Chemical composition of ultrasonic-assisted n-hexane extracts of Sideritis scardica Grieseb. and Sideritis raeseri Boiss. & Heldr. (Lamiaceae) from Macedonia and Albania

Chemical composition of n-hexane extracts obtained from dried over-ground parts of two species of Sideritis, S. scardica Grieseb. and S. raeseri Boiss. & Heldr. (Lamiaceae) was analyzed using GC/FID/MS. The collection of plants was made on different locations in the western part of Macedonia and the southern part of Albania, comprising twelve different samples of plant material. The ultrasonic-assisted extraction process was used for preparation of the n-hexane extracts yielded 0.73-3.33 % and 9.11-10.44 % of extracts for S. scardica and S. raeseri, respectively. Over one hundred constituents of the extracts were identified, belonging to several classes of components: diterpenes, hydrocarbons, dominantly present in each of the extracts, followed by fatty acids, aliphatic and aromatic alcohols, sterols, triterpene alcohols, and monoterpenes and sesquiterpenes, which were found in much smaller amounts or only in traces. The most abundant constituents of the extracts of both species of Sideritis were two diterpene components, both with M=286, which were not fully identified. Large percentages of nonacosane (1.71-12.22% and 7.46-19.68% for S. scardica and S. raeseri, respectively) and hentriacontane (4.48-20.79% and 8.09-30.31 % for S. scardica and S. raeseri, respectively) were also found in the extracts of both species.