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1.
Molecules ; 29(3)2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38338347

RESUMEN

The flower buds of three Panax species (PGF: P. ginseng; PQF: P. quinquefolius; PNF: P. notoginseng) widely consumed as health tea are easily confused in market circulation. We aimed to develop a green, fast, and easy analysis strategy to distinguish PGF, PQF, and PNF. In this work, fast gas chromatography electronic nose (fast GC e-nose), headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS), and headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) were utilized to comprehensively analyze the volatile organic components (VOCs) of three flowers. Meanwhile, a principal component analysis (PCA) and heatmap were applied to distinguish the VOCs identified in PGF, PQF, and PNF. A random forest (RF) analysis was used to screen key factors affecting the discrimination. As a result, 39, 68, and 78 VOCs were identified in three flowers using fast GC e-nose, HS-GC-IMS, and HS-SPME-GC-MS. Nine VOCs were selected as potential chemical markers based on a model of RF for distinguishing these three species. Conclusively, a complete VOC analysis strategy was created to provide a methodological reference for the rapid, simple, and environmentally friendly detection and identification of food products (tea, oil, honey, etc.) and herbs with flavor characteristics and to provide a basis for further specification of their quality and base sources.


Asunto(s)
Panax , Compuestos Orgánicos Volátiles , Cromatografía de Gases y Espectrometría de Masas/métodos , Nariz Electrónica , Microextracción en Fase Sólida/métodos , Panax/química , Espectrometría de Movilidad Iónica , Compuestos Orgánicos Volátiles/análisis , Flores/química ,
2.
Rapid Commun Mass Spectrom ; 38(6): e9693, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38356085

RESUMEN

RATIONALE: The volatile organic compounds (VOCs) of Lonicerae Japonicae flos (LJF) and Lonicera flos (LF) play a pivotal role in determining their sensory characteristics, medicinal properties, and subsequent impact on market pricing and consumer preferences. However, the differences and specificity of these VOCs remain obscure. Hence, it is crucial to conduct a comprehensive characterization of the VOCs in LJF and LF and pinpoint their potential differential VOCs. METHODS: In this study, headspace gas chromatography-ion mobility spectrometry (HS-GC/IMS) and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC/MS) were employed to comprehensively investigate the compositional characteristics and distinctions in VOCs between LJF and LF. Multivariate statistical analysis was used to identify candidate differential VOCs of LJF and LF samples. RESULTS: A total of 54 and 88 VOCs were identified using HS-GC/IMS and HS-SPME-GC/MS analysis, respectively. Primary VOCs detected in LJF include leaf alcohol, (E)-2-hexen-1-ol dimer, 2-octyn-1-ol, and (E)-3-hexen-1-ol. Key VOCs prevalent in LF encompass farnesol, heptanoic acid, octanoic acid, and valeric acid. Multivariate statistical analysis indicates that compounds such as phenethyl alcohol and leaf alcohol were selected as potential VOCs for distinguishing between LJF and LF. CONCLUSION: This research conducted a comprehensive analysis of the fundamental volatile components in both LJF and LF. It subsequently elucidated the distinctions and specificities within their respective VOC profiles. And this study enables differentiation between LJF and LF through the analysis of VOCs, offering valuable insights for enhancing the quality control of both LJF and LF.


Asunto(s)
Lonicera , Extractos Vegetales , Compuestos Orgánicos Volátiles , Cromatografía de Gases y Espectrometría de Masas/métodos , Compuestos Orgánicos Volátiles/análisis , Microextracción en Fase Sólida/métodos , Espectrometría de Movilidad Iónica , Etanol
3.
PLoS One ; 19(1): e0297493, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38277418

RESUMEN

Staphylococcus aureus is the main culprit, causing a variety of severe clinical infections. At the same time, clinics are also facing the severe situation of antibiotic resistance. Therefore, effective strategies to address this problem may include expanding the antimicrobial spectrum by exploring alternative sources of drugs or delaying the development of antibiotic resistance through combination therapy so that existing antibiotics can continue to be used. Plumbagin (PLU) is a phytochemical that exhibits antibacterial activity. In the present study, we investigated the in vitro antibacterial activity of PLU. We selected five antibiotics with different mechanisms and inhibitory activities against S. aureus to explore their interaction with the combination of PLU. The interaction of combinations was evaluated by the Bliss independent model and visualized through response surface analysis. PLU exhibited potent antibacterial activity, with half maximal inhibitory concentration (IC50) and minimum inhibitory concentration (MIC) values against S. aureus of 1.73 µg/mL and 4 µg/mL, respectively. Synergism was observed when PLU was combined with nitrofurantoin (NIT), ciprofloxacin (CPR), mecillinam (MEC), and chloramphenicol (CHL). The indifference of the trimethoprim (TMP)-PLU pairing was demonstrated across the entire dose-response matrix, but significant synergy was observed within a specific dose region. In addition, no antagonistic interactions were indicated. Overall, PLU is not only a promising antimicrobial agent but also has the potential to enhance the growth-inhibitory activity of some antibiotics against S. aureus, and the use of the interaction landscape, along with the dose-response matrix, for analyzing and quantifying combination results represents an improved approach to comprehending antibacterial combinations.


