Potential of Pectins to Beneficially Modulate the Gut Microbiota Depends on Their Structural Properties

Abstract

Pectins are plant cell-wall polysaccharides which can be utilized by commensal bacteria in the gut, exhibiting beneficial properties for the host. Knowledge of the impact of pectins on intestinal bacterial communities is insufficient and limited to a few types of pectins. This study characterized the relationship between the structural properties of pectins and their potential to modulate composition and activity of the gut microbiota in a beneficial way. For this purpose we performed in vitro fermentations of nine structurally diverse pectins from citrus fruits and sugar beet, and a pectic derivative, rhamnogalacturonan I (RGI), using a TIM-2 colon model. The composition of microbiota during TIM-2 fermentations was assessed by 16S rRNA gene amplicon sequencing. Both general and pectin-specific changes were observed in relative abundances of numerous bacterial taxa in a time-dependent way. Bacterial populations associated with human health, such as Faecalibacterium prausnitzii , Coprococcus , Ruminococcus , Dorea , Blautia , Oscillospira , Sutterella , Bifidobacterium , Christensenellaceae , Prevotella copri , and Bacteroides spp. were either increased or decreased depending on the substrate, suggesting that these bacteria can be controlled using structurally different pectins. The main structural features linked to the pectin-mediated shifts in microbiota included degree of esterification, composition of neutral sugars, distribution of homogalacturonan and rhamnogalacturonan fractions, degree of branching, and the presence of amide groups. Cumulative production of the total short chain fatty acids and propionate was largest in fermentations of the high methoxyl pectins. Thus, this study indicates that microbial communities in the gut can be specifically modulated by pectins and identifies the features in pectin molecules linked to microbial alterations. This knowledge can be used to define preferred dietary pectins, targeting beneficial bacteria, and favoring more balanced microbiota communities in the gut.

Use of Changestat for Growth Rate Studies of Gut Microbiota

“…The ratio of acetate, propionate and butyrate was 5:2:1 at D low and 14:2:1 at D high . Similar to the product profile at D low , a ratio of 4:2:1 for acetate:propionate:butyrate was reported by Larsen et al (2019) in TIM-2 experiments. In accordance with the organic acid profiles, about twice as much carbon dioxide was produced at D low than at D high (20.3 ± 2.4 and 10.5 ± 2.8 mmol per L medium, respectively).…”

“…Accordingly, in vivo studies have shown that Akkermansia and ruminococci are more prevalent in people with slow colonic transit, while Bifidobacterium and Lachnospiraceae correlate with high transit rates (Kim et al, 2015;Roager et al, 2016;Vandeputte et al, 2016). The impact of pectin structure on the dynamics metabolism and fecal microbiota has been shown by Larsen et al (2019). Highly methoxylated pectins were shown to stimulate F. prausnitzii, commonly referred to as a health-promoting species.…”

Oral therapy with colonization factor antigen I prevents development of type 1 diabetes in Non-obese Diabetic mice

“…Linear discriminant analysis (LDA) revealed differential abundance of many bacterial taxa among the groups (Fig. 4C-E), most notably an enrichment of Lactobacilli and Ruminococcus, which have been described as beneficial to human health 38,39 , in mice treated with LL-CFA/I compared to those given LL vector (Fig. 4E).…”

The effects of different dietary fiber pectin structures on the gastrointestinal immune barrier: impact via gut microbiota and direct effects on immune cells

“…These effects may be exerted by direct interactions with the gastrointestinal immune barrier, as some types of pectins are known to interact with immune receptors 29,30 . Furthermore, pectins may protect the intestinal barrier indirectly by stimulating the growth and diversity of microbiota communities as pectins are known to stimulate microbial communities 31 . These effects are strongly dependent on the chemical structure of pectins [29][30][31] .…”

“…Furthermore, pectins may protect the intestinal barrier indirectly by stimulating the growth and diversity of microbiota communities as pectins are known to stimulate microbial communities 31 . These effects are strongly dependent on the chemical structure of pectins [29][30][31] . In recent years, many studies have demonstrated the impact of specific structural features of pectins on their health benefits to consumers 32 .…”