Mentha spicata L., as a rich source of phenolic acids, is known for its therapeutic importance. Elicitors play a crucial role in biosynthetic pathways to improve plant secondary metabolites production. The purpose of this study was to investigate the effect of methyl jasmonate (MeJA) as a potent elicitor, on phenolic acids production and the relative changes in expression of their biosynthesis-related key genes (PAL, TAT, C4H, HPPR, and 4CL) in M. spicata hairy root cultures, to elucidate the interrelation between phenolic acids accumulation and the regulation mechanism of gene expression. The results showed that the relative expression levels of phenylpropanoid pathway genes, i.e., PAL, C4H, 4CL, and HPPR in the tyrosine-derived pathway increased 4.04-fold, 3.62-fold, 1.75-fold, and 1.45-fold in comparison to untreated controls, respectively. High-performance liquid chromatography analysis indicated that MeJA dramatically increased rosmarinic acid content (55.44 µg g⁻¹ dry wt, about 11.84-fold) after 6 h exposure to elicitor. Moreover, caffeic acid, chlorogenic acid, and cinnamic acid contents were also enhanced significantly (p < 0.05) in response to MeJA treatment. On the other hand, the application of MeJA had a negative effect on both TAT expression level and lithospermic acid B accumulation. Our results implied that MeJA has a significant impact on RA, CA, CGA, and CIA accumulation, which might be the consequence of gene activation from the phenylpropanoid pathway (PAL, C4H, and 4CL) and HPPR, a key regulatory enzyme of the tyrosine-derived pathway in the elicitor-treated hairy root cultures of M. spicata.

薄荷油作为酚酸的丰富来源，因其治疗重要性而闻名。促进剂在改善植物次生代谢产物的生物合成途径中起着至关重要的作用。这项研究的目的是研究茉莉酸甲酯（MeJA）作为有效激发子对酚酸产生及其与生物合成相关的关键基因（PAL，TAT，C4H，HPPR和4CL）表达的相对变化的影响。在sp。毛状根培养，以阐明酚酸积累与基因表达调控机制之间的相互关系。结果表明，与未经处理的相比，酪氨酸衍生途径中苯丙烷类途径基因（PAL，C4H，4CL和HPPR）的相对表达水平分别提高了4.04倍，3.62倍，1.75倍和1.45倍控件。高效液相色谱分析表明，在暴露于引发剂6 h后，MeJA显着提高了迷迭香酸含量（55.44 µg g ^-1干重，约11.84倍）。此外，咖啡酸，绿原酸和肉桂酸含量也显着提高（p <0.05）对MeJA治疗有反应。另一方面，MeJA的应用对TAT表达水平和紫草酸B积累均具有负面影响。我们的结果表明，MeJA对RA，CA，CGA和CIA的积累具有重要影响，这可能是苯丙氨酸途径（PAL，C4H和4CL）和酪氨酸关键调节酶HPPR激活基因的结果。衍生途径中的激发剂处理过的发根培养物M.兰香。