Asunto(s)
Antiinfecciosos , Staphylococcus aureus Resistente a Meticilina , Naftoquinonas , Infecciones Estafilocócicas , Humanos , Antibacterianos/farmacología , Staphylococcus aureus , Sinergismo Farmacológico , Antiinfecciosos/farmacología , Pruebas de Sensibilidad Microbiana
4.
J Pharm Biomed Anal ; 239: 115910, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38101240

RESUMEN

Xiaoyao Wan (XYW) is a prescription medicine of traditional Chinese medicine (TCM) with the effects of "soothing the liver and relieving depression," and "strengthening spleen and nourishing blood". XYW has been widely concerned in the treatment of depression and has become one of the commonly used classic formulas in clinical practice. However, the pharmacodynamic substance basis and the quality control studies of XYW are hitherto quite limited. Here, we aim to fully utilize an advanced ultra - performance liquid chromatography-quadrupole - Orbitrap mass spectrometry (UPLC-Q-Orbitrap-MS), headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) technique to deep characterization of the pharmacological substance basis and quantitatively evaluate the quality of XYW. Firstly, 299 compounds were identified or tentatively characterized, including 198 non-volatile organic compounds (n-VOCs) and 101 volatile organic compounds (VOCs). Secondly, principal component analysis (PCA) and hierarchical cluster analysis (HCA) was used to analyze quality differences in XYW at different manufacturers. Thirdly, a parallel reaction monitoring (PRM) method was established and validated to quantify the fourteen major effective substances in different manufacturers of XYW, which were chosen as the benchmarked substances to evaluate the quality of XYW. In conclusion, this study shows that the strategy provides a useful method for quality control of TCM and offers a practical workflow for exploring the quality consistency of TCM.


Asunto(s)
Medicamentos Herbarios Chinos , Compuestos Orgánicos Volátiles , Cromatografía de Gases y Espectrometría de Masas/métodos , Microextracción en Fase Sólida/métodos , Cromatografía Líquida de Alta Presión , Compuestos Orgánicos Volátiles/análisis
5.
Foods ; 12(18)2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37761044

RESUMEN

This work was designed to investigate the dynamic changes process of non-volatile organic compounds (n-VOCs) and volatile organic compounds (VOCs) in mulberries during different growth periods using UPLC-Q-Orbitrap-MS, HS-SPME-GC-MS, and HS-GC-IMS. A total of 166 compounds were identified, including 68 n-VOCs and 98 VOCs. Furthermore, principal component analysis (PCA), random forest analysis (RFA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to analyze differences in mulberries at different ripening stages. A total of 74 compounds appeared or disappeared at different ripening periods and 24 compounds were presented throughout the growth process. Quantitative analysis and antioxidant experiments revealed that as the mulberries continued to mature, flavonoids and phenolic acids continued to increase, and the best antioxidant activity occurred from stage IV. Conclusively, an effective strategy was established for analyzing the composition change process during different growth periods, which could assist in achieving dynamic change process analysis and quality control.

