Profile Characterization of Volatile Organic Compounds on In Vitro Propagated Plants of Clinopodium Odorum and it’s Comparison with the Wild Plant

The aim of this work was to study the effect of the in vitro culture conditions of plants of Clinopodium odorum on the production of volatile organic compounds (VOCs), and to identify any differences with plants that grow wild. Plantlets were grown with different concentrations and combinations of growth regulators and different media conditions, with or without plant hormones. The VOC profiles of wild and in vitro cultivated plants were determined by HS-SPME/GC-MS, and the results were interpreted by performing statistical tests (principal component analysis (PCA) and conglomerate analysis (CA)). There was a wide variability in the VOC compositions depending on the growing conditions, with (-)-Menthone and Pulegone being the predominant VOCs produced in the most of the media studied. However, Pulegone showed a higher sensitivity to the nutrient composition media, with biosynthesis being favored by low salt concentrations. Moreover, pulegone was accumulated at higher concentrations on Murashige and Skoog (MS) and Gamborg (B5) media at half-strength salt media (MS1⁄2 and B51⁄2), which was dependent on the PGRs and nutrient addition. In conclusion, our present study shows that the micropropagation of C. odorum through in vitro axillary shoot proliferation is a reliable method for the rapid multiplication of this species, which allows the production of VOCs such as those found in spontaneous plants. In this way, we were able to select the most suitable chemotype.