Enantioselective analysis of venlafaxine and its active metabolites: A review on the separation methodologies.

Venlafaxine (VFX) is a serotonin and norepinephrine reuptake inhibitor chiral drug used in therapy as an antidepressant in the form of a racemate consisting of R- and S-VFX. The two enantiomers of VFX exhibit different pharmacological activities: R-VFX inhibits both norepinephrine and serotonin synaptic reuptake, whereas S-VFX inhibits only the serotonin one. R- and S-VFX are metabolized in the liver to the respective R- and S-O-desmethylvenlafaxine (ODVFX), R- and S-N-desmethylvenlafaxine (NDVFX), and R- and S-N,O-didesmethylvenlafaxine (NODVFX). The pharmacological profile of ODVFX is close to that of VFX, whereas the other two chiral metabolites (NDVFX and NODVFX) have lower affinity for the receptor sites. The pharmacokinetics of the VFX enantiomers appear stereoselective, including the metabolism process. In the past 20 years, several studies describing the enantioselective analysis of R- and S-VFX in pharmaceutical formulations and its chiral metabolites in biological matrices were published. These methods encompass liquid chromatography coupled with UV detection, mass spectrometry, or tandem mass spectrometry, and capillary electrophoresis. This paper reviews the published methods used for the determination of the individual enantiomers of VFX and its chiral metabolites in different matrices.

Identification and distribution of mycosporine-like amino acids in Brazilian cyanobacteria using ultrahigh-performance liquid chromatography with diode array detection coupled to quadrupole time-of-flight mass spectrometry.

RATIONALE: Mycosporine-like amino acids (MAAs) are UV-absorbing compounds produced by fungi, algae, lichens, and cyanobacteria when exposed to UV radiation. These compounds have photoprotective and antioxidant functions and have been widely studied for possible use in sunscreens and anti-aging products. This study aims to identify MAA-producing cyanobacteria with potential application in cosmetics. METHODS: A method for the identification of MAAs was developed using ultrahigh-performance liquid chromatography with diode array detection coupled to quadrupole time-of-flight mass spectrometry (UHPLC-DAD/QTOFMS). Chromatographic separation was carried out using a Synergi 4 µ Hydro-RP 80A column (150 × 2,0 mm) at 30°C with 0.1% formic acid aqueous solution + 2 mM ammonium formate and acetonitrile/water (8:2) + 0.1% formic acid as a mobile phase. RESULTS: Out of the 69 cyanobacteria studied, 26 strains (37%) synthesized MAAs. Nine different MAAs were identified using UHPLC-DAD/QTOFMS. Iminomycosporines were the major group detected (7 in 9 MAAs). In terms of abundance, the most representative genera for MAA production were heterocyte-forming groups. Oscilatoria sp. CMMA 1600, of homocyte type, produced the greatest diversity of MAAs. CONCLUSIONS: The UHPLC-DAD/QTOFMS method is a powerful tool for identification and screening of MAAs in cyanobacterial strains as well as in other organisms such as dinoflagellates, macroalgae, and microalgae. The different cyanobacterial genera isolated from diverse Brazilian biomes and environments are prolific sources of MAAs.

Dynamic changes in norisoprenoids and phenylalanine-derived volatiles in off-vine Vidal blanc grape during late harvest.

We investigated the dynamic changes in norisoprenoids and phenylalanine derivatives in off-vine Vidal blanc. Glycosidically bound as well as free-form volatile compounds were identified by GC-MS in two vintages. Thus, off-vine grape exhibited the development of four higher alcohols (viz. linalool oxide, 2-octanol, 1-pentanol, and 1-heptanol), C13-norisoprenoids (α-ionone), phenylalanine-derivates (2-phenylethanol), whereas ß-ionone and geranial showed high correlation in on-vine grape. Freeze-thaw cycles and desiccation, two exterior stress affect volatile compound development, resulted in content fluctuations during late harvest. Interestingly, the total content of higher alcohols was higher in on-vine grapes than off-vine grapes in two vintages respectively. Interestingly, the content of higher alcohols was higher in off-vine samples in the 2016 and 2017 vintages. In terms of physicochemical parameters, off-vine Vidal showed results similar to those of on-vine sample. Nevertheless, sensorial impression of the grape juice was influenced by interaction of vintages and vine treatments.

