like and low branch roots. HPLC-UV was used to profile hypericin content variations in 100 H. perforatum adventitious root lines. Hierarchical component analysis (HCA) was used for selecting elite lines. After cluster analysis and selecting high-performance lines in terms of hypericin, five elite lines were chosen and the amount of hypericin production, as well as the phenol and flavonoid content, was analysed.

Automated summary

The study aimed to establish a system for studying the production of hypericin in adventitious root lines of Hypericum perforatum L. Several factors including medium consistency and auxin type were investigated for their effects on the induction of adventitious roots from leaf explants. It was found that a half-strength MS liquid medium with 2 mg/L of IBA concentration was optimal for adventitious root development, while NAA and IAA resulted in callus-like structures and low branch roots. HPLC-UV analysis was employed to assess hypericin content variations in 100 adventitious root lines, and five elite lines with high hypericin production were identified.