Influence of monosaccharides and lipids on protein structure and solubility-Reaction simulation of sludge thermal hydrolysis system.

During the hydrothermal treatment process, sludge proteins can interact with other organic matter, thereby affecting protein structure and altering protein solubility. This paper investigates the effects and causes of monosaccharides and lipids on protein structure and solubility during thermal hydrolysis of sludge. The results indicated that monosaccharides increase protein solubility by preventing the conversion of proteins into free amino acids. Monosaccharides can reduce the temperature sensitivity of benzene, pyridine and other heteroaromatic rings, thereby reducing the generation of conjugated structures during thermal hydrolysis of sludge. The temperature and activation energy of proteins denaturation increased with increasing glucose concentration. Heating promotes the disappearance of the protein's α-helix structure, while glucose tends to aggregate on the protein surface and form hydrogen bonds, thereby inhibiting further protein denaturation and precipitation. This study provides insight into the effect of organics on protein solubility during thermal treatment of sludge.