Ultrasound-assisted Extraction Extraction Research Articles

Optimization of ultrasound-assisted extraction using box-Behnken design, method validation, and analysis of phytochemicals from drying treatments in the application of Etlingera elatior inflorescence

Background: Etlingera elatior inflorescence, a potential source for herbal tea, undergoes a drying process that could enhance the active ingredients and health benefits. This study introduces the use of ultrasound-assisted extraction (UAE) to improve conventional extraction and increase the yield of phytochemicals, thereby presenting a novel approach to functional foods and nutrition. Objective: This study aims to optimize the UAE method using the Box-Behnken Design (BBD), a statistical experimental design widely used in the field of functional foods and nutrition. The determination of phytochemicals was validated using the optimized UAE. Chlorogenic acid from the extract was analyzed using HPLC-DAD and compared with that from Indonesia. According to the development of herbal tea, the phytochemical contents and inhibition of DPPH scavenging antioxidant activity were examined for the three drying treatments compared to freeze-drying. Methods: Box-Behnken Design (BBD) was used to optimize the condition of UAE with three variables: solvent concentrations (70%, 85%, 100%), solid-to-solvent ratios (1:20, 1:15, 1:10), and temperatures (30°C, 50°C, 70°C). The TPCs and TFCs of the ethanol extract were analyzed as observed responses. Repeatability precision (%CV) and recovery were validated for the optimized UAE. HPLC-DAD analyzed the chlorogenic acid of the extract and compared it to the Thai E. elatior extract and Indonesia. In applying E. elatior tea, phytochemical contents, and DPPH∙, scavenging antioxidant activity was examined for three drying treatments and compared to the freeze-drying treatment. Results: The suggested condition of optimized UAE extraction was 70% ethanol, 50°C, and a 1:20 solid-to-solvent ratio. %Repeatability precision of TPCs and TFCs for the extract was significantly <5%, and %recovery >90%. Freeze-drying and cabinet-drying treatments had significantly higher TPCs than others. Especially in freeze-drying treatment, the TFCs of the extract from Indonesia were significantly greater than those in Thailand (p<0.05). For DPPH∙ antioxidant activity, all treatments except freeze-drying of the extracts from Indonesia had higher inhibition of DPPH∙ antioxidant activity than those from Thailand. Conclusion: The optimized UAE extraction method was validated with high precision and accuracy. All drying treatments influenced the phytochemical contents and Inhibition of DPPH antioxidant activity in the inflorescences of both Thailand and Indonesia. Keywords: Box-Behnken Design, drying treatment, tea, method validation, phenolic.

Optimization of ultrasound-assisted extraction conditions for active components and anti-alzheimer activities from mentha cordifolia

Mentha cordifolia .(Lamiaceae) or Mint, is distributed all over the world. Essential oils found are menthol, menthone, 1,8-cineole, pinene, myrcene, and borneol. M. cordifolia. most popular herb, is widely used in cooking, cosmetics, complementary therapy, and pharmaceuticals for anti-carcinogen, gastro protective, antimicrobial, and antivirus purposes. The manufactory extracted essential oil method used steam distillation and hydro-distillation, which decomposed the components. The aim of this work was to study the innovative technologies of chemical constituents’ extraction by ultrasound-assisted extraction (UAE) that include high yields, short-extraction times, and energy savings. The extraction of Mentha cordifolia was carried out at 20 KHz ultrasonic frequencies. Sonicated times were 1.5 h. Antioxidant studies of essential oils by UAE extraction were 2, 2-diphenyl-1-1-picrylhydrazyl (DPPH), 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), and pharmacological activity was anti-Alzheimer (Ellman’s method). The UAE method used hexane, ethyl acetate, and ethanol as solvents and set the time to 1.0 h; in the second experiment, it set the time to 1.5h in the same system. Crude hexane (F1) extracted gave terpene and essential oils; crude ethyl acetate (F2) extracted gave flavonoids; and crude ethanol (F3) extracted gave phenolic compounds. The UAE method gave fractions F1, F2, and F3, which showed the DPPH activity was IC50 259, 229, and 74 mg/mL; ABTS radical scavenging was IC50 129, 103, and 127 mg/mL; and anti-acetylcholinesterase was IC50 128, 126, and 137mg/mL, respectively. The antioxidants tested were treated by applying multivariate statistical analysis.

