High-performance Liquid Chromatography Research Articles

Improvement and Application HPLC-UV Method for detecting of N-drugs in Pharmaceutical Formulations

The ultraviolet-visible high-performance liquid chromatography (HPLC–UV) coupled method was developed to detect five pharmaceutical compounds: indapamide (INDP), clomipramine (CMI), promethazine HCl (PMH), lisinopril (LSP) and trifluoperazine HCl (TFPH). The mobile phase consisted of 70% acetonitrile and 30% water, ensuring specific retention times (tR) for each compound. Analytical validation parameters were calculated from a calibration curve, including sensitivity, limit of detection (LOD) and linearity of the method. The LOD values of N-drugs were calculated as 6.24 μM for INDP, 2.19 for CMI, 10.57 for PMH, 6.68 for LSP and 1.25 for TFPH. Peak deconvolution or spectral deconvolution of standard solutions of drug mixtures was used to separate overlapping peaks in a dataset and extract information about individuals. Chromatographic separation of the standard mixture of pure compounds achieved a good resolution (R_s), ensuring the effective separation of the mixture components. However, other mixtures did not achieve satisfactory resolution due to retention time interference. Overall, the HPLC–UV method demonstrated good sensitivity and selectivity for the detection of the chosen pharmaceutical compounds. KEYWORDS Chromatogram, deconvolution, limit of detection, pharmaceutical analysis, retention time, sensitivity

Unraveling relationship between the genetic polymorphism CYP2A13 and nicotine metabolism of male smokers in Medan, Indonesia

BackgroundNicotine metabolism significantly influences the levels of harmful nicotine metabolites in smokers. CYP2A13, a key enzyme in nicotine and xenobiotic metabolism, is implicated in tobacco smoke-related lung cancer.AimThis study investigated the association between CYP2A13 genetic polymorphism and nicotine metabolism in male smokers in Medan, Indonesia.Materials and methodsThis cross-sectional study included 66 male smokers (aged 20–65 years) who met pre-defined inclusion and exclusion criteria. Nicotine metabolite levels were quantified in urine samples using high-performance liquid chromatography (HPLC). CYP2A13 polymorphism was determined using polymerase chain reaction-restriction fragment length polymorphism (PCR–RFLP) analysis of venous blood samples. Logistic regression analysis (Epi Info-7) assessed the association between CYP2A13 genotype and nicotine metabolism.ResultsNo significant association (p > 0.05) was found between CYP2A13 genotype and nicotine metabolism. The CC genotype was most prevalent. The majority of participants exhibited rapid nicotine metabolism.ConclusionFurther research with larger sample sizes and diverse populations is needed to elucidate the relationship between CYP2A13 genetic polymorphism and nicotine metabolism.

Impaired cognitive function and decreased monoamine neurotransmitters in the DNAJC12 gene knockout mouse model

