Search Results (4,972)

Deep eutectic solvents (DES) represent an innovative and environmentally friendly approach for chitin isolation. Chitin is a natural nitrogenous polysaccharide, characterized by its abundance of amino and hydroxyl groups. The hydrogen bond network in DES can disrupt the crystalline structure of chitin, facilitating its isolation from bioresources by dissolving or degrading other components. DES are known for their low cost, natural chemical constituents, and recyclability. Natural deep eutectic solvents (NADES), a subclass of DES made from natural compounds, offer higher biocompatibility, biodegradability, and the lowest biotoxicity, making them highly promising for the production of eco-friendly chitin products. This review summarized studies on chitin isolation by DES, including reviews of biomass resources, isolation conditions (raw materials, DES compositions, solid–liquid ratios, temperature, and time), and the physicochemical properties of chitin products. Consequently, we have concluded that tailoring an appropriate DES-based process on the specific composition of the raw material can notably improve isolation efficiency. Acidic DES are particularly effective for extracting chitin from materials with high mineral content, such as crustacean bio-waste; for instance, the choline chloride-lactic acid DES achieved purity levels comparable to those of commercial chemical methods. By contrast, alkaline DES are better suited for chitin isolation from protein-rich sources, such as squid pens. DES facilitate calcium carbonate removal through H⁺ ion release and leverage unique hydrogen bonding interactions for efficient deproteination. Among these, potassium carbonate-glycerol DES have demonstrated optimal efficacy. Nonetheless, further comprehensive research is essential to evaluate the environmental impact, economic feasibility, and safety of DES application in chitin production. Full article

Anthocyanin is an important flavonoid with antioxidant, anticancer, and anti-inflammatory properties. This research investigates the anthocyanin content of Cavendish banana inflorescence, a by-product often discarded as agricultural waste. The study employs two drying methods, namely oven-drying and freeze-drying, followed by accelerated solvent extraction using acidified water and methanol. Liquid chromatography-mass spectroscopy (LC-MS) results confirm banana inflorescence as a rich source of anthocyanins. According to LC-MS analysis, freeze-dried banana inflorescence extracted in methanol at 80 °C exhibits the highest anthocyanin content (130.01 mg/100 g). This sample also demonstrates superior characteristics, including a chroma value of 40.02 ± 0.01, a redness value of 38.09 ± 0.16, 18.46 ± 0.02 °Brix, a total phenolic content of 42.5 ± 1.00 mg/g, expressed as gallic acid equivalents, and a total antioxidant activity of 71.33 ± 0.08% when assessed with the DPPH method. Furthermore, the study identifies the predominant anthocyanin as cyanidin, along with the presence of other anthocyanins such as delphinidin (Dp), malvidin (Mv), petunidin (Pt), pelargonidin (Pg), and peonidin (Pn). Interestingly, the extracted anthocyanins demonstrate pH sensitivity, changing from red to brown as pH increases. These findings highlight the potential of utilizing Cavendish banana inflorescence for anthocyanin extraction, offering sustainable waste valorization methods with promising applications in biomimetics and bioinspiration fields. Full article

Bromophenols, which belong to the family of phenolic compounds, are halogenated secondary metabolites characterized by the incorporation of bromine atoms into the phenol ring structure, resulting in unique chemical properties. These compounds, synthesized as secondary metabolites by algae, exhibit different isomeric forms due to bromine substitution at different positions within the phenol ring, showing variability among species. Bromine substitution not only confers specific chemical properties but also plays an important role in the ecological functions of bromophenols by inducing increased lipophilicity, which affects solubility and reactivity, an adaptive response to external conditions. Certain genera of red algae, such as Gracilaria and Rhodomela, have been identified as important sources of bromophenols. Research on bromophenols involves extraction, commonly using solvents such as methanol or methanol-dichloromethane, and identification and structural elucidation using advanced analytical techniques such as mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy for the precise determination of structure and configuration. Bromophenols display diverse biological activities, highlighting antimicrobial, antidiabetic, antiviral and antioxidant properties, which are closely related to their specific chemical structure. The importance of understanding the chemical group of bromophenols is underlined by their role in chemical defense mechanisms, contributing to potential biotechnological applications and broader contributions to the marine ecosystem. Therefore, this study is aimed to review the chemical characteristics and biological properties of bromophenols in red algae. Full article

Biofilms are bacterial communities on surfaces within an extracellular matrix. Targeting biofilm-specific bacteria is crucial, and natural compounds with reported antibiofilm activity have garnered significant interest. The study evaluated the antibacterial and antibiofilm activity of Erythrina senegalensis leaf extract against multidrug-resistant (MDR) Gram-negative bacteria, including Salmonella typhimurium, Salmonella typhi, Salmonella enteritidis, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The leaf extract was prepared using aqueous and ethanol solvents, and qualitative phytochemical screening revealed the presence of various bioactive compounds such as tannins, saponins, cardiac glycosides, flavonoids, terpenoids, alkaloids, anthraquinone, reducing sugar, and ketones. A Kirby–Bauer disc diffusion assay was performed to test the susceptibility of antibiotics, and the antibacterial efficacy of the aqueous and ethanol extracts of E. senegalensis was determined using the cup-plate method, while the antibiofilm activities were determined using the crystal violet titer-plate method. The aqueous and ethanol extracts of Erythrina senegalensis revealed the presence of tannins, saponins, cardiac glycosides, flavonoids, terpenoids, alkaloids, anthraquinone, reducing sugar, and ketones. The study found that the Gram-negative bacteria isolates that were MDR were S. typhimurium, S. enteritidis, and P. aeruginosa, while K. pneumoniae was resistant to beta-lactam and fluoroquinolones, and S. typhi was sensitive to all antibiotics tested. Statistically, susceptibility to antibiotics had an inverse, weak, and significant relationship with biofilm production (r = −0.453, −0.106, −0.124, −0.106, −0.018, n = 10, p < 0.05). The aqueous extract showed good biofilm inhibition against K. pneumoniae and P. aeruginosa, and poor biofilm inhibition against S. enteritidis, while S. typhimurium and Salmonella typhi exhibited no biofilm inhibition. The ethanol extract did not demonstrate any antibiofilm activity against the tested Gram-negative pathogens. The study suggests that the Gram-negative bacteria’s capacity to form biofilms is negatively associated with their antibiotic resistance phenotypes, and the aqueous extract of E. senegalensis exhibited moderate antibiofilm activity against K. pneumoniae, P. aeruginosa, and S. enteritidis. Full article

Different solvents water, ethanol and ethanol/water (6:4 v/v), were compared in the extraction of pomegranate peels and seeds (PPS) in terms of recovery yields, antioxidant properties, and antimicrobial action against typical spoilage bacterial and fungal species. The best performing extract (ethanol/water (6:4 v/v) was shown to contain mostly ellagic acid and punicalagin as phenolic compounds (5% overall) and hydrolysable tannins (16% as ellagic acid equivalents) and was able to inhibit the growth of the acidophilic Alicyclobacillus acidoterrestris at a concentration as low as 1%. The preservation of the organoleptic profile of A. acidoterrestris-inoculated apple juice with extract at 1% over 20 days was also observed thanks to the complete inhibition of bacterial growth, while the extract at 0.1% warranted a significant (40%) inhibition of the enzymatic browning of apple smoothies over the first 30 min. When incorporated in whey proteins’ isolate (WPI) at 5% w/w, the hydroalcoholic extract conferred well appreciable antioxidant properties to the resulting coating-forming hydrogel, comparable to those expected for the pure extract considering the amount present. The WPI coatings loaded with the hydroalcoholic extract at 5% were able to delay the browning of cut fruit by ca. 33% against a 22% inhibition observed with the sole WPI. In addition, the functionalized coating showed an inhibition of lipid peroxidation of Gouda cheese 2-fold higher with respect to that observed with WPI alone. These results open good perspectives toward sustainable food preservation strategies, highlighting the potential of PPS extract for the implementation of WPI-based active packaging. Full article

The squash, C. moschata, is a type of pumpkin that grows easily in milpas—small, polyculture fields in Guatemala. Excavations carried out in pre-Columbian mounds in Uaxactún, Petén, indicate that squash has been cultivated and consumed for more than 5000 years. Today, both the pulp and the seed are still used as food; seeds are processed by hand and sold as toasted seed, or as toasted and ground seed with added salt, which is called pepita. The seed is used as a flavoring and thickening ingredient in sauces and pepita is used as an accompaniment to fresh fruit. This work aimed to provide updated information on the nutritional compositions of squash seeds and pepita in popular markets in the north, center, west, and southeast of Guatemala. The moisture content was determined in a convection oven at 60 °C, the ash by combustion in furnace at 450 °C, the protein by Kjeldahl method, fat by solvent extraction in the goldfish apparatus, and minerals by atomic absorption spectroscopy; and a UV/VIS colorimeter. The moisture content in seeds and pepita were 5.67% and 4.65%; ash 4% and 6.24%; protein 32.9% and 29.21%; lipids 32.07% and 30.22%, respectively. There was a higher content of macrominerals in pepita than in seeds, due to the salt addition. Comparing the nutritional results of the dry seed with those reported in the Food Composition Table for Central America, differences in protein and fat content are greater than 10%. Full article

