Ultra-high Performance Liquid Chromatography-photodiode Array Research Articles

Valorisation of fruit peel bioactive into green synthesized silver nanoparticles to modify cellulose wrapper for shelf-life extension of packaged bread

Fruit peels are rich source of bioactive compounds such as polyphenols, flavonoids, and antioxidants but are often discarded as waste due to limited pharmaceutical and nutraceutical applications. This study aimed to valorise pomegranate and citrus fruit peel into green synthesised silver nanoparticles (AgNPs) in order to modify cellulose-based wrapping material for prospective food packaging applications and propose an alternate and sustainable approach to replace polyethene based food packaging material. Four different concentrations of AgNO3 (0.5 mM, 1 mM, 2 mM, and 3 mM) were used for green synthesis of AgNPs from fruit peel bioactive, which were characterised followed by phytochemical analysis. Ultraviolet–Visible spectroscopy showed surface plasmon resonance at 420 nm, XRD analysis showed 2θ peak at 27.8°, 32.16°, 38.5°, 44.31°, 46.09°, 54.76°, 57.47°, 64.61° and 77.50° corresponding to (210), (122), (111), (200), (231), (142), (241), (220) and (311) plane of face centred cubic crystal structure of AgNPs. Fourier-transform infrared spectroscopy analysis of AgNPs green synthesised from pomegranate and kinnow peel extract showed a major peak at 3277, 1640 and 1250–1020 1/cm while a small peak at 2786 1/cm was observed in case of pomegranate peel extract which was negligible in AgNPs synthesized from kinnow peel extract. Particle sizes of AgNPs showed no statistically significant variance with p > 0.10 and thus, 2 mM was chosen for further experimentation and modification of cellulose based packaging material as it showed smallest average particle size. Zeta potential was observed to be nearly neutral with a partial negative strength due to presence of various phenolic compounds such as presence of gallic acid which was confirmed by ultrahigh performance liquid chromatography-photodiode array(UHPLC-PDA) detector. Thermal stability analysis of green synthesised AgNPs qualified the sterilisation conditions up to 100 °C. AgNPs green synthesized from both the peel extracts had higher polyphenolic content, antioxidant and radical scavenging activity as compared to peel extracts without treatment (p < 0.05). The cellulose based food grade packaging material was enrobed by green synthesised AgNPs. The characterisation of modified cellulose wrappers showed no significant difference in thickness of modified cellulose wrappers as compared with untreated cellulose wrapper (p > 0.42) while weight and grammage increased significantly in modified cellulose wrapper (p < 0.05). The colour values on CIE scale (L*, a* and b*) showed statistically significant increase in yellow and green colour (p < 0.05) for modified cellulose wrappers as compared to control wrapper. The oxygen permeability coefficient, water vapour permeability coefficient, water absorption capacity and water behaviour characteristics (water content, swelling degree and solubility) showed significant decrease (p < 0.05) for modified cellulose wrapper as compared to control wrapper. A uniform distribution and density of green synthesised AgNPs across cellulose wrapper matrix was observed through scanning electron microscopy (SEM) images with no significant aggregation, confirming successful enrobing and stable immobilisation of nanoparticles from cellulose matrix. A seven-day storage study of bread wrapped in modified and control cellulose wrappers showed delayed occurrence of microbial, yeast and mould count in bread packaged in modified cellulose wrappers and thus, resulting in shelf life extension of bread. The results are encouraging for the potential applications of modified cellulose wrappers to replace polyethene based food packaging.

Protective effects on ovalbumin-induced mouse asthma models and qualitative and quantitative analysis of multiple compounds in Gerberae Piloselloidis Herba.

