Kalaitzidou Maria P, Nannou Christina I, Lambropoulou Dimitra A, Papageorgiou Konstantinos V, Theodoridis Alexandros M, Economou Vangelis K, Giantsis Ioannis A, Angelidis Panagiotis G, Kritas Spyridon K, Petridou Evanthia J
National Reference Laboratory for Marine Biotoxins, Department of Food Microbiology, Biochemical Control, Residues, Marine Biotoxins and other water toxins, Directorate of Veterinary Center of Thessaloniki, Ministry of Rural Development and Food, Limnou 3A, 54627, Thessaloniki, Greece.
Laboratory of Environmental Pollution Control, Department of Chemistry, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece.
J Biol Res (Thessalon). 2021 Mar 10;28(1):8. doi: 10.1186/s40709-021-00139-4.
Microcystins are emerging marine biotoxins, produced by potentially toxic cyanobacteria. Their presence has been reported in aquatic animals in Greek freshwater, while data are few in marine environments. Since the climate change induces eutrophication and harmful algal blooms in coastal marine ecosystems affecting the public health, further research on microcystins' presence in marine waters is required. The aim of this study was to examine the potential presence of microcystins in mussels Mytilus galloprovincialis in the largest farming areas in Thermaikos gulf, in Northern Greece, and to investigate their temporal and spatial distribution, adding to the knowledge of microcystins presence in Greek Mediterranean mussels.
A 4-year microcystins' assessment was conducted from 2013 to 2016, in farmed Mediterranean mussels M. galloprovincialis, in five sampling areas in Thermaikos gulf, in northern Greece, where the 90% of the Greek mussels' farming activities is located. The isolation of potentially toxic cyanobacteria was confirmed by molecular methods. An initial screening was performed with a qualitative and quantitative direct monoclonal (DM) ELISA and results above 1 ng g were confirmed for the occurrence of the most common microcystins-RR, -LR and -YR, by Ultra High Performance Liquid Chromatography (UHPLC) coupled with a high- resolution mass spectrometer (HRMS) (Orbitrap analyzer). Microcystin-RR and microcystin-LR were detected, while the intensity of microcystin-YR was below the method detection limit. Most samples that exhibited concentrations above 1 ng g were detected during the warm seasons of the year and especially in spring. Results indicated an overestimation of the ELISA method, since concentrations ranged between 0.70 ± 0.15 ng g and 53.90 ± 3.18 ng g, while the confirmation denoted that the levels of microcystins were 6 to 22 times lower.
Microcystin-RR and microcystin-LR were detected for the first time in mussel M. galloprovincialis, harvested from farms in Thermaikos gulf, in Central Macedonia, Greece. Their presence was linked to potentially toxic cyanobacteria. Bioaccumulation was observed in digestive gland, while the concentrations in muscles were found extremely low. Samples with levels above 1 ng g were observed mostly during spring, confirming the seasonal distribution of microcystins. The comparison of the results by the ELISA and the LC-Orbitrap MS method indicated an overestimation of concentration by the ELISA method.
微囊藻毒素是新出现的海洋生物毒素，由具有潜在毒性的蓝藻产生。希腊淡水水体中的水生动物体内已报道有微囊藻毒素存在，而海洋环境中的相关数据较少。由于气候变化导致沿海海洋生态系统富营养化和有害藻华，影响公众健康，因此需要进一步研究海水中微囊藻毒素的存在情况。本研究的目的是检测希腊北部塞尔迈湾最大养殖区的养殖贻贝（Mytilus galloprovincialis）中微囊藻毒素的潜在存在情况，并调查其时间和空间分布，以增加对希腊地中海贻贝中微囊藻毒素存在情况的了解。
2013年至2016年对希腊北部塞尔迈湾五个采样区域养殖的地中海贻贝（M. galloprovincialis）进行了为期4年的微囊藻毒素评估，希腊90%的贻贝养殖活动都位于该区域。通过分子方法确认了具有潜在毒性的蓝藻的分离。使用定性和定量直接单克隆（DM）酶联免疫吸附测定（ELISA）进行初步筛选，对于最常见的微囊藻毒素-RR、-LR和-YR的存在，通过超高效液相色谱（UHPLC）结合高分辨率质谱仪（HRMS）（轨道阱分析仪）确认了高于1 ng/g的结果。检测到了微囊藻毒素-RR和微囊藻毒素-LR，而微囊藻毒素-YR的强度低于方法检测限。大多数浓度高于1 ng/g的样本是在一年中的温暖季节检测到的，尤其是在春季。结果表明ELISA方法存在高估情况，因为浓度范围在0.70±0.15 ng/g至53.90±3.18 ng/g之间，而确认结果表明微囊藻毒素水平低6至22倍。
在希腊中马其顿地区塞尔迈湾养殖场收获的贻贝（M. galloprovincialis）中首次检测到微囊藻毒素-RR和微囊藻毒素-LR。它们的存在与具有潜在毒性的蓝藻有关。在消化腺中观察到生物累积，而肌肉中的浓度极低。大多在春季观察到水平高于1 ng/g的样本，证实了微囊藻毒素的季节性分布。ELISA方法和液相色谱-轨道阱质谱法结果的比较表明ELISA方法高估了浓度。
