Chia seed mucilage free oligosaccharides: Evaluation of Lactiplantibacillus plantarum WCFS1 α-galactosidase (LpαG) activities and prebiotic effect

Chia seed mucilage was probed for the presence of structurally diverse free oligosaccharides along with the assessment of hydrolytic and transgalactosylation ac­
tivities of α-galactosidase from a probiotic bacterium- Lactiplantibacillus plantarum WCFS1 (LpαG) on isolated oligosaccharides. Porous graphitic carbon-liquid
chromatography-tandem mass spectrometry (PGC LC-MS/MS) analysis revealed the presence of mainly sucrose (disaccharide), planteose (trisaccharide), few
isomeric tetrasaccharides as well as lower abundance of isomeric tri-, tetra-, penta- and hexasaccharides. In vitro evaluation of the digestibility of planteose and
tetrasaccharides to the intestinal enzymes did not generate monosaccharides. However, LpαG displayed hydrolytic activity towards planteose and selectively acted on
two tetrasaccharides, which were identified as sesamose and stachyose. In addition, transglycosylation property of LpαG using planteose led to the synthesis of
sesamose. Thus, the hydrolysis of planteose and sesamose was demonstrated for the first time for an α-galactosidase from the probiotic bacterium. Furthermore, the
oligosaccharides pool was shown to influence the growth of probiotic L. acidophilus, L. brevis and L. plantarum in vitro, along with the production of short chain fatty
acids (SCFAs). These findings would contribute to the potential application of chia seeds to further enhance its health benefits.