Structural elucidation of a polysaccharide from Lonicera japonica flowers, and its neuroprotective effect on cerebral ischemia-reperfusion injury in rat

•LJPB2 was a neutral hetero-polysaccharide isolated from Lonicera japonica flowers.•LJPB2 exhibited a strong DPPH scavenging activity.•LJPB2 improved the neurological deficit scores and infract volume.•LJPB2 remarkably reduced the MDA level and NO production.•LJPB2 elevated the SOD and GSH-Px enzyme activities.