Objective: To determine the content of rosmarinic acid in seeds and its processed products of Perilla frutescens var. typica (PFT), Perilla frutescens var. acuta (PFA) and Perilla frutescens var. acuta form. discolor (PFAD).
Methods: The content of rosmarinic acid was determined by RP-HPLC with Welch C18 (250 mm x 4.6 mm, 5 microm) column, using methanol-phosphonic acid solution (39:61) as mobile phase at flow rate of 1.0 mL/min. UV detection wavelength was set at 330 nm and column temperature was set at 28 degrees C.
Results: The content of rosmarinic acid in roasted seeds of PFT is higher than in its seeds, but that of PFA and PFAD are lower; The content of rosmarinic acid in seeds of PFT, PFA and PFAD decline after the seeds are honey-pocessed and made into frost-like powder, and that of honey-processed one decline by a larger margin.
Conclusion: The content of rosmarinic acid in seeds of PFT, PFA and PFAD are prone to decline by heat-processing.