BackgroundHyperphenylalaninemia, a prevalent amino acid metabolism disorder, often results in cognitive impairment. Recent studies have identified a rare variant of this disorder caused by mutations in the DNAJC12 gene. The specific mechanisms by which DNAJC12 mutations lead to hyperphenylalaninemia and the lack of an animal model for study remain significant gaps in understanding.PurposeThis study aims to elucidate the role of DNAJC12 in intellectual disability and explore the mechanisms by which DNAJC12 deficiency leads to hyperphenylalaninemia through developing a DNAJC12 gene knockout mouse model.MethodsWe thoroughly examined the clinical features and genetic mutations evident in two patients with biallelic mutations in the DNAJC12 gene. Based on the patient’s mutation locations, we determined the target site for the knockout utilizing CRISPR/Cas9 technology. To assess the impact of these mutations on DNAJC12 expression, we used quantitative real-time PCR and Western blotting techniques to measure mRNA and protein levels, respectively. The Morris water maze test was administered to evaluate the cognitive functions of the mice. Additionally, we utilized High-Performance Liquid Chromatography (HPLC) to measure serum aromatic amino acids and brain monoamines, facilitating an investigation into the metabolism of phenylalanine and tyrosine.ResultsWe reported two patients with mutations in the DNAJC12 gene. Case 1 carried the mutations c.158-1G > A and c.262 C > T in the DNAJC12 gene. He presented with nocturnal eye closure, crying, and arching back in reverse tension before treatment, suggesting a neurotransmitter metabolism disorder. Case 2 carried the mutations c.473 C > G, and c.102 deletion in the DNAJC12 gene. He showed elevated blood phenylalanine levels, although further clinical details were not available. Based on the patients’ mutation locations, exons 2–4 of the DNAJC12 gene were targeted and eliminated. In our animal model experiments, DNAJC12 gene knockout mice exhibited a complete absence of DNAJC12 expression at both mRNA and protein levels. These knockout mice showed significant deficits in learning and memory performance as assessed by the Morris water maze test. Quantitative real-time PCR analysis indicated no significant differences in the levels of aromatic amino hydroxylases between knockout and wild-type mice. However, Western blot analysis revealed a substantial reduction in phenylalanine hydroxylase (PAH) protein levels in the liver of knockout mice, while tyrosine hydroxylase (TH) and tryptophan hydroxylase 2 (TPH2) expression remained unchanged. HPLC analysis demonstrated increased serum Phe concentrations and decreased levels of brain neurotransmitters in the knockout group.ConclusionsWe report two patients with four novel DNAJC12 mutations (c.158-1G > A, c.262 C > T, c.473 C > G, c.102delT), expanding the mutation spectrum. Based on the patients’ mutation location, we established the first DNAJC12 gene knockout mouse model. The knockout mice exhibit hyperphenylalaninemia, impaired cognitive function, and decreased monoamine neurotransmitters. DNAJC12 deficiency may contribute to the clinical phenotype via the PAH pathway, potentially at the post-transcriptional level.

Protection of stainless steel surfaces in desalination units against corrosion during acid cleaning under dynamic conditions by using lavender angustifolia extract as a green inhibitor

This study investigates the thermodynamics, kinetics, and adsorption mechanisms of Lavender angustifolia extract (LAE) as a corrosion inhibitor for stainless steel (316SS) in desalination units. The primary aim is to evaluate the efficacy of LAE in mitigating corrosion in a 5.0 M HCl solution under dynamic conditions. High-Performance Liquid Chromatography (HPLC) analysis identified key components of the LAE extract that contribute to corrosion inhibition, including linalyl acetate (41.7%), linalool (13.6%), 1,8-cineole (8.3%), β-ocimene (6.2%), terpinen-4-ol (5.7%), lavandulyl acetate (7.5%), and camphor (4.7%). Results indicate that the inhibitory efficiency of LAE increases with concentration, peaking at 94.3% at 300 mg L⁻¹. The Freundlich adsorption isotherm model best describes the experimental adsorption data. Notably, the activation energy for corrosion increases from 7.17 kJ mol⁻¹ in the 5.0 M HCl solution to 21.65 kJ mol⁻¹ with the addition of LAE, reflecting enhanced protection. The enthalpy change (∆H*) in the presence of LAE (19.04 kJ mol⁻¹) is significantly greater than that of the extract-free solution (4.55 kJ mol⁻¹), indicating improved corrosion resistance of 316SS. Electrochemical techniques confirmed the mixed-type inhibition behavior of LAE, while UV and SEM-EDAX analyses demonstrated effective adsorption of the extract on the stainless steel surface.

Gut Microbiota-Mediated Degradation of Food-Grade Lambda-Carrageenan by Bacteroides xylanisolvens and Its Role in Inflammation.

Concerns about the safety of food additives have intensified among consumers, scientists, and policymakers. Ensuring the safety of these additives is crucial to public health. Carrageenan (CGN), a common additive in the food industry, has become the subject of controversy, particularly regarding whether it can be degraded in the gastrointestinal tract, forming degraded carrageenans (dCGNs) that may pose health risks. This study is among the first to identify Bacteroides xylanisolvens C3 as a key gut bacterium involved in the degradation of food-grade lambda-CGN (L-CGN). Using high-performance liquid chromatography (HPLC), thin-layer chromatography (TLC), and metabolic analysis, we confirmed the ability of this bacterium to degrade L-CGN. Importantly, we found that the microbiota-generated dCGNs significantly increased nitric oxide (NO) and COX-2 production and upregulated pro-inflammatory genes, including IL-1β, TNF-α, and IL-6, in macrophages. This study also highlights how microbial degradation of L-CGN can drive inflammation, particularly through the activation of the Nrf2 and NLRP3 pathways. These results suggest that microbial degradation of L-CGN in the gut may contribute to inflammation, underscoring the need to better understand microbial interactions with food-grade L-CGN, particularly in the context of colon health and inflammation-related diseases such as inflammatory bowel disease.