Gerberae Piloselloidis Herba is widely used to treat cough and asthma in China. However, its effects on allergic asthma as related to its chemical compositions have not been fully elucidated, and there is a scarcity of methods to determine multi-component contents for quality control. In this study, protective effects of Gerberae Piloselloidis Herba on ovalbumin-induced asthma models were investigated, while qualitative and quantitative analyses of multiple constituents in Gerberae Piloselloidis Herba were conducted by using an ultrahigh-performance liquid chromatography-Q Exactive hybrid quadrupole-orbitrap high-resolution accurate mass spectrometry and an ultrahigh-performance liquid chromatography-photodiode array detection. The results showed that Gerberae Piloselloidis Herba could significantly mitigate asthma symptoms, reduce eosinophils counts in the bronchoalveolar lavage fluid, as well as decrease IgE, IL-5, and IL-13 concentration, and inflammatory cellular infiltration in lung tissues. A total of 51 compounds were tentatively identified, in which the content of 10 representative compounds was determined in 24 batches of Gerberae Piloselloidis Herba by using an ultrahigh-performance liquid chromatography method with good linearity, precision, repeatability, accuracy, and stability. This research presents a comprehensive strategy combining biological activity evaluation with chemical profiling, providing a useful and comprehensive reference for further application and quality control of Gerberae Piloselloidis Herba.

Evaluation of 30-days stability of morphine hydrochloride and clonidine at high and low concentrations in polypropylene syringes

ObjectivesClonidine is an alpha-2 adrenoreceptor agonist and is frequently combined with opioids (ie, morphine hydrochloride (HCl)) for the management of chronic pain. In palliative care, the administration of clonidine and...

UHPLC-MS Chemical Fingerprinting and Antioxidant, Antiproliferative, and Enzyme Inhibition Potential of Gaultheria pumila Berries.

Gaultheria pumila (Ericaceae) (known as Chaura or Mutilla) is a Chilean native small shrub that produces berry fruits consumed by local Mapuche people. In this study, the chemical fingerprinting and antioxidant, enzyme inhibition, and antiproliferative activities of the berries were investigated for the first time. Thirty-six metabolites were identified in the fruits by ultra-high performance liquid chromatography-photodiode array detection, hyphenated with Orbitrap mass spectrometry analysis (UHPLC-DAD-Orbitrap-MS). Metabolites, included anthocyanins, phenolic acids, flavonoids, iridoids, diterpenes, and fatty acids. Moderate inhibitory activities against acetylcholinesterase (7.7 ± 0.3 µg/mL), butyrylcholinesterase (34.5 ± 0.5 µg/mL), and tyrosinase (3.3 ± 0.2 µg/mL) enzymes were found. Moreover, selected major compounds were subjected to docking assays in light of their experimental inhibition. Results indicated that hydrogen bonding, π–π interaction, and a salt bridge interaction contributed significantly. Gaultheria pumila berries showed a total phenolic content of 189.2 ± 0.2 mg of gallic acid equivalents/g, total flavonoid content of 51.8 ± 0.1 mg quercetin equivalents/g, and total anthocyanin content of 47.3 ± 0.2 mg of cianydin-3-glucoside equivalents/g. Antioxidant activity was assessed using DPPH (92.8 ± 0.1 µg/mL), FRAP (134.1 ± 0.1 μmol Trolox equivalents/g), and ORAC (4251.6 ± 16.9 μmol Trolox equivalents/g) assays. Conversely, Gaultheria pumila showed a scarce antiproliferative potential against several solid human cancer cells. Our findings suggest that Gaultheria pumila berries have several bioactive metabolites with inhibitory effects against acetylcholinesterase, butyrylcholinesterase, and tyrosinase, and have the potential for use in food supplements.

Ceftolozane–tazobactam in an elastomeric infusion device for ambulatory care: an in vitro stability study

ObjectivesPublished in vitro stability data for ceftolozane–tazobactam supports intermittent short duration infusions. This method of delivery is not feasible for many outpatient antimicrobial therapy services that provide only one or...

Modulation of Glucosinolate Composition in Brassicaceae Seeds by Germination and Fungal Elicitation.

