High Performance Liquid Chromatography Coupled To Diode Array Detection Research Articles

Fast simultaneous electrochemical detection of Bisphenol-A and Bisphenol-S in urban wastewater using a graphene oxide-iron nanoparticles hybrid sensor

In this work, a novel and sensitive electrochemical sensor was developed for the simultaneous determination of low concentration levels of Bisphenol-A (BPA) and Bisphenol-S (BPS) in a secondary effluent from a wastewater treatment plant and surface water. The sensor design involved the utilization of a glassy carbon electrode that was modified with hybrid iron nanoparticles and a nanostructure of graphene oxide. The synthesized material displayed a stable heterostructure, facilitating efficient electronic transfer and exhibiting impressive electrocatalytic capacity. Furthermore, the sensor successfully detected anodic signals of BPA and BPS with a peak separation of 0.28 V, confirming its excellent performance. For method optimization, a chemometric tool based on a Central Composite Face (CCF) design response surface was employed. The optimized conditions yielded an analytical curve with a linear range of 15.0 to 120.0 µmol L−1 for BPA, represented by the equation Iap (µA)= -0.088 + 0.044 (µA L µmol−1) [cBPA], and 20.0 to 70.0 µmol L−1 for BPS, represented by the equation Iap (µA)= -0.367 + 0.025 (µA L µmol−1) [cBPS]. The detection and quantification limits for BPA were established at 12.05 and 36.51 µmol L−1, respectively. Similarly, for BPS, the corresponding values were determined to be 11.63 and 35.24 µmol L−1. The electrochemical method developed was validated by comparing it with the high-performance liquid chromatography coupled to diode array detector (HPLC-DAD) technique. Notably, the electrochemical method demonstrated to be successful in the simultaneous detection and quantification of BPA and BPS in a secondary effluent and surface water.

Chemometric tools associated to chromatographic data to assess the quality and authenticity whiskeys

Whisky is a distilled beverage consumed all over the world and is often adulterated to obtain commercial advantages. Trace analysis by chromatographic methods is essential for the quality control in the production of whisky. These methods associated with chemometrics provide powerful tools for assessing authenticity and can be used to meet the criteria for differentiating whiskeys. This study proposes a new methodology that combines chromatographic data with chemometric tools to differentiate original and counterfeit whiskeys. Thus, counterfeit (14) and original whiskeys (16) were analyzed by two chromatographic methods. The first method involved the analysis of alcohols and esters using solid phase microextraction (SPME) - headspace (HS) - gas chromatography coupled to barrier discharge ionization detector (BID), HS-SPME-GC-BID. The second method involved the analysis of carbonyl compounds, derivatized with 2,4-dinitrophenylhydrazine (2,4-DNPH), using high performance liquid chromatography coupled to diode array detector (HPLC-DAD). Data analysis was carried out by the chemometric tools, such as principal component analysis (PCA), hierarchical cluster analysis (HCA) and partial least-squares discriminant analysis (PLS-DA). The merit figures for the 2,4-DNPH-HPLC-DAD method were studied, such as selectivity, linearity, recovery and precision. The homoscedasticity evaluation of the variances revealed heteroscedastic data and the quantitative analysis was performed using the weighted linear squares method (WLS). Correlation coefficients varied from 0.990 to 0.999. The significance assessment showed that the linear and angular coefficients were significant. Recovery and precision values of the method, respectively, ranged from 80.84 to 107.21 %, and 0.99 to 3.94 %, for the aldehydes, except for acrolein at one of the concentration levels. The HCA distinguished most of the whisky samples, PCA and PLS-DA distinguished the two classes completely. However, PLS-DA showed a greater predictive capacity than the PCA, as well as high sensitivity, specificity and precision. The validation of the 2,4-DNPH-HPLC-DAD was satisfactory, and chemometric tools allowed the differentiation between the original and counterfeit whiskeys.

