Ultrasound Extraction Research Articles

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.

Novel amide- and imide-co-polymers modified with sulfathiazole as efficient chelator for selective extraction, pre-concentration and determination of trace inorganic antimony (as Sb(III)) from edible vegetable oils by ultrasound assisted-cloud point extraction coupled to micro-volume UV-spectrophotometry

The study described the synthesis, characterization, and application of newly prepared sulfathiazole-modified amide/imide co-polymers for the extraction of trace Sb(III) from edible vegetable oils. The method was based on the pH-dependent complexation between Sb(III) and chelators as a result of charge transfer via tautomerization in presence of the mixed ionic surfactants in 5%(v/v) 2-propanol, 1:1, v/v) at pH 2.0 and 8.0, respectively for amide and imide copolymers and then selectively ultrasound assisted-cloud point extraction of the Sb(III)-complexes into the micellar phase of extractant. The separated micellar phase by centrifugation was diluted to 0.4 mL with tetrahydrofuran, and detected at 269 nm by micro-volume UV-spectrophotometry. The parameters affecting extraction efficiency were optimized. The optimal extraction conditions were found to be: 0.6/0.8 mmol L−1 of McIlvaine buffer, 30 µmol L−1 of the mixed-ionic surfactant mixture, 120 µmol L−1 KCl, 0.1/0.06% (v/v) of the nonionic surfactant and (0.4/0.2)× 10−3%(w/v) of sulfathiazole-modified amide/imide copolymers at pH 2.0 and 8.0 for 7 min at 40 °C in an ultrasonic bath (40 kHz, 300 W). From preconcentration of 20-mL sample, the good linear relationships (r2 ≥0.995) between absorbance and Sb(III) concentration were obtained from calibration curves prepared in solvent in range of 1–40 and 1–62.5 µg L−1 with the method detection limits of 0.30/0.47 and 0.51/0.51 µg L−1 at 269 nm by spectrophotometer after 50-fold pre-concentration. The accuracy was statistically verified by analysis of a non-certified sample with and without spiking where the precision and relative recoveries are within 5–12% and 83–92%, respectively. Also, the matrix effect was evaluated by triplicate measurements of 25 µg L−1 Sb(III) (n: 3) under optimal conditions. The method was successfully applied into the analysis of total iSb levels of edible vegetable oils. The results shown that the STZ-modified amide/imide co-polymers were efficient selective chelators even in presence of 50-fold excess Sb(V), and exhibited great potential as alternative binding chelators for the extraction of Sb(III) from edible vegetable oils.

Antioxidant Extracts of Nettle (Urtica dioica) Leaves: Evaluation of Extraction Techniques and Solvents.

Nettle (Urtica dioica) is a great source of bioactive compounds. The objective of this study was to evaluate the extraction techniques (ultrasound, without stirring, and stirring), solvents (methanol, water, and ethanol), and extraction times (1–4 h) to maximize antioxidant capacity of the Urtica dioica extracts. In the case of total phenolic content (TPC) and ABTS•+ (2,2-azino-bis(3-etilbenzotiazolin)-6-sulfonic acid) free radical scavenging values, ultrasound extraction was the most efficient method, while the best results of DPPH• (1,1-diphenyl-2-picrylhydrazyl) assay in nettle extracts (91.08%) were obtained using stirring extraction, water as solvent, and 3 h of extraction time. Based on the obtained mathematical models, the optimization revealed that the best extraction conditions were ultrasound treatment with water as solvent and an extraction time of 3.15 h, obtaining values of 21.9 mg eq gallic acid/g dried nettle for TPC, 71.8% for %ABTS•+ and 86.6% for %DPPH•. This work proves that aqueous extract of nettle leaves through the ultrasound technique is an important source of natural antioxidants and can be considered a potential alternative to synthetic antioxidants.

Effect of ultrasound assisted extraction of dietary fiber from pineapple peel and its application with anthocyanin rich black rice

The present study was focused primarily on the optimized extraction of dietary fiber (DF) from pineapple peel (PP) waste using alkaline and combined alkaline ultrasound methods and it was used with antioxidant rich black rice to prepare cookies with tailored physicochemical properties. The extraction of alkaline ultrasound extracted DF (AUEDF) was optimized using response surface methodology (RSM) conducted with central composite design (CCD). The optimum processing conditions for the AUEDF extraction method was solvent: solute (26.15 ml/g), ultrasound amplitude (34.32%) and sonication time (29.91 min), which gave the highest yield of DF (71.88%). Further, AUEDF yielded higher total DF content with well aligned and uniform fibrous structure, better thermal stability, crystallinity, water holding capacity, and oil holding capacity as compared to alkaline extracted dietary fiber (AEDF). The cookies were prepared by substituting wheat flour with extracted DF and black rice powder in flour formulation. The characteristics properties of the cookies in terms of texture, color, and sensory attributes were evaluated. The hardness and lightness of cookies were found to decrease with an increased concentration of black rice powder. Fuzzy logic was used for sensory evaluation, in which the cookie containing 30% black rice powder was found as the best sample. The quality attributes of cookies such as taste, and texture can be modified by the adopted strategy, which, are considered as important attributes for consumer acceptance followed by appearance and flavor. The results of the present investigation evinced that DF of pineapple waste utilization can be an excellent source for preparation of cookies with black rice. Novelty impact statement Dietary fibre (DF) from “Kew” variety pineapple peel was extracted via alkaline-ultrasound and alkaline extraction methods and comparison revealed that the DF extracted from the former evinced uniform fibrous structure, better thermal stability, crystallinity, and other functional properties over the latter extraction method. Cookies were developed using DF and antioxidant-rich black rice in the wheat formulation and the texture (hardness) and color of cookies decreased with increased black rice powder contents. Fuzzy logic was used to evaluate the preferred sensory properties of cookies and fortified cookie containing 30% black rice and 6% DF was selected as the best sample.

Extraction, amino acid estimation, and characterization of bioactive constituents from peanut shell through eco-innovative techniques for food application

ABSTRACT Agro-industrial waste has proved a huge problem owing to its disposal and impact on the environment. The eco-innovative technologies are applied to utilize waste as a resource. The mandate of the current investigation was to extract and characterize the bioactive molecules with special reference to luteolin from peanut shells through different innovative extraction techniques. This study was divided into two modules, in first the extraction of polyphenols was done through conventional and ultrasonic-assisted extraction (USE) by utilizing different solvents (ethanol 80%, methanol 80%, and water) and time intervals (5, 10 and 15 min for ultrasound and 30,60 & 90 min for conventional extraction technique) alongside HPLC and amino-acid characterization of a peanut shell. The results indicated that ultrasound proved significantly (p < .05) more effective as compared to conventional extraction and among solvent ethanol performed better as compared to methanol and water. Likewise, the time at 10 min also exhibited a significant effect on Peanut shell polyphenyl yield. The resultant highest value for TPC, DPPH, ABTS, FRAP, and β-carotene in ethanol of USE at 10 min was 3.79 ± 0.1 g GAE/100 g PS, 5.05 ± 0.1, 2.13 ± 0.03, 2.97 ± 0.03 and 5.33 ± 0.04 g TE/100 g PS, respectively. The resultant moieties exhibited high Luteolin contents after HPLC characterization and ranged from 1187 mg/g in conventional and 1409 mg/g in Ultrasound extraction. Likewise, the shell exhibited a promising amount of essential and non-essential amino acids. Conclusively, the peanut shell can be valorized due to its rich phytochemicals with special reference to luteolin.

Definitive screening design and I-optimal design for optimization of ultrasound-assisted extraction of phenolic content and antioxidant capacity from Salviaofficinalis L. leaves

A definitive screening design and an I-optimal design were carried out for the screening and optimization of ultrasound's extraction conditions of total phenolic compounds (TPC) and antioxidant capacities (TEAC and TAC) from S. officinalis L. leaves. The optimal conditions for maximum TPC, TEAC, and TAC were 52% ethanol-water, 60 °C temperature, 30 mL g−1 solvent to solid ratio, and 10 min of extraction time. The optimal extract showed higher TPC, TEAC, and TAC with 31.84 ± 0.248 mgGAE/gdw, 237.95 ± 0.771 μmolTE/gdw, and 38.928 ± 0.548 mgAAE/gdw respectively. Furthermore, the optimal extract obtained exhibited a higher scavenging activity against DPPH•, NO• free radicals, and β-carotene/linoleic acid bleaching activity with IC50 of 0.276 ± 0.001 mg/mL, and 0.069 ± 0.0005 mg/mL, and 0.159 ± 0.008 mg/mL respectively. The reducing power of the optimal extract at 0.3 mg/mL of lyophilized powder was approximately 2 mmol Fe+2 equivalent/g. Thus, S. officinalis L. leaves are expected to be an excellent source for pharmaceutical and cosmetic industries for developing potential drugs.

Carotenoid-Producing Yeasts: Selection of the Best-Performing Strain and the Total Carotenoid Extraction Procedure

Yeasts are considered an extraordinary alternative source of natural carotenoids and pigmented terpenoids with multiple applications. Production of carotenoids by yeast fermentation technology has many benefits; it is cost-effective, easily scalable, and safe. The aim of this research is the isolation of yeasts from natural resources and selection of the most potent bioagent for carotenoid production. Additionally, an upgraded carotenoid extraction protocol we established, which implies the testing of four methods for cell lysis (hydrochloric acid treatment, ultrasound treatment, milling treatment, and osmotic pressure treatment), three extraction methods (conventional extraction, ultrasound extraction, and conventional + ultrasound extraction), and three extraction solvents (acetone, isopropanol/methanol (50:50), and ethanol). For the first time, the obtained results were further modeled by an artificial neural network (ANN). Based on the obtained maximal carotenoid yield (253.74 ± 9.74 mg/100 g d.w) for the best-performing Rhodotorula mucilaginosa, the optimized extraction procedure involving milling treatment (for cell lysis) and conventional extraction with acetone (for carotenoid extraction) convincingly stood out compared to the other 35 tested protocols. Therefore, the selected carotenoid extraction protocol was verified with respect to its universality for all other yeast isolates, demonstrating its simplicity and effectiveness.

From Pomegranate Byproducts Waste to Worth: A Review of Extraction Techniques and Potential Applications for Their Revalorization

The food industry is quite interested in the use of (techno)-functional bioactive compounds from byproducts to develop ‘clean label’ foods in a circular economy. The aim of this review is to evaluate the state of the knowledge and scientific evidence on the use of green extraction technologies (ultrasound-, microwave-, and enzymatic-assisted) of bioactive compounds from pomegranate peel byproducts, and their potential application via the supplementation/fortification of vegetal matrixes to improve their quality, functional properties, and safety. Most studies are mainly focused on ultrasound extraction, which has been widely developed compared to microwave or enzymatic extractions, which should be studied in depth, including their combinations. After extraction, pomegranate peel byproducts (in the form of powders, liquid extracts, and/or encapsulated, among others) have been incorporated into several food matrixes, as a good tool to preserve ‘clean label’ foods without altering their composition and improving their functional properties. Future studies must clearly evaluate the energy efficiency/consumption, the cost, and the environmental impact leading to the sustainable extraction of the key bio-compounds. Moreover, predictive models are needed to optimize the phytochemical extraction and to help in decision-making along the supply chain.

Ultrasound and supercritical fluid extraction of phytochemicals from purple tamarillo: Optimization, comparison, kinetics, and thermodynamics studies

The parameters for extraction of phenolic compounds and anthocyanins in purple tamarillo using supercritical fluid (SCFE) and ultrasound-assisted extraction (UAE) techniques were optimized. Optimizations of extraction techniques were done using Box-Behnken design in response surface methodology. Based on the total phenolic content, the experimental range for the independent variables in SCFE was set at 30 to 60 min, 40–60 °C, and 150 to 180 bars of pressure (TPC). Similarly, for UAE, the selected independent variables were 10–30 min time, 40–60 °C temperature and 20–60% amplitude. The optimized conditions for SCFE were determined to be 49.42 min, 49.28 °C and 176.63 bar pressure, and at the optimized parameters, the TPC was 16.12 mg GAE/g and anthocyanins was 0.62 mg C3G/g in the extract. The optimized parameters for UAE were 19.14 min, 51.53 °C, and 50.53% amplitude, which yielded 21.06 mg GAE/g TPC and 0.71 mg C3G/g anthocyanins. Four phenolic acids (gallic acid, chlorogenic acid, caffeic acid, and p-coumaric acid) and three anthocyanins (delphinidin-3-O-rutinoside, cyanidin-3-O-rutinoside, and pelargonidin-3-O-rutinoside) were identified by HPLC in both the extracts. However, higher concentration of phenolic acids and anthocyanins were extracted by UAE as compared to SCFE. SEM morphology of sample matrix showed extensive disintegration after UAE process. The optimized extract can be used in the food industry as a natural colorant in place of synthetic pigments that are bad for customers' health and wellbeing. The extract also can act as a source of potential antioxidants and can be used in the development of new functional foods.

Mutivariate optimization strategy for the sonication-based extraction of Nardostachys jatamansi roots and analysis for chemical composition, anti-oxidant and acetylcholinesterase inhibitory potential

Extracts from medicinal plants are generally obtained by conventional methods like percolation and maceration. Owing to limitations of traditional methods and to meet the rising demand of extracts, the development of new green approaches is need of hour. In the present research, we have developed an ultrasound-assisted extraction (UAE) method for the Nardostachys jatamansi (NJ) D. Don, DC roots and optimized the extraction parameters for possible improved extract yield. A multivariate optimization strategy using the Centre Composite Design coupled with response surface methodology was applied. A numerical optimization approach accurately predicted the extraction conditions (sonication time ∼ 20 min, ethanol ∼ 70 % and a liquid/solid ratio of about 21:1). Scanning electron microscopy of the plant samples after UAE also indicated the cavitation effect due to sound waves. GC–MS analysis of the optimized ultrasound extract (OUNJ) confirmed improvement in the concentration of various secondary metabolites like jatamansone (91.8 % increase), spirojatamol (42.3 % increase), globulol (130.4 % increase), sitosterol (84.6 % increase) as compared to the soxhlet extract (SXNJ). Different anti-oxidant parameters (DPPH, Glutathione, Catalase SOD and NO) were also significantly altered (p < 0.05) in the optimized extracts. The IC50 to inhibit acetylcholinesterase activity (AChE) in vitro and its concentration in brain homogenates were significantly (p < 0.05) improved by OUNJ extract as compared to the SXNJ ones. To conclude, we can say that established optimized conditions for UAE of N. jatamansi roots not only reduce the extraction time but also improved the pharmacological potential of the extracts.

Optimization of a Green Extraction of Polyphenols from Sweet Cherry (Prunus avium L.) Pulp

This work focused on the optimization of the ultrasound (US) extraction of polyphenols from sweet cherry pulp by monitoring cyanidin-3O-rutinoside, quercetin-3O-rutinoside, and trans-3-O-coumaroylquinic acid, representing the main anthocyanin, flavonol, and hydroxycinnamate, respectively, identified in the extracts through chromatographic analyses (HPLC-DAD), as output variables. The optimization was performed following a two-level central composite design and the influence of the selected independent variables (i.e., extraction time and solid to solvent ratio) was checked through the response surface methodology. The maximum recovery of the phenolic compounds was obtained at 3 min and 0.25 g/mL in water/ethanol (1:1, v/v) at a set temperature (25 °C), sonication power (100 W), and sonication frequency (37 kHz). Subsequent validation experiments proved the effectiveness and reliability of the gathered mathematical models in defining the best ultrasound-assisted extraction conditions.

Enhancement of bioactive compounds and oxidation stability of soybean oil by enrichment with tocols and γ‐oryzanol extracted from rice bran using ultrasound and ohmic heating

Soybean oil is beneficial from a nutritional viewpoint; however, the high concentration of polyunsaturated fatty acid presents a high risk of oxidation. This study incorporated α- and γ-tocopherols and γ-oryzanol as natural antioxidants from rice bran into soybean oil to improve oxidation stability of the oil using ohmic heating-assisted ultrasound extraction. Moisturized bran (30% wet basis) was pretreated using an ohmic heater at 100 and 200 V/cm before ultrasound extraction using soybean oil as a green solvent. Raw and steamed rice bran extracted by ultrasound without ohmic heating were used as controls. Enriched soybean oil obtained from ohmic heating pretreatment gave the highest concentration of α- and γ-tocopherols, γ-oryzanol, and antioxidant activities with low concentrations of free fatty acids, thiobarbituric acid, and peroxide values. Results suggested that ohmic heating-assisted ultrasound extraction showed potential to enrich soybean oil with bioactive compounds. Practical applications Soybean oil can be enriched with tocols and γ-oryzanol from rice bran to increase oil quality and oxidative stability. Ohmic heating was applied to assist ultrasound extraction of tocols and γ-oryzanol from rice bran. Extraction of edible vegetable oils using ohmic heating-assisted ultrasound is an alternative green process to improve oil quality and produce functional vegetable oils enriched with value-added compounds.

