Root neck of Norway spruce as a source of bioactive lignans and stilbenes

Abstract Bioactive compounds of acetone-water extracts obtained from the root neck (RN) of Norway spruce (Picea abies [L.] Karst.) have been studied for the first time. RN samples were divided into different zones and cut, and wood and bark were extracted separately with acetone-water. The extracts were analyzed by gas chromatography-mass spectrometry. The extractives have a tissue-specific distribution. Several lignans were identified in the heartwood. High concentrations (10%) of hydroxymatairesinol were found from the heartwood at the lowermost part of the RN. The inner part of the bark contained the highest concentrations of stilbene glucosides (20%), which were present in the outer bark only to a minor extent (0.2%). Pressurized hot water extraction was also applied and was found to be effective in separating lignans from biomass. Norway spruce roots and stumps are usually utilized for gaining bioenergy. The results presented here show that these abundant residual materials of forest economy may be a valuable source of highly bioactive compounds such as the lignan hydroxymatairesinol and stilbenes.</jats:p