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Here, we demonstrate mid‐field 1H NMR spectroscopy combined with chemometrics to be powerful in the classification and authentication of motor oils (MOs). The 1H NMR data were processed with a new algorithm for simultaneous phase and baseline correction, which, for crowded spectra such as those of the refinery products, allowed for more accurate estimation of phase parameters than other literature approaches tested. A principal component analysis (PCA) model based on the unbinned CH3 fingerprint region (0.6–1.0 ppm) enabled the differentiation of hydrocracked and poly‐α‐olefin‐based MOs and was effective in resolving mixtures of these base stocks with conventional base oils. PCA analysis of the 1.0‐ to 1.14‐ppm region enabled the detection of poly (isobutylene) additive and was useful for differentiating between single‐grade and multigrade MOs. Non‐equidistantly binned 1H NMR data were used to detect the addition of esters and to establish discriminant models for classifying MOs by viscosity grade and by major categories of synthetic, semisynthetic, and mineral oils. The performances of four classifiers (linear discriminant analysis [LDA], quadratic discriminant analysis [QDA], naïve Bayes classifier [NBC], and support vector machine [SVM]) with and without PCA dimensionality reduction were compared. In both tasks, SVM showed the best efficiency, with average error rates of ~2.3% and 8.15% for predicting major MO categories and viscosity grades, respectively. The potential to merge spectra collected from different NMR instruments is discussed for models based on spectral binning. It is also shown that small errors in phase parameters are not detrimental to binning‐based PCA models. [ABSTRACT FROM AUTHOR]

Introduction: The prevalence of type 2 diabetes has surged to epidemic proportions and despite treatment administration/adherence, some individuals experience poorly controlled diabetes. While existing literature explores metabolic changes in type 2 diabetes, understanding metabolic derangement in poorly controlled cases remains limited. Objective: This investigation aimed to characterize the urine metabolome of poorly controlled type 2 diabetes in a South African cohort. Method: Using an untargeted proton nuclear magnetic resonance metabolomics approach, urine samples from 15 poorly controlled type 2 diabetes patients and 25 healthy controls were analyzed and statistically compared to identify differentiating metabolites. Results: The poorly controlled type 2 diabetes patients were characterized by elevated concentrations of various metabolites associated with changes to the macro-fuel pathways (including carbohydrate metabolism, ketogenesis, proteolysis, and the tricarboxylic acid cycle), autophagy and/or apoptosis, an uncontrolled diet, and kidney and liver damage. Conclusion: These results indicate that inhibited cellular glucose uptake in poorly controlled type 2 diabetes significantly affects energy-producing pathways, leading to apoptosis and/or autophagy, ultimately contributing to kidney and mild liver damage. The study also suggests poor dietary compliance as a cause of the patient's uncontrolled glycemic state. Collectively these findings offer a first-time comprehensive overview of urine metabolic changes in poorly controlled type 2 diabetes and its association with secondary diseases, offering potential insights for more targeted treatment strategies to prevent disease progression, treatment efficacy, and diet/treatment compliance. [ABSTRACT FROM AUTHOR]

Single-sided time-domain proton magnetic resonance (MR) surface scanners are useful for non-destructive measurements of moisture. A mobile single-sided MR sensor unit employing two concentric ring magnets was constructed for the in situ quantification of moisture in slaked lime plaster used in the outer walls and roofs of heritage architecture. This sensor unit allows for non-destructive measurements of water proton relaxation 1.5 to 13.5 mm beneath the surfaces of walls and roofs. The following laboratory experiments on water-saturated porous slaked lime plaster samples were performed. (i) The porosity (water volume fraction) was measured in approximately eight minutes with a root mean square error of 1.9 vol%. (ii) The fundamental MR-related property (i.e. proton surface relaxivity) needed for the estimation of the pore size distribution was also measured successfully. (iii) The pore volume expansion due to frost damage was successfully detected as a significant change in the transverse relaxation time distribution. These results demonstrate that the portable MR surface scanner is a promising non-destructive testing tool for the maintenance and remediation of heritage architecture made of plaster. [ABSTRACT FROM AUTHOR]

AIM: To observe the differences in the regulatory effects of acupuncture and moxibustion on colonic metabolites and gut microbiota in healthy SD rats. METHODS: A total of 33 healthy SD rats were randomly divided into 3 groups: blank group, acupuncture group, and moxibustion group, with 11 rats in each group. The rats in blank group was placed in a supine position on the treatment table without interventions for 7 consecutive days. In acupuncture group, stainless steel acupuncture needles were used to puncture bilateral Shangjuxu and Tianshu points, which was retained for 15 min, and the intervention was performed for 7 consecutive days. In moxibustion group, mild moxibustion was applied by placing moxa sticks on both sides of Shangjuxu and Tianshu points, approximately 3~5 cm above the skin. The skin temperature was maintained at(45±5)°C for 15 min during each session, and the intervention continued for 7 days. After collecting colon tissues and fecal samples from the rats in each group, proton nuclear magnetic resonance ('H-NMR)technology was utilized to detect the metabolites in colon tissues, and the differential metabolites were screened and identified. Additionally, the abundance and diversity characteristics of intestinal flora, including differential flora, were examined by 16S ribosomal DNA (rDNA) sequencing. RESULTS: The results of metabolomics detection revealed that the levels of histidine, valine and butyric acid in the colons of rats in acupuncture group were significantly higher than those in blank group (P<0. 05). Additionally, the levels of choline and inositol in the colons of rats in moxibustion group showed significant increases 01 or PVO. 05). Furthermore, there was a significant increase in the levels of formic acid and acetic acid in the colons of rats in moxibustion group compared with acupuncture group (P<0. 05). The analysis of the diversity of intestinal flora showed that the Chaol index and abundance-based coverage estimator(ACE)of the intestinal flora in acupuncture group and moxibustion group were significantly increased compared with blank group (PV0. 05). At the phylum and genus levels, the abundance levels of some beneficial bacteria increased, while the abundance levels of some conditional pathogenic bacteria decreased. CONCLUSION: Acupuncture and moxibustion have different effects on the regulation of colonic metabolites and gut microbiota in healthy SD rats. Acupuncture is better at regulating gastrointestinal diseases caused by an imbalance of acid metabolism, while moxibustion is more suitable for metabolic diseases caused by abnormal lipid metabolism. Acupuncture and moxibustion have a beneficial regulatory effect on the intestinal microenvironment. Specifically, acupuncture has the potential to improve gastrointestinal diseases by influencing the structure and abundance of gut microbiota. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to perform a comparative analysis of metabolite levels in serum and milk obtained from cows fed on different concentrate to forage feed ratios. Methods: Eight lactating Holstein cows were divided into two groups: a high forage ratio diet (HF; 80% Italian ryegrass and 20% concentrate of daily intake of dry matter) group and a high concentrate diet (HC; 20% Italian ryegrass and 80% concentrate) group. Blood was collected from the jugular vein, and milk was sampled using a milking machine. Metabolite levels in serum and milk were estimated using proton nuclear magnetic resonance and subjected to qualitative and quantitative analyses performed using Chenomx 8.4. For statistical analysis, Student's t-test and multivariate analysis were performed using Metaboanalyst 4.0. Results: In the principal component analysis, a clear distinction between the two groups regarding milk metabolites while serum metabolites were shown in similar. In serum, 95 metabolites were identified, and 13 metabolites (include leucine, lactulose, glucose, betaine, etc.) showed significant differences between the two groups. In milk, 122 metabolites were identified, and 20 metabolites (include urea, carnitine, acetate, butyrate, arabinitol, etc.) showed significant differences. Conclusion: Our results show that different concentrate to forage feed ratios impact the metabolite levels in the serum and milk of lactating Holstein cows. A higher number of metabolites in milk, including those associated with milk fat synthesis and the presence of Escherichia coli in the rumen, differed between the two groups compared to that in the serum. The results of this study provide a useful insight into the metabolites associated with different concentrate to forge feed ratios in cows and may aid in the search for potential biomarkers for subacute ruminal acidosis. [ABSTRACT FROM AUTHOR]

