Comparative Analysis of Metabolite Profiles of Perilla frutescens Britton var. acuta Kudo (Lamiaceae) Leaves Collected from Different Regions in South Korea

Perilla frutescens Britton var. acuta Kudo leaves are widely consumed in East Asia due to their culinary and medicinal properties, which are largely attributed to their high levels of bioactive metabolites such as rosmarinic acid. In this study, we investigated the variation in rosmarinic acid content and overall metabolite profile of P. frutescens leaves collected from six different provinces in Republic of Korea. Quantitative analysis of the rosmarinic acid content was performed using HPLC, revealing significant regional differences, with the highest concentration observed in the leaves collected in Gyeongsangbuk-do and the lowest concentration in those from Jeollanam-do. HRESIMS and ¹H-NMR spectrometry were used to determine the chemical structure of the isolated rosmarinic acid. LC-Q-TOF/MS analysis identified ten major metabolites, including phenolic acids, flavonoids, and triterpenoids. Multivariate statistics (OPLS-DA) revealed distinct clustering of populations, indicating a strong relationship between metabolites and environmental parameters. The distribution of the metabolite fingerprints and rosmarinic acid contents in P. frutescens leaves were also found to differ according to the cultivation region, suggesting that secondary metabolite expression is influenced by environmental and geographic factors. This work shows that metabolome profiles can be used in quality control and the development of high-quality products derived from P. frutescens.