Optimization Of Ultrasound-assisted Extraction Research Articles

Optimization of ultrasound-assisted extraction of polyphenols from globe artichoke (Cynara scolymus L.) bracts residues using response surface methodology [pdf

BACKGROUND The globe artichoke (Cynara scolymus L.) is a rich source of phenolic compounds which may be extracted by ultrasound technology and used as a medicinal alternative. The objective of this work was to determine the radiation amplitude (%), ethanol concentration (%), and time extraction (min) required to guarantee an elevated content of polyphenol compounds. METHODS The optimal extraction conditions were assessed through the Box-Wilson design and by applying Composite Face Centered (CCFC) and total phenolic compounds (TPC) as the response variables. RESULTS A quadratic model was adequate, with R2 = 0.993. The optimal conditions were a radiation amplitude of 97%, an ethanol concentration of 53%, and an extraction time of 9.7 min. The optimized extract of artichoke bracts (Cynara scolymus L.) showed a TPC of 25.13 (±0.030) mg GAE/g, an antioxidant activity DPPH of 39.79 (±0.014) mmol Trolox equivalents (TE), and an antioxidant capacity TEAC of 33.98 (±0.03) mmol Trolox equivalents. CONCLUSIONS The results showed values closely related to the expected values, indicating that the models were well-developed.

Maximizing Contents of Phytochemicals Obtained from Dried Sour Cherries by Ultrasound-Assisted Extraction

Sour cherries were first dried by vacuum drying and then used as material for obtaining extracts rich in bioactive compounds by ultrasound-assisted extraction (UAE). The first step was to apply a factorial design for the preliminary experiments to determine the most influential UAE factors, and thus the three studied parameters were chosen as the most suitable for the design of the main experiment (temperature, liquid–solid ratio and ethanol concentration). In this part, the contents of total phenols and the total content of monomeric anthocyanins were taken for responses. For the further optimization of UAE, experimental design (face-centered) was applied, and the yield, total phenolics, flavonoid content and content of monomeric anthocyanins and antioxidant activity (DPPH, ABTS and FRAP assays) were analyzed. Temperature (40–80 °C), ethanol concentration (40–80%, w/w) and liquid–solid ratio (10–30 mL/g) were investigated as independent variables. The obtained experimental results were fitted to a second-order polynomial model and analysis of variance was used to determine the fit of the model and the optimal conditions for investigated responses. High quality extracts with high concentrations of polyphenols and anthocyanins were also obtained, which could be used as food additives.

Optimization of ultrasound-assisted extraction of turkish propolis and characterization of phenolic profile, antioxidant and antimicrobial activity

This study aimed to determine optimum conditions of the ultrasound assited extraction (UAS) parameters for different solvent types by using response surface methodology (RSM) and Box- Behnken design. The model parameters namely, time, temperature and ultrasound power significantly affected TPC value of the propolis extract (P < 0.05). The optimum process parameters were determined as 2.95 min, 58.61 °C and 615.26 W for ethanol, 3 min, 60°C and 580 W for dimethyl sulfoxide (DMSO), 3 min, 59 °C and 591 W for Propylene glycol (PG) and 2.70 min, 59.19 °C and 591.73 W for distilled water (DW). The extracts obtained from optimum conditions were compared with conventional solvent extraction methods (CSE). The chrysin was determined as a major phenolic compound and its value significantly differed based on the extraction and solvent types (P < 0.05). This study suggested that the ethanolic extracts obtained from UAS could be used as natural antimicrobial and antioxidant source.

Ultrasound-Assisted Extraction Optimization of Proanthocyanidins from Kiwi (Actinidia chinensis) Leaves and Evaluation of Its Antioxidant Activity.

