Liquid Chromatography-electrospray Ionization-quadrupole-time Of Flight-mass Spectrometry Research Articles

HPLC-ESI-QTOF-MS/MS Analysis of Artemisia cina Leaves Aqueous Extract and Flavonoid Isolation Using High-speed Countercurrent Chromatography

Artemisia cina Berg ex Poljakov, a shrubby plant endemic to the semi-arid areas of Kazakhstan, has as a long history of being used in traditional medicines as an antitumour, antifungal and anthelmintic agent. In a preliminary study carried out on different methodologies to produce aqueous extracts of A. cina it was seen that a simple aqueous extract of A. cina (as in an infusion of the plant) had the strongest anti-SARS-CoV-2 activity. The profiling of this aqueous extract was performed using Liquid Chromatography-Electrospray Ionization-Quadrupole-Time-of-Flight Mass Spectrometry (LC-ESI-Q-TOF-MS) while High-Speed Countercurrent Chromatography (HSCCC) and a Sephadex LH-20 column were utilised to isolate and purify the extract in ethyl acetate obtained from the aqueous extract. Nuclear Magnetic Resonance (NMR) was used for structural elucidation. The flavonoid spinacetin-7-O-glucoside was found to be one of the main compounds present in the A. cina aqueous extract. With the emergence of the COVID-19 pandemic and the frequency in which new COVID strains occur, the demand for drugs with anti-SARS-CoV-2 activity is at an all-time high. Flavonoids and artemisinin identified by LC-MS in this extract are hypothesised to be the key compounds behind the anti-SARS-CoV-2 activity of the aqueous extract, however this needs to be further tested and explored.

Structural and functional analysis of a novel galactose-binding lectin derived from Chlorella sorokiniana MW769776

A freshwater green microalgal strain was isolated and the lectin was identified in it by a strong hemagglutination activity (HA) assay. Characterization of the algal strain was found to be Chlorella sorokiniana (MW769776). A single step affinity chromatographic technique was developed to purify Chlorella sorokiniana lectin (CSL) using guar gum as the affinity matrix. The precipitate showed a single active peak with a titer value of 1024 HU, with a concentration of 1111 U, and a purification fold of 9. The purified protein exhibited a single band in SDS-PAGE with a molecular weight of 16 kDa. Analysis by liquid chromatography-electrospray ionization-quadrupole-time of flight mass spectrometry (LC-ESI-Q-TOF-MS) of tryptic-digested purified lectin showed that it was a monomeric protein. A multiple sequence alignment analysis revealed that the peptide sequences of CSL exhibited similarity with the H-type lectin domain of Micractinium conductrix. The structure of CSL was studied by FTIR and homology modeling methods, indicating the presence of α-helix as well as β-sheet in its secondary structure. Whereas the 3D structure exhibited the similarity with the core protein of light-harvesting reaction center complex of photosystem I. The significance of this study suggests that the characteristics of CSL are consistent with its identification as a hemagglutinin, a type of novel lectin, which suggests its candidature for various biological purposes. Communicated by Ramaswamy H. Sarma

Iridoid- and flavonoid-enriched fractions of Cornus sanguinea and Cornus mas exert antioxidant and anti-inflammatory effects and inhibit key enzymes in the treatment of metabolic disorders.

