Detection and identification of plasma progesterone metabolites in the female Florida manatee (Trichechus manatus latirostris) using GC/MS/MS

Florida manatees (Trichechus manatus latirostris) have relatively low peripheral concentrations of progesterone (P4). The objective of this study was to determine if these relatively low P4 concentrations are associated with a high ratio of progestin metabolites and to document metabolite concentrations from individual blood samples obtained from manatees during diestrus or pregnancy. Metabolites known to exist in elephants—terrestrial manatee relatives—were targeted. These included 5α-reduced progestins (5α-pregnane-3,20-dione [5α-DHP] and 3α-hydroxy-5α-pregnan-20-one [5α-P3-OH]) and 17α-hydroxyprogesterone (17α-OHP), which occurs in Asian elephants. An additional, inactive metabolite, 20α-hydroxyprogesterone (20α-OHP), indicative of P4 overproduction, was also targeted. Progesterone itself was the predominant progestin detected in pregnant and nonpregnant manatee plasma (n = 10) using gas chromatography-mass spectrometry with tandem quadrupole detectors (GC/MS/MS). Progesterone concentrations in pregnant females varied from early (moderate to high) through mid and late (low) pregnancy. Progesterone concentrations ranged from low to high in nonpregnant, nonlactating females. The most commonly detected metabolite was 5α-P3-OH (n = 7), which occurred in pregnant (lower limit of detection [LLOD] to high) and nonpregnant (trace to high) females. The 5α-DHP metabolite was also detected in pregnant (LLOD to moderate) and nonpregnant (low) females. The 17α-OHP metabolite was not detected in any tested female. The 20α-OHP metabolite was detected in one nonpregnant, nonlactating, captive female (LLOD). Metabolites were most prevalent during early pregnancy, concurrent with maximum P4 concentrations. Based on their concentrations in peripheral circulation, we inferred that these metabolites may have, opposite to elephants, a limited physiologic role during luteal, pregnant, and nonpregnant phases in the manatee.     

Validated GC/MS method for the simultaneous determination of clozapine and norclozapine in human plasma. Application in psychiatric patients under clozapine treatment

A sensitive and specific GC/MS method for the determination of clozapine (CLZ) and its major metabolite norclozapine (NCLZ), in plasma has been developed, optimized and validated. Specimen preparation includes solid-phase extraction of both analytes using Bond-Elut Certify cartridge and further derivatization with TFAA. Clozapine-d8 was used as internal standard for the determination of CLZ and NCLZ. Limits of detection were 0.45 ng/mL for CLZ and 1.59 ng/mL for NCLZ, while limits of quantification were 1.37 ng/mL for CLZ and 4.8 ng/mL for NCLZ, as calculated by the calibration curves. The calibration curves were linear up to 600 ng/mL for CLZ and NCLZ. Absolute recovery ranged from 82.22% to 95.35% for both analytes. Intra- and interday accuracy was less than 7.13% and −12.52%, respectively, while intra- and interday precision was between 9.47% and 12.07%, respectively, for CLZ and NCLZ. The method covers all therapeutic range and proved suitable for the determination of CLZ and NCLZ not only in psychiatric patients but also in forensic cases with clozapine implication.     

除臭大蒜口服液的GC／MS分析

应用GC/MS联用技术,对除臭大蒜口服液进行了检测,定性鉴定了25种含硫有机化合物。二烯丙基硫醚、甲基烯丙基三硫醚、3-乙烯基-1,2-二硫杂-5-环己烯、2-乙烯基-1,3-二硫杂-5-环己烯和二烯丙基三硫醚是主要组分;二烯丙基四硫醚、烯丙基四硫化氢、2-和3-(2’,3’-二硫杂-5’-己烯基)-3,4-二氢-2H-噻喃、2-(2’-[3’,4’-二氢-2H噻喃基])-1,3-二硫杂-5-环己烯和3-(2’-[3’,4’-二氢-2H-噻喃基])-1,2-二硫杂-5-环己烯是次要组分。最后4种次要组分在大蒜油和大蒜口服液中的鉴定在国内尚属首次。     

