Innovative Alternative Technologies to Extract Carotenoids from Microalgae and Seaweeds

Abstract

Marine microalgae and seaweeds (microalgae) represent a sustainable source of various bioactive natural carotenoids, including β-carotene, lutein, astaxanthin, zeaxanthin, violaxanthin and fucoxanthin. Recently, the large-scale production of carotenoids from algal sources has gained significant interest with respect to commercial and industrial applications for health, nutrition, and cosmetic applications. Although conventional processing technologies, based on solvent extraction, offer a simple approach to isolating carotenoids, they suffer several, inherent limitations, including low efficiency (extraction yield), selectivity (purity), high solvent consumption, and long treatment times, which have led to advancements in the search for innovative extraction technologies. This comprehensive review summarizes the recent trends in the extraction of carotenoids from microalgae and seaweeds through the assistance of different innovative techniques, such as pulsed electric fields, liquid pressurization, supercritical fluids, subcritical fluids, microwaves, ultrasounds, and high-pressure homogenization. In particular, the review critically analyzes technologies, characteristics, advantages, and shortcomings of the different innovative processes, highlighting the differences in terms of yield, selectivity, and economic and environmental sustainability.

Stability and extraction of bioactive sulfur compounds from Allium genus processed by traditional and innovative technologies

“…have been well documented, with respect both to its analytical (Calvey et al, 1998(Calvey et al, , 1997Rybak et al, 2004;Zalepugin et al, 2015) and quantitative recovery (Del Valle et al, 2012;Martin and Guyer, 2004;Sass-Kiss et al, 1998a, 1998bYe and Lai, 2012). SFE utilizes supercritical fluids, usually supercritical CO2, as the extraction solvent, which provides superior extraction efficiency, particularly useful for the selective extraction of targeted compounds in high purity (Poojary et al, 2016). SFE, unlike MAE and PLE, can be operated at mild conditions, which is advantageous in recovering thermally labile compounds.…”

“…Microwave radiation facilitates the evaporation of moisture inside cells, producing a higher pressure on the cell wall causing increased porosity and cell/tissue disruption, favouring the extraction of intracellular compounds from plant matrices (Périno et al, 2016;Poojary et al, 2016).…”

Enzymatic extraction of fucoxanthin from brown seaweeds

“…Other non‐conventional technologies have shown efficacy in the extraction of bioactive compounds from algae (Barba et al ., ). These include ultrafiltration by molecular weight cut‐off membrane filters (Zhu et al ., ), pulsed electric fields, supercritical fluids, microwave, ultrasound and accelerated solvent extraction (Barba, ; Poojary et al ., ). For example, Parniakov et al .…”

Microwave hydrogravity pretreatment of Sargassum muticum before solvent extraction of antioxidant and antiobesity compounds

“…Among the components in ethanolic extracts, probably fucoxanthin was the most active. This compound is the main carotenoid present in brown seaweed, with antitumoral, anti‐inflamatory, antiobesity and neuroprotective actions . Fucoxanthin inhibited intercellular lipid accumulation during adipocyte differentiation of three T3‐L1 cells; also its metabolite fucoxanthinol exhibited stronger suppressive effects on lipid accumulation and adipocyte differentiation .…”

“…This technique could also be combined with supercritical CO 2 extraction, with hydrothermal processing or with enzyme assisted extraction to fractionate Sargassum muticum biomass and to solubilise fucoidans and phlorotannins . Other assisted or intensified technologies to extract bioactives from seaweed have been reported . Nowadays, the trends in the extraction of natural compounds are oriented towards improved yields maintaining the bioactives content, reduction in energy and solvents, and recycling of byproducts .…”