https://rinacional.tecnm.mx/jspui/handle/TecNM/1 Fri, 23 Oct 2026 20:02:55 GMT 2026-10-23T20:02:55Z https://rinacional.tecnm.mx:443/retrieve/37375ffd-6fc8-4e8c-94c1-4d07b72a5bf8/divulgación.png https://rinacional.tecnm.mx/jspui/handle/TecNM/1 https://rinacional.tecnm.mx/jspui/handle/TecNM/14248 Title: FITOPLANCTON POTENCIALMENTE NOCIVO EN EL MUELLE LA PUNTILLA, LAGUNA DE TÉRMINOS, SURESTE DEL GOLFO DE MÉXICO Authors: Poot Delgado, Carlos Antonio Description: In the coastal waters of the state of Campeche, basic information is needed on the presence of harmful phytoplankton species. For this purpose, in 2012 2013 over the course of a year, the water column was monitored monthly at the Puntilla dock, adjacent to Terminos Lagoon, SE Gulf of Mexico. Water temperature, salinity, pH, dissolved oxygen saturation and the abundance and composition of phytoplankton were determined. Both temperature and salinity were characterized by marked seasonal differences. The values of pH and oxygen suggested a predominance of photosynthetic activity. The pot entially harmful dinoflagellate Peridinium quinquecorne (up to 1.5x10 6 cells L 1 in the rainy season) and P. minimum (up to 2.3x10 6 cells L 1 in the northern winds season) were found to be blooming. Harmful phytoplankton species were observed in highest ab undances in the rainy and the northern winds seasons. Fri, 20 Nov 2015 00:00:00 GMT https://rinacional.tecnm.mx/jspui/handle/TecNM/14248 2015-11-20T00:00:00Z https://rinacional.tecnm.mx/jspui/handle/TecNM/14247 Title: Potentially harmful cyanobacteria in oyster banks of Términos lagoon, southeastern Gulf of Mexico. Authors: Poot Delgado, Carlos Antonio Description: Cyanobacteria inhabit hypersaline, marine and freshwater environments. Some toxic and non-toxic species can form harmful blooms. The aim of this study was to identify potentially harmful cyanobacterial species in the oyster banks of Términos Lagoon, the southeastern Gulf of Mexico. Six sample sites (up to 2-m depth) were monitored monthly from August 2012 to September 2013. Water temperature, salinity, pH, dissolved oxygen saturation (% DO), inorganic nutrients and abundance of cyanobacteria were determined. Temperature and salinity were characterized by marked seasonal differences (26.8 to 30.6 °C and 6.1 to 19.5, respectively). The pH values (ranging from 7.1 to 8.4) and the % DO (88.4 to 118.2 %) suggest a predominance of photosynthetic activity in the windy season (October-February). Elevated nutrient contents are associated with the period of increased river discharge, determined by water circulation and biogeochemical processes. Fourteen taxa were identified, of which Anabaena sp., Merismopedia sp., Oscillatoria sp. and Cylindrospermopsis cuspis produced blooms. Cyanobacterial abundances were on the order of magnitude of 106 cells L-1 in October 2012 at stations S1-S6, with an average value of 3.2x105 cells L-1 and a range of 2000 to 3.1x106 cells L-1 throughout the study period; however, they showed a remarkable absence during the windy season (October to January). Anabaena sp. and C. cuspis reached abundances of 1.9x106 and 1.3x106 cells L-1, respectively. The latter caused the temporary closure of oyster Crassostrea virginica harvesting for 15 days in October 2012. Sat, 04 Nov 2017 00:00:00 GMT https://rinacional.tecnm.mx/jspui/handle/TecNM/14247 2017-11-04T00:00:00Z https://rinacional.tecnm.mx/jspui/handle/TecNM/14246 Title: Effect of Different N:P Ratios on the Growth, Toxicity, and Toxin Profile of Gymnodinium catenatum (Dinophyceae) Strains from the Gulf of California Authors: Poot Delgado, Carlos Antonio Description: The harmful microalgae Gymnodinium catenatum is a unique naked dinoflagellate that produces paralytic shellfish poisoning toxins (PSTs). This species is common along the coasts of the Mexican Pacific and is responsible for paralytic shellfish poisoning, which has resulted in notable financial losses in both fisheries and aquaculture. In the Gulf of California, G. catenatum has been related to mass mortality events in fish, shrimp, seabirds, and marine mammals. In this study, the growth, toxin profiles, and toxin content of four G. catenatum strains isolated from Bahía de La Paz (BAPAZ) and Bahía de Mazatlán (BAMAZ) were evaluated with different N:P ratios, keeping the phosphorus concentration constant. All strains were cultivated in semi-continuous cultures (200 mL, 21.0 °C, 120 μmol photon m−2s−1, and a 12:12 h light-dark cycle) with f/2 + Se medium using N:P ratios of: 4:1, 8:1, 16:1, 32:1, and 64:1. Paralytic toxins were analyzed by HPLC with fluorescence detection. Maximum cellular abundance and growth were obtained at an N:P ratio of 64:1 (3188 cells mL−1 and 0.34 div day−1) with the BAMAZ and BAPAZ strains. A total of ten saxitoxin analogs dominated by N-sulfocarbamoyl (60–90 mol%), decarbamoyl (10–20 mol%), and carbamoyl (5–10 mol%) toxins were detected. The different N:P ratios did not cause significant changes in the PST content or toxin profiles of the strains from both bays, although they did affect cell abundance. Mon, 18 Jul 2022 00:00:00 GMT https://rinacional.tecnm.mx/jspui/handle/TecNM/14246 2022-07-18T00:00:00Z https://rinacional.tecnm.mx/jspui/handle/TecNM/14245 Title: Paralytic Shellfish Toxins of Pyrodinium bahamense (Dinophyceae) in the Southeastern Gulf of Mexico Authors: Poot Delgado, Carlos Antonio Description: In September and November 2016, eight marine sampling sites along the coast of the southeastern Gulf of Mexico were monitored for the presence of lipophilic and hydrophilic toxins. Water temperature, salinity, hydrogen potential, dissolved oxygen saturation, inorganic and phytoplankton abundance were also determined. Two samples filtered through glass fiber filters were used for the extraction and analysis of paralytic shellfish toxins (PSTs) by lateral flow immunochromatography (IFL), HPLC with post-column oxidation and fluorescent detection (FLD) and UHPLC coupled to tandem mass spectrometry (UHPLC-MS/MS). Elevated nutrient contents were associated with the sites of rainwater discharge or those near anthropogenic activities. A predominance of the dinoflagellate Pyrodinium bahamense was found with abundances of up to 104 cells L􀀀1. Identification of the dinoflagellate was corroborated by light and scanning electron microscopy. Samples for toxins were positive by IFL, and the analogs NeoSTX and STX were identified and quantified by HPLC-FLD and UHPLC-MS/MS, with a total PST concentration of 6.5 pg cell􀀀1. This study is the first report that confirms the presence of PSTs in P. bahamense in Mexican waters of the Gulf of Mexico. Tue, 22 Nov 2022 00:00:00 GMT https://rinacional.tecnm.mx/jspui/handle/TecNM/14245 2022-11-22T00:00:00Z