Glucosinolates (GSLs) are of interest for potential antimicrobial activity of their degradation products and exclusive presence in Brassicaceae. Compositional changes of aliphatic, benzenic, and indolic GSLs of Sinapis alba, Brassica napus, and B. juncea seeds by germination and fungal elicitation were studied. Rhizopus oryzae (nonpathogenic), Fusarium graminearum (nonpathogenic), and F. oxysporum (pathogenic) were employed. Thirty-one GSLs were detected by reversed-phase ultrahigh-performance liquid chromatography photodiode array with in-line electrospray ionization mass spectrometry (RP-UHPLC-PDA-ESI-MSn). Aromatic-acylated derivatives of 3-butenyl GSL, p-hydroxybenzyl GSL, and indol-3-ylmethyl GSL were for the first time tentatively annotated and confirmed to be not artifacts. For S. alba, germination, Rhizopus elicitation, and F. graminearum elicitation increased total GSL content, mainly consisting of p-hydroxybenzyl GSL, by 2–3 fold. For B. napus and B. juncea, total GSL content was unaffected by germination or elicitation. In all treatments, aliphatic GSL content was decreased (≥50%) in B. napus and remained unchanged in B. juncea. Indolic GSLs were induced in all species by germination and nonpathogenic elicitation.

Technical note: Simultaneous carotenoid and vitamin analysis of milk from total mixed ration-fed cows optimized for xanthophyll detection

Concentrations of retinol, α-tocopherol, and major carotenoids in dairy products are often determined simultaneously by liquid chromatography. These compounds have different polarity and solubility; thus, extracting them simultaneously can be difficult and inefficient. In milks with low carotenoid concentrations, the xanthophylls lutein and zeaxanthin may not be completely resolved using common extraction techniques. A simplified method was developed to optimize extraction efficiency and the limit of detection and limit of quantification (LoQ) of lutein and zeaxanthin in bovine milk without decreasing sensitivity to other vitamins or carotenoids. The developed method evaluates lutein, zeaxanthin, β-carotene, retinol, and α-tocopherol simultaneously by ultra-high performance liquid chromatography-photodiode array detection. Common saponification temperatures (40-60°C) and concentrations of KOH in water (10-50% KOH wt/vol) were evaluated. Multiple solvents were evaluated for optimal xanthophyll extraction (diethyl ether, dichloromethane, hexane, and tetrahydrofuran) following saponification. The limit of detection and LoQ were defined as 3:1 and 10:1 signal-to-noise ratio, respectively. All experiments were performed in triplicate. The optimal saponification procedure was a concentration of 25% KOH at either 40 or 50°C. Saponified extracts solubilized in solutions containing diethyl ether had greater concentrations of lutein- than hexane- or tetrahydrofuran-based solutions, with peak areas above LoQ values. The solution containing diethyl ether solubilized similar concentrations of retinol, α-tocopherol, and β-carotene when compared with other solutions. The proposed optimized method allows for the simultaneous determination of carotenoids from milk with increased lutein and zeaxanthin sensitivity without sacrificing recovery of retinol, α-tocopherol, and β-carotene.

Influences of different storage environments and packaging materials on the quality of the traditional Chinese health food Herba Menthae Haplocalycis

Abstract Herba Menthae Haplocalycis(HMH) is a traditional Chinese health food that is commonly used in the food industry, as well as numerous other industries. As the demand for HMH is increasing dramatically, a greater number of people are paying close attention to the quality of HMH. In this paper, we describe the establishment of an effective ultra high performance liquid chromatography – photo diode array (UPLC-PDA) method to study the effect of different storage environments (low temperature and humidity, normal temperature and humidity, high temperature and humidity) and packaging materials (ziplock bags, braided bags, kraft paper) on the HMH quality. The results from this study demonstrated that storage environments and packaging materials both influence the quality of HMH. The contents of hesperidin, diosimin, diosmetin-7-O-β- d -glucopyranoside, didymin and buddleoside were significantly affected when stored under conditions with normal temperature and humidity (P 0.05) and ziplock bag storage (P > 0.05). Furthermore, we found that the contents of the eight components were decreased less at low temperature and humidity and in ziplock bags, compared to other storage environments and packaging materials. In addition, no mycotoxins were detected. These results indicate that low temperature and humidity and ziplock bag storage conditions are beneficial for maintaining HMH quality. This present study may provide a scientific basis for the quality control and establishment of novel storage specifications for HMH.

