Preliminary evaluation of potential prebiotic capacity of selected legumes and seed mucilage on the probiotic strain Lactobacillus rhamnosus GG

The characterization of the prebiotic potential of legumes and mucilage are essential and crucial for the development of symbiotic food products. The aim of the present study was to compare and to determine the prebiotic capacity of selected legumes, namely adzuki bean, mung bean, black cowpea, and mucilages from chia seed and flaxseed on the growth of Lactobacillus rhamnosus GG. Resistance towards acid, pancreatin hydrolysis, and the prebiotic scores of the tested substances was determined based on growth promotion after 24 h of incubation. Results revealed that flaxseed mucilage was more resistant against hydrolysis by acid (1.47%) and pancreatin (2.64%) compared to the other samples (5.64 – 18.06% for acid and 10.34 – 15.57% for pancreatin). The relative prebiotic scores for flaxseed mucilage and black cowpea were 98% and 94%, respectively, which were higher than commercial prebiotics including inulin, fructooligosaccharides, and isomaltooligosaccharides. The optimum concentrations of flaxseed mucilage and black cowpea during 36 h of fermentation were 0.8% and 0.4% (w/v), respectively. The findings indicated that flaxseed mucilage was partially digested during gastrointestinal transit and it promotes the growth of the L. rhamnosus GG. The potential prebiotic capacity of flaxseed mucilage and its symbiotic relationship with L. rhamnosus GG suggests that they can be incorporated together for the development of functional foods.