Using ultrasound (US) in proanthocyanidin (PA) extraction has become one of the important emerging technologies. It could be the next generation for studying the US mechnophore impact on the bioactive compound’s functionality. The objective of this study was to demonstrate the potential of US treatment on PAs extracted from kiwifruit (Actinidia chinensis) leaves, and to provide a comprehensive chemical composition and bioactivity relationship of the purified kiwifruit leaves PAs (PKLPs). Several methods like single-factor experiments and response surface methodology (RSM) for the four affected factors on US extraction efficiency were constructed. HPLC-QTOF-MS/MS, cytotoxicity analysis, and antioxidant activity were also demonstrated. In the results, the modeling of PA affected factors showed that 40% US-amplitude, 30 mL/g dry weight (DW) solvent to solid ration (S/S), and 70 °C for 15 min were the optimum conditions for the extraction of PAs. Furthermore, PKLPs exhibited significant radical scavenging and cellular antioxidant activity (p < 0.05). In conclusion, this study’s novelty comes from the broad prospects of using US in PKLP green extraction that could play an important role in maximizing this phytochemical functionality in drug discovery and food science fields.

Optimization of ultrasound-assisted extraction and the antioxidant activities of Sidaguri (Sida rhombifolia)

Sidaguri (Sida rhombifolia) is widely distributed in tropical and subtropical regions and has been reported to possess many bioactive compounds that are beneficial for human health, including polyphenolics having antioxidant activities. The objective of this study was (1) to optimize ultrasound-assisted extraction (UAE) of Sidaguri and (2) to evaluate antioxidant activities of extracts resulting from the optimized condition using radical scavenging assay of 2,2′-diphenil-1-picrylhydrazyl (DPPH) and 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid. The optimum UAE conditions obtained were solvent to solid ratio of 26:1, temperature of extraction of 45.45°C, methanol concentration of 42%, power of sonication of 86%, and time of extraction of 5 minutes. Sidaguri obtained from locations of Kretek and Ngemplak had the highest radical scavenging activity accounting for 83.69% ± 0.30% and 82.95% ± 0.49%, respectively.

Optimization of Ultrasound-Assisted Extraction of Bioactive Compounds from Pelvetia canaliculata to Sunflower Oil

In this study, Pelvetia canaliculata L. macroalga, collected from the Atlantic Portuguese coast, was used as a source of bioactive compounds, mostly antioxidants, to incorporate them in sunflower oil with the aim of increasing its biological value and oxidative stability. The lyophilized alga was added to the oil, and ultrasound-assisted extraction (UAE) was performed. Algae concentration and UAE time varied following a central composite rotatable design (CCRD) to optimize extraction conditions. The following parameters were analyzed in the oils: oxidation products, acidity, color, chlorophyll pigments, carotenoids, flavonoids, total phenolic content, antioxidant activity by DPPH (2,2-diphenyl-1-picrylhydrazyl) and FRAP (ferric reducing antioxidant power) assays, and sensory analysis. Extraction conditions did not affect the acidity and the amount of oxidation products in the oil. Chlorophylls and carotenoid contents increased with algae concentration, while flavonoid extraction did not depend on algae content or UAE time. Total phenolics in the oil were highly related only to FRAP antioxidant activity. Storage experiments of supplemented oil (12.5% algae; 20 min UAE) were carried out under accelerated oxidation conditions at 60 °C/12 days. Antioxidant activity (FRAP) of supplemented oil was 6-fold higher than the value of non-supplemented oil. Final samples retained 40% of their initial antioxidant activity. The presence of algae extracts contributed to the increased oxidative stability of sunflower oil.

