Monday, December 6, 2021

Willow: Herb of the Week

 

Salix daphnoides, European Violet Willow

---Standard disclaimers: I am not a doctor. Read this information for entertainment value---

"Everybody knows" that willow bark is a good source of aspirin, right?

Well, it is never quite that simple. Some of the ancient Greeks referenced the use of willow bark to break fevers and then the knowledge seemed to disappear until Dr. Quinn Medicine Woman rediscovered in on Prime Time TV just in time to inform scientists in Europe.

There are several complications. One complication is that various species of willow have wildly varying amounts of salicin (and derivatives). A second complication is that the percentage of salicin varies modestly depending on the time-of-year. The third complication is that even the willow species with low concentrations of salicin contain "Flavonoids and polyphenols (that) contribute to the potent willow bark analgesic and anti-inflammatory effect."

Salicins as anticoagulants

You can make a credible case for the reduced mortality rate of ischemic events (heart attacks, strokes) in the US being attributable to the widespread use of anticoagulants prophylactically, That is, widespread use of low-dose (aka Baby) aspirin for at-risk patients.

The actual mechanics of an ischemic event is an obstruction in a vein or artery developing a clot and then the clot breaking loose and lodging in an artery where it branches, thereby causing the tissue downstream of the lodged clot to be deprived of oxygen and potentially dying.

Inflammation of the vessel walls are implicated in the sudden growth of clots. Obstructed blood vessels are a very minor issue and a person can not even know they have them. It is only when a clot starts to form and its growth accelerates.

So aspirin (a complex of acetic acid and salicylic acid) is effective from the anticlotting perspective because it binds to blood proteins .AND. reduces inflammation. Even though its pain and inflammation reducing effect has a half-life of four hours the anticlotting effect throws a much longer shadow and is still effective after 48 hours.

Salicin as a fever, inflammation and pain reducer

It is awesome if it is all you have. Contraindicated for young people with the flu due to Reyes syndrome. Contraindicated for people with underlying, bleeding disorders. Contraindicated for people with gastric ulcers or acid reflux issues.

Salicin as a percentage of bark, by species

Source

Salicin (and derivatives) content of 32 willow clones grown and tested in Latvia ranged from 0.05% (500 PPM) for Salix viminalis clone 109 to 12.06% (120,000 PPM) for Salix acutifolia. Stated another way, the highest concentration is 240 times higher than the lowest concentration.

This study is by no means exhaustive. There are hundreds of species of willow and they hybridize freely.

The four species that tipped the scales at over 5% salicin when sampled in the spring (by far the easiest time to "slip" the bark off the wood) were:

  • Salix acutifolia at 10.8%
  • Salix daphnoides at 9.5%
  • Salix purpurea at 6.4%
  • (Salix integra × Salix kochiana) at 5.9% 
Of these four, Salix purpurea is the most readily available in commerce. It is an easy grower and Dr. Larry Smart, a willow researcher at SUNY calls Salix purpurea the bush-willow equivalent of a lab-rat.

Incidentally, Dr. Smart has a vast collection of willow clones and is looking for some seed-money to prime the pump for institutional funding to characterize the nutritional and pharmaceutically active chemicals in a cross-section of the collection.

Additionally, the research looked at seven different Salix purpurea clones and hybrids and they were uniformly high in salicin.

Salix purpurea is very commonly grown for withes for fine wicker-work. Cuttings are available from Double-A Willow and Vermont Willow. Vermont Willow also offers five varieties of Salix daphnoides.

Non-salicin effects
Many believe that willow is the natural source of aspirin. However, willow species contain only a low quantity of the prodrug salicin which is metabolized during absorption into various salicylate derivatives. If calculated as salicylic acid, the daily salicin dose is insufficient to produce analgesia. Salicylic acid concentrations following an analgesic dose of aspirin are an order of magnitude higher. Flavonoids and polyphenols contribute to the potent willow bark analgesic and anti-inflammatory effect. The multi-component active principle of willow bark provides a broader mechanism of action than aspirin and is devoid of serious adverse events. In contrast to synthetic aspirin, willow bark does not damage the gastrointestinal mucosa. An extract dose with 240 mg salicin had no major impact on blood clotting. In patients with known aspirin allergy willow bark products are contraindicated.    Source


Bold and underlined is mine.