Background: We aimed to evaluate the accuracy of genotyping of Leishmania species by the spliced leader mini-exon gene. Methods: Suspected leishmaniasis patients, referred to Masieh Daneshvary Hospital, Tehran, Iran were included from May 2017 to September 2021. The Leishmania species were genotyped by PCRRFLP based on the SL mini-exon gene and the ITS1 region of SSU-rRNA gene and compared with the sequencing results. The expressed metabolites of metacyclic promastigotes were evaluated by Proton nuclear magnetic resonance (1H-NMR). Results: Out of 66 suspected cases, 36 (54.4%) were positive for Leishmania species based on the PCR assays. In 21 (31.8%) cases, promastigotes grew on culture tubes. Based on the RFLP of SL RNA profile, 13 (19.7%) L. tropica, 9 (13.6%) L. major, 3 (4.5%) L. infantum, and 8 (12.1%) C. fasciculata isolates, isolated from culture media, were identified; however, 3 (4.5%) cases were unidentifiable due to the low number of parasites. Seventeen metabolites were expressed by the metacyclic forms of L. major, L. tropica and C. fasciculata isolates. The top differential metabolites expressed more in C. fasciculata were FAD, p-Methoxybenzyl alcohol and S-b-G-5, 5-G-b-S (A = CH2) (P<0.005) whereas Veratryl glycerols and D-(+)-Mannose were significantly increased in L. major and Betulin, LTyrosine in L. tropica (P<0.01). Conclusion: The invaluable techniques such as sequencing and 1H-NMR confirmed the results of genotyping of Leishmania species based on the SL mini-exon gene. SL mini exon gene can be used as a diagnostic tool to differentiate various Leishmania genotypes and detect contamination of culture media with C. fasciculata. [ABSTRACT FROM AUTHOR]

Endophytic Diaporthe is a fungal genus having an extensive distribution in plant hosts. It is known as a valuable source of bioactive metabolites with potent biological properties. In the present study, proton nuclear magnetic resonance (1H-NMR) coupled with multivariate analysis (MVA) was employed to discriminate the chemical profile of Diaporthe fraxini cultured under different growth conditions. Cholinesterase inhibitory assay was performed to assess the activity of the fungal extracts against acetylcholinesterase and butyrylcholinesterase. Discriminant metabolites responsible for the chemical variations were successfully obtained using 1H-NMR-based metabolomics approach. Principal component analysis showed a clear discrimination of the fungal extracts of D. fraxini grown under different conditions. Cholinesterase inhibitory activity studies revealed the potential of supplemented cultured fungal extract of D. fraxini as a source of cholinesterase inhibitor. [ABSTRACT FROM AUTHOR]

Honey is a nourishing and natural food product that is widely favored by a diverse group of consumers. Proton Nuclear Magnetic Resonance (1H NMR) is a powerful tool for quantitative analysis of honey and plays a crucial role in ensuring its quality. The 1H NMR technique necessitates the utilization of multivariate calibration models to facilitate the quantitative analysis of key compounds present in honey. However, maintaining consistent measurement conditions across different years is scarcely possible, which can significantly impact the distribution of training and test spectra, ultimately leading to reduced performance of predictive models. Unsupervised domain adaptation (UDA) methods have gained considerable attention for their ability to match distribution differences between the labeled source spectra and the unlabeled target spectra without costly annotation. To enhance the quantitative model generalizability on honey from different years, we propose a UDA method known as partial least squares subspace and optimal transport-based UDA (PLSS-OT-UDA). This approach eliminates distribution differences between the source subspace and target subspace via partial least squares (PLS) dimensionality reduction and OT. Firstly, the optimal latent variable weight matrix from the source domain (i.e., labeled 1H NMR data in 2017) is extracted with PLS. Next, the dimension of both source and target domains (i.e., unlabeled 1H NMR data in 2018) is reduced and their corresponding subspaces are obtained with weight matrix of the source domain. Finally, OT is then employed to align the distribution of the source and target domains within the subspace. Experimental results on the honey dataset demonstrate that the PLSS-OT-UDA outperforms traditional methods, including transfer component analysis (TCA), optimal transport for domain adaptation (OTDA), domain adaptation based on principal component analysis and optimal transport (PCA-OTDA), and subspace alignment (SA), with respect to generalization performance on three components: baume degree, sugar content, and water content. • Utilizing 1H NMR and PLSS-OT-UDA for robust quantitative assessment of honey. • PLSS-OT-UDA aligns source and target subspaces through PLS and OT. • Minimizing Yearly Data Discrepancies to Improve Model Generalization Reliability. • Exhibited superior generalization in relation to baume degree, sugar content, and water content. [ABSTRACT FROM AUTHOR]

In preparation for implementing the Nitric-Glycolic (NG) acid flowsheet for the Savannah River Site (SRS) Liquid Waste System (LWS), analytical methods for determining glycolate at low concentration, below 20 mg/L in radioactive samples, were developed to support system management and safety. To accommodate the wide range of LWS matrix conditions, two alternative methods were developed, refined, and demonstrated for glycolate analysis in radioactive waste samples: ion chromatography (IC) and a proton nuclear magnetic resonance (H NMR). Investigators validated IC and H NMR methods for glycolate analysis, defined the range of applicability, and demonstrated key supporting analytical protocols. The deployed IC method is applicable in low to moderate ionic strength samples and requires sample pretreatment using a Dionex OnGuard II H+ cartridge. The deployed H NMR method is more labor intensive but provides options for a broader range of matrices. Based on the results, high quality glycolate analysis of the Defense Waste Processing Facility (DWPF) condensate in Tank 22 is feasible by IC down to approximately 12 mg/L. Using H NMR, glycolate may be determined to 8 mg/L or lower depending on the run time with the potential for broader applicability of the method to higher ionic strength conditions in other tanks of the SRS LWS. [ABSTRACT FROM AUTHOR]

The growing consensus links exposure to fine particulate matter (PM 2.5) with an increased risk of respiratory diseases. However, little is known about the additional effects of particulate matter on brainstem function in allergic rhinitis (AR). Furthermore, it is unknown to what extent the PM 2.5 -induced effects in the brainstem affect the inflammatory response in AR. This study aimed to determine the effects, mechanisms and consequences of brainstem neural activity altered by allergenic stimulation and PM 2.5 exposure. Using an AR model of ovalbumin (OVA) elicitation and whole-body PM 2.5 exposure, the metabolic profile of the brainstem post-allergen stimulation was characterized through in vivo proton magnetic resonance imaging (1H-MRS). Then, the transient receptor potential vanilloid-1 (TRPV1) neuronal expression and sensitivity in the trigeminal nerve in AR were investigated. The link between TRPV1 expression and brainstem differential metabolites was also determined. Finally, we evaluated the mediating effects of brainstem metabolites and the consequences in the brain-spleen axis in the inflammatory response of AR. Exposure to allergens and PM 2.5 led to changes in the metabolic profiles of the brainstem, particularly affecting levels of glutamine (Gln) and glutamate (Glu). This exposure also increased the expression and sensitivity of TRPV1+ neurons in the trigeminal nerve, with the levels of TRPV1 expression closely linked to the brainstem metabolism of Glu and Gln. Moreover, allergens increased the activity of p38, while PM 2.5 led to the phosphorylation of p38 and ERK, resulting in the upregulation of TRPV1 expression. The brainstem metabolites Glu and Gln were found to partially mediate the impact of TRPV1 on AR inflammation, which was supported by the presence of pro-inflammatory changes in the brain-spleen axis. Brainstem metabolites are altered under allergen stimulation and additional PM 2.5 exposure in AR via sensitization of the trigeminal nerve, which exacerbates the inflammatory response via the brain-splenic axis. [ABSTRACT FROM AUTHOR]

