Cylindrospermopsin is an emerging cyanotoxin that can lead to phytotoxicity through different mechanisms. The presence of CYN in irrigation waters is of concern due to potential accumulation in plants, increasing the risk of human exposure by the consumption of vegetables. In this case, it is proposed to evaluate the effects of CYN on a crop considered staple food in Colombia, such as Solanum tuberosum, group Phureja var Criolla Colombia, known as “yellow potato”. This work evaluates for the first time the effects of CYN in potato plants exposed to this toxin using two different irrigation systems, surface and sprinkler irrigation. The parameters evaluated were CYN bioaccumulation and biotransformation in different parts of the potato plants irrigated with water containing CYN at environmentally relevant concentrations (84.65, 33.80, 3.05 and 3.05 µg/L after first, second, and third to fourth applications, respectively) and changes in nutritional mineral content in tubers. For this purpose, the concentrations of CYN and its potential metabolites in leaves, stem, roots, and tubbers of the plants exposed to the toxin were determined by Ultra-high Performance Liquid Chromatography–MS/MS (UHPLC-MS/MS). Mineral content was determined by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). CYN bioaccumulation was detected only in aerial parts of plants with sprinkler irrigation. A total of 57 CYN metabolites were found, and the main differences obtained in CYN biotransformation are linked to tissues and exposure conditions. There are significant differences in levels of Ca, K, Mg, Na, P, Cu, Fe, Mn, and Zn in tubers depending on CYN treatment, with higher contents after surface irrigation, and lower content with sprinkler application. These results demonstrate that the exposure conditions are an important factor for the potential presence and effects of CYN in potato plants.

In tropical countries, the control of the mosquito Aedes aegypti is a public health priority due to its role as a vector of important viral diseases. Marine cyanobacteria are recognized as abundant sources of bioactive compounds, and they constitute a potential source of insecticides useful for controlling mosquito populations and preventing epidemic outbreaks. We collected 30 benthic cyanobacterial mats in Providencia and Rosario islands (in the Colombian Caribbean) belonging to the genera Phormidium, Symploca, Oscillatoria, Lyngbya, Pseudoanabaena, Leptolyngbya, Moorea, and Dapis. Fractions of organic extracts from the most abundant environmental samples were evaluated in three bioassays, assessing (i) larvicidal activity against A. aegypti, (ii) toxicity against the brine shrimp (Artemia salina) nauplii, and (iii) acetylcholinesterase inhibition. Non-polar fractions exhibited larvicidal activity. The polar fraction from one Dapis pleuosa extract showed larvicidal activity without being toxic against A. salina nauplii. Extracts from Moorea producens exhibited the greatest toxicity against A. aegypti larvae and A. salina nauplii. From 23 cultured cyanobacterial samples, only five grew under laboratory conditions and produced enough biomass to yield organic extracts. Of these, three extracts showed strong larvicidal activity, but only the extract from Phormidium tenue showed reduced toxicity against A. salina nauplii. We detected variation among the chemical profiles and larvicidal activity of cyanobacterial consortia depending on sites and dates of collection. Our findings suggest that despite variation in chemical profiles, extracts of marine benthic cyanobacteria can be further developed as effective control agents against insect vectors, in their larval stages. The culture of marine benthic cyanobacteria needs to be further explored to provide enough biomass leading to the identification of bioactive compounds with public health applications.