Simultaneous determination of ten compounds in two main medicinal plant parts of Tibetan herb, &lt;i&gt;Pterocephalus hookeri&lt;/i&gt; (CB Clarke) Höeck, by ultra-high performance liquid chromatography-photodiode array

Purpose: To develop an ultra-high performance liquid chromatography (UPLC) - photodiode array (PDA) method to compare the chemical composition of two different medicinal components of Pterocephalus hookeri.Methods: Samples were chromatographically separated in succession using Waters Acquity UPLCR BEH C18 column (2.1 × 100 mm, 1.7 μm) and gradient elution (0.2 % phosphoric acid aqueous -acetonitrile). Using partial least squares discriminant analysis and one-way analysis of variance, attempts were made to distinguish different medicinal parts of P. hookeri.Results: Regression equation for 10 compounds showed good linear regression (R2 &gt; 0.9994). The relative standard deviations of precision, stability, repeatability and recovery were under 5 %. Compared with the aerial plant part, the root had significantly higher levels of sylvestroside I (p &lt; 0.01), cantleyoside (p &lt; 0.001), dipsanosides B (p &lt; 0.01) and dipsanosides A (p &lt; 0.01), but significantly lower levels of loganic acid (p &lt; 0.001), chlorogenic acid (p &lt; 0.01), and isochlorogenic acid (p &lt; 0.01). There were no significant differences between loganin, sweroside and isochlorogenic acid C.Conclusion: The described method is simple, accurate and reproducible, and can be used for the simultaneous determination of 10 major compounds of P. hookeri. The results demonstrate that there is variation in the chemical composition of the aerialpart and root of P. hookeri and that loganic acid and cantleyoside are the primary chemical biomarkers.Keywords: Tibetan medicine, Pterocephalus hookeri, Medicinal parts, Loganic acid and Cantleyoside, UPLC-PDA

Application of Response Surface Methodology for Optimisation of Simultaneous UHPLC-PDA Determination of Oleanolic and Ursolic Acids and Standardisation of Ericaceae Medicinal Plants

A fast and sensitive ultra-high performance liquid chromatography-photodiode array (UHPLC-PDA) method for simultaneous quantification of oleanolic acid (OA) and ursolic acid (UA) in plant materials was developed. A central composite design combined with a response surface methodology was utilized to establish optimal separation conditions. The final separation was accomplished on a Zorbax Eclipse XDB-C18 column (1.8 μm, 100 mm × 3 mm I.D., Agilent, Santa Clara, CA, USA) using a mixture 90:10 (v/v) of methanol and 1% (w/v) aqueous orthophosporic acid as a mobile phase at a flow rate of 0.44 mL/min and temperature of 18 °C. The analysis was completed in 6.2 min with satisfactory resolution of 1.5 between the target analytes. The developed method proved to be precise (relative standard deviations below 3.2%), accurate (recoveries in the range of 95.27%–98.60%), and sensitive (limits of detection (LODs) in the range of 0.047–0.051 mg/mL). The method was then successfully applied to evaluate OA and UA content in real samples of selected Ericaceae plant materials (leaves of Arctostaphylos uva ursi, Vaccinium myrtillus, Vaccinium vitis idaea, Gaultheria procumbens). The content of OA and UA in investigated samples varied in the range of 0.74–4.47 mg/g dry weight (dw) and 1.30–18.61 mg/g dw, respectively.

Polyketides, toxins and pigments in Penicillium marneffei.

Penicillium marneffei (synonym: Talaromyces marneffei) is the most important pathogenic thermally dimorphic fungus in China and Southeastern Asia. The HIV/AIDS pandemic, particularly in China and other Southeast Asian countries, has led to the emergence of P. marneffei infection as an important AIDS-defining condition. Recently, we published the genome sequence of P. marneffei. In the P. marneffei genome, 23 polyketide synthase genes and two polyketide synthase-non-ribosomal peptide synthase hybrid genes were identified. This number is much higher than those of Coccidioides immitis and Histoplasma capsulatum, important pathogenic thermally dimorphic fungi in the Western world. Phylogenetically, these polyketide synthase genes were distributed evenly with their counterparts found in Aspergillus species and other fungi, suggesting that polyketide synthases in P. marneffei did not diverge from lineage-specific gene duplication through a recent expansion. Gene knockdown experiments and ultra-high performance liquid chromatography-photodiode array detector/electrospray ionization-quadruple time of flight-mass spectrometry analysis confirmed that at least four of the polyketide synthase genes were involved in the biosynthesis of various pigments in P. marneffei, including melanin, mitorubrinic acid, mitorubrinol, monascorubrin, rubropunctatin, citrinin and ankaflavin, some of which were mycotoxins and virulence factors of the fungus.

