Alternative Mistletoe Uses Revealed by NMR

Are you dreaming of a white Christmas? Or maybe your hopes are pinned more on being able to steal a Christmas kiss under the mistletoe with that special someone?

Mistletoe has adorned homes for centuries. The ancient Druids believed that it would ward off evil spirits, whereas in Norse mythology it was a sign of love and friendship. The goddess of love, called Frigg, declared that mistletoe should be a plant of love after her beloved son Baldr was killed with a mistletoe spear.

Fast forward to the eighteenth century; British servants built on the romantic Norse imagery, using mistletoe as an excuse to steal a cheeky yuletide kiss. It seems that somehow, who knows why, that this was the tradition that stuck and the wide association of mistletoe with Christmas remains. Mistletoe is represented in Christmas lights and tree decorations, appears on cards and wrapping paper, is sung about in Christmas hits and is, of course, hung above numerous doorways.

The European white-berry mistletoe (Viscum album Loranthaceae), however, has so much more to offer than pretty decoration and the promise of a Christmas kiss. It is among the oldest known medicinal plants and its extracts have been extensively used in the treatment of hypertension, diabetes, epilepsy and cancer. Promising anticancer activity has been reported for a range of different cancer cell lines, including prostate cancer, mammary gland and cervical adenocarcinomas and lymphoblastic leukaemia.

Despite the curative potential of mistletoe, little is known about the composition of mistletoe extract. The elusive nature of this natural remedy, however, is starting to be unravelled with the help of nuclear magnetic resonance spectroscopy (NMR).

Analysis of the purified components of European white-berry mistletoe extract using a Bruker 600 MHz spectrometer equipped with a cryogenic probe has revealed a new type of natural product.  The mistletoe extract was shown to include compounds comprising phenolic acids merged with the methyl ester of γ-hydroxybutyric acid (GHB) that are not closely related to any known natural product. This NMR evaluation of mistletoe extract has thus defined a novel group of natural products.

The two novel compounds discovered were 3-(3′-carbomethoxypropyl) gallic acid and 3-(3′-carbomethoxypropyl)-7→3″-protocatechoyl galloate. Condensation of the 3-hydroxyl of gallic acid with the 4-hydroxyl of GHB significantly reduced the radical scavenging properties of the former compound.

Knowing the broad medicinal properties of mistletoe, it is possible that the newly identified novel aminoalkaloid compounds present in European white-berry mistletoe extract may have potential as future drug candidates and should be further investigated.

Now there is an interesting conversation piece for when you have your next encounter under the mistletoe!

Reference

Amer B, et al. Novel GHB-derived natural products from European mistletoe (Viscum album). Pharmaceutical Biology 2013;51(8):981‑986.