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The aim of this work was to produce an extract rich in different bioactive compounds from Arbutus unedo L. fruits to enhance its possible valorization and commercialization. The conditions of the main variables of maceration, microwave, and ultrasound assisted extractions (MA, MAE and UAE, respectively) were optimized and compared in terms of its composition (based on the total material extracted, total content in carbohydrates, phenolic and flavonoid compounds) and its preservative potential (based on the response of four in vitro antioxidant assays). The key variables of each extraction technique (time, temperature or power and hydroalcoholic mixture) were evaluated by specific experimental designs using response surface methodology. Mathematical models were developed and numerical optimal values for each extraction technique and response were achieved. Regarding the extraction of target compositional compounds, MAE was the most efficient, closely followed by MA. In terms of its preservative potential, MAE was the most suitable solution, but MA gave similar results at lower temperatures (~90 °C). Globally, MA and MAE were the best options conducting to optimal solutions using reduced amounts of ethanol. UAE required higher ethanol contents (~60%). The results showed alternatives to obtain extracts of A. unedo fruits, supporting their potential to be exploited at industrial level. [ABSTRACT FROM AUTHOR]

Nutrient-rich antioxidant ingredients were produced from tomato fruit wastes using a microwave-assisted extraction (MAE) process. Different conditions of extraction time ( t ), temperature ( T ), ethanol concentration ( Et ) and solid/liquid ratio (S/L) were combined in a circumscribed central composite design and optimized by response surface methodology. The model was statistically validated and used for prediction in the experimental range. Under the global optimal MAE conditions ( t = 20 min, T = 180 °C, Et = 47.4% and S/L = 45 g/L), it was possible to obtain an extraction yield of 75.5% and ingredients with high levels of sugars, proteins, phenolics, and flavonoids, and interesting antioxidant properties measured via ABTS + scavenging activity and oxidative haemolysis inhibition assay (OxHLIA). The antioxidant capacity of the extracts was lower compared to the one of commercial food additives. However, the sustainably developed ingredients may be used in the fortification and functionalisation of food, as well as for incorporation in feed products. Industrial relevance This study addresses current needs of the agri-food sector, namely the recycling of plant wastes and production of valuable extracts for the food/feed industry. A MAE process was developed and optimized to maximize the recovery of nutrients and antioxidants from tomato fruit wastes. The optimum processing conditions established in this study allowed a high extraction yield and reduced solvent consumption. MAE can be considered as a sustainable alternative to conventional extraction methods. These findings will contribute to promote a more sustainable bioeconomy in the agro-food sector. [ABSTRACT FROM AUTHOR]

This study compares three extraction techniques (maceration, microwave and ultrasound) for catechin recover from Arbutus unedo fruit extracts. To obtain the conditions that maximize catechin extraction yield, a response surface methodology was applied using a 3-level full factorial Box–Behnken design in which the processing time (t), temperature (T), ultrasonic power (W) and ethanol percentage (Et%) were the relevant independent variables with the response (catechin content, mg/g dw) measured by HPLC-PDA. A fixed solid/solvent ratio of 50 g/L was used in all techniques. Maceration and microwave extractions were found to be the most effective methods, capable of yielding 1.38 ± 0.1 and 1.70 ± 0.3 mg/g dw of catechin, respectively at the optimal extraction conditions. The optimal conditions for maceration were 93.2 ± 3.7 min, 79.6 ± 5.2 °C and 23.1 ± 3.7% of ethanol, while for the microwave extraction were 42.2 ± 4.1 min, 137.1 ± 8.1 °C and 12.1 ± 1.1% of ethanol. Comparatively with maceration, the microwave system was a faster solution, conducting to slightly higher catechin yields, but using higher temperatures to reach similar values. The ultrasound method was the least effective solution, yielding 0.71 ± 0.1 mg/g dw of catechin at 42.4 ± 3.6 min, 314.9 ± 21.2 W and 40.3 ± 3.8% ethanol. The results highlight the potential of using A. unedo fruits bio-residues as a productive source of catechin. [ABSTRACT FROM AUTHOR]

An ultrasound rapid and low-cost procedure for anthocyanin-based colorants from Prunus spinosa L. fruit epicarp was developed, and the advantages were compared with conventional heat-based extraction. To obtain the conditions that maximize anthocyanins' extraction, a response surface methodology was applied using the variables of time, temperature, and ethanol content, in the case of heat extraction, whereas for ultrasound assisted extraction, temperature was replaced by ultrasound power. Two anthocyanin compounds were identified by HPLC-DAD-ESI/MS—namely, cyanidin 3-rutinoside and peonidin 3-rutinoside. The responses used were the extraction yield and the content of the identified anthocyanins. Ultrasound extraction was the most effective method at 5.00 ± 0.15 min, 400.00 ± 32.00 W, and 47.98% ± 2.88% of ethanol obtaining 68.60% ± 2.06% of extracted residue, with an anthocyanin content of 18.17 mg/g (extract-basis) and 11.76 mg/g (epicarp-basis). Overall, a viable green process was achieved that could be used to support pilot-scale studies for industrial production of anthocyanin-based colorants from P. spinosa fruit epicarp. [ABSTRACT FROM AUTHOR]

