Isolation, characterization and anti-UVB irradiation activity of an extracellular polysaccharide produced by Lacticaseibacillus rhamnosus VHPriobi O17

The purpose of this study was to isolate exopolysaccharides (EPS) from lactic acid bacteria (LAB) and evaluate EPS anti-UVB viability. Lacticaseibacillus rhamnosus VHPriobi O17 with high EPS production was screened from 34 strains of LAB. The EPS (OP-2) produced by L. rhamnosus VHPriobi O17 was purified by alcohol precipitation and DEAE-μSphere anion exchange chromatography. By ion chromatography, FT-IR spectrum and gel column chromatography, EPS (OP-2) was a novel Man-like polysaccharide with the weight-averaged molecular of 84.2 kDa. The EPS (OP-2) can effectively alleviate HaCaT cells apoptosis and overproduction of reactive oxygen species (ROS) induced by UVB. The results also showed that it inhibited the release of pro-inflammatory cytokines (IL-1α, IL-6 and IL-8); and suppressed the phosphorylation cascade of JNK and p38 MAPK to reduce the expression level of active-caspase3, ultimately prevented cell apoptosis. Thus, the EPS produced by L. rhamnosus VHPriobi O17 have the potential to be used for human anti-UVB irradiation.