Residual Lignocellulosic Biomass in the Production of HMF

5-Hydroxymethylfurfural (HMF) can be obtained from the dehydration of monosaccharides present in biomass, which helps add value to the raw material. The present work sought to study the relationship between the parameters of biomass characterization, including the content of reducing sugars, total soluble solids and the mid-infrared (MIR) and near-infrared (NIR) spectra, and the formation of HMF after synthesis. A thorough analysis was conducted in order to evaluate the residual agricultural biomass samples from sugarcane bagasse, corn stover, cassava branch, banana pseudostem and mango fruits after the drying (45 ºC maximum) and ball mill grinding pre-processing procedure. HMF synthesis was performed using 0.50 mol L-1 HCl and n-butanol as extracting solvent. The analytical quantification of HMF and furfural (co-product of synthesis) was performed using high-performance liquid chromatography coupled to diode-array detector (HPLC-DAD). The highest efficiency of the synthesis of HMF was observed for the mango fruits (55.0 kg ton-1) and sugarcane bagasse biomass (47.5 kg ton-1) samples. The application of data fusion and principal component analysis (PCA) allowed us to identify the samples with greater potential for HMF synthesis.

Using 3D printed magnetic platform as support for screen printed electrode applied for p-toluenediamine detection in biological fluid and water samples

The present work reports the development and application of a new electrochemical sensor for the determination of low concentration levels of p-toluenediamine (PTD) in biological fluids and surface water samples. The proposed sensor was developed using a 3D-printed magnetic device as platform for carbon screen printed electrode (CSPE) modified by magnetic nanoparticles functionalized with carboxylic groups and l-cysteine (MNP-CA-CYS). The results obtained from the morphological and electrochemical characterizations of the sensing platform enabled us to confirm the success of the sensor functionalization with l-cysteine and to have a better understanding of the electrochemical behavior and preconcentration of PTD on the electrode surface. PTD oxidation occurred at 0.24V on MNP-CA-CYS and the mechanism recorded an increase of 51.0% in anodic peak current. Under optimized conditions, the square wave voltammograms obtained for the electrode modified by 40.0 μL MNP-CA-CYS suspension at 1.0 mg mL−1, with accumulation time of 3 min, presented an analytical curve with linear range of 8.00 × 10−7 to 8.00 × 10−5 mol L−1, represented by the equation Iap = (0.383 ± 0.011)[PTD] - (8.112 ± 0.07) × 10−8 (R2 = 0.9994), and detection and quantification limits of 8.53 × 10−8 and 2.56 × 10−7 mol L−1, respectively. Finally, the proposed method was validated through comparison with high performance liquid chromatography coupled to diode array detector (HPLC-DAD) technique and was successfully applied for PTD determination in samples of surface water, tap water, fetal bovine serum and artificial urine.

Major lipophilic pigments in Atlantic seaweeds as valuable food ingredients: Analysis and assessment of quantification methods

Current trends towards the use of ingredients from natural origin in food, cosmetic and pharmaceutical industry, place macroalgae as a good reservoir of novel compounds. Among them, lipophilic major pigments such as chlorophylls and fucoxanthin, are of great interest because of their multiple applications as bioactive compounds and dyes. In this work, a mid-polarity medium was used to extract pigments from twenty-four species from North coast of Spain, including brown (Phaeophyceae) and red macroalgae (Rhodophyta). The fucoxanthin and chlorophyll a content was assessed by means of two different methods, spectrophotometric and high-performance liquid chromatography coupled to diode array detection (HPLC-DAD). The effect of dried processing on the pigment content of selected species was also evaluated. A linear relationship between the extractability of fucoxanthin and chlorophyll a was observed, being the highest content recorded among members belonging to the order Fucales and Undaria pinnatifida. This work provides good insights about the content on pigments in Spanish North Atlantic macroalgae with future commercial value in different industrial fields, as well as a critical overview of the suitability of the quantification methods and challenges related to their effect in results evaluation.

