Window on Bacillus maritimus MSM1 Exopolysaccharide Characterization and Possibility of its Anti-Alzheimer Property in In-Vitro Model

Four bacterial isolates were obtained from marine sediments, collected from Sahl Hashish, Hurghada Red Sea, Egypt. The four isolates were screened for exopolysaccharides (EPS) production and acetylcholinesterase inhibition. The most promising isolate S16 provided the highest EPS yield (7.51 g/L) and acetylcholinesterase inhibition was identified morphologically and genetically using 16S rRNA gene sequence analysis as Bacillus maritimus . Physico-chemical analysis of BMEPS using UV-Vis was estimated uronic acid and sulfate contents to be 24.7% and 18.3%, respectively. HPLC analysis indicated that it Mannuronic acid, glucouronic acid, glucose, and mannose are present in a molar ratio of 0.8:1.0:2.8:2.3, respectively. Further, FT-IR showed the abundance of β-configurations. The GPC estimated the average molecular weight (Mw) to be 4.31´10 4 g/mol. BMEPS successfully inhibited AChE (IC 50 ; 691.77± 8.65μg/ ml), BuChE (IC 50 ; 288.27±10.50μg/ ml), and tyrosinase (IC 50 ; 3.34±0.09, 14.00± 0.14, and 22.96 ± 1.23μg/ ml during incubation durations of 10, 20, and 40 minutes); It also demonstrated a selective anti-inflammatory action against COX-2 rather than COX-1. Furthermore, BMEPS showed powerful antioxidant capabilities such as free radical and oxygen reactive species (ROS) scavenging, metal chelation, reduction capacity, and suppression of lipid peroxidation. These activities are due to its distinct chemical composition, which includes sulfated moieties (18.30%) and uronic acids (24.70%). The findings of this study indicate that BMEPs shown promising anti-disease Alzheimer's activity in vitro, qualifying them for inclusion in advanced preclinical studies for the discovery of alternative treatment.