Next Article in Journal
Venom Ontogeny in the Mexican Lance-Headed Rattlesnake (Crotalus polystictus)
Next Article in Special Issue
Effects of Dietary Astaxanthin Supplementation on Energy Budget and Bioaccumulation in Procambarus clarkii (Girard, 1852) Crayfish under Microcystin-LR Stress
Previous Article in Journal
The Antioxidant Gallic Acid Inhibits Aflatoxin Formation in Aspergillus flavus by Modulating Transcription Factors FarB and CreA
Previous Article in Special Issue
Development of Time-Resolved Fluoroimmunoassay for Detection of Cylindrospermopsin Using Its Novel Monoclonal Antibodies
Article

The Presence of Toxic and Non-Toxic Cyanobacteria in the Sediments of the Limpopo River Basin: Implications for Human Health

1
Department of Hydrology and Water Resources, School of Environmental Sciences, University of Venda, Thohoyandou 0950, South Africa
2
Council for Scientific and Industrial Research, Natural Resources and the Environment, Stellenbosch 7600, South Africa
3
Department of Biochemistry, School of Mathematical and Natural Sciences, University of Venda, Thohoyandou 0950, South Africa
*
Author to whom correspondence should be addressed.
Toxins 2018, 10(7), 269; https://doi.org/10.3390/toxins10070269
Received: 10 May 2018 / Revised: 19 June 2018 / Accepted: 21 June 2018 / Published: 3 July 2018
(This article belongs to the Special Issue Cyanobacteria and Cyanotoxins: New Advances and Future Challenges)
The presence of harmful algal blooms (HABs) and cyanotoxins in drinking water sources poses a great threat to human health. The current study employed molecular techniques to determine the occurrence of non-toxic and toxic cyanobacteria species in the Limpopo River basin based on the phylogenetic analysis of the 16S rRNA gene. Bottom sediment samples were collected from selected rivers: Limpopo, Crocodile, Mokolo, Mogalakwena, Nzhelele, Lephalale, Sand Rivers (South Africa); Notwane (Botswana); and Shashe River and Mzingwane River (Zimbabwe). A physical-chemical analysis of the bottom sediments showed the availability of nutrients, nitrates and phosphates, in excess of 0.5 mg/L, in most of the river sediments, while alkalinity, pH and salinity were in excess of 500 mg/L. The FlowCam showed the dominant cyanobacteria species that were identified from the sediment samples, and these were the Microcystis species, followed by Raphidiopsis raciborskii, Phormidium and Planktothrix species. The latter species were also confirmed by molecular techniques. Nevertheless, two samples showed an amplification of the cylindrospermopsin polyketide synthetase gene (S3 and S9), while the other two samples showed an amplification for the microcystin/nodularin synthetase genes (S8 and S13). Thus, these findings may imply the presence of toxic cyanobacteria species in the studied river sediments. The presence of cyanobacteria may be hazardous to humans because rural communities and farmers abstract water from the Limpopo river catchment for human consumption, livestock and wildlife watering and irrigation. View Full-Text
Keywords: cyanobacteria; cyanotoxins; nutrient enrichment; akinetes; harmful algal blooms; PCR; phylogenetic analyses cyanobacteria; cyanotoxins; nutrient enrichment; akinetes; harmful algal blooms; PCR; phylogenetic analyses
Show Figures

Figure 1

MDPI and ACS Style

Magonono, M.; Oberholster, P.J.; Shonhai, A.; Makumire, S.; Gumbo, J.R. The Presence of Toxic and Non-Toxic Cyanobacteria in the Sediments of the Limpopo River Basin: Implications for Human Health. Toxins 2018, 10, 269. https://doi.org/10.3390/toxins10070269

AMA Style

Magonono M, Oberholster PJ, Shonhai A, Makumire S, Gumbo JR. The Presence of Toxic and Non-Toxic Cyanobacteria in the Sediments of the Limpopo River Basin: Implications for Human Health. Toxins. 2018; 10(7):269. https://doi.org/10.3390/toxins10070269

Chicago/Turabian Style

Magonono, Murendeni, Paul J. Oberholster, Addmore Shonhai, Stanley Makumire, and Jabulani R. Gumbo 2018. "The Presence of Toxic and Non-Toxic Cyanobacteria in the Sediments of the Limpopo River Basin: Implications for Human Health" Toxins 10, no. 7: 269. https://doi.org/10.3390/toxins10070269

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop