High-performance Liquid Chromatography Research Articles

Electrochemical Determination of 2,4-Dichlorophenol in Industrial Wastewater Using Bimetallic Metal-Organic Framework (MOF) Functionalized Graphene Oxide (GO) and Cetyltrimethylammonium Bromide (CTAB)

This study reports a sensor using a bimetallic metal-organic framework combined with 1,3,5-benzenetricarboxylic acid (BTC) (ZrCuBTC MOFs) functionalized graphene oxide (GO) and cetyltrimethylammonium bromide (CTAB) to determine the concentration of 2,4-dichlorophenol (2,4-DCP) in industrial wastewater. ZrCuBTC/GO was cast on a bare glassy carbon electrode followed by CTAB for analyte adsorption to produce the CTAB/ZrCuBTC/GO@GCE. The ZrCuBTC/GO was characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD), and N2 adsorption–desorption analysis. The electrochemical properties of these materials and 2,4-DCP on the CTAB/ZrCuBTC/GO were investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV). The ZrCuBTC/GO had particle sizes from 20 to 40 nm, a pore diameter of 2.71 nm, a pore volume of 0.793 cm3 g−1, and a surface area of 1227 m2 g−1. Under the optimized conditions, the sensor had excellent electrocatalytic activity and high selectivity for 2,4-DCP. Linear ranges from 0.01 to 0.1, 0.1 to 1.5, and 1.5 to 30 µM were obtained with a low detection limit of 8 nM and excellent reproducibility of 2.71%. Wastewater before and after spiking was analyzed using the sensor and high-performance liquid chromatography (HPLC). The results were comparable with recoveries from 94.9 to 110.3 and 88.6 to 100.2%, respectively. Therefore the developed approach was suitable for the determination of 2,4-DCP in environmental samples.

Development of a new high performance liquid chromatography-fluorescence detection (HPLC-FL) method for the determination of biogenic amines in frozen fish sold in markets

<p class="MsoNormal" style="text-align:justify;line-height:200%"><span lang="EN-GB" style="font-size:12.0pt;line-height:200%;font-family:"Times New Roman","serif"; mso-fareast-font-family:"Times New Roman";mso-ansi-language:EN-GB;mso-fareast-language: ZH-CN">It is now possible to measure the biogenic amines histamine, tryptamine, putrescine, cadaverine, spermidine, spermine, and tyramine in an easy, accurate, and selective manner. Dansyl chloride was used to purify the analytes, and high-performance liquid chromatography with detection of fluorescence was utilized for separating them. This is a useful method for identifying and measuring biogenic amines in fish samples in a selective manner. The C18 (250 mm × 4.6 mm × 5 μm) column was used for the separation by chromatography. A mobile phase comprising acetonitrile and phosphate buffer (pH=4.0) (60:40, v/v) was used at an average flow rate of 0.9 mL/min. The technique relied on utilizing fluorescence detection to determine the derivative </span><span style="font-size:12.0pt;line-height:200%;font-family: "Times New Roman","serif"">(λ<sub>ex</sub>=230 nm, λ<sub>em</sub>= 350 nm) </span><span lang="EN-GB" style="font-size:12.0pt;line-height:200%;font-family:"Times New Roman","serif"; mso-fareast-font-family:"Times New Roman";mso-ansi-language:EN-GB;mso-fareast-language: ZH-CN">The suggested method's linearity was examined between 0.01 and 50 μg/mL </span><span style="font-size:12.0pt;line-height:200%;font-family:"Times New Roman","serif"">(r<sup>2</sup>=0.9996). </span><span lang="EN-GB" style="font-size:12.0pt;line-height:200%;font-family: "Times New Roman","serif";mso-fareast-font-family:"Times New Roman";mso-ansi-language: EN-GB;mso-fareast-language:ZH-CN">In compliance with ICH criteria, the method was verified with respect to accuracy, precision, repeatability, specifity, robustness, and detection and quantification limitations. The suggested technique has been effective in tracking the production of biogenic amines in specimens of fish that can be purchased frozen in marketplaces. It was discovered that the recommended approach worked well for routinely analyzing fish sample biogenic amine analyses.<o:p></o:p></span></p>

Innovative Microencapsulation of Polymyxin B for Enhanced Antimicrobial Efficacy via Coated Spray Drying.

This study aims to develop an innovative microencapsulation method for coated Polymyxin B, utilizing various polysaccharides such as hydroxypropyl β-cyclodextrin, alginate, and chitosan, implemented through a three-fluid nozzle (3FN) spray drying process. High-performance liquid chromatography (HPLC) analysis revealed that formulations with a high ratio of sugar cage, hydroxypropyl β-cyclodextrin (HPβCD), and sodium alginate (coded as ALGHCDHPLPM) resulted in a notable 16-fold increase in Polymyxin B recovery compared to chitosan microparticles. Morphological assessments using fluorescence labeling confirmed successful microparticle formation with core/shell structures. Alginate-based formulations exhibited distinct layers, while chitosan formulations showed uniform fluorescence throughout the microparticles. Focused beam reflectance and histograms from fluorescence microscopic measurements provided insights into physical size analysis, indicating consistent sizes of 6.8 ± 1.2 μm. Fourier-transform infrared (FTIR) spectra unveiled hydrogen bonding between Polymyxin B and other components within the microparticle structures. The drug release study showed sodium alginate's sustained release capability, reaching 26 ± 3% compared to 94 ± 3% from the free solution at the 24 h time point. Furthermore, the antimicrobial properties of the prepared microparticles against two Gram-negative bacteria, Escherichia coli and Pseudomonas aeruginosa, were investigated. The influence of various key excipients on the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values was evaluated. Results demonstrated effective bactericidal effects of ALGHCDHPLPM against both E. coli and P. aeruginosa. Additionally, the antibiofilm assay highlighted the potential efficacy of ALGHCDHPLPM against the biofilm viability of E. coli and P. aeruginosa, with concentrations ranging from 3.9 to 500 μg/m. This signifies a significant advancement in antimicrobial drug delivery systems, promising improved precision and efficacy in combating bacterial infections.

Chemical composition, cytotoxic potential and antioxidant properties of Punica granatum peel extract

Purpose: To evaluate the antioxidant activity of pomegranate peel extract and its effects on the survival of colorectal cancer cells (Caco-2) and kidney cells (HEK293). Methods: An ethanol extract was prepared from the outer layer of pomegranate peels. The chemical composition of the extract was examined using high-performance liquid chromatography with diodearray detection (HPLC-DAD) and liquid chromatography with tandem mass spectrometry (LC-MS-MS). Antioxidant activity was determined using DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'- azinobis(3-ethylbenzothiazoline-6-sulfonic acid)) assays. Cytotoxicity was tested against Caco-2 colorectal cancer cells and HEK293 normal kidney cells using MTT assay. Results: The pomegranate peel extract was rich in phenolic compounds and demonstrated significant antioxidant activity, with IC50 values comparable to Trolox in DPPH and ABTS assays. The extract exhibited selective and concentration-dependent cytotoxicity against Caco-2 cells, with an EC50 of 121.05 ± 13.12 µg/mL, while showing minimal toxicity towards HEK293 cells. Conclusion: Pomegranate peel extract's high phenolic content and potent antioxidant properties highlight its potential as a therapeutic agent against colorectal cancer. The findings suggest that this extract could serve as a viable, natural alternative with reduced toxicity for colorectal cancer treatment.

Phytohormonal dynamics in the abscission zone of Korla fragrant pear during calyx abscission: a visual study.

