High-performance Liquid Chromatography-ultraviolet Research Articles

Rapid and efficient high-performance liquid chromatography-ultraviolet determination of total amino acids in protein isolates by ultrasound-assisted acid hydrolysis

This study presents the optimization and validation of an ultrasound-assisted acid method for the HPLC-UV determination of amino acids in plant-based proteins. The research focuses on enhancing hydrolysis efficiency and reducing environmental impact. Ultrasound treatment significantly accelerated hydrolysis by creating cavitation, which increases local pressure and temperature, leading to faster reaction rates. The optimal condition was a 30-minute treatment at 90 °C with 6 M hydrochloric acid. The 9-fluorenylmethyloxycarbonyl chloride derivatization was best performed at pH 9.0 using borate buffer, ethanol as the organic solvent, and a 5-minute derivatization time with a 5 mM concentration. The method’s analytical performance, validated according to FDA guidelines, showed excellent selectivity, specificity, linearity (r2 > 0.999), accuracy (recovery between 80–118 %), and precision (RSD<10.9). The analysis of 15 plant-based proteins revealed distinct amino acid profiles. Compared to traditional acid hydrolysis methods, the ultrasound-assisted approach demonstrated no significant difference in results (p-value > 0.05), confirming its reliability. The optimized ultrasound-assisted method is a reliable and efficient alternative for amino acid analysis, offering significant cost and time savings while maintaining high analytical performance. These findings are crucial for nutritional planning and developing functional foods to improve health outcomes.

Development and Validation of a High-Performance Liquid Chromatography-Ultraviolet Spectrometry Method for Ampicillin and its Application in Routine Therapeutic Drug Monitoring of Intensive Care Patients.

Ampicillin/sulbactam, a combination of a β-lactam and β-lactamase inhibitor, is widely used in clinical settings. However, therapeutic drug monitoring (TDM) of ampicillin is not commonly performed, particularly in intensive care units (ICUs). The purpose of this study was to develop and validate a rapid and cost-effective high-performance liquid chromatography (HPLC)-ultraviolet spectrometry method to quantify ampicillin in human serum and evaluate its clinical application in ICU patients. Sample cleanup included a protein precipitation protocol, followed by chromatographic separation on a C18 reverse-phase HPLC column within 12.5 minutes using gradient elution of the mobile phase. The assay was validated according to the German Society of Toxicology and Forensic Chemistry criteria. Clinical applications involved the retrospective analysis of TDM data from ICU patients receiving continuous infusion of ampicillin/sulbactam, including the attainment of target ranges and individual predicted and observed pharmacokinetics. The method was robust, with linear relations between the peak area responses and drug concentrations in the range of 2-128 mg/L. The coefficient of variation for precision and the bias for accuracy (both interday and intraday) were less than 10%. Clinical application revealed variable pharmacokinetics of ampicillin in ICU patients (clearance of 0.5-31.2 L/h). TDM-guided dose adjustments achieved good therapeutic drug exposure, with 92.9% of the samples being within the optimal (16-32 mg/L) or quasioptimal (8-48 mg/L) range. This method provides a practical solution for the routine TDM of ampicillin, facilitating individualized dosing strategies to ensure adequate therapeutic drug exposure. Given its simplicity, cost-effectiveness, and clinical relevance, HPLC-ultraviolet spectrometry holds promise for broad implementation in hospital pharmacies and clinical laboratories.

Preparation and evaluation of Fe3O4@C@NiCo-LDH@CDs composites for magnetic solid-phase extraction of trace endocrine disruptors.