Accurate chemical shift and coupling constant for 1- and 2-naphthyl derivatives were decipher by iterative full spin analysis. Each of the seven magnetically nonequivalent H2–H8 atoms in 1-naphthyl derivatives, or of the H1, H3–H8 atoms in 2-naphthyl derivatives were unambiguously identified by analyzing their intra- and inter-ring coupling constants at 300 MHz and by two-dimensional homo- and heteronuclear experiments at 750 MHz. 13C chemical shifts were also determined during this study, from where some literature ambiguities were resolved using long-range C–H correlations at 750 MHz. The complete proton nuclear magnetic resonance parameters are herein ascribed for the first time. [ABSTRACT FROM AUTHOR]

The brain-gut axis is increasingly recognized as an important contributing factor in the onset and progression of severe mental illnesses such as schizophrenia spectrum disorders and bipolar disorder. This study investigates associations between levels of faecal metabolites identified using 1H-NMR, clinical parameters, and dietary components of forty-two individuals diagnosed in a transdiagnostic approach to have severe mental illness. Faecal levels of the amino acids; alanine, leucine, and valine showed a significant positive correlation with psychiatric symptom severity as well as with dairy intake. Overall, this study proposes a diet-induced link between the brain-gut axis and the severity of psychiatric symptoms, which could be valuable in the design of novel dietary or therapeutic interventions to improve psychiatric symptoms. [ABSTRACT FROM AUTHOR]

Moisture content in coal powder is a critical index because it controls the difficulty of coal handling and ultimately its combustion efficiency in coal-fired power plants. A unilateral proton nuclear magnetic resonance (NMR) scanner was applied in a laboratory to nondestructively quantify moisture content in powdered samples of brown and subbituminous coals. Due to the open geometry of the sensor unit, the scanner allows the nondestructive moisture quantification of a portion several millimeters below the surface of a large sample. Proton transverse relaxation was measured by the unilateral NMR scanner, and obtained moisture content values were compared with those by a conventional bilateral NMR apparatus. The comparison showed reasonable agreement with a root mean square residual of 4.1 wt.%H2O for a moisture content range of > 12 wt.%H2O (wet basis). This moisture-quantification performance by unilateral NMR is sufficient for the quality control of wet coal having a critical value of approximately 30 wt.%H2O in terms of the handling property (flow-ability). Because unilateral NMR requires no specific sample preparation, such as sample insertion into tubes, the system is potentially applicable to in-situ nondestructive monitoring of the coal moisture in power plants to contribute to improved efficiency of handling and combustion. [ABSTRACT FROM AUTHOR]

This study characterized the lipopeptide biosurfactants produced by lactic acid bacteria isolated from milk and milk products, in addition to their effect on maize plant growth. The oil displacement test was performed as a primary screening method to select the BS producing bacteria. The strain LM5.2 had the maximum emulsification index of 45.1 ± 3, reduced the surface tension to 32.98 ± 0.23% among all the isolates, and efficiently produced 945.26 ± 4.62 mg/l of biosurfactants within 48 h in MRS broth under the optimum conditions. The isolate LM5.2 was identified using physiochemical tests and 16S rRNA gene sequencing as E. faecium. The biosurfactant was purified by TLC and identified as lipopeptide-like iturins and surfactins based on Rf values. Mass spectroscopy, NMR, and FTIR analysis also confirmed the biosurfactant’s identity as the derivatives of iturin and surfactin. In vitro biosurfactant application significantly enhanced seedling growth at an optimal concentration of 450 µg/ml. Plant treatment (pot experiment) with E. faecium LM5.2 significantly promoted Zea mays growth compared to the control. To the best of our knowledge, this is the first report of lipopeptide biosurfactant production by E. faecium. Moreover, the study also showed that the biosurfactant and biosurfactant-producing E. faecium LM5.2 could be an eco-friendly plant growth-promoting agent. [ABSTRACT FROM AUTHOR]

Purpose: Choline is an essential nutrient for fetal and infant growth and development. Parenteral nutrition used in neonatal care lack free choline but contain small amounts of lipid-bound choline in the form of phosphatidylcholine (PC). Here, we examined the longitudinal development of serum free choline and metabolically related compounds betaine and methionine in extremely preterm infants and how the concentrations were affected by the proportion of parenteral fluids the infants received during the first 28 postnatal days (PNDs). Methods: This prospective study included 87 infants born at gestational age (GA) < 28 weeks. Infant serum samples were collected PND 1, 7, 14, and 28, and at postmenstrual age (PMA) 32, 36, and 40 weeks. The serum concentrations of free choline, betaine, and methionine were determined by 1H NMR spectroscopy. Results: The median (25th–75th percentile) serum concentrations of free choline, betaine, and methionine were 33.7 (26.2–41.2), 71.2 (53.2–100.8), and 25.6 (16.4–35.3) µM, respectively, at PND 1. The choline concentration decreased rapidly between PND one and PND seven [18.4 (14.1–26.4) µM], and then increased over the next 90 days, though never reaching PND one levels. There was a negative correlation between a high intake of parenteral fluids and serum-free choline. Conclusion: Circulating free choline in extremely preterm infants is negatively affected by the proportion of parenteral fluids administered. Trial registration: ClinicalTrials.gov Identifier NCT02760472, April 29, 2016, retrospectively registered. [ABSTRACT FROM AUTHOR]

In this study, quantative nuclear magnetic resonance (qNMR) method was used to determine the content of rosuvastatin in tablet. Linearity, range, limit of detection (LOD), limit of quantification (LOQ), accuracy, and precision were determined in validation study of rosuvastatin. Furthermore, validation study of rosuvastatin was performed with high performance liquid chromatography (HPLC). Uncertainties of qNMR and HPLC methods were determined using per EURACHEM/CITAC Guide CG 4 (3th edition), quantifying uncertainty in analytical measurement. qNMR and HPLC methods were linear in the ranges of 0.10 - 5.00 mg/mL and 0.001 - 0.0995 mg/mL, respectively and these lineraties indicate very good linearity performance with regression coefficients (R2 value) above > 0.99. Moreover, LOD and LOQ values using qNMR method were observed as 0.25 mg/mL and 0.80 mg/mL, respectively. These values using HPLC method were found as 0.00051 µg/mL and 0.001695 µg/mL, respectively. The strengths and weaknesses of qNMR method and HPLC method were determined with spectral emphasis on the role of identical reference standards in qualitive and quantitative analyses. It was found that qNMR method is simple, efficient, reliable, and accurate method. Moreover, qNMR method is an easy, practical, and useful method for the validation and optimization of rosuvastatin in the tablet. [ABSTRACT FROM AUTHOR]

Since Ba-Ti systems are often used as precursors for ceramics and superconducting systems, it was thought that study of the methanolysis and hydrolysis reactions of such systems would be beneficial. This paper includes the study of hydrolysis and methanolysis of a bimetallic system having an alkaline earth metal (barium) and a transition metal (titanium), Ba{Ti (OPri)6, and Ba{Ti2(OPri)9}2. [ABSTRACT FROM AUTHOR]

Kidney cancer is one of the most frequently diagnosed and the most lethal urinary cancer. Despite all the efforts made, no serum-specific biomarker is currently used in the clinical management of patients with this tumor. In this study, comprehensive high-resolution proton nuclear magnetic resonance spectroscopy (1H NMR) and silver-109 nanoparticle-enhanced steel target laser desorption/ionization mass spectrometry (109AgNPET LDI MS) approaches were conducted, in conjunction with multivariate data analysis, to discriminate the global serum metabolic profiles of kidney cancer (n = 50) and healthy volunteers (n = 49). Eight potential biomarkers have been identified using 1H NMR metabolomics and nine mass spectral features which differed significantly (p < 0.05) between kidney cancer patients and healthy volunteers, as observed by LDI MS. A partial least squares discriminant analysis (OPLS-DA) model generated from metabolic profiles obtained by both analytical approaches could robustly discriminate normal from cancerous samples (Q2 > 0.7), area under the receiver operative characteristic curve (ROC) AUC > 0.96. Compared with healthy human serum, kidney cancer serum had higher levels of glucose and lower levels of choline, glycerol, glycine, lactate, leucine, myo-inositol, and 1-methylhistidine. Analysis of differences between these metabolite levels in patients with different types and grades of kidney cancer was undertaken. Our results, derived from the combination of LDI MS and 1H NMR methods, suggest that serum biomarkers identified herein appeared to have great potential for use in clinical prognosis and/or diagnosis of kidney cancer. [ABSTRACT FROM AUTHOR]