The goal of this study was to compare anthocyanin extraction from Arbutus unedo L. fruits, by using two techniques assisted by different energy sources, heat and ultrasound. In order to obtain the conditions that maximize anthocyanin extraction, a response surface methodology was applied using the circumscribed central composite design of three variables with five levels. Three anthocyanin compounds were identified by HPLC-DAD-ESI/MS, being cyanidin-3-glucoside the main molecule. Heat assisted extraction proved to be the most effective method at 5 min, 90 °C and 80% of ethanol, yielding 51.2% of extract, with a total anthocyanin content of 382.4 µg/g dried fruit, and 744.6 µg/g extract. These response values were slightly improved by studying the solid/liquid effect at the optimal conditions in dose-response format, showing steady extraction values from 5 to 40 g/L. Results show the possibility of using A. unedo fruits as a source of anthocyanin compounds for industrial applications. [ABSTRACT FROM AUTHOR]

Gomphrena globosa L. is a source of betacyanins, molecules with high colorant power. In order to replace conventional extraction techniques, microwave (MAE) and ultrasound assisted extraction (UAE) processes were optimized by the response surface methodology (RSM) to maximize the recovery of betacyanins from G. globosa . A five-level full factorial design of 24 combinations and 4 replicates was implemented for MAE and UAE. The optimum processing conditions for MAE ( t = 8 min; T = 60 °C; Et = 0%; and S/L = 5 g/L) conducted to an extraction yield of 39.6 ± 1.8 mg/g dry weight, while for UAE ( t = 22 min; P = 500%; Et = 0%; and S/L = 5 g/L) a value of 46.9 ± 4.8 mg/g was achieved, validating the UAE more suitable to obtain the target compounds. This technique can provide extracts rich in betacyanins and with high potential to be used as natural colorants. [ABSTRACT FROM AUTHOR]

The present study describes a novel mechanical process for the pigmented parts of Gomphrena globosa L. The effects of the variables of the maceration extraction of betacyanins have not been properly described. Therefore, this study also aims to optimize the conditions that maximize betacyanins extraction from G. globosa as an alternative source. Assisted by response surface methodology, an experimental design was developed for testing the extraction variables (time, temperature, ethanol-water proportion and solid-liquid ratio). The responses used were betacyanins quantification (by HPLC-PDA-MS/ESI and spectrophotometric analysis), the extraction-yield and the colour intensity of the produced powder. The betacyanins identified were gomphrenin and isogomphrenin II and III. The highest betacyanins content (∼45 mg/g) was obtained by 165 min, 25 °C, 0% of ethanol and 5 g/L of solid-liquid ratio. The betacyanins content from the floral parts of G. globosa is higher than those normally found in other sources highlighting its industrial application. [ABSTRACT FROM AUTHOR]

Ergosterol, a molecule with high commercial value, is the most abundant mycosterol in Agaricus bisporus L. To replace common conventional extraction techniques ( e.g. Soxhlet), the present study reports the optimal ultrasound-assisted extraction conditions for ergosterol. After preliminary tests, the results showed that solvents, time and ultrasound power altered the extraction efficiency. Using response surface methodology, models were developed to investigate the favourable experimental conditions that maximize the extraction efficiency. All statistical criteria demonstrated the validity of the proposed models. Overall, ultrasound-assisted extraction with ethanol at 375 W during 15 min proved to be as efficient as the Soxhlet extraction, yielding 671.5 ± 0.5 mg ergosterol/100 g dw. However, with n -hexane extracts with higher purity (mg ergosterol/g extract) were obtained. Finally, it was proposed for the removal of the saponification step, which simplifies the extraction process and makes it more feasible for its industrial transference. [ABSTRACT FROM AUTHOR]

Abstract In the present work microencapsulation was applied to an ergosterol enriched extract (EEE) from Agaricus bisporus L. and pure ergosterol (PE) using a complex coacervation process. The process was optimized following two steps: (i) using response surface methodology to optimize the conditions of temperature (T , 55 to 95 °C), protein-to-chitosan ratio (P/C , 0.5 to 10.5), maximizing yield (Y 1 , %, w/w), efficiency (Y 2 , %, w/w) and load (Y 3 , %, w/w); and (ii) using the dose-response methodology to optimize the ergosterol content (E) at the optimal conditions achieved in (i). The global optimal conditions for both cases were the same (T of 55 °C and a P/C of 0.5), but with maximized responses of Y 1 = 75.02%; Y 2 = 100.00%, Y 3 = 12.78%, and Y 1 = 19.19%; Y 2 = 100.00%, Y 3 = 15.87%, respectively. The effect of increasing ergosterol content led to the reduction of the microencapsulation yield, but with an increase in the ergosterol load and maintenance of the microencapsulation efficiency. Highlights • Complex coacervation as an efficient microencapsulation process for ergosterol. • Whey protein and chitosan from industrial wastes used in the encapsulation process. • Optimization of the coacervation process by Response Surface Methodology. • Coacervates with high yield, encapsulation efficiency and ergosterol load. • New functional ingredients compatible with food applications. [ABSTRACT FROM AUTHOR]