The widespread use of endocrine disruptors (EDPs) has certain potential hazards to organisms and environments, and it is particularly important to develop effective pretreatment methods before detection of EDPs in complex samples. In this work, a novel magnetic nanocomposite decorated with layered double hydroxides (LDHs) and carbon dots (CDs) was designed and prepared for magnetic solid-phase extraction (MSPE) of EDPs (bisphenol S, bisphenol F, bisphenol A, bisphenol AF, diethylstilbestrol and 4-cumylphenol) combined with high-performance liquid chromatography-ultraviolet (HPLC-UV) detection. The prepared composites were characterized by field emission scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS), and the adsorption mechanism towards these EDPs might be mainly based on hydrogen bonds and π-π conjugation. Under the optimized conditions, the proposed method showed limits of detection within 0.05-0.50 μg L-1 and limits of quantitation within 0.2-2.0 μg L-1, and good linearity (R2 ≥ 0.9975) was presented in the range of 0.2-200 μg L-1. Finally, the Fe3O4@C@NiCo-LDH@CDs composite-based MSPE-HPLC-UV method was applied for enrichment and determination of EDPs in water, milk, and tea beverage samples with recoveries in the range of 81.2-119.8% and relative standard deviations below 9.7%.

Extraction and detection of sulfonamide antibiotics in milk using magnetic solid-phase adsorbent based on molecular mechanics and DFT calculations

Based on the foundation of calculations in molecular mechanics and density functional theory (DFT) for in-depth mechanistic studies, this paper proposes the sample multi-residue analysis method of five common sulfonamide antibiotics (SAs) in milk. Fe3O4 nanoparticles modified magnetic graphene oxide nanoribbons (Mag-GONRs) with superior dispersibility and dispersion stability, were developed and firstly utilized to rapidly extract residual SAs from milk. Therefore, various SAs in complex samples could be simultaneously determined solely by high performance liquid chromatography-ultraviolet detector (HPLC-UV) without the need for complicated pretreatment processes. In order to obtain satisfactory extraction efficiency, indispensable investigation and optimization were conducted on some parameters influencing the extraction efficiency. And the extracted SAs were determined by. Good linearity for all analytes was achieved with appropriate correlation coefficients (R2 higher than 0.9978). The limits of detection ranged from 0.060 to 0.075 ng·mL−1. Recoveries of the sulfonamides in spiked milk samples were between 79.6 % and 114.6 %, with relative standard deviations within 12 %. Interestingly, with the assistant of computational chemistry, the efficient extraction of Mag-GONRs onto SAs has been validated at the molecular and quantum levels, further elucidating the adsorption mechanism based on non-covalent interactions. In the context of theoretical research and experimental results mutually supporting each other, a practical detection method with actual application value has been proposed in monitoring the residual sulfonamides in milk by the common devices.

In-tube solid-phase microextraction of polycyclic aromatic hydrocarbons from refinery water samples using UiO-66/polyacrylonitrile electrospun nanofibers followed by high-performance liquid chromatography-ultraviolet detection.

A simple and quick fiber-in-tube solid-phase microextraction (FIT-SPME) was introduced for the extraction and determination of nine polycyclic aromatic hydrocarbons followed by a high-performance liquid chromatography-ultraviolet detector in refinery water samples. For this purpose, a water-resistant metal-organic framework with a high surface area called UiO-66 has been applied in the form of an electrospun coating on stainless steel wires. After that, all the fibers were packed in the lumen of a stainless-steel tube to make the extraction phase. Both one variable at a time and experimental design methods have been used to optimize effective parameters on FIT-SPME. Under optimum conditions, the method demonstrated good linearity between 0.5 and 1000.0µg/L with a coefficient of determination greater than 0.9906. Furthermore, the limits of detection values ranged from 0.2 to 1.5µg/L. The intra-day and inter-day relative standard deviations were<8.4% and<9.7%, respectively. Lastly, the proposed method was applied to extract and determine analytes in four refinery water samples as well as surface water containing high total dissolved solids, and well waters where satisfactory results have been obtained.

Determination of anamorelin concentration in human plasma using a simple high-performance liquid chromatography-ultraviolet detection method.