Screening and process optimization of ultrasound-assisted extraction of main antioxidants from sweet tea (Lithocarpus litseifolius [Hance] Chun)

Sweet tea (Lithocarpus litseifolius [Hance] Chun) is an herbal tea with multiple health benefits due to its main bioactive compounds. In this work, the DPPH-spiking test based on high-performance liquid chromatography (DPPH-spiking HPLC) was applied to precisely screen antioxidants from sweet tea. Three main antioxidants, including isoquercitrin, phloridzin, and trilobatin, were screened out from sweet tea. Furthermore, their antioxidant capacities were verified by the DPPH radical scavenging assay, and found their antioxidant capacities in the order of isoquercitrin > trilobatin > phloridzin. Ultrasonic-assisted extraction (UAE) was applied to optimize and extract the screened antioxidants, and the optimal extraction conditions were ethanol concentration of 69.0%, sample-to-liquid ratio of 18.0 w/v, extraction time of 18.4 min, extraction temperature of 25 °C, and ultrasonic power of 450 W, yielding 17.1 ± 1.26 mg/g isoquercitrin, 34.8 ± 1.49 mg/g phloridzin, and 163 ± 1.73 mg/g trilobatin. The antioxidant capacities of the extracts based on UAE (11.5 ± 0.04 mg ascorbic acid equivalent/g DW) was much higher than the extracts based on maceration extraction (7.9 mg ± 0.02 ascorbic acid equivalent/g DW). Moreover, it was found that trilobatin, isoquercitrin, and phloridzin accounted for 30.9%, 24.9%, and 5.33% of the total antioxidant capacities of the extracts under the optimal extraction conditions, respectively. Therefore, DPPH-spiking HPLC analysis combined with UAE is an effective method for the screening and extracting of the antioxidants in sweet tea, which should have potential applications in the development of functional foods.

Optimization of ultrasound assisted extraction of abalone viscera protein and its effect on the iron-chelating activity

This study aims to investigate effects of ultrasound assisted extraction on the abalone viscera protein extraction rate and iron-chelating activity of peptides. The optimal conditions for ultrasound assisted extraction by response surface methodology was at sodium hydroxide concentration 14 g/kg, ultrasonic power 428 W and extraction time 52 min. Under the optimal conditions, protein extraction rate was 64.89%, compared with alkaline extraction of 55.67%. The iron-chelating activity of peptides affected by ultrasound technology was further evaluated by iron-chelating rate, FTIR spectroscopy and LC-HRMS/MS. Alcalase was the suitable enzyme for the preparation of iron-chelating peptides from two abalone viscera proteins, showing no significant difference between their iron-chelating rate of 16.24% (ultrasound assisted extraction) and 16.60% (alkaline extraction). Iron binding sites from the two hydrolysates include amino and carboxylate terminal groups and peptide bond of the peptide backbone as well as amino, imine and carboxylate from side chain groups. Moreover, 24 iron-chelating peptides were identified from hydrolysate (alcalase, ultrasound assisted extraction), which were different from the 27 iron-chelating peptides from hydrolysate (alcalase, alkaline extraction). This study suggests the application of ultrasound technology in the generation of abalone viscera-derived iron-chelating peptides which have the ability to combat iron deficiency.

Ultrasound-assisted extraction of Osmanthus fragrans fruit oil and evaluation of its fatty acid composition, physicochemical properties and antioxidant activity

In this work, optimization of ultrasound-assisted extraction (UAE) of Osmanthus fragrans (OF) fruit oils from four representative species of OF groups was firstly performed. A Box-Behnken design was applied to investigate and optimize the process variables. Among them, the specie of OF var. latifolius Makino (OFL) had the highest oil yield (18.53 %) by UAE under the optimal conditions with an ultrasound extraction time of 33 min, ultrasound temperature of 52 ℃ and liquid-to-solid ratio of 12 mL/g. Furthermore, the fatty acid composition, physicochemical characteristics, and antioxidant activity of OFL fruit oil extracts obtained through UAE and Soxhelet extraction (SE) were determined and compared. The results demonstrated that the oil yield and fatty acid composition between UAE and SE were similar, while the oil obtained by UAE displayed superior physicochemical properties and antioxidant activity. These findings suggest that UAE represents an effective method for OF fruit oil extraction.

