Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Jan 24;11(5):1752-1762.
doi: 10.1021/acssuschemeng.2c05823. eCollection 2023 Feb 6.

Ionic Liquid-Assisted Selective Extraction and Partitioning of Biomolecules from Macroalgae

Edgar Suarez Garcia  1 , Carlota F Miranda  2 , M Teresa Cesario  2 , Rene H Wijffels  1   3 , Corjan van den Berg  1 , Michel H M Eppink  1
Affiliations

Ionic Liquid-Assisted Selective Extraction and Partitioning of Biomolecules from Macroalgae

Edgar Suarez Garcia et al. ACS Sustain Chem Eng. .

Abstract

Macroalgae are a promising feedstock for several industries due to their large content of proteins and carbohydrates and the high biomass productivities. A novel extraction and fractionation concept based on ionic liquids (ILs) using Ulva lactuca as model organism is presented. Biomolecules are first extracted by means of IL-assisted mechanical shear, followed by two-phase partitioning or ultrafiltration in order to fractionate proteins and carbohydrates and to recover the IL. Ethyl methyl imidazolium dibutyl phosphate ([Emim][DBP]) is strongly selective to proteins, leading to extraction yields up to 80.4% for proteins and 30.7% for carbohydrates. The complete process, including extraction and ultrafiltration, allowed protein recovery of up to 64.6 and 15.4% of the carbohydrates in the retentate phase, while a maximum of 85.7% of the IL was recovered in the permeate phase. The native structure of the extracted proteins was preserved during extraction and fractionation as shown by gel electrophoresis. Selective extraction of proteins from macroalgae under non-denaturing conditions using ILs followed by the recovery of IL using ultrafiltration is for the first time reported. The proposed extraction-fractionation approach is simple and can be potentially applied for the biorefinery of macroalgae at the commercial scale.

PubMed Disclaimer

Conflict of interest statement

The authors declare no competing financial interest.

Figures

Figure 1
Figure 1
Block diagram for the IL-mediated extraction process, followed by IL recovery or phase partitioning and subsequent IL recovery via ultrafiltration.
Figure 2
Figure 2
(A) Extraction yields for proteins (gray bars) and carbohydrates (white bars) for samples after conventional extraction methods or ATPE. Data correspond to average values and corresponding standard deviation as error bars (n = 3). (B) Native gel electrophoresis (M: Marker, T: Top, B: Bottom; white arrows indicate main protein bands). (C) Four-phase system developed after ATPE.
Figure 3
Figure 3
(A) Extraction yields for proteins (gray bars) and carbohydrates (white bars) in samples after treatment with ILs (40 wt %) and bead milling. Data correspond to average values, and corresponding standard deviations are shown as error bars (n = 3, experiments conducted in triplicate). (B) Experimental samples of algal biomass treated with ILs. Extraction conducted at room temperature and t ≈ 10 min.
Figure 4
Figure 4
Effect of the concentration of [Emim][DBP] on the extraction of proteins (gray bars) and carbohydrates (white bars). The data corresponds to averages, and the errors bars are the standard deviation (n = 2). Lowercase letters indicate statistically equal means at 95% confidence.
Figure 5
Figure 5
(A) Phase diagram for the system [Emim][DBP]-K2HPO4 with detail of the operation points S1 and S2. (B) Algal samples treated with [Emim][DBP] followed by the addition of K2HPO4 for phase induction and biomolecule partitioning. (C) Overall yields for protein (gray bars) and carbohydrates (white bars) after phase formation and partitioning. Data presented here are the average values and errors bars as standard deviation (n = 2). Dotted bars are assigned for system S2.
Figure 6
Figure 6
Native gel electrophoresis of samples before and after filtration studies (Pe: Permeate, Re: Retentate, M: Marker; white arrows indicate main protein bands).
Figure 7
Figure 7
Overview of processes for the recovery of proteins (filled markers) and carbohydrates (open markers) from green macroalgae. Circles represent published data, and squares represent data from the present study.
See this image and copyright information in PMC

References

    1. Henchion M.; Hayes M.; Mullen A.; Fenelon M.; Tiwari B. Future Protein Supply and Demand: Strategies and Factors Influencing a Sustainable Equilibrium. Foods 2017, 6, 53.10.3390/foods6070053. - DOI - PMC - PubMed
    1. Bharathiraja B.; Chakravarthy M.; Ranjith Kumar R.; Yogendran D.; Yuvaraj D.; Jayamuthunagai J.; Praveen Kumar R.; Palani S. Aquatic biomass (algae) as a future feed stock for bio-refineries: A review on cultivation, processing and products. Renewable Sustainable Energy Rev. 2015, 47, 634–653. 10.1016/j.rser.2015.03.047. - DOI
    1. Tenorio A. T.; et al. Trends in Food Science & Technology Understanding di ff erences in protein fractionation from conventional crops , and herbaceous and aquatic biomass - Consequences for industrial use. Trends Food Sci. Technol. 2018, 71, 235–245. 10.1016/j.tifs.2017.11.010. - DOI
    1. Chan C. X.; Ho C. L.; Phang S. M. Trends in seaweed research. Trends Plant Sci. 2006, 11, 165–166. 10.1016/j.tplants.2006.02.003. - DOI - PubMed
    1. Van Hal J. W.; Huijgen W. J. J.; López-Contreras A. M. Opportunities and challenges for seaweed in the biobased economy. Trends Biotechnol. 2014, 32, 231–233. 10.10.1016/j.tibtech.2014.02.007. - DOI - PubMed