From oil to microparticulate by prilling technique: Production of polynucleate alginate beads loading Serenoa Repens oil as intestinal delivery systems

Natural oils that are rich in biologically active polyunsaturated fatty acids have many health benefits but have insufficient bioavailability and may oxidize in the gastrointestinal tract. For these reasons and to improve the handling as well, the possibility of incorporating a natural oil, extracted from Serenoa Repens fruits (SR-oil), in alginate-based beads was investigated. SR-oil has been used from centuries in both traditional and modern medicine for various nutraceutical or therapeutic purposes such as, in both sexes, as a general tonic, for genitourinary problems, to increase sexual vigor, as a diuretic or to treat in male lower urinary tract symptoms and benign prostatic hyperplasia. In this study, alginate-based beads prepared by vibration technology, also known as prilling technique, were explored as SR-oil delivery systems. Twenty-seven different formulations (F1-F27) were produced starting from stable emulsions for the period of the production. The formulations having spheroid shape (sfericity factor <0.07), high formulation yield (>90%) and high encapsulation efficiency (EE% > 80) were selected for further characterizations. Gas chromatographic analysis revealed a high loading of lauric acid as principal component of SR-oil allowing to calculate the content of total fatty acids (>50%) into the beads. Swelling behavior and release features were also studied at different pH values. The swelling of the beads and their SR-oil release were negligible for the first 2 h in simulated gastric fluid (pH 1.2), and appreciable in simulated intestinal fluid (pH 6.8). The release data were fitted by various equations to define the release kinetic mechanism. In addition, the selected formulation (F16) was stable to the oxidation not only during the formulation process, but also after 3 months of storage at room temperature. In summary, these polynucleate alginate beads, produced by prilling technique, are promising systems for improving the intestinal specific delivery and bioavailability of health-promoting bioactive SR-oil.