Volatile organic compounds of Tilia cordata Mill. from Serbia, in terms of ecosystem services

It is considered that different plant organic compounds, known as phytoncides are creditable for positive effects of Forest therapy on human health. Ongoing pandemic has also put these compounds in research focus considering potential use for novel corona virus treatment. This research was conducted in order to examine the potential of Tilia cordata Mill. considering volatile organic compounds (VOCs) content for the use in Forest therapy. In order to determine qualitative and quantitative content of phytoncides, as well the variability among genotypes growing in the same environmental conditions, leaf samples from genotypes of T. cordata were collected from the Fruška gora (Serbia) during 2019. VOCs determined in fresh herbal material were analyzed by HeadspaceGC/MS and VOCs determined in essential oil were obtained by GC/MS. The results showed the presence of 17 different phytoncides (monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons, oxygenated sesquiterpenes, aliphatic compounds and diterpenes) in all tested genotypes. According to the mean values of the obtained results, the most abundant classes of phytoncides among the examined genotypes were monoterpene hydrocarbons (87.05), followed by aliphatic compounds (36.59) and oxygenated sesquiterpenes (34.60). The highest coefficient of variation (CV) among phytoncide content in tested T. cordata genotypes has been observed within oxygenated monoterpenes (43.12%), sesquiterpene hydrocarbons (28.18%), and diterpenes (27.04%). Some individual monoterpene hydrocarbons, such as o-cymene (19.92%) and a-pinene (17.40%) had the highest CV in terms of its presence in analyzed genotypes. In addition, the principal component analysis (PCA) showed more notable clustering within the VOCs determined in essential oil in comparison to VOCs determined in fresh herbal material. Considering the phytoncide content detected in T. cordata leaves, this species has high potential for the use in human health improvement within Forest therapy.