The measurement of selected norepinephrine metabolites, such as 3,4-dihydroxyphenylglycol (DHPG), 3-methoxy-4-hydroxyphenylethylenglycol (MHPG), and vanillylmandelic acid (VMA), in biological matrices—including urine—is of great clinical importance for the diagnosis and monitoring of diseases. This fact has forced researchers to evaluate new analytical methodologies for their isolation and preconcentration from biological samples. In this study, the three most popular extraction techniques—liquid-liquid extraction (LLE), solid-phase extraction (SPE), and a new 3D-printed system for dispersive solid-phase extraction (3D-DSPE)—were investigated. Micellar electrokinetic chromatography (MEKC) with a diode array detector (DAD) at 200 nm wavelength was applied to the separation of analytes, allowing for the assessment of the extraction efficiency (R) and enrichment factor (EF) for the tested extraction types. The separation buffer (BGE) consisted of 5 mM sodium tetraborate decahydrate, 50 mM SDS, 15% (v/v) MeOH, 150 mM boric acid, and 1 mM of 1-hexyl-3-methylimidazolium chloride (the apparent pH of the BGE equaled 7.3). The EF for each extraction procedure was calculated with respect to standard mixtures of the analytes at the same concentration levels. The 3D-DSPE procedure, using DVB sorbent and acetone as the desorption solvent, proved to be the most effective approach for the simultaneous extraction and determination of the chosen compounds, achieving over 3-fold signal amplification for DHPG and MHPG and over 2-fold for VMA. Moreover, all extraction protocols used for the selected norepinephrine metabolites were estimated and discussed. It was also confirmed that the 3D-DSPE-MEKC approach could be considered an effective tool for sample pretreatment and separation of chosen endogenous analytes in urine samples. Full article

Opuntia macrorhiza, commonly referred to as red prickly pear, is a type of cactus fruit. The Opuntia macrorhiza (OM) fruit is rich in polyphenols and contains a high amount of ascorbic acid and betalains. The fruit peels have demonstrated many biological abilities, including antioxidant, antifungal, and antibacterial activities. Ultrasound probe-assisted extraction (UPAE) is a highly promising method for efficiently extracting valuable molecules from natural sources. The objective of this study is to optimize the parameters of UPAE, including the appropriate solvent, liquid-to-solid ratio, extraction duration, and pulsation level. The aim is to maximize the yield of bioactive compounds (polyphenols, betalains, and ascorbic acid) from OM fruits (pulps and peels) and assess their antioxidant activities using Taguchi design. The optimal extraction conditions through the partial least squares method for OM pulp were determined to be aqueous extraction for 12 min with a liquid-to-solid ratio of 60 mL/g and 48 pulses/min, while for OM peels they were determined to be aqueous extraction for 20 min with a liquid-to-solid ratio of 60 mL/g and a pulsation of 48 pulses/min. The optimum UPAE conditions were compared with the values obtained from the optimum extraction under stirring extraction (STE). Overall, UPAE exhibited higher yields than STE. The obtained total polyphenol content ranged from 10.27 to 13.07 mg gallic acid equivalents/g dry weight, while the betalain content ranged from 974 to 1099 μg/g dry weight. Overall, these fruits demonstrated potential as new components for food and medicinal uses due to their good health effects and lack of toxicity. Full article

The rare metals gallium and germanium are key strategic metals that are widely used in emerging industries. In this work, a novel hydroxamic acid extractant, BGYW, with low toxicity, was used for the selective solvent extraction of Ga ions and Ge ions from Zn, As, Cu, and Al ions in the solution from zinc smelting. The gallium and germanium ions were extracted efficiently under optimized conditions. Gallium ions were preferentially stripped using sulfuric acid, and germanium ions were stripped using an ammonium fluoride solution. Compared with the commercial extractant YW100, the dissolution loss of BGYW was reduced by 10 times. After 15 cycles, the germanium solvent extraction efficiency of BGYW remained at 100%, and the solvent extraction efficiency of gallium was about 98.7%, while the solvent extraction efficiency of both Ga ions and Ge ions using YW100 decreased to 20% after five cycles. This novel solvent extraction system exhibits considerable promise for application in zinc smelting processes for gallium and germanium solvent extraction. Full article