Cannabinoid receptor activation potential of the next generation, generic ban evading OXIZID synthetic cannabinoid receptor agonists

In recent years, several nations have implemented various measures to control the surge of new synthetic cannabinoid receptor agonists (SCRAs) entering the recreational drug market. In July 2021, China put into effect a new generic legislation, banning SCRAs containing one of seven general core scaffolds. However, this has driven manufacturers towards the synthesis of SCRAs with alternative core structures, exemplified by the recent emergence of "OXIZID SCRAs." Here, using in vitro β-arrestin2 recruitment assays, we report on the CB1 and CB2 potency and efficacy of five members of this new class of SCRAs: BZO-HEXOXIZID, BZO-POXIZID, 5-fluoro BZO-POXIZID, BZO-4en-POXIZID, and BZO-CHMOXIZID. All compounds behaved as full agonists at CB1 and partial agonists at CB2 . Potencies ranged from 84.6 to 721 nM at CB1 and 2.21 to 25.9nM at CB2 . Shortening the n-hexyl tail to a pentyl tail enhanced activity at both receptors. Fluorination of this pentyl analog did not yield a higher receptor activation potential, whereas an unsaturated tail resulted in decreased potency and efficacy at CB1 . The cyclohexyl methyl analog BZO-CHMOXIZID was the most potent compound at both receptors, with EC50 values of 84.6 and 2.21 nM at CB1 and CB2 , respectively. Evaluation of the activity of a seized powder containing BZO-4en-POXIZID suggested a high purity, in line with high-performance liquid chromatography coupled to diode-array detection (HPLC-DAD), gas chromatography coupled to mass spectrometry (GC-MS), liquid chromatography coupled to time-of-flight mass spectrometry (LC-QTOF-MS), and Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) analysis. Furthermore, all tested compounds showed a preference for CB2 , except for BZO-POXIZID. Overall, these findings inform public health officials, law enforcement agencies, and clinicians on these newly emerging SCRAs.

A new cannabinoid receptor 1 selective agonist evading the 2021 "China ban": ADB-FUBIATA.

Following the class-wide ban of synthetic cannabinoid receptor agonists (SCRAs) in China, SCRAs carrying new core and linker structures, aimed at circumventing the recent Chinese generic legislation, have appeared on the recreational drug market. A very recent example is (S)-2-(2-(1-(4-fluorobenzyl)-1H-indol-3-yl)acetamido)-3,3-dimethylbutanamide (ADB-FUBIATA), which is structurally closely related to the potent SCRA ADB-FUBICA, but carries an additional methylene in the linker region of the molecule. ADB-FUBIATA has recently been identified in seized materials in China, Russia, the United States, and also Belgium; however, its pharmacological characteristics were unknown. The aim of this study was to evaluate the intrinsic cannabinoid receptor (hCB1 and hCB2 ) activation potential of this previously unknown substance via two distinct yet similar in vitro β-arrestin2 recruitment assays, based on the NanoLuc Binary Technology®. At CB1 , a potency of 635 nM (EC50 ) was found, with an efficacy (Emax ) of 141% relative to the reference compound CP55,940. On the other hand, ADB-FUBIATA had almost no activity at CB2 , indicative of a clear CB1 selectivity. Interestingly, this activation pattern differs markedly from that observed for ADB-FUBICA, which was previously found to be potent and efficacious at both cannabinoid receptors. Additionally, the bioassays were applied to a seized powder containing ADB-FUBIATA, as analytically confirmed by high-performance liquid chromatography coupled to diode-array detection (HLPC-DAD), gas chromatography coupled to mass spectrometry (GC-MS), liquid chromatography couple to time-of-flight mass spectrometry (LC-QTOF-MS), Fourier transform infrared spectroscopy (FTIR), and nuclear magnetic resonance (NMR). The EC50 and Emax values obtained for this powder were very similar to those of the ADB-FUBIATA analytical standard, suggesting a high purity of the powder, although analytical techniques did reveal that the sample was not entirely pure.

