A new method for protein extraction from sea lettuce (Ulva fenestrata) via surfactants and alkaline aqueous solutions
Journal article, 2025

Alternative protein sources such as seaweed can help relieve the pressure on land-based protein supply. This proof-of-concept study developed an extraction method to recover soluble and lipophilic proteins from the seaweed Ulva fenestrata. The method consisted of processing U. fenestrata with 0.1–0.5 % aqueous Triton X-114 solution and reprocessing the pellet with an alkaline aqueous solution. Then, the solubilized proteins were precipitated via acidification. The new method extracted 3.4-times more protein, measured as total amino acids, compared to the control with two alkaline aqueous extraction cycles. Triton disrupted the chloroplasts and likely solubilized lipophilic membrane proteins as supported by microstructure and polypeptide pattern analysis. Triton-derived protein extracts contained lipids inside the precipitates/aggregates and were richer in fatty acids typical of photosynthetic membranes. The higher extraction yields are proposed to result from membrane charge neutralization upon acidification, triggering interactions between the membrane lipids and their subsequent precipitation with the lipophilic membrane protein.

Thylakoid membrane protein

Sustainable food protein

Macroalgae

Solubility

Precipitation

Detergent

Author

João Pedro Trigo

Chalmers, Life Sciences, Food and Nutrition Science

Sophie Steinhagen

University of Gothenburg

Kristoffer Stedt

University of Gothenburg

A. Krona

RISE Research Institutes of Sweden

Simone Verhagen

Wageningen University and Research

Henrik Pavia

University of Gothenburg

Mehdi Abdollahi

Chalmers, Life Sciences, Food and Nutrition Science

Ingrid Undeland

Chalmers, Life Sciences, Food and Nutrition Science

Food Chemistry

0308-8146 (ISSN) 1873-7072 (eISSN)

Vol. 464 141839

Seaweed as a vehicle for nutrients in a circular food chain - innovative steps to accomplish a protein shift (CirkAlg)

Formas (2018-01839), 2018-12-01 -- 2021-11-30.

Subject Categories

Biological Sciences

Chemical Engineering

Chemical Sciences

DOI

10.1016/j.foodchem.2024.141839

PubMed

39541858

More information

Latest update

11/19/2024