This study aimed to analyze the physicochemical properties and nutritional quality of oil extracted from the camelina seed genotypes NS Zlatka and NS Slatka, grown in Serbia, using both Soxhlet extraction with n-hexane and the cold-pressing technique. Extraction technique did not have an effect on oil yield. Camelina oils exhibited satisfactory physicochemical characteristics, which were influenced by the extraction methods. The oils were rich in polyunsaturated fatty acids, with α-linolenic acid being the most abundant. They were characterized by a balanced ω-6 to ω-3 ratio (0.5), low atherogenicity index and thrombogenicity index values, and a relatively high hypocholesterolemic/hypercholesterolemic ratio. Cold-pressed oils contained significantly higher amounts of α- and γ-tocopherols and showed greater oxidative stability at moderate temperatures, as confirmed by the Schaal oven test. Despite this, their oxidative stability decreased at elevated temperatures (Rancimat test) compared to solvent-extracted oils. Conversely, solvent-extracted oils had higher levels of β-carotene and showed superior resistance to high-temperature conditions. Due to its unique characteristics, nutritional properties, and health-promoting attributes, cold-pressed camelina oil presents significant potential for application in food, nutraceutical, feed, and cosmetic industries. Full article

Background/Objectives: Metabolic profiling of tissue samples via liquid-state nuclear magnetic resonance (NMR) requires the extraction of polar metabolites in a suitable deuterated solvent. Such methods often prioritise metabolite recovery over protein removal due to the relatively low sensitivity of NMR metabolomics and the routine use of methods able to supress residual protein signals. However, residual protein may impact metabolite integrity and the metabolite stability after NMR sample preparation is often overlooked. This study aimed to investigate the effect of residual protein contamination in rodent brain extracts and identify a reproducible extraction method that optimises metabolite recovery while ensuring sample stability. Methods: The performance of acetonitrile/water (50–100% MeCN), methanol/water (50–100% MeOH), and methanol/water/chloroform (MeOH/H₂O/CHCl₃) were assessed for extraction efficiency, reproducibility, residual protein contamination, and metabolite stability up to eight hours post NMR sample preparation. Results: Aspartate and glutamate deuteration were observed in 50% MeCN, 50% MeOH, and 67% MeOH extractions along with the conversion of N-acetyl aspartate to aspartate and acetate in 50% MeCN and 50% MeOH extractions. Both observations correlated with residual protein contamination and, thus, are a result of inadequate protein precipitation, as confirmed by ultrafiltration. MeOH/H₂O/CHCl₃ extraction preserved the stability of these metabolites while maintaining good extraction efficiency and reproducibility. Conclusions: Thus, we recommend MeOH/H₂O/CHCl₃ extraction for untargeted brain NMR metabolic profiling due to its effective protein precipitation and reliable performance. Nonetheless, the performance of detecting metabolites prone to oxidation such as ascorbate and glutathione is not improved by this method. Full article

Deep eutectic solvents (DESs) are mixtures of organic compounds displaying excellent solvent properties while keeping an ecofriendly character. In this study, DESs have been applied to the extraction of phenylpropanoid glycosides from Pedicularis oederi Vahl, successively separated by means of counter-current chromatography. Firstly, the ultrasonic-assisted extraction conditions were optimized by response surface methodology, and the results showed phenylpropanoid glycosides could be well extracted under the optimized extraction conditions with deep eutectic solvents. Then, the sample was separated by counter-current chromatography using ethyl acetate/aqueous solution of choline chloride and glycerol (6:6, v/v) as the solvent system. In about 360 min, four phenylpropanoid glycosides, including 31.6 mg of echinacoside, 65.3 mg of Jionoside A1, 28.9 mg of Forsythoside B, 74.1 mg of verbascoside, and 21.2 mg of kaempferol-3-O-rutinoside were obtained from about 900 mg of the sample. It revealed deep eutectic solvents could be well employed as a green solvent for the extraction and counter-current separation of natural products. Full article

