Research Article

A preliminary study on a strain of Pseudo-nitzschia delicatissima (Cleve) Heiden isolated from the Golden Horn Estuary (Sea of Marmara, Türkiye): Morphology, phylogeny and toxicity

Volume: 43 Number: 4 November 11, 2026
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A preliminary study on a strain of Pseudo-nitzschia delicatissima (Cleve) Heiden isolated from the Golden Horn Estuary (Sea of Marmara, Türkiye): Morphology, phylogeny and toxicity

Abstract

The diatom Pseudo-nitzschia delicatissima (Cleve) Heiden, 1928 is known a potential producer of domoic acid (DA), a neurotoxin which can cause Amnesic Shellfish Poisoning (ASP). The specific objectives of this study are to reveal the identification, based on morphological characterization via Scanning Electron Microscopy (SEM) and molecular phylogeny, and toxicity of a P. delicatissima strain (DEB132304) isolated from the Golden Horn Estuary (Sea of Marmara, Türkiye). SEM analysis revealed characteristic frustule features consistent with the general morphological description of P. delicatissima. Molecular and phylogenetic analyses based on ribosomal gene sequences from the LSU and ITS regions further supported the identification of the strain as P. delicatissima, with congruent phylogenetic placements obtained from both markers. The strain was harvested during the stationary growth phase and analysed for DA and its isomers; however, none were detected above the limit of detection (LOD) of 0.39 pg cell-1. Considering that the Pseudo-nitzschia species have previously formed blooms in the study area, regular monitoring of these species is essential. Further studies investigating the ecophysiological characteristics of different strains of P. delicatissima isolated from the same study area and the influence of environmental factors on DA production are needed to better understand its toxinological potential.

Keywords

Supporting Institution

This study was financed by Istanbul University (Coordination Unit of Scientific Research Projects). Project numbers: FBA-2022-239324

Project Number

Project numbers: FBA-2022-239324 and FDK-2023-39989

Ethical Statement

No specific ethical approval was required for this study.

Thanks

We greatly acknowledge technical support of Thomas Max (AWI) for toxin analysis.

References

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Details

Primary Language

English

Subjects

Biochemistry and Cell Biology (Other), Hydrobiology, Ecology (Other), Aquaculture and Fisheries (Other)

Journal Section

Research Article

Publication Date

November 11, 2026

Submission Date

August 31, 2026

Acceptance Date

October 30, 2026

Published in Issue

Year 2026 Volume: 43 Number: 4

APA
Şemin, S., Taş, S., Dursun, F., Durmuş, T., Sezgin, R., Balcı, M., Krock, B., & Ergül, H. A. (2026). A preliminary study on a strain of Pseudo-nitzschia delicatissima (Cleve) Heiden isolated from the Golden Horn Estuary (Sea of Marmara, Türkiye): Morphology, phylogeny and toxicity. Ege Journal of Fisheries and Aquatic Sciences, 43(4), 431-440. https://doi.org/10.12714/egejfas.43.4.12
AMA
1.Şemin S, Taş S, Dursun F, et al. A preliminary study on a strain of Pseudo-nitzschia delicatissima (Cleve) Heiden isolated from the Golden Horn Estuary (Sea of Marmara, Türkiye): Morphology, phylogeny and toxicity. EgeJFAS. 2026;43(4):431-440. doi:10.12714/egejfas.43.4.12
Chicago
Şemin, Sebahat, Seyfettin Taş, Fuat Dursun, et al. 2026. “A Preliminary Study on a Strain of Pseudo-Nitzschia Delicatissima (Cleve) Heiden Isolated from the Golden Horn Estuary (Sea of Marmara, Türkiye): Morphology, Phylogeny and Toxicity”. Ege Journal of Fisheries and Aquatic Sciences 43 (4): 431-40. https://doi.org/10.12714/egejfas.43.4.12.
EndNote
Şemin S, Taş S, Dursun F, Durmuş T, Sezgin R, Balcı M, Krock B, Ergül HA (November 11, 2026) A preliminary study on a strain of Pseudo-nitzschia delicatissima (Cleve) Heiden isolated from the Golden Horn Estuary (Sea of Marmara, Türkiye): Morphology, phylogeny and toxicity. Ege Journal of Fisheries and Aquatic Sciences 43 4 431–440.
IEEE
[1]S. Şemin et al., “A preliminary study on a strain of Pseudo-nitzschia delicatissima (Cleve) Heiden isolated from the Golden Horn Estuary (Sea of Marmara, Türkiye): Morphology, phylogeny and toxicity”, EgeJFAS, vol. 43, no. 4, pp. 431–440, Nov. 2026, doi: 10.12714/egejfas.43.4.12.
ISNAD
Şemin, Sebahat - Taş, Seyfettin - Dursun, Fuat - Durmuş, Turgay - Sezgin, Rabia - Balcı, Muharrem - Krock, Bernd - Ergül, Halim Aytekin. “A Preliminary Study on a Strain of Pseudo-Nitzschia Delicatissima (Cleve) Heiden Isolated from the Golden Horn Estuary (Sea of Marmara, Türkiye): Morphology, Phylogeny and Toxicity”. Ege Journal of Fisheries and Aquatic Sciences 43/4 (November 11, 2026): 431-440. https://doi.org/10.12714/egejfas.43.4.12.
JAMA
1.Şemin S, Taş S, Dursun F, Durmuş T, Sezgin R, Balcı M, Krock B, Ergül HA. A preliminary study on a strain of Pseudo-nitzschia delicatissima (Cleve) Heiden isolated from the Golden Horn Estuary (Sea of Marmara, Türkiye): Morphology, phylogeny and toxicity. EgeJFAS. 2026;43:431–440.
MLA
Şemin, Sebahat, et al. “A Preliminary Study on a Strain of Pseudo-Nitzschia Delicatissima (Cleve) Heiden Isolated from the Golden Horn Estuary (Sea of Marmara, Türkiye): Morphology, Phylogeny and Toxicity”. Ege Journal of Fisheries and Aquatic Sciences, vol. 43, no. 4, Nov. 2026, pp. 431-40, doi:10.12714/egejfas.43.4.12.
Vancouver
1.Sebahat Şemin, Seyfettin Taş, Fuat Dursun, Turgay Durmuş, Rabia Sezgin, Muharrem Balcı, Bernd Krock, Halim Aytekin Ergül. A preliminary study on a strain of Pseudo-nitzschia delicatissima (Cleve) Heiden isolated from the Golden Horn Estuary (Sea of Marmara, Türkiye): Morphology, phylogeny and toxicity. EgeJFAS. 2026 Nov. 11;43(4):431-40. doi:10.12714/egejfas.43.4.12