GC–MS

GC - MS
  • 文章类型: Journal Article
    在加工过程中,在海参粉中检测到40多种挥发性化合物(通过冷冻干燥,海水淡化,超临界流体萃取和超微研磨)通过包括电子鼻在内的多种方法,GC-IMS和GC-MS。已经确定醛是原始冻干样品中的主要挥发性物质,约占总挥发性物质的30%。此外,我们建立了一种超临界流体萃取策略,可以有效地去除海参粉末中的醛。GC-IMS和GC-MS表明醛的相对含量显著降低了14%和28%,分别。使用GC-MS定量醛显示辛醛从927μg/kg显著降低至159μg/kg。进一步的调查结合OAV分析显示,冻干海参粉中的17种挥发性物质被认为是主要的挥发性化合物(OAV>1)。在海参粉末中发现的主要鱼腥味化合物被鉴定为己醛,octanal,和使用GC-O的身份不明的化合物,通过我们建立的超临界流体萃取策略可以有效地去除(OAV无法估计)。
    More than 40 volatile compounds were detected in sea cucumber powder during the processing (through freeze-dried, desalination, supercritical fluid extraction and ultra-micro grinding) by multiple methods including e-nose, GC-IMS and GC-MS. It has been determined that aldehydes are the predominant volatile substances in the original freeze-dried sample, accounting for about 30 % of the total volatile substances. In addition, we established a supercritical fluid extraction strategy that could efficiently remove the aldehydes from the sea cucumber powder. GC-IMS and GC-MS showed that the relative content of aldehydes significantly decreased by 14 % and 28 %, respectively. Quantification of aldehydes using GC-MS showed a significant decrease in octanal from 927 µg/kg to 159 µg/kg. Further investigation combined with OAV analysis showed that 17 volatile substances in the freeze-dried sea cucumber powder were considered to be the predominant volatile compounds (OAV > 1).The primary fishy compounds found in sea cucumber powder were identified as hexanal, octanal, and an unidentified compound using GC-O, which can be effectively removed (OAV can\'t been estimated) by the supercritical fluid extraction strategy we established.
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  • 文章类型: Journal Article
    乳腺癌(BC)仍然是全球女性中最常见的癌症,尽管在预防和治疗方面取得了重大进展。全球BC的发病率不断上升,需要继续研究新的诊断和治疗策略。代谢组学,一个新兴的领域,提供细胞内所有代谢物的全面分析,组织,系统,或有机体,提供对癌症发展和进展过程中发生的动态变化的关键见解。这篇综述的重点是与BC相关的代谢改变,强调代谢组学在识别早期检测生物标志物方面的潜力,诊断,治疗和预后。代谢组学研究揭示了BC中独特的代谢特征,包括脂质代谢的改变,氨基酸代谢,和能量代谢。这些代谢变化不仅支持癌细胞的快速增殖,而且影响肿瘤微环境和治疗反应。此外,代谢组学在个性化医疗中有着巨大的前景,促进根据个体的代谢概况制定量身定制的治疗策略。通过提供BC代谢变化的整体视图,代谢组学有可能彻底改变我们对疾病的理解并改善患者预后.
    Breast cancer (BC) remains the most prevalent cancer among women worldwide, despite significant advancements in its prevention and treatment. The escalating incidence of BC globally necessitates continued research into novel diagnostic and therapeutic strategies. Metabolomics, a burgeoning field, offers a comprehensive analysis of all metabolites within a cell, tissue, system, or organism, providing crucial insights into the dynamic changes occurring during cancer development and progression. This review focuses on the metabolic alterations associated with BC, highlighting the potential of metabolomics in identifying biomarkers for early detection, diagnosis, treatment and prognosis. Metabolomics studies have revealed distinct metabolic signatures in BC, including alterations in lipid metabolism, amino acid metabolism, and energy metabolism. These metabolic changes not only support the rapid proliferation of cancer cells but also influence the tumour microenvironment and therapeutic response. Furthermore, metabolomics holds great promise in personalized medicine, facilitating the development of tailored treatment strategies based on an individual\'s metabolic profile. By providing a holistic view of the metabolic changes in BC, metabolomics has the potential to revolutionize our understanding of the disease and improve patient outcomes.
