Direct and Regioselective Di‐α‐fucosylation on the Secondary Rim of β‐Cyclodextrin

Abstract

Invited for the cover of this issue is the group of Marthe Walvoort at the University of Groningen. The image depicts a cyclodextrin ring as a dartboard, which is hit with fucose darts at specific positions to give a di‐fucosylated product. Read the full text of the article at 10.1002/chem.201806090.

Digestion, fermentation, and pathogen anti-adhesive properties of the hMO-mimic di-fucosyl-β-cyclodextrin

“…Using appropriately functionalized β-cyclodextrin and fucose building blocks, the di-fucosylated DFβCD was obtained in a highly regiospecific manner using chemical strategies. [28] Since the Fuc moieties are connected to the O-3 position of the backbone glucoses, the decorative pattern mimics the pattern in 3-FL (Figure 1), which also contains a Fuc moiety that is -1,3 linked to glucose. As a result of this straightforward approach, DFβCD was produced in sufficient quantities (~ 0.5 g) to test its functional activity, and to determine whether this structural hMO mimic also is a functional hMO mimic.…”

“…Difucosylated β-cyclodextrin (DFβCD) was chemically synthesized based on the commercially obtained β-cyclodextrin (βCD), as described previously, and monofucosylated βcyclodextrin (MFβCD) was isolated as a side product. [28] Pancreatin from porcine pancreas (containing amylase, lipase, and protease) and amyloglucosidase (260 U/mL) were obtained from Sigma-Aldrich (St. Louis, MO, USA). All materials needed for preparation of SIEM medium were obtained from Tritium Microbiology.…”

“…Therefore, we recently developed a chemical strategy to produce di-fucosylated β-cyclodextrin (DFβCD, Figure 1). [28] The family of cyclodextrins has the GRAS status (Generally Recognized As Safe), and they are frequently used in medical formulations and as food additives. [29] -Cyclodextrin (CD) is shown in Figure 1 and contains seven glucose (Glc) residues linked in an -1,4 fashion, analogous to the structural composition of maltooligosaccharides.…”

“…Both 2'-FL, 3-FL, and βCD are efficiently fermented by microbial enzymes, whereas DFβCD is resistant to bacterial fermentation. We hypothesize that the resistance observed for DFβCD is a result of the specific positioning of the two Fuc units on opposite sides of the βCD ring (specifically at the A and D position) [28]. This may block the accessibility to the microbial α-amylases sufficiently to resist fermentation, at least over the course of the 24 h incubation.Overall SCFA production in all fermentated substrates after 24 h did not differentiate much from the levels of SCFAs produced in the medium-only samples, presumably due to the low substrate concentration used (2 mg/mL) [36].…”