Optimization of ultrasound-assisted extraction of glycyrrhizic acid and glabridin from Glycyrrhiza glabra L. using response surface methodology and development of a green analytical method

In this study, ultrasound assisted extraction (UAE) were used to investigate the extraction of glycyrrhizic acid (GA) and glabridin (GD) simultaneously from Glycyrrhiza glabra L. and a green HPLC analytical approach for determining GA and GD was developed. Extraction pocess were optimizing by Response surface methodology (RSM) utilizing Box-Behnken design (BBD). According to the consequences, the ideal extraction situations were: 64% (v/v) ethanol concentration, 22 mL/g liquid-solid ratio, 51 °C and 31 min. Under these conditions, the yields of GA and GD were 2.806 ± 0.107% and 0.252 ± 0.026%, respectively, and the actual experimental extraction values were fundamentally the same as the anticipated values. Meanwhile, the effects of UAE, maceration (MAC) and heat-reflux extraction (HRE) on yeild were assessed, and the UAE possessed highest yields. A green HPLC approach was created to analyze GA and GD with combinations of ethanol and a 0.1% (v/v) trifluoroacetic acid mobile phase (following the gradient elution method). The method validated based on the guidelines of the International Conference on Harmonization (ICH) and the result indicated the method was precise, stable, reliable and valuable, could be used to analyze GA and GD from Glycyrrhiza glabra L.

Comparative study of bioactive compound content and antioxidant activity in different extraction methods of Syzygium Polyanthum leaves

Link of Video Abstract: https://youtu.be/VtCPJX9TPg4 Background : Syzygium Polyanthum is classified among the 5,000 medicinal plant species documented in the Indonesian Medicinal Herb Index. It is utilised for a variety of purposes in traditional medicine and has potential health benefits. Extraction of medicinal plants is crucial to separate active plant materials or secondary metabolites. The aim of the study was to compare extracts of Syzygium Polyanthum Leaves using different methods: maceration and UAE in extracting flavonoids, phenolic compounds and antioxidant activity. Methods: the bioactive component content and antioxidant activity of Syzygium polyanthum leaves extracted using two different methods—maceration and ultrasound-assisted extraction (UAE)—are compared. 96% ethanol was employed as the extracting solvent in the maceration and UAE extraction processes for S. polyanthum.The bioactive substances in both extracts were determined using Liquid Chromatography-High Resolution Mass Spectrometry (LC-HRMS). Result: The amount of total phenolic, flavonoid, and IC50 in S. polyanthum leaves was evaluated between the maceration extraction method and UAE. Liquid chromatography-high Resolution Mass Spectrometry (LC-HRMS) analysis was utilized to detect the presence of bioactive compounds, then classified according to the PubChem database's taxonomy. There were comparable amounts of flavonoids in both extracts (60.194 mg QE/g and 60.074 mg QE/g). According to the DPPH assay, the total phenol for the extracts obtained by maceration and UAE was 94.63 ± 2.18 mg GAE/g and 122.87 ± 5.99 mg GAE/g extracts respectively, and the IC50 for the extracts obtained by maceration and UAE were 88.21 ± 1.38 μg/mL and 41.23 ± 6.11 μg/mL. Conclusion: The findings of the study indicated that the ultrasonic-assisted extraction (UAE) approach yielded significantly greater quantities of total phenolic and flavonoid compounds, as well as exhibited stronger antioxidant activity, when compared to the maceration extraction method. The utilisation of the UAE approach resulted in a significant rise in the antioxidant activity of S. polyanthum leaves.

The Extraction Process, Separation, and Identification of Curcuminoids from Turmeric Curcuma longa.