新疆有毒植物骆驼蓬挥发油的化学成分测定

目的:研究骆驼蓬挥发油的化学成分.方法:利用水蒸气蒸馏法提取了新疆骆驼蓬挥发油,测的含量为0.04%.采用GC/MS技术对骆驼蓬的挥发油成分进行分离鉴定.结果:分离出18种成分确认其中17种成分.用峰面积归一化法确定了各成分的相对含量,其中主要成分为四氯乙烯(29.87%)、十二烷(16.44%)、十一烷(12.34%)、二(2-甲基丙基)邻苯二甲酸酯(9.09%)、1,3-二甲苯(7.57%)、乙苯(5.84%)1,2-二甲苯(2.81%).结论:四氯乙烯含量最高,通过分析评价为开发骆驼蓬农药提供科学依据.     

GC/MS and LC/MS Phytochemical Analysis of Vigna unguiculata L. Walp Pod

Vigna unguiculata (L. Walp) or Cowpea pod methanolic extracts phytochemical analysis, total phenolic content (TPC), and secondary metabolite profiling were determined using gas chromatography-mass spectrometry (GC/MS) and liquid chromatography-mass spectrometry (LC/MS) analysis. GC/MS analysis revealed twenty compounds in the extract, while LC/MS analysis identified twenty-four compounds. GC/MS chromatogram analysis suggested the presence of opioid α-N-Normethadol a major constituent found in methanolic extract and fatty acid esters carotenoid is found second major constituent. LC/MS chromatogram and the mass spectral analysis demonstrated the presence of flavonoids, carotenoids, and alkaloids as major phytochemicals. We investigated the antibacterial, anti-fungal, and anti-oxidant activity of pod methanolic extract. The extract was found equally effective against E. coli, S. pyogenes, and P. aeruginosa with MIC 100 μg/mL similar to the standard Ampicillin (MIC 100 μg/mL). C. albicans were found to be most susceptible to Vign unguiculata pods methanolic extract with a MIC of 250 μg/mL. The pod extract showed significant DPPH scavenging activity (IC₅₀=78.38±0.15) which suggests its antioxidant potential.     

鸡尾木叶脂溶性挥发物化学成分的GC/MS分析

采用气相色谱-质谱联用仪对鸡尾木枝叶脂溶性挥发物成分进行分析,共分离出51个组分,经检索鉴定了其中31个,其含量占挥发物总量的89%。主要化学成分为香橙烯、维生素E、亚油酸、β-岩藻甾醇等,并首次发现该植物中含有异硫氰酸苄酯。     

南五味子脂溶性成分的GC-MS分析

目的:对南五味子脂溶性成分进行研究。方法:采用索氏提取法提取脂溶性成分,甲酯化后用GC-MS联用技术分离鉴定其组成和含量。结果:脂溶性成分的得率为15．42％。鉴定了32个化合物,占样品总量的91．95％,其中脂肪酸成分的量占81．30％。含量较高的化合物为亚油酸(57．63％),油酸(13．37％),棕榈酸(7．16％)。结论:首次对南五味子脂溶性成分进行了分析,主要为脂肪酸,不饱和脂肪酸占优势。     

湖北栀子花挥发油的GC/MS分析

利用水蒸气蒸馏法从湖北栀子花鲜花中提取栀花挥发油。通过ＤＢ－５弹性石英毛细管柱ＧＣ／ＭＳ分析所得栀子花挥发油,共鉴定了４０个化合物并测定了其相对含量。湖北子发挥发油的主要成分为芳樟醇（１７．９２％）,茉莉内酯（９．１１％）和惕各酸顺－３－己烯酯（６．５４％）。     

Dopamine in tissues of the hydrozoan jellyfishPolyorchis penicillatus as revealed by HPLC and GC/MS

Summary High performance liquid chromatography of alumina extracts of several tissues inPolyorchis penicillatus show the presence of dopamine and a catecholamine resembling norepinephrine. Dopamine is found in the highest concentrations in nerve-rich tissue (120 fmol·mg wet wt^–1), at intermediate concentrations in endoderm-rich tissue (30 fmol·mg^–1), and at the lowest concentrations in the mesoglea (10 fmol·mg^–1). The presence of dopamine was confirmed using gas chromatography/mass spectrometry with negative ion chemical ionization, but norepinephrine and epinephrine could not be detected in nerve-rich tissue.     

