Ultrasound-assisted Extraction Of Phenolic Compounds Research Articles

Ultrasound-Assisted Extraction of Phenolic Compounds from Celtuce (Lactuca sativa var. augustana) Leaves Using Natural Deep Eutectic Solvents (NADES): Process Optimization and Extraction Mechanism Research.

Natural deep eutectic solvents (NADESs), as emerging green solvents, can efficiently extract natural products from natural resources. However, studies on the extraction of phenolic compounds from celtuce (Lactuca sativa var. augustana) leaves (CLs) by NADESs are still lacking. This study screened the NADES L-proline-lactic acid (Pr-LA), combined it with ultrasound-assisted extraction (UAE) to extract phenolic compounds from CLs, and conducted a comparative study on the extraction effect with traditional extraction solvents. Both SEM and FT-IR confirmed that Pr-LA can enhance the degree of fragmentation of cell structures and improve the extraction rate of phenolic compounds. Molecular dynamics simulation results show that Pr-LA can improve the solubility of phenolic compounds and has stronger hydrogen bonds and van der Waals interactions with phenolic compounds. Single-factor and Box-Behnken experiments optimized the process parameters for the extraction of phenolic compounds from CLs. The second-order kinetic model describes the extraction process of phenolic compounds from CLs under optimal process parameters and provides theoretical guidance for actual industrial production. This study not only provides an efficient and green method for extracting phenolic compounds from CLs but also clarifies the mechanism of improved extraction efficiency, which provides a basis for research on the NADES extraction mechanism.

Optimization of ultrasound-assisted extraction of phenolic compounds from Populus nigra as potential myeloperoxidase inhibitors

Optimization of ultrasound-assisted extraction of phenolic compounds from Populus nigra as potential myeloperoxidase inhibitors

Ultrasound-assisted extraction of phenolic compounds from Moringa oleifera leaves by response surface methodology

Background: Moringa oleifera is a tree that grows in tropical and subtropical areas around the world. Its leaves, seeds, bark, roots, and flowers are used as ingredients in meals and medicinal applications. Moringa leaf extracts have been studied to contain antioxidant compounds such as phenolic molecules. Recent extraction techniques such as ultrasound and microwaves are alternatives to increase the extraction performance of phenolic compounds while preserving their antioxidant activity.Objective: The approach consisted of optimizing, using a Composite Central Design of Response Surface Methodology (CCD-RMS), the process conditions, for ultrasound-assisted extraction (UAE) of antioxidant phenolic compounds from Moringa oleifera leaves. Methods: A 33 CCD-RMS was used; three independent variables were studied: ethanol concentration (25%, 50%, 75%), time (10, 20, and 30 min), and temperature (25, 37.5, and 50°C). The results showed that the optimal UAE conditions were an ethanol concentration of 52.4%, extraction time of 3.2 min, and temperature of 58.5°C; under these conditions the phenolic content was 13.92±0.21 mg GAE/g sample the total flavonoid content was 10.60±0.06 mg QE/g sample, and 52.22±2.01% and 72.81±1.58% of DPPH• and ABTS•+ radicals were inhibited, respectively.Conclusion: This optimization will make it possible to assess better use of M. oleifera leaves as an antioxidant ingredient in functional food development.Keywords: Moringa oleifera, composite central design, optimization, flavonoids, phenols, antioxidant activity.

Optimization of ultrasound-assisted extraction of phenolic compounds and flavonoids from Hortia oreadicaleaf

Hortia oreadica is indiscriminated used by people from Cerrado. However, vegetable raw material quality is decisive in obtaining intermediate and final products. So, this study aimed to establish quality parameters of H. oreadica. For this, we performed the phytochemical screening of H. oreadicaleaf and identified the best extractive conditions for phenolic compounds and flavonoids using factorial experimental design, varying the alcoholic strength, extraction temperature, and solid/liquid ratio in the ultrasound-assisted extraction method. The optimum extraction condition for phenolic compounds and flavonoids was 60% alcoholic strength,40°C temperature, and a solid/liquid ratio of 8 mg/mL. Under this setting, the phenolic and flavonoid contents were 0.171 ± 0.002 mg/mL(predicted value = 0.165) and 0.087 ± 0.002 mg/mL(predicted value = 0.084), respectively. The optimized extraction parameters could be upscaled to develop pharmaceutical drugs or nutraceutical products from this non-traditional plant species using an eco-friendly approach.

