Maltotriosyl-erythritol, a transglycosylation product of erythritol by Thermus sp. amylomaltase and its application to prebiotic.

In this study, maltotriosyl-erythritol (EG) was synthesized as a novel prebiotic candidate via transglycosylation using recombinant amylomaltase (AMase) from Thermus sp. Tapioca starch served as the glucosyl donor, and erythritol as the acceptor. High-performance liquid chromatography (HPLC) revealed an EG yield of 14.0 % with a concentration of 2.8 mg/mL. Mass spectrometry confirmed the molecular weight of EG as 608 Da, and its strucopture was verified by H and C NMR analysis. EG exhibited greater resistance to acid, heat, and digestive enzymes compared to erythritol glucosides (EG) and significantly promoted the growth of Lactobacillus casei BCC36987. Fermentation of EG resulted in the highest levels of lactic acid and total short-chain fatty acids, which may contribute to reduced pH levels. These findings suggest that erythritol-receptor products formed via AMase-catalyzed reactions, particularly EG, are promising prebiotic ingredients, with the prebiotic activity of erythritol derivatives being influenced by the length of the carbohydrate chain.