GC/MS analysis of the plant hormones in seeds of Cucurbita maxima

The GC/MS detection is reported of over 30 compounds, in extracts of the endosperm and embryos from seeds of Cucurbita maxima. The compounds which were identified from reference spectra include: cis,trans-ABA; trans,trans-ABA; dihydrophaseic acid; IAA; GA₄; GA₁₂; GA₁₃; GA₂₅; GA₃₉; GA₄₃; GA₄₉; ent-13-hydroxy-, ent-6α,7α-and ent-7α,13-dihydroxy-, and ent-6α,7α,13-trihydroxykaur-16-en-19-oic acids; ent-7α,16,17-trihydroxy- and ent-6α,7α,16,17-tetrahydroxy-kauran-19-oic acids, ent-6,7-seco-7-oxokauren-6,19-dioic acid and/or ent-6,7-secokauren-6,7,19-trioic acid, and 7β,12α-dihydroxykaurenolide. New compounds, the structures of which were deduced from GC/MS data, include: the 12α-hydroxy-derivatives of GA₁₂, GA₁₄, GA₃₇ and GA₄, and the 12β-hydroxy-derivatives of ent-7α-hydroxy- and ent-6α,7α-dihydroxykaurenoic acids.     

Headspace Solid Phase Microextraction Coupled to GC/MS for the Analysis of Volatiles of Honeys from Arid and Mediterranean Areas of Algeria

The volatile composition of seven honey samples collected from various regions of Algeria and feeding on different plants have been determined. The Headspace Solid‐Phase MicroExtraction (HS‐SPME) coupled with Gas Chromatography‐Mass Spectrometry (GC/MS) was used to achieve the purpose. In this work, different parameters of the HS‐SPME analytical method were investigated in order to reach maximal sensitivity, and thus to obtain maximum information about the volatile profile of Algerian honey. These parameters include saline medium, HS extraction temperature, and the nature of the fiber used. The results showed a great diversity in the chemical composition, in total 124 compounds from different chemical classes were identified, including compounds found for the first time in honey. The Ascending Hierarchical Classification (AHC) demonstrated the importance of choosing SPME extraction conditions to find volatile compounds, which could be as specific markers of the floral or geographical origin of honey, the latter was optimized in the parameter PDMS‐55 °C.     

毛细管气相色谱/质谱法测定关苍术中的挥发性成分

采用正己烷萃取关苍术中挥发性成分 ,以GC -MS分离 ,经计算机检索系统处理与质谱标准谱图核对 ,检出香橙烯 ([ ]-Aromadendrene)、反式石竹烯 (trans -Caryophyllene)、γ -榄香烯 (gamma -Elemene)、α -草烯(alpha -Humulene)、β -桉叶烯 (beta-Selinene)、2 -甲基苯酚 (Phenol,2 -methyl- )、石竹二烯酮 (Caryophylla - 2 [12 ],6 [13]-dien - 5 -one)、1-甲氧基 - 2 (1-甲基 - 2 -亚甲基 -环戊基 ) -苯 (Benzene,1-methoxy - 2 [1-methyl- 2 -methylenecyclopentyl]- )、呋喃 - 2 -亚甲基 - (1H -嘌呤 - 6基 ) -胺 (1H -Purin - 6 -ammine,N - [2 -furanylmethyl]- )、白术内酯 (Butenolide)、1-溴 - 8十七炔 (8-Heptadecyne ,1-beome)等 11种挥发性成分     

兰州油松松皮挥发性成分分析

采用水蒸气蒸馏法对兰州产油松松皮的挥发性成分进行提取,采用GC／MS方法分离、鉴定了其中42个化学成分。     

A strategy for modelling dynamic responses in metabolic samples characterized by GC/MS

