Evaluation of food grade solvents for lipid extraction and impact of storage temperature on fatty acid composition of edible seaweeds Laminaria digitata (Phaeophyceae) and Palmaria palmata (Rhodophyta)

Abstract

This study evaluated the impact of different food- and non-food grade extraction solvents on yield and fatty acid composition of the lipid extracts of two seaweed species (Palmaria palmata and Laminaria digitata). The application of chloroform/methanol and three different food grade solvents (ethanol, hexane, ethanol/hexane) revealed significant differences in both, extraction yield and fatty acid composition. The extraction efficiency, in terms of yields of total fatty acids (TFA), was in the order: chloroform/methanol>ethanol>hexane>ethanol/hexane for both species. Highest levels of polyunsaturated fatty acids (PUFA) were achieved by the extraction with ethanol. Additionally the effect of storage temperature on the stability of PUFA in ground and freeze-dried seaweed biomass was investigated. Seaweed samples were stored for a total duration of 22months at three different temperatures (-20°C, 4°C and 20°C). Levels of TFA and PUFA were only stable after storage at -20°C for the two seaweed species.

In Vitro Antithrombotic Properties of Salmon (Salmo salar) Phospholipids in a Novel Food-Grade Extract

“…Similarly to the present study, using different solvents and extractions (either food-grade or conventional) in other marine sources (i.e., seaweed or microalgae) resulted in differences in the lipid yield [43,56] and the fatty acid composition (i.e., an EtOH-based food-grade extraction achieved an extract rich in PUFA in contrast to conventional methods) [43]. Furthermore, polar lipid fractions, rich in phospho- and sphingolipids, obtained from another food source (buttermilk) by using food-grade ethanol gave a higher yield than those obtained using non-food-grade solvents, while these food-grade extracted PL fractions exhibited strong antiproliferative bioactivities against several cancer cells, whereas the non-food-grade extracted lipid extracts and fractions did not provide any significant anti-proliferative activity in any of the tumour cell lines that were assessed [57].…”

“…To the best of our knowledge, anti-PAF and anti-thrombin activities of polar lipids derived from marine sources by environmentally clean food-grade extraction methods according to EU legislation without the use of organic toxic solvents such as chloroform and petroleum ether, have not previously been reported. However, there have been several studies that have evaluated the effect of using food-grade and non-food-grade extraction methods on the fatty acid composition of lipid extracts of marine origin, especially in phospholipids rich in PUFA such as EPA and DHA [41,42,43]. However, these studies did not focus on the bioactivities that such marine-derived PLs may possess.…”

Azorean macroalgae (Petalonia binghamiae, Halopteris scoparia and Osmundea pinnatifida) bioprospection: a study of fatty acid profiles and bioactivity

“…The lower melting point of PUFA explains this latitudinal effect. Moreover, the sun-drying process and storage at room temperature prior to arrival at the IPMA laboratory may have led to some degradation of the PUFAs, which are prone to oxidation and degradation (Schmid et al, 2016;Turan, 2018). Concerning P. binghamiae, a previous study on P. fascia reported a very similar relative FA profile (Khotimchenko, 1998).…”

“…On the whole, when taking into account the various seaweed taxonomic groups (including brown and red seaweeds), a balanced assessment must highlight the complexity of interacting seasonal, spatial and speciesspecific drivers affecting the FA composition of seaweeds, thus influencing their nutritional value and requiring consideration when natural stocks are harvested for high added-value commercial applications (Schmid et al, 2016).…”

Biorefinery of marine macroalgae into high-tech bioproducts: a review

“…This makes macroalgae lipids suitable and popular for use in nutraceuticals, pharmaceuticals, functional foods and cosmetics markets. Of course, in order to be applied in the health and food sectors, more research is required in order to evaluate the stability of these compounds in different conditions (Schmid et al 2016). Polyunsaturated fatty acids (PUFAs), for example, have in their chemical structure double bonds that can react with oxygen and this can affect the ω-3 quality.…”