6.
J Pharm Biomed Anal ; 236: 115715, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37769526

RESUMEN

Huo-Xiang-Zheng-Qi oral liquid (HXZQOL) is a well-known traditional Chinese medicine formula for the treatment of gastrointestinal diseases, with the pharmacologic effects of antiinflammatory, immune protection and gastrointestinal motility regulation. More significantly, HXZQOL is recommended for the treatment of COVID-19 patients with gastrointestinal symptoms, and it has been clinically proven to reduce the inflammatory response in patients with COVID-19. However, the effective and overall quality control of HXZQOL is currently limited due to its complex composition, especially the large amount of volatile and non-volatile active components involved. In this study, aimed to fully develop a comprehensive strategy based on non-targeted multicomponent identification, targeted authentication and quantitative analysis for quality evaluation of HXZQOL from different batches. Firstly, the non-targeted high-definition MSE (HDMSE) approach is established based on UHPLC/IM-QTOF-MS, utilized for multicomponent comprehensive characterization of HXZQOL. Combined with in house library-driven automated peak annotation and comparison of 47 reference compounds, 195 components were initially identified. In addition, HS-SPME-GC-MS was employed to analyze the volatile organic compounds (VOCs) in HXZQOL, and a total of 61 components were identified by comparison to the NIST database, reference compounds as well as retention indices. Secondly, based on the selective ion monitoring (SIM) of 24 "identity markers" (involving each herbal medicine), characteristic chromatograms (CCs) were established on LC-MS and GC-MS respectively, to authenticate 15 batches of HXZQOL samples. The targeted-SIM CCs showed that all marker compounds in 15 batches of samples could be accurately monitored, which could indicate preparations authenticity. Finally, a parallel reaction monitoring (PRM) method was established and validated to quantify the nine compounds in 15 batches of HXZQOL. Conclusively, this study first reports chemical-material basis, SIM CCs and quality evaluation of HXZQOL, which is of great implication to quality control and ensuring the authenticity of the preparation.


Asunto(s)
COVID-19 , Medicamentos Herbarios Chinos , Humanos , Qi , Cromatografía Líquida de Alta Presión/métodos , Medicina Tradicional China , Espectrometría de Masas , Medicamentos Herbarios Chinos/análisis
7.
Artículo en Inglés | MEDLINE | ID: mdl-37453388

RESUMEN

Shuang-Huang-Lian powder injection (SHLPI) is a natural drug injection made of honeysuckle, scutellaria baicalensis and forsythia suspensa. It has the characteristics of complex chemical composition and difficult metabolism research in vivo. LC-MS platform has been proven to be an important analytical technology in plasma metabolomics. Unfortunately, the lack of an effective sample preparation strategy before analysis often significantly impacts experimental results. In this work, twenty-one extraction protocols including eight protein precipitation (PPT), eight liquid-liquid extractions (LLE), four solid-phase extractions (SPE), and one ultrafiltration (U) were simultaneously evaluated using plasma metabolism of SHLPI in vivo. In addition, a strategy of "feature ion extraction of the multi-component metabolic platform of traditional Chinese medicine" (FMM strategy) was proposed for the in-depth characterization of metabolites after intravenous injection of SHLPI in rats. The results showed that the LLE-3 protocol (Pentanol:Tetrahydrofuran:H2O, 1:4:35, v:v:v) was the most effective strategy in the in vivo metabolic detection of SHLPI. Furthermore, we used the FMM strategy to elaborate the in vivo metabolic pathways of six representative substances in SHLPI components. This research was completed by ion migration quadrupole time of flight mass spectrometer combined with ultra high performance liquid chromatography (UPLC/Vion™-IMS-QTof-MS) and UNIFI™ metabolic platform. The results showed that 114 metabolites were identified or preliminarily identified in rat plasma. This work provides relevant data and information for further research on the pharmacodynamic substances and in vivo mechanisms of SHLPI. Meanwhile, it also proves that LLE-3 and FMM strategies could achieve the in-depth characterization of complex natural drug metabolites related to Shuang-Huang-Lian in vivo.


Asunto(s)
Medicamentos Herbarios Chinos , Ratas , Animales , Polvos , Espectrometría de Masas , Cromatografía Liquida , Medicamentos Herbarios Chinos/química , Cromatografía Líquida de Alta Presión/métodos
8.
Rapid Commun Mass Spectrom ; 37(7): e9479, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-36690334

RESUMEN

RATIONALE: Shuang-Huang-Lian powder injection (SHLPI) is a well-known modern traditional Chinese medicine formula preparation (TCMFP) widely used to treat acute upper respiratory infections. However, SHLPI is extracted from pure Chinese medicine and administered through an injection, and many adverse reactions have been reported clinically. Therefore, it is necessary to characterize in depth the chemical composition of SHLPI and quantitatively analyze its potential allergenic components. METHODS: In this study, the samples were analyzed using ion mobility ultra-high-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UHPLC-QTOF-MS) combined with a self-built database. Furthermore, the parallel reaction monitoring (PRM) model of ultra-high-performance liquid chromatography-quadrupole-Orbitrap-mass spectrometry (UHPLC-Q-Orbitrap-MS) was used to successfully quantify 10 representative bioactive components. RESULTS: Using this strategy 90 compounds were identified, the fragmentation pathways of five representative compounds in the five main components of SHLPI were summarized, and 10 components (neochlorogenic acid, chlorogenic acid, sweroside, forsythiaside A, luteoloside, isochlorogenic acid B, isochlorogenic acid C, baicalin, phillyrin, and baicalein) were determine as the quality markers of SHLPI based on UPLC-Q-Orbitrap-MS. CONCLUSIONS: This work comprehensively characterized the material basis of SHLPI, summarized the cracking laws of representative substances, and quantitatively analyzed 10 potential allergenic components. Therefore, this study could provide a basis for the quality control of SHLPI and the clinical rational use of drugs to reduce its adverse reactions.


