Salicilatų kiekio įvairovė Lietuvoje augančiuose gluosniuose

In natural dendroflora of Lithuania willow genus (Salix L.) is abundant in species amount. Its bark contains active materials which are known as possessing anti-inflammatory properties since former times. Bark extracts are contained in analgesic as well as antirheumatic preparations. Its therapeutic effectiveness is associated with salicine which turns into salicylic acid. Willow bark is a know phytotherapeutic precursor of aspirin. To use more natural and not synthetic materials in the 21st century the methods for extraction of active materials for medicine are being sought. Thus, the studies on plant groups possessing the most intense anti-inflammatory properties became urgent. The amount of salicin varies among different species. Acording to the European Pharmacopoea, minimal amount of 1,5% of salicin is required in Willow bark. The aim of the study was to investigate salicylates amount variation in willow bark of different Salix species growing in Lithuania. The studies were carried out using the routine methods of pharmacopeia. After extraction analysis was performed by high performance liquid chromatography (HPLC) method. The first step of study was made among 3 samples of each plant, colected at different growing period (1-st year autumn, 2-nd year autumn and 2-nd year spring). Comparison of the quantities of the salicylic derivatives depending upon age of the plant and time of collection shows, that plants at two years of growth and collected in autumn accumulate greatest amounts of active substances (approximately 25.0% increase) when comparing with the 1 year old plants and material collected at spring season. The second experimental part was made among 32 species of willow collected in autumn of 2 years old plants. The results of this study shows, that there is striking differences in salicylic derivatives amount among different Salix species ( from 0,04% (Salix viminalis “Americana”) to 12,06% (Salix acutifolia). The amount of salicin is very low and these species are not recommended to be used for treatment. It is important to consider season of the year and age of the plant during collection of Willow bark. (Plants at two years of growth and collected in the autumn accumulate greatest amounts of active substances.) Other studies are required to evaluate amounts of other compounds (flavanoids, tannins or salicin esters), which may contribute to the overall effect while salicylate levels are to low to explain therapeutic activity