Guadua angustifolia Kunth leaves as a source for bioactive phenolic compounds: Optimization of ultrasound-assisted extraction using response surface methodology and antioxidant activities

This study evaluated the ultrasound-assisted extraction of phenolic compounds from Guadua angustifolia leaves, along with their optimization using response surface methodology. The effects of two sonication process conditions were determined using a central composite experimental design, with three levels (low, medium, and high) evaluated for time (10, 20, and 30 min) and temperature (20 °C, 35 °C, and 50 °C). A total of 12 experiments with four replicates were conducted at the central point, with the total phenol and flavonoid contents determined using the Folin-Ciocalteu colorimetric method and complexation with AlCl3, respectively. The optimized extract was analyzed using ultra-performance liquid chromatography (UPLC), and the antioxidant capacity of the optimized extract was determined by DPPH• (2,2-Diphenyl-1-Picrylhydrazyl) and ABTS•+ (2,2′-Azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) assays. Extraction at 50 °C for 20 min was found to favor the extraction of phenol and total flavonoids. The experimental validation of the total phenol and flavonoid content produced values of 7.39 mg gallic acid equivalents per gram of dry matter and 1.55 mg quercetin equivalents per gram of dry matter, respectively. These values suggest that the extraction process is reproducible, with a relative standard deviation of 22.9 % and 14.1 %, respectively. The chromatographic profile showed that optimization favored the visualization of phenolic compounds compared to the non-optimized extract. The optimized extract had higher antioxidant capacity than the non-optimized extract, with values of 209.23 and 144.76 μmol Trolox per gram extract for the DPPH• and ABTS•+ techniques, respectively. Thus, the conditions evaluated in the ultrasound-assisted extraction were an efficient technique capable of extracting the maximum amount of phenolic compounds with antioxidant activity from the leaves of G. angustifolia, showing its potential application in various industries.

Solvent selection and effect of extraction conditions on ultrasound-assisted extraction of phenolic compounds from galangal (Alpinia officinarum)

This study aimed to identify the appropriate extraction solvent and investigate the effect of temperature (20–70 °C), time (5–60 min), solvent/solid ratio (5−40), ethanol/water concentration (10–90%) and ultrasound-assisted extraction conditions (ultrasound power of 10–90% and ultrasound cycle of 1–9) on total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and total flavonoid content (TFC) of galangal extracts. All extraction conditions studied had significant effect (p ≤ 0.05) on TPC, DPPH, ABTS and TFC. Ethanol/water (50%) binary solution was found as the most appropriate extraction solvent. Temperature of 25 °C, extraction time of 20 min, ethanol/water concentration of 50%, solvent/solid ratio of 10, ultrasound power of 50% and ultrasound cycle of 5 were determined to be the most efficient extraction conditions which yielded TPC of 66.89 mg GAE/g, DPPH of 49.01% inhibition, ABTS of 147.43 mM TE/ml and TFC of 148.22 QE/g. Significantly positive or negative, very high, strong and moderate Pearson correlation coefficients were obtained among TPC, DPPH, ABTS and TFC values. Pearson correlation analysis revealed that very high correlations (r ≥ 0.90) existed between DPPH and ABTS (r = 0.907, p ≤ 0.01), and TPC and TFC (r = 0.939, p ≤ 0.01) for the ethanol/water concentration, and between DPPH and ABTS (r = 0.944, p ≤ 0.01) for the ultrasound power. The current study showed that phenolic compounds with high antioxidant activity could be extracted from galangal using the ultrasound-assisted extraction conditions determined.

Ultrasound-assisted extraction of phenolic compounds from macadamia (Macadamia integrifolia) green peel: Purification, identification and antioxidant activities

China is one of the world's main producers of macadamia. The macadamia green peel (MGP), byproducts of industrial processing, are commonly discarded for use as fertilizer. In this study, the ultrasound-assisted extraction and purification process of phenolic compounds from MGP were optimized, and the identification and analysis of antioxidant activities of purified extracts were performed. Results indicated that the optimal extraction conditions were sonication power 140 W, solid-liquid ratio 1:45 g/mL, and extraction temperature 43 °C, and the total phenolic content (TPC) was 18.23 mg gallic acid equivalent (GAE)/g dry weight (DW). Among four purified fractions (PF1, PF2, PF3 and PF4) obtained by ADS17 resin, sixty phenolic compounds were identified and twenty-one phenolic compounds were quantified for the first time, of which PF2 showed the highest TPC (246.18 mg GAE/g DW), mainly including 3,4-dihydroxybenzaldehyde, vanillic acid, 4-hydroxybenzoic acid and gallocatechin. In addition, PF2 demonstrated excellent total antioxidant activity (ABTS, DPPH and FRAP assays were 2.16, 2.59, 1.96 mM Trolox equivalent/g DW, respectively) and cellular antioxidant activity (0.97 mM quercetin equivalent/g DW). The antioxidant activities showed significant positive correlated with the content of catechin and procyanidin B1. The results provide guidance for the industrial production and application of MGP.