Hence, in this study, the authors aimed to develop a dendrimer‐based imaging agent comprised of poly(ethylene glycol) (PEG)‐citrate, technetium‐99 m (99m Tc), and folic acid. The dendrimer‐G3 was synthesised and conjugated with folic acid, which confirmed by Fourier transform infrared, proton nuclear magnetic resonance, dynamic light scattering, and transition electron microscopy. 2,3‐bis‐(2‐methoxy‐4‐nitro‐5‐sulfophenyl)‐2H‐Tetrazolium‐5‐Carboxanilide cytotoxicity assay kit was used to measure the cellular toxicity of dendrimer. Imaging and biodistribution studies were conducted on the mice bearing tumour. The results showed that the fabricated dendrimer‐G3 has a size of 90 ± 3 nm, which was increased to 100 ± 4 nm following the conjugation with folic acid. The radiostablity investigation showed that the fabricated dendrimers were stable in the human serum at various times. Toxicity assessment confirmed no cellular toxicity against HEK‐293 cells at 0.25, 0.5, 1, 2, 4, and 8 mg/μl concentrations. The in vivo studies demonstrated that the synthesised dendrimers were able to provide a bright SPECT image applicable for tumour detection. In conclusion, the authors' study documented the positive aspects of PEG‐citrate dendrimer conjugated with folic acid as the SPECT contrast agent for breast cancer detection. [ABSTRACT FROM AUTHOR]

The aim of the present study was to synthesize a novel biopolymeric micelle based on punicic acid (PA) and polyacrylamide (PAM) for carrying chemotherapeutic drugs used in prostate cancer treatment. A polymer composite micelle was prepared by chemical conjugation between PAM and PA. The micelles were prepared by self‐assembly via film casting followed by ultrasonication method. The successful production of PAMPA copolymeric micelles was confirmed using FTIR, 1H‐NMR, and TEM. Then, flutamide was loaded in the designed nanomicelles and they were characterized. The cell cytotoxicity of the micelles was studied on PC3 cells of prostate cancer. The prepared nanomicelles showed the particle size of 88 nm, PDI of 0.246, zeta potential of −9 mV, drug loading efficiency of 94.5%, drug release of 85.6% until 10 hours in pH 7.4 and CMC of 74.13 μg/ml. The cell viability in blank nanocarriers was about 70% in PC3 cells at concentration of 25 μM. More significant cytotoxic effects were seen for flutamide loaded micelles at this concentration compared to the free drug. The results suggest that the PAMPA co‐polymeric nanomicelles can be utilized as an effective carrier to enhance the cytotoxic effects of flutamide in prostate cancer. [ABSTRACT FROM AUTHOR]

Aim: This study includes the synthesis and diagnosis of the 3,3’-(disulfanediylbis (methylene))bis(1-(4-bromophenyl)-4-(4-chlorophenyl)azetidin-2-one)2d. Methods: This compound was ready through the reaction of the 3,3’-disulfanediyldipropionic acid with the appropriate 4-bromo-N-(4-chlorobenzylidene) aniline 1d. Results: The structure of those azetidin-2-one was diagnosed on the premise of the spectral data: Infrared (IR); proton nuclear magnetic resonance (¹H-NMR); carbon-13 NMR (13C-NMR); and mass. Conclusion: This work approved the synthesis of 3,3’-(disulfanediylbis(methylene))bis(1-(4-bromophenyl)-4-(4-chlorophenyl)azetidin-2-one) compound from 3,3’-disulfanediyldipropionic acid and appropriate Schiff’s bases using POCl3 and Et3N in CH2Cl2 under N2 atmosphere and characterization of these compound by IR, mass, (2D-NMR experiments) ¹H-NMR, and 13C-NMR spectra. [ABSTRACT FROM AUTHOR]

A sample preparation protocol was developed for honey profiling by proton nuclear magnetic resonance (1H NMR). The honey samples (0.5 g each) were solubilized in 5 ml of oxalate buffer (0.25 mol·l-1, pH 4.3). This solution (1 ml) supplemented with a lock solution (D2O, 0.1 ml) containing 3-(trimethylsilyl) propionic acid D4 sodium salt was used for analysis. The novelty of the proposed method consists in no need for subsequent pH adjustment. The developed method was used for the analysis of 212 French honeys split in seven floral origins (acacia, chestnut tree, scrub, colza, lavender, sunflower and honeydew). A soft independent modelling of class analogy (SIMCA) data treatment was applied to the 1H NMR spectra after a range scale pre-processing. The obtained class distance indicated successful discrimination between the seven floral origins, confirmed by a 100% correct classification when a honey test set was used. The model was applied to commercial mono-floral honeys and the results were fully corroborated by sensory and pollen analyses. [ABSTRACT FROM AUTHOR]

• Volatile and non-volatile metabolites were characterized and analyzed. • Different data fusion and feature extraction methods were investigated. • Common dimension was used to analyze block weights and visualize data. • Mid-level data fusion in the RBF-SVM model achieved 93.33% test set accuracy. • HS-SPME-GC–MS and NMR achieved synergy to obtain higher classification accuracy. The narrow geographical traceability of green tea is both important and challenging. This study aimed to establish multi-technology metabolomic and chemometric approaches to finely discriminate the geographic origins of green teas. Taiping Houkui green tea samples were analyzed by headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry and 1H NMR of polar (D 2 O) and non-polar (CDCl 3). Common dimension, low-level and mid-level data fusion approaches were tested to verify if the combination of several analytical sources can improve the classification ability of samples from different origins. In assessments of tea from six origins, the single instrument data test set results in 40.00% to 80.00% accuracy. Data fusion improved single-instrument performance classification with mid-level data fusion to obtain 93.33% accuracy in the test set. These results provide comprehensive metabolomic insights into the origin of TPHK fingerprinting and open up new metabolomic approaches for quality control in the tea industry. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine whether p-chloroaniline (PCA) is formed in the reactions of sodium hypochlorite (NaOCl) with final rinse chlorhexidine (CHX), QMix (combination of ethylenediaminetetraacetic acid (EDTA), CHX and detergent) and EDTA/CHX solutions by thin-layer chromatography (TLC), proton nuclear magnetic resonance (¹H NMR) and infrared (IR) spectroscopy. Commercially available 5.25% NaOCl solution was mixed with 2% CHX and QMix in 1:1 (v/v) ratio at room temperature. Furthermore, 2% CHX was associated with 17% EDTA under the same experimental conditions. The obtained solutions were evaluated qualitatively for color changing, precipitate and/or bubble formation and analyzed by TLC chromatography. The association products were investigated by spectroscopic (¹H NMR and IR) methods in order to determine whether they contain PCA. It was found that interactions between NaOCl/CHX and CHX/EDTA led to forming of brown and white precipitate. When NaOCl was mixed with QMix, an orange-brown precipitate was formed. PCA was not detected as a product of the reactions between NaOCl and final rinse solutions of CHX, QMix and EDTA/CHX association. [ABSTRACT FROM AUTHOR]