Determination of biogenic amines formation by autochthonous lactic acid bacteria from ‘Refošk’ grapes using different analytical methods

Different analytical methods were tested and optimized for the determination of four biogenic amines (BA) histamine, putrescine, cadaverine and tyramine produced by grape-associated lactic acid bacteria (LAB). Autochthonous LAB were isolated from ‘Refošk’ grapes belonging to Slovenian-Italian Karst region as they represent a potential pool of beneficial LAB starter bacteria for improving the typicality and quality of wine. Six isolated strains were screened by multiplex PCR, of which four strains were positive for BA-forming genes (MKBT-49, MKBT-282, MKBT-568, MKBT-570). The production of BA was evaluated by thin-layer chromatography (TLC), high-performance liquid chromatography coupled to diode array detection (HPLC-DAD) and enzymatic method. The HPLC-DAD results showed that strain MKBT-49 (tyrdc+) had high tyramine production (386.6 ± 0.14 mg/L), which was confirmed by TLC. The ability to produce putrescine was confirmed in strain MKBT-282 by PCR, HPLC-DAD (16.4 ± 1.72 mg/L), and TLC. Histamine-producing ability was detected in strain MKBT-570, with a concentration below the limit of detection of the HPLC-DAD (<0.2 mg/L), while the other two methods were not sensitive enough for confirmation. This study shows that the production of BA can detected in native LAB and that relatively simple method such as TLC can be used effectively for the initial screening.

Synthesis, Chemical Characterization, and μ-Opioid Receptor Activity Assessment of the Emerging Group of "Nitazene" 2-Benzylbenzimidazole Synthetic Opioids.

Several 2-benzylbenzimidazole opioids (also referred to as "nitazenes") recently emerged on the illicit market. The most frequently encountered member, isotonitazene, has been identified in multiple fatalities since its appearance in 2019. Although recent scheduling efforts targeted isotonitazene, many other analogues remain unregulated. Being structurally unrelated to fentanyl, little is known about the harm potential of these compounds. In this study, ten nitazenes and four metabolites were synthesized, analytically characterized via four different techniques, and pharmacologically evaluated using two cell-based β-arrestin2/mini-Gi recruitment assays monitoring μ-opioid receptor (MOR) activation. On the basis of absorption spectra and retention times, high-performance liquid chromatography coupled to diode-array detection (HPLC-DAD) allowed differentiation between most analogues. Time-of-flight mass spectrometry (LC-QTOF-MS) identified a fragment with m/z 100.11 for 12/14 compounds, which could serve as a basis for MS-based nitazene screening. MOR activity determination confirmed that nitazenes are generally highly active, with potencies and efficacies of several analogues exceeding that of fentanyl. Particularly relevant is the unexpected very high potency of the N-desethylisotonitazene metabolite, rivaling the potency of etonitazene and exceeding that of isotonitazene itself. Supported by its identification in fatalities, this likely has in vivo consequences. These results improve our understanding of this emerging group of opioids by laying out an analytical framework for their detection, as well as providing important new insights into their MOR activation potential.

Determination of veterinary antibiotics in cow milk using rotating-disk sorptive extraction and liquid chromatography

A novel application of rotating disk sorptive extraction (RDSE), using a styrene-divinylbenzene (S-DVB) sorbent for the extraction of antibiotic residues in milk was developed. The analytes studied were oxytetracycline and its 4-epimer, enrofloxacin, ciprofloxacin, sulfadoxine and trimethoprim. After RDSE, the analytes were determined by performing both high-performance liquid chromatography coupled to diode array detection (HPLC-DAD) and ultrahigh-performance liquid chromatography coupled to ultraspray-electrospray-time of flight-mass spectrometry (UPLC-TOF/MS).By using HPLC-DAD, the absolute recoveries were between 85.5% and 106.4% with relative standard deviations between 3.7% and 9.9%. The obtained limits of quantification (LOQs) were lower than the respective maximum residue levels (MRLs) reported for each analyte, demonstrating that the methodology was applicable for residue depletion studies. UPLC-TOF/MS showed absolute recoveries from 88.5% to 114.1%, with RSDs between 4.3% and 15.4%. The LOQs obtained using UPLC-TOF/MS were also lower than the MRLs for each respective analyte.Compared with other analytical methods previously reported for some of the analytes, the present method is simpler and less expensive and utilizes green chemistry, all while providing comparable figures of merit.