Aroma characterization of Hanzhong black tea (Camellia sinensis) using solid phase extraction coupled with gas chromatography-mass spectrometry and olfactometry and sensory analysis.

The unique aroma of the Hanzhong black tea is due to the special location of the harvesting place and specific manufacturing processes. In this study, a solid phase extraction method (SPE) as sample preparation tool was combined with gas chromatography (GC) as separation technique and several detection systems such as mass spectrometry (MS), flame ionization (FID) and olfactometry (O), which, together with sensorial analysis were used to characterize aroma compounds in Hanzhong black tea infusion. Seventy three aroma compounds were identified and quantified in the tea infusion by the GC-MS and GC-FID methods, respectively. Among them, odor perceptions of 24 compounds were characterized by the GC-O analysis. It was found that linalool oxide I, II and III, E,E-2,4-nonadienal, 4,5-dimethyl-3-hydroxy-2,5-dihydrofuran-2-one, 1-octen-3-one, E,Z-2,6-nonadienal, bis(2-methyl-3-furyl) disulfide had higher odor activity value in the tea infusion and offered floral, fatty, and caramel, mushroom, cucumber, and cooked beef -like odors, respectively. Overall, floral and mushroom and caramel -like odors significantly dominated in the Hanzhong black tea infusion.

Anti-inflammatory and anti-edematogenic action of the Croton campestris A. St.-Hil (Euphorbiaceae) essential oil and the compound ß-caryophyllene in in vivo models.

BACKGROUND: Inflammation makes up a set of vascularized tissue reactions acting in the defense of the body against harmful stimuli. Natural products are a lower cost alternative with better benefit, often used in popular medicine in the treatment of inflammatory processes. Several species from the genus Croton have scientifically proven anti-inflammatory action. PURPOSE: This study aims to analyze the chemical composition of the Croton campestris A. St.-Hil essential oil (EOCC), derived from fresh leaves, as well as to evaluate the anti-inflammatory potential and the possible mechanisms of action of the EOCC and its constituent ß-caryophyllene. METHODS: The assays were performed in in vivo models of acute and chronic inflammation. Initially, the chemical composition of the EOCC was determined and its oral toxicity was evaluated, followed by the evaluation of its topical antiedematogenic effect through acute and chronic ear edema induced by Croton oil. For the systemic verification of an anti-inflammatory action, the abdominal contortions, formalin test, paw edema induced by carrageenan, dextran, histamine and arachidonic acid models, as well as a peritonitis test, vascular permeability and granuloma assays were performed. RESULTS: The evaluation of the essential oil chemical composition revealed the presence of ß-caryophyllene (15.91%), 1,8-cineol (16.98%) and germacrene-D (14.51%) as its main constituents. The EOCC had no relevant clinical toxicity on oral administration, with an LD50 of more than 5000 mg/kg. The tested substances showed anti-inflammatory action in the abdominal contortions, paw edema induced by carrageenan, dextran, histamine and arachidonic acid models, the formalin test, peritonitis test and vascular permeability; however, ß-caryophyllene had no significant effect on the granuloma assay. This suggests as a hypothesis that both substances tested showed significant influence on the arachidonic acid and histamine pathway reducing edema in these models. CONCLUSION: The tested substances have a clinically safe profile, additionally the EOCC and ß-caryophyllene presented relevant anti-inflammatory activity. This study supports the hypothesis that ß-caryophyllene, in association with other constituents present in the EOCC such as 1,8-cineole, contributed to the anti-inflammatory effect observed, in addition to suggesting that one of the mechanisms of action probably involves the inhibition of cytokines with the involvement of the arachidonic acid and histamine pathways.

Chemometric analysis of NMR and GC datasets for chemotype characterization of essential oils from different species of Ocimum.

