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
. 2019 Aug 20:2019:6424651.
doi: 10.1155/2019/6424651. eCollection 2019.

Optimization and Identification of Antioxidant Peptide from Underutilized Dunaliella salina Protein: Extraction, In Vitro Gastrointestinal Digestion, and Fractionation

Enqin Xia #  1 , Lu Zhai #  1 , Zhigang Huang  1 , Hairong Liang  1 , Hui Yang  1 , Gang Song  1 , Weiqiao Li  1 , Huanwen Tang  1
Affiliations

Optimization and Identification of Antioxidant Peptide from Underutilized Dunaliella salina Protein: Extraction, In Vitro Gastrointestinal Digestion, and Fractionation

Enqin Xia et al. Biomed Res Int. .

Abstract

DPPH• scavenging peptides (<3kDa) from underutilized Dunaliella salina protein were obtained by the following successive treatment, i.e., ultrasound extraction, simulated in vitro gastrointestinal digestion hydrolyzation, and membrane ultrafiltration classification. The optimal condition for ultrasound-assisted extraction was an ultrasound wave with 800 W of power treating a mixture of 60 mL of 1.0 mol L-1 NaOH and 2 g algae powder for 15 min. A high correlation (r=0.8146) between DPPH• scavenging activity and yield of the intact peptides showed their antioxidant capacity. Simulated in vitro digestion assay resulted in excellent DPPH• scavenging activity of the total peptide, amounting to (86.5 ± 10.1)%, comparing with the nondigestion samples at (46.8 ± 6.5)%. After fractionation, the 500-1000 Da fraction exhibited the highest DPPH• scavenging activity (81.2 ± 4.0)%, increasing 1.5 times due to digestion. Then, the 500-1000 Da fraction was analyzed by RPLC-Q Exactive HF mass spectrometer, and 4 novel peptides, i.e., Ile-Leu-Thr-Lys-Ala-Ala-Ile-Glu-Gly-Lys, Ile-Ile-Tyr-Phe-Gln-Gly-Lys, Asn-Asp-Pro-Ser-Thr-Val-Lys, and Thr-Val-Arg-Pro-Pro-Gln-Arg, were identified. From these amino acid sequences, hydrophobic residues accounted for 56%, which indicated their high antioxidant property. The results indicated that underutilized protein of Dunaliella salina could be a potential source of antioxidative peptides through simulated in vitro gastrointestinal digestion.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Extraction and optimization of peptide from the crude extract.
Figure 2
Figure 2
Effect of ultrasound radiation on the DPPH• scavenging activities of peptide.
Figure 3
Figure 3
The relationship of the yield and DPPH• scavenging activity of peptide.
Figure 4
Figure 4
The second mass spectrogram of the identified peptides.
Figure 5
Figure 5
The ratio of amino acids in the novel peptides.
See this image and copyright information in PMC

References

    1. Leanderson P., Faresjö Å. O., Tagesson C. Green tea polyphenols inhibit oxidant-induced DNA strandbreakage in cultured lung cells. Free Radical Biology & Medicine. 1997;23(2):235–242. doi: 10.1016/S0891-5849(96)00590-4. - DOI - PubMed
    1. Leeb E., Holder A., Letzel T., Cheison S. C., Kulozik U., Hinrichs J. Fractionation of dairy based functional peptides using ion-exchange membrane adsorption chromatography and cross-flow electro membrane filtration. International Dairy Journal. 2014;38(2):116–123. doi: 10.1016/j.idairyj.2013.12.006. - DOI
    1. Narváez-Rivas M., Vu N., Chen G., Zhang Q. Off-line mixed-mode liquid chromatography coupled with reversed phase high performance liquid chromatography-high resolution mass spectrometry to improve coverage in lipidomics analysis. Analytica Chimica Acta. 2017;954:140–150. doi: 10.1016/j.aca.2016.12.003. - DOI - PMC - PubMed
    1. Suja K. P., Abraham J. T., Thamizh S. N., Jayalekshmy A., Arumughan C. Antioxidant efficacy of sesame cake extract in vegetable oil protection. Food Chemistry. 2004;84(3):393–400. doi: 10.1016/S0308-8146(03)00248-6. - DOI
    1. Hsu C., Tain Y. Regulation of nitric oxide production in the developmental programming of hypertension and kidney disease. International Journal of Molecular Sciences. 2019;20(3):p. 681. doi: 10.3390/ijms20030681. - DOI - PMC - PubMed