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  • 文章类型: Journal Article
    背景:由于化学品的持续和不当使用,包括杀虫剂,许多物质,它们的降解产物可以在土壤中积累并对其生物产生负面影响。
    方法:在本研究中,形态学方法,革兰氏染色,和基质辅助激光解吸/电离飞行时间质谱(MALDI-TOFMS)方法用于从农业土壤中分离细菌,同时使用16SrRNA进行遗传鉴定。使用分光光度法测定细菌的密度,采用气相色谱-质谱(GC-MS)法测定氯氰菊酯的残留量。
    结果:从各种农业土壤中获得了9个分离株。隔离号3显示了对氯氰菊酯的最大有效性,并被选择用于进一步研究。隔离号3被鉴定为中间型苍白杆菌菌株PDB-3,并在国家生物技术信息中心(NCBI)数据库(GenBank:OL587509.1)中注册。使用这个菌株,研究了各种外界因素对氯氰菊酯降解的影响。在最佳条件下(温度:30°C;光密度(OD)=0.2;氯氰菊酯浓度:80±0.02mg/kg),该细菌在20天内表现出氯氰菊酯的100%降解。此外,PDB-3将氯氰菊酯的原始结构改变为各种中间代谢产物,如2-羟基-3-苯氧基苯乙腈,3-苯氧基苯甲醛,3-苯氧基苯甲醛,硬脂酸甲酯,茴香脑,柠檬醛,和苯酚。
    结论:使用PDB-3获得的结果为对氯氰菊酯污染的土壤进行生物修复的大规模田间试验提供了基础。
    BACKGROUND: Due to the constant and improper use of chemicals, including pesticides, many substances, and their degradation products can accumulate in the soil and negatively affect its organisms.
    METHODS: In this study, morphological methods, Gram-staining, and Matrix-Assisted Laser Desorption/Ionzation Time of Flight Mass Spectrometry (MALDI-TOF MS) methods were used to isolate bacteria from agricultural soils, while genetic identification was conducted using 16S rRNA. The density of bacteria was determined using the spectrophotometric method, and the residual amount of cypermethrin was determined and analyzed using Gas chromatograohy-mass spectrometry (GC-MS) methods.
    RESULTS: Nine isolates were obtained from various agricultural soils. Isolate No. 3 showed the greatest effectiveness against cypermethrin and was selected for further research. Isolate No. 3 was identified as the Ochrobactrum intermedium strain PDB-3 and was registered in the National Center for Biotechnology Information (NCBI) database (GenBank: OL587509.1). Using this strain, the influence of various external factors on the degradation of cypermethrin was studied. This bacterium demonstrated 100% degradation of cypermethrin in 20 days under optimal conditions (temperature: 30 °C; optical density (OD) = 0.2; cypermethrin concentration: 80 ± 0.02 mg/kg). In addition, PDB-3 changed the original structure of cypermethrin into various intermediate metabolites, such as 2-hydroxy-3-phenoxy benzeneacetonitrile, 3-phenoxybenzaldehyde, 3-phenoxybenzaldehyde, methyl stearate, anethol, citral, and phenol.
    CONCLUSIONS: The results obtained using PDB-3 provide the basis for large-scale field trials on the bioremediation of cypermethrin-contaminated soils.