Optimization of Ultrasound-Assisted Extraction of Peony Seed Oil with Response Surface Methodology and Analysis of Fatty Acid

Optimization of Ultrasound-Assisted Extraction of Peony Seed Oil with Response Surface Methodology and Analysis of Fatty Acid

Optimization of Ultrasound-Assisted Extraction of Phenolics from Sideritis raeseri Using Response Surface Methodology.

In this study we define the optimal conditions for ultrasound-assisted extraction of bioactive polyphenols from S. raeseri aerial parts using response surface methodology. The influence of ethanol concentration (10–90%), extraction temperature (20–80 °C), extraction time (10–60 min), and solid-to-solvent ratio (1:10–1:50) on total phenolic content as well as on content of individual flavonoids, and hypolaetin and isoscutellarein derivatives was studied. For the experimental design, a central composite design was chosen. In the obtained extracts, the following ranges of targeted compounds were detected: total phenol from 19.32 to 47.23 mg GAE/g dw, HYP from 1.05 to 11.46 mg/g dw, ISC 1 from 0.68 to 10.68 mg/g dw, and ISC 2 from 0.74 to 15.56 mg/g dw. The optimal extraction conditions were set as: ethanol concentration of 65%, extraction time of 50 min, extraction temperature of 63 °C, and solid-to-solvent ratio of 1:40. Contents of TP, HYP, ISC 1, and ISC 2 in optimal extracts were 47.11 mg GAE/g dw, 11.73 mg/g dw, 9.54 mg/g dw, and 15.40 mg/g dw, respectively. Experimentally set values were in good agreement with those predicted by the response surface methodology model, indicating suitability of the used model, as well as the success of response surface methodology in optimizing the conditions of the extraction.

Development of a Natural Preservative from Chestnut Flowers: Ultrasound-Assisted Extraction Optimization and Functionality Assessment

This study was carried out with the aim of optimizing the ultrasound-assisted extraction (UAE) of phenolic compounds from male chestnut flowers (C. sativa Mill) to develop a bioactive extract with potential to be used as a natural antioxidant preservative ingredient in the food industry. Time (t, 1–39 min), solvent concentration (S, 0–100%), and ultrasonic power (P, 5–500 W) were used as the independent variables for a 5-level experimental circumscribed central composite design (CCCD) coupled with response surface methodology (RSM) to optimize the extraction of phenolic compounds by UAE. Regarding the variables, the three showed a significant effect on the extraction of phenolic compounds. The content of phenolic compounds (including flavonoids and tannins) and the extraction yield (extract weight gravimetrically assessed) were the response criteria for the optimization. Based on the statistically validated predictive polynomial models, it was possible to reach a maximum content of phenolic compounds at the global optimal conditions of 24 ± 3 min, 259 ± 16 W, and 51 ± 7% ethanol. Additionally, pentagalloyl-glucoside and trigalloyl-hexahydroxydiphenoyl-glucoside were the major phenolic compounds identified. The optimized extract was then analyzed for their biological properties. The bioactive potential of the chestnut flower extract obtained under these optimized conditions was evaluated using in vitro assays for antioxidant, anti-inflammatory, and antimicrobial activity, as well as cytotoxicity and hepatotoxicity tests. The results revealed that the enriched extract has antioxidant, antitumoral, and anti-inflammatory activities without toxicity issues. Overall, this study allowed to define the optimal conditions for the extraction of phenolic compounds from chestnuts male flowers by UAE, to obtain an enriched extract with biological properties that could be further used as a natural antioxidant ingredient with applications on functional foods.

Modelling and Optimization of Ultrasound-Assisted Extraction of Phenolic Compounds from Black Quinoa by Response Surface Methodology.