Methacrylated hyaluronic acid (MeHA) has been used extensively in tissue engineering and drug delivery applications. The degree of methacrylation (DM) of HA impacts hydrogel crosslinking, which is of pivotal importance for cell interactions. The methacrylation reaction occurs over several hours, and DM is currently assessed post reaction and after dialysis of the solution, using nuclear magnetic resonance (1H NMR) data. Thus, there is little control over exact DM in a specific reaction. Here, infrared (IR) spectroscopy in attenuated total reflection (ATR) mode was investigated as an alternate modality for assessment of the DM of HA hydrogels, including during the reaction progression. Attenuated total reflection is a low-cost technique that is widely available in research and industry labs that can be used online during the reaction process. Strong correlations were achieved with IR-derived peak heights from dialyzed and lyophilized samples at 1708 cm−1 (from the methacrylic ester carbonyl vibration), and 1H NMR values (R = 0.92, P = 6.56E-11). Additional IR peaks of importance were identified using principal component analysis and resulted in significant correlations with the 1H NMR DM parameter: 1454 cm−1 (R = 0.85, P = 2.81E-8), 1300 cm−1 (R = 0.95, P = 4.50E-14), 950 (R = 0.85, P = 3.55E-8), 856 cm−1 (R = 0.94, P = 1.20E-12), and 809 cm−1 (R = 0.93, P = 3.54E-12). A multiple linear regression model to predict 1H NMR-derived DM using the 1708, 1300, and 1200 cm−1 peak heights as independent variables resulted in prediction with an error of 3.2% using dialyzed and lyophilized samples (P < 0.001). Additionally, a multilinear regression model to predict the DM in undialyzed liquid MeHA samples obtained during the reaction process using similar peak height positions as independent variables resulted in a prediction error of 0.81% (P < 0.05). Thus, IR spectroscopy can be utilized as an alternate modality to 1H NMR for quantification of the DM of MeHA while sampling either on-line during the methacrylation reaction as well as in post-lyophilized products. This could greatly simplify workflow for tissue engineering and other applications. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 72-year-old non-atopic woman showing contact allergy to electrocardiogram electrodes caused by acrylic acid without sensitivity to methacrylates and ethyl cyanoacrylate. The amounts of acrylic acid were determined to be 290-fold and 72-fold in the hydrogel and the outer annular non-adhesive/adhesive of the foam. The study led to the conclusion that acrylic acid does not always cross-react with the methacrylates and ethyl cyanoacrylate

Methyl itaconate–anthracene adducts (MIAs) were previously introduced as chiral derivatizing agents (CDAs) for the determination of chiral secondary alcohols. In this study, they were further employed with chiral primary amines to assign their absolute configuration. Each chiral amine compound was linked to the (R)- and (S)-MIAs through amidation to obtain diastereomeric amides in moderate yield. The modified Mosher's method was applied, where the difference in chemical shift (Δ δ SR = δ H S −MIA-amide – δ H R −MIA-amide) values of each substituent of the chiral amine adducts was utilized to validate the capability of MIAs as CDAs. Finally, the proposed model was successfully achieved, and the MIAs were proven effective for the determination of the absolute configuration of chiral amines. [Display omitted] • Methyl itaconate-anthracene adducts were employed to assign the absolute configuration of chiral primary amines. • The DFT study was conducted to confirm the molecular conformations of the derived chiral MIA-Amides. • The proposed model was validated using various chiral primary amines. [ABSTRACT FROM AUTHOR]

BACKGROUND Java tea is a well-known herbal infusion prepared from the leaves of Orthosiphon stamineus ( OS). The biological properties of tea are in direct correlation with the primary and secondary metabolite composition, which in turn largely depends on the choice of drying method. Herein, the impact of three commonly used drying methods, i.e. shade, microwave and freeze drying, on the metabolite composition and antioxidant activity of OS leaves was investigated using proton nuclear magnetic resonance ( 1H NMR) spectroscopy combined with multivariate classification and regression analysis tools. RESULTS A total of 31 constituents comprising primary and secondary metabolites belonging to the chemical classes of fatty acids, amino acids, sugars, terpenoids and phenolic compounds were identified. Shade-dried leaves were identified to possess the highest concentrations of bioactive secondary metabolites such as chlorogenic acid, caffeic acid, luteolin, orthosiphol and apigenin, followed by microwave-dried samples. Freeze-dried leaves had higher concentrations of choline, amino acids leucine, alanine and glutamine and sugars such as fructose and α-glucose, but contained the lowest levels of secondary metabolites. CONCLUSION Metabolite profiling coupled with multivariate analysis identified shade drying as the best method to prepare OS leaves as Java tea or to include in traditional medicine preparation. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A feasibility study to predict antimicrobial and antioxidant activity properties of propolis extracts using 700-MHz ¹H-NMR spectra and multivariate regression data analysis is presented. The study was conducted with thirty-five propolis samples to develop a rapid and reliable method for the evaluation of their quality. The extracts have been evaluated by measuring phenolic and flavonoid contents; the antioxidant activity; and the antimicrobial activity. The obtained spectral data were submitted to multivariate calibration (partial least squares (PLS) and orthogonal partial least squares (OPLS)) to correlate the relative intensity and position of NMR resonance peaks with the metabolites contents and biological activities. The developed PLS and OPLS model were successfully applied to the determination of the target properties for proof of the concept. The OPLS observed vs. predicted properties plots indicate the absence of systematic errors with determination coefficients between the ranges 0.7207 to 0.9990. Up to 86.1% of explication of variation in the spectral data and 99.9% in the measured properties were attained with 88.6% of prediction capabilities in the best case (S. mutans activity) according to the cross-validation procedure. The figures of merit of the developed PLS and OPLS methods were evaluated and compared as well. [ABSTRACT FROM AUTHOR]

The effect of smoking using liquid smoke flavourings on the hydrolysis and oxidation of European sea bass lipids during in vitro digestion was investigated. The techniques used were 1 H NMR and SPME-GC/MS. The former proved that liquid smoking does not influence the extent of lipolysis, but prevents those lipid oxidation reactions that occur during in vitro digestion of unsmoked samples, giving rise to cis,trans -conjugated dienes associated with hydroperoxy/hydroxy groups. SPME-GC/MS corroborated the results obtained by 1 H NMR in relation to the antioxidant effect of smoking under gastrointestinal conditions. Smoked sea bass digests showed lower abundances of volatile oxidation markers derived from omega-3 and omega-6 lipids than unsmoked ones. Moreover, the lowest values were found in the digests of sea bass samples smoked with the flavouring showing the highest phenolic content. For the first time, the bioaccessibility of smoke flavouring components was evidenced, some of them well-known for displaying antioxidant activity. [ABSTRACT FROM AUTHOR]

Farmed European sea bass ( Dicentrarchus labrax) fillets were smoked with three commercial smoke flavorings. Unsmoked and smoked fillets were submitted to oxidative conditions to study their oxidative stability. To this aim, at regular intervals of time under oxidative conditions, their lipids were extracted and studied by Fourier transform mid-infrared spectroscopy (FTIR) and Proton nuclear magnetic resonance (1H NMR). Both kinds of spectra provide markers referred to the beginning and extension of the lipid degradation and of the formation of new compounds resulting from the oxidation process. Obtaining these data from FTIR is easier, simpler, and quicker than it is from 1H NMR, but this latter technique provides, simultaneously, additional interesting information about the sample. The increase of the oxidative stability of sea bass fillets as a consequence of smoking is proved, as well as the influence on this increase of the concentration of certain phenolic smoke components in the fillets. Practical applications: Farmed European sea bass is widely available in the market, in some occasions the supply being greater than the demand. This study could be very interesting for the seafood industry, because smoking of sea bass fillets with smoke flavorings not only extends their shelf-life, but also provides them with special sensory characteristics, diversifying its presence in the market as a new ready-to-eat product. Nevertheless, it must be taken into account that not all the smoke flavorings show the same effect on fish. This study demonstrates that the smoke flavoring composition and its application method have a great influence on the oxidative stability of smoked sea bass fillets. A study of the lipid oxidative stability of unsmoked and smoked sea bass fillets with three different commercial smoke flavorings was undertaken. To this aim, unsmoked and smoked sea bass fillets were submitted to oxidative conditions and their lipids were extracted and analyzed by Fourier transform infrared spectroscopy (FTIR) and Proton nuclear magnetic resonance (1H NMR) periodically. [ABSTRACT FROM AUTHOR]