Turmeric Curcuma longa is a well-known spice with various health benefits, attributed primarily to curcumin. Soxhlet extraction, cold maceration, ultrasound-assisted extraction (UAE), and supercritical fluid extraction were performed, and the content of total phenols, proanthocyanidins, and antioxidants was analysed by UV/VIS spectrophotometry. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was employed to identify and quantify the curcumin content. Supercritical extracts had the highest total phenolic content (538.95 mg GA/100 g material), while the Soxhlet extracts had the highest content of proanthocyanidins (4.77 mg PAC/100 g of material). Extracts obtained by UAE and supercritical extraction have the highest antioxidant potential. Antioxidant activity measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH•) was 64.27% and 1750.32 mg Trolox per g dry weight by 2,2-azinobis(3-ethylbenzothiazoline 6 sulphonic acid) (ABTS+•) for the extract obtained by supercritical extraction. The UAE resulted in the highest amount of curcumin (1.91 mg curcumin/g material). A kinetic study showed that extraction yield in supercritical extracts decreased with increasing temperature and that the content of isolated curcumin was inversely proportional to solvent-to-feed ratio (S/F). The present study has confirmed that turmeric is an excellent source of antioxidants, such as curcumin, that play an important role in reducing cellular stress by neutralising free radicals.

Green Extraction of Antioxidant Fractions from Humulus lupulus Varieties and Microparticle Production via Spray-Drying.

The formulation of polymeric microparticles to encapsulate bioactive compounds from two hop varieties (Nugget and Perle) using sequential green extraction processes was performed. The technologies used were ultrasound-assisted extraction (UAE) and pressurized hot water (PHW) extraction. Liquid phases were analyzed for total phenolic content (~2%), antioxidant activity (IC50, DPPH: 3.68 (Nugget); 4.46 (Perle) g/L, TEAC (~4-5%), FRAP (~2-3%), and reducing power (~4%)), protein content (~1%), oligosaccharide content (~45%), and for structural features. The fractions obtained from UAE were selected to continue with the drying process, achieving the maximum yield at 120 °C (Perle) and 130 °C (Nugget) (~77%). Based on these results, the formulation of polymeric microparticles using mannitol as the carrier was performed with these fractions. The production yield (~65%), particle size distribution (Perle: 250-750 µm and Nugget: ~100 µm), and rheological features (30-70 mPa s at 0.1 s-1) were the parameters evaluated. The UAE extracts from hop samples processed using a sustainable aqueous treatment allowed the formulation of microparticles with a suitable yield, and morphological and viscosity properties adequate for potential food and non-food applications.

Optimization Conditions of Ultrasound-Assisted Extraction for Phenolic Compounds and Antioxidant Activity from Rubus alceifolius Poir Leaves.

Rubus alceifolius Poir (R.A. Poir) leaves are rich in phenolic compounds, offering many health benefits due to their incredible antioxidant potential. In this study, conditions for the ultrasound-assisted extraction (UAE) of phenolic compounds and antioxidant activity from R.A. Poir leaves were optimized using response surface methodology (RSM). This methodology assessed the effects of ultrasound power (X1: 100-500 W), extraction temperature (X2: 30-60°C), and extraction time (X3: 5-55 min). The optimized UAE conditions were then compared with conventional extraction methods (Soxhlet extraction: SE and maceration extraction: ME) for extracting total phenolics. A phenolic profile using GC-MS and antioxidant activity (ABTS) was also compared. According to the RSM, the best conditions for UAE to extract the highest total polyphenol content and ABTS radical scavenging activity were 320 W ultrasound power, 40°C extraction temperature, and 35.5 min sonication duration. Under these optimal conditions, the TPC and antioxidant activity reached 16.68 mg GAE/g dm and 21.9 mg TE/g, respectively, closely aligning with the predicted values. The UAE extraction technique proved to be more efficient in extracting phenolics and antioxidant capacity (ABTS (2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)) radical scavenging activity, and enzyme inhibition) compared to the conventional extraction methods (SE and ME). A GC-MS analysis identified 12 components, including 5 phenolics and 3 flavonoids, which likely contribute to the antioxidant activity. Consequently, the UAE method improved extraction efficiency within a shorter time frame, suggesting that UAE is a promising, efficient, and ecofriendly technology for extracting bioactive compounds from R.A. Poir leaves.