Development and Evaluation of an Antimicrobial Formulation Containing Rosmarinus officinalis.

Rosmarinus officinalis belongs to the Lamiaceae family, and its constituents show antioxidant, anti-inflammatory, antidepressant, antinociceptive, and antibacterial properties. The aim of this study was to develop a topical formulation with R. officinalis extract that had antimicrobial and antioxidant activity. Maceration, infusion, Soxhlet, and ultrasound were used to produce rosemary extracts, which were submitted to antioxidant, compound quantification, cell viability, and antimicrobial assays. Infusion and Soxhlet showed better results in the DPPH assay. During compound quantification, infusion showed promising metabolite extraction in phenolic compounds and tannins, although maceration was able to extract more flavonoids. The infusion and ultrasound extracts affected more strains of skin bacteria in the disk diffusion assays. In the minimum inhibitory concentration assay, the infusion extract showed results against S. aureus, S. oralis, and P. aeruginosa, while ultrasound showed effects against those three bacteria and E. coli. The infusion extract was chosen to be incorporated into a green emulsion. The infusion extract promoted lower spreadability and appropriated the texture, and the blank formulation showed high levels of acceptance among the volunteers. According to the results, the rosemary extract showed promising antioxidant and antimicrobial activity, and the developed formulations containing this extract were stable for over 90 days and had acceptable characteristics, suggesting its potential use as a phytocosmetic. This paper reports the first attempt to produce an oil-in-water emulsion using only natural excipients and rosemary extract, which is a promising novelty, as similar products cannot be found on the market or in the scientific literature.

Comparison of structural characteristics and bioactivity of Tricholoma mongolicum Imai polysaccharides from five extraction methods.

Tricholoma mongolicum Imai is an edible fungus rich in various health-promoting compounds, such as polysaccharides, polypeptides, polyunsaturated fatty acids, etc., and among them, polysaccharides have gotten more attention in recent research trends. This study explored the extraction of polysaccharides from T. mongolicum Imai by five extraction methods, including hot water extraction, ultrasound extraction, enzyme-assisted extraction, 0.1 M HCL extraction, and 0.1 M NaOH extraction. The effects of these extraction methods on the yield, chemical structure, apparent morphology, and the antioxidant activities of Tricholoma mongolicum Imai polysaccharides (TMIPs) were investigated in this study. The data showed that 0.1 M NaOH extraction produced the highest extraction yield compared to the other extraction methods. The results of high-performance gel permeation chromatography (HPGPC) and scanning electron microscopy (SEM) showed that different extraction methods had significant effects on the molecular weight and morphology of TMIPs. The results of Fourier transform infrared (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis showed that the extraction methods had no significant difference in functional groups, crystal structure, and thermal stability of TMIPs. The antioxidant activity of TMIPs extracted by ultrasound extraction was more prominent among the five polysaccharides, which might be related to a large number of low-molecular-weight components in molecular weight distribution.

Determination of Carcinogenic Primary Aromatic Amines Contained as Impurities in Synthetic Organic Colorants.

