Aleksandra Karmańska, Bolesław Tomasz Karwowski
Lunazine – biologically active peptide from soybean
Food is a source of biologically active peptides, which have a positive effect on a number of human physiological functions. An important and studied compound from the group of peptides is lunazine isolated from soybeans. It is also found in wheat, barley and rye grains but in smaller amounts. It consists of 43 amino acid residues with a molecular weight of 5.5 kDa. Studies have shown that lunazine has antioxidant, anti-inflammatory and chemoprotective properties and can also have a beneficial effect on the lipid profile. Lunazine's chemoprotective properties have been confirmed on various cell models - such as NIH/3T3 mouse fibroblasts, leukemia cells, HT-29 human colorectal cancer and RWPE-2 prostate epithelium, HepG2 human liver and MCF-7 and MDA-MB-231 breast cancer. Three domains are responsible for the anticancer activity of lunazine: the RGD motif (arginine, glycine and aspartic acid), the spiral region (EK HI MEI QG), which is structurally homologous to the region found in chromatine-binding proteins and the end of polyaspartic acid. Caco-2 cell line studies have proven that lunazine neutralizes ROS produced by hydrogen peroxide and tert-butyl hydrogen peroxide. The composition and sequence of amino acids, especially glycine, leucine, phenylalanine, proline against lipid peroxidation, tryptophan and cysteine, have the strongest influence on the antioxidant activity of lunazine peptides. Lunazine has anti-inflammatory properties by inhibiting the production of pro-inflammatory mediators induced by LPS lipopolysaccharide, which can also contribute to chemoprotection.
This peptide is thermally stable and is not degraded in the gastrointestinal tract, which allows high bioavailability. Lunazine is protected from gastrointestinal enzymes (pepsin, pancreatin) thanks to the presence of Bowman-Birk protease inhibitors (BBI) and Kunitz trypsin inhibitors (KTI) in soy.
This review presents some of the potential health and therapeutic benefits of lunazine.
Keywords: polypeptide, cancer prevention, lunasin, bioavailability of lunasine.
© Farm Pol, 2020, 76(9): 493–499