A multivariate strategy for studying the metabolic response over time in urinary GC/MS data is presented and exemplified by a study of drug-induced liver toxicity in the rat. The strategy includes the generation of representative data through hierarchical multivariate curve resolution (H-MCR), highlighting the importance of obtaining resolved metabolite profiles for quantification and identification of exogenous (drug related) and endogenous compounds (potential biomarkers) and for allowing reliable comparisons of multiple samples through multivariate projections. Batch modelling was used to monitor and characterize the normal (control) metabolic variation over time as well as to map the dynamic response of the drug treated animals in relation to the control. In this way treatment related metabolic responses over time could be detected and classified as being drug related or being potential biomarkers. In summary the proposed strategy uses the relatively high sensitivity and reproducibility of GC/MS in combination with efficient multivariate curve resolution and data analysis to discover individual markers of drug metabolism and drug toxicity. The presented results imply that the strategy can be of great value in drug toxicity studies for classifying metabolic markers in relation to their dynamic responses as well as for biomarker identification.     

珍稀水生动物白暨豚油中脂肪酸的GC／MS分析

白暨豚是一种珍稀水生动物.本文报道了运用 Dexsil-300GC 毛细管柱色质联用仪,对白(?)豚油中脂肪酸进行了分析鉴定,并检测到了22种脂肪酸,其中主要脂肪酸是十四碳烯酸、十六碳烯酸和十八碳烯酸.     

Bioanalytical method for the simultaneous determination of d- and l-serine in human plasma by LC/MS/MS

d-Serine is an endogenous modulator of N-methyl-d-aspartate (NMDA) receptors. Plasma concentrations of d-serine and the ratio of d-serine to total serine may be used as clinically-translatable biomarkers in NMDA receptor-related disease. We developed a highly sensitive and specific method using high performance liquid chromatography tandem mass spectrometry (LC/MS/MS) for the simultaneous determination of the d- and l-isomers of serine in human plasma. Since d- and l-serine are endogenous components, phosphate buffered saline was used as the surrogate matrix. d- and l-serine in human plasma and PBS were treated by cationic exchange solid phase extraction. d-Serine (m/z 106.1 > 60.0), l-serine (m/z 106.1 > 60.1) and dl-serine-d₃ (m/z 109.1 > 63.0) were detected using a multiple reaction monitoring. The enantiomer separation of d- and l-serine was successfully achieved without any derivatization step using tandemly-arranged and ice-cold CROWNPAK CR-I(+) columns with an isocratic mobile phase comprised of 0.3% trifluoroacetic acid in 10% acetonitrile. The standard curves were linear throughout the calibration range with 0.01–10 μg/mL (d-serine) and 0.1–100 μg/mL (l-serine), respectively. Intra-day and inter-day precision and accuracy of the quality control samples were within relative standard deviations of less than 15%. The endogenous concentrations of d- and l-serine in human plasma were 0.124–0.199 and 7.97–13.1 μg/mL, respectively.     

气相色谱/质谱法研究栀子花头香成分

The floral volatiles of Gardenia jasminodes vat. grandiflora were investigated by adsorption wire/GC/MS. As a result 86 compounds were separated and determined, which amount to 98.5% of the total volatiles. The main compounds were linalool, β-myrcene, methyl benzoate, L-limonene, ocimene, cis-3-hexenyl tiglate, cis-3-hexenylisovalerate, iso-amyltiglate, etc.     

工业生产ABA发酵液中脂溶性成分的GC/MS分析

利用气相色谱质谱联用技术,首次对工业生产脱落酸的发酵液中脂溶性成分进行分析,经气相色谱分离出了55个峰,共鉴定了其中的36种化学成分,占总成分的72.80%。分析鉴定结果表明,发酵液的脂溶性成分中主要化学成分为饱和烃类,如十四碳烷至三十一碳烷,占总脂溶性成分的27.49%;其次是脂肪酸酯,如十五碳酸乙酯、棕榈酸乙酯、油酸乙酯与亚油酸乙酯等,占总脂溶性成分的19.02%。