Extracción, microencapsulación y evaluación de la capacidad antioxidante de las antocianinas presentes en las flores de Hibiscus sabdariffa cultivadas en el cantón Milagro, provincia del Guayas

Abstract

Anthocyanins are water-soluble pigments used as colorants in the preparation of beverages, wines, and infusions. Due to their antioxidant properties, they are considered as chemoprotective agents and are used in disease treatment. The present research work consisted of the extraction, microencapsulation, and evaluation of the antioxidant capacity of anthocyanins present in Hibiscus sabdariffa or Jamaica Flower, a plant cultivated in Milagro city, in the coastal region of Ecuador. This plant is highly recognized for its medicinal properties since it contains multiple vitamins, minerals, and bioactive compounds important for health. For its extraction, a ratio of 1:25 plant material to volume of solvent was used, at a constant temperature of 85 degrees Celsius for 30 minutes. The extracted bioactive substance was concentrated and microencapsulated by means of the spray drying technique using a polymeric matrix (maltodextrin) where its microencapsulation efficiency was 88.02 percent. Infrared spectroscopy analysis demonstrated the effectiveness of maltodextrin as a polymer, generating microspheres that coated and protected anthocyanins. For the evaluation of antioxidant capacity, in vitro tests were carried out on the concentrate extract and the microencapsulated extract, using the DPPH technique, reaching a percentage of inhibition (73.22 and 40.98 percent) and obtaining values of 328.41 and 219.29 micromol (Trolox equivalent per gram of dry extract) respectively.