How do dock leaves work?

I’ve already written extensively about the right way to use dock and how powerfully it works. The trick being to use the gel found inside the young, furled leaf sheath and not to just rub old leaves together. But here I thought I’d try to explain the chemistry behind why dock leaves work from a biochemical reason.

Why dock leaves work

First of all, this has not been an easy task. It costs money to do laboratory analysis and research, plus a lot of time and effort to submit papers for publication in a peer-reviewed journal. As no one is going to easily patent the humble dock (although some once tried) to make money from it, providing the evidence is purely a curiosity and, as a result, is scarce.

The main clue is in a family of phytochemicals called anthraquinones. In aloe vera gel – a well-known, pain-relieving gel – two of the most important anthraquinones are aloin and emodin. They are both pain-killing (analgesic) as well as laxative compounds. Dock root (Rumex obtusifolius) also contains anthraquinones of which two are emodin and aloe-emodin. In addition to being inherently analgesic, these anthraquinones can also generate salicylic acid (Nature’s aspirin) via enzymes, when under attack. (Coincidentally, emodin and aloe-emodin are also effective against the herpes simplex virus (HSV1 and HSV2). Dock is also very high in chrysophanol and physcion which are both anti-inflammatory. This would explain why dock leaf gel worked so well on my hot oil burn. It also contains rhein (shown to exhibit antimicrobial and antibiotic properties), another anthraquinone.

References

Fairbairn, J.W. & El-Muhtadi, F.J. (1972). Chemotaxonomy of anthraquinones in Rumex. Phytochemistry, 11(1), 263-268. doi: 10.1016/S0031-9422(00)90001-3

Rao, K.N.V., Sunitha, C., Banji, D., Sandhya, S., & Mahesh, V. (2011). A study on the nutraceuticals from the genus Rumex. Hygeia.J.D.Med. 3(1), 76-88.

Mulisa, E., Asres, K., & Engidawork, E. (2015). Evaluation of wound healing and anti-inflammatory activity of the rhizomes of Rumex abyssinicus J. (Polygonaceae) in mice. BMC Complement Altern Med. 15, 341. doi: 10.1186/s12906-015-0878-y

Vasas, A., Orbán-Gyapai, O., & Hohmann, J. (2015). The Genus Rumex: Review of traditional
uses, phytochemistry and pharmacology. J Ethnopharmacol. 175, 198-228.
doi: 10.1016/j.jep.2015.09.001

Zhang, N., Zhang, X., Liu, X., et al. (2014). Chrysophanol inhibits NALP3 inflammasome activation and ameliorates cerebral ischemia/reperfusion in mice. Mediators Inflamm. 370530. PMID: 24876671. doi: 10.1155/2014/370530.

Featured post image by Sten Porse – Own photo, taken in Jutland., CC BY-SA 3.0