Modeling and Optimization of Ultrasound-Assisted Extraction of Phenolic Compounds from Haloxylon Scoparium Aerial Parts

Modeling and Optimization of Ultrasound-Assisted Extraction of Phenolic Compounds from Haloxylon Scoparium Aerial Parts

Valorisation of goldenberry calyx: ultrasound-assisted extraction of phenolic compounds

Valorisation of goldenberry calyx: ultrasound-assisted extraction of phenolic compounds

Response Surface Methodology as an Experimental Strategy for Ultrasound-Assisted Extraction of Phenolic Compounds from Artichoke Heads.

The accurate quantification of phenolic compounds (PCs) in foods has become mandatory for a reliable estimation of PCs dietary intake. However, the extraction step of these molecules from the food matrix is a challenging and complex task. To manage the current lack of an official or generally accepted procedure for the recovery of phenolics, the application of statistical and mathematical tools, such as the response surface methodology (RSM), that allow the optimization of extraction parameters and the acquisition of the best output, has become the analytical approach of choice. The aim of this study was to apply an RSM-optimized ultrasound-assisted procedure to extract phenolic compounds from artichoke (Cynara cardunculus L. var. scolymus (L.) Hegi, cultivar "Campagnano") heads. The effect of extraction time, temperature, and solvent-to-sample ratio on the profile and content of phenolic acids and flavonoids was investigated. The total phenolic content was 488.13 ± 0.56 mg GAE 100 g-1 dry matter (dm) and total flavonoid content was 375.03 ± 1.49 mg CATeq 100 g-1 dm when the optimum extraction conditions were set. The HPLC analysis showed that caffeoylquinic acid derivatives (i.e., cynarin and 1,5-O-dicaffeoylquinic acid) were the main compounds in globe artichokes. Caffeic and p-coumaric acids were also identified. In regard to flavonoids, only the flavone luteolin-7-O-glucoside was identified.

Ultrasound-assisted extraction of phenolic compounds from blueberry leaves using natural deep eutectic solvents (NADES) for the valorization of agrifood wastes

The food industry demands novel green solvents for the extraction of bioactive compounds, particularly from residues of the agrifood industry. Herein, an ultrasound-assisted method has been developed for the environmentally friendly extraction of phenolic compounds from blueberry leaves using natural deep eutectic solvents (NADES). After the screening of multiple NADES, the best extraction efficiencies in terms of total phenol content and antioxidant activity were provided by NADES composed of lactate, sodium acetate, and water (3:1:2), and of choline chloride and oxalic acid (1:1). Using a Box–Behnken experimental design, the optimal extraction conditions were achieved by sonicating for 45 min at 65 °C and using solvent:sample ratios of 15 and 75 (v/w) for the NADES based on lactic acid and choline, respectively. Compared with conventional organic solvents, the use of these NADES composed of lactic acid and choline provided superior performance for the recovery of phenolic compounds (1.6-fold and 2.2-fold greater efficacy, respectively) and antioxidant compounds (1.6-fold and 2.8-fold greater efficacy, respectively). The chromatographic characterization of the extracts obtained under these optimized conditions evidenced that the lactic-based NADES enabled the extraction of a wide range of hydroxycinnamic acids and flavonol derivatives, whereas the choline-based NADES was selective towards the extraction of anthocyanins. These results indicate that the proposed method could represent an excellent green alternative for the recovery of phenolic compounds from plant materials and agrifood wastes, with improved extraction efficacy and/or selectivity compared to that provided by traditional organic solvents.

Ultrasonic-assisted extraction for phenolic compounds and antioxidant activity of Moroccan Retama sphaerocarpa L. leaves: Simultaneous optimization by response surface methodology and characterization by HPLC/ESI-MS analysis

This study was designed to optimize the ultrasound-assisted extraction of phenolic compounds and the antioxidant activity of Moroccan Retama sphaerocarpa extracts using response surface methodology (RSM). A central composite design has been conducted to investigate the effects of three factors: extraction period (X1), solvent concentration (X2), and solvent-to-material ratio (X3) on extraction yield, total phenolic content (TPC), flavonoids content (TFC), and antioxidant activity. The obtained results showed that the experimental values agreed with the predicted ones, confirming the capacity of the used model for optimizing the extraction conditions. The best extraction conditions for the simultaneous optimization were an extraction time of 38 min, a solvent concentration of 58%, and a solvent-to-material ratio of 30 mL/g. Under these conditions, the optimized values of yield, TPC, TFC, and DPPH-radical scavenging activity (DPPHIC50) were 18.91%, 154.09 mg GAE/g, 23.76 mg QE/g, and 122.47 μg/mL, respectively. The further HPLC/ESI-MS analysis of the obtained optimized extract revealed the presence of 14 phenolic compounds with piscidic acid, vitexin, and quinic acid as major compounds. These research findings indicate promising applications for efficiently extracting polyphenolic antioxidants, especially in the food industry.