Anamorelin, a non-peptide ghrelin analog and growth hormone secretagogue, is a novel oral drug used to treat cancer cachexia. Patients with cancer cachexia frequently use several drugs and anamorelin is a substrate of cytochrome P450 (CYP) 3A4; therefore, drug-drug interactions with CYP3A4 inhibitors and inducers pose a clinical problem. In this study, we aimed to determine the concentration of anamorelin in human plasma using a simple high-performance liquid chromatography-ultraviolet (HPLC-UV)-based method. The analysis involved extracting a 200-μL plasma sample and protein precipitation using solid-phase extraction. Anamorelin was isocratically separated using a mobile phase consisting of 0.5% potassium dihydrogen phosphate (pH 4.5) and acetonitrile (61:39, v/v) on a Capcell Pack C18 MG II column (250 mm × 4.6 mm) at a flow rate of 1.0 mL/min and monitored at a detection wavelength of 220 nm. The calibration curve was linear within a plasma concentration range of 12.5-1,500 ng/mL, with a coefficient of determination of 0.9999. The intra- and inter-day coefficients of variation were 0.37-6.71% and 2.05-4.77%, respectively. The accuracy of the assay and recovery were 85.25-112.94% and > 86.58%, respectively. This proposed HPLC-UV method is simple and can be applied in clinical settings.

Deciphering the anti-diabetic potential of Dipsacus asperoides root: Identification of active compounds and quality assessment

The plant Dipsacus asperoides C. Y. Cheng et T. M. A., has been traditionally utilized as a medicinal plant in China due to its roots known as “Dipsaci Radix”. It is suggested that Dipsaci Radix exhibits antihyperglycemic, hypolipidemic, and antioxidant properties, along with down-regulating effects on advanced glycation end-products (AGEs) formation. However, there are currently no reliable reports on the effective components derived from Dipsaci Radix for anti-diabetes. In this study, the methanol extract and its corresponding ethyl acetate (EA) fraction of Dipsaci Radix were investigated as potential natural sources of antidiabetic agents and antioxidants by in vivo methods. The existence of phenolic components in extract and fraction enhances their antioxidant and antidiabetic properties. This is evidenced by the fact that all isolated phenolic compounds exhibited such properties, with half of them (Compound 2, 4, 5, 8, 10) displaying multidirectional inhibitory effects. Quality evaluation of these active components using high performance liquid chromatography-ultraviolet (HPLC-UV) technology combined with grey relational analysis provides further information regarding the spectrum-effect relationship between active components and their activities. Among them, the presence of the active ingredient “5-O-caffeoylquinic acid” significantly contributes to the antidiabetic and antioxidant properties of Dipsaci Radix. This holds promising applications in traditional health products and cosmeceuticals.

A method validation of determination of melamine in marketed infant formula and milk powder of Iran

Melamine is a recognized food contaminant that can arise incidentally or intentionally in specific categories of food. This study aimed to validate the melamine detection and quantification in infant formula and milk powders and also analyzed 40 samples consist of infant formula and milk powders from commercially available food products, from different geographic regions of Iran. The approximate content of melamine in samples was measured by High-performance liquid chromatography-ultra violet (HPLC–UV) system. A calibration curve (R2 = 0.9925) was established for detection of melamine in the range of 0.1–1.2 μg mL−1. Limit of quantification and limit of detection were 1 μg mL−1 and 3 μg mL−1, respectively. The presence of melamine in infant formula and milk powdered was investigated and it was observed that the amount of melamine in samples of infant formulas and milk powders was 0.001–0.095 mg kg−1 and 0.001–0.004 mg kg−1, respectively. These values were found to be within the prescribed limits by the European Union and Codex Alimentarius Commission legislation. It is important to note that the consumption of these dairy products, which contain low content of melamine, does not pose any significant threat to consumer health. Furthermore, the results of the risk assessment confirmed this issue.

Green determination of glucocorticoids in water environment based on novel polydopamine coated iron tetroxide via magnetic dispersive solid phase microextraction

As the potential risks on human and aquatic animal exposed to the glucocorticoids in environment, it is essential to detect anti-epidemic pharmaceutical in real water samples. In this work, a core-shell shape, magnetic suspension particle sorbents of Fe3O4@oleic acid@polydopamine (Fe3O4@OA@PDA) were synthesized for magnetic dispersive solid phase microextraction (MDSPME), which possessed considerable dispersibility in water samples and extracted three glucocorticoids through hydrogen bonding with high detection sensitivity. The adsorption process of MDSPME was investigated by thermodynamic and kinetic theory, which demonstrated that the kinetic processes of adsorption were in accordance with the quasi second order kinetic model, and the adsorption isotherm was in accordance with the Freundich model. Combined with high performance liquid chromatography-Ultraviolet spectrophotometer detector, the proposed method had a linear range of 5–200 μg/L with an ultra-low detection limit down to 0.5–1.1 μg/L. The Green Analytical Greenness Metric (AGREE) software was employed to evaluate the greenness of the analytical method. This work presented an effective strategy for creating ultrasensitive and cost-effective probe for detection in anti-epidemic drugs.