Phytohormones play a crucial role in regulating the abscission of plant organs and tissues. In this study, the ultrastructure of the sepals of Korla fragrant pears was observed using a transmission electron microscope, and high-performance liquid and gas chromatography were used to analyze the dynamic changes of phytohormones in the abscission zone during the calyx abscission process of Korla fragrant pears, and mass spectrometry imaging was applied to ascertain the spatial distribution of phytohormones. The results revealed that the mitochondria in the abscission zone of the decalyx fruits were regularly distributed around the cell wall, and the chloroplasts were moderately present. In contrast, in the persistent calyx fruit, the corresponding parts of the abscission zone showed a scattered distribution of mitochondria within the cells, and there was a higher number of chloroplasts, which also contained starch granules inside. Mass spectrometry imaging revealed that ABA was enriched in the abscission zone of the decalyx fruit, and their ionic signal intensities were significantly stronger than those of the persistent calyx fruit. However, the ionic signal intensities of Indole-3-acetic acid (IAA) and Gibberellin A3 (GA3) of the persistent calyx fruit were significantly stronger than those in the abscission zone of the decalyx fruit and were concentrated in the persistent calyx fruit. 1-Aminocyclopropanecarboxylic Acid (ACC) did not show distinct regional distribution in both the decalyx and persistent calyx fruits. Furthermore, before the formation of the abscission zone, the levels of IAA, GA3, and zeatin (ZT) in the abscission zone of the decalyx fruits were significantly lower than those in the persistent calyx fruits by 37.9%, 57.7%, and 33.0%, respectively, while the levels of abscisic acid (ABA) and ethylene (ETH) were significantly higher by 21.9% and 25.0%, respectively. During the formation of the abscission zone, the levels of IAA, GA3, and ZT in the abscission zone of the decalyx fruits were significantly lower than those in the persistent calyx fruits by 41.7%, 71.7%, and 24.6%, respectively, while the levels of ABA and ETH were significantly higher by 15.2% and 80.0%, respectively. After the formation of the abscission zone, the levels of IAA and GA3 in the abscission zone of the decalyx fruits were lower than those in the persistent calyx fruits by 20.8% and 47.8%, respectively, while the levels of ABA and ETH were higher by 271.8% and 26.9%, respectively. In summary, during the calyx abscission process of Korla fragrant pears, IAA and GA3 in the abscission zone inhibited abscission, while ABA and ETH promoted calyx abscission. These research findings enrich the understanding of the regulatory mechanism of plant hormones on calyx abscission and provide a theoretical basis for the study of exogenous plant growth regulators for regulating calyx abscission in Korla fragrant pear.

Method Development and Validation of Stability-Indicating HPLC-UV Method for Determination of 5 -Fluorouracil

Introduction: In the realm of pharmaceutical analysis, the development and validation of a High-Performance Liquid Chromatography with Ultraviolet Detection (HPLC-UV) method for the precise determination of 5-FU stand as a crucial endeavor. Methods: This study outlines the systematic process of method development, optimization, and subsequent validation to ensure the reliability and applicability of the method in pharmaceutical quality control. Method optimization included the selection of an appropriate stationary phase, mobile phase composition, and chromatographic conditions to achieve optimum resolution, sensi-tivity, and run time. Results: A speedy, simple, and dependable HPLC technique for quantifying 5-FU on a C18 (250 4.6 mm, 5m particle size) column with solvent A included 10 mM phosphate buffer with pH 3.0 and solvent B with acetonitrile as the mobile phase. At 250 nm, the effluent was measured. Fur-ther, 5-FU had a retention time of 1.698 minutes. Conclusion: According to ICH criteria, the devised technique was validated for precision, accu-racy, linearity range, robustness, and ruggedness.

RP-HPLC Study of the Complexation of Acetamiprid, Imidacloprid and Carboxin Guest Molecules With Thiophosphorylated Calix [6] Arene in Dimethylformamide-Acetonitrile-Water Mobile Phase.

Reversed-phase high-performance liquid chromatography was used to study the host-guest complexation of thiophosphacalixarenes (TPC 1-3) with acetamiprid, imidacloprid and carboxin as guests. The Onyx Monolithic C 18 column (150 × 0.1mm) and Phenomenex® were used with UV detection at 254nm. The mobile phase consisted of dimethylformamide-acetonitrile-water. The association constant of the 1:1 guest-host complexes was determined from the relationship between the retention factor of the guest and concentration of the thiophosphacalix [6] arene host in the mobile phase. The stability constants are influenced by size, nature, position and quantity of substituents in the benzene ring of the calixarene skeleton. The detection limits for TPC 1, TPC 2 and TPC 3 are 0.95, 1.20 and 1.40μg/mL, while the quantification limits are 2.85, 3.60 and 4.20μg/mL for TPC 1, TPC 2 and TPC 3, respectively.