Phytochemical Screening of Ultrasonic Extracts of Salix Species and Molecular Docking Study of Salix-Derived Bioactive Compounds Targeting Pro-Inflammatory Cytokines.

Willow bark (Salix spp., Salicaceae) is a traditional analgesic and antirheumatic herbal medicine. The aim of this study was to evaluate and compare the phytochemical and antioxidant profiles of leaf and bark extracts of six species of the genus Salix obtained by ultrasound-assisted extraction (UAE) and to examine the inhibitory potential of target bioactive compounds against two inflammatory mediators, tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6), through in silico molecular docking. The total phenolic and flavonoid content of the extracts was estimated using spectrophotometric methods and the antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and hydroxyl radical (•OH) scavenging assays. Chemical profiling of extracts was carried out using high-performance liquid chromatography coupled with a diode array detector (HPLC-DAD). Principal component analysis (PCA) was performed to differentiate the sample extracts based on their phytochemical profiles and amounts of target bioactive compounds. Chemical composition varied among the analyzed willow species and also among the plant organs of the same species. The major bioactive compounds of the extracts were salicin, chlorogenic acid, rutin and epicatechin. The extracts exhibited significant DPPH● and ●OH scavenging activities. Results of molecular docking revealed that chlorogenic acid had the highest binding affinity toward TNF-α and IL-6. UAE extracts represent valuable sources of antioxidant and anti-inflammatory compounds.

A Comparative Study between Microwave Hydrodiffusion and Gravity (MHG) and Ultrasound-Assisted Extraction (UAE): Chemical and Biological Characterization of Polyphenol-Enriched Extracts from Aglianico Grape Pomace.

The wine industry produces large amounts of grape pomace (GP), a waste that needs to be disposed of properly. Bioactive compounds with high added value can be recovered from GP as an interesting strategy to reduce the environmental impact. Here, two different technologies were employed to recover polyphenol compounds from GP: microwave hydrodiffusion and gravity (MHG) and ultrasound-assisted extraction (UAE). The further purification of UAE and MHG extracts was carried out through solid-phase extraction (SPE) to obtain three fractions, F1, F2 and F3. ATR-FTIR analysis confirmed the presence of sugar and polysaccharide components in F1, as well as non-anthocyanin and anthocyanin compounds in F2 and F3, respectively. Also, the chemical profile was determined by HPLC-UV-DAD, identifying the presence of catechin in F2, and malvidin-3-O-glucoside chloride and cyanidin chloride derivative as the main anthocyanin compounds in F3. The fractions and their parental extracts were characterized for total phenolic content (TPC) and scavenger activity by in vitro assays. We found that F2-MHG and F3-MHG contained phenol contents 6.5 and 8.5 times higher than those of the parental non-fractionated extracts. Finally, F3-MHG (100 μg/mL, w/v) was shown to reduce the proliferation of HT-29 cells.

Application of Response Surface Methodology (RSM) for the Optimization of Ultrasound-Assisted Extraction (UAE) of Moringa oleifera: Extraction Yield, Content of Bioactive Compounds, and Biological Effects In Vitro.

This study optimized ultrasound-assisted extraction conditions to maximize the extraction yield, total flavonoid content (TFC), total phenolic content (TPC), and DPP IV enzyme inhibitory activity from Moringa oleifera. The four UAE factors, solvent ratio (A), solvent-solid ratio (B), extraction temperature (C), and extraction time (D), were optimized using response surface methodology (RSM). A Box-Behnken design was used for the experimental design. The optimal conditions were found to be a 50% v/v solvent ratio, a 30% v/w solvent-solid ratio, 35 °C extraction temperature, and 45 min extraction time. The experimental value of extraction yield (R1), TFC (R2), TPC (R3), and DPP IV enzyme inhibitory activity (R4) (87.99% w/w, 56.63 mg QE/g extract, 97.26 mg GAE/g extract, and 93.32% inhibition, respectively) agreed with those predicted by RSM models (88.10% w/w, 56.61 mg QE/g extract, 97.16 mg GAE/g extract, and93.38% inhibition, respectively), thus demonstrating the appropriateness of the model used and the ability of the RSM to optimize the extraction conditions. Excellent DPP IV enzyme inhibitory activity was exhibited by M. oleifera compared with the standard, sitagliptin. While the modeled equation fits the data, the t-test is not significant, suggesting that the experimental values agree with those predicted by the RSM-BBD.