Hydroethanolic Extract of Lampaya Medicinalis Phil. (Verbenaceae) Decreases Proinflammatory Marker Expression in Palmitic Acid-exposed Macrophages.

Obesity is a major health problem associated with increased comorbidities, which are partially triggered by inflammation. Proinflammatory macrophage infiltration in adipose tissue of individuals with obesity increases chronic inflammation. Obesity is associated with elevated plasma levels of saturated fatty acids, such as palmitic acid (PA), which promotes inflammation in vivo and in vitro. Infusions of Lampaya medicinalis Phil. (Verbenaceae) are used in the folk medicine of Northern Chile to counteract inflammation of rheumatic diseases. Hydroethanolic extract of lampaya (HEL) contains spectrophotometrically defined compounds that may contribute to the observed effect on inflammation. We evaluated the phytochemical composition of HEL by high-performance liquid chromatography coupled to diode array detection (HPLC-DAD) and liquid chromatography-electrospray ionization- tandem mass spectrometry (LC-ESI-MS/MS). We assessed whether the exposure to HEL affects PA-induced expression of proinflammatory factors in THP-1 macrophages. HPLC-DAD and LC-ESI-MS/MS analyses showed the presence of considerable amounts of flavonoids in HEL. The PA-induced phosphorylation of the inflammatory pathway mediators IKK and NF-κB, as well as the elevated expression and secretion of proinflammatory cytokines (IL-6, TNF-α), were reduced in cells pre-exposed to HEL. These findings give new insights about the effect of HEL reducing IKK/NF-κB proinflammatory pathway, likely explained by the number of flavonoids contained in the extract. More studies would be needed to define the possible role of Lampaya as a preventive approach in subjects with obesity whose circulating PA might contribute to chronic inflammation.

Changes in phenolic compounds and antioxidant capacity of Andean raspberries in response to Peronospora sparsa

In Colombia, the Andean raspberry (Rubus glaucus Benth) is of large economic significance because of its use in industry and widespread consumption as a fresh fruit. However, this crop is highly susceptible to disease by Peronospora sparsa, a fungus that causes between 50 % and 70 % production loss. Plants respond to pathogen-induced damage by increasing the production of specific secondary metabolites, such as phenolic compounds, which have broad industrial applications. This work estimated the antioxidant capacity and phenolic content of healthy and Peronospora sparsa-infected Andean raspberry fruits. Antioxidant capacity was analyzed by DPPH and FRAP methods, while phenolic compounds were analyzed by high performance liquid chromatography coupled to diode array detection (HPLC-DAD). According to the DPPH method, antioxidant capacity increased from 45.9 ± 1.61 µmol TE g−1 fresh sample in healthy fruits to 67.02 ± 0.58 µmol TE g−1 fresh sample in affected fruits. The FRAP method revealed an antioxidant response difference from 5.19 ± 0.8 mmol TE 100 g−1 fresh sample in healthy fruits vs. 10.97 ± 0.27 mmol TE 100 g−1 fresh sample in affected fruits. The phenolic compound content was observed in a range of 4.14 ± 1.16 to 72.03 ± 26.68 mg GAE L−1 for healthy fruits and from 4.48 ± 1.76 to 221.89 ± 1.18 mg GAE L−1 for affected fruits. Phenolic acids were the main phenols detected, encompassing derivatives of gallic acid, chlorogenic acid, ferulic acid, ellagic acid, and p-coumaric acid. This work confirmed that the Peronospora sparsa-infected berries contained relatively more antioxidants and phenolic acid compounds than their healthy counterparts, and that this difference was likely due to a defense mechanism to cope with pathogen-induced damage.

