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This research aimed to propose a protocol for the processing of whole persimmon juice and to evaluate the effects of ultrasound treatment in relation to microbiological, sensory, and antioxidant aspects. The persimmon juice was submitted to freeze concentration, and the physical-chemical, total phenolic compounds (TPC), and antioxidant capacity were investigated. The sample treated with ultrasound (60% amplitude for 20 min) obtained a satisfactory reduction in total coliforms as well as the highest amount of TPC and total flavonoids compared with the control. This sample also showed a global preference in the sensory evaluation. Regarding the use of freeze concentration, two cycles of this process resulted in an increase in sugars, organic acids, and TPC. These results suggest that these nonthermal technologies can potentially be applied in relation to persimmon beverages, instead of the traditional pasteurization and concentration methods, to improve sensory quality and safety or to enhance functional properties. Novelty impact statement:This study suggests that ultrasound treatment applied in persimmon juice processing can reduce microbiological load while preserving phenolic compounds and antioxidant capacity. Freeze concentration is also a technology that can be incorporated by the beverage industry in order to improve functional and sensory properties.

Sterile bracts can represent 80% of Araucaria angustifolia pinecone and are a rich source of phenolic compounds. This study aimed to optimize the extraction of the phenolic compounds from Araucaria angustifolia bracts using response surface methodology; the bioactivity properties were also investigated. The effects of the ethanol concentration, solute/solvent ratio, and temperature in relation to the phenolic composition and antioxidant activity were evaluated. The quantification and identification of the individual phenolic compounds (using high-performance liquid chromatography) and their bioactivity were evaluated. The optimized extraction conditions, which detected gallic acid, catechin, epicatechin, quercetin, and kaempferol, were obtained using 60% ethanol at a ratio of 1:38 (w/v) and a temperature of 80 °C. The extract showed high levels of phenolic classes and antioxidant activity. The extract also showed an inhibitory activity for pathogenic (approximately 80%, 10,000 µg/mL) and lactic acid (27.9%, 15,000 µg/mL) bacteria strains. The α-glucosidase inhibitory activity was approximately ten times greater than acarbose, demonstrating its high antiglycemic potential. No antioxidant and anti-inflammatory cellular activity were determined; however, a high cytotoxicity for non-tumor cells and the antiproliferative activity against the tumor cells were observed. Overall, the phenolic extract showed promising action in relation to the fight against the diseases related to oxidative stress and, hopefully, the application of the safe concentrations of the extract, based on bioavailability assays, can be verified.