The genus Ocimum (Labiatae) comprises 30 species found in tropical and subtropical regions of the planet, of which species O. basilicum L. and O. gratissimum are widely used in food and traditional medicine. Phytochemical studies on Ocimum have revealed a number of essential oil chemotypes, for example, eugenol, methyl chavicol, linalool, and methyl cinnamate. Since essential oils are commercially assessed according to their content, the aim of this study was to develop a simple and precise method for their qualitative and quantitative analysis using NMR spectroscopy combined with chemometrics. Seven essential oils from different species of Ocimum, an unknown sample, and a commercial sample were evaluated and the results compared to those from established and precise GC-MS and GC-FID methods. Chemometric evaluation from both 1H NMR and GC-MS data revealed three chemotypes: eugenol for O. gratissimum, O. micranthum, and O. tenuiflorum; estragole for O. basilicum, O. basilicum var. purpuracens, and O. selloi; and methyl cinnamate for O. americanum. The unknown and commercial species were classified as cinnamate and eugenol chemotypes, respectively. Despite the corroborating results, the chemometric analysis revealed the higher robustness (better adjustment) of the 1H NMR model compared to the GC-MS method in terms of certain statistical parameters. The 1H NMR method allows for the detection and quantification of organic compounds in a complex mixture without the need for certified standard compounds. Although GC-MS and GC-FID were able to detect five compounds not observed by NMR spectroscopy, the four most important metabolites (eugenol, estragole, methyl cinnamate, and eucalyptol) were more readily detected and quantified by 1H NMR.

Foliar Terpene Chemotypes and Herbivory Determine Variation in Plant Volatile Emissions.

Plants that synthesize and store terpenes in specialized cells accumulate large concentrations of these compounds while avoiding autotoxicity. Stored terpenes may influence the quantity and profile of volatile compounds that are emitted into the environment and the subsequent role of those volatiles in mediating the activity of herbivores. The Australian medicinal tea tree, Melaleuca alternifolia, occurs as several distinct terpene chemotypes. We studied the profile of its terpene emissions to understand how variations in stored foliar terpenes influenced emissions, both constitutive and when damaged either by herbivores or mechanically. We found that foliar chemistry influenced differences in the composition of terpene emissions, but those emissions were minimal in intact plants. When plants were damaged by herbivores or mechanically, the emissions were greatly increased and the composition corresponded to the constitutive terpenes and the volatility of each compound, suggesting the main origin of emissions is the stored terpenes and not de novo biosynthesized volatiles. However, herbivores modified the composition of the volatile emissions in only one chemotype, probably due to the oxidative metabolism of 1,8-cineole by the beetles. We also tested whether the foliar terpene blend acted as an attractant for the specialized leaf beetles Paropsisterna tigrina and Faex sp. and a parasitoid fly, Anagonia zentae. None of these species responded to extracts of young leaves in an olfactometer, so we found no evidence that these species use plant odor cues for host location in laboratory conditions.

Resistance to Hydrogen Peroxide Highlights Gymnodinium catenatum (Dinophyceae) Sensitivity to Geomagnetic Activity.

The chain-forming dinoflagellate Gymnodinium catenatum was exposed to hydrogen peroxide. Microscopical examination revealed striking dose-response alterations in chain formation above 245 µm: singlets replaced the dominance of long chain formations. These observations were valid for cells acclimated to halogen light. Under fluorescent light, cells were more resistant to modifications in chain length after H2 O2 exposure. Growth along 9 h in the presence of extracellular H2 O2 followed an hormesis response in both light regimes. Under halogen light conditions, alterations in chain formation and net growth were related to culture time, inocula concentration and geomagnetic activity (GMA) in the proceeding hours. Below a 16 nT threshold in GMA average growth was 0%, while above 16 nT it was circa +9%, independently if the local static magnetic field was altered by a permanent magnet or not. Mycosporine-like amino acids that can have an antioxidant role and are easily oxidized decreased from 7.1 to 6.5 pg cell-1 (P < 0.05) under halogen light and exposure to 245 µm H2 O2 . GMA, as well as UV-A, increased stress responsiveness that can momentarily protect cells from extracellular H2 O2 addition. However, stress response is dependent on bio-availability of several micronutrients and macronutrients, many found at limiting concentrations in oceanic waters.

