Search Results (181)

Prickly pear (Opuntia ficus-indica (L.) Mill.) generates substantial agro-industrial by-products, such as press cake, seed, and oil, that remain underexploited despite their recognized phytochemical richness. This study reports the systematic optimization, characterization, and bioactivity profiling of flavonoid-rich extracts recovered from these three matrices. A Box–Behnken design (BBD) coupled with response surface methodology (RSM) was applied to optimize the ultrasound-assisted extraction (UAE) of total flavonoid content (TFC) from press cake using a natural deep eutectic solvent (NADES: fructose–glycerol–sorbitol–water and FGSH), selected through an initial screening of fifteen solvent systems. The quadratic polynomial model showed excellent fit (R² = 0.9852; R²adj = 0.9687; MAPE = 1.31%; Durbin–Watson = 1.857), and optimal extraction conditions were established at 37.6 min extraction time, 35.6% ultrasonic power, and 29.4 °C, yielding a maximum predicted TFC of 54.78 ± 0.49 mg quercetin equivalents (QE)/mL. HPLC-DAD analysis of the press cake extract revealed five isorhamnetin derivatives as the dominant flavonoids, with isorhamnetin-3-O-glucoside (23.18 ± 0.12 mg/g DW) and isorhamnetin-3-O-rutinoside (13.80 ± 0.28 mg/g DW) as the most abundant. Comprehensive bioactivity assessment demonstrated significant antioxidant capacities (CUPRAC: 191.35 ± 3.22 µM AAE; ORAC: 184.44 ± 3.44 µM TE; DPPH: 103.47 ± 9.98 µM TE for press cake extract), potent in cellulo ROS/RNS suppression in a yeast UV-stress model (85.9 ± 1.0% inhibition for press cake), and differential tyrosinase inhibition across fractions (press cake: 32.8%; seed: 57.5%; oil: 83.8%), highlighting the oil as a potent anti-melanogenic ingredient. In silico safety prediction (ProTox-II/pkCSM) confirmed the favorable toxicity profiles of all identified isorhamnetin derivatives (LD₅₀ > 5000 mg/kg; Toxicity Class V). These results collectively position Opuntia ficus-indica by-products as high-value natural sources of bioactive flavonoids with applications in cosmetic, nutraceutical, and dermatological formulations. Full article

Deep eutectic solvent (DES) extraction is a green and efficient technology. As a substitute for organic reagents, DESs are widely used to extract active ingredients from traditional Chinese medicine. This study established an environmentally friendly and efficient method for extracting astaxanthin (AST) from Phaffia rhodozyma (PR) using ultrasound-assisted deep eutectic solvents (DESs-UAE). The astaxanthin content was determined by high-performance liquid chromatography (HPLC). Six types of deep eutectic solvents composed of DL-menthol and selected hydrogen bond donors were prepared and evaluated, among which the DL-menthol–acetic acid system showed superior extraction performance. Response surface methodology (RSM) was employed to optimize extraction parameters (ultrasonic power, time, and temperature), and the optimal conditions were determined as follows: ultrasonic power 420 W, ultrasonic time 20 min, and ultrasonic temperature 60 °C, achieving an AST extraction rate of 62% (2.49 mg/g). Compared with conventional organic solvent extraction, DESs exhibited a significantly higher AST extraction rate from PR, except for dimethyl sulfoxide (DMSO). Scanning electron microscopy (SEM) analysis demonstrated that DES-UAE treatment disrupted the cellular structure of PR, resulting in numerous surface pores; this facilitated the release of intracellular bioactive components and significantly improved AST extraction efficiency. The PR extract showed no significant cytotoxicity and could effectively promote L929 cell proliferation. It concentration-dependently increased superoxide dismutase (SOD) activity and decreased malondialdehyde (MDA) content in H₂O₂-induced oxidative stress L929 cells, thereby alleviating oxidative damage. Additionally, it concentration-dependently upregulated type I collagen expression in these cells, ameliorated the decline in collagen synthesis function, and exerted a protective effect against cellular oxidative damage. This study provides a green alternative to toxic solvents and offers important theoretical and chemical support for the extraction of natural products and the high-value utilization of Phaffia rhodozyma (PR). Deep eutectic solvents have emerged as promising green alternatives to hazardous organic solvents, yet hydrophobic DESs tailored for lipophilic astaxanthin extraction from Phaffia rhodozyma and the linkage between extraction performance and anti-aging bioactivity remain insufficiently explored. Here, an ultrasound-assisted hydrophobic deep eutectic solvent extraction strategy was constructed to acquire astaxanthin, aiming to overcome low efficiency and environmental risks of conventional organic extraction techniques. Six DL-menthol-based DESs were prepared and screened, and DL-menthol–acetic acid possessed the optimal extraction capacity. Key extraction parameters were optimized via response surface methodology, and the maximum astaxanthin extraction recovery reached 62% (2.49 mg/g) under 420 W ultrasonic power, 20 min treatment and 60 °C. This yield was markedly higher than that of most common organic solvents; though comparable extraction effect was obtained with DMSO, the adopted DES possessed outstanding low-toxic and biodegradable superiorities that DMSO cannot match. SEM characterization verified that the combined treatment destroyed yeast cell structure and formed porous morphology, which accelerated intracellular astaxanthin release and accounted for improved extraction efficiency. Biological assays proved the extract possessed good biosafety and proliferation-promoting effect on L929 cells. It effectively relieved cellular oxidative injury by elevating the SOD level and reducing MDA accumulation in oxidative damaged cells, and upregulated type I collagen expression to mitigate aging-related collagen loss. This work develops an eco-friendly and high-efficiency extraction route for lipophilic active substance, confirms the practical value of hydrophobic DES, and provides experimental basis for high-value utilization of Phaffia rhodozyma resources. Full article

Pear pomace, a major by-product of the juice processing, represents a valuable yet underexploited source of bioactive compounds. In this study, ultrasound-assisted extraction (UAE) was optimized using response surface methodology to enhance the recovery of phenolic compounds from pear pomace powder with aqueous ethanol as the extraction solvent. A Box–Behnken design was employed to evaluate the effects of ethanol concentration (40–80%), extraction time (30–90 min), and ultrasonic power (48–144 W) on total phenolic content and DPPH radical scavenging activity. The results demonstrated that the negative quadratic effect of ultrasonic power on phenolic extraction yield exhibited the highest level of statistical significance. Extraction using 40% ethanol for 64.45 min at a power intensity of 117.6 W enabled the optimal recovery of phenolic constituents, yielding 280.1 mg GAE/L in the extracts. Using HPLC, the study explored how variations in ethanol concentration and extraction time affect the phenolic composition of the extracts. Chlorogenic acid, rutin and epicatechin were found to be the major polyphenolic compounds. Overall, pear pomace demonstrated strong potential as a low-cost source of phenolic compounds, and the optimized UAE process proved to be an efficient and robust approach for maximizing phenolic recovery. Full article

This study aimed to intensify the ultrasound-assisted extraction (UAE) of rutin, chlorogenic acid, ferulic acid, and total phenolic compounds (TPCs) from mangaba (Hancornia speciosa Gomes) fruit. Based on a univariate experimental screening, the selected operational conditions for the recovery of TPC, chlorogenic, and ferulic acids were achieved at an ultrasonic frequency of 40 kHz with an output power of 145 W (100% potency), atmospheric pressure, and 35 °C for 30 min. Under these conditions, the extraction yields were 1540.46 ± 19.48 mg GAE/100 g for TPC, 183.86 ± 4.53 mg/100 g for chlorogenic acid, and 2.19 ± 0.3 mg/100 g for ferulic acid. Conversely, the highest rutin concentration (157.17 ± 4.68 mg/100 g) was obtained at 145 W, atmospheric pressure, and 30 °C for 30 min. Increasing the ultrasonic potency from 30% to 100% significantly enhanced the extraction of chlorogenic acid, ferulic acid, and TPC, whereas it had no significant impact on rutin recovery. These results demonstrate that time, temperature, and ultrasonic potency are critical drivers of process efficiency. This work establishes a technical baseline for the industrial scale-up of UAE, highlighting its potential for the high-yield production of bioactive extracts from native Brazilian fruits for the pharmaceutical and food sectors. Full article

To promote green chemistry and improve the utilization of plant resources, flavonoids from Dalbergia pinnata (Lour.) Prain were extracted in this study by combining NADES (natural deep eutectic solvents) with UAE (ultrasound-assisted extraction). Among the 13 synthesized NADES, choline chloride (ChCl)–urea (NADES-13) exhibited the highest extraction rate, outperforming traditional organic solvents. The optimal conditions determined by response surface methodology (RSM) were as follows: ChCl–urea molar ratio of 1:3, moisture content of 60%, liquid-to-material ratio of 28.5 mL/g, ultrasonic extraction time of 49 min, and temperature of 62 °C. Under these conditions, the extraction rate reached 117.95 ± 5.97 mg/g, a 73.5% improvement compared with 80% EtOH extraction. The comparison of the two algorithms showed that RSM (R = 0.9981, RMSE = 0.6570) had better fitting accuracy and prediction stability under small sample conditions than MLP (R = 0.9427, RMSE = 5.261) and RF (R = 0.9431, RMSE = 5.2442). DFT (density functional theory) analysis demonstrated that hydrogen bonds, Van der Waals forces, and cation–π interactions mediate the interaction between NADES-13 and flavonoids. Ultrasonic cavitation-induced cell wall damage and the hydrogen-bond network of NADES-13 were confirmed separately by SEM (scanning electron microscopy) and FTIR (Fourier transform infrared spectroscopy). In vitro experiments showed that the extract possessed concentration-dependent antioxidant activity and strong antibacterial activity, with an inhibition rate of 96.87 ± 5.09% against Escherichia coli at a concentration of 0.04 mg/mL. In this study, a “Smart Optimization–Molecular Mechanism–Activity Verification” green extraction system was developed, which offers an efficient and environmentally friendly strategy for extracting plant bioactive components and contributes to the progress of green chemistry. Full article

Salvia transsylvanica was investigated as a source of bioactive metabolites by optimizing hydroethanolic ultrasound-assisted extraction (UAE) and comparing it with classical preparations. A D-optimal quadratic design was applied to aerial parts to evaluate the effects of ultrasonic amplitude, extraction time, and ethanol concentration on total phenolic content (TPC) and antioxidant capacity (ABTS, DPPH), yielding models with good fit and predictive ability. The optimal conditions (24% amplitude, 12 min, 38% ethanol) were then applied to aerial parts, flowers, and leaves, affording extracts with high TPC values (up to 240 mg GAE/g extract) and antioxidant activities comparable to aqueous infusions and 70% hydroethanolic macerates, with FRAP and DPPH values above 400 mg TE/g dw. Targeted HPLC-MS analysis revealed a Salvia-typical phenolic profile dominated by rosmarinic acid (up to 20 mg/g extract), methyl rosmarinate, caffeic acid derivatives, salvianolic acid K, and flavone glycosides (luteolin-7-O-glucoside and apigenin-7-O-glucoside), with leaf extracts generally richest in phenolics and antioxidant capacity. Conversely, macerates showed superior recovery of phytosterols and tocopherols. The extracts displayed moderate, selective antibacterial effects, particularly against Staphylococcus aureus, with inhibition zones up to 4 mm for flower-based preparations. Overall, UAE emerged as an efficient, green strategy for a rapid recovery of phenolic antioxidants from S. transsylvanica, while classical maceration complements it for lipophilic constituents, supporting the valorization of this endemic sage. Full article

Cocoa pod husk (CPH), a major agro-industrial residue, contains valuable bioactive compounds whose recovery can support sustainable waste valorization. This study evaluated the influence of increasing ethanol concentrations on the ultrasound-assisted extraction (UAE) of bioactive compounds from CPH and their antioxidant, antihypertensive, and antihyperglycemic activity. Dried and milled CPH was extracted using ethanol–water mixtures (0–100% ethanol) under fixed ultrasonic conditions. Cocoa pod husk powder characterization and the resulting extracts were analyzed in terms of chemical composition (lignocellulosic compounds, proximate and elemental composition, and bromatological composition), antioxidant capacity, and in vivo antihypertensive and antihyperglycemic effects in Wistar rats. The results showed that solvent polarity strongly modulated extraction efficiency: absolute ethanol yielded the highest phenolic (171.43 mg GAE/g) and flavonoid (132.05 mg QE/g) content, whereas hydroalcoholic mixtures, particularly 50:50, enhanced overall antioxidant performance, especially in FRAP. The chemical analysis results showed the selective recovery of compounds such as quercetin, hesperidin, and theobromine, and FTIR-PCA results revealed distinct solvent-dependent chemical profiles. In vivo assays indicated modest blood pressure stabilization and a more pronounced antihyperglycemic effect after chronic administration. Overall, UAE proved an effective, rapid, and solvent-efficient method for CPH valorization, highlighting its potential for producing natural antioxidants applicable to food, nutraceutical, and cosmetic formulations. Full article