Phenolic compounds are currently the most investigated class of functional components in quinoa. However, great variability in their content emerged, because of differences in sample intrinsic and extrinsic characteristics; processing-induced factors; as well as extraction procedures applied. This study aimed to optimize phenolic compound extraction conditions in black quinoa seeds by Response Surface Methodology. An ultrasound-assisted extraction was performed with two different mixtures; and the effect of time; temperature; and sample-to-solvent ratio on total phenolic content (TPC) was investigated. Data were fitted to a second-order polynomial model. Multiple regression analysis and analysis of variance were used to determine the fitness of the model and optimal conditions for TPC. Three-dimensional surface plots were generated from the mathematical models. TPC at optimal conditions was 280.25 ± 3.94 mg of Gallic Acid Equivalent (GAE) 100 g−1 dm upon extraction with aqueous methanol/acetone, and 236.37 ± 5.26 mg GAE 100 g−1 dm with aqueous ethanol mixture. The phenolic profile of extracts obtained at optimal conditions was also investigated by HPLC. The two extracting procedures did not show different specificities for phenolic compounds but differed in the extraction yield.

Optimization of Ultrasound-Assisted Extraction of Essential and Non-essential/Toxic Trace Metals in Vegetables and Their Determination by FAAS and ICP-OES: an Evaluation of Human Health Risk

Optimization of Ultrasound-Assisted Extraction of Essential and Non-essential/Toxic Trace Metals in Vegetables and Their Determination by FAAS and ICP-OES: an Evaluation of Human Health Risk

Optimization of Ultrasound-Assisted Extraction via Sonotrode of Phenolic Compounds from Orange By-Products.

Orange peel is the main by-product from orange juice industry. It is a known source of bioactive compounds, mostly phenolic compounds, and it has been widely studied for its healthy activities. Thus, this research focuses on the establishment of ultrasound-assisted extraction of phenolic compounds in orange peel using a sonotrode. For this purpose, a Box–Behnken design of 27 experiments was carried out with four independent factors—ratio ethanol/water (v/v), time (min), amplitude (%), and pulse (%). Quantitative analyses of phenolic compounds were performed and the antioxidant activity was measured by ABTS and DPPH methods. The validity of the experimental design was confirmed by ANOVA and the optimal sonotrode extraction conditions were obtained by response surface methodology (RSM). The extracts obtained in the established conditions were analyzed by High Performance Liquid Chromatography (HPLC) coupled to mass spectrometer detector and 74 polar compounds were identified. The highest phenolic content and antioxidant activity were obtained using 45/55 ethanol/water (v/v), 35 min, amplitude 90% (110 W), and pulse 100%. The established method allows an increment of phenolics recovery up to 60% higher than a conventional extraction. Moreover, the effect of drying on phenolic content was also evaluated.

Optimization of Ultrasound-Assisted Extraction of Anti-Glycation Agents from Ecklonia cava

ABSTRACT Ultrasound-assisted extraction conditions were optimized to improve the extraction of advanced glycation end products (AGEs) inhibitors from Ecklonia cava extracts using response surface methodology. Conditions considered were extraction temperature (30–70°C), ethanol concentration (20–100%), and extraction time (10–50 min). Dependent variables were dieckol content, yield, and degree of AGEs inhibition measured in three anti-glycation assay models; namely, bovine serum albumin (BSA)-fructose (Fru), BSA-methylglyoxal (MGO), and BSA-glyoxal (GO). Overall, dieckol content increased, but AGEs formation and yield decreased, with increasing ethanol concentration. In the BSA-MGO model, AGEs inhibition decreased with increasing extraction temperature. The four-dimensional graphs were superimposed to select optimum conditions. The optimum conditions were determined as 50–60°C of extraction temperature, 70%–85% of ethanol concentration, and 25–35 min of extraction time. The suitability of the prediction model was evaluated by comparing the actual and predicted values of responses, and the results confirmed that our prediction model is suitable. IC50 of Ecklonia cava extract against BSA-Fru, BSA-MGO, and BSA-GO was 0.44, 0.56, and 0.73 mg/mL, respectively. The AGEs inhibition effect of Ecklonia cava extract in the BSA-MGO model was better than that of aminoguanidine at the same concentration.

