Microalgas em sistemas de piscicultura: aspectos ecofisiológicos e aplicações sustentáveis.

• Ano de defesa: 2022
• Autor(a) principal: Militão, Frederico Pacheco
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Doutorado em Biologia Vegetal; Centro de Ciências Humanas e Naturais; UFES; Programa de Pós-Graduação em Biologia Vegetal
• Palavras-chave em Português: Cultivo de microalgas; Meta análise; Bioprodutos; subject.br-rjbn; Agronomia
• Link de acesso: http://repositorio.ufes.br/handle/10/15770

The present study aims to evaluate the potential of microalgal biomass as a supplement in human and animal nutrition, from species isolated from psiculture tanks. Thus, 10 species, from 9 genera and two different divisions, were selected for biomass increase and laboratory-scale cultivation, isolated from fish farming systems in the Municipality of Registro, São Paulo, Brazil. The cultivation was of the batch type, without direct spraying of CO2, initial pH of 7 ± 0.05 and constant aeration of 3.5 L/min of air. The cultures were performed in quadruplicate in ASM1 (Cyanophyta) and BBM (Chlorophyta) medium, with an initial inoculum of 3.0 x105 Cel/mL-1, with the exception of S. hirsutum, a species with slower growth, which was of 3250 Cell/mL-1. The highest concentrations of total soluble carbohydrates, at the end of the experiment, were found in Chlorococcum sp. (12 mg/g MS), Kirchneriella sp. (11.3 mg/g MS) and M. wesenbergii (11.3 mg/g MS). Chlorococcum sp. also had the highest concentrations of fructose (12.7 mg/g DM), sucrose (16.6 mg/g DM) and starch (934 mg/g DM). S. javanensis (357 mg/g MS), C. pulchra (343 mg/g MS), S. hirsutum (336 mg/g MS), Chlorococcum sp (307 mg/g MS), H. reticulata (306 mg/g MS) g MS), Kirchneriella sp. (304 mg/g MS) and C. vulgaris (303 mg/g MS) did not differ statistically from each other in terms of total soluble protein concentration. Chlorococcum sp., Chlorella vulgaris and Kirchneriella sp., can be considered for use in supplementing animal feed. The high starch content found in the studied species, especially in Scenedesmus sp., Chlorococcum sp. and S. hirsutum, also indicates the potential use of this biomass in the production of bioethanol. The increase in nitrogen and salinity positively affects the accumulation of proteins, while high light intensities favor the synthesis of carbohydrates and lipids. The environmental conditions used in cultivation affect the biochemical composition of cultivated microalgae and the morphological type of the species can influence the adopted metabolic response. The knowledge and manipulation of these parameters, associated with the morphological type of the cultivated microalgae, is an effective way to obtain biomass with greater added, nutritional and commercial value.