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  • 文章类型: Journal Article
    萜类化合物具有显著的生理活性,富含精油。一些萜类化合物具有手性中心,可以形成具有不同生理活性的对映异构体。因此,萜类化合物对映体的提取和分离非常重要,近年来引起了广泛的关注。同时,特定分布和对映体过量的结果(对映体混合物中一种对映体相对于另一种对映体的过量)可以用作非法掺假的质量标记,原产地识别,并探索不同植物组织之间的成分变异和功能相互关系。在这项研究中,综述了近二十年来从精油中提取萜类化合物及其对映体分离的研究进展。通过所得的网络可视化结果来检索提取方法。结果表明,主要的方法是加氢蒸馏,无溶剂微波提取,顶空固相微萃取和超临界流体萃取方法。GC-MS结合手性色谱柱常用于对映体的分离,同时发现2DGC具有更强的分辨率。最后,并对精油的提取和分离鉴定的未来研究方向进行了展望。
    Terpenoids possess significant physiological activities and are rich in essential oils. Some terpenoids have chiral centers and could form enantiomers with distinct physiological activities. Therefore, the extraction and separation of terpenoids enantiomers are very important and have attracted extensive attention in recent years. Meanwhile, the specific distribution and enantiomer excess results (the excess of one enantiomer over the other in a mixture of enantiomers) could be used as quality markers for illegitimate adulteration, origin identification, and exploring component variations and functional interrelations across different plant tissues. In this study, an overview of the progress in the extraction of terpenoids from essential oils and the separation of their enantiomers over the past two decades has been made. Extraction methods were retrieved by the resultant network visualization findings. The results showed that the predominant methods are hydrodistillation, solvent-free microwave extraction, headspace solid-phase microextraction and supercritical fluid extraction methods. GC-MS combined with chiral chromatography columns is commonly used for the separation of enantiomers, while 2D GC is found to have stronger resolution ability. Finally, some prospects for future research directions in the extraction and separation identification of essential oils are proposed.
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  • 文章类型: Journal Article
    次级代谢产物,活生物体产生的生物活性化合物,可以揭示自然界中的共生关系。在这项研究中,从含有次生代谢产物的溶剂上清液中提取与共生细菌(Xenorhabdusstockiae和Photorhabdusluminescens)相关的土传昆虫病原线虫,证明了对大肠杆菌的显著抑制作用,金黄色葡萄球菌,B.subtilus,P.奇迹,E.粪便,还有P.Stutzeri.通过傅立叶变换红外光谱对这些次生代谢物的表征揭示了蛋白质的胺基,多酚的羟基和羧基,多糖的羟基,和有机酸的羧基。此外,通过高效液相色谱法分析获得的粗提物,以基本鉴定潜在的生物活性肽。气相色谱-质谱分析来自Xenorhabdusstoriae的乙酸乙酯提取物确定了主要化合物,包括壬酸衍生物,脯氨酸,巴霉素,八癸醛衍生物,三氧杂-5-氮杂-1-硅双环,4-十八进制,甲酯,油酸,和1,2-苯二羧酸。从发光光纹素中进行额外的提取,产生了功能化合物,例如吲哚-3-乙酸,邻苯二甲酸,1-十四醇,奈莫索诺,1-二十烷醇,和不饱和脂肪酸。这些发现支持用于未来病原体抑制的新型天然抗微生物剂的潜在开发。
    Secondary metabolites, bioactive compounds produced by living organisms, can unveil symbiotic relationships in nature. In this study, soilborne entomopathogenic nematodes associated with symbiotic bacteria (Xenorhabdus stockiae and Photorhabdus luminescens) were extracted from solvent supernatant containing secondary metabolites, demonstrating significant inhibitory effects against E. coli, S. aureus, B. subtilus, P. mirabilis, E. faecalis, and P. stutzeri. The characterization of these secondary metabolites by Fourier transforms infrared spectroscopy revealed amine groups of proteins, hydroxyl and carboxyl groups of polyphenols, hydroxyl groups of polysaccharides, and carboxyl groups of organic acids. Furthermore, the obtained crude extracts were analyzed by high-performance liquid chromatography for the basic identification of potential bioactive peptides. Gas chromatography-mass spectrometry analysis of ethyl acetate extracts from Xenorhabdus stockiae identified major compounds including nonanoic acid derivatives, proline, paromycin, octodecanal derivatives, trioxa-5-aza-1-silabicyclo, 4-octadecenal, methyl ester, oleic acid, and 1,2-benzenedicarboxylicacid. Additional extraction from Photorhabdus luminescens yielded functional compounds such as indole-3-acetic acid, phthalic acid, 1-tetradecanol, nemorosonol, 1-eicosanol, and unsaturated fatty acids. These findings support the potential development of novel natural antimicrobial agents for future pathogen suppression.