Optimized ultrasound-assisted extraction of total polyphenols from Empetrum nigrum and its bioactivities

Optimization of ultrasound-assisted extraction (UAE) of total polyphenols (TPP) from Empetrum nigrum aerial parts was carried out by response surface methodology (RSM). The optimum UAE conditions of extraction time, extraction temperature, ethanol concentration, and solvent-to-material ratio were 21.38 min, 42.32 °C, 61.93% and 53.29:1 mL/g, respectively. Under the optimum conditions, the extraction yield of TPP was 32.17 ± 0.46 mg/g, which was 1.29–1.44 folds to those by the conventional extraction methods. In addition, the bioactivities of the extracts were investigated. Antioxidant activity test by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay revealed that the TPP extracts had a high potential for free radical scavenging activity. The TPP extracts showed remarkable antibacterial activity against both Gram-positive and Gram-negative strains, especially against Gram-positive strains. The evaluation of antitumor activity by the MTT assay and flow cytometric analysis indicated that the TPP extracts significantly inhibited B 16F 10 melanoma cell proliferation and effectively induced apoptosis of melanoma cells. These results demonstrate that E. nigrum aerial parts are rich in TPP and show great application potential in the pharmaceutical industry.

Optimization of Ultrasound-Assisted Extraction for Triterpene Compounds from Centella asiatica Using Response Surface Methodology

Optimization of Ultrasound-Assisted Extraction for Triterpene Compounds from <i>Centella asiatica</i> Using Response Surface Methodology

Optimization of Ultrasound-Assisted Extraction of Phloretin and Other Phenolic Compounds from Apple Tree Leaves (Malus domestica Borkh.) and Comparison of Different Cultivars from Estonia

Polyphenolic compounds, plant secondary metabolites essential for plant survival, are known for their high antioxidant and anti-inflammatory activity. In addition, several polyphenols, such as phloretin, also have potential antiviral effects, making these compounds potential ingredients of biofunctional foods. A promising source for the extraction of phloretin is a by-product of apple production—apple tree leaves. Focusing on green technologies, the first aim of the present study was to optimize the direct ultrasound-assisted extraction conditions to gain the maximum yield of phloretin from air-dried apple leaves. For the optimization of process parameters, we applied the response surface method with Box–Behnken design. The optimal extraction conditions were extraction time 14.4 min, sonication amplitude 10% and 10 g of sample per 100 mL solvent (70% ethanol, w/w). Using these conditions, we assessed the content of individual and total polyphenolic compounds along with antioxidant activity in the leaves of different autumn and winter apple cultivars grown in Estonia. The analyses were carried out with chromatographic (HPLC-DAD-MS/MS) and spectrophotometric methods. The phloretin concentration ranged from 292 to 726 µg/g and antioxidant activity from 6.06 to 11.42 mg GA eq./g, these being the highest in the local winter cultivars ‘Paide taliõun’ and ‘Tellissaare’, respectively.

Preservation of Chocolate Muffins with Lemon Balm, Oregano, and Rosemary Extracts.

Muffins are snacks made from flour and chocolate and preserved with synthetic additives. Following consumer trends, the search for natural food additives has gained traction. Plants such as rosemary, lemon balm, and oregano were analyzed following an optimization of ultrasound assisted extraction, screened for their antioxidant and antimicrobial activity and incorporated in chocolate muffins, comparing them to synthetic preservatives over the course of 8 days. The nutritional profile, organic and fatty acids, soluble sugars, texture profile, external color and digital imaging of the muffin pores were analyzed. Slight changes were sought for the muffins incorporated with the natural extracts. By means of linear discriminant analysis, rosemary extract was considered the most promising extract to preserve the muffins due to its similarity to potassium sorbate, showing no changes in the muffins it was incorporated in, although it showed a lower amount of phenolic compounds when compared to lemon balm.