Structural characterisation of two polysaccharides from white common bean (Phaseolus vulgaris L.) and the application in microencapsulation of probiotics

Summary Increasing attention has been focused on the application of plant polysaccharides in the area of microencapsulation of probiotic bacteria. It remained to be clarified how the chemical structure of plant polysaccharides affects their feasibility as wall materials. In this study, two structurally different polysaccharides, namely NSP‐1 (2.91 × 10 6 Da) and NSP‐2 (4.57 × 10 5 Da), were isolated from white common bean seeds. NSP‐1 was predominantly composed of Glc and Gal, and mainly linked as →4)‐Glc p ‐(1→, →3,6)‐Glc p ‐(1→ and →4)‐Gal p ‐(1→. NSP‐2 was predominantly composed of Gal and Ara, with main glycosidic bonds of →4)‐Gal p ‐(1→, Gal p ‐(1→ and →5)‐Ara f ‐(1→. NSP‐1 and NSP‐2 were co‐used with calcium alginate as wall materials for microencapsulation of Lactobacillus plantarum . NSP‐1 increased the encapsulation efficiency more than NSP‐2 ( P < 0.05), while NSP‐2 mainly improved the survival of the probiotic during simulated gastrointestinal tract digestion and storage at 4 °C ( P < 0.05). These findings will give a valuable perspective on plant polysaccharides applied in microencapsulation technology.