Comparison of the effect of extraction methods on the waste cotton (Gossypium hirsutum L ) flowers: metabolic profile, bioactive components, antioxidant, and α-amylase inhibition.

Waste cotton flowers, as a by-product of cotton cultivation, are enriched with bioactive substances that render them a promising natural source of health-promoting benefits. In this study, ultrasound-assisted extraction (UAE), subcritical water extraction (SWE) and conventional extraction (CE) approaches were applied to extract bioactive compounds from waste cotton flowers, and metabolic profile, bioactive components, antioxidant, and α-amylase inhibition of different extractions were systematically analyzed and compared. It was observed that the UAE and CE extract had similar metabolic profiles compared with SWE. The flavonoids and amino acids and derivatives were more prone to be extracted by UAE and CE, while phenolic acids tended to accumulate in SWE extract. The UAE extract had the highest amounts of total polyphenols (214.07 mg GAE/g DW) and flavonoids (33.23 mg RT/g DW) as well as the strongest inhibition on oxidation (IC50 =10.80 μg/mL) and α-amylase activity (IC50 =0.62 mg/mL), indicating that chemical composition was closely related to biological activity. Additionally, microstructures and thermal behaviors of the extract were investigated and highlighted the ability of UAE. Overall, it can be concluded that UAE is an efficient, green, and economical extraction method to produce bioactive compounds from cotton flowers, and the UAE extracts could be used in food and medicine industries because of their high antioxidant and α-amylase inhibitory activity. This study provides scientific basis for the development and comprehensive utilization of cotton by products. This article is protected by copyright. All rights reserved.

The extraction effect of the skin of dragon fruit (Hylocereus polyrhizus) to its phenolic compounds and its antioxidants: A review

Dragon fruit contains various nutrients and functional values both in the flesh and skin. The skin of dragon fruit contains 30-35% water. It has lots of phenolic compounds and antioxidants, of which the higher amount of antioxidants are in the skin. These compounds are very easily damaged due to the extraction process especially if done incorrectly. This article is written to be a guide in selecting the extraction process in order to preserve the compounds. Based on the review, it is found the modern UAE (Ultrasound Assisted Extraction) process provides better quality than the other various conventional and modern extraction processes. UAE is an extraction process that does not use a heating process in its extraction which can damage the phenolic compounds and antioxidants. The results of the analysis of phenolic compounds using the UAE system have found betacyanin 17.64 mg, phenolic compounds 65.16 mg, flavonoid compounds 195 mg and antioxidants 620 mol. Thus, the recommended treatment to do is to use UAE extraction.

Improving the extraction efficiency and functional properties of wheat germ protein by ultrasound-assisted

This study optimised the conditions for ultrasound-assisted extraction (UAE) of defatted wheat germ protein (WGP) and evaluated its effect on the functional properties. Single-factor and orthogonal experiment designs were combined to optimise the UAE extraction condition. The extraction of WGP reached the highest level, at 88.66%, with a solid : liquid ratio of 1 : 25 g·mL–1, pH value of 9.0, ultrasonic time of 10 min, and ultrasonic power at 400 W. Under these conditions, albumin, globulin, prolamin, and glutenin accounted for 32.26, 28.52, 5.42, and 22.40% of total protein, respectively. In addition, this study compared the functional properties of WGP extracted by UAE with the results based on a commercially available soy protein (SP) isolate (SPI). The UAE of WGP had better oil absorption, foaming, and emulsifying properties. Therefore, UAE is a promising technique for food protein extraction because it can change the protein efficiencies and properties of the extract.