Design and Characterization of Bioactive Bilayer Films: Release Kinetics of Isopropyl Palmitate

Active packaging incorporating antioxidants and antimicrobials is creating a niche in the market and becoming increasingly important. The main goal of this work was the design of bioactive bilayer films (zein/pullulan) incorporating licorice essential oil. The bilayer films were fully characterized in terms of their chemical, physical, barrier, antioxidant, and antimicrobial properties. Furthermore, the release kinetics of isopropyl palmitate, the major compound of the licorice essential oil, was evaluated by HPLC-DAD (high-performance liquid chromatography coupled to diode-array detector). Scanning Electron Microscopy (SEM) micrographs of cross-sections of the bilayer films clearly show the two layers of the films. Besides presenting the capacity to scavenge free radicals and to inhibit the lipid peroxidation, the developed bilayer films were also able to inhibit the growth of known foodborne pathogens (Enterococcus faecalis and Listeria monocytogenes). The release kinetics profile of isopropyl palmitate from bilayer films incorporating licorice essential oil demonstrated that in 50% ethanol at room temperature, the release was more effective, suggesting that the bilayer films will be more efficient if applied to package semi-fatty food.

Julbernardia paniculata and Pterocarpus angolensis: From Ethnobotanical Surveys to Phytochemical Characterization and Bioactivities Evaluation.

Julbernardia paniculata and Pterocarpus angolensis are two plant species with important application in African traditional medicine, particularly in Angola, in the treatment of several diseases. However, scientific studies concerning these species are scarce. The goal of this work was to know better which medicinal approaches are used by the Huíla population in Angola by means of ethnobotanical surveys. Furthermore, extracts of both plants were phytochemically characterized. Antioxidant, anti-inflammatory, wound-healing activities, and potential cytotoxicity were also studied. With this study it was possible to verify that 67% of the individuals that use medicinal plants are women, and their main therapeutic uses are the treatment of problems of the digestive system and skin disorders. Barks of J. paniculata and leaves of P. angolensis are the most often used plant parts. Through high-performance liquid chromatography coupled to diode-array detector (HPLC-DAD) and GC-MS it was possible to characterize the chemical composition of the two species, which are rich in phenolic compounds, terpenes, terpenoids, sesquiterpenoids and fatty acids. Both plants showed to possess antioxidant, anti-inflammatory proprieties, and wound-healing activity. To the best of our knowledge, this is the most comprehensive study of these two species and the first ethnobotanical and ethnopharmacological study of medicinal plants from this region of Angola.

Proteolytic regulation of the extent of dietary proteins with skin grape proanthocyanidin and anthocyanidin's interactions

SummaryDuring technological processing, proanthocyanidins and anthocyanidins could be partly lost due to the complexation phenomena, affecting food and beverage nutritional properties, organoleptic properties and health‐promoting potentials. A common issue is encountered when processing food and beverage which is binding of phenolics to dietary proteins. The present investigation aims at evaluating the proteolysis contribution, using pure protease (Pepsin, 3000 units g−1), to protein–anthocyanidin and protein–proanthocyanidin interactions. Bovine serum albumin (BSA), ovalbumin (OVA) and casein (CAS) dietary protein models were used. High‐performance liquid chromatography coupled to diode array detector (HPLC‐DAD) and size exclusion chromatography analyses proved that pepsin treatment significantly (P &gt; 0.05) decreased the ratio of flavonoids’ interaction with tested proteins . The proteolysis reduced anthocyanidin interactions with CAS, OVA and BSA by 64.88%, 57.37% and 42.87% respectively. Similarly, proanthocyanidins interaction with CAS, OVA and BSA were reduced by 34.23%, 13.74% and 2.39% respectively. This study provides the basis to develop innovative technologies to limit protein–flavonoid complexation during food and beverage processing.