Phytochemical Profile and Anticancer Activity of Achillea conferta Leaf Extracts: Insights into Antioxidant Properties.

This study explores the phytochemical composition and biological potential of extracts from Achillea conferta leaves, specifically Hydroethanolic Extract (HE), Total Flavonoid Extract (TFE), and Glycoside Flavonoid Extract (GFE). Phytochemical screening of HE revealed significant concentrations of phenolic compounds, flavonoids, and tannins, quantified as 48.36 µg GAE/mL extract, 32.40 µg QE/mL extract, and 4.85 µg TAE/mL extract, respectively. High-Performance Liquid Chromatography (HPLC) identified key flavonoids in TFE and GFE, including catechin, epigallocatechin, hesperidin, myricetin, rutin, isorhamnetin, and luteolin. Antioxidant activities were assessed using assays for reactive oxygen species (ROS), total peroxides, and free radical scavenging (DPPH). GFE demonstrated the highest ROS concentration at 269 µM/g extract. The antiproliferative effects on breast, esophageal, and large intestine cancer cell lines were evaluated, with GFE showing greater efficacy than TFE in all tested cell lines, highlighting the therapeutic potential of A. conferta extracts. These findings highlight the medicinal potential of A. conferta as a natural source of antioxidants and anticancer agents. However, further research is necessary to explore detailed mechanistic pathways and the in vivo efficacy of these extracts.

Emergence of MDR Enterobacter hormaechei RSM5 in Pharma Effluent and its Implications in β-lactam Antibiotic Removal from Effluent.

Antibiotic resistance poses the biggest threats to global health and development and also to food security. β-lactam antibiotics (BLAs) responsible for the transpeptidation/cross-linking process during cell wall biosynthesis contribute to the maximum resistance. The production of β-lactamase enzyme is a significant contributing factor to the development of antibiotic resistance to β-lactam antibiotics. Unintentional disposal of antibiotics from the manufacturing units of pharma industries to the water bodies enhances the exposure of antibiotics, contributing to resistance. This study describes the presence of > 50 antibiotic-resistant bacterial strains in pharma effluent of Himachal Pradesh, India. Among 54 isolates, 40% showed ampicillin resistance above 100µg/mL, 13% showed resistance above 5000µg/mL, and 3 strains showed resistance at 15,000µg/mL of ampicillin. Enterobacter hormaechei RSM5 showed the highest minimum inhibitory concentration (MIC) and cell viability and was selected for further studies. It produces lactamase (0.24 U/mL) to resist the higher concentration of antibiotics present in the media/effluent and demonstrated resistance against 3 different classes of antibiotics, confirming its status as a multidrug resistance (MDR) strain. The high-performance liquid chromatography (HPLC) analysis of the isolate demonstrated that Enterobacter hormaechei RSM5 can degrade ampicillin within 24h of incubation in medium/effluent. The emergence of Enterobacter as a pathogen with antibiotic resistance poses a significant health concern that could also be explored for the removal of antibiotics from the effluent at the source. The future of research in this area needs to be open and mindful of new approaches.

Refining the adriamycin-induced focal segmental glomerulosclerosis mouse model to improve reproducibility and animal welfare.

