Enzymatic Pre-Treatment Increases the Protein Bioaccessibility and Extractability in Dulse (Palmaria palmata)

Abstract

Several common protein extraction protocols have been applied on seaweeds, but extraction yields have been limited. The aims of this study were to further develop and optimize existing extraction protocols and to examine the effect of enzymatic pre-treatment on bioaccessibility and extractability of seaweed proteins. Enzymatic pre-treatment of seaweed samples resulted in a three-fold increase in amino acids available for extraction. Combining enzymatic pre-treatment with alkaline extraction resulted in a 1.6-fold increase in the protein extraction yield compared to a standard alkaline extraction protocol. A simulated in vitro gastrointestinal digestion model showed that enzymatic pre-treatment of seaweed increased the amount of amino acids available for intestinal absorption 3.2-fold. In conclusion, enzymatic pre-treatment of seaweeds is effective for increasing the amount of amino acids available for utilization and may thus be an effective means for increasing the utilization potential of seaweed proteins. However, both the enzymatic pre-treatment protocol and the protein extraction protocol need further optimization in order to obtain optimal cost-benefit and results from the in vitro gastrointestinal digestion model need to be confirmed in clinical models.

Protein Determination—Method Matters

“…Most foods are complex matrices, probably holding several of these protein classes and combining several solutes would probably optimize the extraction yield. In Mæhre et al [ 9 ] it was shown that combining H 2 O, 0.1 M NaOH and 3.5% NaCl at elevated temperature increased extraction yield compared to traditional extraction methods and this method was thus chosen as an example of a simpler protein extraction method in this study.…”

“…The salt/alkaline extraction was performed as described by Mæhre et al [ 9 ], with minor modifications. Briefly, 0.5 g of raw material was homogenized with 30 mL of 0.1 M sodium hydroxide (NaOH) in 3.5% sodium chloride (NaCl) using an UltraTurrax homogenizer (IKA Werke GmbH, Staufen, Germany).…”

Sequential bioprocessing of Ulva rigida to produce lignocellulolytic enzymes and to improve its nutritional value as aquaculture feed

“…H. Fernandes, et al Bioresource Technology 281 (2019) 277-285 availability in intestinal absorption (Maehre et al, 2016). Therefore, we can state that SSF is a viable biotechnological procedure that can be used as a biological treatment prior to the utilization of enzymes or other substances which aim to hydrolyse the cellulose content of U. rigida.…”

Macroalgae Derived Fungi Have High Abilities to Degrade Algal Polymers

“…Interest in macroalgae-based research has recently increased due to the rise in the world population and expected greater demand for food, feed, and fuel. One of the main challenges to efficiently extract valuable compounds from macroalgal biomass is structurally rigid and complex cell wall polysaccharides of seaweeds [2][3][4]. Cell wall polysaccharides of seaweeds are species dependent and significantly different from terrestrial plants.…”

“…Current methods of breaking up the macroalgal cell wall to extract valuable compounds are not optimal and have disadvantages of high energy consumption in case of mechanical methods, harsh conditions and toxicity during chemical extraction, and generation of side products and waste if high temperatures are used [17][18][19]. In contrast, it has been demonstrated that enzyme-assisted extraction holds big potential for development of targeted and sustainable processing of seaweeds [2,3,20,21]. Therefore, identification of enzymes involved in the specific degradation of algal cell walls is very important.…”