The presence of microcystins in the coastal waters of Nigeria, from the Bights of Bonny and Benin, Gulf of Guinea

Autor: Osasere Abike Omoruyi, Solomon Isagba, Mathias Ahii Chia, Jeffrey Uyi Ogbebor, Timothy E Unusiotame-Owolagba, Adriana Sturion Lorenzi, Medina Omo Kadiri, Maria do Carmo Bittencourt-Oliveira
Rok vydání: 2020
Předmět:
Zdroj: Environmental Science and Pollution Research. 27:35284-35293
ISSN: 1614-7499
0944-1344
Popis: Microcystins (MCs) are the most studied toxins of cyanobacteria in freshwater bodies worldwide. However, they are poorly documented in coastal waters in several parts of the world. In this study, we investigated the composition of cyanobacteria and the presence of microcystins (MCs) in several coastal aquatic ecosystems of Nigeria. Direct morphological analysis revealed that members of the genus Oscillatoria were dominant with five species, followed by Trichodesmium with two species in Nigerian coastal waters. Oso Ibanilo had the highest cyanobacterial biomass (998 × 103 cells/L), followed by Rivers Ocean (156 × 103 cells/L). Except for the Cross River Ocean, cyanobacteria were present in all the investigated aquatic ecosystems. Ten (10) out of twenty water bodies examined had detectable levels of MCs. Furthermore, genomic DNA analysis for the mcyE gene of microcystin synthetase (mcy) cluster showed identities higher than 86% (query coverage > 96%) with toxic strains of cyanobacteria in all the samples analyzed. Also, the sequences of samples matched those of uncultured cyanobacteria from recreational lakes in Southern Germany. Our findings indicate that the presence of toxic cyanobacteria in coastal waters of Nigeria is of public and environmental health concern.
Databáze: OpenAIRE