Dados do Trabalho

Título

BOUGAINVILLEA SPECTABILIS AS A SOURCE OF BETACYANINS AND PHENOLIC COMPOUNDS: A MULTIVARIATE EXTRACTION

Introdução

The species Bougainvillea spectabilis originates from South America and its composition is characterized by the presence of betacyanins (red-violet pigments) and phenolic compounds (bioactives with antioxidant capacity in vitro).

Material e Métodos

With the objective of determining the optimal extraction condition, by ultrasound, of these compounds, a 2² multivariate planning was used with central and axial points, to evaluate the variables ethanol concentration and volume of extracting solution. The bracts were collected in the municipality of Pelotas, RS (31° 37' 21.202" S, 52° 30' 2.332" W), freeze-dried, crushed and sieved (0.60 mm). For extraction, 250 mg of sample was added with ethanol (UV-HPLC, Dynamic) according to the levels of the independent variables of the experimental design (0; 14.5; 50; 85.5 and 100% ethanol in water in the extracting solution) and extracting solution (7.5; 10; 16.25; 22.5 and 25 mL). They were then placed in an ultrasonic bath (QUIMIS, Q335D, São Paulo) at 70 W, for 15 minutes at 25 °C. The content of betacyanins and phenolic compounds in the experiments were subjected to analysis of variance to establish suitable mathematical models to predict the optimal extraction condition. All multivariate planning was performed in duplicate.

Resultados e Discussão

Values for betacyanins and phenolic compounds ranged from 0.00 ± 0.00 mg/100g to 548.49 ± 3.04 mg/100g and 425.24 ± 86.32 mg EAG/100g to 4215.75 ± 10.37 mg EAG/100g, respectively. Both models obtained significant regression for the quadratic model and only the model for phenolic compounds showed adjustment. Considering these factors, the optimal extraction condition was 50% ethanol in the extracting solution and a volume of 25 mL. The optimal extract obtained EC50 values of 2.77 ± 0.15 g lyophilized sample/g DPPH and 30020.01 ± 471.72 µMol Trolox/g lyophilized sample for ABTS.

Conclusão

The results indicate that ultrasound extraction guaranteed high concentrations of betacyanins and phenolic compounds. Bougainvillea spectabilis extract has a high content of natural pigments and antioxidant activity, with potential for application in the food, pharmaceutical and cosmetic industries.