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  • 文章类型: Journal Article
    气相色谱(GC)和气相色谱-质谱(GC-MS)分析是从沙特阿拉伯紫蒿中提取的精油(A.judaica)空中部分,从而鉴定出58种成分,占总油组成的93.0%。油主要由单萜(38.6%)组成,倍半萜(14.1%),和其他化合物如乙酯和环酮(40.3%)。确定的主要成分是胡椒酮(16.5%),肉桂酸乙酯(12.9%),和樟脑(百分之九点七)。多元统计分析(MVA),包括主成分分析(PCA)和凝聚层次聚类(AHC)分析,用于将这种油的化学组成与来自不同地区的20种其他A.judaica油进行比较。这项研究揭示了不同的集群,突出独特的化学类型和地理差异。特别是,来自当前研究的油显示出具有显着浓度的特定化合物的专门化学特征,对其独特性做出了重大贡献。对RAW264.7巨噬细胞的进一步细胞毒性测试表明,浓度低于20μg/mL的柔道油适用于未来的药理学研究。这项研究为化学多样性提供了宝贵的见解,地理差异,以及这些精油的潜在生物医学应用。
    Gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) analyses were conducted on essential oil extracted from Saudi Arabian Artemisia judaica L. (A. judaica) aerial parts, resulting in the identification of 58 constituents, representing 93.0% of the total oil composition. The oil primarily consisted of monoterpenes (38.6%), sesquiterpenes (14.1%), and other compounds such as ethyl esters and cyclic ketones (40.3%). The main components identified were piperitone (16.5%), ethyl cinnamate (12.9%), and camphor (9.7%). Multivariate statistical analyses (MVAs), including principal component analysis (PCA) and agglomerative hierarchical clustering (AHC) analysis, were employed to compare the chemical makeup of this oil with 20 other A. judaica oils from various regions. The study revealed distinct clusters, highlighting unique chemotypes and geographic variations. Particularly, the oil from the current study demonstrated a specialized chemical profile with significant concentrations of specific compounds, contributing significantly to its distinctiveness. Further cytotoxicity testing on RAW264.7 macrophages suggested that concentrations below 20 μg/mL of A. judaica oil are suitable for future pharmacological investigations. This study provides valuable insights into the chemical diversity, geographic variations, and potential biomedical applications of these essential oils.
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  • 文章类型: Journal Article
    当前的研究重点是检查从Madhucalengifolia残留物的热解获得的生物燃料的特性,因为选定的森林残留物主要是由其较高的挥发性物质含量引起的。该研究使用了几种分析技术来描述热解油,char,和在固定床反应器中在350至600°C之间进行的缓慢热解过程中获得的气体。最初,过程温度对产品分布的影响进行了评估,以激发最大的热解油产率,发现在475°C的热解温度下为44.2wt%,而炭和气体的产率分别为22.1wt%和33.7wt%,分别。为了确定原料的适用性,通过TGA和FT-IR分析了马德卡的残留,这表明原料可能是一种可行的能源选择。热解油的表征,char,和气体已经通过各种分析方法完成,如FT-IR,GC-MS,和气相色谱法。考察了热解油样品的物理化学特征,结果表明,该油是一种粘性液体,热值低于常规柴油。热解油的FT-IR和GC-MS分析显示存在增加水平的含氧化学品,酸,和苯酚衍生物。碳的FT-IR分析结果表明存在芳烃和脂肪烃。炭中增加的碳含量表明使用固体燃料的可能性。气相色谱法用于检查热解气体的化学结构,结果表明可燃元素的存在。
    The current study focuses on examining the characteristics of biofuel obtained from the pyrolysis of Madhuca longifolia residues, since the selected forest residue was primarily motivated by its greater volatile matter content. The study used several analytical techniques to describe pyrolysis oil, char, and gas obtained from slow pyrolysis process conducted between 350 and 600 °C in a fixed-bed reactor. Initially, the effect of process temperature on product distribution was assessed to motivate maximum pyrolysis oil yield and found to be 44.2 wt% at pyrolysis temperature of 475 °C, while