Analyzing Paxlovid: Examining Its Properties, Characteristics, and Analytical and Bio‐Analytical Methods–A Comprehensive Review

ABSTRACTPaxlovid, a novel antiviral medication developed by Pfizer, has attracted considerable attention as a coronavirus disease 2019 therapeutic since it may be effective in treating the severe acute respiratory syndrome coronavirus type 2‐caused disease. Paxlovid is known as a combination therapy since it includes two agents, Nirmatrelvir and Ritonavir, which both are involved in the viral replication process inhibition. A further discussion of the molecular structure, pharmacokinetics, and pharmacodynamics of both components will help comprehend Paxlovid's mechanism of impact and effectiveness. High‐performance and spectroscopic methods, including high‐performance liquid chromatography (HPLC), infrared, and ultraviolet‐visible spectroscopy have been among the methods employed for compound identification, quantification, and structural elucidation. Bioanalytical methods have also made a significant contribution to the evaluation of Paxlovid's pharmacokinetic parameters, bioavailability, and metabolism in biological matrices. LC‐tandem mass spectrometry (LC‐MS/MS) is widely employed for the quantification of Paxlovid and its metabolites in plasma, serum, and other biological samples. This study brings forth an overview of the characteristics and properties of Paxlovid along with analytical and bioanalytical methods employed for its assessment and quantification.

Phytohormonal balance and differential gene expression in chronically irradiated Scots pine populations from the chernobyl affected zone.

The impact of chronic radiation exposure on phytohormone content and expression of phytohormone- and stress-related genes of Scots pine in the zone affected by the Chernobyl accident was studied. Needle samples were collected from three plots with contrasting levels of radioactive contamination in the Polesye State Radiation-Ecological Reserve, Republic of Belarus, and two reference plots in the Kozeluzhsky forest in June 2022. The experimental plots were located within the artificial plantations of Scots pine established in 1982, before the accident in 1986. The activity of radionuclides 137Cs, 90Sr, 241Am, 238Pu, and 239+240Pu in soil and needles ensured dose rates ranging from 3.3 to 87 mGy × year-1, while at the reference plots, the range was 0.7‒0.8 mGy × year-1. Concentrations of plant hormones, including indole-3-acetic acid (IAA), indole-3-butyric acid (IBA), zeatin, and abscisic acid (ABA) in needles were evaluated using high-performance liquid chromatography (HPLC). We demonstrate that chronic radiation exposure is a significant stress factor that affects both phytohormonal balance and the expression of some important phytohormone- and stress-related genes. We found a tendency toward decreased ABA and auxin concentrations in trees from plots contaminated with radionuclides. The ratio (IAA + IBA + zeatin)/ABA was drastically raised at the most contaminated plots Masany and Kulazhin, reflecting the functional rearrangements of cellular metabolism that ensure plant adaptation under chronic radiation exposure. Changes in gene expression indicated modulation of ABA and Ca2+ signalling pathways, decreased potential of zeatin biosynthesis, and activation of heat shock proteins biosynthesis.

Optimization, characterization and biosafety of carotenoids produced from whey using Micrococcus luteus

This study aimed to optimize the production of carotenoid pigments from Micrococcus luteus (ATCC 9341) through the statistical screening of media components and the characterization of antimicrobial, antioxidant, cytogenetic and cytotoxic activities. A BOX-Behnken design was used to assess the effects of whey concentration, inoculum size, pH, temperature, and agitation speed on carotenoid yield. The optimum combination increased production to 2.19 g/L, with a productivity of 0.045 g L-1 h−1 and a productivity yield of 0.644 g/g, as confirmed by an observed carotene production of 2.19 g/L. The final response surface model fitting the data had an R2 of 0.9461. High-performance liquid chromatography (HPLC) analysis identified 12 carotenoid pigment compounds produced by M. luteus. The extracts displayed moderate antimicrobial efficacy against Gram-positive bacteria such as Bacillus cereus (ATCC 11778), Staphylococcus aureus (ATCC 6538), and E. faecalis (ATCC 19433), with inhibition zone diameters (IZD) of 29.0, 14.0, and 37.0 mm, respectively, at 1000 μg/mL. However, its effectiveness against Gram-negative bacteria is limited. In comparison, tetracycline exhibited greater antimicrobial potency. The IC50 value of carotenoids was used to indicate the antioxidant activity. IC50 value from the DPPH assay was 152.80 mg/100mL. An IC50 cytotoxicity value greater than 300 μg/mL was found against normal mouse liver cells, with over 68% cell viability even at 300 μg/mL, indicating low toxicity. Histological structure studies revealed normal myocardial muscle tissue, lung tissue, and kidney tissue sections, whereas liver tissue sections revealed ballooning degeneration of hepatocytes and disorganization of hepatic cords. Cytogenetic parameters revealed that the carotene treatment group had a mitotic index (70%) lower than that of the control but higher than that of the positive control, mitomycin, and did not substantially increase numerical (1.2%) or structural aberrations compared with those of the control, suggesting a lack of genotoxic effects under the experimental conditions. In conclusion, optimized culture conditions enhanced carotenoid yields from M. luteus, and the extracts displayed promising bioactivity as moderate antibiotics against certain gram-positive bacteria and as antioxidants. The high IC50 values demonstrate biosafety. Overall, this bioprocess for enhanced carotenoid production coupled with bioactivity profiling and low cytotoxicity support the application of M. luteus carotenoids.