Quantification of patulin in fruit leathers by ultra-high-performance liquid chromatography-photodiode array (UPLC-PDA)

Patulin is a mycotoxin commonly found in certain fruit and fruit products. For this reason many countries have established regulatory limits pertaining to, in particular, apple juice and apple products. Fruit leathers are produced by dehydrating fruit puree, leaving a sweet product that has a leathery texture. A recent report in the literature described the detection of patulin at substantial levels in fruit leathers. To investigate this further, an ultra-high-performance liquid chromatography-photodiode array (UPLC-PDA) method was developed for the sensitive detection of patulin in fruit leathers. Investigations were also made of the suitability of direct analysis in real time-mass spectrometry (DART-MS) for detection of patulin from the surface of fruit leathers. Results indicated DART-MS was insufficiently sensitive for quantification from the surface of home-style apple leathers, although patulin spiked onto the surface of leather or peel could be detected. The UPLC-PDA method was used to determine the fate of patulin during the preparation of home-made fruit leathers. Interestingly, when a home-style process was used, the patulin was not destroyed, but rather increased in concentration as the puree was dehydrated. The UPLC-PDA method was also used to screen for patulin in commercial fruit leathers. Of the 36 products tested, 14 were above the limit of detection (3.5 μg kg–1) and nine were above the limit of quantification (12 μg kg–1). Positive samples were confirmed by UPLC-MS/MS. Only one sample was found above the US regulatory limit for single-strength apple juice products (50 μg kg–1). These results suggest patulin can be concentrated during preparation and can be found in fruit leathers. The limited survey suggests that patulin is fairly prevalent in such commercial products, but that the levels are usually low.

Enhanced production of nargenicin A(1) and generation of novel glycosylated derivatives.

Nargenicin A1, an antibacterial polyketide macrolide produced by Nocardia sp. CS682, was enhanced by increasing the pool of precursors using different sources. Furthermore, by using engineered strain Nocardia sp. ACC18 and supplementation of glucose and glycerol, enhancement was ~7.1 fold in comparison to Nocardia sp. CS682 without supplementation of any precursors. The overproduced compound was validated by mass spectrometry and nuclear magnetic resonance analyses. The novel glycosylated derivatives of purified nargenicin A1 were generated by efficient one-pot reaction systems in which the syntheses of uridine diphosphate (UDP)-α-D-glucose and UDP-α-D-2-deoxyglucose were modified and combined with glycosyltransferase (GT) from Bacillus licheniformis. Nargenicin A1 11-O-β- D-glucopyranoside, nargenicin A1 18-O-β-D-glucopyranoside, nargenicin A111 18-O-β-D- diglucopyranoside, and nargenicin 11-O-β-D-2-deoxyglucopyranoside were generated. Nargenicin A1 11-O-β-D-glucopyranoside was structurally elucidated by ultra-high performance liquid chromatography-photodiode array (UPLC-PDA) conjugated with high-resolution quantitative time-of-flight-electrospray ionization mass spectroscopy (HR-QTOF ESI-MS/MS), supported by one- and two-dimensional nuclear magnetic resonance studies, whereas other nargenicin A1 glycosides were characterized by UPLC-PDA and HR-QTOF ESI-MS/MS analyses. The overall conversion studies indicated that the one-pot synthesis system is a highly efficient strategy for production of glycosylated derivatives of compounds like macrolides as well. Furthermore, assessment of solubility indicated that there was enhanced solubility in the case of glycoside, although a substantial increase in activity was not observed.

