Purification and identification immunomodulatory peptide from rice protein hydrolysates

Figures & data

Figure 1. Schematic representation of purification and characterization approach used to identify immuno-active peptides from RPHs.

Figure 2. (A) Elution profile of RPHs on macroporous adsorption resin DA201-C. (B) Murine macrophage proliferation activity (SI) of separated fractions A1-A5. (C) Peptide yield of separated fractions A1–A5. (D) Hydrophobic value (kJ·mol⁻¹) of separated fractions A1-A5.

Figure 3. (A) Elution profile of A3 on strong acid cation resin 001 × 7 column. (B) Murine macrophage proliferation activity (SI) of the separated fractions A3-B1 to A3-B5.

Figure 4 (A) Chromatography of fraction A3-B3 on a Sephadex G-10 column. (B) Murine macrophage proliferation activity of each elution fraction. (C) and (D) Fraction A3-B3 molar mass distribution.

Figure 5 (A) Chromatography of the fraction A3-B3-C2 on a C18 column. The inset shows chromatography of fraction A3-B3-C2-D1 on a C18 column. (B) The murine macrophage proliferation activity of control (without fraction A3-B3-C2-D1), IgG (50 µg/mL) and different concentrations of fraction A3-B3-C2-D1.

Figure 6. Identification of molecular mass and amino acid sequences of purified peptides (fraction A3-B3-C2-D1-1) by HPLC-ESI-Q-TOF MS system.

Table 1. Reported immunomodulating peptides.

Amino acid sequence	Source	Hydrophobic amino acids	Basic amino acid
Tyr-Gly-Ile-Tyr-Pro-Arg	Rice Protein	Ile, Pro, Gly	Arg
Gly-Tyr-Pro-Met-Tyr-Pro-Leu-Pro-Arg	Rice Protein	Gly, Pro, Leu	Arg
Glu-Cys-Phe-Ser-Thr-Ala	Wheat germ globulin	Phe, Ala	−
Val-Glu-Pro-Ile-Pro-Tyr	Human casein	Ile, Pro, Val	−
Gly-Leu-Phe and Leu-Leu-Tyr	Human casein and bovine casein	Gly, Leu, Phe	−
His-Cys-Gln-Arg-Pro-Arg	Soybean Protein	Pro	Arg, His
Ala-Glu-Ile-Asn-Met-Pro-Asp-Tyr, Ile-Gln-Gln-Gly-Asn and Ser-Gly-Phe-Ala-Pro	Soybean Protein	Ile, Pro, Ala, Gly, Phe	−
Met-Ile-Thr-Leu-Ala-Ile-Pro-Val-Asn-Lys-Pro-Gly-Arg	Soybean Protein	Ile, Pro, Leu, Ala, Val, Gly	Lys, Arg Lys
Pro-Thr-Gly-Ala-Asp-Tyr	Alaska Pollock Protein	Pro, Gly, Ala	Pro
Asn-Gly-Met-Thr-Tyr, Asn-Gly-Leu-Ala-Pro and Trp-Thr	Alaska pollock frame Protein	Pro, Gly, Leu, Ala	−
Gln-Cys-Gln-Gln-Ala-Val-Gln-Ser-Ala-Val	Short-necked clam (Ruditapes philippinarum) Protein	Ala, Val	−
Gly-Val-Ser-Leu-Leu-Gln-Gln-Phe-Phe-Leu	Shellfish (M. coruscus) Protein	Gly, Val, Leu	−
Leu-Asp-Ala-Val-Asn-Arg and Met-Met-Leu-Asp-Phe	Edible microalgae Spirulina maxima Protein	Leu, Ala, Val	Lys, Arg
Pro-His-Thr-Cys, Val-Gly-Try-Thr, Glu-Phe, Leu-Phe, Glu-Gly-Ala-Lys, Trp-Ile and Trp-Leu	Paphia undulata meat Protein	Pro, Val, Gly, Leu, Ala	His, Lys
Pro-Ala-Tyr	Salmon pectoral fin by-Product Protein	Pro, Ala	−
Ala-Arg /Pro-Met/Val-Arg	Pinctada martensi	Pro, Ala, Val	Arg
Gly-Gly-Ser-Thr and Gly-Gly-Thr-Ser	Bovine placenta	Gly	−