Shedding light on the volatile organic compounds of Rutagraveolens through HS-SPME: study of the effect of light spectral quality and UV-B radiation

Ríos-Ríos A.M.; Ix-Balam M.A.; David G.F.; Siqueira da Silva J.V.; Marçal Fernandes J.V.; de Queiroz V.T.; Batista D.S.; Ferreira da Cruz A.C.; de Jesus Pereira L.; Otoni W.C.; Fernandes S.A. · Plant Cell, Tissue and Organ Culture (2026) · DOI: 10.1007/s11240-025-03311-z

Resumen

The biosynthesis of volatile organic compounds (VOCs) can be stimulated by elicitors during the micropropagation of medicinal plants such as Ruta graveolens. However, the inherently low biomass of in vitro-grown plants limits comprehensive characterization of their volatile profiles. Headspace solid-phase microextraction (HS-SPME) offers a practical alternative to overcome this constraint. This study aimed to (i) identify VOCs storage sites through histochemical analysis, (ii) establish optimal HS-SPME conditions for VOCs extraction, and (iii) evaluate the effects of blue, red, blue/red, far-red, and white LEDs, as well as different UV-B exposure times (0, 0.5, 1, 2, and 4 h day−1), on VOCs production in in vitro R. graveolens plants. Essential oils were localized in secretory cavities, trichomes, and epidermal tissues. The DVB/CAR/PDMS (50/30 µm) fiber exhibited the highest selectivity for extracting ethers, esters, ketones, and monoterpenes when using 200 mg of fresh shoots and a 30-min extraction period. Ketones, particularly nonan-2-one (~53%), along with esters and sesquiterpenes, were the predominant constituents. Red LEDs enhanced the production of limonene, 3,4-diethenyl-3-methylcyclohexene, and geijerene, while reducing levels of the primary alcohol nonan-1-ol. Blue LEDs increased the relative abundance of octyl acetate. Exposure to UV-B for 1 h day−1 reduced total monoterpene content but increased nonan-1-ol accumulation. The optimized HS-SPME protocol provides an effective approach for investigating stress-induced alterations in volatile biosynthesis in micropropagated medicinal plants. Notably, this work presents the first evidence of the influence of light spectral quality and UV-B exposure on the volatile composition of in vitro-grown R. graveolens plants. © The Author(s), under exclusive licence to Springer Nature B.V. 2025.

Instituciones: Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas