Two new taraxerane-type triterpenes from Ledum palustre L.
Zhang K, Wang J, Chen L, Li J, Shi Z, Zhang S, Zhao M.
Nat Prod Res. 2019 Mar 31:1-6. doi: 10.1080/14786419.2019.1586689.

Simultaneous Determination of Aesculin, Aesculetin, Fraxetin, Fraxin and Polydatin in Beagle Dog Plasma by UPLC-ESI-MS/MS and Its Application in a Pharmacokinetic Study after Oral Administration Extracts of Ledum palustre L.
Wang Z, Zhu W, Liu H, Wu G, Song M, Yang B, Yang D, Wang Q, Kuang H.
Molecules. 2018 Sep 7;23(9). pii: E2285. doi: 10.3390/molecules23092285.

Investigation of the enhancement effect of the natural transdermal permeation enhancers from Ledum palustre L. var. angustum N. Busch: Mechanistic insight based on interaction among drug, enhancers and skin.
Nan L, Liu C, Li Q, Wan X, Guo J, Quan P, Fang L.
Eur J Pharm Sci. 2018 Nov 1;124:105-113. doi: 10.1016/j.ejps.2018.08.025.

Preparation and quality evaluation of microcapsules of volatile oil from Ledum palustre.
Lv M.
Zhong Yao Cai. 2014 Apr;37(4):675-8

Composition of the essential oil of the Rhododendron tomentosum Harmaja from Estonia.
Raal A, Orav A, Gretchushnikova T.
Nat Prod Res. 2014;28(14):1091-8. doi: 10.1080/14786419.2014.907287.

Rhododendron tomentosum (Ledum palustre). A review of traditional use based on current research.
Dampc A, Luczkiewicz M.
Fitoterapia. 2013 Mar;85:130-43. doi: 10.1016/j.fitote.2013.01.013.

Preparation and authentication of beta-cyclodextrin complex of volatile oil from Ledum palustre.
Xue F, Yin SY.
Zhong Yao Cai. 2009 Dec;32(12):1898-902.

Determination of ursolic acid in Ledum palustre L. by RP-HPLC].
Ma X, Mao Z, Zheng C, Sun Y, Zhou B.
Se Pu. 2006 Mar;24(2):208.

The Ledum palustre (rhododendron tomentosum Harmaja) or Wild rosemary, is an evergreen shrub, very perfumed and belongs to the family ericaceae.

Widespread in northern Europe, Asia and North America.

The essential oil of Ledum palustre has an abundant content of polyphenols with potential analgesics, anti-inflammatory, antimicrobial, antiviral, antifungal activities demonstrated in vivo and in vitro studies. In addition, recent scientific research has reported the promising antidiabetic, antioxidant and anticancer properties of this plant (1).

The topical combination of mountain arnica and Ledum palustre may be effective in reducing postoperative ecchymosis and oedema after oculofacial surgery (2).

The anti-inflammatory activity of two extracts of the aerial parts of the Ledum palustre has been established with a significant improvement of the edema (50-73%) for the essential oil obtained by hydrodistillation and (52-80%) for oil obtained by supercritical fluid extraction. These results were similar to those obtained with piroxicam (70%) and ketoprofen (55%) (3).

The essential oil of Ledum palustre, which gives a coniferous aroma to the herbal teas is a precious source of ascorbic acid that acts as a tonic, improving digestion and relaxing activity. However, this drink should not be drunk more than once a day due to the toxicity of ledol and grajanotoxin (4).

In the branches of the ledum is present the ursolic acid, a known triterpene (5) used by athletes, in cosmetics and for the cure of obesity.

Ledum palustre studies

References_________________________________________

(1) Dampc A, Luczkiweicz M. Rhododendron tomentosum (Ledum palustre). A review of traditional use based on current research. Fitoterapia. 2013;85:130–143. doi: 10.1016/j.fitote.2013.01.013.

(2) Assessing the Effectiveness of Arnica montana and Rhododendron tomentosum (Ledum palustre) in the Reduction of  Ecchymosis and Edema After Oculofacial Surgery: Preliminary Results.  Kang JY, Tran KD, Seiff SR, Mack WP, Lee WW.  Ophthal Plast Reconstr Surg. 2017 Jan/Feb;33(1):47-52. doi: 10.1097/IOP.0000000000000645.

(3) Supercritical CO₂ extract and essential oil of aerial part of Ledum palustre L.--Chemical composition and anti-inflammatory activity.  Baananou S, Bagdonaite E, Marongiu B, Piras A, Porcedda S, Falconieri D, Boughattas NA.  Nat Prod Res. 2015;29(11):999-1005. doi: 10.1080/14786419.2014.965167.

(4) Labrador tea--the aromatic beverage and spice: a review of origin, processing and safety.  Dampc A, Luczkiewicz M.  J Sci Food Agric. 2015 Jun;95(8):1577-83. doi: 10.1002/jsfa.6889.

(5) Antioxidant, anti-inflammatory and anticancer activities of methanolic extracts from Ledum groenlandicum Retzius.  Dufour D, Pichette A, Mshvildadze V, Bradette-Hébert ME, Lavoie S, Longtin A, Laprise C, Legault J.  J Ethnopharmacol. 2007 Apr 20;111(1):22-8. Epub 2006 Oct 26.