Several primary aromatic amines (PAAs) have been designated carcinogenic or suspected of carcinogenicity. Several kinds of PAAs may occur either via the reduction of azo compounds or as impurities in azo colorants or other agents. An analytical method was developed and applied to determine whether certain PAAs are present as impurities in synthetic organic colorants. Target chemicals were analyzed by the ultrasound extraction of the synthetic organic colorant with a hydrochloric acid solution containing 20% methanol, followed by conversion from an acidic to alkaline solution, and then extraction using a diatomaceous earth column. We analyzed certain PAAs in 38 synthetic organic colorants, resulting in the detection of 2,4-dimethylaniline in four samples at 1.2 to 19 μg/g, o-toluidine in three samples at 1.0 to 3.4 μg/g, p-phenylazoaniline in two samples at 74 to 305 μg/g, and, in one sample each, 2,4,5-trimethylaniline (13 μg/g), 5-nitro-o-toluidine (12 μg/g), and 2-methyl-4-(2-tolylazo)aniline (13 μg/g). Nearly all PAAs were determined to be starting materials for colorant synthesis, although p-phenylazoaniline in Yellow No. 407 was apparently a byproduct formed during synthesis. For Red No. 225, in which high concentrations of p-phenylazoaniline were detected, additional samples were purchased from five companies, and p-phenylazoaniline was detected at concentrations of 88 to 370 μg/g in all samples. A method to analyze certain PAAs contained as impurities in synthetic organic colorants was developed, and the actual status of them in colorants was clarified. The analytical method developed in this study for the determination of certain PAAs contained as impurities in synthetic organic colorants may be used to improve the safety of colorants.

Effect of microwave and enzymatic pretreatment and type of solvent on kinetics of ultrasound assisted extraction of bioactive compounds from ripe papaya peel

AbstractThe study was aimed to investigate the effect of pretreatment by microwave and enzyme and type of solvent on kinetics of ultrasound‐assisted extraction (UAE) of bioactive compounds and antioxidant activity from papaya peels. The enzyme used was viscozyme and the solvents used were water, ethanol, and their combination (1:1). The effect of combination of pretreatments was also studied. The data from the experiments were fitted to second order kinetic model and Langmuir model. The second order rate constant (k) varied from 0.0005 to 0.0134 for total phenolic content (TPC), 0.0016–0.0080 for total flavonoid content, and 0.0004–0.0228 for antioxidant activity (2,2‐diphenyl‐1‐picrylhydrazyl‐radical scavenging activity). The comparative kinetic assessment illustrated that the progression of the extraction for TPC was higher in enzyme‐water (E‐W) treatment (98.91 mg Gallic acid equivalent (GAE)/100 g), followed by microwave‐enzyme water (ME‐W) treatment (93.98 mg GAE/100 g) while microwave‐water:ethanol (M‐WEt) treatment gave the lowest yield (42.56 mg GAE/100 g), respectively. The present study also investigated influences of ultrasonication on extraction kinetics and their yield. Ultrasound was clearly influencing the yield (over 72.95% increase in yield of polyphenols). Antioxidant activity of the extracts confirmed that the UAE extraction is suitable for preparing antioxidant‐rich plant extracts. Ultrasound and pretreatment before extraction could provide many advantages like increased yield and quality, energy efficiency, faster extraction, and low solvent consumption.Practical ApplicationsPapaya peels are waste products generated during processing of papaya and are valuable sources of polyphenols and natural antioxidants such as caffeic acid, rutin, ferulic acid, p‐coumaric acid, and many more bioactive compounds that have significant biological activity. These bioactive compounds of papaya peel can be extracted and utilized in food and pharmaceutical industry for development of functional food or nutraceuticals. Ultrasound extraction is regarded as a green technology as it is environment friendly and energy‐efficient process. When ultrasound technology is combined with microwave or enzymatic treatment, the efficiency of such process may be further improved. The present study is therefore useful as it can provide a solution for utilization of papaya peel for extraction of valuable compounds using green technology.

Optimization of ultrasonic-assisted extraction of phenolic compounds from pomegranate and orange peels and their antioxidant activity in a functional drink

This study aimed to optimize the ultrasound extraction conditions of phenolic compounds from pomegranate (PPE) and orange peels (OPE) as agricultural wastes and use the optimized extracts to enrich a functional drink. The statistical analysis results demonstrated that the quadratic model used had high R2 (>0.89) and good predictability of experimented results. In optimizing the extraction of PPE and OPE, the effect of three factors of extraction time (X1:10–40 min), temperature (X2: 40–70 °C), and solid to a solvent ratio (X3: 1:20–1:40 g/mL) on two responses of total phenol content (TPC) and antioxidant activity were investigated. The highest TPC (2.70 and 1.86 mg GAE/g) and antioxidant activity (72.11 and 54.27%) of PPE and OPE were obtained in the X1: 40 min, X2: 70 °C, and X3: 1:40 g/mL. No significant difference was observed between the predicted and experimental values. The results of drink tests indicated that adding PPE and OPE and increasing their levels from 10% to 15% v/v in the drinks significantly enhanced the samples' bioactive compounds content and antioxidant activity (p < 0.05). The content of vitamin C (212.37 mg/100 mL) and flavonoids (83.44 mg QE/100 mL) in the drink containing 15% OPE was higher than in other samples, while the sample containing 15% PPE had the highest TPC (158.88 mg GAE/100 mL). There was a positive relationship between the level of extracts and the antioxidant activity of the drinks. During 60-days of cold storage, the content of bioactive compounds and antioxidant activity of drink samples gradually decreased (p < 0.05).