RECENT ADVANCES IN GAS, LIQUID AND SUPERCRITICAL FLUID CHROMATOGRAPHY IN THE CONTEXT OF SUSTAINABLE/ GREEN CHEMISTRY

Background: Chromatographic techniques such as gas chromatography (GC), liquid chromatography (LC) and supercritical fluid chromatography (SFC) have long been employed in analytical chemistry. However, using or producing certain organic solvents and non-renewable gases is hazardous to the environment. Green chemistry is essential for addressing the environmental hazards associated with traditional procedures. Objectives: This review focuses on recent updates and profound insights into new, greener techniques introduced in GC, LC and SFC. Methodology: To compile this review, several electronic databases were searched, preferably from January 2019-December 2023. Results: This review highlights advancements in miniaturization, rapid methods, and eco-friendly solvents in chromatographic techniques. Integrating micro-electro-mechanical systems (MEMS) and nano-electro-mechanical systems (NEMS) in GC enhances sensitivity and resolution while reducing solvent consumption. Innovations like monolithic micro-GC chips and the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method further streamline analysis times. In LC, supercritical fluids are utilized as green mobile phases, optimizing techniques like electrochemical flow liquid chromatography (EFLC), high-performance liquid chromatography (HPLC), and ultra-high-performance liquid chromatography UHPLC. In contrast, SFC employs rapid methods, such as ultra-high-performance supercritical fluid chromatography-mass spectrometry (UHPSFC-MS). These developments collectively promote sustainability and efficiency in chromatographic practices. Conclusion: Green chromatography has become an essential tool in pharmaceutical analysis because it safeguards the operator’s health and the environment. It opens new horizons and generates new ideas for further experimentation while focusing on recent cutting-edge green technologies incorporated in GC, LC and SFC. These advancements significantly enhance safety and sustainability in analytical practices.

A Review on Advancement in Analytical Quality by Design (AQbD)

Analytical Quality by Design (AQbD) represents a transformative methodology in pharmaceutical development, anchored in a systematic, risk-based, and data-driven framework. This approach optimizes analytical methods, fostering heightened product quality, efficient regulatory compliance, and informed decision-making. The industry's increasing acceptance of AQbD principles signifies a paradigm shift towards enhanced efficiency, sustainability, and global harmonization. This review comprehensively explores AQbD principles, regulatory perspectives, and its applications, particularly in analytical method development, including high-performance liquid chromatography (HPLC) and high-performance thin-layer chromatography (HPTLC). Emphasis is placed on the symbiotic relationship between AQbD and analytical method validation (AMV), elucidating their collective role in ensuring reliable and accurate analytical results. Integrating AQbD in method transfer, automation, and control strategies underscores its pivotal role in achieving robust, efficient, and compliant analytical processes. The review delves into lifecycle management and continuous improvement, coupled with AQbD principles, ensuring sustained method reliability throughout the pharmaceutical product lifecycle. AQbD's significant contribution to pharmaceutical lifecycle management, optimization, and change control is explored, emphasizing its systematic, data-driven, and risk-based approach to method development, validation, and ongoing enhancement. This review illuminates AQbD's transformative impact on pharmaceutical analysis, aligning with industry trends toward quality, efficiency, and regulatory compliance.

Tilianin obtained from Agastache mexicana inhibits monoamine oxidase and modifies depressive behavior in rats.

