Extraction, Purification, Characterization, and Wound Healing Effects of Novel Prickly Pear (Opuntiaficus-indica (L.) Mill.) Heteropolysaccharides.

Background: The present study undertakes the purification of a novel polysaccharide from Tunisian prickly pear (Opuntiaficus-indica (L.) Mill.) rackets (PPPRs) and the determination of its physicochemical properties, structure, antibacterial and antioxidant properties, as well as its in vitro and in vivo wound healing potential. Methods: The PPPR was structurally analyzed by Fourier Transform Infrared Spectroscopy (FTIR) and UV/Visible Spectroscopy, revealing characteristic bands of polysaccharides. According to thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), and Gas Chromatography-Mass Spectrometry (GC-MS) analyses. Results: The crude PPPR is an heteropolysaccharide composed of glucose (62.4%), galactose (19.37%), mannose (10.24%), and rhamnose (7.98%), with an average molecular weight of 90.94 kDa. This novel polysaccharide exhibited notable antioxidant potential assessed by four different in vitro assays: the 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging assay, ferric reducing power, ferrous chelating activity, and scavenging activity against 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS). In addition, the PPPR displayed high antibacterial activities with a MIC of 2.5 mg/mL against Salmonella Typhimurium and Pseudomonas aeruginosa, cytocompatibility properties, and non-cytotoxicity. Subsequently, the effect of the PPPR on skin wound healing was studied in a diabetic rat model induced by alloxan, revealing a significant acceleration in the wound healing process. This acceleration was evidenced by the expedited recovery of the dermis, increased formation of blood vessels, and enhanced tissue granulation. Conclusion: Therefore, the findings offer fresh perspectives on the creation of a potentially efficient and promising racket polysaccharide-based therapy for the treatment of persistent diabetic wounds.