Camellia hakodae Ninh flowers are an endemic Vietnamese species with limited phytochemical and biological characterization. This study aimed to characterize the phytochemical profile and evaluate antioxidant and anti-inflammatory activities of the total flower extract. Ultrasonic-assisted extraction (UAE) and maceration with methanol and ethanol at different concentrations were carried out to evaluate the efficiency of extracting total phenolic content (TPC) and total flavonoid content (TFC), quantified by colorimetric assays, along with the antioxidant and anti-inflammatory activities of the resulting extracts. The highest TPC (94.9 ± 4.5 mg GAE/g) and TFC (3.1 ± 0.2 mg QE/g) were obtained using UAE with 70% methanol, while maceration with 70% ethanol showed comparable TPC values. The optimized extract exhibited strong antioxidant activity with an IC₅₀ of 29.06 µg/mL, close to that of ascorbic acid (28.16 µg/mL) and significant anti-inflammatory activity in the proteinase inhibition assay (IC₅₀ = 2.72 mg/mL) compared to acetylsalicylic acid (IC₅₀ = 3.16 mg/mL). GC-MS and LC-QTOF-MS/MS analyses revealed diverse metabolites, including phenolic acids, flavonoids, fatty acids, terpenoids, and nitrogen-containing compounds, with representative constituents, such as quinic acid, catechins, flavonol glycosides, and loliolide, providing strong chemical evidence for the observed bioactivities. This integrated study demonstrates that C. hakodae flower is a rich source of multifunctional bioactive compounds and highlights its strong potential for applications in nutraceuticals, functional foods, and cosmeceuticals. Full article

Hedera helix (HE) contains diverse bioactive constituents, including triterpenoid saponins, flavonoids, and phenolic acids, which exhibit various pharmacological activities. In this study, ultrasound-assisted extraction (UAE) combined with natural deep eutectic solvent (NADES) was employed to enhance the extraction efficiency and elucidate the underlying mechanisms. Among the tested formulations, a ternary system composed of malonic acid (Mal), N,N′-dimethylurea (DMU), and 1,4-butanediol (1,4-BDO) achieved the highest efficiency for extracting eight target compounds from the HE leaves. In addition, the key interactions among NADES components were confirmed by Fourier-transform infrared (FT-IR) spectroscopy, providing valuable insights into the extraction mechanism. The UAE process was systematically optimized through single-factor experiments. Subsequently, response surface methodology (RSM) identified the optimal conditions as ultrasonic time of 45 min, solid/liquid ratio of 1:54 g/mL, and ultrasonic temperature of 42 °C. Scanning electron microscopy (SEM) elucidated the microstructural alterations in plant cell walls induced by NADES-UAE, alongside the enhanced penetration and disruption mechanisms. In vitro bioactivity revealed that the NADES-extracted HE exerted strong inhibitory effect on HT-29 colon cancer cells. Overall, these findings demonstrate the high effectiveness and sustainability of NADES-UAE for extracting HE bioactive compounds and provide valuable implications for the industrial-scale production of plant-based functional products. Full article