Determination of flavonol glycosides in tea samples by ultra-high performance liquid chromatography-photodiode array detection-tandem mass spectrometry

An ultra-high performance liquid chromatography-photodiode array detection-tandem mass spectrometry (UPLC-PDA-MS/MS) method was developed for the determination of flavonol glycosides in tea samples. The chromatographic separation was performed on an UPLC HSS T3 column by gradient elution with the mobile phases of acetonitrile and water both containing 0.1% (v/v) formic acid. A total of 15 flavonol glycosides which include 3 myricetin glycosides, 6 quercetin glycosides and 6 kaempferol glycosides were positively identified in green and black tea samples by comparing the retention times and mass spectra of the samples with standards and publications. The quantities of flavonol glycosides were relatively calculated with the stand- ard quercetin-3-rhamnosylglucoside (Q-GRh) which was calibrated with external quantification method using multi-reaction monitoring (MRM) mode. The results showed that there were different flavonol glycoside distributions in green tea and black tea. The total amount of flavonol glycosides in green tea was 1. 7 times of that in black tea. The major flavonol glycosides in green tea were myricetin-3-galactoside (M-Ga), myricetin-3-glucoside (M-G), quercetin-3-glucosyl-rhamnosyl-galactoside (Q-GaRhG), quercetin-3-glucosyl-rhamnosyl-glucoside (Q-GRhG), kaempferol-3-glucosyl-rhamnosyl-galactoside (K-GaRhG) and kaempferol-3-glucosyl- rhamnosyl-glucoside (K-GRhG), but for black tea, the major flavonol glycosides were quercetin-3-rhamnosylglucoside (Q-GRh), quercetin-3-glucoside (Q-G), kaempferol-3-rhamnosylglucoside (K-GRh) and kaempferol-3-galactoside (K-Ga). The present method is accurate, convenient for the rapid identification of flavonol glycosides and analysis of constituent distribution for green and black teas.

Analysis of palmitoyl apo-astaxanthinals, apo-astaxanthinones, and their epoxides by UHPLC-PDA-ESI-MS.

Food products enriched with fatty acid-esterified xanthophylls may result in deviating dietary apo-carotenoids. Therefore, free astaxanthin and its mono- and dipalmitate esters were subjected to two degradation processes in a methanolic model system: light-accelerated autoxidation and hypochlorous acid/hypochlorite (HOCl/OCl(-)) bleaching. Reversed phase ultrahigh-performance liquid chromatography photodiode array with in-line electrospray ionization mass spectrometry (RP-UHPLC-PDA-ESI-MS) was used for assessment of degradation products. Apo-astaxanthinals and -astaxanthinones containing 3 (apo-9) to 10 (apo-8') conjugated double bonds were found upon autoxidation for all three types of astaxanthin (except free apo-8'-astaxanthinal). Fragmentation of [M + H](+) and [M + Na](+) parent masses of apo-astaxanthins from dipalmitate astaxanthin indicated palmitate esterification. Astaxanthin monopalmitate degradation resulted in a mixture of free and palmitate apo-astaxanthins. HOCl/OCl(-) rapidly converted the astaxanthins into a mixture of epoxy-apo-9- and epoxy-apo-13-astaxanthinones. The palmitate ester bond was hardly affected by autoxidation, whereas for HOCl/OCl(-) the ester bond of the apo-astaxanthin palmitoyl esters was degraded.

Enzymatic synthesis of epothilone A glycosides

Epothilones are extremely cytotoxic chemotherapeutic agents with epoxide, thiazole, and ketone groups that share equipotent kinetic similarity with taxol. The in vitro glycosylation catalyzed by uridine diphosphate glucosyltransferase (YjiC) from Bacillus licheniformis generated six novel epothilone A glycoside analouges including epothilone A 7-O-β-D-glucoside, epothilone A 7-O-β-D-galactoside, epothilone A 3,7-O-β-D-digalactoside, epothilone A 7-O-β-D-2-deoxyglucoside, epothilone A 7-O-β-L-rhamnoside, and epothilone A 7-O-β-L-fucoside. Epothilone A 7-O-β-D-glucoside was structurally elucidated by ultra-high performance liquid chromatography-photo diode array (UPLC-PDA) conjugated with high resolution quantitative time-of-flight-electrospray ionization mass spectroscopy (HR-QTOF ESI-MS/MS) supported by one-and two-dimensional nuclear magnetic resonance studies whereas other epothilone A glycosides were characterized by UPLC-PDA and HR-QTOF ESI-MS/MS analyses. The time dependent conversion study of epothilone A to epothilone A 7-O-β-D-glucoside found to be maximum (~26%) between 3 h to 5 h incubation.