Background: Berry fruits are recognized as a "superfood" due to their high content of bioactive compounds and health benefits. Scope and approach: Herein, extracts of Cornus sanguinea and Cornus mas fresh and dried fruits obtained by different extraction procedures (ethanolic and hydroalcoholic maceration, ultrasound-assisted extraction, and Soxhlet apparatus) were analysed using liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry (LC-ESI-QTOF-MS) and compared to identify the main healthy compounds and their impact on the inhibition of key enzymes (pancreatic lipase, α-glucosidase, and α-amylase) associated with metabolic disorders. The antioxidant activity and inhibition of nitric oxide (NO) and NF-κB pathway were also investigated. Key findings and conclusions: Flavonoids, iridoids, and phenolic acids were the main classes of identified compounds. Herein, kaempferol 3-O-galactoside, kaempferol 3-O-glucoside, quercetin, quercetin 3-O-xyloside, and myricetin 3-O-galactoside were detected for the first time in C. sanguinea. Remarkable antioxidant effects and promising α-glucosidase and lipase inhibitory activity were observed with extracts obtained by hydroalcoholic maceration of both Cornus dried fruits. Consequently, these extracts were subjected to fractionation using Amberlite XAD-16 resin. The most promising biological activities, which are attributed to the presence of some flavonoids and iridoids, were detected with the C. sanguinea fractions, in particular SD2(II). The results of this study offer new insights into the potential development of functional foods, nutraceuticals, and food supplements using the Cornus species.

Cumyl-CBMICA: A new synthetic cannabinoid receptor agonist containing a cyclobutyl methyl side chain.

Since the beginning of the phenomenon of new psychoactive substances (NPS), synthetic cannabinoid receptor agonists (SCRAs) have been the largest and most prevalent subclass of these drugs in Europe. Many countries implemented specific legislation scheduling classes of substances defined on the basis of their chemical structure to reduce supply. We describe the identification and analytical characterization within the EU project ADEBAR plus of 1-(cyclobutylmethyl)-N-(2-phenylpropan-2-yl)-1H-indole-3-carboxamide which resulted in the formal notification through the Early Warning System of the European Monitoring Centre for Drug and Drug Addiction (EMCDDA). This is the first identification of this new SCRA worldwide and the analytical data was distributed (inter-)nationally right after identification in 2019. First, the substance was isolated from the herbal material using preparative high-performance liquid chromatography (HPLC). Structure elucidation and analytical characterization were performed using gas chromatography-mass spectrometry (GC-MS), gas chromatography-solid state infrared spectroscopy (GC-sIR), liquid chromatography-electrospray ionization-quadrupole time of flight-mass spectrometry (LC-ESI-qToF-MS), Raman spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. The new compound contains a cyclobutyl methyl group as a side chain and has not been described in any patent to our knowledge. Based on the semisystematic nomenclature of SCRAs, we propose Cumyl-CBMICA as a short name for the compound.

Natural Deep Eutectic Solvent as Extraction Media for the Main Phenolic Compounds from Olive Oil Processing Wastes.

In this new century, sustainable development challenges chemical sciences to develop new and clean technological processes. The agri-food industry produces significant quantities of waste, raising significant economic and environmental concerns. Food waste valorization using environmentally friendly procedures is of increasing importance. This study describes the use of several Natural Deep Eutectic Solvents (NADESs) for the microwave-assisted extraction (MAE) of valuable bioactive phenolic compounds from olive oil processing wastes. The extracted samples were characterized by liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF/MS) analysis and the quantification of the phenolic compounds was performed by HPLC analysis. The obtained data were compared with those obtained using water as the solvent in the same extraction conditions. The extraction process is nontoxic, simple and selective and meets most of the criteria to be considered as a sustainable process, with the solvents arising directly from nature.

Susceptibility and resistance of Sporothrix brasiliensis to branded and compounded itraconazole formulations.

Itraconazole is the first drug of choice for the treatment of sporotrichosis and it is available at different concentrations for veterinary patients. However, therapeutic failure has been reported, limiting clinical treatment. This study evaluated the in vitro efficacy of brand-name and compounded itraconazole formulations against Sporothrix brasiliensis and estimated the itraconazole content in each tested formulation. Oral capsules were acquired from two brand-name products for human (H-IND) and veterinary (V-IND) uses, and three from compounding pharmacies in Pelotas, RS, for human (H-COMP1/H-COMP2) and veterinary (V-COMP) uses. Capsule purity was analyzed by liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS). Antifungal activity was determined against 29 Sporothrix brasiliensis by the M38-A2 guideline of CLSI. H-IND/H-COMP1/H-COMP2 had high efficacy against S. brasiliensis (approximately 70% of total isolated susceptible), V-COMP showed moderate efficacy (51.7%), and V-IND was the least effective formulation (37.9%). Thirty-four percent of the total isolates were resistant to all formulations. Furthermore, itraconazole content did not match the concentration indicated by the manufacturers, ranging from 387.70 to 7.81μg/mg (H-COMP2 > V-COMP > H-IND > H-COMP1 > V-IND). Therefore, it is possible that the formulations showed different in vitro efficacy due to the difference in their itraconazole contents. Given the emergence of antifungal resistance for all formulations, the choice product to be used must follow susceptibility testing. Stringent quality control measures are recommended for product manufactures to assure drug content uniformity.