Aflatoxins, fumonisins, citrinin, and zearalenone contents and health risk estimates in bee products in Turkey

Food contamination is an important global food safety issue. This study aimed to detect aflatoxins (AFB1, AFB2, AFG1, AFG2), fumonisins (FB1, FB2), citrinin (CIT), and zearalenone (ZEA) in four bee product groups (honey, royal jelly, bee pollen, propolis) in Turkey. Additionally, exposure and risk assessments were made for mycotoxins detected in these products. Mycotoxin analyzes in bee products were carried out by high-performance liquid chromatography-ultraviolet (HPLC-UV) and liquid chromatography-tandem mass spectrometry (LC/MS-MS) methods. The most frequently detected mycotoxins in all bee products were ZEA (37.5%) and AFB2 (36.6%). The analysis showed that the average concentrations of FB2 (2.091 μg/kg), AFB1 (0.595 μg/kg), and ZEA (0.009 μg/kg) in all bee products were above the detection limit levels, while the levels of AFB2, AFG1, AFG2, FB1, and CIT were below the limit of detection. When comparing bee products, it was found that honey samples were more exposed to AFB2 and FB1, bee pollen to FB1, propolis to AFB2, and royal jelly to ZEA contamination. AFG1 and CIT were not detected in propolis and bee pollen, respectively. All mycotoxins analyzed in the study pose no health risks when bee products are consumed daily.

Determination of the Chemical Content of Shilajit in Terms of Ten Different Polyphenolic Compounds by UAE Method and HPLC Analysis

Shilajit (Mumio) is a complex of natural bioactive compounds that has historically been used as a therapeutic cream for many skin diseases and is suitable in traditional medicine for diseases such as diabetes, Alzheimer's and cancer. In this study, to determine the polyphenolic content of Shilajit, extracts obtained at 45 degrees were analyzed by High Performance Liquid Chromatography-Ultraviolet (HPLC-UV) for the quantitative analysis of ten different polyphenolic compounds. As a result of the experimental study, 28.99±1.23 µg/g routine, 25.47±1.67 µg/g ferulic acid, 41.49±0.41 µg/g resveratrol and 532.19±8.21 µg/g taxifolin was obtained. This study's results will significantly contribute to sectors such as the extraction of bioactive substances, scaling studies, and their use as food supplements and pharmaceutical applications.

Alien species water hyacinth realizes waste into treasure: The preparation of biomass sorbent to determine benzoylurea insecticides in tea products.

A fast and effective analytical method with biomass solid-phase microextraction sorbent combined with a high-performance liquid chromatography-ultraviolet detector was proposed for the determination of benzoylurea (BU) insecticides in tea products. The novel sorbent was prepared by activating and then carbonizing water hyacinth with a fast growth rate and low application value as raw material and showed a high specific surface area and multiple interactions with analytes, such as electrostatic action, hydrogen bonding, and π-π conjugation. After optimizing the three most important extraction parameters (pH [X1], sample loading rate [X2], and solution volume [X3]) by Box-Behnken design, the as-established analytical method showed good extraction performance: excellent recovery (80.13%-106.66%) and wide linear range (1-400µg/L) with a determination coefficient of 0.9992-0.9999, a low limit of detection of 0.02-0.1µg/L and the satisfactory practical application results in tea products. All these indicate that the water hyacinth-derived material has the potential as a solid-phase extraction sorbent for the detection and removal of BU insecticides from tea products, and at the same time, it can also achieve the effect of rational use of biological resources, maintaining ecological balance, turning waste into treasure, and achieving industrial production.

Simultaneous determination of six catechins and caffeine in tea and wine using salting-out assisted liquid-liquid extraction and high-performance liquid chromatography with ultraviolet detection.

