Hawthorn pectin mitigates high-fat diet induced hyperlipidemia in mice through promoting Dubosiella newyorkensis

Hawthorn fruit is rich in pectins; however, the gut microbiota-modulating effects of hawthorn pectin remain unclear. In this study, enzyme-extracted hawthorn pectin ( M w : 126.24 kDa; HG/RG-I ratio: 55.64 %/37.93 %; branching degree: 2.44) was fractionated into two components: D1 (spherical, 345.76 kDa, HG/RG-I 57.48 %/37.25 %, branching degree 2.16) and D2 (flexible, 17.20 kDa, HG/RG-I 78.24 %/21.76 %, branching degree 1.33). Hawthorn pectin directly stimulated Dubosiella newyorkensis and Bifidobacterium bifidum growth in vitro . In hyperlipidemic mice, it alleviated dyslipidemia and enriched Lactobacillus and Dubosiella . Parallel experiments confirmed that D. newyorkensis supplementation similarly reduced dyslipidemia and enhanced Lactobacillus abundance, mediated by bacterial acetate production. Only D1 mimicked the pectin's prebiotic activity, promoting D. newyorkensis and B. bifidum growth. The high-RG-I D1, with elevated branching and larger M w , was identified as the key driver of hawthorn pectin's prebiotic effect. These findings highlight that hawthorn pectin and D1 specifically target probiotic D. newyorkensis to synergize with Lactobacillus against hyperlipidemia.