1,6-Dehydropinidine Is an Abundant Compound in (Pinaceae) Sprouts and 1,6-Dehydropinidine Fraction Shows Antibacterial Activity against Subsp. .

Knowledge about the defensive chemistry of coniferous trees has increased in recent years regarding a number of alkaloid compounds; in addition to phenolics and terpenes. Here, we show that Norway spruce ( (L.) H. Karst.), an important boreal zone tree species; accumulates 1,6-dehydropinidine (2-methyl-6-(2-propenyl)-1,6-piperideine) in its needles and bark. We reanalyzed previously published GC-MS data to obtain a full picture of 1,6-dehydropinidine in . 1,6-dehydropinidine appeared to especially accumulate in developing spring shoots. We used solid-phase partitioning to collect the alkaloid fraction of the sprouts and thin-layer chromatography to purify 1,6-dehydropinidine. The antibacterial properties of the 1,6-dehydropinidine fraction were tested using a broth microdilution method; with subsp. as a model organism. Based on our results 1,6-dehydropinidine is common in alkaloid extractions from (0.4 ± 0.03 mg g dw in mature needles) and it is especially abundant in young spruce shoots (2.7 ± 0.5 mg g dw). Moreover; 1,6-dehydropinidine extracted from sprouts showed mild antibacterial potential against subsp. (MIC 55 µg mL). The antibacterial activity of a plant compound thought of as an intermediate rather than an end-product of biosynthesis calls for more detailed studies regarding the biological function of these coniferous alkaloids.