Modeling and Optimization of Phenolic Compounds from Sage (Salvia fruticosa L.) Post-Distillation Residues: Ultrasound- versus Microwave-Assisted Extraction

The essential oil production of Salvia fruticosa L. generates considerable amounts of post-distillation solid residues (PRES) which are rich in phenolic compounds. In the present work, the recovery of phenolic antioxidants from PRES by using Microwave-Assisted Extraction (MAE) and Ultrasound-Assisted Extraction (UAE) were separately optimized, according to the Box-Behnken experimental design. The optimization was based on extraction yield, total phenolic content (TPC), total flavonoid content (TFC), rosmarinic acid (RMA), carnosol (CARO), carnosic acid (CARA), and antioxidant activity. The optimal processing parameters were 72% and 68% ethanol, a 15- and 10-min extraction time, a 40 °C and 47 °C extraction temperature, and a 1:30 and 1:10 solid-to-solvent ratio, for MAE and UAE, respectively. Results showed that the levels of RMA, CARO, and CARA in UAE extracts were influenced mainly by ethanol concentration, extraction time, and extraction temperature, while MAE extracts were only influenced by the first two factors. Experimenting with the optimal conditions revealed MAE as more effective than UAE in the recovery of RMA and CARA. The experimental values were in good agreement with the predicted ones, indicating model efficacy in MAE and UAE optimization to effectively extract phenolic compounds from PRES for their further application in food and pharmaceutical industries.

Subcritical Water Extraction as an Effective Technique for the Isolation of Phenolic Compounds of Achillea Species

The genus Achillea has significant medical potential due to the presence of highly bioactive compounds in its chemical composition. To take advantage of plants’ biomedical potential, it is of great importance to use a proper extraction process. This study aimed to determine and compare the preliminary chemical composition of five different Achillea species extracted with two conventional (infusion and maceration) and two non-conventional (ultrasound-assisted extraction (UAE) and Subcritical water extraction (SWE)) techniques. The extracts were prepared using the previously described procedures for infusion, maceration, UAE and SWE extraction. For all extracts, the extraction yield (dry extract (DE)) was determined. The analyzed extracts were preliminarily chemically characterized spectrophotometrically in terms of total phenolic content (TPC) and total flavonoid content (TFC). The obtained results showed that non-conventional techniques delivered higher values of TPC and TFC than conventional. There is a statistically significant increase in DE and TPC content when applying SWE for all observed Achillea species. The highest DE value, 48.80 ± 1.76%, was observed for A. asplenifolia. The highest TPC values were observed after applying SWE: 93.63 ± 1.01 mg GAE/g DE for A. millefolium, and 90.12 ± 0.87 mg GAE/g DE for A. crithmifolia. The results for TFC revealed a statistically significant difference in values, with A. nobilis subsp. nelreichii as the sample with the highest content of TFC (11.11 ± 0.22 mg QE/g DE) when using UAE. Consequently, it could be concluded that SWE is a superior non-conventional extraction technique, and A. nobilis subsp. nerleichii presents as the most promising plant.

Ultrasound-Assisted Natural Deep Eutectic Solvents Extraction of Bilberry Anthocyanins: Optimization, Bioactivities, and Storage Stability.

Bilberry fruits (Vaccinium myrtillus L.) are one of the richest natural sources of anthocyanins and are widely used due to their pharmacological and nutritional properties. To ensure their maximum application potential, it is necessary to overcome the limitations of conventional extraction solvents and techniques. This study aimed to develop a green method for bilberry anthocyanin extraction using natural deep eutectic solvents (NaDES) integrated with ultrasound-assisted extraction (UAE) in order to define extraction conditions that will prevent decomposition of the anthocyanins or the loss of bioactivity. After a screening of ten different NaDES, choline chloride:sorbitol (1:1) was selected as the most effective. Furthermore, the influence analysis and optimization of the NaDES–UAE extraction conditions were carried out employing response surface methodology. The optimal conditions were found to be an extraction time of 37.63 min, a temperature of 48.38 °C, and 34.79% (w/w) water in NaDES. The extraction yields of target compounds under optimized extraction conditions were 0.27 mg/g DW of cyanidin-3-O-glucoside and 2.12 mg CGE/g DW of TAC. The obtained optimized extract showed promising radical scavenging and antimicrobial activity. A stability study with the optimized extract revealed that refrigerated storage at 4 °C in the dark provided the best anthocyanins preservation. Overall, the developed NaDES-UAE method showed promising application potential and can be considered as a high-efficiency green alternative to conventional anthocyanins extraction methods, enabling the preservation of active ingredients and the bioactivity of extracts.

