The Formation of an Anti-Cancer Complex Under Simulated Gastric Conditions

Abstract

A potent anti-cancer complex has previously been formed from two major components of milk. Human/bovine α-lactalbumin made lethal to tumour cells (H/BAMLET) is a protein–fatty acid complex that has been produced using the whey protein α-lactalbumin (α-LA) and the fatty acid oleic acid (OA). It was shown that it possesses selective anti-tumour and anti-microbial activity, which was first identified in acidic fractions of human breast milk. The aim of this study was to determine whether the two components would form a bioactive complex during simulated gastric (GI) transit. Results showed that a complex consisting of α-LA and OA is formed as the protein unfolds under acidic conditions and subsequently refolds upon pH increase. Analysis of this complex using Nuclear Magnetic Resonance and Fourier Transform Infra-Red (FTIR) spectroscopies estimated a stoichiometry of 4.1 and 4.4 oleic acids per mole of protein, respectively. FTIR and fluorescence spectroscopies showed that the structure was similar to that of BAMLET. Cytotoxicity testing against cancer cell line U937 cells showed that the complex had an LC50 value of 14.08 μM compared to 9.15 μM for BAMLET. These findings suggest that a BAMLET-like complex may be formed under the tested in vitro GI conditions.