Study Question: Does investigation of metabolic perturbations in endometrial tissue of women with dormant genital tuberculosis (GTB) during the window of implantation (WOI) assist in improving the understanding of endometrial receptivity?Summary Answer: In dormant GTB cases significant alterations in endometrial tissue metabolites occur, largely related to energy metabolism and amino acid biosynthesis in dormant GTB cases.What Is Known Already: As an intracellular pathogen, Mycobacterium tuberculosis strongly influences the metabolism of host cells causing metabolic dysregulation. It is also accepted that dormant GTB impairs the receptive status of the endometrium. Global metabolic profiling is useful for an understanding of disease progression and distinguishing between diseased and non-diseased groups.Study Design, Size, Duration: Endometrial tissue samples were collected from patients reporting at the tertiary infertility care center during the period September 2011-March 2013. Women having tested positive for GTB were considered as the study group (n = 24). Normal healthy women undergoing sterilization (n = 26) and unexplained infertile women with repeated IVF failure (n = 21) volunteered to participate as controls.Participants/materials, Setting, Methods: Endometrial tissue samples were collected 6-10 days after confirmation of ovulation. PCR and BACTEC-460 culture were used for diagnosing GTB. Proton nuclear magnetic resonance (1H NMR) spectra of tissue were recorded using a 700 MHz Bruker Avance AV III spectrometer. Following phase and baseline correction of all NMR spectra by Bruker Topspin 2.1 software, spectral peak alignment of the data was performed. Multivariate analysis was applied to all spectra and individual metabolites identified and multiple correlation analysis was performed.Main Results and the Role Of Chance: Leucine, isoleucine, acetate, lactate, glutamate, glutamine, methionine, lysine, creatine, glycogen, glycine, proline and choline were found to be significantly increased (P < 0.05) in endometrial tissue of women with dormant GTB compared with unexplained infertile women with repeated implantation failure. Valine, citrate, succinate and aspartate were also observed to be significantly up-regulated (P < 0.01). Furthermore, a significant decrease in glucose (P < 0.05), threonine (P < 0.05), tyrosine (P < 0.01) and phenylalanine (P < 0.0001) was observed in women with dormant GTB. Pearson's correlation analysis between the expression of various endometrial receptivity markers and metabolites showed a significant negative correlation (-0.236 to -0.545, P < 0.05). Also, the metabolites were positively correlated with endometrial receptivity markers (0.207 to 0.618, P < 0.05).Limitations, Reasons For Caution: It is often difficult to diagnose dormant GTB because it tends to exist without any clinical signs or symptoms. In addition, the diagnosis of GTB by culture remains a challenge due to low detection rates and its paucibacillary nature. Testing for prostate-specific antigen or the Y chromosome in order to account for the possible influences of recent exposure to semen on endometrial metabolism would be important.Wider Implications Of the Findings: The metabolic changes associated with the dormant tubercle infection are of potential relevance to clinicians for the treatment of dormant GTB-related infertility.Study Funding/competing Interests: Government of India, Indian Council of Medical Research. There are no conflicts of interest. [ABSTRACT FROM AUTHOR]

Two simple fingerprinting methods, flow-injection coupled to ultraviolet spectroscopy and proton nuclear magnetic resonance, were used for discriminating betweenAurantii fructus immaturusandFructus poniciri trifoliatae immaturus. Both methods were combined with partial least-squares discriminant analysis. In the flow-injection method, four data representations were evaluated: total ultraviolet absorbance chromatograms, averaged ultraviolet spectra, absorbance at 193, 205, 225, and 283 nm, and absorbance at 225 and 283 nm. Prediction rates of 100% were achieved for all data representations by partial least-squares discriminant analysis using leave-one-sample-out cross-validation. The prediction rate for the proton nuclear magnetic resonance data by partial least-squares discriminant analysis with leave-one-sample-out cross-validation was also 100%. A new validation set of data was collected by flow-injection with ultraviolet spectroscopic detection two weeks later and predicted by partial least-squares discriminant analysis models constructed by the initial data representations with no parameter changes. The classification rates were 95% with the total ultraviolet absorbance chromatograms datasets and 100% with the other three datasets. Flow-injection with ultraviolet detection and proton nuclear magnetic resonance are simple, high throughput, and low-cost methods for discrimination studies. [ABSTRACT FROM AUTHOR]

The impact of different hydration levels, on gelatinization of potato starch (PS), rice starch (RS) and a 1:1 blend thereof, was investigated by differential scanning calorimetry and related to nuclear magnetic resonance proton distributions of hydrated samples, before and after heating. At 20% or 30% hydration, the visual appearance of all samples was that of a wet powder, and limited, if any, gelatinization occurred upon heating. At 30% hydration, changes in proton distributions were observed and related to plasticization of amorphous regions in the granules. At 50% hydration, the PS–RS blend appeared more liquid-like than other hydrated samples and showed more pronounced gelatinization than expected based on additive behavior of pure starches. This was due to an additional mobile water fraction in the unheated PS–RS blend, originating from differences in water distribution due to altered stacking of granules and/or altered hydration of PS due to presence of cations in RS. [ABSTRACT FROM AUTHOR]

• FT-IR, 1H NMR and zeta-potential analysis are potent techniques for reaction tracking. • Formation of browning color products followed a zero-order kinetic regression. • Browning indicators exhibited large positive correlations with antioxidant activities. • Antioxidant activities of MRPs were dependent on initial solution pH. • MRPs have dual function with forming protective layer and delaying fish oil oxidation. Maillard reaction products (MRPs) between chitosan and various sugars with enhanced antioxidant activity were previously produced. However, few reports address the chitosan and corn syrup solids system that has been successfully used to encapsulate nutraceutical oils. Maillard reaction is pH-responsive, the influence of solution pH on the formation kinetic and antioxidant activity of MRPs was therefore evaluated in this work. FT-IR and zeta-potential results confirmed the formation of MRPs between chitosan and corn syrup solids. Possible Amadori compounds signals were observed clearly in the 1H NMR spectrum. Brown color development depended on initial solution pH, following a zero-order kinetic regression. Antioxidant activity of reaction products was higher than the native system and increased with an increase in the initial pH of the solution. Developed MRPs with a dual function as antioxidant and encapsulant can possibly be used to protect emulsified oil from oxidation. [ABSTRACT FROM AUTHOR]

Several studies have suggested that plants are potential sources of bioactive compounds. Phyllanthus is a plant genus that has been used in traditional medicine due to its phytomedicinal metabolites content. The variation between two Phyllanthus species ( P. niruri and P. urinaria ) was studied using proton nuclear magnetic resonance ( 1 H NMR) combined with multivariate data analysis (MVDA). The total phenolic content (TPC), DPPH radical scavenging activity and α-glucosidase inhibitory activity of the Phyllanthus species were also evaluated and correlated with their phytochemical constituents at different growth stages (8, 10 and 12 weeks) using partial least square regression (PLS). Principal component analysis (PCA) and PLS indicated separation between the two species based on the identified metabolites and the screened bioactivities. A comparison of the two species indicated that P. urinaria was separated from P. niruri due to its larger quantity of fatty and amino acids, choline, phyllanthin and sucrose. However, P. niruri contained higher quantities of hypophyllanthin and phenolic compounds. The loading column plot, which was used to compare the P. niruri at different growth stages, indicated that the eight-week-old plant contained a higher amount of fatty acids, amino acids (leucine and alanine), phyllanthin and choline. The dominant substances in the P. niruri at 10 weeks of growth by PC1 were identified as hypophyllanthin, malic acid, sucrose, and identified phenolics. The 12 week sample was differentiated by its higher sugars contents as well as malic acid and leucine. The harvested samples of both Phyllanthus species at ten weeks of age exhibited significant bioactivities with the highest content and number of metabolites. [ABSTRACT FROM AUTHOR]