the yields of char and gas were 22.1 wt% and 33.7 wt%, respectively. In order to determine the suitability of the feedstock, the Madhuca longifolia residues were analyzed by TGA and FT-IR, which revealed that the feedstock could be a feasible option as an energy source. The characterization of pyrolysis oil, char, and gas has been done through various analytical methods like FT-IR, GC-MS, and gas chromatography. The physicochemical characteristics of the pyrolysis oil sample were examined, and the results showed that the oil is a viscous liquid with a lower heating value than conventional diesel. The FT-IR and GC-MS analysis of pyrolysis oil revealed the presence of increased levels of oxygenated chemicals, acids, and phenol derivatives. The findings of the FT-IR analysis of char indicated the existence of aromatic and aliphatic hydrocarbons. The increased carbon content in the char indicated the possibility of using solid fuel. Gas chromatography was used to examine the chemical structure of the pyrolysis gas, and the results showed the existence of combustible elements.
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  • 文章类型: Journal Article
    昆虫体内的微生物在维持昆虫的基础生理功能中起着至关重要的作用。嗅觉信号是昆虫生存策略的关键组成部分。钩端孢菌(L.Invasa),一种外来入侵害虫,对桉树造成重大损害,体内有丰富多样的细菌群落。然而,其内源性细菌及其微生物挥发性有机化合物(mVOCs)对入侵乳杆菌行为偏好的影响至今仍未探索。本研究集中于入侵乳杆菌中9种可培养和优势的内源性细菌菌株。用Y管嗅觉计,我们调查了雌性入侵乳杆菌对这些细菌释放的mVOCs的行为反应。同时,气相色谱-质谱(GC-MS)用于定量由这些内源性细菌产生的mVOC。我们的发现揭示了葡萄球菌。表现出最高的入侵乳杆菌吸引力,而微细菌。阴沟肠球菌发挥了最显著的回避作用。对mVOCs的分析进一步强调了醛化合物的重要性,特别是2,3,6-三氯苯甲醛,和烷烃化合物,如二十烷,在介导驱避和吸引效应中。这些结果有助于更深入地了解入侵乳杆菌的入侵机制,并为开发新型生物农药或激发剂提供科学依据。
    Microorganisms within insects play a vital role in maintaining the basal physiological functions of the insects, with olfactory signals as critical components of insect survival strategies. Leptocybe invasa (L. invasa), an invasive alien pest inflicting significant damage to eucalyptus trees, harbors a rich and varied bacterial community within its body. However, the impact of its endogenous bacteria and their microbial Volatile Organic Compounds (mVOCs) on the behavioral preferences of L. invasa remains unexplored to date. This study focused on nine cultivable and dominant endogenous bacterial strains within L. invasa. Using a Y-tube olfactometer, we investigated the behavioral responses of female L. invasa to the mVOCs emitted by these bacteria. Concurrently, gas chromatography-mass spectrometry (GC-MS) was employed to quantify the mVOCs produced by these endogenous bacteria. Our findings revealed that Staphylococcus sp. exhibited the highest attractiveness of L. invasa, whereas Microbacterium sp. and E. cloacae exerted the most significant avoidance effects. The analysis of the mVOCs further highlighted the significance of aldehyde compounds, notably 2,3,6-trichlorobenzaldehyde, and alkane compounds, such as eicosane, in mediating the repellency and attraction effects. These results contribute to a deeper understanding of the invasion mechanism of L. invasa and provide a scientific basis for developing novel biopesticides or elicitors.
