For a long time, residues from the extraction of vegetable oils from amazonian plants were discarded without any destination. The “patauá” is an oleaginous plant of the arecaceae family.
The appeal of the pharmaceutical industry is due to the physicochemical similarity to olive oil (Olea europaea), presenting high percentage of palmitic acid and antioxidant substances1
. The objective was to analyze the antioxidant properties of the industrial by-product and the thermal characterization of the standard lyophilized extract with the intention of technological development of vegetal extracts and valorization of a residual biomass from the agroindustry.
The antioxidant capacity of the lyophilized extract was performed by the DPPH radical scavenging activity. A solution of DPPH at 0.2mg/mL the ethanol was made. At the assay, 2.5 mL of each sample were added to 1.0 mL of the DPPH solution. The concentrations of the
extract were 5 mg/L; 2.5; 1.25, 0.625, 0.312 and absorbance of each solution were read at 518 nm. Pure ethanol was usede in the control of absorbance analysis and also created a standard
curve. For the determination of EC50% a graph was built. Calculated on the basis of the formula: DPPH sequestering% = [(Ac-Am) / Ac] x 100. The EC50 was expressed in μg/ml. The routine was used as the control positive, with EC50 = 6.5 μg/mL. The thermogravimetric curve
(TG) was acquired in the Shimadzu® brand DTG 60H calorimetric cell and the following conditions: Heating rate: 5ºC/min; Sample weight: approximately 5mg; Temperature range: 25-
600 ºC; Nitrogen dynamic atmosphere; Flow: 50.00mL /min; Cell material: Platinum. The results of the antioxidant activity were satisfactory, since at all concentrations showed positive results,
however, the calculation of EC50 determined that 209.04 ± 1.01μg/mL is able to reduce 50% of DPPH. In the thermal characterization, there were four stages of decomposition of lyophilized
extract (Table 01). It is concluded that the first step is loss of moisture and post-drying residue. The degradation of the bioactive components begins only in the second step (104.2 ºC), therefore, it is inferred the need to standardize this thermal range in the manipulation of this
extract. In the chromatographic test, piceatannol was detected, a chemical marker of the species with antioxidant properties already studied, boiling point 108ºC, information pertinent to
the importance of standardization in the manipulation of the “patauá” residue. Therefore, the by-product of the extraction of “patauá” oil presents biological potential, being an alternative source of bioactive products, state according to the sustainable development in the Amazon.