High-intensity ultrasound-based process strategies for obtaining edible sunflower (Helianthus annuus L.) flour with low-phenolic and high-protein content

The sunflower Helianthus annuus L. represents the 4th largest oilseed cultivated area worldwide. Its balanced amino acid content and low content of antinutrient factors give sunflower protein a good nutritional value. However, it is underexploited as a supplement to human nutrition due to the high content of phenolic compounds that reduce the sensory quality of the product. Thus, this study aimed at obtaining a high protein and low phenolic compound sunflower flour for use in the food industry by designing separation processes with high intensity ultrasound technology. First, sunflower meal, a residue of cold-press oil extraction processing, was defatted using supercritical CO2 technology. Subsequently, sunflower meal was subjected to different conditions for ultrasound-assisted extraction of phenolic compounds. The effects of solvent composition (water: ethanol) and pH (4 to 12) were investigated using different acoustic energies and continuous and pulsed process approaches. The employed process strategies reduced the oil content of sunflower meal by up to 90% and reduced 83% of the phenolic content. Furthermore, the protein content of sunflower flour was increased up to approximately 72% with respect to sunflower meal. The acoustic cavitation-based processes using the optimized solvent composition were efficient in breaking down the cellular structure of the plant matrix and facilitated the separation of proteins and phenolic compounds, while preserving the functional groups of the product. Therefore, a new ingredient with high protein content and potential application for human food was obtained from the residue of sunflower oil processing using green technologies.

Optimization of ultrasound-assisted extraction of phenolic compounds from germinated deoiled flaxseed flour using response surface methodology

Optimization of ultrasound-assisted extraction of phenolic compounds from germinated deoiled flaxseed flour using response surface methodology

Ultrasound-Assisted Extraction of Phenolic Compounds from Different Maturity Stages and Fruit Parts of Cordia dodecandra A. DC.: Quantification and Identification by UPLC-DAD-ESI-MS/MS

In the present work, the total phenolic content (TPC), total flavonoids content (TFC), antioxidant activity, and phenolic profile from pulp (PU) and peel (PE) extracts obtained from the ciricote (Cordia dodecandra A. DC.) fruit by ultrasound-assisted extraction (UAE) in immature (IM), semimature (SM), and mature (MM) stages were investigated. The effect of the diameter of the ultrasonic probe in the IM stage was also evaluated. The TPC and antioxidant activity in IM fruit extracts by UAE increased up to 11.01 and 23.82 times, respectively, compared to the maceration method. The main phenolic compounds in the PE of IM fruit identified by UPLC-DAD-ESI-MS/MS were quantified as caffeic acid, rutin, and rosmarinic acid, distributed as 45.82, 41.45, and 12.72%, respectively. The PE extracts of IM fruit obtained with the 3 mm diameter probe had 1.27, 2.44, and 1.37 times the TPC (19.93 ± 0.28 mg GAE (Gallic equivalents) g−1 dw), TFC (34.85 ± 4.99 mg RE (Rutin equivalents) g−1 dw), and antioxidant activity (122.09 ± 17.09 µTE (Trolox equivalents) g−1 (DPPH)), respectively, compared to those obtained with a 13 mm diameter probe. The results obtained suggest the use of the ciricote native fruit as a source of bioactive compounds, directly as fresh fruit or processed, thus helping to increase its production and consumption.

Ultrasound-assisted extraction of phenolic compounds in blackthorn (Prunus spinosa L.): characterization, antioxidant activity and optimization by response surface methodology

Ultrasound-assisted extraction of phenolic compounds in blackthorn (Prunus spinosa L.): characterization, antioxidant activity and optimization by response surface methodology

Establishment of a Sonotrode Ultrasound-Assisted Extraction of Phenolic Compounds from Apple Pomace