The valorization of wine by-products aligns with circular bioeconomy principles. This study investigates the ultrasound-assisted aqueous extraction (UAE) of bioactive compounds and cell wall polysaccharides from Syrah grape stems (Vitis vinifera L.) to produce polysaccharide extracts with the intrinsic potential to form cellulose-rich gels with enhanced antioxidant properties. Extractions were performed at three temperatures (10, 20, and 50 °C) and three ultrasonic power densities (120, 206, and 337 W/L), and compared to conventional extraction (CE, 200 rpm). The results demonstrated that UAE significantly accelerated the extraction kinetics for total phenolics (TP), flavonols, and antioxidant capacity (ABTS, FRAP), achieving up to a 3.1-fold increase in TP yield at 20 °C. Notably, UAE at 337 W/L and 20 °C produced antioxidant levels equivalent to those obtained by CE at 50 °C, enabling high efficiency at lower, compound-preserving temperatures. Carbohydrate analysis revealed that the extracts were inherently “cellulose-rich” (glucose ~49–52 mol%), with co-extracted pectins and hemicelluloses constituting a composite polysaccharide matrix with inherent gel-forming capacity, as evidenced by its composition. While total polysaccharide yield was maximized at 10 °C, UAE’s primary effect was the facilitation of extraction and potential structural modification of polymers rather than increasing bulk yield. The process reduced extraction times by 3- to over 6-fold to achieve equivalent bioactive yields compared to CE. This work establishes UAE with water as a process aligned with green chemistry principles, an efficient strategy for the integrated, one-step recovery of antioxidant phenolics and gel-forming polysaccharides from grape stems, transforming this underutilized residue into a multifunctional extract precursor for cellulose-rich hydrogels suitable for food and pharmaceutical applications. Full article

Within the framework of green chemistry and wild fruit valorization, this study optimizes the extraction of bioactive compounds from Prunus spinosa L. fruits using glycerin-based ultrasound-assisted extraction (UAE). Response Surface Methodology (RSM) and Artificial Neural Networks (ANN) were comparatively employed to model the process. Significant improvements in extraction efficiency were achieved, with total phenolic content increasing from 9.28 to 23.22 mg GAE/g DW, total flavonoid content from 6.53 to 21.65 mg CE/g DW, and antioxidant activity (DPPH assay) from 57.04% to 86.34%. While both models performed well, ANN demonstrated slightly higher predictive accuracy, highlighting its potential for capturing complex, non-linear relationships in the extraction process. We identified the optimal extraction conditions as 9 min extraction time, 100% ultrasonic amplitude, and 40% water in glycerin, and these conditions were experimentally validated. UHPLC-DAD-HRMS/MS profiling revealed a rich phytochemical fingerprint dominated by phenolic acids, caffeoylquinic acid derivatives, and flavonol glycosides, and revealed largely overlapping qualitative phytochemical profiles between hydroglyceric and ethanolic extracts. Comparative extraction using 70% ethanol under identical conditions resulted in lower TPC, TFC, and antioxidant activity, indicating the improved efficiency of glycerin under the investigated conditions. Overall, the optimized glycerin-based UAE provides a sustainable, food-safe approach for extracting bioactive compounds from underutilized P. spinosa fruits. These results support its application in functional foods and in nutraceutical and cosmetic formulations. Full article

This study aimed to investigate the effects of ultrasound-assisted extraction (UAE) on the physicochemical properties, biological activities, and intestinal flora regulatory capacity of jackfruit polysaccharides (JPs). Under optimized UAE conditions (liquid-to-solid ratio 30 mL/g, extraction time 30 min, power 90 W), the yield of JP reached 8.70 ± 0.11%. Compared with hot-water-extracted jackfruit polysaccharides (HAE-JPs), ultrasonic-assisted extracted jackfruit polysaccharides (UAE-JPs) exhibited a lower molecular weight, a smaller particle size, and a significant 11.5-fold increase in galacturonic acid content. Structural analyses confirmed that UAE-JPs retained a triple-helix and highly branched conformation but with enhanced exposure of acidic monosaccharides. These structural modifications contributed to superior antioxidant activity and enzyme inhibition ability, demonstrated by its lower IC₅₀ values against DPPH, ABTS radicals, and α-glucosidase. Crucially, in vitro fecal fermentation revealed that UAE-JPs and HAE-JPs differentially modulated the gut microbiota. UAE-JPs preferentially promoted the proliferation of Lactobacillus (an increase of 27.04%) and Bifidobacterium, facilitating short-term acidification. In contrast, HAE-JPs enriched butyrate-producing bacteria like Clostridium (increase of 18.56%). Both polysaccharides significantly inhibited the growth of Fusobacterium (a decrease of 5.23%) related to cancer. Consequently, this study establishes UAE as a green and efficient technique capable of not only modifying the structure of JPs but also precisely tailoring their prebiotic functionality, which ultimately demonstrates the potential of UAE-JPs as a functional food ingredient with enhanced bioactivity. Full article