Ethanolic extract of the aerial parts of Passiflora cincinnata Mast. (Passifloraceae) reduces nociceptive and inflammatory events in mice

BackgroundPassiflora cincinnata Mast. is described as a native species from the Caatinga biome, and used by traditional medicine for several pharmacological purposes, such as inflammatory disorders. However, studies that prove its biological activities are scarce. Hypothesis/purposeThis paper aims to evaluate the antinociceptive and anti-inflammatory activities of the aerial parts of Passiflora cincinnata (Pc-EtOH) in mice. MethodsThe chemical composition of Pc-EtOH was assessed by high-performance liquid chromatography coupled to diode array detector (HPLC-DAD). The antinociceptive profile of the extract (given orally: 100, 200 and 400 mg/kg) was established using the in vivo chemical models (acetic acid-induced abdominal constriction and formalin-induced paw licking test) and thermal (hot plate test) of nociception. The role of opioid, potassium channels, TRPV-1, muscarinic, serotoninergic (5-HT3) receptors and the participation of the nitric oxide pathway also was determined. The rota-rod test was used to verify the possible interference of the extract treatment in motor performance. Paw edema induced by carrageenan or histamine, and leukocyte migration, determination of total protein and nitric oxide to the peritoneal cavity were used for anti-inflammatory profile. ResultsThe presence of flavonoids in the extract was confirmed using HPLC-DAD. At all doses tested the Pc-EtOH significantly reduced the number of writhing and decreased the paw licking time in both phases of the formalin test (p < 0.05). In the hot plate test, the extract increased the reaction time, reducing painful behavior. The antinociceptive mechanism probably involves central and peripheral pathways, involving the pathway of opioid and muscarinic receptors with influence of potassium channels and the nitric oxide pathway. However, the motor coordination test indicated that in the time of 120 min the extract decreases the stay time of the animal in the rota-rod. Pc-EtOH inhibited significantly (p < 0.05) the increase of the edema volume after administration of carrageenan and histamine. In the peritonitis test, acute pre-treatment with Pc-EtOH inhibited leukocyte migration, with a reduction in the number of neutrophils and concentration of total proteins and nitric oxide. ConclusionThe present study suggests that Pc-EtOH possesses peripheral and central antinociceptive action, and showed potential in inhibition of release of mediators of the inflammatory process.

An analytical strategy based on Fourier transform infrared spectroscopy, principal component analysis and linear discriminant analysis to suggest the botanical origin of resins from Bursera. Application to archaeological Aztec Samples

Bursera species are the source of oleoresins that have been used by pre-Columbian American cultures as adhesives, raw materials for molding figurines, ritual offerings, among other uses. Spread along different museum collections all over the world, pre-Columbian artefacts contain these resins. The preservation and understanding of the technology of fabrication of these pieces constitute a major concern for conservators, historians and archaeologists. Few studies have so far dealt with the chemical composition and the botanical origin of Mexican copal, owing maybe to the difficulty on the procuration of resins from known botanical origin. In this work, fresh resins from six Mexican Bursera species, namely B. bipinnata, B. excelsa, B. grandifolia, B. laxiflora, B. penicillata and B. stenophylla, were analyzed by Fourier-transformed infrared spectroscopy (FTIR). Main spectral band positions were selected for chemometric analysis using principal component analysis (PCA), based on the loading plot of chemometric analysis. Sample distribution patterns were investigated with PCA. Score plots revealed a sample agglomeration with good differentiation in 5 out of the 6 species. This method was validated by linear discriminant analysis (LDA) with a 95.2% of global positive recognition for certified origin species. To compare the efficiency of this approach, high performance liquid chromatography coupled to diode array detection (HPLC-DAD) and FTIR results were coupled to PCA and LDA, for the same set of samples. “FTIR showed 94.4% of samples correctly assigned on the confusion matrix and 91% on the cross validation one. HPLC-LDA showed 100% of correct assignment in the confusion matrix and 95% on the cross validation one. These results are encouraging, as FTIR is much faster and less expensive than chromatographic techniques and it could more readily be available in conservation laboratories. Finally, an application to the identification of the botanical origin of four archaeological Aztec copal samples was performed and the model suggested an origin on B. bipinnata/B. stenophylla for these archaeological samples.

Evaluation of phenolic composition and antioxidant activity changes in olive flowers during development using HPLC/DAD and LC-MS/MS.