Background: Suk-Saiyasna is a traditional Thai herbal remedy that comprises 12 distinct herbs. Among these, cannabis leaves constitute 12 of the total 78 components in this formulation. This study specifically examines the portion of the cannabis plant, which accounts for approximately 15.8% of the overall herbal composition used in the entire remedy. According to the Thailand Narcotics Act of 2022, the Δ9-tetrahydrocannabinol (Δ9-THC) concentration in herbal extracts must not exceed 0.2% by weight. This study aims to quantify the levels of Δ9-THC and cannabidiol (CBD) in commercial Suk-Saiyasna products. Methodology: This research utilizes Hansen Solubility Parameters (HSPs) to identify the optimal solvent for ultrasonic extraction, thereby maximizing cannabinoid yield. An advanced method was developed employing ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS), compliant with AOAC standards to meet regulatory guidelines. The method validation emphasized specificity, linearity, sensitivity, accuracy, and precision. Results: Dichloromethane was chosen due to its favorable HSP values, enabling highly efficient extraction of Δ9-THC and CBD, achieving recovery rates of over 99.9% after the second extraction. This investigation benefits from the accuracy of the UHPLC-MS/MS technique in quantifying cannabinoids in commercial products, with Δ9-THC concentrations observed between 0.00231% and 0.14218%, and CBD concentrations ranging from 0.00002% to 0.01541%, all remaining below the legal limit. Conclusions: The variability in cannabinoid concentrations among various commercial products highlights the need for standardization in the herbal industry. This finding underscores the critical role of rigorous quality control measures in ensuring the safety and efficacy of cannabis-derived products. Full article

Molecularly imprinted polymers (MIPs) can specifically recognize template molecules in solution with imprinted cavities. Due to their capacity for scalable production, they can be used to isolate target products from natural products for industrial production in the fields of pharmaceuticals and food. In this study, magnetic single-template molecularly imprinted polymers (St-MIPs) instead of magnetic multi-template molecularly imprinted polymers (Mt-MIPs) were prepared by surface imprinting using Schizandrol A as a template molecule and deep eutectic solvent (DES) as a functional monomer, combined with solid-phase extraction (SPE) for the adsorption and separation of Schizandrol A, Schisantherin A, Schizandrin A, and Schizandrin B from Schisandra chinensis (Turcz.) Baill. (S. chinensis) fruits extracts. The synthesized MIPs were characterized by FT-IR, TEM, SEM, TG, XRD and VSM, and their adsorption properties were also evaluated. MIPs can specifically recognize the template molecules with high reusability. The purity of the total S. chinensis lignans after SPE was 74.05%, among which that of Schizandrol A, Schisantherin A, Schizandrin A, and Schizandrin B was 33.38%, 8.69%, 16.33% and 15.67%, respectively. Moreover, the one-step synthesis of carrier was easy to operate. And St-MIPs reduced the production cost compared with Mt-MIPs. This study provides a new idea for natural product separation by molecular imprinting technology (MIT). Full article

Contamination of marine ecosystems by pharmaceutically active compounds (PhACs) deserves more research since their environmental fate differs from that observed in freshwater systems. However, knowledge remains scarce, especially in semi-arid coastal regions of the Global South. This study investigates the occurrence and distribution of caffeine, carbamazepine, ciprofloxacin, and sulfamethoxazole in sediments from the La Paz lagoon, a coastal system in a semi-arid region of Mexico with inverse estuarine conditions. Samples of superficial sediments (0–5 cm depth) were collected from 18 sampling points distributed through the lagoon, encompassing sites heavily polluted by discharges of municipal sewage and 3 potentially pristine sites far from the urban and peri-urban zones. Also, a 25 cm length sediment core was taken and divided into 1 cm sub-samples to determine the deposition of target PhACs in the sediment bed through time. The extraction of the target PhACs was performed through the accelerated solvent extraction (ASE) technique and quantification was achieved using a validated HPLC-MS/MS analytical method. The concentration of caffeine, carbamazepine, ciprofloxacin, and sulfamethoxazole in superficial sediment oscillated in the range of 1 to 45 ng g⁻¹ (dry weight). The highest mass fraction of target PhACs was detected in sites impacted by wastewater discharges. The caffeine-to-carbamazepine ratio was determined for the first time in marine sediments impacted by wastewater discharges, resulting in values from 4.2 to 9.12. Analysis of the 25 cm length sediment core revealed a high dispersion of caffeine, which was attributed to high water solubility, while antibiotics were predominantly detected in the upper 20 cm of the core. Risk quotients were calculated, observing low risk for caffeine, carbamazepine, and ciprofloxacin, while sulfamethoxazole presented high risk in all the sampling points. PhACs are retained in superficial sediments from a lagoon impacted by wastewater discharges, and the level of impact depends on the properties of the compounds and the TOC content in sediments. Risk assessments should be performed in the future considering the combination of pharmaceuticals and byproducts in marine sediments. This research emphasizes the importance of sewage management in preserving marine ecosystems in semi-arid regions in the Global South. Full article