Dissertação de Mestrado

Strategies to produce Single-cell protein from hydrolysates of industrial residues of Gelidium corneum using GRAS microorganisms in one or two bioreactors in series

Diogo Jacinto Marques2025

Informações chave

Autores:

Diogo Jacinto Marques (Diogo Jacinto Marques)

Orientadores:

Maria Teresa Ferreira Cesário Smolders (Maria Teresa Ferreira Cesário Smolders); Marília Clemente Velez Mateus (Marília Clemente Velez Mateus)

Publicado em

25/03/2025

Resumo

As the global population continues to rise, the demand for alternative food/feed sources in particular protein sources, has become increasingly urgent. This study explores the use of hydrolysates of industrial residues of the red seaweed Gelidium corneum, as a low-cost, sugar-rich feedstock for fermentation aiming at single cell protein (SCP) production. Residues after agar extraction used in this work were composed of 27.3 ± 3.0 g/100g DW carbohydrates and 36.0 ± 1.2 g/100g DW protein. Enzymatic hydrolysis with cellulases yielded 91.6% of the total releasable glucose. Glucose-rich hydrolysates were used as carbon-source to microbial cultures aiming at SCP production. Bench-scale bioreactor assays were conducted using either a Lactobacillus consortium (4LAB) or a mixed culture of Saccharomyces cerevisiae and 4LAB. Slightly higher levels of lactic acid (LA) (110 g/L) were produced compared to 4LAB fermentation (101 g/L). To enhance protein content, an innovative sequential fermentation was developed using the 4LAB consortium in the first bioreactor and Corynebacterium glutamicum in the second bioreactor, feeding on the LA produced by 4LAB. Although C. glutamicum exhibited poor tolerance to high LA concentrations, it produced a fermented product containing SCP with 15.7 g protein/ 100 g DW. All fermented products exhibited increased protein bioaccessibility when compared to the raw Gelidium residues and increased antioxidant activity was exhibited by the 4LAB fermented product. These findings highlight the potential of using fermentation for the valorisation of a marine waste stream to produce a product with enhanced nutritional properties.

Detalhes da publicação

Autores da comunidade :

Orientadores desta instituição:

Domínio Científico (FOS)

industrial-biotechnology - Biotecnologia Industrial

Idioma da publicação (código ISO)

eng - Inglês

Acesso à publicação:

Acesso Embargado

Data do fim do embargo:

27/12/2025

Nome da instituição

Instituto Superior Técnico