Asunto(s)
Medicamentos Herbarios Chinos , Cromatografía Líquida de Alta Presión/métodos , Polvos , Medicamentos Herbarios Chinos/química , Espectrometría de Masas
9.
Foods ; 11(22)2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36429337

RESUMEN

The pericarps of Zanthoxylum bungeanum (ZBP) and leaves of Zanthoxylum bungeanum (ZBL) are popular spices in China, and they have pharmacological activities as well. In this experiment, the volatile organic compounds (VOCs) of the pericarps of Zanthoxylum bungeanum in Sichuan (SJ) and its leaves (SJY) and the pericarps of Zanthoxylum bungeanum in Shaanxi (SHJ) and its leaves (SHJY) were analyzed by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). The fingerprint of HS-GC-IMS and the heat maps of HS-SPME-GC-MS were established. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were performed. The results showed that a total of 95 components were identified, 62 components identified by HS-SPME-GC-MS and 40 components identified by HS-GC-IMS, of which 7 were the same. The analysis found that SJ and SHJ were obviously distinguished, while SJY and SHJY were not. There were considerably fewer VOCs in the leaves than in the pericarps. In the characterization of the VOCs of ZBL and ZBP, the flavor of ZBP was more acrid and stronger, while the flavor of ZBL was lighter and slightly acrid. Thirteen and eleven differential markers were identified by HS-GC-IMS and HS-SPME-GC-MS, respectively. This is helpful in distinguishing between SHJ and SJ, which contributes to their quality evaluation.

10.
Rapid Commun Mass Spectrom ; 36(20): e9363, 2022 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-35902380

RESUMEN

RATIONALE: Many methods have been reported for the production of rare ginsenosides, including heat treatment, acid hydrolysis, alkaline hydrolysis, enzymatic hydrolysis, and microbial transformation. However, the conversion of original ginsenosides to rare ginsenosides under the dual conditions of citric acid and high-pressure steam sterilization has rarely been reported. METHODS: In this study, a method involving ultrahigh-performance liquid chromatography coupled to ion mobility quadrupole time-of-flight mass spectrometry was developed for analysis of chemical transformation of protopanaxatriol (PPT)-type ginsenosides Rg1 and Re, protopanaxadiol (PPD)-type ginsenoside Rb1 , and total ginsenosides in the dual conditions of citric acid and high-pressure steam sterilization. An internal ginsenoside database containing 126 known ginsenosides and 18 ginsenoside reference compounds was established to identify the transformation products and explore possible transformation pathways and mechanisms. RESULTS: A total of 54 ginsenosides have been preliminarily identified in the transformation products of PPD-type ginsenosides Rg1 and Re, PPD-type ginsenoside Rb1 , and total ginsenosides, and the possible transformation pathways were as follows: Rg1 , Re → 20(S)-Rh12 , 20(R)-Rh12 ; Rg1 , Re → 20(S)-Rh1 , 20(R)-Rh1 → Rk3 , Rh4 , Rh5 ; Rb1 → gypenoside LXXV; Rb1 → 20(S)-Rg3 , 20(R)-Rg3 → Rk1 , Rg5 ; Re → 20(S)-Rg2 , 20(R)-Rg2 → 20(S)-Rf2 , 20(R)-Rf2 , Rg4 , F4 . CONCLUSIONS: The results elucidated the possible transformation pathways and mechanisms of ginsenosides in the dual conditions of citric acid and high-pressure steam sterilization, which were helpful for revealing the mechanisms of ginsenosides and enhanced safety and quality control of pharmaceuticals and nutraceuticals. Meanwhile, a simple, efficient, and practical method was developed for the production of rare ginsenosides, which has the potential to produce diverse rare ginsenosides on an industrial scale.


