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Pomegranate (Punica granatum L.) contains a high concentration of antioxidant and phenolic compounds. Pomegranate peel extracts at different concentrations were used as natural antioxidant to increased the lipid stability of fresh Tuscan sausages, comparing with sodium erythorbate (SE). Peels were subjected to ultrasound-assisted aqueous extraction and lyophilization. The extract was previously characterized throught phenol and flavonoids determination. The Tuscan Sausages were prepared, and color, pH, peroxides, and thiobarbituric acid reactive substances were assessed at 1, 15, and 30 days of storage, at a mean temperature of 5 ± 1 ºC and under a 12-hour light cycle/day. Sausages containing 0.05 and 0.1% of peel extract showed results similar to sodium erythorbate in lipid peroxidation. Sausages treated with pomegranate peel extracts showed an adequate global acceptability level in the sensory analysis. Pomegranate peel extracts are; therefore, a promising natural alternative for maintaining the lipid stability of Tuscan sausages, promoting the protection of the meat and in addition, being able to bring beneficial of the pomegranate to the human health.

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).

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ABSTRACT. Current research investigates the extraction process of total polyphenols from hibiscus (Hibiscus sabdariffa L.) and waxweed (Brazilian name: 'sete-sangrias') (Cuphea carthagenensis) and evaluates the antioxidant potential of their extracts. The extraction stage comprised investigation on the following parameters: i) solvents (acetone and ethanol) pure and fractioned with water; ii) variables (temperature, stirring, solvent ratio, time and pH). Total polyphenols were quantified by Folin-Ciocalteau reagent and antioxidant activity was determined by ABTS•+ (2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay. Results showed that, depending on experimental conditions, total phenolic contents for hibiscus and waxweed ranged between 460.86 mg GAE 100 g •+ e DPPH. Os resultados mostraram que o hibiscus e a sete sangrias tem um conteúdo significativo de polifenóis os quais podem ser extraídos em condições amenas de processo e, posteriormente, empregados como fontes naturais de antioxidantes em processos industriais.Palavras-chave: polifenóis, DPPH, extratos naturais.

The addition of fruit to the diet is very important, and we can use nutraceutical and functional foods for this supplement. A little-known fruit is a red pitaya (Hylocereus undatus) that has been widely reported to have a high antioxidant potential. In this study, we analyzed the in vitro and in vivo antioxidant capacity of microencapsulated pitaya extract on the behavior, antioxidant, and nervous system of the nematode Caenorhabditis elegans. The worms were treated with fruit extract before and after juglone-induced stress, to determine the protective or curative effects of pitaya. We have been evaluated cholinergic, antioxidant, and behavioral biomarkers. We have evidenced that the pulp of pitaya contains antioxidant compounds and can serve as a potential nutraceutical product. In addition, the fruit extract was effective in preventing and/or reverse the stress-induced damages, even at high levels of chemical stress at all evaluated parameters.

Five strains of filamentous fungi (Aspergillus niger strains NRRL 3122 and T0005007-2, Aspergillus oryzae CCT 3940, Aspergillus awamori NRRL 3112 and a Trichoderma sp.) were compared for their capacity to produce endo-polygalacturonase (endo-PG) in solid state fermentation. Maximum pectinolytic activity was reached in 72 h of growth, the best two fungal strains being A. niger T0005007-2 and A. oryzae CCT 3940. Three types of commercial purified pectin and four of unprocessed pectin (tangerine, orange, Tahiti lime and sweet lime rind) were used to assess the effect of pectin on the production of endo-PG by A. niger T0005007-2. Maximum pectinolytic activity was achieved using 6 and 10% (w/w) of purified pectin as inducer. Depending on the origin of the commercial pectin used as inducer, maximum endo-PG levels varied from 223 to 876 units per gram of dry medium (one endo-PG unit (U) was defined as the quantity of enzyme which caused a reduction in viscosity of 50% in a 1% w/v solution of pectin in 30 min), indicating that care should be taken when choosing this component of the medium. When the crude pectins were used as inducers at the same concentration as purified pectin, maximum endo-PG activities were 250-300 units/g. However, by increasing the amount of Tahiti lime rind to 50% (w/w) maximum endo-PG was 919 U/g, thus opening up the possibility of a low cost medium for endo-PG production.

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.