Encapsulación de la piperine presente en la especie Piper tuberculatum utilizando vesículas multilamelares y determinación de su poder antioxidante

Abstract

The piperine is an alkaloid present in the vegetal species pipilongo (Piper tuberculatum). Antioxidant properties are associated to this plant. It was encapsulated in multilamellar vesicles (MLV). For that, the validation of the extraction methodology through calibration curves of standard piperine by high resolution liquid chromatography (HPLC) was performed, using a column of C18, mobile phase MetOH: H2O (70:30) and detected by UV to 340nm with a fluency rate of 0.7 mL/ min. The lineal and non-lineal ranges were found between 1 and 300 ppm, with R2 of 0.995. During the extraction of the pipilongo fruit, the effect of two factors, solvents and ultrasound power, was studied, for the optimization of conditions and higher extraction of piperine in pipilongo. The maximum concentration of piperine (246.50 ppm) was found, using ethanol as extraction solvent. The piperine was isolated from its extract, using a solution of KOH with 10 % ethanol. It was purified and characterized by melting point, IR, GC-MS y RMN 1H. Once the extract was obtained, it was proceeded to the formation of liposomes. The phosphatidylcholine and cholesterol vesicles were prepared with extract and with piperine at different concentrations and hydrated with buffer pH 7.40. The average size of the particles formed, measured by dynamic light scattering (DLS), was in a range of 299.7–531.9 nm. For the study of antioxidant activity, a solution of DPPH 0.2 mM was prepared and a reaction was carried out with the extract and piperine liposomes and their corresponding free forms. The IC50 calculated for the extract and piperine were 2.8±0.2 and 21333±1499 ppm, respectively. These values of IC50 were compared against a standard of reference Quercetin, prepared under the same conditions. The test with DPPH showed that the released form possesses greater antioxidant activity while in encapsulation form, it attenuates and stabilizes this capacity.