Phytochemical components, total phenol and mineral contents and antioxidant activity of six major medicinal plants from Rayen, Iran.

The aim of this work was to evaluate the phytochemical components, minerals, the antioxidant activity and total phenol contents of the essential oil from aerial parts of six major medicinal plants in Rayen, Iran. The plants included Ranunculus arvensis, Teucrium polium, Dracocephalum polychaetum, Kelussia odoratissima, Artemisia sieberi and Thymus kotschyanus. Total phenol content ranged from 0.03 to 0.158 mg/mL. A. sieberi showed the highest radical scavenging ability (IC50 = 94 µg/mL). The amount of minerals ranged as follows: P (0.23-29%), K (1.08-4.76%), Ca (0.78-2.35%), Mg (0.24-0.94%), Cu (8.3-15 mg/kg), Cd (0.7-1.1 mg/kg), Pb (2-11.7 mg/kg) and Fe (250-1280 mg/kg). A total of 79 compounds were identified across all plants. The main components studied in the plants were l-perillaldehyde, biosol, carvacrol, 1,8-cineol, terpinyl acetate and 1,2,3,6,7,7 a-hexahydro-5 h-inden 5-one.

Chemical composition and antimicrobial activity of the essential oil of Mentha mozaffarianii Jamzad growing wild and cultivated in Iran.

The aerial parts of wild and cultivated Mentha mozaffarianii Jamzad were collected at full flowering stage from two provinces (Hormozgan and Fars) of Iran. The essential oils were extracted by a Clevenger approach and analysed using GC and GC-MS. The main components in wild plants were piperitenone (33.85%), piperitone (21.18%), linalool (6.89%), pulegone (5.93%), 1, 8.cineole (5.49%), piperitenone oxide (5.17%) and menthone (4.69%) and in cultivated plants, cis-piperitone epoxide (28.89%), linalool (15.36%), piperitone (11.57%), piperitenone oxide (10.14%), piperitenone (8.42%),1,8-cineole (3.60%) were the main constituents in essential oil. The in vitro antimicrobial activity of the essential oil of M. mozaffarianii was studied against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Candida albicans. The results of the bioassays showed that the oil exhibited high antimicrobial activity against all the tested pathogens.

Attraction behaviour of Anagrus nilaparvatae to remote lemongrass (Cymbopogon distans) oil and its volatile compounds.

Utilisation of Anagrus nilaparvatae is a promising and effective method for planthoppers manipulation. Twenty-seven components of remote lemongrass (Cymbopogon distans) oil were identified by GC/MS and nine volatiles were selected for behavioural experiments. In this study, we noted that the remote lemongrass oil was attractive to female A. nilaparvatae at concentrations of 0.1 and 1 mg/L. α-Pinene, ß-pinene, eucalyptol, carveol and D-carvone attracted female wasps in the dose-dependent bioassays. Blend 1 (a mixture of eucalyptol, D-carvone, carveol, α-pinene, and ß-pinene with ratios of remote lemongrass oil volatiles of 625:80:11:5:3) attracted female wasps at 10 mg/L, while blend 2 (a mixture of the same five volatiles at the same loading ratio) attracted them at 0.1 and 1 mg/L. These results suggested that plant essential oils could be attractants for natural enemies to control pests. The ratios of volatiles in the mixtures affect the attractiveness of the synthetic mixtures.

Jasmonic acid changes the composition of essential oil isolated from narrow-leaved lavender propagated in in vitro cultures.

