The resulting reactive 1,4-dialdehyde
oxytoxin 2 (9) can be identified by liquid chromatography–mass spectrometry
and is unstable in the wounded tissue. Caulerpenyne transformation occurs
rapidly, and severe tissue damage caused degradation of more than 50% of the
stored caulerpenyne within 1 min in all three algae. Prevention of the enzymatic
reaction before extraction, by shock freezing the tissue with liquid nitrogen, was
used for the determination of the caulerpenyne content in intact algae. It gives
about twofold higher values compared to an established methanol extraction
protocol. The speed and mechanism of the wound-activated transformation, as
well as the caulerpenyne content in intact tissue of invasive and noninvasive
Caulerpa spp., are comparable. Thus, this enzymatic transformation, despite