Abstract
This study was a part of the ForestSpecs FP7 EU project. The aim of this project was to utilize the readily available, large volume and low price wood residues from the wood processing industry. The first part of this work involved a comparative study of three extraction techniques, shaking, soxhlet and microwave assisted extraction. The microwave extraction was found to be the most suitable method, as it allowed the results to be achieved with reduced level of solvents, lower energy consumption and faster processing time. The phytochemical investigation of six forestry species: Pinus sylvestris, Larix gmelinii, L. sibirica, L. sukaczewii, L. decidua, and Populus tremula was performed. This included many steps such as grinding, extraction of plant materials and separation, isolation and purification of a variety of compounds with potential use in pharmaceutical, cosmetic and also pest management applications. A total of ninety-three compounds were identified, with thirty-two being isolated from more than one source. Of these, four have not been described previously and are shown below. Compound 13 was isolated from L. gmelinii and compounds 32, 33 and 37 were isolated from L. sukaczewii. Components from the species investigated have been identified using 1D, 2D NMR and IR spectroscopy, mass spectrometry and optical rotation measurements. The extracts and purified compounds were submitted to the consortium screening programme. The thirteen bark extracts of the species investigated were tested for cytotoxic and apoptotic activity using the LDH and MTT assays, as well as Western blot analysis of protein p53. In both, A-375 human melanoma cells and CV1-P fibroblast cells, the following bark extracts showed selective cytotoxic effects against A-375 cancerous cells: L. gmelinii DCM (LGD) and P. sylvestris DCM (PSD), EtOAc (PSE) and MeOH (PSM) extracts. Further investigation demonstrated that L. gmelinii DCM and EtOAc and P. sylvestris DCM extracts induced the translocation of the p53 protein into the nucleus. This approach proved the significance of the use of natural products as chemopreventive agents and cancer therapeutics.