Anais CBFic - Volume 1 - 2018

Sociedade Brasileira de Ficologia - SBFic

Publicado em 26/11/2018

Volume 1 - 2019

Título do Trabalho

GROWTH AND METABOLIC PERFORMANCE OF NITZSCHIA PALEA UNDER DIFFERENT SILICATE SOURCES

Autores

RINAMARA MARTINS ROSA, ALINE DUARTE BATISTA, MARCELO GOMES MARçAL VIEIRA VAZ, MARIANA MACHADO, ALAN SANTOS MAGALHãES, WAGNER L. ARAúJO , ADRIANO NUNES-NESI

Modalidade

Resumo

Área Temática

4 USO SUSTENTáVEL DE ALGAS E OUTROS

Data de Publicação

26/11/2018

País da Publicação

Brasil

Idioma da Publicação

Português

Página do Trabalho

http://sbfic.org.br/anais_show/108

ISSN

Aguardando...

Palavras-Chave

diatom, biofuel, waste, biomass

Resumo

Usage of diatoms for commercial purposes, such as the production of biomass rich in high-added value compounds or the use of silicon from their frustules, has been the focus of numerous researches. Due to these organisms' characteristics, such as the presence of siliceous cell wall, its cultivation depends on the supply of micro and macro nutrients and a significant concentration of silicate. This nutritional requirement hinders the low production cost of these organisms, making it necessary the development of alternative ways to support this demand. In this context, this work assessed the usage of carbonized rice hulls and iron aggregates (commercial fertilizer Agrosilício Plus®), as silicate source, in different concentrations to cultivate two strains (BR006 and BR022) of the freshwater diatom Nitzschia palea. The experiment was carried out in growing room under ligh intensity of 90 μmol photons m-2 s-1, photoperiod of 16:8 (ligh:dark), temperature of 24ºC and constant shaking (110 rpm). Each strain was submitted to 7 treatments: BG-11 (standard medium), with addition of 6 mg. L-1 of Na2SiO3 (control) and BG-11 supplemented with (0, 1.38, 6.95, 13.8, 20.84, 27.79 mg L-1). Rice hulls supplementation was efficient in the cultivation of both strains, with an increase of 30% in biomass productivity compared to the control culture medium. The strains BR006 and BR022 showed the highest productivity in the treatment with 30 g·L-1 of carbonized rice hull, yielding 0.9056 g·L-1 and 0.8914 g·L-1 of biomass, respectively. This results are either associated to silicon supply and to other micro and macronutrients present in the material. The culture with steel aggregate, although did not show an increase in the biomass productivity, having its productivity about 40-50% lower than the control culture medium, did not present cell mortality and the yield of the accumulated compounds had percentages close to the control culture medium, with lipidic productivity above 30% (m/m). Both sources were able to provide soluble silicate to the cultures, allowing their maintenance or an increase of productivity. The patterns of accumulated compounds for the different sources, combined with the different dosages, indicates that it is possible to modulate the content of storage compounds by manipulating nutritional traits. Taken together, these results indicate that the sources and treatments applied are potential for large scale low cost cultivationof Nitzschia palea strains. Acknowledgment: FAPEMIG, CNPq, CAPES.