Ultrasound-assisted one-phase solvent extraction coupled with liquid chromatography-quadrupole time-of-flight mass spectrometry for efficient profiling of egg yolk lipids

In this research, a novel ultrasound-assisted extraction (USAE) method using a one-phase solvent (isopropanol, IPA) combined with liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QToF-MS) was developed for exhaustive profiling of egg yolk lipids, which are considered to be essential nutrients that have important functions for human health. Compared with IPA-vortex extraction method, the optimized IPA-USAE method shows better performance in terms of extraction time, lipid losses, lipid recoveries and the number of lipids identified. With this established simple, high throughput and reliable analytical approach, untargeted comprehensive lipid profiling of four kinds of egg yolks was achieved, thus providing a powerful tool for nutritional research of egg lipids. Considering that the lipids contained in egg yolk are quite abundant in both quantity and species, the proposed IPA-USAE combined with LC-ESI-QToF-MS is also potentially applicable to comprehensive extraction and profiling of lipids in other biological samples.

Contribution of Flavonoids and Iridoids to the Hypoglycaemic, Antioxidant, and Nitric Oxide (NO) Inhibitory Activities of Arbutus unedo L.

This study aims at investigating the contribution of two classes of compounds, flavonoids and iridoids, to the bioactivity of Arbutus unedo L. leaves and fruits. The impact of different extraction procedures on phytochemicals content and hypoglycemic, antioxidant, and nitric oxide (NO) inhibitory activities of A. unedo fresh and dried plant materials was investigated. Ellagic acid 4-O-β-D-glucopyranoside, kaempferol 3-O-glucoside, and norbergenin were identified for the first time in this genus by using liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry (LC-ESI-QTOF-MS). Three iridoids (gardenoside, geniposide, unedoside) are specifically identified in the leaves. Interestingly, asperuloside was extracted only from dried fruits by ethanol with Soxhlet apparatus. Extracts were screened for their potential antioxidant activities by using the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), Ferric Reducing Activity Power (FRAP), and β-carotene bleaching tests. Based on the Global Antioxidant Score (GAS) calculation, the most promising antioxidant extract was obtained by hydroalcoholic maceration of dried leaves that showed half maximal inhibitory concentration (IC50) of 0.42 and 0.98 μg/mL in ABTS and DPPH assays, respectively. The hypoglycaemic activity was investigated by α-amylase and α-glucosidase inhibition tests. Extracts obtained by ethanol ultrasound extraction of fresh leaves and hydroalcoholic maceration of fresh fruits (IC50 of 19.56 and 28.42 μg/mL, respectively) are more active against α-glucosidase than the positive control acarbose (IC50 of 35.50 μg/mL). Fruit extracts exhibited the highest anti-inflammatory activity.

LC-ESI-QTOF-MS profiling, protective effects on oxidative damage, and inhibitory activity of enzymes linked to type 2 diabetes and nitric oxide production of Vaccinium corymbosum L. (Ericaceae) extracts