Studies of interstitial hydrogen diffusion play a key role in understanding of fundamental properties of hydrogen storage materials since the activation energy required to jump from one interstitial site to another affects both the hydrogen sorption kinetics and the desorption temperature. Nuclear magnetic resonance is a very effective tool to study hydrogen diffusivity, jump frequency etc. but it cannot describe the microscopic hydrogen migration processes. From this perspective theoretical studies are very helpful and complement the experiment, however, the results depend on the quality of calculations. Here we provide a brief overview of our most recent results of both theoretical (DFT) and experimental ( 1 H NMR) studies of hydrides of disordered Ti–V–Cr alloys and a theoretical study of hydrogen diffusion in magnesium. [ABSTRACT FROM AUTHOR]

Dissolved iron (dFe) and organic dFe-binding ligands were determined in San Francisco Bay, California by competitive ligand exchange adsorptive cathodic stripping voltammetry (CLE-ACSV) along a salinity gradient from the freshwater endmember of the Sacramento River (salinity < 2) to the mouth of the estuary (salinity > 26). A range of dFe-binding ligand classes was simultaneously determined using multiple analytical window analysis, involving titrations with multiple concentrations of the added ligand, salicylaldoxime. The highest dFe and ligand concentrations were determined in the low salinity end of the estuary, with dFe equal to 131.5 nmol L − 1 and strong ligand (log K F e L , F e ′ cond ≥ 12.0) concentrations equal to 139.5 nmol L − 1 . The weakest ligands (log K F e L , F e ′ cond < 10.0) were always in excess of dFe in low salinity waters, but were rapidly flocculated within the estuary and were not detected at salinities greater than 7. The strongest ligands (log K F e L , F e ′ cond > 11.0) were tightly coupled to dFe throughout the estuary, with average excess ligand concentrations ([L]–[dFe]) equal to 0.5 nmol L − 1 . Humic-like substances analyzed via both CLE-ACSV and proton nuclear magnetic resonance in several samples were found to be a significant portion of the dFe-binding ligand pool in San Francisco Bay, with concentrations ranging from 559.5 μg L − 1 to 67.5 μg L − 1 in the lowest and highest salinity samples, respectively. DFe-binding ligands and humic-like substances were also found in benthic boundary layer samples taken from the shelf near the mouths of San Francisco Bay and Eel River, suggesting estuaries are an important source of dFe-binding ligands to California coastal shelf waters. [ABSTRACT FROM AUTHOR]

Farmed European sea bass ( Dicentrarchus labrax) fillets were salted by two methods, brine- and dry-salting. Both salted and unsalted fillets were submitted to thermo-oxidative conditions in order to study the evolution of their lipids and their oxidative stability. Lipids were extracted and studied by proton nuclear magnetic resonance (1H NMR). This technique allowed the evolution of the molar percentages of the different kinds of acyl groups (omega-3, docosahexaenoic, eicosapentaenoic, diunsaturated omega-6, and omega-1) to be followed. In addition, the formation of secondary oxidation compounds, such as aldehydes (alkanals, trans-2-alkenals, trans,trans-2,4-alkadienals), could be monitored and quantified by means of this technique, providing information about the oxidative status of the sea bass fillets. No primary oxidation compounds were detected. Moreover, the concentrations of 1,2-diglycerides and phosphatidylcholine were determined. Equations for all the mentioned quantitative determinations were proposed. It was evidenced that the use of salting methods did not provoke the immediate oxidation of sea bass lipids, but reduced their oxidative stability, this effect being more pronounced in dry-salting. Although oxidation began earlier in brine-salted samples than it did in unsalted ones, these latter reached a degradation level of a similar order to that of the brine-salted samples after a certain period of time under the degradative conditions. Practical applications: The results of this study will be useful for optimizing the conditions of European sea bass salting processes, in order to minimize possible lipid oxidation. This is of great importance for sectors of the seafood industry, which focus on this and other fish species with similar lipid content and acyl group proportions, and which are interested in providing high quality food products. The information given by 1H NMR, a rapid and non-destructive method compared with other conventional chemical ones, is very valuable for other researchers who also study fish lipid oxidation processes. The study of the effect of brine- and dry-salting on the lipid oxidative stability of European sea bass ( Dicentrarchus labrax) fillets submitted to thermo-oxidative conditions (50°C and aeration) was carried out by means of proton nuclear magnetic resonance (1H NMR). [ABSTRACT FROM AUTHOR]

The major compound inCordyceps militaris(C. militaris), cordycepin, has been known to have a variety of pharmacological properties. The cordycepin concentration in artificially cultivated fruiting bodies ofC. militariswas determined using quantitative1H nuclear magnetic resonance spectroscopy (NMR). The results were compared with a high performance liquid chromatography (HPLC) method. There were no statistically significant differences in the cordycepin concentration by the two methods. Validation of each method was performed in terms of linearity, limit of detection, limit of quantification, intra- and inter-day precision, repeatability, stability, and accuracy. Better inter-day precision, repeatability, stability, and accuracy were obtained by NMR than by HPLC. These results show that NMR is an alternative to HPLC for the determination of cordycepin inC. militarisfruiting bodies. [ABSTRACT FROM PUBLISHER]

Abstract: Proton Nuclear Magnetic Resonance (1H NMR) spectroscopy was employed to study the lipids of farmed and wild European sea bass (Dicentrarchus labrax). This technique provided a great deal of detailed information on sea bass lipids composition and, once the spectra signals have been assigned, the simple observation of the spectra enables one to distinguish cultured from wild fish. This distinction is possible due to the presence in the former of high proportions of diunsaturated acyl groups, mainly linoleic. Furthermore, new approaches for quantitative characterization of sea bass lipids were developed. For the same season wild sea bass lipids contain not only higher molar percentages of omega-3 and of docosahexaenoic (DHA), but also higher concentrations of phosphatidylcholine and of cholesterol than farmed ones. However, in general, the absolute content of DHA and of eicosapentaenoic plus arachidonic (EPA+ARA) acyl groups as well as of phosphatidylcholine and cholesterol, were reasonably higher in farmed than in wild sea bass fillets, due to the higher total lipid content of the former. The presence of omega-1 acyl groups in all farmed samples and in some of the wild specimens was shown. As far as we know, this is the first time that omega-1 acyl groups have been identified and quantified in fish lipids by 1H NMR. [Copyright &y& Elsevier]

Abstract: Rhizoma coptidis, a broadly used traditional Chinese medicine, derives from the dried rhizomes of Coptis chinensis Franch, Coptis deltoidea C.Y. Cheng et Hsiao and Coptis teeta Wall. Quantitative determination of protoberberine alkaloids in R. coptidis is critical for controlling its quality. In this study, a rapid, simple and accurate quantitative 1H NMR (qNMR) method was developed for simultaneous determination of berberine, jatrorrhizine, epiberberine, coptisine, palmatine and columbamine in R. coptidis from the three species. Method validation was performed in terms of selectivity, precision, repeatability, stability, accuracy, robustness and linearity. The average recoveries obtained were in the range of 96.9–102.4% for all the six alkaloids. In addition, the qNMR data were analyzed with analysis of variance (ANOVA), hierarchical clustering analysis (HCA) and principal component analysis (PCA), and the results showed that the contents of the active alkaloids have significant difference among the three species. Compared with the conventional HPLC approach, the proposed qNMR method was demonstrated to be a powerful tool for quantifying the six alkaloids due to its unique advantages of high robustness, rapid analysis time and no need of standard compounds for calibration curves preparation. These findings indicate that this method has potential as a reliable method for quality evaluation of herb medicines, especially for protoberberine alkaloid-containing ones. [Copyright &y& Elsevier]

Recent trends suggest that cocaine smugglers have become more and more inventive to avoid seizures of large amounts of cocaine transported between countries. We report a case of a mail parcel containing a dance pad which was seized at the Customs Department of Brussels Airport, Belgium. After investigation, the inside of the dance pad was found to contain a thick polymer, which tested positive for cocaine. Analysis was performed using a routine colorimetric swipe test, gas chromatography coupled with mass spectrometry and nuclear magnetic resonance spectroscopy. The polymer was identified as polyvinyl alcohol (PVA) and contained 18% cocaine, corresponding to a street value of € 20,000. Laboratory experiments showed that cocaine could be easily extracted from the PVA matrix. This case report reveals a new smuggling technique for the transportation of large amounts of cocaine from one country to another. [ABSTRACT FROM AUTHOR]

The article presents a study on plasma proton nuclear magnetic resonance spectroscopy as a way to monitor metabolism after the administration of albumin in acute lung injury (ALI) patients. The researchers treated mechanically ventilated hypoproteinemic patients with continuous infusion furosemide. They found that metabolomic profiling may allow more focused trials in ALI patients with the help of a better assessment of therapeutic effects.