The aim of the present study was to determine the effect of jasmonic acid added to the culture medium on composition of Lavandula angustifolia essential oils. The chemical composition was determined by gas chromatography coupled to mass detector (GC/MS). The experiment was conducted with the use of MS medium supplemented with increasing concentration of JA (0.2, 0.5, 1, 1.5 mg∙dm-3). It was found that the analysed essential oils varied in terms of chemical composition depending on the content of JA in the medium. All obtained essential oils were characterised by a high content of σ-cadinene (17.06-29.64%), borneol (6.66-17.47%), caryophyllene oxide (8.30-14.01%), τ-cadinol (4.87-9.16%), beta-caryophyllene (3.54-6.57%), 1.8-cineole (1.94-5.87%), ß-pinene (1.48-3.05%), geranyl acetate (0.56-2.14%) and myrtenal (0.65-2.14%).

Time frequency analysis of olfactory induced EEG-power change.

OBJECTIVES: The objective of the present study was to investigate the usefulness of time-frequency analysis (TFA) of olfactory-induced EEG change with a low-cost, portable olfactometer in the clinical investigation of smell function. MATERIALS & METHODS: A total of 78 volunteers participated. The study was composed of three parts where olfactory stimuli were presented using a custom-built olfactometer. Part I was designed to optimize the stimulus as well as the recording conditions. In part II EEG-power changes after olfactory/trigeminal stimulation were compared between healthy participants and patients with olfactory impairment. In Part III the test-retest reliability of the method was evaluated in healthy subjects. RESULTS: Part I indicated that the most effective paradigm for stimulus presentation was cued stimulus, with an interstimulus interval of 18-20s at a stimulus duration of 1000ms with each stimulus quality presented 60 times in blocks of 20 stimuli each. In Part II we found that central processing of olfactory stimuli analyzed by TFA differed significantly between healthy controls and patients even when controlling for age. It was possible to reliably distinguish patients with olfactory impairment from healthy individuals at a high degree of accuracy (healthy controls vs anosmic patients: sensitivity 75%; specificity 89%). In addition we could show a good test-retest reliability of TFA of chemosensory induced EEG-power changes in Part III. CONCLUSIONS: Central processing of olfactory stimuli analyzed by TFA reliably distinguishes patients with olfactory impairment from healthy individuals at a high degree of accuracy. Importantly this can be achieved with a simple olfactometer.

Antimicrobial efficacy of Cinnamomum javanicum plant extract against Listeria monocytogenes and its application potential with smoked salmon.

Extracts from medicinal plants have been reported to possess good antimicrobial properties, but a majority of them remain unexplored. This study aimed at identifying a novel plant extract with antimicrobial activity, to validate its efficacy in food model, and to elucidate its composition and antimicrobial mechanism. A total of 125 plant extracts were screened, and Cinnamomum javanicum leaf and stem extract showed potential antimicrobial activity against Listeria monocytogenes (MIC=0.13mg/mL). Total phenolic content of the extract was 78.3mg GAE/g extract and its antioxidant activity was 57.2-326.5mg TE/g extract. When applied on cold smoked salmon, strong strain-dependent antimicrobial effectiveness was observed, with L. monocytogenes LM2 (serotype 4b) and LM8 (serotype 3a) being more resistant compared to SSA81 (serotype 1/2a). High extract concentration (16mg/mL) was needed to inhibit or reduce the growth of L. monocytogenes on smoked salmon, which resulted in surface color change. GC-MS revealed that eucalyptol (25.54 area%) was the most abundant compound in the crude extract. Both crude extract and eucalyptol induced significant membrane damages in treated L. monocytogenes. These results suggest anti-L. monocytogenes activity of C. javanicum plant extract, identified its major volatile components, and elucidated its membrane-damaging antimicrobial mechanisms.

Comparative Study on Volatile Compounds of Alpinia japonica and Elettaria cardamomum.

The volatile compounds obtained from the ether extracts, headspace gases and steam distillates of Alpinia japonica and Elettaria cardamomum were analyzed by GC/MS. Both species were rich sources of naturally rare fenchane-type monoterpenoids, fenchene, fenchone, fenchyl alcohol and its acetate, together with 1,8-cineole. The distributions of volatile sesquiterpenoids were very poor in both species. Chiralities of fenchone in A. japonica and E. cardamomum were 99% of (1S,4R)-(+)-form. Camphor in A. japonica is composed of a mixture of (1R,4R)-(+)-form (94.3%) and (1S,4S)-(-)-form (5.7%). On the other hand, E. cardamomum produced only (1R,4R)-(+)-camphor (99%).