BACKGROUND: Berries are worldwide recognized as “superfoods” due to the high content of bioactive compounds and the health benefits deriving from their consumption. OBJECTIVE: The present study was planned to assess and to compare the chemical profile and the in vitro antioxidant, hypoglycaemic, and anti-inflammatory activities of Vaccinium corymbosum L. berries and leaves extracts obtained by different extraction procedures. Ethanol was chosen as solvent because it is a GRAS (Generally Recognized As Safe) and widely used for the extraction of polar compounds. METHODS: Different extraction techniques such asmaceration, ultrasound-assisted extraction, Soxhlet extractor and decoction, have been applied by using food grade ethanol/water as solvent mixture, selected as environmentally friendly solvents. Extracts obtained from fruits and leaves were chemically investigated by liquid chromatography-electrospray ionization quadrupole-time of flight-mass spectrometry (LC-ESI-QTOF-MS) and for their potential in vitro antioxidant, hypoglycaemic, and anti-inflammatory effects. RESULTS: Some iridoids were detected for the first time in V. corymbosum. Dried leaves extracted by decoction and ethanol with Soxhlet apparatus showed the highest 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals scavenging activity with IC50 value of 0.77μg/mL, which is 2.2-time lower than that positive control ascorbic acid. A promising inhibition of the production of nitrate/nitrite, critical mediators of inflammation, was found. The decoction of berries showed the highest activity in counteracting nitric oxide (NO.) production. Furthermore, two leaves extracts (decoction of dried leaves and hydroalcoholic maceration of fresh leaves) were particularly active as α-amylase inhibitors with IC50 values of 16.16 and 20.55 μg/mL, respectively. CONCLUSIONS: This work could provide valuable basis for future research on V. corymbosum to improve recovery of specific active compounds such as flavonoids and iridoids

LC-ESI-QTOF/MS Characterization of Phenolic Compounds in Palm Fruits (Jelly and Fishtail Palm) and Their Potential Antioxidant Activities.

Palm fruits have gained growing attention for their nutrition values and health promotion perspectives. They have a diverse range of bioactive compounds including carotenoids, vitamins, dietary fibres and especially polyphenolic compounds. These polyphenolic compounds contribute to the putative health benefits of palm fruits. Nevertheless, the detailed information about these polyphenols in palm fruits is limited. The present work was conducted to comprehensively characterize polyphenols in two palm fruits, jelly palm (Butia ordorata) and fishtail palm (Caryota uren), using liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF/MS) and assess their antioxidant potential. The total phenolic content (TPC), total tannins content (TTC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant assay and 2,2′-azinobis-(3-ethylbenzo-thiazoline-6-sulfonic acid) (ABTS) scavenging abilities and ferric reducing antioxidant power (FRAP) were higher in the jelly palm fruit while total flavonoid contents (TFC) were higher in the fishtail palm. The LC-ESI-QTOF/MS tentatively identified a total of 86 phenolic compounds in both jelly and fishtail palm fruits. Although both palm fruits exhibited different phenolic profiles, hydroxycinnamic acids and flavonols were the most common in both. In high performance liquid chromatography photodiode array (HPLC-PDA) quantification, 4-hydroxybenzoic acid (317.46 ± 4.68 µg/g) and catechin (4724.00 ± 32.39 µg/g) were the most abundant phenolic acid and flavonoid quantified in the jelly palm fruit, respectively. Quercetin (557.28 ± 7.81 µg/g) and kaempferol 3-O-glucoside (220.99 ± 2.06 µg/g) were the most abundant flavonoids quantified in the fishtail palm. Our study indicates that palm fruit is a good source of polyphenols and has strong antioxidant potential for health promotion. Furthermore, this study provides the scientific basis for an exploitation of jelly and fishtail palm fruits in the food, pharmaceutical and nutraceutical industries.

Depolymerization of Laccase-Oxidized Lignin in Aqueous Alkaline Solution at 37 °C

Lignin depolymerization is a coveted process for the generation of high-value compounds from a low-cost feedstock. This report describes a chemoenzymatic approach for the depolymerization of lignin involving a laccase-catalyzed oxidation under ambient air at room temperature followed by a base (NaOH)-induced depolymerization in aqueous solution at 37 °C. Two-dimensional nuclear magnetic resonance heteronuclear single quantum coherence spectroscopy, gel permeation chromatography, and liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry (LC-ESI-Q-TOF-MS) analysis indicated the degradation of lignin and the formation of water-soluble fractions containing guaiacol, syringol, vanillic acid, m-anisic acid, and veratric acid. Furthermore, guaiacol and veratric acid are the main final products in the chemoenzymatic decomposition of a β-O-4 model compound.

