Effects of enzymatic hydrolysis on the structural, rheological, and functional properties of mulberry leaf polysaccharide

Effects of enzymatic hydrolysis on the structural, rheological, and functional properties of mulberry leaf polysaccharide (MLP) were characterized in this study. The enzymatic hydrolysis of MLP raised the carbonyl, carboxyl, and hydroxyl groups from 7.21 +/- 0.86 to 10.08 +/- 0.28 CO/100 Glu, 9.40 +/- 0.13 to 17.55 +/- 0.34 COOH/100 Glu, and 5.71 +/- 0.33 to 8.14 +/- 0.24 OH/100 Glu, respectively. Meanwhile, an increase in thixotropic performance and structure-recovery capacities were observed in hydrolyzed MLP, while the molecular weight, surface tension, apparent viscosity, and thermal stability were decreased. An improved antioxidant activity of MLP was also achieved after the enzymatic degradation. Moreover, the hydrolyzed MLP showed greater ability to promote the growths of Bifidobacterium bifidum, Bifidobacterium adolescentis, Lactobacillus rhamnosus, and Lactobacillus acidophilus and the production of acetic acid, butyric acid, and lactic acid. The results demonstrate that enzymatic modification is a useful approach for polysaccharide processing.

Automated summary

The enzymatic hydrolysis of mulberry leaf polysaccharide (MLP) resulted in an increase in carbonyl, carboxyl, and hydroxyl groups, as well as improved thixotropic performance, antioxidant activity, and promotion of beneficial bacteria growth and acid production. However, it also led to a decrease in molecular weight and thermal stability.