Modified sunflower pectin with low molecular weight and methylation targets gut microbiota to alleviate obesity

Abstract Obesity has become a global public health crisis, and the development of safe and effective interventions are urgently needed. In this study, sunflower head pectins with different molecular weights and degrees of methylation were synthesized via enzymatic modification. A high-fat diet was used to induce obesity in a mouse model. The effects of different modified pectins on the regulation of lipid metabolism disorders were systematically evaluated, and 16S rRNA sequencing was used to elucidate the mechanism by which different modified pectins regulate gut microbiota homeostasis and affect body metabolism disorders. The results showed that low-molecular-weight and low-methoxyl pectin could significantly reduce the weight growth rate ( P < 0.05) and reverse hepatic steatosis. Its mechanism was closely related to the improvement of microbiota composition and recovery of short-chain fatty acid levels. This research has laid a theoretical foundation for precisely regulating the structure of pectin to develop pectin-enriched functional foods • The fat reduction effects of pectin molecules modified with different modifications show significant differences. • Methylation degree has a stronger effect on fat reduction by low molecular weight pectin. • Low-molecular-weight and low-methoxyl pectin (pectin-A) have the best fat reduction effect.