Asunto(s)
Ginsenósidos , Panax , Cromatografía Liquida , Ácido Cítrico , Ginsenósidos/química , Espectrometría de Masas , Panax/química , Saponinas , Vapor/análisis , Triterpenos
11.
J Pharm Biomed Anal ; 206: 114385, 2021 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-34597841

RESUMEN

Kai-Xin-San (KXS) is a traditional Chinese medicine (TCM) formula containing four herbal medicines: Ginseng Radix Rhizoma, Polygalae Radix, Poria and Acori Tatarinowii Rhizoma. A large number of pharmacological studies in vitro and in vivo have shown that KXS is characterized by anti-depression, anti-Alzheimer's disease, anti-oxidation and other activities. However, the pharmacodynamic substance basis studies of KXS are hitherto quite limited. Here, KXS was identified and determined by ultra-performance liquid chromatography-quadrupole-Orbitrap mass spectrometry (UPLC-Q-Orbitrap MS) and gas chromatography-mass spectrometry (GC-MS). Firstly, the data-dependent acquisition mode (DDA) of UPLC-Q-Orbitrap MS combined with the inclusion list were used to collected the chemical composition. The chemical constituents of KXS were identified by local database on compound discoverer™ 3.1 software and Xcalibur 4.1 software. With the use of this approach, a total of 211 compounds were identified from KXS. Wherein 60 compounds were from Ginseng Radix Rhizoma, 40 compounds were from Poria, and 111 compounds were from Polygala Radix, respectively. Secondly, 105 volatile constituents were identified by GC-MS analysis, which were mainly derived from Acori Tatarinowii Rhizoma. Besides, an adjusted parallel reaction monitoring method was established and validated to quantify the seventeen major compounds in different herbal medicines of KXS, which were chosen as the benchmarked substances to evaluate the quality of KXS. In conclusion, this study provided a generally applicable strategy for global metabolite identification of the complicated components and determination of multi-component content in traditional Chinese medicines.


Asunto(s)
Medicamentos Herbarios Chinos , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Cromatografía de Gases y Espectrometría de Masas , Espectrometría de Masas
12.
Molecules ; 25(16)2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32824271

RESUMEN

Gynostemma pentaphyllum (thumb.) Makino is a functional herbal tea commonly used in Asian countries and regions to reduce blood lipid levels. G. pentaphyllum saponin is the main component, but there are still a large number of components with lipid-lowering activity that have not been found. In this study, 10 novel dammarane-type saponins, (1-10) and a known one (11) were isolated from G. pentaphyllum. Ten new compounds were identified and named as yunnangypenosides A-J (1-10), and another known one (11) was also obtained. Their chemical structures were determined by MS, NMR spectroscopic analyses. Moreover, the cytotoxicities on human HepG-2 hepatocellular carcinoma cells of these isolates were evaluated, and the results showed that compounds 1-11 had no obvious cytotoxicity. Finally, all these compounds were evaluated for their lipid-lowering effect by means of the oil red O staining method. Ten compounds could significantly reduce lipid levels except of 2, especially 8 exhibite the strongest hypolipidemia activity.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Gynostemma/química , Hipolipemiantes/farmacología , Extractos Vegetales/farmacología , Saponinas/farmacología , Triterpenos/química , Carcinoma Hepatocelular/patología , Proliferación Celular , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Estructura Molecular , Saponinas/química , Tés de Hierbas/análisis , Damaranos
13.
Molecules ; 24(7)2019 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-30987109

RESUMEN

Russula vinosa Lindbl is a wild edible mushroom that is usually used for original material of food and soup and has rich nutritional value. What are the nutritional ingredients? In order to answer this question, we investigated the chemical constituents of this wild functional food. Six new compounds (1-6), together with nine known ones (7-15), were isolated from R. vinosa. The six new compounds were named as vinosane (1), rulepidadione C (2), (24E)-3,4-seco-cucurbita-4,24-diene-26,29-dioic acid-3-methyl ester (3), (24E)-3,4-seco-cucurbita-4,24-diene-26-oic acid-3-ethyl ester (4), (24E)-3ß-hydroxycucurbita-5,24-diene-26,29-dioic acid (5), and (2S,3S,4R,2'R)-2-(2'-hydroxydocosanoylamino)eicosane-1,3,4-triol (6). Their structures were determined based on spectroscopic methods including HR-ESI-MS, 1D, and 2D NMR. Moreover, a cell counting kit-8 (CCK-8 kit) was used to screen for the cytotoxicity of compounds 1-5 and 7-13 on mouse macrophage RAW 264.7 cells. The results showed that compounds 1-5 and 7-13 had no obvious cytotoxicity. In addition, the inhibitory effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-activated mouse macrophage RAW 264.7 cells were evaluated. Compounds 1, 3, 4, 7, 12, and 13 showed moderate inhibitory activity on NO production.


