RESUMO
Wound healing agents support the natural healing process, reduce trauma and likelihood of secondary infections and hasten wound closure. The wound healing activities of water in oil cream of the methanol extract of Hibiscus sabdariffa L. (Malvaceae) was evaluated in rats with superficial skin excision wounds. Antibacterial activities against Pseudomonas aeroginosa, Staphylococcus aureus and Echerichia coli were determined. The total flavonoid content, antioxidant properties and thin layer chromatographic fingerprints of the extract were also evaluated. The extract demonstrated antioxidant properties with a total flavonoid content of 12.30±0.09 mg/g. Six reproducible spots were obtained using methanol:water (95:5) as the mobile phase. The extract showed no antimicrobial activity on the selected microorganisms, which are known to infect and retard wound healing. Creams containing H. sabdariffa extract showed significant (P<0.05) and concentration dependent wound healing activities. There was also evidence of synergism with creams containing a combination of gentamicin and H. sabdariffa extract. This study, thus, provides evidence of the wound healing potentials of the formulated extract of the calyces of H. sabdariffa and synergism when co-formulated with gentamicin.
RESUMO
Tigernut starch has been isolated and modified by forced retrogradation of the acidic gel by freezing and thawing processes. Relevant physicochemical and functional properties of the new excipient (tigernut starch modified by acid gelation and accelerated (forced) retrogradation (ST(AM))) were evaluated as a direct compression excipient in relation to the native tigernut starch (ST(NA)), intermediate product (tigernut starch modified by acid gelation (ST(A))), and microcrystalline cellulose (MCC). The particle morphology, swelling capacity, moisture sorption, differential scanning calorimeter (DSC) thermographs and X-ray powder diffraction (XRD) patterns, flow, dilution capacity, and tablet disintegration efficiency were evaluated. The particles of ST(NA) were either round or oval in shape, ST(A) were smooth with thick round edges and hollowed center while ST(AM) were long, smooth, and irregularly shaped typically resembling MCC. The DSC thermographs of ST(NA) and MCC showed two endothermic transitions as compared with ST(A) and ST(AM) which showed an endothermic and an exothermic. The moisture uptake, swelling, flow, and dilution capacity of ST(AM) were higher than those of MCC, ST(A), and ST(NA). The XRD pattern and moisture sorption profile of ST(AM) showed similarities and differences with ST(NA), ST(A), and MCC that relate the modification. Acetylsalicylic acid (ASA) tablets containing ST(AM) disintegrated at 3±0.5 min as compared with the tablets containing ST(NA), ST(A), and MCC which disintegrated at 8.5±0.5, 10±0.5, and 58±0.8 min, respectively. The study shows the physicochemical properties of tigernut starch modified by forced retrogradation as well as its potential as an efficient direct compression excipient with enhanced flow and disintegration abilities for tablets production.
