Pectin from Fructus Mori relieve oxidative stress and regulates gut microbiota in POF mice.

Pectin, a complex acidic heteropolysaccharide with diverse biological activities, is widely unilized in cosmetics and food industry. Fructus Mori (F. Mori), an important cultivated fruit, contains abundant pectin. In this study, a pectic polysaccharide (FPA1-1) was extracted from F. Mori through hot-water extraction, ethanol precipitation, and chromatographic purification. Structural analysis revealed that FPA1-1 was a rhamnogalacturonan-I (RG-I)-rich mixed pectin with a branching degree of 48.42 %. In vivo experiments, FPA1-1 (400 mg/kg) effectively shortened the oestrous cycle, reduced follicle stimulating hormone (FSH) level, promoted synthesis and secretion of estradiol hormone (E2) and luteinizing hormone (LH), suppressed serum interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels and improved antioxidant capacity in premature ovarian failure (POF) mice. Moreover, FPA1-1 modulated gut dysbiosis of POF mice by decreasing Firmicutes/ Bacteroidetes ratio and Desulfobacterota abundance at phylum level, enriching Bacteroides, Prevotellaceae, Parabacteroides, Alloprevotella, and Muribaculaceae abundance and inhibiting Desulfovibrionaceae proliferation. FPA1-1 treatment increased short-chain fatty acids (SCFAs) level. Antibiotic cocktail treatment and fecal microbiota transplantation (FMT) experiments confirmed that FPA1-1 ameliorates the ovarian function through altering the gut microbiota composition. These findings provided an experimental basis for further research and applications of F. mori pectin in female ovarian health.