Reliable animal models are crucial to drug development for focal segmental glomerulosclerosis (FSGS), a rare kidney disease. Variability in success rates in literature and significant ethical concerns with animal welfare necessitate further optimization of adriamycin (ADR)-induced FSGS model developed on BALB/c mice. High-performance liquid chromatography (HPLC) was used to assess ADR stability in water and upon light exposure. To identify the optimal ADR level, single intravenous ADR injections with dosing levels from 10 to 17 mg/kg body weight were administered to BALB/c mice to induce FSGS-like pathology. Body weight and proteinuria of FSGS mice were monitored and analyzed for FSGS model-associated morbidity. Animals were euthanized for hematological and kidney histological assessments 8 weeks post induction. To identify the suitable experiment time frame of the ADR-induced FSGS mouse model, a longitudinal study was performed, with an 11-week continuous monitoring of the symptoms. ADR was found to be unstable in aqueous media and light sensitive. A dosing level of 10.5 mg/kg of ADR was optimal for consistent FSGS mouse model induction on BALB/c strain, characterized by minimal mortality and sustained FSGS-like symptoms. Findings from the longitudinal study suggest that 6 weeks post ADR induction may represent the peak of FSGS pathology severity in this mouse model. This time frame may be used for FSGS drug development projects. Based on the outcome from this study, we identified the optimal ADR dosing level and model testing duration. A standard operating procedure (SOP) for the ADR-induced FSGS mouse model was established to facilitate FSGS basic research and drug development.

Collagen Hybridizing Peptide-Based Radiotracers for Molecular Imaging of Collagen Turnover in Pulmonary Fibrosis.

Pulmonary fibrosis is a characteristic feature of interstitial lung disease. Current clinical diagnostic methods provide a snapshot of the lung structure without information on disease activity. Collagen hybridizing peptides offer the opportunity to detect collagen remodeling through their hybridization with denatured collagen. Here, we sought to develop a 99mTc-labeled collagen hybridizing tracer to track denatured collagen invivo and validate it in a murine model of pulmonary fibrosis. Methods: Imaging agents consisting of a polyhistidine or a poly-histidine-glutamic acid [(HE)3] peptide connected to an N-terminal targeting moiety with 9 glycine-proline-hydroxyproline repeats [(GPO)9] through a 3-glycine linker were synthesized. After radiolabeling with 99mTc-tricarbonyl, the labeled products' purity and stability were evaluated by high-performance liquid chromatography and γ-well counting, and their biodistributions were compared in mice. To induce pulmonary fibrosis, the lungs of 8- to 10-wk-old mice were exposed to bleomycin (or saline as control). At 3 wk after induction, SPECT/CT imaging with 99mTc-(HE)3-(GPO)9 was performed 1 h after injection and was followed by tissue collection to assess 99mTc-(HE)3-(GPO)9 biodistribution by γ-well counting and to evaluate lung histology. The specificity of the tracer uptake was assessed using a scrambled homolog. A group of animals underwent serial imaging 3 and 8-10 wk after induction. Results: The specific activity of the final radiolabeled product was 70.3 ± 14.8 GBq/µmol. Radiolabeled tracers were stable in blood for at least 2 h and showed rapid blood clearance. 99mTc-(HE)3-(GPO)9 showed lower liver uptake in biodistribution studies and was selected for invivo imaging studies. SPECT/CT imaging of bleomycin-treated mice 3 wk after induction showed higher specific 99mTc-(HE)3-(GPO)9 lung uptake than that of control mice (P < 0.01) and that of bleomycin-treated mice 8-10 wk after induction, when fibrosis was resolved (P < 0.05). There was a significant correlation between lung uptake quantified by SPECT/CT and γ-well counting (Pearson R = 0.83, P < 0.001) and significant correlations between tracer uptake and indices of tissue fibrosis. Conclusion: 99mTc-(HE)3-(GPO)9 enables SPECT imaging of collagen turnover in pulmonary fibrosis. This approach expands the scope of existing diagnostic tools in fibrosis and can lead to better patient management by monitoring the effect of antifibrotic therapies.

Detection of Ochratoxin A in Tissues of Wild Boars (Sus scrofa) from Southern Italy

Ochratoxin A (OTA) is a secondary metabolite produced by fungi of the genera Aspergillus and Penicillium, known to contaminate various food substrates. Its toxic effects include direct nephrotoxicity, as well as observed teratogenic, immunogenic, and carcinogenic effects. Climate change may contribute to increased humidity and temperature, favouring fungal growth and, consequently, OTA spreading. Recent increases in wild boar populations, along with their omnivorous nature and their varied diet, define them as environmental bioindicators for contaminants like mycotoxins. This study aimed to assess the concentrations of OTA in kidney, liver, and muscle tissue samples from 74 wild boars that were hunted in different areas of Avellino, Campania region, between 2021 and 2022. Tissue samples underwent extraction, purification, and analysis using high-performance liquid chromatography (HPLC) coupled with a fluorescence detector. Results revealed OTA presence in 35.1% of tested wild boars. The highest OTA concentration was observed in the kidney and liver, with less in the muscle, indicating the presence of this mycotoxin in the wild boars and their surrounding environment. Consequently, there is a need to formulate rules for edible wildlife products. These findings emphasize the significant risk of OTA contamination in wild boar tissues, suggesting their potential as reliable environmental markers for mycotoxin prevalence and as a toxicological concern for human health.

