Changes in apolar metabolites during in vitro organogenesis of Pancratium maritimum

Calli, shoot-clumps and regenerated plants were initiated from young fruits of Pancratium maritimum L. Their genetic stability was monitored by flow cytometry before chemical studies. Apolar metabolites (alkaloids extracted at pH > 7, free fatty acids and fatty alcohols, sterols etc.) were qualitatively and quantitatively analyzed by GC-MS. The results clearly demonstrated that alkaloid synthesis in P. maritimum is closely related with tissue differentiation. The highest amounts of alkaloids and presence of homolycorine and tazettine type compounds (end products of the biosynthetic pathway of the Amaryllidaceae alkaloids) were found in highly differentiated tissues. Galanthamine accumulated in the leaves of plantlets. The amount of hordenine, a protoalkaloid, is related with the ability of tissues to synthesize alkaloids. Saturated fatty acids were found in considerably higher levels in undifferentiated callus cultures and partially differentiated shoot-clumps than in regenerated plants. Mono- and dienoic fatty acids were found at higher levels in non-photosynthesizing tissues - calli, and in vitro and intact bulbs, while α-linolenic acid (trienoic acid) was found in higher amounts in the photosynthesizing leaves of shoot-clumps and regenerated plants than in bulbs and calli. Fatty alcohols were found mainly in leaves, while sterols tended to accumulate in photosynthesizing and undifferentiated tissues.