Catechins, renowned for their antioxidant properties and health benefits, are commonly present in beverages, particularly tea and wine. An efficient and cost-effective salting-out assisted liquid-liquid extraction (SALLE) method has been developed and validated for the simultaneous determination of six catechins and caffeine in tea and wine samples using high-performance liquid chromatography-ultraviolet (HPLC-UV). This method demonstrates outstanding performance: linearity (1-120µg/mL, r2>0.999), accuracy (96.5%-103.4% recovery), and precision (≤14.7% relative standard deviation), meeting validation requirements set by the US Food and Drug Administration. The reduced sample size (0.1g) minimizes matrix interferences and costs without compromising sensitivity. All analytes were detected in Camellia sinensis teas, with green tea displaying the highest total catechin content (47.5-100.1mg/mL), followed by white and black teas. Analysis of wine samples reveals the presence of catechin in all red and white wines, and epigallocatechin gallate in all red wine samples, highlighting the impact of winemaking processes on catechin content. The SALLE-HPLC-UV approach represents a green alternative by eliminating organic waste, surpassing conventional dilution methods in specificity and sensitivity for catechin determination. AGREEprep assessment emphasizes the strengths of the SALLE procedure, including material reusability, throughput efficiency, minimal sample requirements, low energy consumption, and the absence of organic waste generation.

Study on determination methods and analysis of micronutrients in take-away meals

To comprehensively analyze the trace nutrient contents in take-away meals, the simultaneous detection method of common vitamins in take-away meals were explored based on the samples&apos; matrix, and the content of trace nutrients in take-away meals was analyzed combined with inductively coupled plasma-mass spectrometry(ICP-MS) detection of common elements. Fifty-seven take-away meals were collected randomly and analyzed. Vitamins were determined by high performance liquid chromatography-ultraviolet detector tandem fluorescence detector after pretreatment of samples including enzymatic digestion, hydrolysis and extraction. The separation was performed on a C_(18) column(250 mm×4.6 mm, 5 μm) with ion-pair acid reagents as the mobile phase for water-soluble vitamins and methanol for fat-soluble vitamins. Vitamin B_1, vitamin B_2, nicotinic acid, nicotinamide and vitamin A were detected by ultraviolet detector(UVD), while vitamin B_6 and E by fluorescence detector(FLD). Elemental analysis of calcium, magnesium, sodium, potassium, zinc, selenium and copper in the take-away meals was carried out according to GB 5009.268-2016 by ICP-MS to comprehensively evaluate the contents of micronutrients. Through optimization of chromatography and sample pretreatment conditions, the sensitivity of the established detection method can meet the needs of micronutrient evaluation with the detection limits and quantification limits of vitamins in the range of 0.002-0.098 mg/100 g and 0.007-0.327 mg/100 g, respectively. Good precision was obtained(&lt;10%). The spiked recovery rates were 80.5%-103.8%(n=6). The result showed that the contents of micronutrients in take-away meals were generally low. The detection rates of vitamins ranged from 21.1% to 98.2%. The proposed method is simple and sensitive, and the contents of vitamins and elements determined were low in the collected take-away meals.

Dispersive liquid–liquid microextraction based on deep eutectic solvent followed by high-performance liquid chromatography-ultraviolet for imidacloprid, hexythiazox, and fenpyroximate determination: Experimental design approach

Dispersive liquid–liquid microextraction (DLLME) of three insecticides, including imidacloprid (I), hexythiazox (H), and fenpyroximate (F), was performed as an efficient method for separation and preconcentration using a deep eutectic choline chloride-acetic acid solvent (DES) followed by determination by high-performance liquid chromatography-ultraviolet (HPLC-UV). The experimental design approach (central composite design) was used to optimize the effective parameters. According to the results, the addition of salt had no significant effect on extraction among the four parameters studied, including pH, DES volume (dispersive solvent), salt concentration, and chloroform volume. The optimized conditions in the DES-DLLME-HPLC-UV method were pH = 6.00, 100 µL DES, and 138 µL chloroform. Under optimized conditions, a wide linear range of 1.00 × 10−3-20.00 µg mL−1 was obtained for three insecticides. The enhancement factors were 11.22, 58.04, and 39.65 and the limit of detection of 3.00 × 10−4, 2.00 × 10−4, and 2.00 × 10−4 µg mL−1, and the limit of quantification of 9.00 × 10−4, 8.00 × 10−4, and 6.00 × 10−4 µg mL−1 were also determined for imidacloprid, hexythiazox, and fenpyroximate, respectively. The presence of other components including benomyl, dimethoate, mancozeb, captan, thiodicarb, carbendazim, and oxyfluorfen, showed no significant interference effect on the determination of three insecticides up to 50-fold. The method is eco-friendly benign, sensitive, precise, and straightforward as shown by the results.

