Scalable purification and characterization of the anticancer lunasin peptide from soybean

PLoS One. 2012;7(4):e35409. doi: 10.1371/journal.pone.0035409. Epub 2012 Apr 13.

Abstract

Lunasin is a peptide derived from the soybean 2S albumin seed protein that has both anticancer and anti-inflammatory activities. Large-scale animal studies and human clinical trials to determine the efficacy of lunasin in vivo have been hampered by the cost of synthetic lunasin and the lack of a method for obtaining gram quantities of highly purified lunasin from plant sources. The goal of this study was to develop a large-scale method to generate highly purified lunasin from defatted soy flour. A scalable method was developed that utilizes the sequential application of anion-exchange chromatography, ultrafiltration, and reversed-phase chromatography. This method generates lunasin preparations of >99% purity with a yield of 442 mg/kg defatted soy flour. Mass spectrometry of the purified lunasin revealed that the peptide is 44 amino acids in length and represents the original published sequence of lunasin with an additional C-terminal asparagine residue. Histone-binding assays demonstrated that the biological activity of the purified lunasin was similar to that of synthetic lunasin. This study provides a robust method for purifying commercial-scale quantities of biologically-active lunasin and clearly identifies the predominant form of lunasin in soy flour. This method will greatly facilitate the development of lunasin as a potential nutraceutical or therapeutic anticancer agent.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Antineoplastic Agents
  • Chromatography, Ion Exchange
  • Electrophoresis, Polyacrylamide Gel
  • Enzyme-Linked Immunosorbent Assay
  • Histones / metabolism
  • Humans
  • Peptides / isolation & purification*
  • Peptides / metabolism*
  • Protein Binding
  • Soybean Proteins / isolation & purification*
  • Soybean Proteins / metabolism*
  • Soybeans / chemistry*
  • Spectrometry, Mass, Electrospray Ionization
  • Tandem Mass Spectrometry

Substances

  • Antineoplastic Agents
  • GM2S-1 protein, Glycine max
  • Histones
  • Peptides
  • Soybean Proteins