Bioactive polysaccharides isolated from baobab fruit pulp: Enhancing antioxidant activity and reducing protein oxidation in goat myosin

This study isolated polysaccharides from Adansonia digitata (baobab) fruit pulp (BBP) using a hot-water extraction method. The BBP was deproteinized with Sevage reagent and decolorized using macro-porous resin (AB-8). The BBP was then precipitated by adding ethanol 95 %, producing BBP-1 and BBP-2 fractions. These were separated by DEAE-52 column chromatography with NaCl solutions 0 mol/L to 0.5 mol/L, yielding two neutral polysaccharides, BBP1-F1 and BBP2-F1, with respective yields of (18.10 ± 0.40 % w/w) and (16.40 ± 0.30 % w/w). Their carbohydrate contents were (75.30 ± 1.15 % w/w) and (81.10 ± 2.10 % w/w). Glucose was identified as the predominant monosaccharide, with concentrations of (78.90 ± 1.03 %) and (91.00 ± 1.09 %) for BBP1-F1 and BBP2-F1, respectively. The molecular weights of BBP1-F1 and BBP2-F1 were 21.2 kDa and 13.5 kDa, respectively. Both polysaccharides exhibited significant antioxidant properties. At a concentration of 0.1 mg/mL, BBP1-F1 and BBP2-F1 demonstrated DPPH free radical scavenging activities of (40.85 ± 2.82 %) and (37.66 ± 2.32 %), respectively, compared to myosin (13.20 ± 3.62 %). In addition, their iron ion reduction capacities were (28.00 ± 1.21 %) and (33.93 ± 2.00 %), respectively, compared to myosin (12.63 ± 0.55 %). These polysaccharides also inhibited myosin oxidation by preserving sulfhydryl groups, reducing carbonyl content, and increasing surface hydrophobicity. The results suggest that baobab polysaccharides enhance antioxidant activity and stability in meat proteins, which could be applied in food preservation and health-related applications to improve product quality and shelf life.