https://pubs.rsc.org/en/content/articlepdf/2019/NP/C8NP00092A

Marine natural products.

Bioaerosols in the Earth system: Climate, health, and ecosystem interactions

This study explores the potential use of sulfate radical-based advanced oxidation technologies (SR-AOTs) for the degradation of the naturally occurring hepatotoxin, microcystin-LR (MC-LR). The generation of sulfate radicals was achieved by activation of the oxidants persulfate (PS) and peroxymonosulfate (PMS) through electrophilic transition metal cations (Ag+ and Co2+, respectively), radiation (UV 300  − has similar redox potential to hydroxyl radical (HO ), to the best of our knowledge, SR-AOTs have not been tested for the degradation of cyanotoxins. In this study, PMS was activated very efficiently with Co2+ at neutral pH and increasing catalyst concentration resulted in dramatic increase of the initial rates of degradation that reached a plateau for CCo(II) ≥ 1 mg. Based on the optimum pH conditions for each system, the efficiency order is Co2+/PMS > Fe2+/H2O2 ≫ Ag+/PS, which we believe is associated with the energy of the lower unoccupied molecular orbital of the oxidants. When UV (300  Since, the UV lamps used in the study emit light at a range of wavelengths (300

Degradation of microcystin-LR using sulfate radicals generated through photolysis, thermolysis and e− transfer mechanisms

The cyanobacteria or "blue-green algae", as they are commonly termed, comprise a diverse group of oxygenic photosynthetic bacteria that inhabit a wide range of aquatic and terrestrial environments, and display incredible morphological diversity. Many aquatic, bloom-forming species of cyanobacteria are capable of producing biologically active secondary metabolites, which are highly toxic to humans and other animals. From a toxicological viewpoint, the cyanotoxins span four major classes: the neurotoxins, hepatotoxins, cytotoxins, and dermatoxins (irritant toxins). However, structurally they are quite diverse. Over the past decade, the biosynthesis pathways of the four major cyanotoxins: microcystin, nodularin, saxitoxin and cylindrospermopsin, have been genetically and biochemically elucidated. This review provides an overview of these biosynthesis pathways and additionally summarizes the chemistry and toxicology of these remarkable secondary metabolites.

https://www.mdpi.com/1660-3397/8/5/1650/pdf

S. Pflugmacher

Papers

Ecotoxicological effects of selected cyanobacterial secondary metabolites: a short review.