The relationship between charge intensity and bioactivities/processing characteristics of exopolysaccharides from lactic acid bacteria

Abstract The application of plant-based protein gels induced by lactic acid bacteria (LAB) fermentation is closely related to bioactivities and processing characteristics of exopolysaccharide (EPS). EPS produced by L. acidophilus (AEPS), L. casei (CEPS), L. mesenteroides (MEPS), and L. lactis (LEPS) were studied. CEPS showed the highest inhibition rates against α-amylase (55.47 ± 1.59%), α-glucosidase (60.47 ± 0.89%), HT-29 (70.68 ± 1.60%) and Caco-2 (60.80 ± 1.58%), but LEPS possessed the highest water solubility index (20.78 ± 1.92%) and water holding capacity (300.67 ± 10.19%). Thermal analysis revealed that EPS had melting points from 237.04 to 241.72 °C. The flow behavior and temperature-dependent behavior were fitted well with the Power Law model and Arrhenius model, respectively (R2 > 0.98). CEPS had more negative charge than other EPS, supported by zeta potential. Charge intensity was one of the mechanisms to regulate the EPS's bioactivities, and zeta potential could be used to evaluate its bioactivities.