Urinary metabolic profiles after vitamin D2 versus vitamin D3 supplementation in prediabetes

AimTo assess the potential biological differences between vitamin D2 and D3 using urinary metabolite profiles in response to vitamin D3 or D2 supplementation. MethodSubjects consisted of 29 subjects with impaired fasting glucose and/or impaired glucose tolerance. Subjects were randomized into two groups, vitamin D2 (20,000 IU weekly, n = 14) or vitamin D3 (15,000 IU weekly, n = 15). Urine and serum samples were taken at two different time points for each subject (at baseline and at 12 weeks). Urinary metabolite profiling was performed by liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS). Serum calcium was analyzed on an automated biochemical analyzer and serum intact parathyroid hormone was determined by electrochemiluminescence immunoassay. ResultsAt baseline, there was no statistically significant difference in clinical characteristics including age, gender, body mass index, waist circumference and 25-hydroxyvitamin D (25(OH)D) levels between the 2 groups. Weekly administration of 20,000 U D2 for 12 weeks resulted in comparable 25(OH)D concentrations as compared to weekly 15,000 U D3 supplementation (97.8 ± 305 vs. 96.8 ± 3.4 nmol/L, p = 0.84). No difference in serum calcium (2.3 ± 0.03 vs. 2.2 ± 0.03 nmol/L, p = 0.52) or intact parathyroid hormone (5.3 ± 0.3 vs. 4.9 ± 0.5 pmol/L, p = 0.54) at 12 weeks was found. Principle component analysis did not reveal apparent segregation of metabolites according to D2 or D3 supplementation. Moreover, using partial least square regression, no apparent separation between the D2 and the D3 group was found. No important metabolite influencing the separation of the D2 from the D3 group was found using variables importance on projection analysis. ConclusionsAt comparable circulating 25(OH)D concentrations, vitamin D2 or D3 supplementation does not appear to result in different urinary metabolite profiles. Our finding does not support a biological difference between vitamin D2 and D3.

Isolation and identification of an antioxidant collagen peptide from skipjack tuna (Katsuwonus pelamis) bone.

To date, many researchers have developed active components that are derived from seafood processing for the purposes of healthcare. Here, an antioxidant collagen peptide was obtained from skipjack tuna (Katsuwonus pelamis) bone by using a combination of trypsin and chymotrypsin as the catalyst. The amino acid sequence of the peptide was identified as Ser–Ser–Gly–Pro–Pro–Val–Pro–Gly–Pro–Met–Gly–Pro–Met–Gly–Pro–Arg (SSGPPVPGPMGPMGPR) by liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS) analysis. We found that the as-prepared collagen peptide can efficiently scavenge DPPH radical (IC50 3.149 mM), superoxide anion radical (IC50 3.803 mM) and ABTS radical (IC50 9.489 mM). In addition, it has been found that the methionine (Met) residue in the collagen peptide could provide a precise active site during the scavenging of DPPH radicals by Fourier transform infrared spectroscopy (FTIR) analysis and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry analysis. These results suggest that the peptide can find wide uses in the food, cosmetic and pharmaceutical industries.

Phase I metabolism of the carbazole-derived synthetic cannabinoids EG-018, EG-2201, and MDMB-CHMCZCA and detection in human urine samples.

