Genetic stability and phytochemical profiling of the in vitro regenerated plants of Angelica glauca Edgew.: an endangered medicinal plant of Himalaya

The present study describes the first successful report on in vitro propagation through direct organogenesis for multiple shoot induction of Angelica glauca. Rhizomes were used as explant, and maximum shoot multiplication was observed on MS medium supplemented with 6-Benzylaminopurine 8.0 µM and Indole-3-acetic acid 0.1 µM. Roots were observed within 14 days in the MS medium enriched with 0.5 µM IAA and 0.1 µM Naphthalene acetic acid (NAA) with an average production of 4.2 roots per shoot. Rooted plantlets were successfully hardened under greenhouse conditions and subsequently established in field, with a recorded survival rate of 72% after 45 days. The total phenolic content showed significant difference (p < 0.05) between in vitro raised plants (5.87 mM AAE/ g DW) and control (2.36 mM AAE/ g DW). Antioxidant activity, calculated through two in vitro assays, i.e. 1,1-diphenyl-2 picrylhydrazyl (DPPH) radical scavenging and Ferric Reducing Antioxidant Power (FRAP) assays revealed higher antioxidant activity in in vitro grown plants in comparison to control plants. Essential oil constituent’s analysis was also carried out in control and in vitro raised plants. Thirty-one compounds were identified in the oil samples through Gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS) analysis also identified 31 compounds in the essential oil, representing 98.1–98.7% of total oil compositions. The major components of the essential oils were (Z)-ligustilide (51.1–51.5%), (Z)-butylidene phthalide (31.2–31.6%), (E)-butylidene phthalide (2.6–2.9%) and (E)-ligustilide (2.1–1.8%). Genetic stability of in vitro raised plants, evaluated using 20 Inter Simple Sequence Repeats primers, proved true to typeness of in vitro raised plants.