Abstract Due to its coloration, the fig (Ficus carica L.) peel, a by-product of fruit processing and/or consumption, is a potential source of anthocyanin compounds. In the present study different extraction techniques (heat, ultrasound, and microwave) were compared aiming to recover the anthocyanin pigments and optimize its extraction conditions. A response surface methodology tool with three factors and five levels for each factor was used according to a circumscribed central composite design. The variables tested for the heat and microwave extraction methods were time, temperature, and solvent proportion (ethanol/water ratio), meanwhile, for the ultrasound method, the variables tested were the ultrasonic power, time, and solvent proportion. The anthocyanin composition of the extract was determined by HPLC-DAD-ESI/MS, and the used criteria responses were: i) quantification of cyanidin 3-rutinoside (C) in the extracted residue (mg C/g R) and in the dried peel (mg C/g P dw), and the extraction yield of the obtained residue (g R/g P dw). Ultrasound extraction was the most effective method, yielding 3.82 mg C/g R at the optimal global extraction conditions (21 min, 310 W, and 100% of ethanol). Additionally, the solid-to-liquid ratio effect was studied at the optimal conditions, using a dose-response format, in view of its plausible transference to industrial level. For the ultrasound method, an increased non-linear relationship was observed for concentrations in the range 5 to 200 g/L, being the optimal solution close to 150 g/L. In brief, the obtained results show the potential of fig peels as a source of anthocyanin pigments, with potential uses in various industrial fields, such as food, pharmaceutical, and cosmetic. Graphical abstract Unlabelled Image Highlights • Recovery of anthocyanin pigments from Ficus carica L. by-products • Comparison of three different techniques for anthocyanin extraction maximization • Ultrasound assisted extraction was the most effective method • The optimal extraction conditions were 21 min, 310 W, and 100% of ethanol • The potential application of fig peels as a source of anthocyanins was highlighted. [ABSTRACT FROM AUTHOR]

The goal of this study was to compare the extraction of rosmarinic acid from Melissa officinalis L. using three techniques (heat- -, microwave- and ultrasound- assisted extraction). In order to obtain the conditions that maximize the rosmarinic acid extraction, a response surface methodology was applied using the circumscribed central composite design of three variables with five levels. The relevant independent variables used for the process optimization were time, temperature and ethanol–water proportion for heat-assisted- and microwave-extration, whereas for the ultrasound method the ultrasonic power was variable. The responses used as criteria were the amount of rosmarinic acid was determined by HPLC-DADand the extraction yield of the obtained residue. Ultrasound extraction proved to be the most effective method, capable of yielding 86.3 ± 4.1 mg rosmarinic acid/g plant per dry weight (dw) at the optimal extraction conditions (33.0 ± 3.2 min, 371.7 ± 19.3 W and 39.9 ± 1.4% of ethanol). According to the content of rosmarinic acid, microwave- and heat-assisted extractions techniques were less effective, producing 49.4 ± 2.3 (at 26.5 ± 2.1 min, 108.6 ± 10.2 °C and 25.5 ± 0.9% of ethanol) and 59.4 ± 2.2 (at 106.2 ± 5.1 min, 88.0 ± 2.9 °C and 34.5 ± 1.6% of ethanol), respectively. Additionally, the solid/liquid ratio effect at the optimal values in a dose–response format was studied in view of its plausible transference at industrial level, showing a decreasing non-linear pattern from 5 to 120 g/L. In brief, the obtained results highlight the potential applications of using the leaves from M. officinalis as a source of rosmarinic acid. [ABSTRACT FROM AUTHOR]

Response surface methodology was applied to optimize the recovery of ergosterol from an agroindustrial residue of Agaricus blazei Murrill, by comparing conventional (heat-assisted extraction, HAE) and more sustainable non-conventional approaches (ultrasound and microwave-assisted extractions, UAE and MAE, respectively). A circumscribed central composite design was employed to optimize and describe the interactive effects among variables of the HAE, MAE (time and temperature) and UAE systems (time and ultrasound power), and their performances compared with the standard soxhlet extraction system. The optimum conditions were predicted as 150 min, 81.6 °C for HAE, 30 min, 400 W for UAE, and 25 min, 134.6 °C, for the MAE system. The UAE system was identified as the most appropriate technique to obtain extracts with the highest amount of ergosterol, followed by MAE and HAE. Overall, these results demonstrate the potential of using the fruiting bodies of A. blazei as a suitable source to obtain ergosterol-rich extracts, which can be used as an ingredient for various bio-based industrial applications. Unlabelled Image • Agaricus blazei bioresidues were exploited to obtain ergosterol-rich extracts. • Response surface methodology was adopted to optimize extraction parameters. • Conventional extraction techniques were compared with non-conventional techniques. • Optimum extraction conditions for each technique were established. • The use of ultrasound assisted technology improved ergosterol extraction. [ABSTRACT FROM AUTHOR]