Extração de compostos bioativos da polpa de pequi (Caryocar brasiliense Camb.): avaliação do pré-tratamento e de solventes verdes

Abstract

Pequi (Caryocar brasiliense Camb.), known as the “gold” or “king” of the cerrado, reinforces the income generation potential for the local population due to its high nutritional value, mainly due to its high lipid content, antioxidant capacity of pulp and seed, in addition to the high carotenoid content. However, the presence of enzymes naturally present in this fruit, such as lipase, peroxidase and polyphenol oxidase, negatively affects the effectivenessin obtaining bioactive compounds. Therefore, this research aimed to extract bioactive compounds, aiming for less oil extraction and using “green solvents”, from wet pequi pulp and dry pequi pulp with lower enzyme activity. Studies with thermal pre-treatments applied tothe mesocarp with spiny endocarp at 121 °C/2 min, in an autoclave, obtained better inactivation of the enzymes lipase, peroxidase and polyphenol oxidase, without significant changes (P>0.05) in the color attributes (L* = 59.40±0.36; C*=48.44±2.98; ho=75.23±0.70). Extraction solvents (ethanol, ethanol: acetone and acetone), under stirring (250 rpm) at 40 °C for 4h to obtain extracts in order not to promote the degradation of the compounds of interest and avoid oil extraction. The antioxidant capacity was determined via DPPH and ABTS and the content of carotenoids and phenolic compounds were also quantified in order to evaluate the best scenario to obtain extracts with the greatest amount of bioactive compounds. The results were promising both in enzymatic inactivation, generating minimal degradation of bioactive compounds, and in the use of green solvents for the extraction of antioxidants, highlighting acetone and the use of wet pulp to obtain high levels of carotenoids (262,74 μgof α-carotene/100g and 282.67 μg of β-carotene/100g).