Olive fruit and leaves have been extensively studied for their chemical compositions and biological activities. However, less attention has been given to its flowers. The present research was achieved on Tunisian olive flowers. It aimed at studying the effects of flower development on phenolic compounds and antioxidant activity. The extracts were analyzed using high performance liquid chromatography coupled to diode array detection (HPLC/DAD) and coupled to mass spectrometry (LC-MS/MS). The HPLC/DAD analysis indicated that oleuropein aglycon (from 1.158 to 3.746g/kg), followed by hydroxytyrosol (from 0.168 to 1.581g/kg) and oleoside (from 0.143 to 1.325g/kg) were the predominant phenolics in olive flowers extracts during development stages. Twenty compounds have been identified, revealing the complex profile of olive flowers, composed, in order of abundance, by secoiridoids, phenolic alcohols, lignans, flavonoids and phenolic acids. Total phenolic contents increased from 2.455 to 8.541g/kg Gallic acid equivalent per kg of fresh flowers during all steps of the flower development. A correlation between antioxidant activity and total phenolic contents was determined.

DETERMINATION OF TRICLABENDAZOLE IN CATTLE PLASMA AS ITS SULPHOXIDE AND SULPHONE METABOLITES BY ROTATING DISK SORPTIVE EXTRACTION COMBINED WITH HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY AND ITS APPLICATION TO PHARMACOKINETIC STUDIES

In this study, a new method for determination of triclabendazole (TCB) as its main metabolites, triclabendazole sulfoxide (TCB-SO) and triclabendazole sulfone (TCB-SO2) in animal plasma was developed. TCB is widely used as antiparasitic in the veterinary industry. Rotating disk sorptive extraction (RDSE) was the selected sample preparation technique for extraction/clean up of the compounds from the samples followed by high performance liquid chromatography coupled to diode array detection (HPLC-DAD) for quantification. Optimization of physicochemical variables was performed using a multivariate experimental design. Following the recommendations given in the Veterinary International Conference on Harmonization guides (VICH GL02 and VICH GL49), the validation of the method was performed, given rise to improved analytical features compared with those provided by other methods based on solid phase extraction (SPE). Linearity (r > 0.99) was achieved for both compounds when calibration was performed not only in standard solutions but also in animal spiked plasma. Selectivity, defined as the response ratio between blank and analyte at the limit of quantification, was 11.8% and 3.4% for TCB-SO and TCB-SO2, respectively. Accuracy and precision, expressed in percentage, were always lower than -16.7% and 8.1%, respectively. Eco-efficiency was quantitatively assessed indicating that the method is an excellent green method. The proposed analytical method was applied to the determination of the pharmacokinetic of two commercial products of TCB in cattle plasma after oral administration. The good analytical performance, eco-efficiency and economy, make the method interesting for alternative use in routine laboratories.

Strategies to Document Adulteration of Food Supplement Based on Sea Buckthorn Oil: a Case Study

In this case study, a food supplement with declared content of sea buckthorn oil was investigated since it was suspected to be adulterated by sunflower oil. Polar and non-polar fractions extracted from oil supplement were analyzed and compared with authentic sea buckthorn and sunflower oils examined in the same way. Three different analytical platforms were used in order to characterize these samples: (i) ambient mass spectrometry consisting of direct analysis in real time (DART) ion source coupled to quadrupole time-of-flight mass spectrometry (Q-TOF MS); (ii) ultra performance liquid chromatography (UHPLC) coupled to quadrupole time-of-flight mass spectrometry, and (iii) high-performance liquid chromatography coupled to diode array detector (HPLC-DAD). The fingerprints of polar and non-polar extracts, regardless they were obtained by DART-HRMS and/or UHPLC-HRMS, were almost identical with those of sunflower “reference” oil. The last of employed techniques, HPLC-DAD, provided complementary information on the occurrence of various visible light-absorbing compounds. While a rich carotenoid profile was shown in sea buckthorn oil, dominated by β-carotene, lutein, and lycopene, the color of the suspected sample was caused only by high concentration of β-carotene. In principle, these techniques proved to be suitable and complementary tools for oil authentication and allowed an oil supplement to be rapidly verified.