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In this work, microwave-assisted extraction (MAE) technique was developed for the extraction of total polyphenols from Physalis angulata. Several parameters of the MAE procedure (ethanol concentration, irradiation power, extraction time and liquid-to-solid ratio) were assessed through an experimental Box-Behnken design (four variables and three levels). Results indicated a variation from 3.74 to 0.03 mg GAE/g of extract (total polyphenol), 7.77 to 0.5 mg/L (gallic acid), 0.55 to 0.27 mg/L (ellagic acid), 0.26 to 0.02 mg/L (caffeic acid), 0.86 to 0.25 mg/L (rutin) and 2.43 to 0.89 mg/L (mangiferin), and different effects were observed depending on the compounds. In summary, MAE may be used as a suitable approach for the selective extraction of total polyphenols from Physalis angulata. PRACTICAL APPLICATIONSMicrowave-assisted extraction (MAE) is a potential technique to obtain total phenolic compounds from vegetable sources. This approach increases the yields and reduces the extraction time and the consumption of solvent compared with traditional extraction methods. Extract from Physalis angulata shows high polyphenol content and ethnopharmacological value which may be applied as preservative (in food industry) or due to its biological properties (antioxidant, antipyretic, analgesic and anti-inflammatory).

The main objective of this work was to investigate the extraction kinetics of total polyphenol content (TPC) from pitanga (Eugenia uniflora L.) through conventional maceration with solvent, evaluating the effect of temperature, plant‐to‐solvent ratio and ethanol percentage. In parallel, the mathematical modeling of experimental data was performed and a model that represents the kinetics profile of extraction with their respective response surface has been proposed. Ultrasound‐assisted technology was used to maximize the conditions that promote higher polyphenol content extracted using the conventional method, verifying posteriorly the antioxidant activity of the extract by DPPH (2,2‐diphenyl‐1‐picrylhydrazyl) radical‐scavenging assay. The results indicated that based on the regression coefficient (R2), it can be observed that the model predicted satisfactorily the extraction process and the use of ultrasound treatment promoted an increase of about 80.34% in TPC extracted compared with conventional method (from 16.79 to 30.28 mg GAE/g of plant). Extracts enriched with polyphenols showed antioxidant activity up to 48.84% for a concentration of 0.01 g/mL. In general, we concluded that use of ultrasound‐assisted technology is important to maximize the amount of total polyphenols extracted and accredits pitanga as a natural antioxidant source for use in food preservation and in human health. Practical Applications This work describes the practical procedures to obtain a new extract from pitanga (Eugenia uniflora L.), which can be used in different segments of food industry, as in bread baking, edible oils and among others. The results presented can guide the improvement of technique and proposes an interesting alternative for partial or full substitution of synthetic ingredients, increasing the quality of food.