On the basis of preliminary research, we have set a laboratory setting of five stage counter-current extraction to extract pinosylvins out of wood. As a source of pinosylvin, we used ground wood tissues of Scots pine (Pinus sylvestris L.) from different habitats in Slovenia. To simulate an industrial sample, we separately prepared homogenous mixture of milled tissues, knots and heartwood. The samples were extracted with pure distilled water, ethanol/H2O (50/50, 60/40 (v/v)) and acetone/H2O (95/5 (v/v)). Each cycle lasted for 15 minutes at boiling temperature of the solvent. Then the extraction efficiency was evaluated gravimetricaly. We used UV-VIS spectroscopy to determine the content of total phenols. By using HPLC analysis we determinated the content of pinosylvin (PS) and pinosylvin monomethyl ether (PSMME). Knots were a better source of pinosylvin than heartwood at all solvents used. The content of te observed compounds was the lowest in the case of extraction with pure water (knots <13 mg/g, heartwood <5 mg/g), higher in ethanolic extracts (knots <33 mg/g, heartwood <10 mg/g) and the highest when extracted with acetone (knots <35 mg/g, heartwood <10 mg/g). The ratio between PS and PSMME in water extracts is 1:1,5 and 1:3 when extracted with ethanol or acetone. The counter-current extraction is a suitable method for acquiring pinosylvin from pine wood.
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