# Skin Irritation-Associated Dinoflagellate Vulcanodinium rugosum Isolated from Cienfuegos Bay, Cuba: Toxin Profile and Cell Growth Characterization Under Laboratory Conditions

## TL;DR

This study examines the growth and toxin production of a dinoflagellate linked to skin irritation in Cuba, providing insights for monitoring and forecasting harmful algal blooms.

## Contribution

The study provides the first data on toxin profiles and growth characteristics of Vulcanodinium rugosum under controlled laboratory conditions.

## Key findings

- V. rugosum cells can grow under agitated conditions, similar to those with low hydrodynamic energy.
- Higher toxin levels were observed during exponential growth, with Portimine-A and pinnatoxin-F as dominant toxins.

## Abstract

Blooms of the marine dinoflagellate Vulcanodinium rugosum have been associated with skin lesion outbreaks in Cuba and elsewhere. In this study, cell growth and toxin production were investigated under laboratory-controlled conditions in two strains isolated from Cienfuegos Bay, Cuba. Strains were cultured with and without a mechanical agitation and toxins were analyzed at two stages of the culture growth (exponential and stationary). Although blooms in Cienfuegos Bay occur in a semi-enclosed system characterized by calm waters with no agitation, the results of this study suggest that V. rugosum cells may also exhibit growth capacity under agitated conditions, or in open waters, comparable to that observed in systems with low hydrodynamic energy. Higher toxin levels, as determined by liquid chromatography with mass spectrometry (LC-MS/MS), were detected after exponential growth. Portimine-A and pinnatoxin-F (PnTX-F) were the dominant toxins (up to 1.75 and 1.0 pg·cell−1, respectively). PnTX-E, -D and Portimine-B were also detected at minor concentrations. This study contributes the first data necessary for a proper interpretation of monitoring programs aiming to assess the impact of V. rugosum blooms, particularly when used alongside forecasting models.