Modulation of arylnaphthalene lignan accumulation in Linum alpinum in vitro root cultures by methyl jasmonate

Linum alpinum L. is a promising source of arylnaphthalene lignans, including justicidin B (JB). In vitro root cultures (RC) of L. alpinum were investigated for JB accumulation and its modulation by methyl jasmonate (MeJA). JB content was quantified by LC-HRESI-MS over a 30-day cultivation period. The modulatory effect of MeJA was evaluated after the 5 th day of application at three different concentrations. Time-dependent increase in JB accumulation was observed, rising from 69.95 ng/mg DW on day 5 to 118.66 ng/mg DW on day 30. MeJA treatment significantly influenced JB accumulation in a non-linear manner, with the highest JB content observed at 100 µM MeJA (146.97 ng/mg DW), corresponding to a 23.8% increase compared with the untreated control, while higher concentrations resulted in no further enhancement in JB levels. These findings demonstrate that both cultivation duration and elicitor concentration critically affect JB biosynthesis in L. alpinum RC and highlight the species-specific nature of MeJA-mediated regulation.