Characterization of Essential Oil Composition in Different Basil Species and Pot Cultures by a GC-MS Method.

Basil (Ocimum L.) species are used as medicinal plants due to their essential oils exhibiting specific biological activity. The present work demonstrated that both the variety and season/conditions of cultivation had a significant effect on (i) the produced amount (extraction yield), (ii) qualitative, as well as (iii) quantitative profile of basil essential oil. Among studied basil varieties, a new variety, 'Mánes', was characterized for the first time. Based on our quantitative evaluation of GC-MS profiles, the following chemotypes and average concentrations of a main component were detected in the studied basil varieties: 'Ohre', 'Lettuce Leaf', 'Purple Opaal', 'Dark Green' (linalool, 5.99, 2.49, 2.34, 2.01 mg/mL, respectively), and 'Mammolo Genovese', 'Mánes', 'Red Rubin' (eucalyptol, 1.34, 0.96, 0.76 mg/mL, respectively). At the same time, when considering other compounds identified in GC-MS profiles, all the studied varieties, except from 'Lettuce Leaf', were methyl eugenol-rich with a strong dependence of the eugenol:methyl eugenol ratio on the seasonal changes (mainly solar irradiation, but also temperature and relative humidity). More complex and/or variable (depending on the season and cultivation) chemotypes were observed with 'Lettuce Leaf' (plus estragole, 2.27 mg/mL), 'Dark Green' (plus eucalyptol, 1.36 mg/mL), 'Mammolo Genovese' (plus eugenol, 1.19 mg/mL), 'Red Rubin' (plus linalool and eugenol, 0.46 and 0.56 mg/mL, respectively), and 'Mánes' (plus linalool and eugenol, 0.58 and 0.40 mg/mL, respectively). When considering superior extraction yield (ca. 17 mL·kg-1, i.e., two to five times higher than other examined varieties) and consistent amounts (yields) of essential oil when comparing inter-seasonal or inter-year data (RSD and inter-year difference in mean yield values ˂2.5%), this new basil variety is very promising for use in the pharmaceutical, food, and cosmetic industries.

Chemical Compositions and Antioxidant Activities of Essential Oils Extracted from the Petals of Three Wild Tree Peony Species and Eleven Cultivars.

The aim of this study was to investigate the essential oil (EO) compositions and antioxidant activities from petals of three wild tree peony species (Paeonia delavayi, P. lutea, and P. rockii) and eleven P. suffruticosa cultivars from different cultivar groups. The EOs yields varied from 0.63% to 1.25% (v/v) among samples when using supercritical CO2 extraction. One hundred and sixty-three components were detected by GC/MS; and among them, linalool oxide, (Z)-5-dodecen-1-yl acetate, nonadecane, (Z)-5-nonadecene, heneicosane, phytol, and linoleic acid ethyl ester were dominant. According to hierarchical cluster analysis, principal component analysis and correspondence analysis, P. lutea, P. delavayi, and 'High Noon' were clustered in a group described as having a refreshing herbal-like note due to high rates of phytol and linalool oxide. Notably, P. lutea and P. delavayi also had strong DPPH and ABTS radical scavenging activities. These results suggest that P. lutea and P. delavayi are the most promising candidates as useful sources of fragrances and natural antioxidants.

Salvia officinalis L. Essential Oils from Spain: Determination of Composition, Antioxidant Capacity, Antienzymatic, and Antimicrobial Bioactivities.

