Structural and inflammatory characteristics of Maillard reaction products from litchi thaumatin-like protein and fructose

Abstract

The structural characteristics and inflammatory activity of Maillard reaction products (MRPs) from fructose (Fru) and litchi thaumatin-like protein (LcTLP) with a pro-inflammatory activity were investigated. The structural changes of LcTLP-Fru MRPs were divided into two stages during the Maillard reaction. In 0-6 h, the unfolding and degradation of the LcTLP were dominant, resulting in a looser structure; the increase of β-sheets was 13.02%; the decrease of α-helices was 9.21%; and both the molecular weight and gyration radius R_g decreased. After 6 h, the enhanced glycosylation caused the molecular weight to increase, while R_g remained low, implying that the molecular structure became more compact. In addition, LcTLP-Fru MRPs reduced the inflammation response by significantly reducing the gene and protein expressions of tumor necrosis factor-α, interleukin-1β, and interleukin-6 compared with the LcTLP group in RAW264.7 macrophages. The findings provided a theoretical foundation for addressing the inflammatory response caused by litchi products consumption.

Keywords: Fructose; Inflammatory activity; Litchi thaumatin-like protein; Marillard reaction; Molecular structure.