The Effect of Artificial Sweeteners on the Growth and Metabolic Activity of Nitrosopumilus maritimus strain SCM1

Identifier:  TFG:9015

Handle: https://hdl.handle.net/20.500.11797/TFG9015

Authors:  Martinez Calado, Elisa

Abstract:
Artificial sweeteners are increasingly detected in aquatic environments, yet their effect on marine microorganisms remains largely unknown. This study investigated the impact of these micropollutants on the growth and metabolic activity of Nitrosopumilus maritimus, a marine ammonia-oxidizing archaeon with a key role in the marine nitrogen cycle. Cultures were exposed to different concentrations of five artificial sweeteners (saccharin, sucralose, aspartame, acesulfame K and cyclamate), and nitrite accumulation was used as an indicator of growth and ammonia oxidation activity. Results showed that the culture exposed to 3000 ng/L of sucralose exhibited growth inhibition. A subsequent screening experiment was conducted with concentrations between 1000 ng/L and 3000 ng/L. No significant inhibition was observed under any of the experimental conditions, suggesting the initial result may have been due to experimental variability or an outlier. These findings indicate that N. maritimus can sustain normal activity and growth in presence of artificial sweeteners at environmentally relevant concentrations.