Bark, willow

The pharmacological actions of salicylates in humans are well documented and are applicable to willow. In recent clinical studies, willow bark extract had moderate analgesic effects in osteoarthritis and low back pain (93-96). 

There are only a limited number of studies available evaluating the pharmacokinetics of salicin and its major metabolites in humans after oral administration. 

In contrast, oral administration of a willow bark extract showed a low bioavailability of salicin (98). After ingestion of commercial sugar-coated tablets containing willow bark extract corresponding to a total amount of 54.9mg (0.192mmol) salicin, the serum of 12 volunteers showed a peak concentration of only 0.13 pg/mL salicylic acid this is only 5% of the serum 

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W. White, Observations and Experiments on the Broad-Eeaved Willow Bark, Ha2ard, Bath, U.K., 1798. 

The most common NSAID is aspirin, or acctylsalicvlic acid, whose use goes back to the late 1800s. It had been known from before the time of Hippocrates in 400 bc that fevers could be lowered by chewing the bark of willow trees. The active agent in willow bark was found in 1827 to be an aromatic compound called salicin, which could be converted by reaction with water into sal- icy I alcohol and then oxidized to give salicylic acid. Salicylic acid... 

Willow bark (weidenrinde, white willow, purple osier willow, crack willow) S lixalba, purpurea, fragilis Analgesic Adverse reactions are those associated with the salicylates Do not use with aspirin or other NSAIDs. Do not use in patients with peptic ulcers and other medical conditions in which the salicylates are contraindicated. 

No drugs have been a more faithful companion to man throughout his history than salicylates, the forebears of aspirin. About 3,500 years ago the Ebers Papyrus recommended the application of a decoction of leaves of myrtle to the abdomen and back to get rid of rheumatic pains. Hippocrates championed the juices of the poplar tree and willow bark to treat fever and labor pains. These plants and trees are abimdant in compounds derived from salicylic acid, which gets its name from them (in Latin salix is a willow tree). For thousands of years on all continents they have helped to... 

Rue Sweet clover Turmeric Vitamin E Willow bark ... 

Why Is White Willow Bark Known as Nature s Aspirin ... 

Figure 13.4.6 A sequence of reactions yielding salicylic acid from the natural product salcin from white willow bark.

White Willow Bark. Healthy Wave, 1999, http //www.healthywave.com/ingredients/whitewillowbark.html... 

K. Wuthold, I. Germann, G. Roos, O. Kelber, D. Weiser, H. Heinle and K.-A. Kovar, Thin-layer chromatography and multivariate data analysis of willow bark extracts../. Chromatogr. Sci. 42 (2004) 306-309. 

Willow bark has been used throughout recorded history to treat pain, fevers, and inflammation. Its uses have been independently discovered in cultures as diverse as the ancient Greeks, Hottentots, and American... 

Salicin occurs in small amounts in willow, making raw preparations impractical for treatment (Tyler 1994). Between 3 and 20 cups of willow bark tea, depending on salicin content, would be necessary to get an effect. At such high doses, the presence of tannins in the bark would also cause aversive effects. Thus, aspirin is needed to reach therapeutic effects. 

Take aspirin, for example. It has its origins in salicin, the active ingredient in willow bark. When salicin is hydrolysed it produces glucose and salicyl alcohol the latter can be oxidised to salicylic acid. Salicylic acid was also used as a medicine, but it caused irritation and bleeding in the stomach and intestines. However, when salicylic acid is treated with ethanoic anhydride, acetylsalicylic acid (aspirin) is produced. 

Traditionally, lead compounds have been discovered in one of two ways. The hrst is one of trial and error. This is the way many plant and animal products and minerals have been found to be effective in the treatment of some medical disorder. For example, no one knows when the hrst person learned that chewing on the bark of the willow tree [Salix alba) helped relieve pain and reduce fever, but willow bark has been used in many cultures for untold centuries for just that purpose. Today we know that the active ingredient in willow bark is a derivative of salicylic acid (CgH4(OH)COOH), which today is sold commercially as aspirin or one of its analogs. Drug researchers continue to rely heavily on the study of folk medicines—a science known as ethnopharmacology—for the discovery of new plant and animal products that may have medical applications in the modern world. Indeed, scientists have discovered that the medical... 

Tahvanainen, J., Helle, E., Julkunen-Tiitto, R., and Lavola, A. (1985). Phenolic compounds of willow bark as deterrents against feeding by mountain hares. Oecologia 65, 319-323. 

Salicin is an (9-glycoside of a phenol, namely salicyl alcohol. Salicin is a natural antipyretic and analgesic found in willow bark, and is the template from which aspirin (acetylsalicylic acid, see Box 7.13) was developed. Prunasin from cherry laurel is an example of a cyanogenic glycoside, hydrolysis of which leads to release of toxic HCN (see Box 7.7). It is the (9-glucoside of the alcohol mandelonitrile, the trivial name for the cyanohydrin of benzaldehyde. It is the further hydrolysis of mandelonitrile that liberates HCN. 

Nostradamus drank some more willow bark, grimacing at the bitter taste. 

Bah You think I m stupid, to get mixed up in a thing like that If I d thought I could find him, I would have gone after the reward myself I just waited a few days and wrote back that the fugitive must have moved out of my range and I only charge when successful. Case closed. More willow bark. ... 

Nostradamus can always surprise me. Next morning he hobbled into the atelier on his canes, obviously still in pain, and by the time he had settled into his chair, I was there with his willow bark potion. I should properly have slunk quietly away and given him an hour to sheath his fangs, but I was anxious to head off to Palazzo Mchiel. Besides, I wanted to get the ordeal over with. 

Aspirin (acetylsalicylic acid) Willow bark (salicylic acid)... 

Shikim. picein-like (Picea spp., Pinaceae, Gymn. from N conifer forest also from willow bark MI). 

Aspirin is the most widely used medication. Over 10,000 tons of aspirin are used in this country annually, and worldwide the annual consumption is 35,000 tons. The history of acetylsalicylic acid actually goes back thousands of years. Hippocrates (460-377 B.c.) and the ancient Greeks used powdered willow bark and leaves to reduce fever (antipyretic) and as a pain reliever (analgesic). Native American populations also used willow and oil of wintergreen for medication. The chemicals responsible for the medicinal properties in willow and oil of wintergreen are forms of salicylates. Willows (genus Salix) contain salicin and oil of wintergreen contains methyl salicylate. 

Most of the nonsteroidal anti-inflammatory drugs (NSAIDs) are carboxylic acids. Aspirin (8.69) (acetylsalicylic acid, ASA) has been used since the turn of the last century to reduce pain and fever, but the parent compound, salicylic acid, has been known and used since antiquity, owing to its common occurrence as a glycoside in willow bark. Acetylation merely decreases its irritating effect. Among the numerous other salicylates known and used, flufenisal (8.70) has a longer duration of activity and fewer side effects than aspirin. Mefenamic acid (8.71) and flufenamic acid (8.72) are derivatives of anthranilic acid, while ibuprofen (8.73) and naproxen (8.74) are derivatives of phenylacetic and naphthylacetic acids, respectively. 

Glucosidase is a hydrolysing enzyme, and can be used to hydrolyse various glucosides. For example, salicin, found in willow barks, can be hydrolysed to salicyl alcohol by enzyme. 

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