Environmental concentrations of copper nanoparticles affect vital functions in Ankistrodesmus densus

Autor(es)

Barreto, Daniela Mariano ^[1] ; Tonietto, Alessandra Emanuele ^[2] ; Lombardi, Ana Teresa ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos UFSCar, Dept Bot, Rodovia Washington Luis Km 235, BR-13565905 Sao Carlos, SP - Brazil

^[2] Univ Estado Santa Catarina UDESC, Chem Dept, Rua Paulo Malschitzki 200, BR-89219710 Joinville, SC - Brazil

• Tipo de documento: Artigo Científico
• Fonte: AQUATIC TOXICOLOGY; v. 231, FEB 2021.
• Citações Web of Science: 0

Resumo

Nanoparticles (NPs) have unique properties, leading to their widespread application in industry, consequently increasing their concentration in aquatic ecosystems. Although environmentally significant concentrations are still low, they tend to increase because of the intense use, posing into risk microalgae communities. Microalgae are primary producers that support food chains in aquatic ecosystems; thus factors that interfere with their physiology can be propagated throughout the food web. The present research investigated the effects of copper nanoparticles (Cu-NPs) in the physiology of a cosmopolitan green microalgae, Ankistrodesmus densus. Here, we focused on environmental NPs levels, so an ample Cu-NPs range was used, 0.3-635 mu g L-1. Considering that NPs dissolve into the medium releasing their constituent material, free Cu2+ ions were determined and considered as surrogate for NPs concentration, which varied from 2.1 x 10(9) to 8.4 x 10(-)(9) mol L-1. The experiment was based in 72 h Cu-NPs exposure, and to access the physiology of A. densus, we monitored population growth, photochemistry of photosynthesis and the content of cell biomolecules (total proteins, carbohydrates and lipids). The results showed that 2.1 x 10(-9) mol L-1 free Cu2+ was enough to decrease growth rate, but 2.5x higher Cu was necessary to affect the photosynthetic parameters. Inorganic carbon fixation rate calculated by absolute electron transport rates was affected. Considering cell biomolecules, total proteins accumulated at 6.5 x 10(-9) and kept increasing up to 8.4 x mol L-1 free Cu2+. Because this was not related to biomass formation, we suggest a possible association with cell detoxification mechanisms. The most clear finding that emerged from this study is that environmental Cu-NPs concentrations affect vital functions in the green microalgae A. densus. An implication of this is the possibility of facing problems related to a increase of NPs in aquatic ecosystems in the near future. (AU)

• Processo FAPESP: 18/07988-5 - Bioprospecção, caracterização e otimização de microalgas brasileiras para a biofixação de CO2 e produção de biomoléculas de importância comercial
• Beneficiário: Ana Teresa Lombardi
• Modalidade de apoio: Auxílio à Pesquisa - Temático