OBTAINMENT OF NANOEMULSION CONTAINING THE EXTRACT OF THE PLANT SPECIES Jatropha gossypiifolia AND EVALUATION OF in vivo WOUND HEALING ACTIVITY
Wounds. Medicinal plants. Euphorbiaceae. Antioxidant Potential
Wound healing is essential for restoring physiological conditions and avoiding complications. In this process there is the release of free radicals, which, in excess, will lead to complications, along with exacerbated inflammation. Thus, several drugs can be used to accelerate healing, with specific actions. However, medicinal plants, because they have a diversity of compounds in their composition, can act in different ways, among these plants is the species Jatropha gossypiifolia (Jg), already popularly used to treat wounds and inflammations. Therefore, this study objective to develop a topical nanoemulsion containing the hydroethanolic extract of Jg leaves, to evaluate the healing activity, contributing to the development of alternatives for the treatment of cutaneous wounds. The phytochemical characterization of the Jg extract was performed using High Performance Liquid Chromatography coupled to a photodiode array detector (HPLC-DAD) and quantification of the phenolic and flavonoid. HPLC- DAD identified the presence of flavonoids, with detection of vitexin and derivatives of luteolin and apigenin, and the quantification of phenolics and flavonoids detected 95.08 ± 5.46 mg of gallic acid/g of extract and 137.92 ± 0 .99 mg of quercetin/g of extract, respectively. Then, a nanoemulsion was developed to convey the Jg extract (NJg), in order to improve physical stability and permeability. The physical-chemical characterization of the nanoemulsion was carried out by checking the average droplet size, polydispersive index (PDI), pH and quantification of phenolics, in addition to macroscopic analysis. The same parameters were used for the stability study. The NJg (n=2) had an average size of 164.96 ± 9.487, PDI of 0.217 ± 0.026, pH of 5.89 ± 0.0281 and phenolic content of 32.039 ± 14.628 mg of gallic acid/g of extract, not showing color variation or phase separation. Over the course of 4 weeks, the characteristics were maintained. In order to evaluate the in vitro cytotoxicity, the hemolytic and crystal violet assays were performed, in which the extract and the nanoemulsion did not show toxicity at the tested concentrations (32.25-250 µg/mL). Also, the antioxidant activity of the extract and nanoemulsion was performed throught of the reducing ABTS and DPPH radicals, with the two samples capable of reducing radicals tested with IC50 of 0.2999 and 0.4646 µg/µL for the ABTS∙+ radical, respectively, and 0.2899 and 0.4374 µg/µL for the DPPH radical, respectively. Finally, the healing activity was evaluated, in which NJg presented significant wound closure from the 5th day of treatment, when compared to the untreated group, 45% for NJg and 21% for the untreated group, and on the 8th day reaching 58%. In addition, NJg promoted the reduction of nitrite, myeloperoxidase activity and cytokines. Thus, the results suggest that the developed nanoemulsion containing J. gossypiifolia extract is promising and may be contributing to the treatment of wounds.