Lamium purpureum (from Latin purpureum – purple), known as red dead-nettle,[2]purple dead-nettle, or purple archangel,[3] is an annual herbaceous flowering plant. It is native to Eurasia but can also be found in North America.
Description
Lamium purpureum grows with square stems to 5–20 centimetres (2–8 in),[4] rarely 40 cm, in height.[5] The leaves have fine hairs, are green at the bottom and shade to purplish at the top; they are 2–4 centimetres (3⁄4–1+1⁄2 in) long and broad, with a 1–2 cm petiole (leaf stalk), and wavy to serrated margins.
The zygomorphic flowers are bright red-purple, with a top hood-like petal, two lower lip petal lobes and minute fang-like lobes between. The corolla shows a line of hairs near the base of the tube.[4] They may be produced throughout the year, including mild weather in winter.
Phytochemistry
The essential oil is characterized by its high contents of germacrene D.[6] The seed oil contains 16% of an acid characterized as (−)-octadeca-5,6-trans-16-trienoic acid (trivial name `lamenallenic acid'). Other unsaturated esters identified by their cleavage products are oleate, linoleate and linolenate.[7]
The plant contains phenylethanoid glycosides named lamiusides A, B, C, D and E.[8] It possesses a flavonol 3-O-glucoside-6″-O-malonyltransferase.[9]
Similar species
It is often found alongside henbit dead-nettle (Lamium amplexicaule), for which it is easily mistaken, because the two species bear not only similar leaves, but also similar bright purple flowers. They can, however, be distinguished from one another by the form of the leaves on their respective flowering stems: those of red dead-nettle are petiolate, while those of henbit dead-nettle are sessile.[4]
Though superficially similar to species of Urtica (true nettles) in appearance, L. purpureum is not related to them, the genus Lamium belonging to the mint family, not the nettle family, the "dead" in the name "dead-nettle" referring to the inability of Lamium species to sting.
Lamium purpureum is native to Europe and Asia[citation needed] but it can also be found in North America.
It is a common weed in the western and eastern United States,[12] Canada, Ireland, and the British Isles.[13] It frequently occurs in meadows, forest edges, roadsides and gardens.[4]
Ecology
The year-round flowers allow bees to gather their nectar for food when few other nectar sources are available. It is also a prominent source of pollen for bees in March/April (in UK), when bees need the pollen as protein to build up their nest.[citation needed] The pollen is crimson red in colour and thus very noticeable on the heads of the bees that visit its flowers.[14][15]
Uses
Young plants have edible tops and leaves, used in salads or in stir-fry as a spring vegetable. If finely chopped it can also be used in sauces.[16] The flowers can be crystallized using sugar and egg white.[5]
The herb has a venerable pedigree in the folk medicine of England, featuring as it does as one of three medicinal/symbolic plants called for in the Anglo-Saxon herb charm Wið færstice[wiðˈfæːrˌsti.t͡ʃe] (meaning 'against a sudden/violent stabbing pain'). The charm in question (dating, according to scholarly consensus, probably from the late ninth century) calls for the three herbs involved (the other two being feverfew and plantain) to be heated in butter to prepare an ointment, which is then rubbed on the site of the pain with the blade of a knife, while the lengthy charm is recited by the folk practitioner, who thereby aligns herself (or himself) with the patient – in contradistinction to the evil supernatural beings believed to have caused the pain with their magical arrows.[17]
To this day, herbalists use red dead-nettle in many herbal remedies. One of these is a salve prepared from the plant which can be used topically to soothe irritated, itchy, or sore skin.[18] Studies show a strong antioxidant effect.[19]
^Flamini, G.; Cioni, P. L.; Morelli, I. (2005). "Composition of the essential oils and in vivo emission of volatiles of four Lamium species from Italy: L. Purpureum, L. Hybridum, L. Bifidum and L. Amplexicaule". Food Chemistry. 91: 63–68. doi:10.1016/j.foodchem.2004.05.047.
^Suzuki, H. (2004). "CDNA cloning and functional characterization of flavonol 3-O-glucoside-6"-O-malonyltransferases from flowers of Verbena hybrida and Lamium purpureum". Journal of Molecular Catalysis B: Enzymatic. 28 (2–3): 87–93. doi:10.1016/j.molcatb.2004.01.005.
^Whitson, Tom (2000). Weeds of the West. Newark, California: Western Society of Weed Science in cooperation with the Western United States Land Grant Universities Cooperative Extension Services. ISBN9780788149269.
^Clapham, A.R., Tutin, T.G. and Warburg, E.F. 1968. Excursion Flora of the British Isles. Cambridge University Press. ISBN0-521-04656-4
^Dorothy Hodges (1952). The pollen loads of the honeybee. Bee Research Association Ltd., London.
^Bubueanu, Corina; Gheorghe, Campeanu; Pirvu, Lucia; Bubueanu, George (5 September 2013). "ANTIOXIDANT ACTIVITY OF BUTANOLIC EXTRACTS OF ROMANIAN NATIVE SPECIES -Lamium album AND Lamium purpureum". Romanian Biotechnological Letters. 18 (6): 8861.