The Effect of Environmental Factors on the Nitrate and Nitrite Metabolism of Oral Actinomyces and Schaalia Species.

Actinomyces naeslundii and Schaalia odontolytica belong to the most predominant nitrite-producing bacteria in the oral microbiome. Nitrite has antibacterial and vasodilatory effects that may contribute to maintaining oral and systemic health. We have previously elucidated the metabolic characteristics of the nitrite-producing activity of oral Veillonella species and the effects of oral environmental factors. However, this is still unknown for Actinomyces and Schaalia species. Furthermore, these bacteria are thought to degrade nitrite. Therefore, this study aimed to comprehensively elucidate the effects of environmental factors (pH, oxygen concentration, glucose, lactate, and the presence of nitrate/nitrite during growth) on nitrate and nitrite metabolism of these bacterial species using the type strains. Nitrite was quantified by Griess reagent, and final metabolites were analyzed by high-performance liquid chromatography (HPLC). The nitrite-producing activity of A. naeslundii and S. odontolytica was affected variously by environmental factors. Especially in A. naeslundii, under anaerobic conditions, the activity increased in a concentration-dependent manner with the addition of glucose or lactate and was higher at lower pH when lactate was added. The nitrite-degrading activity of both bacteria was lower than the nitrite-producing activity and was less affected by environmental factors. Metabolites from glucose by A. naeslundii were different with and without nitrate, suggesting that nitrate altered metabolic pathways. The growth was inhibited under anaerobic conditions but promoted under aerobic conditions. These results indicate that the nitrite-producing capacity of the oral microflora must take into account not only the composition and abundance of bacteria but also the variation in metabolic activity due to various environmental factors.

ИЗМЕНЕНИЕ СКОРОСТИ РАЗЛОЖЕНИЯ ПЕСТИЦИДОВ ПРИ ИХ СОВМЕСТНОМ ПРИМЕНЕНИИ В ПРОЦЕССЕ ПРОИЗВОДСТВА СЕЛЬСКОХОЗЯЙСТВЕННОЙ ПРОДУКЦИИ

The purpose of research is to study the dynamics of the decomposition of individual active ingredients of pesticides in plant tissues when used in tank mixtures. The field part of the study was carried out on the territory of the Educational, Scientific and Production Center for Horticulture and Vegetable Growing named after V.I. Edelshtein FSBEI HE Russian State Agrarian University – Moscow Timiryazev Agricultural Academy, the laboratory part was carried out at the Educational and Scientific Consulting Center “Agroecology of Pesticides and Agrochemicals” in Moscow during 2020–2021. Research was carried out on crops of spring wheat, oats, spring barley, peas, spring rape, potato plantings, as well as apple tree plantings. Chemical treatments were carried out with insecticides and fungicides approved for use on these crops – Skor, KE; Borey Neo, SK; Tilt, KE; Imidor, VRK; Kumir, SK; Sirocco, KE. The experiment included options with the use of drugs in tank mixtures and options with their separate use. Samples of plant products were taken for further analysis for pesticide content. In laboratory conditions, the level of residual amounts of active drugs in plant samples was analyzed using gas-liquid chromatography and high-performance liquid chromatography methods. The change in the level of pesticide residues in different experimental variants was assessed. The acceleration of the decomposition of the active substance, imidacloprid, on crops of peas, spring wheat, oats, spring barley and spring rape when used together with the drug Tilt, KE was established. Also, the use of the fungicide Skor, KE together with the insecticide Borey Neo, SK (150 g/l imidacloprid + 50 g/l lambda-cyhalothrin) on the apple tree caused a slowdown in the rate of decomposition of the active substances lambda-cyhalothrin and imidacloprid. The use of the copper-containing fungicide Kumir together with the insecticide Borey Neo, SK on the apple tree caused an acceleration of the disintegration of the active substance imidacloprid. The combined use of the fungicide Skor, KE with the insecticides Sirocco, KE and Borey Neo, SK accelerated the decomposition of the active substance difenoconazole.

