The effects of methyl jasmonate on volatile compounds and activity of aroma-related enzymes in tobacco

Fecha de publicación: 01/09/2024
Fuente: Broccoli Byproducts Extraction
Abstract
Flue-cured tobacco, a member of the Solanaceae family, is widely utilized as a model organism in both fundamental and applied scientific research. This study set out to evaluate the influence of the exogenous agent methyl jasmonate (MeJA) on the aroma profile of tobacco by applying various MeJA concentrations (0 μmol/L, 30 μmol/L, 60 μmol/L, 90 μmol/L and 120 μmol/L) to the leaves 48 h prior to harvest. Assessments included an analysis of volatile compounds, sensory evaluations, and enzymatic activity fluctuations, followed by cluster and correlational analyses. The results showed that under 90 μmol/L MeJA treatment, the relative content of benzyl alcohol, which was phenylpropane aroma substance, increased by 79.48%, compared with the control (0 μmol/L MeJA). Sensory evaluations also ranked MeJA-treated tobacco as superior, with the most prominent enhancement in smoking quality occurring at the 90 μmol/L concentration. Under MeJA treatments, the activities of aroma-related enzymes polyphenol oxidase, peroxidase, phenylalanine ammonia-lyase, and 4-coumarate:CoA ligase (4CL) were enhanced, with 4CL activity showing the most significant change (3.56 times higher than the control). Therefore, the optimum concentration for improving the aroma quality of tobacco is 90 μmol/L MeJA. Correlative analyses further reveal a substantial and intimate link between the activities of key enzyme activities, sensory quality, and volatile compounds. This indicates that MeJA promotes the accumulation of phenylpropane aroma volatiles by regulating the activity of key enzymes in the phenylpropane pathway, ultimately enhancing the sensory quality of tobacco.