Dados do Trabalho

Título

Bioactive compounds and antioxidant activity of extracts obtained from butia (Butia catarinensis) seed cake

Introdução

Butia catarinensis is a palm tree predominant in Santa Catarina, Brazil. Butia fruits play an important role in the local economy and biodiversity but the species is at risk of extinction. After butia depulping, large amounts of seeds are obtained as co-products. In this work butia seeds were used as feedstock in a green biorefinery model for the sequential extraction of different fractions rich in oil, bioactive compounds (phenolics and carotenoids), sugars and proteins.

Material e Métodos

After the extraction of the "virgin" seed oil with a hydraulic press, a sequential extraction using pressurized technologies was performed in the cake. The extraction was done in the following order: supercritical fluid extraction – SFE (CO2, 50 °C, 250 bar) for the recovery of the remaining oil; pressurized ethanol extraction – PEE (50 °C, 100 bar) for recovery of the bioactive compounds; and pressurized water extraction – PWE (80 °C, 100 bar) for the protein. Proximal composition of the seed cake was determined by AOAC/AOCS official methods. Total phenolics, flavonoids, carotenoids, sugars and protein content in the extracts were measured via colorimetric assays. The antioxidant activities were determined via DPPH and ABTS assay. Oil quality was evaluated by p-anisidine and specific extinction AOCS official methods.

Resultados e Discussão

Yields ranging from 6 to 75% were obtained for the extracted fractions. The extract obtained by PEE were high in carotenoids (0.38 µg/mL), phenolics (25 mg GA/g) and sugars (20%). The extract obtained by PWE were high in proteins (26%). The SFE extract was low in carotenoids and phenolics. The residual oil recovered by SFE was of high quality, similar to the virgin oil. As expected, antioxidant activities in the PEE extract were much higher than in the other extracts (30% DPPH and 33% ABTS inhibition). In general, the studied biorefinery strategy showed to be efficient and selective for producing valuable fractions of different chemistry.

Conclusão

The selective extraction of high-value fractions of different chemical composition from butia seed cake showed to be effective, indicating that it may be used in a biorefinery model for the full use of butia fruits.