Effects of ultraviolet radiation removal on algal communities in three high-elevation Brazilian (ultra)oligotrophic lakes

Autor(es)

de Oliveira, Danielly Guilherme ^[1] ; Schneider, Geniane ^[2] ; Itokazu, Ana Gabriela ^[2] ; Costa, Giulia Burle ^[3] ; Rorig, Leonardo Rubi ^[2] ; Simonassi, Jose Carlos ^[4] ; de Barros, Marcelo Paes ^[5] ; Figueroa, Felix L. ^[6] ; Bonomi-Barufi, Jose ^{[1, 2]} ; Guimaraes, Melina ^[7]

Afiliação do(s) autor(es)

^[1] Univ Fed Santa Catarina, Bot Dept, Postgrad Program Biol Algae Plants & Fungi, BR-88040900 Florianopolis, SC - Brazil

^[2] Univ Fed Santa Catarina, Dept Microbiol Immunol & Parasitol, Postgrad Program Biotechnol & Biosci, BR-88040900 Florianopolis, SC - Brazil

^[3] Univ Fed Santa Catarina, Bot Dept, Postgrad Program Ecol, BR-88040900 Florianopolis, SC - Brazil

^[4] Nucleo Estudos Mar, Biol Sci Ctr, Sea Studies Nucleus, Campus Reitor Joao David Ferreira Lima, BR-88040900 Florianopolis, SC - Brazil

^[5] Cruzeiro do Sul Univ, Inst Phys Act Sci & Sports ICAFE, Interdisciplinary Program Hlth Sci, BR-01506000 Sao Paulo - Brazil

^[6] Malaga Univ, Gribe Hutchinson Expt Ctr, Inst Blue Biotechnol & Dev IBYDA, San Julian Campus, Malaga 29071 - Spain

^[7] Univ Catolica Brasilia, Biol Sci Fac, EPCT, QS 7, Lt 1, BR-71966700 Brasilia, DF - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PHYCOLOGIA; v. 60, n. 5, SI OCT 2021.
• Citações Web of Science: 1

Resumo

Ultraviolet (UV) radiation is a major constraint to aquatic photosynthetic organisms. Freshwater algae dwelling in natural high altitudinal ponds and lakes must tolerate high UV radiation exposure, especially in oligotrophic waters. Here, we investigated the in situ physiological short-term response of three algal communities to UV removal in lakes at high-elevation in Brazil, by measuring photosynthesis, carotenoid and phenolic contents, nutrient concentration and antioxidant enzymatic activities. Rancho Queimado (RQ), Lagoa do Roncador (LR) and Lagoa Bonita (LB), located in southern and central Brazil, were classified as oligo and ultraoligotrophic and presented species-rich algal communities dominated by species of the class Zygnematophyceae. The algal communities presented different short-term metabolic strategies to circumvent the stressful effects of the UV, influenced by species composition. At RQ, photosynthesis was negatively affected by UV removal, suggesting that photoprotection may be triggered by this radiation; at this site, the algae relied mainly on an efficient superoxide dismutase response. LR algae exhibited a higher contribution of catalase but prioritized the non-enzymatic antioxidant defences (phenolics and carotenoids) as their background and primary barrier against reactive oxygen species, which contributed to the development of higher net photosynthesis than that of the other sites and showed no variation to light treatments. LB algae appeared to be impaired by the increase in the temperature and highly variable irradiance throughout the day, which affected the net photosynthesis and activity of antioxidant enzymes. However, similar to LR, carotenoids and phenolic compounds acted as protagonists against oxidative damage. (AU)

• Processo FAPESP: 17/06032-2 - Estratégias bioquímicas, fisiológicas e transcriptômicas para o estudo da relação entre carotenóides, estresse oxidativo e qualidade de frutas cítricas
• Beneficiário: Marcelo Paes de Barros
• Modalidade de apoio: Bolsas no Exterior - Pesquisa