High-performance liquid chromatography (HPLC) as a means of assessing the presence of uric acid in archeological human remains: Challenges and future directions.

This research aimed to replicate the Swinson, D., Snaith, J., Buckberry, J., & Brickley, M. (2010). High performance liquid chromatography (HPLC) in the investigation of gout in paleopathology. International Journal of Osteoarchaeology, 20, 135-143. https://doi.org/10.1002/oa.1009 method for detecting uric acid in archeological human remains to investigate gout in past populations and to improve the original High Performance Liquid Chromatography-ultraviolet (HPLC-UV) method by using HPLC-mass spectrometry (HPLC-MS), a more sensitive, compound-specific detection method. We used reference samples of uric acid to create a dilution series to assess the limits of quantification and detection. Samples from individuals with and without gout lesions were taken from foot bones and ribs from the English cemeteries of Tanyard, Hickleton, Gloucester, and Lincoln. We could not replicate the results of Swinson and colleagues using HPLC-UV. Tests using a dilution series of uric acid showed HPLC-MS was approximately 100× more sensitive than HPLC-UV, with the additional benefit of being compound specific. A newly developed hydrophilic interaction chromatography (HILIC) method improved retention characteristics. Fourteen samples from eight individuals, five with skeletal lesions consistent with gout, were analyzed with the final method. None showed evidence of uric acid despite the newly developed method's improved sensitivity and specificity. The lack of detectable uric acid extracted from these samples suggests that (1) urate crystals were not present in any of the bone samples, regardless of gout status; (2) urate crystals did not survive these specific archeological conditions; or (3) the concentration of uric acid in our bone extracts was low, and thus larger samples would be required.

Simultaneous high-performance liquid chromatography analysis of anthraquinones in sicklepod sprouts with α-glucosidase inhibitory activity.

Sicklepod [Cassia obtusifolia L. syn Senna obtusifolia (L.) H.S. Irwin & Barneby, Fabaceae] sprouts are promising ingredients with health-promoting benefits. Notwithstanding, the pharmacologically active compounds in sicklepod sprouts have not been studied or analysed in detail. This study aimed to isolate and structurally identify phytochemicals showing α-glucosidase inhibitory activity in sicklepod sprouts and simultaneously quantify the compounds in the sprouts to determine the optimal cultivation method and germination time to maximise active compounds. A simultaneous high-performance liquid chromatography-ultraviolet (HPLC-UV) method with high sensitivity and accuracy was developed and used to analyse time-dependent changes in anthraquinone content during sicklepod germination. Thirteen anthraquinones were isolated and identified, of which six-chrysoobtusin, emodin, 1-O-methyl-2-methoxychrysophanol, 7-O-methylobtusin, chrysophanol, and physcion-showed moderate α-glucosidase inhibitory activity. The maximum content of anthraquinones in a sprout was observed on Day 5 under both light and dark conditions. The findings of this study revealed that sicklepod sprouts which are promising functional food materials contain a variety of anthraquinones.

