Optimization of the extraction of bioactive compounds from Clitoria ternatea L and evaluation of encapsulation by ionotropic gelation

Abstract

The aim of the study was to optimize the extraction of bioactive compounds from Clitoria ternatea L. followed by its encapsulation by ionic gelation. The extraction of the bioactive compounds, using water as solvent, was carried out with solid-liquid extractions at hot and room temperature, obtaining as a response factor the content of total phenolic compounds (TPC). The bioactive compounds of the extracts were evaluated based on the levels of TPC and total monomeric anthocyanins. Analyzes of physical, chemical, phytochemical and antioxidant potential were performed. Encapsulation was performed by ionic gelation. The capsules were evaluated by characterization and visual aspects. Simulated gastrointestinal digestibility was determined based on TPC bioaccessibility. There was no statistical difference (p ≤ 0.05) between the extracts. The quadratic mathematical model presented a correction coefficient, R² = 0.997 and R²adjust = 0.974. Hot extraction at 80°C 5 minutes-1 at a concentration of 0.008 g mL-1 showed a TPC of 23.91 ± 0.90 mg (EGA) g-1 and 0.97 ± 0.50 mg (MVE) g-1 for monomeric anthocyanins. For antioxidant potential, the values of ABTS, FRAP and β-carotene/linoleic acid were 84.86 ± 1.52 µM trolox g-1, 220.83 ± 3.69 µM ferrous sulfate g-1 and 55, 95 ± 4.51%, respectively, for the same assay. The capsules had regular sizes and preserved color, high solubility (99%), encapsulation efficiency (76%). Bioaccessibility was 71% for lyophilized capsules, with greater intestinal absorption. Therefore, extracts and capsules of Clitoria ternatea L. possess bioactive compounds with an antioxidant profile.