Abstract: Thirty four sour cherry cultivars were investigated for their total phenolic content, total anthocyanin content, total antioxidant capacity and cancer cell proliferation inhibition activity. Birgitte×Böttermö and Fanal, which contained the highest total phenolics (754 ± 13.4 and 596 ± 5.7 mg gallic acid equivalent/100 g, respectively), displayed the strongest total antioxidant capacity (63 ± 7.5 and 52 ± 6.9 μmol trolox equivalent/g, respectively) and cancer cell proliferation inhibition activity (63 ± 1.7 and 70 ± 1.6%, respectively). Surefire and Favorit were the cultivars with lowest total phenolic content (111 ± 2.2 and 74 ± 2.5 mg gallic acid equivalent/100 g, respectively) and total anthocyanin content (40 ± 1.1 and 21 ± 0.5 malvin equivalent/g, respectively), total antioxidant capacity (12 ± 2.3 and 9 ± 3.1 μmol trolox equivalent/g, respectively) and cancer cell inhibition activity (7 ± 3.5 and 2 ± 0.2%, respectively). Multivariate data analysis on proton nuclear magnetic resonance (1H-NMR) data showed discrimination of the cultivars according to their bioactivity. The present study suggests that combination of 1H-NMR and multivariate statistical analysis can be used to predict and discriminate total phenolic content, total anthocyanin content, total antioxidant capacity and cancer cell proliferation inhibition activity of sour cherry cultivars. [Copyright &y& Elsevier]

Abstract: Nanostructured lipid carriers (NLCs), made from mixtures of solid and liquid lipids, were postulated to have superior properties over solid lipid nanoparticles (SLNs). Nonetheless, the architecture of their inner cores remains elusive. The objective of this study was to elucidate the mode by which tocotrienol-rich fraction (TRF) is entrapped within NLCs and the impact of TRF interaction with solid lipids on the long-term stability of the nanoparticles. The mode of TRF localization was postulated from TEM image analysis and 1H NMR signals’ amplitude. The size, polydispersity, and fusion enthalpy were found to decrease with an increase in TRF loading, which implied a distortion in the crystallinity of the nanoparticles and the preferential entrapment of TRF within the cores of the NLCs. Nonetheless, 1H NMR spectra of TRF-NLCs broadened as TRF load decreased from 100 to 10%, which was attributed to partial TRF mobility on the surface of the nanoparticles. This was confirmed by TEM images of NLCs at 50% TRF loads. These data led to the conclusion that NLCs have limited capacity to accommodate TRF with the excess being expelled to the surface of the nanoparticles. Such arrangement may have implication on future utility of the NLCs as drug delivery vehicles. [Copyright &y& Elsevier]

Abstract: Metabonomic profiling using proton nuclear magnetic resonance (1H NMR) spectroscopy and multivariate data analysis of human serum samples was used to characterize metabolic profiles in renal cell carcinoma (RCC). We found distinct, easily detectable differences between (a) RCC patients and healthy humans, (b) RCC patients with metastases and without metastases, and (c) RCC patients before and after nephrectomy. Compared to healthy human serum, RCC serum had higher levels of lipid (mainly very low-density lipoproteins), isoleucine, leucine, lactate, alanine, N-acetylglycoproteins, pyruvate, glycerol, and unsaturated lipid, together with lower levels of acetoacetate, glutamine, phosphatidylcholine/choline, trimethylamine-N-oxide, and glucose. This pattern was somewhat reversed after nephrectomy. Altered metabolite concentrations are most likely the result of the cells switching to glycolysis to maintain energy homeostasis following the loss of ATP caused by impaired TCA cycle in RCC. Serum NMR spectra combined with principal component analysis techniques offer an efficient, convenient way of depicting tumour biochemistry and stratifying tumours under different pathophysiological conditions. It may be able to assist early diagnosis and postoperative surveillance of human malignant diseases using single blood samples. [Copyright &y& Elsevier]

The earthworm Eisenia fetida is frequently used in ecotoxicological studies; however, it has not yet been investigated using proton nuclear magnetic resonance (¹H NMR) metabolic profiling methods. The present study investigates the impact of depuration time, sample homogenization, and different extraction solvents on the quality and reproducibility of the ¹H NMR spectra of E. fetida with the goal of determining whether this species is suitable for future metabonomic studies. A depuration time of 96 h, followed by intact lyophilization before homogenization and extraction into a deuterium oxide (D2O)-based phosphate buffer, was found to produce extracts with excellent ¹H NMR reproducibility. The D2O buffer extracted the largest quantity of the widest variety of earthworm metabolites, which is consistent with the results from other studies using different earthworm species. Nuclear magnetic resonance assignments of the major metabolites in the D2O-based buffer also were performed and found to be similar to those for other earthworm species, such as Eisenia veneta, but also to have characteristic attributes in E. fetida. The major metabolites identified include amino acids (alanine, arginine, glutamic acid, glutamine, glycine, leucine, lysine, phenylalanine, serine, tyrosine, and valine), two sugars (glucose and maltose), the sugar alcohol mannitol, and the polyalcohol inositol. Two other earthworm species (Lumbricus rubellus and Lumbricus terrestris) also were examined using protocols developed for E. fetida, and of the three species, the ¹H NMR spectra of E. fetida had the least variation, indicating this species is well-suited for future metabolomicbased ecotoxicity studies. [ABSTRACT FROM AUTHOR]

Prior studies have proven that proton Nuclear Magnetic Resonance technique can be used to follow up ozone reaction with unsaturated fatty acids. In this paper, ozonation of sunflower oil at a different applied ozone dosage was carried out and peroxide index and aldehydes contents were determined. The reaction products were identified using Proton Nuclear Magnetic Resonance Spectroscopy (¹H NMR). The principal signal intensities values were used for following the reaction course between ozone and sunflower oil. The reaction was following up to peroxide index values of 1 202 mmol-equiv/kg . The intensities of olefinic proton signals decreased with the gradual increase in ozone concentration but without disappearing completely. The Criegee ozonides obtained at 107.1 mg/g of ozone doses were approximately 7.4 folds higher than that at the beginning of reaction. The aldehyde protons were observed as a weak intensity signal in all the spectra. The signals belonging to olefinic protons from hydroperoxides appeared weak with the increase in ozone doses. Signals from other oxygenized groups were assigned. It was concluded that the higher applied ozone doses the higher the ozonation reaction advance corresponding with a higher oxygenized compounds formation. [ABSTRACT FROM AUTHOR]

Abstract: A metabonomic approach to nutrition research may provide an insight into in vivo mechanisms of action following nutritional intervention. This approach was applied to investigate changes in the 1H NMR spectral profile of urine collected from controlled dietary intervention studies conducted in premenopausal women before and following soy or miso consumption. The aim of the study was to identify the biochemical effects of a diet rich in soy isoflavones, phytochemicals which are receiving significant attention because of their potential importance to human health and wide bioactivity in vitro. By applying various chemometric techniques to the data the biochemical effects of conjugated and unconjugated isoflavones were determined. The biochemical changes observed suggest that soy isoflavone ingestion had significant effects on several metabolic pathways associated with osmolyte fluctuation and energy metabolism. These biochemical changes were more significant following ingestion of the unconjugated soy isoflavone (miso) diet suggesting that the chemical composition of the isoflavones present in soy-based foods may have an effect on their biological efficacy in vivo. This study describes a novel application for 1H NMR analysis by determining subtle differences in biochemical profiles following dietary intervention and providing further insight into the mechanisms of action of phytochemicals in vivo. [Copyright &y& Elsevier]