Agastache mexicana is used in traditional medicine to treat anxiety, insomnia, pain, among others. In a previous study, the methanolic extract exerted anxiolytic and sedative effects, as observed behaviorally, associated with one of its major components, tilianin. To assess the effect produced by the extracts and tilianin obtained from Agastache mexicana on depressive-induced behavior model and on the activity of monoamine oxidases (MAOs). The depression experimental model consisted of the forced swimming test in rats. MAOs activity was evaluated in cortex and hippocampus from the tilianin and Agastache extracts treated rats using specific inhibitors for each isoform. The quantification of monoamines was carried out using an High Performance Liquid Chromatography method. An increase in the swimming time was observed in rodents treated with doses of 16 (226.6±5.5 seconds) and 50mg/kg (237.8±5.7 seconds) of tilianin, methanolic (260.4±3 seconds), and hydroalcoholic extracts (249.6±2.6 seconds) at 100mg/kg. MAOs activity was significantly decreased in brain tissue from animals treated with 16 and 50mg/kg of tilianin, methanolic, and hydroalcoholic extracts at 100mg/kg. The tilianin effect on monoamine oxidases inhibition is confirmed, suggesting its potential use in the treatment of certain neurological disorders.

Comparative Bioequivalence Studies of doxysam and doxycycline (Pfizer) by reversed phase HPLC.

Isocratic high performance liquid chromatography on reversed phase a (150x 4.6 mm I.D), 5 ?m ?-Bondapak RP-8 column (with acidic mobile phase allow the separation of doxcycycline hydrochloride with low detection limit of 0.2 µg/ml detected by UV set at 226 nm. The method was validated for Doxycycline between 0.156- to 5 µg/ml. The concentration of doxycycline was assessed in two single dose randomized crossover studies with intervals of one week between two period. In sera of 20 adults healthy male volunteers with average age of (42 + 10) year, body weight 48-85 kg, body height of (160-185cm) after a single dose of doxycycline hydrochoride 100 mg in form of capsules were orally administrated for both formulations. The blood samples (2ml) were drawn concomitantly from 0.5 – 24 hours. µg The pharmacokinetics parameter were obtained from the mean serum concentration measured at various sampling times for both formulations. The maximum peak concentration (Cmax) of doxycycline reference drug from Pfizer In serum was (3.1 +0.094 µg /ml) attained in 2 hrs. While the maximum concentration (Cmax) of test drug doxysam (2.8 +0.098 µg /ml) attained in about 2 hrs, both drug have long elimination time with half time of approximately (13 hrs.) Both test and reference drug were show no significant difference in pharmacokinetics parameters, so they were considered to be bioequivalent.

Determination of an Anti-Parasitic Active Pharmaceutical Ingredient in Wastewater Effluents Using Capillary Zone Electrophoresis.

Ireland has a successful pharmaceutical industry with over 100 pharmaceutical manufacturing sites across the island. Although this success has many benefits, the irreversible effects emissions from pharmaceutical manufacturing can have on the environment are a major drawback. Although known pollutants are regularly monitored with limits set out by the Environmental Protection Agency, one significant pollutant has been overlooked: pharmaceutical pollution. Detecting these pollutants and ensuring they are at a safe concentration for the environment is of utmost importance. In recent years, capillary electrophoresis is being recognised as a suitable alternative to high-performance liquid chromatography due to its many benefits such as faster analysis, water-based buffers and smaller sample volumes. In this paper, a capillary zone electrophoresis (CZE) method with a preconcentration step of solid-phase extraction was developed for an anti-parasitic active pharmaceutical ingredient (API) called ZB23. The API was successfully detected in a wastewater sample in less than 10min using the CZE parameters of 25mM borate buffer with a pH of 10.5, 15% MeOH, 10kV voltage, 25mbar for 5s injection size, an Lt of 40cm, an Ld of 31.5cm and a detection wavelength of 214nm.