Effects of incorporation of Chavir ultrasound and maceration extracts on the antioxidant activity and oxidative stability of ordinary virgin olive oil: identification of volatile organic compounds

Effects of incorporation of Chavir ultrasound and maceration extracts on the antioxidant activity and oxidative stability of ordinary virgin olive oil: identification of volatile organic compounds

Ultrasound-Assisted Extraction of High-Value Fractions from Fruit Industrial Processing Waste.

This work deals with the valorization of fruit industrial processing waste pretreated with two dehydration methods, air oven and lyophilization. Ultrasound-assisted extraction using a sonication probe was selected to recover the high-value fractions. A battery of experiments following a Box–Behnken design was planned to evaluate the effect of the ultrasound amplitude, extraction duration, and temperature on the yield, protein content, phenolic content, and antiradical capacity of the soluble extracts. Operating at a fixed frequency (24 kHz) and solid:water ratio (1:15), the models predicted (significance degree >95%) the maximum extraction conditions of 69.7% amplitude, 53.43 °C, and 12 min for conventionally dehydrated fruit waste. Under these processing conditions, 52.6% extraction yield was achieved, with a protein content of 0.42 mg/g, total phenolic content of 116.42 mg GAE/g, and antioxidant capacity of 44.95 mg Trolox/g. Similar yields (53.95%) and a notably higher protein content (0.69 mg/g), total phenolic content (135.32 mg GAE/g), and antioxidant capacity (49.52 mg Trolox/g) were identified for lyophilized fruit waste. This treatment required a longer dehydration pretreatment duration (double), higher ultrasound amplitude (80%), and higher extraction temperature (70 °C), but shorter extraction time (4 min). These outcomes highlighted the important impact of the dehydration method on the valorization of the tested waste, with conventional drying saving costs, but the lyophilization procedure enhancing the bioactive features of the waste.

PH-controlled charge transfer sensitive 2-aminobenzimidazole modified poly(styrene-co-maleic anhydride) copolymer for selective extraction, pre-concentration and determination of trace Hg2+ and CH3Hg+ in vinegar by combination of ultrasound assisted-cloud point extraction with UV–VIS spectrophotometry

In this study, a separation/pre-concentration procedure, ultrasound assisted-cloud point extraction with modified 2-aminobenzimidazole (2-ABzI), was developed for the extraction of trace Hg2+ and CH3Hg+ and from vinegar samples- modified copolymer coupled with Hg-binding chelator, 2-ABzI. The imidic copolymer was characterized, and used for detection of the enriched Hg species by spectrophotometer at 332 nm. The method is based on their pH-induced charge transfer sensitive complexation with copolymer matrix via 2-AmBzI moiety at pH 6.0 and 4.5, and their extraction into the mixed micellar phase of the mixed non-ionic/ionic surfactants as extractant/sensitivity enhancer. The variables influencing the extraction efficiency were optimized. From pre-concentration of 25-mL sample, with a changing calibration sensitivity and pre-concentration factor of 62.5, a good rectilinear relationship between absorbance and concentrations of Hg species in ranges of 1–15, 15–150 µg L−1 was obtained. The detection limits are 0.30 and 0.31 µg L−1, respectively. Its precision/accuracy were in range of 3.1–7.6 % and 90.5–96 % after spiking (n: 5, for measurements of 5, 25 and 100 µg L−1 in same day and three consecutive days). The matrix effect was also studied (n: 3, 100 µg L−1). The method is simple, cost-effective, fast, accurate, safe, highly stable and selective, which has successfully been applied to the speciation of mercury in vinegar.