Dados do Trabalho

Título

USE OF RESPONSE SURFACE METHODOLOGY TO OPTIMIZE THE EXTRACTION OF BIOACTIVE COMPOUNDS FROM PURPLE ARAÇÁ BYPRODUCTS (Psidium myrtoides O. Berg)

Introdução

Purple araçá (Psidium myrtoides O. Berg.) and its byproducts stand out for their
bioactive potential among native Brazilian fruits. In this context, natural deep eutectic solvents
(NADES) are a sustainable alternative to conventional solvents for extraction. Therefore, using
the response surface methodology, this study sought to optimize the conditions for extracting
bioactive compounds from purple araçá waste using NADES in a water bath.

Material e Métodos

The variables
studied were the sample-solvent ratio (30-80 mg/mL), time (40-80 minutes) and temperature (45-
75°C), using a Box-Behnken design with 16 experiments. Total phenolic compounds (TPC) and
in vitro antioxidant capacity (ABTS+• e FRAP) were the responses evaluated. According to
preliminary investigations, the NADES used was prepared with choline chloride (ChCl), glycerol
(Gly), and water (molar ratio 1:1 and 20% water).

Resultados e Discussão

The results for TPC ranged from 26.77 to
683.17 mg of gallic acid (EAG)/g, while the antioxidant capacity ranged from 11.44 to 21.13
μmol TEAC/g for ABTS+• and from 10.07 to 20.18 μmol TEAC/g for FRAP. The sample-solvent
ratio (linear and quadratic) positively and significantly affected the responses, while the
temperature (linear) had a negative effect. The extraction time (linear) it negatively affected TPC
and ABTS+•, while it was insignificant for FRAP. The second-order polynomial model described
the experimental results well, with R² > 0.90 for all responses, indicating a good representation
of the observed variability. The analysis of variance (ANOVA) revealed a significant model (p ≥
0.05 for lack of fit). The optimized conditions, which achieved a desirability of 0.92, were a solidliquid ratio of 100 mg/5.5 mL, a temperature of 60 ℃, and an extraction time of 80 minutes. The
experimental values observed (CFT 592.32 mg EAG/g; ABTS+• 18.16 μmol TEAC/g; FRAP
17.17 μmol TEAC/g) in the optimum condition did not differ significantly from the values
predicted by the model, within a 95% confidence interval.

Conclusão

These results confirm the response
surface methodology's predictive capacity and effectiveness in optimizing the extraction of total
phenolic compounds from purple araçá waste. Moreover, the study demonstrates the potential of
NADES as a green extraction method, contributing to the development of sustainable practices
for valorizing agro-industrial byproducts.