Monoamine neurochemistry, behavior, and microhabitat contribute to male coquí frog modes: silent, territorial, and paternal.

Monoaminergic neurotransmitters are essential for a multitude of physiological and behavioral functions including territoriality and parental care. The Puerto Rican coquí frog, Eleutherodactylus coqui, possesses an intriguing multi-modal male behavioral organization whereby males can be territorial, paternal, and silent (non-calling). The objective of this study was to quantify central monoamines in the three male modes and integrate this neurochemistry with data from microhabitat shelter selection and male social structure. Males were assessed for monoamines and metabolites using high performance liquid chromatography with electrochemical detection. Results indicated that there are distinct and significant differences among the three male behavioral modes based on male social structure, microhabitat shelter selection, and neurochemistry. Silent males are non-combative, quiescent, occur nocturnally in relatively open locations with sparser vegetation, and are characterized by high levels of epinephrine and norepinephrine in several forebrain nuclei. Territorial males emit vocalizations, are typically surrounded by more vegetation than silent males, may have a silent male within their territory, and are denoted by significantly higher levels of norepinephrine in the preoptic area and ventral hypothalamus and dopamine in the amygdala responsible male territorial behaviors. Paternal males brood and guard developing embryos in secluded nest sites that are surrounded by vegetation, not within territories of residential males, and typically not in close proximity of silent males. Paternal brains have significantly higher levels epinephrine and serotonin in the raphe and reticular nuclei indicating the necessity to regulate metabolic processes and stress during the period of prolong paternal care.

An alumina-modified glassy carbon electrode: a robust platform for accurate nimodipine detection in pharmaceutical applications.

Nimodipine (NMP) is a calcium channel blocker known for maintaining blood perfusion, particularly in the brain. Given its importance and widespread applicability, tracking NMP during industrial processes for both pharmaceutical dosage forms and raw material samples is crucial. This article discusses the use of a glassy carbon electrode (GCE) polished with commercial alumina for NMP determination. Atomic force microscopy (AFM) confirmed the presence of residual alumina on the surface of the GCE, and electrochemically active surface area (EASA) analysis demonstrated an enhancement in the active area. The alumina-polished electrode (GCE/AP) exhibited a superior response for NMP, with voltammograms obtained via differential pulse voltammetry (DPV). In this investigation, we employed density functional theory (DFT) calculations to examine the electrochemical characteristics of NMP from a theoretical standpoint. The geometry was optimized by employing the Generalized Gradient Approximation (GGA) functional, BP86, in conjunction with the Def2-TZVPPPD basis set and D3BJ dispersion corrections. To identify potential sites for oxidation and reduction, Fukui indices and dual descriptors were employed. The results indicate that the nitro group is the most probable site for reduction, whereas the dihydropyridine ring displays a proclivity for electrophilic attack. Regarding electroanalysis, two calibration curves were established through consecutive additions of NMP, with linear ranges of 0.20 to 49.0 μmol L-1 and 2.92 to 13.5 μmol L-1, respectively. The theoretical limits of detection (LOD) and quantification (LOQ) were, respectively, 0.06 μmol L-1 and 0.20 μmol L-1 for the first curve, and 4.0 μmol L-1 and 12.0 μmol L-1 for the second curve. Common constituents in pharmaceutical tablets were tested as potential interferents, and GCE/AP showed acceptable anti-interference ability. NMP was successfully quantified in tablet and raw material samples using the novel electrochemical method and High-Performance Liquid Chromatography (HPLC). Statistical analysis revealed no significant differences between the results. This confirms that the GCE/AP sensor was effectively applied to pharmaceutical samples, consistent with findings reported in the literature.