Synthetic cannabinoids (SCs) are a structurally diverse class of new psychoactive substances. Most SCs used for recreational purposes are based on indole or indazole core structures. EG-018 (naphthalen-1-yl(9-pentyl-9H-carbazol-3-yl)methanone), EG-2201 ((9-(5-fluoropentyl)-9H-carbazol-3-yl)(naphthalen-1-yl)methanone), and MDMB-CHMCZCA (methyl 2-(9-(cyclohexylmethyl)-9H-carbazole-3-carboxamido)-3,3-dimethylbutanoate) are 3 representatives of a structural subclass of SCs, characterized by a carbazole core system. In vitro and in vivo phase I metabolism studies were conducted to identify the most suitable metabolites for the detection of these substances in urine screening. Detection and characterization of metabolites were performed by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) and liquid chromatography-electrospray ionization-quadrupole time-of-flight-mass spectrometry (LC-ESI-QToF-MS). Eleven in vivo metabolites were detected in urine samples positive for metabolites of EG-018 (n=8). A hydroxypentyl metabolite, most probably the 4-hydroxypentyl isomer, and an N-dealkylated metabolite mono-hydroxylated at the carbazole core system were most abundant. In vitro studies of EG-018 and EG-2201 indicated that oxidative defluorination of the 5-fluoropentyl side chain of EG-2201 as well as dealkylation led to common metabolites with EG-018. This has to be taken into account for interpretation of analytical findings. A differentiation between EG-018 and EG-2201 (n=1) uptake is possible by the detection of compound-specific in vivo phase I metabolites evaluated in this study. Out of 30 metabolites detected in urine samples of MDMB-CHMCZCA users (n=20), a metabolite mono-hydroxylated at the cyclohexyl methyl tail is considered the most suitable compound-specific consumption marker while a biotransformation product of mono-hydroxylation in combination with hydrolysis of the terminal methyl ester function provides best sensitivity due to its high abundance.

Structural characterization and pharmacological evaluation of the new synthetic cannabinoid CUMYL-PEGACLONE.

The number of new psychoactive substances (NPS) that have emerged on the European market has been rapidly growing in recent years, with a particularly high number of new compounds from the group of synthetic cannabinoid receptor agonists. There have been various political efforts to control the trade and the use of NPS worldwide. In Germany, the Act to control the distribution of new psychoactive substances (NpSG) came into force in November 2016. In this new act, two groups of substances were defined, the group "cannabimimetics/synthetic cannabinoids" covering indole, indazole, and benzimidazole core structures, and a second group named "compounds derived from 2-phenethylamine." Shortly after, the first retailers of "herbal blends" promoted new products allegedly not violating the German NpSG. We describe the identification and structural elucidation of one of the first synthetic cannabinoids not being covered by the NpSG, 5-pentyl-2-(2-phenylpropan-2-yl)-2,5-dihydro-1H-pyrido[4,3-b]indol-1-one. For isolation of the substance a flash chromatography separation was applied. The structure elucidation was performed using gas chromatography-mass spectrometry (GC-MS), gas chromatography-solid state infrared spectroscopy (GC-sIR), liquid chromatography-electrospray ionization-quadrupole time of flight-mass spectrometry (LC-ESI-qToF-MS) and nuclear magnetic resonance (NMR) analysis. Additionally, binding affinity towards the cannabinoid receptors CB1 and CB2 and efficacy in a cAMP accumulation assay were measured, showing full agonistic activity and high potency at both receptors. The new compound bears a γ-carboline core structure circumventing the German NpSG and the generic definitions in other national laws. As a semi-systematic name for 2-cumyl-5-pentyl-gamma-carbolin-1-one CUMYL-PEGACLONE is suggested.

Verification of propofol sulfate as a further human propofol metabolite using LC-ESI-QQQ-MS and LC-ESI-QTOF-MS analysis.