Chemistry of scented nectar in the black lily Fritillaria camtschatcensis (Liliaceae)

AbstractVolatile compounds in floral nectar may affect plant–pollinator relationships; however, the understanding of the distribution and functions of scented floral nectar is still relatively limited. In this study, we examined the volatile constituents of the scented floral nectar of the black lily Fritillaria camtschatcensis and their potential to attract flower‐visiting flies. In Japan, F. camtschatcensis comprises two varieties, var. camtschatcensis (lowland) and var. keisukei (alpine). The flowers of both varieties secrete large amounts of nectar that is fed on by visiting flies. We investigated the sugar concentration of the nectar using high‐performance liquid chromatography (HPLC) and studied its volatile chemical composition using gas chromatography–mass spectrometry. We conducted a bioassay using a synthetic mixture of nectar volatiles of the lowland variety to test whether flies are attracted to volatile compounds in the nectar scent. HPLC analysis showed that glucose and fructose occur in the nectar of the alpine variety, whereas the lowland variety nectar contained glucose but lacked fructose. Nectar volatile compounds differed substantially between the two varieties; the volatiles of the lowland variety consisted primarily of four aliphatic acids, whereas acetophenone was the main volatile compound in the alpine variety. The bioassay showed that a mixture of three aliphatic acids detected as volatiles of the lowland variety nectar attracts flies, including those that visit the alpine variety flowers such as Calliphoridae. These results suggest that the volatiles of the scented nectar serve as attractants for flower visitors and may have an important role in the pollination of F. camtschatcensis.

In vial thin-film solid-phase microextraction using silver nanoparticles as coating for the determination of phenols in waters

A novel thin-film solid-phase microextraction (TF-SPME) device based on glass vials internally coated with silver nanoparticles (AgNPs) was developed for the first time, and used for determining five phenols in wastewater, bottled water, and irrigation water samples by high-performance liquid chromatography coupled to a photodiode array detector (HPLC-PDA). Different AgNPs were synthesized varying the ratio of metallic salt versus the reduction agent, and the pH of the synthesis. The preparation of the TF-SPME glass vial device was optimized in terms of the type of AgNPs used and the number of layers of AgNPs. Besides, the TF-SPME procedure was also optimized. The TF-SPME method was very simple, only requiring the addition of 18 mL of water and 5 min of agitation, followed by the disposal of the water and addition of the 750 µL as desorption solvent, and direct HPLC-PDA injection. The entire method showed adequate analytical performance, with limits of detection ranging from 3 to 8 μg·L-1, and intra-day and inter-day precision (as RSD), both evaluated with different vials and therefore showing inter-batch precision, with values between 8.70 and 16.4 %, and 6.0 and 19.7 %, respectively. The TF-SPME-HPLC-PDA procedure was compared with previous methods for the determination of phenols, both in terms of analytical performance and greenness assessments applying different metrics, showing clear advantages.

A strategy of Q-markers identification based on effect, property flavour material basis and rapid quantitative evaluation via near-infrared spectroscopy and chemometric methods for the quality control of Flos Trollii (FT)

Ethnopharmacological relevanceFlos Trollii (FT) is the dried flower of Trollius Chinensis Bunge of Ranunculaceae with the pharmacological properties of anti-inflammatory, antibacterial, antiviral, anti-oxidative. The herb FT is not only a traditional Chinese medicine (TCM) but also an extensively utilized ethnic medicine, employed by diverse ethnic groups including Mongolian, Tibetan, and Kazakh. Aim of studyFT was taken as an example to construct a strategy of quality markers (Q-markers) identification based on effect, property flavor material basis, and rapid quantitative evaluation using near-infrared (NIR) spectroscopy and chemometric methods of TCM. Materials and methodsInitially, the anti-inflammatory efficacy of FT from three places of origin was evaluated using the RAW264.7-cell inflammatory model, and the bitter property flavor was characterized using an electronic tongue. The high-performance liquid chromatography(HPLC) fingerprint of FT was generated, and the quality of FT from different origins was evaluated employing chemometrics. Next, potential anti-inflammatory and bitter property flavor compounds were screened utilizing a fingerprinting-effect relationship and fingerprinting-property flavor relationship model using partial least squares regression (PLSR). The Q-markers of the FT were confirmed based on the testability principle. Then, a swift, uncomplicated, and precise Q-marker content of the FT prediction model was developed by adopting NIR. ResultsThe main common fingerprinting peaks affecting FT's efficacy and property flavor were screened. Five of these compounds, 2″-O-beta-L-galactopyranosylorientin, orientin, vitexin, veratric acid, and isoquercitrin, characterized using HPLC and ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS), could be regarded as Q-markers of FT. Q-marker content of the FT prediction model developed adopting NIR spectroscopy was rapid and effective. ConclusionAccording to the strategy proposed in this study, a quantitative NIR spectroscopic method to identify Q-markers could be a tool to improve the QC efficiency of TCM.

