Germacrone is a sesquiterpene and key bioactive constituent of many essential oils. [1] It was first detected in essential oil of Geranium macrorrhizum (bigroot geranium) in 1927. [1] More recently and famously, it has played a major role in essential oils extracted from Curcuma L., which is a genus in the ginger (Zingiberaceae) family spanning over 100 species including turmeric (C.longa) and other rhizomatous herbs. [2] Plants with essential oils high in germacrone are found in many countries around the world. [1]
Germacrone is associated with a wide range of potential beneficial properties, including anti-inflammatory, antitumor, antibacterial, cough-suppressant, vasodilator, and hepatoprotective activities, among others. [1] For instance, germacrone is largely credited for the anti-inflammatory properties of C. xanthorrhiza, or Java ginger, a popular Indonesian medicine. The same goes for the antifungal effects of Myrica gale (sweetgale) essential oil and the broad-spectrum antibacterial activity of Asarum caulescene (wild ginger) essential oil. An extracted oil from fruits of Eugenia uniflora (Surinam cherry) exhibited 27.5% content of germacrone that is believed to largely fuel cytotoxic effects against human prostate, liver, and breast tumor cells. [1]
In mice, germacrone has been shown to prolong or provoke sleep alongside hexobarbital, possibly due to depressant effects on the central nervous system. [1]
Germacrone was found to protect mice against lethal infection from influenza A (H1N1 and H3N2) and B by inhibiting the “attachment/entry step and the early stages of the viral replication cycle” in a dose-dependent fashion. [3] In addition, when working in combination with oseltamivir, it “exhibited an additive effect on the inhibition of influenza virus infection, both in vitro and in vivo.” [3]
On a somewhat different note, germacrone has also displayed the ability to improve the skin penetration of minoxidil, a hair growth promoter, and also acted as an “anti-androgen, thereby introducing a more effective topical treatment strategy for androgenic alopecia.” [4] Androgenic alopecia is another way of saying male or female pattern baldness. Co-application was more effective than either treatment alone due to the ability of germacrone to enhance the absorption of minoxidil. [4]
The efficacy of germacrone’s abilities are exceeded only by their diversity, and we’re curious to see future studies that explore potential synergistic interactions with cannabinoids.
Image: Danny S., CC By-SA 3.0
References:
- Barrero AF, et al. Germacrone: Occurrence, synthesis, chemical transformations and biological properties. Natural Product Communications. 2008;3(4):567 – 576. Journal Impact Factor = 0.468; Times Cited = 3
- Li S, et al. Chemical composition and product quality control of turmeric (Curcuma longa). Pharmaceutical Crops. 2011;2:28-54. https://scholarworks.sfasu.edu/agriculture_facultypubs/1. Journal Impact Factor = n/a; Times Cited = 188
- Liao Q, et al. Germacrone inhibits early stages of influenza virus infection. Antiviral Research. 2013;100(3): 578-588. Journal Impact Factor = 4.101; Times Cited = 22
- Srivilai J, et al. Germacrone and sesquiterpene-enriched extracts from Curcuma aeruginosa increase skin penetration of minoxidil, a hair growth promoter. Drug Delivery and Translational Research. 2017. Journal Impact Factor =3.041; Times Cited = 7