Propofol (2,6-diisopropylphenol) is a water-insoluble, intravenous anesthetic that is widely used for the induction and maintenance of anesthesia as well as for endoscopic and pediatric sedation. After admission, propofol undergoes extensive hepatic and extrahepatic metabolism, including direct conjugation to propofol glucuronide and hydroxylation to 2,6-diisopropyl-1,4-quinol. The latter substance subsequently undergoes phase II metabolism, resulting in the formation of further metabolites (1quinolglucuronide, 4quinolglucuronide and 4quinol-sulfate). Further minor phase I propofol metabolites (2-(ω-propanol)-6-isopropylphenol and 2-(ω-propanol)-6-isopropyl-1,4-quinol)) are also described. Due to its chemical structure with the phenolic hydroxyl group, propofol is also an appropriate substrate for sulfation by sulfotransferases. The existence of propofol sulfate was investigated by liquid chromatography electrospray ionization triple quadrupole mass spectrometry (LCESIQQQ-MS) and liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (LCESI-QTOF-MS). A propofol sulfate reference standard was used for identification and method development, yielding a precursor at m/z 257 (deprotonated propofol sulfate) and product ions at m/z 177 (deprotonated propofol) and m/z 80 ([SO3]-). Propofol sulfate - a further phase II metabolite of propofol - was verified in urine samples by LC-ESI-QQQ-MS and LC-ESI-QTOF-MS. Analyses of urine samples from five volunteers collected before and after propofol-induced sedation verified the presence of propofol sulfate in urine following propofol administration, whereas ascertained concentrations of this metabolite were significantly lower compared with detected propofol glucuronide concentrations. The existence of propofol sulfate as a further phase II propofol metabolite in humans could be verified by two different detection techniques (LCESIQQQ-MS and LC-ESI-QTOFMS) on the basis of a propofol sulfate reference standard. Evaluation of the quantitative analyses of propofol sulfate imply that propofol sulfate represents a minor metabolite of propofol and is only slightly involved in human propofol clearance.

Comparison of antioxidant, antimicrobial activities and chemical profiles of three coffee (Coffea arabica L.) pulp aqueous extracts

BackgroundThis study explored the bioactivities and nutrient compositions of coffee (Coffea Arabica L.) pulp which was prepared in three different ways [Coffee Pulp Extracts (CPE) 1–3]. MethodsThe coffee pulp was prepared in three different ways by distinct selecting and freezing processes. The nutritional values, polyphenol contents, antioxidant activity, and antibacterial properties of the coffee pulp as well as the characterization of the active ingredients by liquid chromatography-electrospray ionization-quadrupole-time-of-flight mass spectrometry (LC-ESI-Q-TOF-MS) were evaluated. ResultsThe chemical profiles of three aqueous extracts were compared and characterized using LC-ESI-QTOF-MS. They showed slightly different nutrient compositions. The total phenolic content was highest in CPE1, and decreased in the following order: CPE1>CPE2 > CPE3. Among the CPEs tested, CPE1 showed the most potent antioxidant activity with IC50 18μg/mL and 82μg/mL by 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) and 1,1-diphenyl-2-picryl-hydrazyl assay, respectively. Chlorogenic acid and caffeine were the most prominent in CPE1 and it contained more compounds than the others. Moreover, CPE1 demonstrated antibacterial activity against both gram-positive (Staphylococcus aureus and Staphylococcus epidermidis) and gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli). ConclusionThese findings indicated that CPE1 has powerful nutrients with antioxidant and antibacterial properties—the potency of which is impacted by the preparation process.

Rapid screening and determination of 11 new psychoactive substances by direct analysis in real time mass spectrometry and liquid chromatography/quadrupole time-of-flight mass spectrometry.

With the amounts and types of new psychoactive substances (NPSs) increasing rapidly in recent years, an excellent high-throughput method for the analysis of these compounds is urgently needed. In this article, a rapid screening method and a quantitative analysis method for 11 NPSs are described and compared, respectively. A simple direct analysis in real time mass spectrometry (DART-MS) method was developed for the analysis of 11 NPSs including three categories of these substances present on the global market such as four cathinones, one phenylethylamine, and six synthetic cannabinoids. In order to analyze these compounds quantitatively with better accuracy and sensitivity, another rapid analytical method with a low limit of detection (LOD) was also developed using liquid chromatography/electrospray ionization quadrupole time-of-flight mass spectrometry (LC/QTOFMS). The 11 NPSs could be determined within 0.5min by DART-MS. Furthermore, they could also be separated and determined within 5min by the LC/QTOFMS method. The two methods both showed good linearity with correlation coefficients (r(2) ) higher than 0.99. The LODs for all these target NPSs by DART-MS and LC/QTOFMS ranged from 5 to 40ngmL(-1) and 0.1 to 1ngmL(-1) , respectively. Confiscated samples, named as "music vanilla" and "bath salt", and 11 spiked samples were firstly screened by DART-MS and then determined by LC/QTOFMS. The identification of NPSs in confiscated materials was successfully achieved, and the proposed analytical methodology could offer rapid screening and accurate analysis results. Copyright © 2016 John Wiley & Sons, Ltd.

