Effect of exogenous methyl jasmonate on in vitro propagation, metabolic profiling and proximadiol production from Cymbopogon schoenanthus subsp. proximus

In this study, the effect of methyl jasmonate (MeJA) incorporation on in vitro propagation, metabolic profiling, and production of the bioactive compound, proximadiol, in the medicinally important herb Cymbopogon schoenanthus subsp. proximus has been investigated. The propagation approaches involved both somatic embryogenesis and direct organogenesis. All studied concentrations (10–400 µM) have significantly improved somatic embryogenesis at different developmental stages, as indicated by higher numbers of somatic and mature embryos as well as the embryogenic shoots. In contrast, the studied concentrations have negatively affected organogenic shoot and root regeneration. Metabolic profiling of polar extracts from the direct regenerated shoots was analyzed based on NMR measurements. The results showed that 200 µM MeJA increased production of trigonelline by tenfold. However, the concentrations of several amino acids including alanine were decreased. Based on gas chromatography and mass spectrometry (GC/MS) data, proximadiol concentrations significantly decreased with 10 and 100 µM MeJA. Proximadiol production improved by using 200 µM MeJA, although the data were non-significant. Our findings suggested that, while the addition of MeJA to embryogenic calli improved somatic embryo induction, maturation, and germination, it suppressed organogenic shoot and root formation. MeJA at a particular concentration (200 µM) enhanced the accumulation of trigonelline and osmoprotectant amino acids, while their effect on proximadiol production was statistically non-significant.