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  • 文章类型: Journal Article
    偶氮染料在较大规模的纺织工业中用作着色剂。因此,产生大量的富含染料的废水,其随后造成环境问题。涉及具有偶氮还原酶的细菌的生物工具已被证明在染料废水处理中更有效和高效。目前的工作集中在葡萄球菌caprae(S.caprae)用于活性红195(RR-195)偶氮染料的降解和脱色。为此,pH等因素,温度,接种物,碳源和氮源,和染料浓度已被优化为最大的脱色和降解。S.caprae(4mg/mL)在100µg/mL浓度的静态条件下有效地使RR-195染料脱色90%,30°C和pH7.0,接触时间为12小时。FTIR分析表明,在处理的染料中形成了新的官能团,例如在3370cm-1处的O-H拉伸,在2928cm-1处的C-H谱带拉伸和在1608cm-1处的新谱带,这些谱带指定了芳环的降解,1382和1118cm-1表示脱磺化峰。RR-195染料的生物降解代谢产物,如苯酚,3,5-二叔丁基苯酚,和邻苯二甲酸已经分别被确定为找到工业应用。植物毒性试验表明,处理后的染料对紫花和小麦种子的萌发具有无毒作用。Further,抗生素扩散试验证实了卡雷氏菌的生物安全性。
    Azo dyes are used as coloring agent in textile industries at larger scale. As a result, large quantity of dye-enriched waste water is generated which subsequently poses environmental problems. Biological tool involving bacteria having azoreductase enzyme has proved to be more effective and efficient in dye effluent treatment. Current work focuses on Staphylococcus caprae (S. caprae) for degradation and decolorization of Reactive Red-195 (RR-195) azo dye. For this purpose, factors such as pH, temperature, inoculums, carbon and nitrogen sources, and dye concentrations have been optimized for maximum decolorization and degradation. S. caprae (4 mg/mL) efficiently resulted into 90% decolorization of RR-195 dye under static condition at 100 µg/mL concentration, 30 °C and pH 7.0 at a 12-h contact period. FTIR analysis has revealed the formation of new functional groups in the treated dye such as O-H stretch at 3370 cm-1, C-H band stretching at 2928 cm-1, and new band at 1608 cm-1 which specify the degradation of aromatic ring, 1382 and 1118 cm-1 represents desulfonated peaks. Biodegraded metabolites of RR-195 dye such as phenol, 3, 5-di-tert-butylphenol, and phthalic acid have been identified respectively that find industrial applications. Phytotoxicity test has shown non-toxic effects of treated dye on germination of Vigna radiata and Triticum aestivum seeds. Further, antibiotic diffusion assay has confirmed the biosafety of S. caprae.
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  • 文章类型: Journal Article
    探讨玉米粥的最佳加工工艺,研究了不同烹饪方法和时间下的挥发性化合物和质地。共鉴定出51种玉米粥中的挥发性化合物。值得注意的是,主要挥发物,醛和酯在电压力锅(EPC)中含量相对较高,和酯在烹饪后倾向于显著增加。在醛中,非肛门和己醛由于其含量相对较高,在风味中起着很大的作用。通过多种化学计量学方法可以清楚地区分不同烹饪方法中的玉米粥中的挥发性化合物。此外,质构分析表明,EPC中几乎所有指标都可以在60min时达到最低值。总结一下,与时间相比,不同的烹饪方法对挥发性化合物和质地的影响更大。本研究有助于提高玉米粥的感官属性,从而有助于更健康、更可持续的生产。
    To investigate the optimal processing of maize porridge, the volatile compounds and texture under different cooking methods and time have been studied. A total of 51 volatile compounds were identified in maize porridge. Notably, the major volatiles, aldehydes and esters exhibited a relatively high content in electric pressure cooker (EPC), and esters tend to significantly increase after cooking. Among aldehydes, nonanal and hexanal played a great role in flavor due to their relatively high content. Volatile compounds of maize porridge in different cooking methods could be clearly distinguished by multiple chemometrics. Furthermore, texture analysis revealed that almost all the indicators in the EPC can reach the lowest value at 60 min. To summarize, different cooking methods had a more significant influence on the volatile compounds and texture compared to time. This study helps to improve the sensory attributes of maize porridge, and thus contributes to healthier and more sustainable production.
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