Four essential oils (EOs) from Salvia officinalis L. cultivated in Spain (Murcia Province) were analyzed by gas chromatography coupled with mass spectrometry (GC/MS) to determine their relative and absolute compositions. The main components were α-thujone (22.8 - 41.7%), camphor (10.7 - 19.8%), 1,8-cineole (4.7 - 15.6%), and ß-thujone (6.1 - 15.6%). Enantioselective gas chromatography identified (-)-α-thujone and (+)-camphor as the main enantiomers in all the analyzed EOs. Furthermore, when the EOs were tested to determine their antioxidant activity against free radicals and as ferric reducing and ferrous chelating agents, all were seen to have moderate activity due to the compounds they contained, such as linalool or terpinene. Because of their known relation with inflammatory illnesses and Alzheimer's disease, respectively, the inhibition of lipoxygenase and acetylcholinesterase was studied using the EOs. Some individual compounds also inhibited these enzymes. In addition, the studied EOs were able to inhibit the growth of Escherichia coli, Staphylococcus aureus, and Candida albicans. The characterization carried out increases our awareness of the possible uses of S. officinalis EO as natural additives in food, cosmetics, and pharmaceuticals.

Phenolic Compounds, Volatiles and Antioxidant Capacity of White Myrtle Berry Liqueurs.

The aim of this research was to evaluate the antioxidant capacity and physical-chemical characteristics of commercial white myrtle berry (Myrtus communis L. var. leucocarpa DC) liqueur (WMBL). The total phenolic (TP) content was measured spectrophotometrically, applying a modified Folin-Ciocalteu's method, and phenolic compounds were identified by high-performance liquid chromatography (HPLC) coupled with electrospray mass spectrometry, and quantified by HPLC coupled with ultraviolet/visible detection. The antioxidant capacities were evaluated by FRAP, CUPRAC, DPPH•, and ABTS•+ assays. The volatiles were assessed by gas chromatography and mass spectrometry (GC-MS/FID) after headspace solid-phase microextraction (HS-SPME) and liquid-liquid extraction (LLE). WMBL showed lower TP levels (636.3 ± 39.2 mg GAE/L) than in purple myrtle berry liqueur (PMBL). Nevertheless, WMBL exhibited better antioxidant capacities, potentially due to high concentrations of gallic acid (294.2 ± 14.2 mg/L) and its derivatives (58.3 ± 2.1 mg/L). Other phenolic compounds detected by HPLC-DAD and LC-MS/MS were flavonols like myricetin and its derivatives (myricetin-3-O-galactoside and myricetin-3-O-rhamnoside) with concentrations similar to those found in PMBL. GC-MS/FID analysis revealed 44 compounds (terpenes, higher aliphatic compounds and shikimic acid pathway derivatives). 1,8-Cineole was the most abundant terpene in the liqueur (26.5% (HS-SPME) and 9.6% (LLE)).

Glass bottle sampling solid phase microextraction gas chromatography mass spectrometry for breath analysis of drug metabolites.

Breath analysis is a non-invasive approach which may be applied to disease diagnosis and pharmacokinetic study. In the case of offline analysis, the exhaled gas needs to be collected and the sampling bag is often used as the storage vessel. However, the sampling bag usually releases some extra compounds, which may interfere with the result of the breath test. In this study, a novel breath sampling glass bottle was developed with a syringe needle sampling port for solid phase microextraction (SPME). Such a glass bottle scarcely liberates compounds and can be used to collect exhaled gas for ensuing analysis by gas chromatography-mass spectrometry (GC-MS). The glass bottle sampling SPME-GC-MS analysis was carried out to investigate the breath metabolites of myrtol, a multicompound drug normally used in the treatment of bronchitis and sinusitis. Four compounds, α-pinene, 2,3-dehydro-1,8-cineole, d-limonene and 1,8-cineole were found in the exhaled breath of all eight volunteers who had taken the myrtol. While for other ten subjects who had not used the myrtol, these compounds were undetectable. In the SPME-GC-MS analysis of the headspace of myrtol, three compounds were detected including α-pinene, d-limonene and 1,8-cineole. Comparing the results of breath and headspace analysis, it indicates that 2,3-dehydro-1,8-cineole in the breath is the metabolite of 1,8-cineole. It is the first time that this metabolite was identified in human breath. The study demonstrates that the glass bottle sampling SPME-GC-MS method is applicable to exhaled gas analysis including breath metabolites investigation of drugs like myrtol.