Structural characteristics, digestion properties, fermentation properties, and biological activities of butyrylated starch: A review

Butyrylated starch is produced by the esterification of hydroxyl groups in starch with butyryl groups, which improves the structural diversity of starch and expands its function and biological activity. The paper summarizes the structural properties and digestive properties, fermentation properties, and biological activities of butyrylated starch and describes the conformational relationships generated by the butyryl groups to reveal the underlying mechanisms. The butyryl groups replace the hydroxyl groups in starch and break the hydrogen bonds, which consequently changes the molecular, crystal, and granular structures of starch, while the starch structure also affects the distribution of the butyryl groups. Binding to the butyryl groups gives starch efficacy in resisting digestion, lowering the glycaemic index, releasing butyric acid in the colon, and regulating intestinal flora and metabolites. Relationships between starch structural parameters and butyric acid production and intestinal flora were also concluded to provide guidance for the rational design of butyrylated starch to improve efficacy. Moreover, based on its digestive and fermentation properties, butyrylated starch has exhibited good therapeutic efficacy for intestinal diseases, diabetes, polycystic ovary syndrome, and chronic restraint stress-induced abnormalities. This review provides a valuable reference for butyrylated starch advancement and utilization.

Study on the effect of different concentrations of choline glycine ionic liquid-water mixtures on debranched starch butyrylation reaction

In this study, the effect of choline glycine ionic liquids on the butyrylation of starch was investigated by the butyrylation of debranched cornstarch in different concentrations of choline glycine ionic liquid-water mixtures (choline glycine ionic liquids to water in mass ratios of 0:10, 4:6, 5:5, 6:4, 7:3, 8:2 and 10:0). The butyryl characteristic peaks in ¹H NMR and FTIR of the butyrylated samples indicated the success of butyrylation modification. ¹H NMR calculations showed that the most effective mass ratio of choline glycine ionic liquids to water (6:4) increased the butyryl substitution degree from 0.13 to 0.42. X-ray diffraction results showed that the crystalline type of the starch modified in the choline glycine ionic liquid-water mixtures changed from B-type to a mixture of V-type and B-type isomers. The butyrylated starch modified in the ionic liquid increased its own content of resistant starch from 25.42 % to 46.09 %. This study highlights the effect of different concentrations of choline glycine ionic liquid-water mixtures on the promotion of starch butyrylation reactions.