Recovery of Antioxidants from Tomato Seed Industrial Wastes by Microwave-Assisted and Ultrasound-Assisted Extraction.

Tomato seed (TS) wastes are obtained in large amounts from the tomato processing industry. In this work, microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE) of antioxidant compounds from TS were optimized by using response surface methodology. The effect of MAE and UAE main extraction parameters was studied on total phenolic content (TPC) and antioxidant activity (DPPH) responses. Antioxidant, structural, morphological, and thermal properties of MAE and UAE extracts were evaluated. A great influence of ethanol concentration was observed in both extraction methods. Optimal MAE conditions were determined as 15 min, 80 °C, 63% ethanol and 80 mL, with a desirability value of 0.914, whereas 15 min, 61% ethanol and 85% amplitude (desirability = 0.952) were found as optimal conditions for UAE. MAE extracts exhibited higher TPC and antioxidant activity values compared to UAE (1.72 ± 0.04 and 1.61 ± 0.03 mg GAE g TS−1 for MAE and UAE, respectively). Thermogravimetric analysis (TGA) results suggested the presence of some high molecular weight compounds in UAE extracts. Chlorogenic acid, rutin and naringenin were identified and quantified by HPLC-DAD-MS as the main polyphenols found by MAE and UAE, showing MAE extracts higher individual phenolics content (1.11–2.99 mg 100 g TS−1). MAE and UAE have shown as effective green techniques for extracting bioactive molecules with high antioxidant activity from TS with high potential to be scaled-up for valorizing of TS industrial wastes.

Differential Metabolomic Fingerprinting of the Crude Extracts of Three Asteraceae Species with Assessment of Their In Vitro Antioxidant and Enzyme-Inhibitory Activities Supported by In Silico Investigations

The Asteraceae is a large family, rich in ornamental, economical, and medicinally valuable plants. The current study involves the analytical and pharmacological assessment of the methanolic extracts of three less investigated Asteraceae plants, namely Echinops ritro, Centaurea deflexa, and Tripleurospermum decipiens, obtained by three different extraction methodologies viz. maceration (MAC), ultrasound-assisted extraction (UAE), and homogenizer-assisted extraction (HAE). LC-MS-MS analysis of E. ritro, C. deflexa, and T. decipiens extracts led to the identification of ca. 29, 20, and 33 metabolites, respectively, belonging to flavonoids, phenolic acids, and fatty acids/amides. Although there were significant differences in the quantitative metabolite profiles in the extracts of E. ritro and T. decipiens based on the used extraction method, no significant variation was observed in the extracts of C. deflexa in the three implemented extraction techniques. The antioxidant activities of the nine extracts were assessed in vitro using six different assays viz. DPPH, ABTS, CUPRAC, FRAP, PDA, and metal chelation assay (MCA). The HAE/UAE extracts of E. ritro and the UAE/ MAC extracts of C. deflexa displayed the highest antioxidant activity in the DPPH assay, while the UAE extract of T. decipiens showed the strongest antioxidant activity in both the CUPRAC and MCA assays. The enzyme inhibitory activities of the nine extracts were studied in vitro on five different enzymes viz. tyrosinase, α-amylase, α-glucosidase, acetylcholinesterase (AChE), and butyrylcholinestrase (BChE), affecting various pathological diseases. Concerning C. deflexa, its MAC /UAE extracts showed the strongest inhibition on α-amylase, while its UAE/HAE extracts displayed strong inhibitory power on AChE. However, no significant difference was observed on their effects on tyrosinase or BChE. For T. decipiens, its UAE/HAE showed potent inhibition to α-glucosidase, MAC/ HAE significantly inhibited AChE and BChE, while UAE could strongly inhibit tyrosinase enzyme. For E. ritro, all extracts equally inhibited α-amylase and α-glucosidase, MAC/HAE strongly affected tyrosinase, HAE/MAC best inhibited BChE, while HAE inhibited AChE to a greater extent. Chemometric analysis using PCA plot was able to discriminate between the plant samples and between the implemented extraction modes. The in vitro enzyme inhibitory activities of the extracts were supported by in silico data, where metabolites, such as the lignan arctiin and the flavonoid vicenin-2, dominating the extract of C. deflexa, displayed strong binding to AChE. Similarly, chlorogenic and dicaffeoyl quinic acids, which are some of the major metabolites in the extracts of E. ritro and T. decipiens, bound with high affinity to α-glucosidase.