Determination of peptide and protein diversity in venom of the spider Selenocosmia jiafu by high performance liquid chromatography and mass spectrometry

Selenocosmia jiafu (S. jiafu) is recently identified as a new species of spider in P. R. China. These medium bodied venomous spiders are distributed mainly in the hilly areas of southwest of China, mostly at Yunnan and Guangxi Provinces. In order to understand the composition of the S. jiafu venom, we performed a preliminary analysis of this venom using reversed-phase high performance liquid chromatography (RP-HPLC), matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The S. jiafu venom was separated by RP-HPLC in an analytical C18 column (phenomenex 100 A, 250 mm x 4.6 mm, 5 µm) equilibrated with solution A (distilled water with 0.1% trifluoroacetic acid), using a gradient from 0% to 50% of solution B (acetonitrile with 0.1% trifluoroacetic acid) over 50 min with a flow rate of 1 mL/min. The isolated venom proteins were treated with in-gel digestion separated by SDS- PAGE and then identified by liquid chromatography-electrospray ionization quadrupole-time of flight mass spectrometry (LC-ESI-QTOF-MS) techniques. The results show that more than 40 fractions eluted were monitored at 215 nm in the RP-HPLC chromatogram of the venom of the spider S. jiafu. Most of the fractions were eluted with retention times of 5-15 min and 25-40 min, corresponding to 5%-15% and 25%-40% acetonitrile, respectively. The venom contains 238 peptides that follow a bimodal distribution, with about 62.5% of the peptides having a relative molecular mass of 3,000-4,500 and about 33.2% of the peptides having a relative molecular mass of 1,000-3,000. This distribution model is rather different from those of peptides from other tarantula spider venoms analyzed. To explore the relative molecular mass distribution of the venom proteins, the venom was analyzed by SDS-PAGE using standard protocols. Except for peptides with relative molecular mass lower than 10,000, the SDS-PAGE electrophoresis revealed three more obvious bands around 50, 72 and 90 kD respectively. Further MS analysis indicated that there are mainly hemocyanin, potassium ion channel protein, calcium protease and so on. Altogether, this study not only indicated there are many peptides and proteins in the S. jiafu venom, but also provided a basis for further case-by-case investigation of peptide toxins from this venom.

Purification and characterization of a novel tetradecapeptide from ginseng polypeptides with enhancing memory activity for mice

Aiming at isolating and investigating the active ingredients of the aqueous extract from Panax ginseng which showed enhancing memory activity, the authors characterized one ingredient. To separate the oligosaccharides and polypeptides, a DEAE-Sephadex A-50 colum was used. The enhanced memory activity in mice was studied by Mirros water maze tesk in mice. The dose of oligosacchrides, polypeptides or Piracetam was 30 mg/kg per day with intraperitoneal administration. The oligosaccharides did not show enhancing memory effect, but polypeptides did show. This result demonstrates that the active ingredients of the aqueous extract from Panax ginseng which showed enhancing memory effect was polypeptides. The purification of the polypeptides was performed on a Sephadex G-25 column. A novel tetradecapeptide was purified from the polypeptides and its structure was determined by liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry(LC-ESI-Q-TOF-MS) with the amino acid sequence of Lys-Ser-Leu-Thr-Leu-Thr-Ser-Ser-Leu-Ser-Tyr-Thr-Asp-Ser.