Determinação de metabólitos lipídicos em microalgas

• Ano de defesa: 2021
• Autor(a) principal: Fagundes, Mariane Bittencourt
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Santa Maria; Brasil; Ciência e Tecnologia dos Alimentos; UFSM; Programa de Pós-Graduação em Ciência e Tecnologia dos Alimentos; Centro de Ciências Rurais
• Palavras-chave em Português: Esteróis; Bioatividade; Extrações emergentes; SFE; GXL; Ultrassom; Microalgae; Phormidium autumnale; Sterols; Bioactivity; Emerging extractions; Ultrasound; Green chemistry; CNPQ::CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS
• Link de acesso: http://repositorio.ufsm.br/handle/1/25301

Microalgae are microorganisms with a complex and little explored metabolome, and can therefore be considered a rich source ofmaterialfor omicsstudies. Currently,society islookingfor compounds that have bioactivity and can be applied as nutraceuticals and also as an input for pharmaceutical industries. Among the microalgae cataloged and studied, the strain of Phormidium autumnale stands out as little explored in general, the latest studies report carotenoids and lipids, however, the study of sterolomics. Therefore, the objective of this workwas to explore the sterolomic profile of microalgae and also to verify the influence of these metabolites against neurodegenerative diseases. As a result, articles and book chapters (published or in the process of publication) were generated, which were organized in this document into chapters. Chapters 1 to 3 refer to review article and book chapters, and chapters4 and 5 refer to publications purchased in research journals. Chapter 1: “Development of a sterol method in microalgae: a brief review of isolation and bioactive potential” (review articlein the process of publication); Chapter 2:"Sterols from microalgae” (book chapter/publicationcompleted); Chapter 3: “Sterols Biosynthesis in Algae” (book chapter/publication completed);Chapter 4: “Green microsaponification-based method for gas chromatography of sterol and squalene in cyanobacterial biomass” (research article/publication completed); Chapter 5: “Phytosterol-rich compressed fluid extracts from Phormidium autumnale cyanobacteria with neuroprotective potential” (research article/publication completed). Finally, the results of these scientific productions indicate that the cyanobacterium Phormidium autumnale can be considered a source of sterols due to the concentrations found, which are: 5–18 mg kg−1 stigmasterol, 6 mg kg−1 cholesterol, and 3 mg kg−1 of β sitosterol mg kg−1, obtained from amicro-saponification, and that, depending on the forms of extraction, the extract can show bioactivity, as observed using emerging extraction technologies such as supercritical fluid and ethanol/gas-expanded solvent (GXL). The results were obtained as the best optimization conditions:266.3 bar pressure, and 7% ethanol. The biochemical inhibition values (IC50) acquired were: 65.80 μg mL−1 for acetylcholinesterase, 58.20 μg mL−1 for lipoxygenase inhibition, and 7.40 μg mL−1 for antioxidant activity. Soon, these results indicate that the extract has bioactivity against neurodegenerative diseases.