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. 2025 Jun 17;17(6):307.
doi: 10.3390/toxins17060307.

Growth Dynamics and Toxin Production of Pseudo-nitzschia Species Isolated from the Central Adriatic Sea

Tina Tomašević  1   2 , Jasna Arapov  1 , Ivana Ujević  1 , Tina Bonačić  1   2 , Mia Bužančić  1 , Antonija Bulić  1 , Sanda Skejić  1 , Romana Roje-Busatto  1 , Živana Ninčević Gladan  1
Affiliations

Growth Dynamics and Toxin Production of Pseudo-nitzschia Species Isolated from the Central Adriatic Sea

Tina Tomašević et al. Toxins (Basel). .

Abstract

The marine diatoms Pseudo-nitzschia spp. are globally distributed primary producers, with certain species capable of producing neurotoxin domoic acid (DA), causing amnesic shellfish poisoning (ASP). This study investigates the toxicity and growth rates of Pseudo-nitzschia species isolated from aquaculture areas in the Central Adriatic Sea. A total of 54 strains from eight species were analysed, with strains originating from four different study sites. Growth rates and toxin production were examined across different growth phases in other species and strains. Most species, including P. allochrona, P. calliantha, P. delicatissima, P. fraudulenta, P. galaxiae, P. mannii, and P. multistriata, did not produce DA at any growth phase. The only species that showed toxin production, at 18 °C was P. pseudodelicatissima (0.0007-0.0250 pg cell-1). Notably, the majority of P. pseudodelicatissima strains were toxic in the decay phase and some strains showed continuous toxin production throughout all growth phases. The highest growth rates for the analysed species were recorded in strains of P. delicatissima, which also exhibited the highest cell abundance (8.19 × 105 cell mL-1), followed by the species P. allochrona, P. mannii and P. pseudodelicatissima.

Keywords: Adriatic Sea; domoic acid; growth rate; toxic diatoms.

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Conflict of interest statement

The authors declare no conflicts of interest.

Figures

Figure 1
Figure 1
Growth rates of all analysed strains for each species. The centre line represents the median value, the lower edge of the box the lower quartile; the upper edge of the box the upper quartile. The T-shaped whiskers go to the last point, which is still within 1.5 times the interquartile range. If there are no outliers, the whiskers present the maximum or minimum values.
Figure 2
Figure 2
Cell abundance (cell mL−1) by growth phase for all analysed strains of Pseudo-nitzschia species. (A) P. allochrona; (B) P. calliantha; (C) P. delicatissima; (D) P. fraudulenta; (E) P. galaxiae; (F) P. mannii; (G) P. multistriata; (H) P. pseudodelicatissima. The scale is different for the P. delicatissima due to high cell abundance. The centre line represents the median value, the lower edge of the box the lower quartile; the upper edge of the box the upper quartile. The T-shaped whiskers go to the last point, which is still within 1.5 times the interquartile range. If there are no outliers, the whiskers present the maximum or minimum values.
Figure 3
Figure 3
LC–MS/MS chromatogram obtained by LC–MS/MS analysis of the Pseudo-nitzschia pseudodelicatissima strain K357ps at the stationary growth phase (growth phase 3), containing a domoic acid peak at retention time 2.603 min (black trace). The red trace represents the domoic acid standard included for comparison.
Figure 4
Figure 4
(A) Cell abundance (cell mL−1) through growth phases of strains showing toxin production in at least three growth phases. (B) Mean domoic acid concentration (pg cell−1) in replicate samples during the growth phases of strains that produced the toxin in at least three distinct phases.
Figure 5
Figure 5
The study sites: (A) V—Velebit Channel, (B) S—Šibenik Channel, (C) K—Kaštela Bay, (D) M—Mali Ston Bay.
See this image and copyright information in PMC

References

    1. Lelong A., Hégaret H., Soudant P., Bates S.S. Pseudo-nitzschia (Bacillariophyceae) species, domoic acid and amnesic shellfish poisoning: Revisiting Previous Paradigms. Phycologia. 2012;51:168–216. doi: 10.2216/11-37.1. - DOI
    1. Dong H.C., Lundholm N., Teng S.T., Li A., Wang C., Hu Y., Li Y. Occurrence of Pseudo-nitzschia species and associated domoic acid production along the Guangdong Coast, South China Sea. Harmful Algae. 2020;98:101899. doi: 10.1016/j.hal.2020.101899. - DOI - PubMed
    1. Lundholm N., Bernard C., Churro C., Escalera L., Hoppenrath M., Iwataki M., Larsen J., Mertens K., Moestrup Ø., Murray S., et al., editors. (2009 Onwards). IOC-UNESCO Taxonomic Reference List of Harmful Micro Algae. [(accessed on 2 March 2025)]; Available online: https://www.marinespecies.org/hab.
    1. Lundholm N., Christensen A.L., Olesen A.K.J., Beszteri B., Eggers S.L., Krock B., Altenburger A. Diversity, toxicity, and distribution of potentially toxic diatoms in Antarctic waters––with description of Pseudo-nitzschia meridionalis sp. nov. and P. glacialis sp. nov. Harmful Algae. 2024;139:102724. doi: 10.1016/j.hal.2024.102724. - DOI - PubMed
    1. von Dassow P., Mikhno M., Percopo I., Orellana V.R., Aguilera V., Álvarez G., Araya M., Cornejo-Guzmán S., Llona T., Mardones J.I., et al. Diversity and toxicity of the planktonic diatom genus Pseudo-nitzschia from coastal and offshore waters of the Southeast Pacific, including Pseudo-nitzschia dampieri sp. nov. Harmful Algae. 2023;130:102520. doi: 10.1016/j.hal.2023.102520. - DOI - PubMed

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