This study aimed to enhance the extraction efficiency and elucidate the mechanism of ultrasound-assisted extraction (UAE) of taxanes from Taxus chinensis by natural deep eutectic solvents (NADES). The processes of kinetics and thermodynamics were systematically investigated. These extractions adhered to a pseudo-second-order kinetic model (R² > 0.972), with intraparticle diffusion identified as the dominant mechanism. Key parameters such as temperature, ultrasonic power, and solid/liquid ratio significantly improved the effective diffusion coefficient (D_e) and mass transfer coefficient (K_T), reaching values of 6.21 × 10⁻⁹ m²/s and 4.14 × 10⁻³ m/s, respectively. A high Biot number (B_i > 59.21) confirmed that internal diffusion is the rate-determining step. Thermodynamic analysis indicated that the process is endothermic (ΔH > 0), irreversible (ΔS > 0), and spontaneous (ΔG < 0). These results elucidate the underlying mechanisms of UAE and establish a foundational framework for its industrial-scale implementation. Full article

Thunbergia laurifolia Lindl. is a plant known for its promising biological activity, including antioxidant and anti-inflammatory activities, and a rich source of rosmarinic acid (RA). The extraction of T. laurifolia for cosmetic and skincare products using conventional solvents has encountered difficulties, including safety concerns, skin irritation, undesirable odors, and inefficient extraction. In this work, 14 types of natural deep eutectic solvents (NaDESs) with varying compositions and ratios were investigated to compare their efficiency in extracting RA from T. laurifolia by HPLC analysis. The NaDES with the highest extraction efficiency was further utilized in ultrasonic-assisted extraction (UAE), and the extraction parameters were optimized using response surface methodology. The optimized RA content and DPPH scavenging activity were predicted by response surfaces methodology to be 7.52 mg/g DW and 37.6 mg TE/g DW, respectively. The optimal extraction condition was achieved using a propylene glycol-lactic acid NaDES (at an 8:1 molar ratio) with 37% (w/w) H₂O, a 30 mL/g liquid-to-solid ratio, an 80 °C extraction temperature, and a 32 min extraction time. The optimized extract was proved to suppress ROS in H₂O₂-induced keratinocytes. The extract demonstrated robust stability against basic, oxidative, and photolytic stresses, and maintained long-term chemical stability up to 90 days. This study introduces a new green solvent for the effective extraction of T. laurifolia, thereby improving the safety and quality of the extracts for skincare and cosmetic products. Full article

This study examined the relationship between flavonoid content and the antiviral effects of plant extracts against the dengue virus (DENV). Fourteen extracts from medicinal plants cultivated in Colombia, which were prepared by ultrasonic-assisted solvent extraction (UAE) and supercritical fluid extraction (SFE) were included. UHPLC/ESI-Q-Orbitrap-MS analysis identified forty-six flavonoids. Antiviral effect on viral adsorption was evaluated using the DENV-CPE-based assay. UAE extracts of Scutellaria coccinea, Scutellaria incarnata, and Lippia alba contained higher amounts of flavonoid glycosides (from 97.0% to 87.9%) than aglycones, and showed antiviral effect (IC₅₀: 3.0 to 65 µg/mL; SI: 0.4 to 71). In contrast, UAE and SFE extracts from Lippia origanoides had higher content of flavonoid aglycones (41.7% to 93.4%) than glycosides (0.0 to 58.3%) and showed no antiviral effect. Cluster and one-way ANOVA analyses revealed a positive correlation between increased levels of flavone glycosides in the extract and a strong antiviral effect. Docking analyses (AutoDock Vina) revealed that the flavonoid glycosides exhibited a higher binding affinity for the target proteins (E, Gas6-Axl, clathrin, and dynamin) than the aglycones did. This study establishes a scientific basis for using extracts rich in flavonoid glycosides, particularly flavones, as starting points for developing plant-based therapies to treat dengue. Full article