Agastache rugosa (Fisch. & C. A. Mey.) Kuntze - syn. Lophanthus rugosus Fisch. & C. A. Mey. - Lamiaceae
Chinese giant hyssop, Korean mint, purple giant hyssop, Ostasiatischer Riesenysop, Koreaminze
Perennial herb, up to 1m tall, native to Eastern Asia (Korea, Japan, China to Vietnam, Laos); leaves lanceolate to ovate, blueish green, anise scented; flowers tubular, 2-lipped, violet-pink, fragrant, in terminal spikes. The leaves may be used fresh or dry to flavor teas.
„The volatile part of Agastache rugosa, (Labiatae) contains more than 90% of methyl chavicol [= estragole]. The fresh, herbaceous, spicy odor of the ground leaves was therefore caused by methyl chavicol in combination with some minor constituents such as anisaldehyde and p-methoxy cinnamaldehyde.“
[Volatile constituents of Agastache rugosa., Weyerstahl, P., Marschall, H., Manteuffel, E., Huneck, S., Journal of Essential Oil Research, 4(6), 1992, 585-587]
Main components of the essential oil of A.rugosa were estragole (49.4%), limonene (12.5%) and β-caryophyllene (6.4%).
„The essential oil of A. rugosa showed lower fungistatic activity against most of the fungi, as measured by the broth dilution and disk diffusion methods, than estragole. Therefore, the activity of the oil fraction appears to be due mostly to estragole, which comprises half of the oil fraction, while the other components appear to have relatively mild activity… the MIC of ketoconazole alone against B. capitatus was lowered from 25 to 0.78 µg/ml when estragole was added at a concentration of 1.25 mg/ml… Thus, estragole and the essential oil of A. rugosa may be useful in the clinical application of ketoconazole.“
[Antifungal activity of the essential oil of Agastache rugosa Kuntze and its synergism with ketoconazole., Shin, S., Kang, C.A., Letters in applied microbiology, 36(2), 2003, 111-115] http://onlinelibrary.wiley.com/doi/10.1046/j.1472-765X.2003.01271.x/full