Scientists from the University of Warmia and Mazury are working on growing a new variety of willow with a high content of salicylates in the bark. It will be used to produce a herbal raw material that can replace synthetic aspirin.
Salicylic glycosides contained in willow bark have healing properties similar to acetylsalicylic acid, i.e. synthetic aspirin. They have analgesic, antipyretic, anti-inflammatory and antiseptic properties. Preparations made of powdered bark contain natural buffering compounds and – unlike aspirin – they do not cause negative side effects for the digestive system.
Scientists from the Department of Plant Breeding and Seed Science at the University of Warmia and Mazury want to use the growing interest of the pharmaceutical industry in herbal raw material. Dr. Paweł Sulima, who conducts research on a new variety of willow, assured that they are the only ones in Poland to conduct research on obtaining their own variety of purple willow with the highest salicylate content in the bark. The new variety will be intended for field crops. Farmers who choose such plantations could contract and sell their crops directly to pharmaceutical companies.
Controlled crops would be a constant source of high-quality herbal raw material. Currently, willow bark for the production of plant preparations is obtained from natural sites.
The material collected in this way is not homogeneous. It comes from many species of willow, plants with different genotypes, sometimes it contains impurities. Therefore, it requires laboratory analyzes, which significantly increases the cost of obtaining the raw material – assessed the scientist from Olsztyn.
Purple willow (Salix purpurea), common in Poland, which is considered a species with a high concentration of salicylates, was selected for the experiments. The individual forms of purple willow, however, show significant differentiation in terms of the percentage of these compounds. Therefore, researchers from Olsztyn are trying to select the appropriate genotypes and create a new variety with the maximum content of salicylic glycosides.
We have collected nearly 100 different purple willow genotypes from natural sites, which we evaluate in terms of their suitability for the pharmaceutical industry. We also select the potentially best parental forms for crossbreeding, thanks to which we can obtain offspring with the desired parameters – explained Sulima.
The research uses molecular techniques based on DNA analysis, which enables, among others, identification of genes responsible for the content of salicylates. Thanks to this, the breeding cycle of a new variety is shortened, there is no need to wait for the harvest of plants. Hybrids arise from a combination of the best parental genotypes.
The result of the work of scientists from the Department of Plant Breeding and Seed Production in Olsztyn is the registration of the first willow variety called Bona, which grows on an experimental plantation in Bałdy. The research project aims to create new varieties with even higher salicylate content.
According to the recommendations of the European Pharmacopoeia, i.e. the list of quality requirements, willow bark obtained for the production of medicinal preparations should contain at least 1,5 percent. salicylic glycosides. In the case of the material obtained during the experiments by scientists from Olsztyn, the percentage of these compounds is much higher and reaches 11%. (PAP)
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