Tocochromanols in the Leaves of Plants in the Hypericum and Clusia Genera

Now under Clusiaceae and Hypericaceae, Clusia and Hypericum were previously categorized under one family until they were divided in 2003 by the APG III system. The Clusia genus is characterized by the presence of tocotrienol derivatives with antiangiogenic properties, and only Hypericum perforatum tocochromanol content has been studied in the Hypericum genus. Twelve species were analyzed: H. aegypticum, H. calycinum, H. empetrifolium, H. lancasteri, H. olympicum f. minus ‘Sulphureum’, H. perforatum, H. xylosteifolium, C. fluminensis, C. minor, C. odorata, C. palmicida, and C. tocuchensis. Plant leaves were analyzed for their tocochromanol (α-, β-, γ-, and δ-tocotrienol and tocopherol) contents using a reverse-phase high-performance liquid chromatography with fluorescent light detector (RP-HPLC-FLD) method. While α-tocopherol (α-T) was present in the highest proportion, the leaves had significant tocotrienol (T3) contents. Following α-T, δ-T3 was present in most Clusia samples, and γ-T3 in most Hypericum samples, except H. olympicum, in which α-T3 followed. C. minor had the highest α-T (112.72 mg 100 g−1) and total tocochromanol (141.43 mg 100 g−1) content, followed by C. palmicida (65.97 and 82.96 mg 100 g−1, respectively) and H. olympicum (α-T 32.08, α-T3 30.68, and total tocochromanols 89.06 mg 100 g−1). The Hypericum genus is a valuable source of tocotrienols, with potential use after purification.

Association between serum carotenoids levels and endometriosis risk: evidence from the National Health and Nutrition Examination Survey

BackgroundThe relationship between serum levels of carotenoids and endometriosis remains largely unknown. The aim of this study is to assess the association between serum levels of major carotenoids (α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin, and trans-lycopene) and the risk of endometriosis in US women.MethodsThe data were obtained from the 2001–2006 National Health and Nutrition Examination Surveys (NHANES), which included a total of 3,636 women aged 20 to 54. Serum levels of α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin, and trans-lycopene were measured using high performance liquid chromatography (HPLC) with photodiode array detection. Endometriosis was defined as self-report. Weighted multivariate logistic regression analyses were conducted to evaluate the associations of the serum levels of the major carotenoids with endometriosis risk. Additionally, restricted cubic spline (RCS) was employed to assess the possibility of nonlinear associations. Finally, subgroup analyses were utilized to estimate the influence of several covariates on the associations.ResultsWeighted multivariate logistic regression analyses showed that, after adjusting for all covariates taken into account, there was a significant association between serum lutein/zeaxanthin levels and reduced risk of endometriosis (Quartile 3 vs. Quartile 1: odds ratio [OR] = 0.62, 95% confidence interval [CI]: 0.42–0.90; Quartile 4 vs. Quartile 1: OR = 0.54, 95% CI: 0.36–0.81, P for trend = 0.001). However, no significant associations of serum levels of other carotenoids with endometriosis were found in multivariable-adjusted models that included all covariates. RCS analysis did not reveal any non-linear relationships. Subgroup analyses indicated that the inverse association between serum lutein/zeaxanthin levels and reduced endometriosis risk was significant only in individuals under 40 years of age, in both White and non-White populations, in smokers, and among those who had ever used oral contraceptives.ConclusionSerum lutein/zeaxanthin levels may offer protective effects against endometriosis in specific subpopulations. Further prospective research is necessary to validate these findings.

Synthesis and Structures of 9,9’‐Bianthryl‐Based Cyclic Dimer and Dinaphtho[c,g]Carbazole via Oxidative Coupling

Abstract9,9′‐Bianthryl‐based cyclic dimer and dinaphtho[c,g]carbazole derivatives were synthesized from a di(2‐anthracenyl)amine derivative via Scholl reactions. The selectivity of annulation sites was regulated by the choice of oxidants. By optimizing reaction conditions with 2,3‐dichloro‐5,6‐dicyano‐p‐benzoquinone (DDQ) and MeSO3H, a cyclic dimer of 9,9′‐bianthryl units featuring a chiral structure was obtained. Enantiomers of the cyclic dimer were successfully resolved by chiral high‐performance liquid chromatography (HPLC). Circular dichroism (CD) spectra of the M,M‐isomer were analyzed using theoretical calculations based on the time‐dependent density functional theory (TD‐DFT) method. The calculations reasonably reproduced the observed CD bands and determined the absolute stereochemistry. Oxidation with FeCl3 gave a dinaphtho[c,g]carbazole derivative, where the 1‐positions of the anthracene units were fused intramolecularly. DFT calculations were further employed to predict the preferential bonding sites of the two 2‐anthryl units leading to the dinaphtho[c,g]carbazole derivative.