The underlined sentence is suspect until it is replicated. 

Bonus link

The present study is a continuation of the research that was previously described by Sulima et al. (2017). The experimental materials comprised 29 S. purpurea genotypes that were selected from 91 genotypes acquired in 13 natural locations in north-eastern Poland. The genotypes used in the experiment were propagated in vitro, and were used to establish a field experiment in the Agricultural Experiment Station in Bałdy (N53°35′45.442″/E20°36′10.616″) operated by the University of Warmia and Mazury in Olsztyn.
Based on the results of the present study, genotypes OL 1/1 and ELK 2/2 were registered as cultivars ASPI and ASPIRA in the Research Center for Cultivar Testing. These cultivars are characterized by a very high (OL 1/1) and high (ELK 2/2) content of SG in the bark as well as supreme yield-related traits. Both genotypes were completely free of Melampsora spp. infection, which could suggest that they are highly resistant to leaf rust. In the group of the remaining S. purpurea genotypes, particular attention should be paid to genotypes ELK 1/1 (with only somewhat lower productivity) and ELK 2/9 (with somewhat lower SG content). The present findings validate the research hypothesis postulating that S. purpurea genotypes from natural locations are highly suitable for agricultural production of high-quality herbal raw material under controlled conditions.


Second bonus link

A very simple method of detection of the free salicylic acid could be based on the different coordinating capacity of the salicylic derivatives with the octahedral Fe+3 cation. Thus, the yellow FeCl3 aqueous solution turns pale pink in contact with an aqueous solution of acetylsalicylic acid, but turns dark blue in the presence of a very light quantity of free salicylic acid.

8 comments:

  1. Good info. It appears that you put some effort into this. I will definitely study this. It may turn out to be very important for us. Thanks much---ken

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  2. Very informative piece Joe, I am part of a project of rewinding small areas on a small holding where the land is used primarily for the livery of horses. Not that I know much about these beasties but one of the plants we are planting more of is Goat Willow which the horses have a particular likening for the new growth. The primary reasons for the Willow is that it is a native species, excellent for many invertebrates and fast growing. I Kew about the aspirin connection but your post gives a much deeper insight..
    Regards John

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  3. Yes, willow is the earliest plant to bloom in spring and provides flowers for Easter even in Russia. There are at least four commercially available species in Michigan through traditional nurseries. I also raise stock from Vermont Willow Nursery in various colors for winter interest and basketry. The number of homestead items that can be woven is basically limitless, from garden structures to furniture to baskets to lampshades etc etc. I can’t think an easier plant to grow from cuttings so definitely an easy trade as well. Good post Joe! —

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    Replies
    1. Thanks for commenting.

      Do you want to share contact information so readers can purchase from you?

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  4. Alaska also has probably the latest blooming variety with the road side near us looking like snow covered shrubs long after the first hard freeze. Also patients with serious risk of stroke or heart attack are prescribed much more serious anti clotting drugs such as Coumadin (main ingredient in rat poison). Of course when they move to a location forty miles from the nearest 24 hour medical facility it’s back to aspirin or a mid strength anti coagulant as the danger from bleeding out from an accident or major cut is more likely to be fatal than a stroke. It’s a matter of percentages. Since I have been dealing with afib for 25 years I’ve heard all the pros and cons.

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  5. Purely for informational purposes....since you are not a Dr. and dont even play one on TV, how is the Willow bark " administered" ?? Any info from Dr. Quinn or others? Do you cut off some branches and make a tea??? Do you actually strip the bark off???

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