Phytochemical characterization, antioxidant, and antimicrobial activities of the Ayurvedic polyherbal formulation Mentone

Introduction: Polyherbalism is extensively practiced in traditional medicine and constitutes complementary and alternative medicine (CAM). Greater therapeutic efficacy ensues from the synergistic effects of constituents mediated by pharmacodynamic and pharmacokinetic interactions and safety at higher dosages. Very few studies exist on mechanistics, despite rampant polyherbal use. Mentone tablet is a polyherbal constituting equal components of Centella asiatica (L.) Urban, Convolvulus pluricaulis Choisy, Glycyrrhiza glabra L., and Tinospora cordifolia (Willd.) Miers ex Hook. F. and Thomson. Materials and Methods: Proximate and phytochemical analysis followed by quantification of polyphenolics was carried out. Asiatic acid, berberine, betaine, and glycyrrhizin were characterized using ultraviolet–high-performance liquid chromatography (UV-HPLC). Antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) quenching activity, ferric reducing ability of plasma (FRAP) assay, and hydrogen peroxide (H2O2) scavenging activity. Antimicrobial activity was determined by Kirby–Bauer disc diffusion microbial susceptibility test followed by minimum inhibitory concentration (MIC) method. Results: Aqueous extraction using Soxhlet generated maximum yield. Proximate analysis yielded 52.96% ash, pH ranged from 5.75 to 5.76, and 5% moisture content. Qualitative analysis revealed the presence of inorganic substances and phytochemicals: saponins, reducing sugars, terpenoids, starch, glycosides, and triterpenoids. Phenols were higher in aqueous, while flavonoids and tannins were higher in ethanolic extracts. HPLC revealed the presence of glycyrrhizin and asiatic acid. Mentone extracts at 100 µg/mL showed the highest antioxidant activity in DPPH, FRAP assays, and H2O2 radical scavenging. Ethanolic extracts above 50 mg/mL demonstrated antimicrobial activity against Staphylococcus aureus ATCC 25923 and Klebsiella pneumoniae ATCC 700603. Conclusion: Mentone contains phytochemicals with antioxidant and antimicrobial activities. With active constituents such as asiatic acid and glycyrrhizin, Mentone could constitute a CAM for oxidative stress-induced diseases, including neurodegeneration.

Application of solid-phase extraction materials from ion liquids for the analysis of carbamate pesticide

In this study, ionic liquid immobilised onto silica gel material SiO2-(CH2)3-N(Oct)3Br was successfully synthesised and characterised by Fourier-transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). This material was applied as the stationary phase of solid-phase extraction for the enrichment of trace amounts of carbamate pesticides in water. The cartridge was eluted with 5 ml of acetonitrile (ACN), blow-dried with nitrogen gas, and re-dissolved in ACN:H2O (40:60, v/v) and analysed by high-performance liquid chromatography - ultraviolet (HPLC-UV) at 210 and 245 nm. Within this process, elution of the cartridge with 5 ml of acetonitrile (ACN) was followed by nitrogen gas blow-drying and subsequent re-dissolution in ACN:H2O (40:60, v/v), culminating in analysis by HPLC-UV at 210 and 245 nm. Optimisation of conditions facilitated the analysis of carbamate pesticides, with the limit of quantitation (LOQ)ranging from 0.36-2.00 μg/l for tap water and 0.4-3.5 μg/l for river water. Furthermore, the method exhibited favourable repeatability, with a relative standard deviation (RSD) of less than 10%, thereby meeting the Association of Official Analytical Collaboration (AOAC) standards.

Easy and fast synthesis of MnCo-LDH yolk-shell spheres porous composites applied electrospinning nanofibers highly effective for extracting triazole fungicides

Today, the wide utilization of triazole fungicides due to environmental damage and its side effects has raised global concern. Thus, in this investigation, polyacrylonitrile/MnCo-layered double hydroxides nanofiber was synthesized and applied as an effective and novel adsorbent at thin-film solid-phase micro-extraction technique for the quick and concurrent extraction of five triazole fungicides in fruit and vegetable samples before quantitative analysis by high-performance liquid chromatography-ultraviolet. The incorporation of MnCo-layered double hydroxides with porous structure and abundant functional groups in a polymer medium improves the extraction efficiency of nanofibers owing to hydrogen bonding and π-π interactions formed between analytes and synthesized nano-adsorbent. Various important elements that affect the extraction efficiency of the intended analytes were optimized using a time-variable approach. Under the optimum conditions, the limit of detection and quantification range from 0.1 to 0.15 and 0.3–0.5 ng mL−1, respectively.