Bioprospecting Ultrasound-Assisted Phenolic Extracts from Psidium guineense: Antioxidant, Antimicrobial and UV Protection Potential

Authors:
Publisher website
Google Scholar
Abstract
Araçá (Psidium guineense Sw.) fruits were collected in Belém and freeze-dried for 72 h. An ultrasound-assisted extraction method was optimized using a central composite design (23) to evaluate the effects of ethanol concentration, solid-liquid ratio (SLR), and extraction time on total phenolics content (TPC) and antioxidant activity (2,2-diphenyl-1-picrylhydrazyl (DPPH) precentage of radical inhibition). A predictive polynomial model established at a 95% confidence level indicated optimal parameters of 25% ethanol, a 1:5 SLR, and a 10-min extraction time, yielding 304.6 ± 7.7 mg GAE g-1 of TPC and 59.5 ± 1.7% DPPH inhibition. The optimized extract also inhibited β-carotene lipid peroxidation with an IC50 value (half maximal inhibitory concentration) of 20.9 µg mL-1 and presented a sun protection factor of 16.0 ± 1.0. It contained substantial amounts of total flavonoids and carotenoids: 309.2 ± 17.7 mg QE g-1 and 108.2 ± 11.1 µg g-1, respectively. Liquid chromatography-electrospray ionization ion trap mass spectrometry (LC-MS/MS) analysis annotated key bioactive compounds, including quinic acid, ellagic acid, valoneic acid dilactone, and caffeoyl-quinic acid, these compounds are responsible for the antioxidant potential. Additionally, the extract demonstrated a bactericidal effect against Staphylococcus aureus, highlighting its potential use as an antiseptic. The bioprospecting of extract supports the potential for new industrial applications of P. guineense fruits, particularly within the cosmetic sector.