Asunto(s)
Agaricales/química , Productos Biológicos/química , Productos Biológicos/farmacología , Óxido Nítrico/biosíntesis , Nutrientes/química , Animales , Productos Biológicos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Ratones , Estructura Molecular , Nutrientes/aislamiento & purificación , Células RAW 264.7 , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Análisis Espectral
14.
Zhongguo Zhong Yao Za Zhi ; 43(6): 1209-1214, 2018 Mar.
Artículo en Chino | MEDLINE | ID: mdl-29676130

RESUMEN

A new method for detection of Escherichia coli exist in licorice decoction was developed by using DNA-based electrochemical biosensor. The thiolated capture probe was immobilized on a gold electrode at first. Then the aptamer for Escherichia coli was combined with the capture probe by hybridization. Due to the stronger interaction between the aptamer and the E. coli, the aptamer can dissociate from the capture probe in the presence of E. coli in licorice decoction. The biotinylated detection probe was hybridized with the single-strand capture probe. As a result, the electrochemical response to Escherichia coli can be measured by using differential pulse voltammetric in the presence of α-naphthyl phosphate. The plot of peak current vs. the logarithm of concentration in the range from 2.7×10² to 2.7×108 CFU·mL⁻¹ displayed a linear relationship with a detection limit of 50 CFU·mL⁻¹. The relative standard deviation of 3 successive scans was 2.5%,2.1%,4.6% for 2×10²ï¼Œ2×104,2×106:6 CFU·mL⁻¹ E. coli, respectively. The proposed procedure showed better specificity to E. coli in comparison to Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis. In the detection of the real extractum glycyrrhizae, the results between the proposed strategy and the GB assay showed high degree of agreement, demonstrating the designed biosensor could be utilized as a powerful tool for microbial examination for traditional Chinese medicine.


Asunto(s)
Técnicas Biosensibles , Medicamentos Herbarios Chinos/análisis , Escherichia coli/aislamiento & purificación , Glycyrrhiza/microbiología , Extractos Vegetales/análisis , ADN , Contaminación de Medicamentos , Oro
15.
Appl Microbiol Biotechnol ; 97(21): 9503-14, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24037307

RESUMEN

Arthrobacter simplex 156 is a microorganism that is used for steroid drug biotransformation of cortisone acetate (CA) to prednisone acetate (PA). The enzyme 3-ketosteroid-△(1)-dehydrogenase encoded by the ksdD gene plays an important role in the bioconversion process. To further improve the biotransformation efficiencies of the industrial strain, a genetic manipulation system for A. simplex 156 was developed. Additional copies of the ksdD gene under the control of the cat promoter (from pXMJ19) were transferred into the strain A. simplex 156 and integrated into the 16S rDNA sites, yielding a series of recombinant strains. One of these recombinant strains, designated A. simplex M158, exhibited superior properties for CA biotransformation. At the substrate concentration of 83.6 g/l, the highest PA production of the recombinant strain reached 66.7 g/l, which is approximately 32.9 % higher than that of wild-type strains, and the incubation time for CA to PA bioconversion was reduced by 20 h. Southern blotting analysis of the recombinant strain indicated two copies of deregulated ksdD genes were integrated into the 16S rDNA sites, which means two of five 16S rRNA operons were insertionally disrupted in the recombinant strain. However, the disruption of the two 16S rRNA operons did not affect the growth rate of the recombinant strain, which survived and thrived under desired conditions. In addition, the new strain was genetically stable for more than 100 generations without the use of antibiotics for selection. These superior characteristics make the new strain more suitable than the wild-type strain for PA production.


Asunto(s)
Arthrobacter/enzimología , Arthrobacter/metabolismo , Cortisona/análogos & derivados , Ingeniería Metabólica , Oxidorreductasas/metabolismo , Prednisona/metabolismo , Arthrobacter/genética , Arthrobacter/crecimiento & desarrollo , Biotransformación , Cortisona/metabolismo , Dosificación de Gen , Expresión Génica , Inestabilidad Genómica , Oxidorreductasas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
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