Biofunctionalization of selenium nanoparticles using a Sonneratia caseolaris (L.) leaves polysaccharide: Statistical...

A central composite design (CCD) was employed to optimize the synthesis of selenium nanoparticles (SeNPs) using a Sonneratia caseolaris mangrove polysaccharide (SCLP) as a stabilizer to the redox system of sodium selenite and ascorbic acid (Vc). The size, morphology, and physicochemical properties results showed that the orange-red, monodisperse spherical SCLP-SeNPs with an average diameter of approximately 81.31 ± 0.58 nm were successfully prepared under the optimal synthesis conditions. The stability analysis revealed that OH and CO groups of SCLP bound with SeNPs provided excellent storage stability for more than 2 months at 4 °C in an aqueous solution. The XRD, Raman spectra, and thermal property results of SCLP-SeNPs demonstrate a Zero-valent crystalline trigonal phase of Se with a maximum degradation temperature of 450 °C. SCLP-SeNPs showed significantly enhanced in vitro antimicrobial and antibiofilm effects against Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, and Aeromonas hydrophila. Additionally, SCLP-SeNPs showed synergistically superior scavenging activity against DPPH, ABTS, hydroxy, and superoxide anion radicals compared to bare SeNPs. The toxicity assay suggested that SCLP-SeNPs exhibited reduced toxic effects on both in vitro and in vivo, indicating their excellent biocompatibility and prospective utilization as an antioxidant and antibiofilm agent in food applications.