Profiling Polyphenols in Five Brassica Species Microgreens by UHPLC-PDA-ESI/HRMSn

Brassica vegetables are known to contain relatively high concentrations of bioactive compounds associated with human health. A comprehensive profiling of polyphenols from five Brassica species microgreens was conducted using ultrahigh-performance liquid chromatography photodiode array high-resolution multistage mass spectrometry (UHPLC-PDA-ESI/HRMS(n)). A total of 164 polyphenols including 30 anthocyanins, 105 flavonol glycosides, and 29 hydroxycinnamic acid and hydroxybenzoic acid derivatives were putatively identified.The putative identifications were based on UHPLC-HRMS(n) analysis using retention times, elution orders, UV-vis and high-resolution mass spectra, and an in-house polyphenol database as well as literature comparisons. This study showed that these five Brassica species microgreens could be considered as good sources of food polyphenols.

Applicability of accelerated solvent extraction for synthetic colorants analysis in meat products with ultrahigh performance liquid chromatography–photodiode array detection

Accelerated solvent extraction (ASE) coupled with ultrahigh performance liquid chromatography (UHPLC) with photodiode array detection (PDA) has been used for the quantitative determination of synthetic colorants in meat products. Samples were extracted with ethanol–water–ammonia with a ratio of 75:24:1 (v/v/v) using ASE instrument at 85°C. As a result, all the colorants in meat products were separated using an optimized gradient elution within 3.5min. Detection and quantification limits of synthetic colorants were in the ranges of 0.01–0.02mgkg−1 and 0.05mgkg−1, respectively. The intra-day and inter-day precision of the synthetic colorants were ranged between 1.7% (E123) to 5.2% (E124) and 3.2% (E124) to 6.0% (E129), respectively. The intra-day and inter-day recoveries of the synthetic colorants were ranged between 76.9% (E124) to 84.9% (E102) and 76.3% (E124) to 84.3% (E127), respectively. The method has been applied for the determination of seven synthetic colorants in meat products.

A fast method using a new hydrophilic–lipophilic balanced sorbent in combination with ultra-high performance liquid chromatography for quantification of significant bioactive metabolites in wines

This manuscript describes the development and validation of an ultra-fast, efficient, and high throughput analytical method based on ultra-high performance liquid chromatography (UHPLC) equipped with a photodiode array (PDA) detection system, for the simultaneous analysis of fifteen bioactive metabolites: gallic acid, protocatechuic acid, (−)-catechin, gentisic acid, (−)-epicatechin, syringic acid, p-coumaric acid, ferulic acid, m-coumaric acid, rutin, trans-resveratrol, myricetin, quercetin, cinnamic acid and kaempferol, in wines. A 50-mm column packed with 1.7-μm particles operating at elevated pressure (UHPLC strategy) was selected to attain ultra-fast analysis and highly efficient separations. In order to reduce the complexity of wine extract and improve the recovery efficiency, a reverse-phase solid-phase extraction (SPE) procedure using as sorbent a new macroporous copolymer made from a balanced ratio of two monomers, the lipophilic divinylbenzene and the hydrophilic N-vinylpyrrolidone (Oasis™ HLB), was performed prior to UHPLC–PDA analysis. The calibration curves of bioactive metabolites showed good linearity within the established range. Limits of detection (LOD) and quantification (LOQ) ranged from 0.006μgmL−1 to 0.58μgmL−1, and from 0.019μgmL−1 to 1.94μgmL−1, for gallic and gentisic acids, respectively. The average recoveries±SD for the three levels of concentration tested (n=9) in red and white wines were, respectively, 89±3% and 90±2%. The repeatability expressed as relative standard deviation (RSD) was below 10% for all the metabolites assayed. The validated method was then applied to red and white wines from different geographical origins (Azores, Canary and Madeira Islands). The most abundant component in the analysed red wines was (−)-epicatechin followed by (−)-catechin and rutin, whereas in white wines syringic and p-coumaric acids were found the major phenolic metabolites.The method was completely validated, providing a sensitive analysis for bioactive phenolic metabolites detection and showing satisfactory data for all the parameters tested. Moreover, was revealed as an ultra-fast approach allowing the separation of the fifteen bioactive metabolites investigated with high resolution power within 5min.