Photo by Stephen Reebs
The bark of Scotch pine, a popular type of Christmas
tree, may contain compounds beneficial to human health.
Scientists have found that Christmas trees have more to offer people than just a dose of holiday cheer. In fact, one tree in particular, Scotch pine (Pinus sylvestris L.), has bark that contains compounds potentially beneficial to human health.
As part of an extensive study of natural extracts in plants, Kalevi Pihlaja and his research team from the University of Turku, in Finland, examined Scotch pine bark and found compounds that inhibit inflammation in mouse cells. In humans, these compounds have the potential to treat conditions such as pain and arthritis. Their research was published in the Journal of Agricultural and Food Chemistry.
“The preliminary study showed that highly purified preparations of pine bark extract have potent anti-inflammatory effects,” says Pihlaja. “In the future, this may mean that people with arthritis may ease their pain by eating food supplements made from Christmas trees.”
Compounds like those found in the Scotch pine bark, known as phenolics, are the subject of growing interest in the scientific and pharmaceutical communities for their potential use in treating maladies. Often, when plants used as traditional folk medicines are studied by scientists, ingredients useful to modern medicine are discovered; such was the case with aspirin, a synthetic compound based upon the chemical structure of salicylic acid, which is found in willow bark and has been used throughout history to treat pain.
Similarly, the parts of many different pine species have been used in traditional medicine, which is one of the reasons Pihlaja and his team suspected the existence of beneficial phenolics in Scotch pine. Europeans have historically used Scotch pine bark in medicines and as supplemental food, and its oils are still used in home remedies for conditions including rheumatism and poor circulation.
Also, recent studies have indicated that Scotch pine bark contains antioxidant compounds – and scientists have found that the bark of another pine, maritime pine (Pinus pinaster), yields the compound pycnogenol, which is currently being investigated for its use in treating and preventing complications from diabetes; it is also marketed as a powerful antioxidant.
After identifying 28 potentially useful compounds in the bark of Scotch pine and armed with evidence of its historical use as a medicine, Pihlaja and his colleagues prepared extracts of the bark in varying concentrations and tested how successful each concentration was against inflammation in mouse cells. The inhibition of the production of nitric oxide and another agent of inflammation called prostaglandin E2, both of which are linked to circulation problems, was used to measure anti-inflammatory activity. The most concentrated extracts inhibited nitric oxide and prostaglandin E2 production to the greatest extent. Nitric oxide production was inhibited by 63 percent and prostaglandin E2 production was inhibited by 77 percent, when measured against untreated cells.
One of the compounds isolated from the Scotch pine bark extracts is ferulic acid, which has known antioxidant and other beneficial properties, but it is unclear whether the anti-inflammatory activity of the extracts is due to one compound (known or yet-to-be-discovered) or the dynamics of several found in the bark. What is clear is that Scotch pine bark will continue to be a useful medicine for people.