Untargeted metabolomic profile of recovered bioactive compounds by subcritical water extraction of acerola (Malpighia emarginata DC.) pomace.

The untargeted metabolomics approach was used to compare the chemical profiles of acerola (Malpighia emarginata DC.) pomace extracts. The effect of drying the raw material before subcritical water extraction (SWE) at different temperatures on the yield, phenolic content, and in vitro antioxidant activity was evaluated. The results were compared with those obtained via Soxhlet and the findings suggest that SWE saves time (15 min) and solvent for extracting valuable components as compared to Soxhlet (6 h). An increase in temperature significantly improved the extraction yield (23.9 to 33.4 %), phenolic content (119.1 to 362 mgGAEg-1), and antioxidant activity, and higher values were obtained with SWE as compared to Soxhlet. The most abundant compounds detected by UPLC-ESI-QTOF-MS were ascorbic acid, kaempferol, quercetin, and isorhamnetin. The investigation of different moisture contents in the SWE showed promising results for eliminating the drying operation, saving time and energy, and obtaining highly concentrated phenolic-rich by-products.

Optimization of green PLE method applied for the recovery of antioxidant compounds from buriti (Mauritia flexuosa L.) shell.

Buriti fruit, with high content in carotenoids and antioxidant compounds, is well appreciated for its organoleptic characteristics. However, its shell, an agroindustrial residue, is mostly discarded. Therefore, to verify the technological potential of the buriti shells, the aim of this this study was to evaluated the antioxidant potential of the extracts from buriti shell obtained by pressurized liquid extraction (PLE) with ethanol/water mixtures. PLE optimization was performed by response surface methodology, with all results maximized at the conditions of 71.21 °C and with 91.58% of ethanol. The yields values varied from 16.82 to 25.16%, total carotenoids from 23.38 to 1056.59 µg ß-carotene equivalent g-1, total phenolic content from 143.37 to 172.02 mg Gallic acid equivalent g-1, DPPH from 31.04 to 48.62 µg.mL-1, and ABTS from 1.87 to 2.70 mmol TEAC. g-1. Therefore, considering the lack of studies about buriti shell, the present work provides valuable results that confirm the PLE relevance to enhance the value of this neglected material.