The Influence of Different Extraction Techniques on the Chemical Profile and Biological Properties of Oroxylum indicum: Multifunctional Aspects for Potential Pharmaceutical Applications.

Oroxylum indicum (L.) Kurz (Bignoniaceae), a traditional Chinese herbal medicine, possesses various biological activities including antioxidant, anti-inflammatory, antibacterial, and anticancer. In order to guide the practical application of O. indicum in the pharmaceutical, food, and cosmetic industries, we evaluated the effects of five different extraction techniques (maceration extraction (ME), oxhlet extraction (SOXE), ultrasound-assisted extraction (UAE), tissue-smashing extraction (TSE), and accelerated-solvent extraction (ASE)) with 70% ethanol as the solvent on the phytochemical properties and biological potential. The UHPLC-DAD Orbitrap Elite MS technique was applied to characterize the main flavonoids in the extracts. Simultaneously, the antioxidant and enzyme inhibitory activities of the tested extracts were analyzed. SOXE extract showed the highest total phenolic content (TPC, 50.99 ± 1.78 mg GAE/g extract), while ASE extract displayed the highest total flavonoid content (TFC, 34.92 ± 0.38 mg RE/g extract), which displayed significant correlation with antioxidant activity. The extract obtained using UAE was the most potent inhibitor of tyrosinase (IC50: 16.57 ± 0.53 mg·mL−1), while SOXE extract showed the highest activity against α-glucosidase (IC50: 1.23 ± 0.09 mg·mL−1), succeeded by UAE, ME, ASE, and TSE extract. In addition, multivariate analysis suggested that different extraction techniques could significantly affect the phytochemical properties and biological activities of O. indicum. To sum up, O. indicum displayed expected biological potential and the data collected in this study could provide an experimental basis for further investigation in practical applications.

Ultrasound assisted extraction of carotenoids from green and orange biomasses of Dunaliella Salina DunaDZ1

Microalgae are described as a potential alternative source of bioactive compounds that are environmentally friendly. Dunaliella on its own is well known due to its potential to accumulate large amounts of carotenoids, especially β-carotene. Green and orange biomasses from a new Dunaliella salina strain DunaDZ1 isolated from an Algerian Salt Lake were evaluated for carotenoids composition and antioxidant activity. Ultrasound-Assisted Extraction (UAE) was employed using different extracting solvents. Furthermore, UAE extracts were then analyzed for their chemical composition by TLC, HPLC-DAD and for the antioxidant activity. Lutein was the main carotenoid in the green biomass, with the highest amount for ethyl acetate extract (393.19 mg/g). However, for the orange biomass, the main carotenoid was trans, β-carotene (131.83 mg/g) in the acetonic extract. Moreover, several others carotenoids were detected, belonging to xanthophylls and carotenes. Additionally, ultrasonic-assisted extraction with ethyl acetate produced the extract with the highest antioxidant activity for both D. salina biomasses. These extracts could be used as a natural antioxidant and as an ingredient for functional foods formulation.