Nanofiltration-based purification process for whole-cell transformed prebiotic galactooligosaccharides.

The enrichment of galactooligosaccharides (GOS), synthesized by whole cells of Kluyveromyces marxianus 3551 in a 5.0-L bioreactor, was investigated in this study. The synthesized sugar mixture containing 17.89% (w/w of total carbohydrates) of GOS with 15.57% (w/w of total carbohydrates) of lactose, and 66.54% (w/w of total carbohydrates) monosaccharides as impurities, was subjected to nanofiltration for enrichment of GOS. Three distinct spiral wound membranes, namely, NFPS-01(polysulfone), NFCA-02 (cellulose acetate), and NFPES-03 (polyethersulfone) were tested out of which the NFPES-03 performed the best for fractionation of the GOS mixture. The polyethersulphone membrane (cut-off 400-1000Da) was evaluated at 30℃ and 50℃, at different transmembrane pressures or TMP (15, 20, 25bar) and a combination of high temperature (50℃) and low pressure (15bar) gave the greatest difference in the trisaccharide and disaccharide/monosaccharide rejection percentages, resulting in enrichment of GOS. An analysis of the sugar concentrations in the retentate samples by high-performance liquid chromatography indicated the percentage recovery of GOS in the integrated process to be 88.8%. Measurement of the growth profile of several microbes on the nano-filtered GOS demonstrated its effectiveness as a prebiotic source.

Determination of Bioactive Compounds and Antioxidant Capacity in Leaf and Pulp of Annona muricata

This study focused on analyzing and comparing bioactive compounds, specifically phenolics, in the pulp and leaf of Annona muricata (soursop), a crop highly valued in Latin America for its culinary and traditional uses. Methanolic extractions of leaf and pulp were performed for phytochemical screening, high-performance liquid chromatography (HPLC), and measurements of antioxidant capacity. The results confirmed the presence of 15 phenolic compounds in the leaf and 14 in the pulp; these included phenolic acids and flavonoids. Shikimic acid was the main component identified, constituting 85 mg/g of the dry leaf sample and 17.50 mg/g of the dry pulp. The antioxidant capacity was determined using DPPH and FRAP. The percentages of inhibition were 70.93 and 15.10 in the leaf and pulp, respectively. This work expands our knowledge about the compounds present in A. muricata, which may be partly responsible for the known benefits of this plant for human health and nutrition.

Development of a green and rapid ethanol-based HPLC assay for aspirin tablets and feasibility evaluation of domestically produced bioethanol in Thailand as a sustainable mobile phase

Abstract Despite the growing trend of using ethanol as a greener alternative to hazardous solvents like methanol and acetonitrile in high-performance liquid chromatography (HPLC) analysis, no ethanol-based assay has been developed for aspirin tablets, nor has the potential of domestically produced bioethanol as a mobile phase been explored – until now. This study introduces a novel ethanol-based HPLC assay for aspirin and assesses the feasibility of using locally produced bioethanol. The optimized method, featuring a 40% (v/v) ethanol–water mobile phase adjusted to pH 3.6 with glacial acetic acid, with a 15-cm C18 column at 40°C and UV detection at 237 nm, successfully separated aspirin and its degradation product, salicylic acid, in 5 min. It demonstrated excellent linearity (0.1–0.6 mg·mL−1, r² = 0.9997), sensitivity (LOD = 0.01 mg·mL−1, LOQ = 0.03 mg·mL−1), accuracy, and precision, with no interference from excipients. The method’s performance on commercial aspirin tablets aligned with official pharmacopoeial methods. In a case study using fuel-grade bioethanol (&gt;99.5% purity) derived from sugarcane molasses or cassava from local manufacturers in Thailand, chromatographic and analytical results matched those obtained with imported ethanol, validating its effectiveness. This innovative approach not only reduces costs and dependence on imported solvents but also supports local bio-circular-green economies and promotes greener, more sustainable analytical practices.