Apple pomace is the main by-product from apple processing in the juice industry and is considered a source of polyphenols with several health bioactivities. Thus, this research focuses on the establishment of the ultrasound-assisted extraction of total phenolic compounds, focusing on phloretin and phloridzin, with high antioxidant activity from apple pomace, using a sonotrode. We used a Box-Behnken design of 15 experiments with 3 independent factors (ethanol (%), time (min) and amplitude (%)). The responses evaluated were the sum of phenolic compounds, phloretin and phloridzin measured by HPLC-MS-ESI-TOF, and antioxidant activity measured by DPPH, ABTS and FRAP. The validity of the model was confirmed by ANOVA. Further, it was carried out using a comparison between different apple pomaces with or without seeds extracted by the optimal conditions. Phloretin and phloridzin accounted for 7 to 32% of the total phenolic compounds in the apple pomaces. Among all the apple pomace analyzed, that of the variety Gala had the highest phenolic content and antioxidant activity. The presence of the cyanogenic compound amygdalin was detected in apple pomaces that contained seeds accompanied with a higher content of phloretin and phloridzin but a lower content of flavan-3-ols.

Effect of solvent mixtures on the ultrasound-assisted extraction of compounds from pineapple by-product

Extraction of compounds from pineapple by-products can be affected by operational conditions and solvents. This study aimed to (i) carry out the ultrasound-assisted extraction of phenolic compounds from pineapple peels using different types of solvents and operating conditions and (ii) characterize the extracts obtained. The solvents with the highest efficiency in extracting total phenolic compounds (TPC), namely water, ethanol, and acid solution (1 mol L−1 HCl), were tested in different proportions using a simplex-centroid mixture design. The effects of time (5–45 min), temperature (30–60 °C), and ultrasonic power (0–100 W) were also evaluated. Extracts were assessed for antioxidant potential, phenolic profile, and sugar composition. TPC contents ranged from 219.75 to 405.06 mg GAE 100 g−1, with the highest value obtained in the mixture of ethanol (0.50) and acid solution (0.50). The extract with the highest TPC content and antioxidant activity was obtained at 60 °C, 50 W of ultrasonic power and 30 min. The extract obtained under these conditions contained fructose (7.17 g 100 g−1) and glucose (8.29 g 100 g−1) as major soluble sugars and caffeic acid (217.65 mg 100 g−1) as the major phenolic acid. Therefore, the extraction of compounds under the conditions studied is an alternative to the valorization of pineapple waste.

Hyphenated Extraction of Valuable Compounds from Aesculus carnea: Ultrasound Extraction with Pulsed Electric Field Pretreatment

Wood-related procedures, such as lumberjacking and pruning, inevitably result in big piles of leaves, which are considered a major by-product. Extracting valuable compounds from natural by-products is an ongoing trend. In this work, the use of Pulsed Electric Field (PEF) was evaluated as a pretreatment step, prior to the ultrasound-assisted extraction of phenolic compounds from Aesculus carnea leaves. In addition, various solvent systems were examined, as well as the time of pretreatment with PEF. According to the results, up to 33% more phenolic compounds can be extracted, under optimum conditions (30% ethanol in water as solvent and PEF pretreatment for 30 min, compared to the same solvent, without PEF). Moreover, PEF treatment time was not (i.e., 30 and 60 min) and no differences were recorded, suggesting that a lower treatment time can yield the same extraction of phenolic compounds. As such, the use of PEF is highly recommended in combination with ultrasound extraction, to maximize the yield of phenolic compounds extracted from the leaves of Aesculus carnea.

Ultrasound-Assisted Extraction of Phenolic Compounds from Adenaria floribunda Stem: Economic Assessment.

Adenaria floribunda is a native species found in tropical regions of South America used as a traditional medicine. Ultrasound-assisted extraction (UAE) is an extraction process known to increase the extraction yield, reduce extraction times, and use low temperatures. This study aims to obtain water-based extracts from A. floribunda stems using UAE, hot water extraction (HWE), and Soxhlet extraction and perform an economic analysis. The global extraction yield (GEY) and total phenolic compounds (TPC) of extracts ranged from 5.24% to 10.48% and from 1.9 ± 0.44 mg GAE g−1 DW to 6.38 ± 0.28 mg GAE g−1, respectively. Gallic acid, catechin, and ferulic acid were identified in the extract using HPLC-UV. Results indicate that Soxhlet extraction has the best performance regarding GEY and TPC. However, after performing an economic assessment, the cost of manufacturing (COM) of Soxhlet extraction (US$ 5.8 flask−1) was higher than the UAE (US$ 3.86 flask−1) and HWE (US$ 3.92 flask−1). The sensitivity results showed that obtaining extracts from A. floribunda by UAE and HWE is economically feasible when the selling price is above US$ 4 flask−1. Soxhlet extraction is a feasible technique when the selling price is above US$ 7 flask−1.