Interaction characterization of 5−hydroxymethyl−2−furaldehyde with human serum albumin: Binding characteristics, conformational change and mechanism

5−Hydroxymethyl−2−furaldehyde (5-HMF) is a kind of by-product produced in food processing, which may cause latent hazard to human health. Here, the interaction of 5-HMF with human serum albumin (HSA) was studied by multi-spectroscopic methods, multivariate curve resolution-alternating least squares (MCR−ALS) and molecular docking . The formation of 5-HMF−HSA complex was confirmed by MCR−ALS. The fluorescence quenching mechanism of HSA by 5-HMF was static , and their binding constant was 5.25 × 10 4  L mol −1  at 298 K, the binding site of 5-HMF was located in subdomain IIA of HSA. The main forces of the interaction were hydrogen bonds and van der Waals forces . The molecular docking showed that three hydrogen bonds were formed between –CH 2 OH of 5-HMF and Lys106, Pro147 and Gln29 of HSA. The synchronous fluorescence, three-dimensional fluorescence and circular dichroism spectra showed that 5-HMF induced a structural shrinkage of HSA. Fluorescence phase diagram ascertained that the HSA conformational change was in accordance with all-or-none model. Moreover, the presence of the food nutrients (vitamin C, chlorogenic acid and phloretin) weakened the binding of 5-HMF with HSA. This study is helpful to understand the hazard mechanism of 5-HMF to human body and provides new strategies to reduce the hazard of 5-HMF.