The molecular mechanisms of Caulophyllum robustum Maxim extract inhibition by regulating FAK/PI3K signaling pathway in gastric cancer HGC-27 cells

Ethnopharmacological relevanceCaulophyllumrobustum Maxim extract (CRME), as recorded in traditional Chinese medicine, has the function of dispelling Feng, regulating Qi and dredging collaterals, promoting blood circulation and regulating menstruation, gingering up and relieving pain, clearing heat simultaneously detoxifying, lowering blood pressure and hemostasis. CRME is often used as Chinese materia medica preparation for rheumatoid arthritis, traumatic injury, irregular menstruation, abdominal pain, and hypertension treatment. Since gastric cancer (GC) existed as a health problem of human over the years, we are committed to the development of potential components of Chinese herbal medicine curing cancer, and we found CRME is expected to be one of the effective anti-tumor traditional Chinese medicine preparations. Aims of the studyTo investigate the molecular mechanisms of CRME anticancer effects and the potential links between CRME and FAK. Materials and methodsCaulophyllumrobustum Maxim was extracted to obtain CRME, high-performance liquid chromatography (HPLC) was used for qualitative analysis. Information about CRME was collected from traditional Chinese medicine records and local surveys unpublished internationally. Series of cellular function experiments were applied to detect cell proliferation, migration, apoptosis, autophagy, cell cycle, angiogenesis. The xenograft model is employed in vivo. ResultsCRME can significantly inhibit HGC-27 cells on proliferation, migration and angiogenic capacity. Xenograft model indicated CRME inhibited cell proliferation in vivo. Annexin V-FITC/PI double staining assay and PI single staining assay depicted that CRME induces cell apoptosis, and arrests cell cycle at G0/G1 phase. AO (acridine orange) staining assay showed that CRME promoted autophagosome formation and inhibited autophagic flow. HPLC indicated Cauloside A and Cauloside C are components of CRME. Western blot indicated that FAK/PI3K signaling pathway is critical in the inhibition of CRME on HGC-27 cells. ConclusionsThe anti-tumor components of CRME, Cauloside A and Cauloside C, inhibited tumor progression in HGC-27 cells. This inhibition is achieved by decreasing the phosphorylation levels of FAK, thereby modulating PI3K/AKT signaling pathway.

Contents of sensitising rubber accelerators in disposable rubber gloves: A Copenhagen market survey.

Rubber gloves contain rubber accelerators that may cause contact allergy. The content of sensitising rubber accelerators in contemporary rubber gloves is not well known. Identify and quantify the content of rubber accelerators in disposable rubber gloves. Fifty-one gloves of 49 different brands were collected. Forty-eight of the gloves were disposable and three re-usable. The gloves were analysed for their content of sensitising rubber accelerators, that is, zinc dithiocarbamates, thiurams, thiazoles/benzothiazoles, diphenylguanidine, and thioureas by high-performance liquid chromatography. Rubber accelerators were identified in 43/48 (90%) of the disposable gloves. In total, 39 gloves contained zinc dibutyldithiocarbamate (ZDBC) (0.18-1.96 mg/g), 34 zinc diethyldithiocarbamate (ZDEC) (0.032-2.78 mg/g), three zinc dibenzyldithiocarbamate (0.65-1.4 mg/g), one zinc dimethyldithiocarbamate (0.23 mg/g), and one 1,3-diphenylguanidine (0.21 mg/g). 2-cyanoethyl dimethyldithiocarbamate (CEDMC) was identified in three gloves (<0.052 mg/g). The one glove labelled as accelerator free contained ZDBC (1.07 mg/g). Only few glove packages had the specific content of rubber accelerators labelled. The most frequent rubber accelerators in rubber gloves are ZDEC and ZDBC. Accelerator-free gloves may contain rubber accelerators. Full labelling of rubber gloves is needed and producers should be sure not to falsely claim that the rubber gloves are free of rubber accelerators.