From Inundations to Golden Opportunity: Turning Holopelagic <i>Sargassum</i> spp. into a Valuable Feed Ingredient through Arsenic Removal
Karla Itzel Cisneros-Ramos,
Montserrat Gutiérrez-Castañeda,
Edén Magaña-Gallegos,
Alejandra G. Villegas-Pañeda,
Luz Verónica Monroy-Velázquez,
María Guadalupe Barba-Santos,
Martha Gabriela Gaxiola-Cortés,
Brigitta I. van Tussenbroek
Affiliations
Karla Itzel Cisneros-Ramos
Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
Montserrat Gutiérrez-Castañeda
Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
Edén Magaña-Gallegos
Unidad Académica de Sistemas Arrecifales-Puerto Morelos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos 77580, Quintana Roo, Mexico
Alejandra G. Villegas-Pañeda
Laboratorio Institucional de Química, El Colegio de la Frontera Sur (ECOSUR), Av. Centenario Km 5.5, Chetumal 77014, Quintana Roo, Mexico
Luz Verónica Monroy-Velázquez
Unidad Académica de Sistemas Arrecifales-Puerto Morelos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos 77580, Quintana Roo, Mexico
María Guadalupe Barba-Santos
Unidad Académica de Sistemas Arrecifales-Puerto Morelos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos 77580, Quintana Roo, Mexico
Martha Gabriela Gaxiola-Cortés
Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
Brigitta I. van Tussenbroek
Unidad Académica de Sistemas Arrecifales-Puerto Morelos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos 77580, Quintana Roo, Mexico
For over a decade, numerous Greater Caribbean and Western African coasts have received enormous masses of holopelagic Sargassum spp. (sargasso). A promising use of this beached biomass as a feed ingredient in the animal industry is restricted by its high arsenic (As) content. This proof of concept aimed to demonstrate that simple, low-cost processes involving hot water (either fresh or seawater) and/or citric acid can remove arsenic from the sargasso. Sargasso collected from a Mexican Caribbean beach in December 2023 had a total arsenic level of 62.2 mg/kg, which decreased to 7.2 mg/kg after treatment with hot freshwater (90 °C for 15 min), and then further decreased to 0.8 mg/kg when followed up with a citric acid treatment. Sargasso collected in March 2024 had total arsenic of 89 mg/kg, which was lowered to 2.6 mg/kg by applying hot freshwater and citric acid sequentially. Employing only citric acid reduced the arsenic concentration to 8.0 mg/kg, while treating the sargasso only with hot seawater reduced the As level to 10.1 mg/kg. Thus, simply using hot water, either fresh or seawater, lowered the arsenic levels to acceptable levels for the animal feeding sector. These straightforward and potentially cost-effective methods may transform the restraint of high arsenic contents into a valuable opportunity to use these seaweeds as animal feed.