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1.
Phys Chem Chem Phys ; 25(24): 16559-16569, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37309184

RESUMO

The coexistence of spin-orbit coupling and piezoelectricity in a single material may have potential application in multifunctional devices, including spintronics, nanorobotics and piezotronics. Spin-orbit coupling provides a new means to manipulate electron's spin without an additional external magnetic field, while piezoelectricity refers to the interplay between mechanical stresses and electric polarization. Using first-principles calculations, the structural, electronic, optical, spin, and piezoelectric properties of the Janus Ge2XY (X ≠ Y = P, As, Sb, and Bi) monolayers were systematically investigated. All the Ge2XY are energetically and dynamically stable in the α phase. At the GW level, Ge2AsSb, Ge2AsBi, and Ge2SbBi have direct fundamental band gaps of 0.65, 0.64, and 0.91 eV. At the GW + BSE level, their optical gaps are 0.42, 0.45, and 0.63 eV, and the optical absorption coefficients can reach about 10-5 cm-1 in the infrared light region, which reveals that they have potential for application in infrared photodetectors. For Ge2PBi, Ge2AsBi, and Ge2SbBi containing the heavy Bi element, the lowermost conduction band and uppermost valence band have large spin splitting along the M-K and K-Γ lines, and the bands near the Fermi level possess Rashba spin splitting at the Γ point. Ge2PBi and Ge2SbBi have both large in-plane piezoelectric coefficients d11 (-0.75 and -3.18 pm V-1) and out-of-plane piezoelectric coefficients d31 (0.37 and 0.30 pm V-1). Our findings are helpful to understand the mechanism of the spin-orbit physics and piezoelectricity of Janus Ge2XY monolayers and guide experiments in exploring novel multifunctional materials.

2.
Zhongguo Zhong Yao Za Zhi ; 48(4): 890-899, 2023 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-36872259

RESUMO

Complicated chemical reactions occur in the decoction of traditional Chinese medicines(TCMs) which features complex components, influencing the safety, efficacy, and quality controllability of TCMs. Therefore, it is particularly important to clarify the chemical reaction mechanism of TCMs in the decoction. This study summarized eight typical chemical reactions in the decoction of TCMs, such as substitution reaction, redox reaction, isomerization/stereoselective reaction, complexation, and supramolecular reaction. With the "toxicity attenuation and efficiency enhancement" of aconitines and other examples, this study reviewed the reactions in decoction of TCMs, which was expected to clarify the variation mechanisms of key chemical components in this process and to help guide medicine preparation and safe and rational use of medicine in clinical settings. The current main research methods for chemical reaction mechanisms of decoction of TCMs were also summed up and compared. The novel real-time analysis device of decoction system for TCMs was found to be efficient and simple without the pre-treatment of samples. This device provides a promising solution, which has great potential in quantity evaluation and control of TCMs. Moreover, it is expected to become a foundational and exemplary research tool, which can advance the research in this field.


Assuntos
Medicina , Medicina Tradicional Chinesa , Projetos de Pesquisa
3.
J Ethnopharmacol ; 307: 116204, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36720435

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Semen Ziziphi Spinosae (SZS), the seed of Ziziphus jujuba var. spinosa (Bunge) Hu ex H.F. Chow (Chinese name Suan-Zao-Ren), is widely distributed in China, Laos, Myanmar, and Iran. It is a classic traditional Chinese medicine with sedative and sleeping effects. In clinical practice, there are more than 155 proprietary Chinese medicines containing SZS. However, many commercial SZS products are difficult to qualify using current methods. Moreover, there is a scarcity of quality standards for SZS in proprietary Chinese medicines. AIM OF THE STUDY: The purpose of this study was to clearly reveal the quality indicators during the entire production process of SZS and its products. MATERIALS AND METHODS: This study reviewed more than 230 articles and related books on the quality control of SZS and its proprietary Chinese medicines published over the last 40 years (from January 1979 to October 2022). Moreover, where available, information on the quality of SZS and its proprietary Chinese medicines was also collected from websites for comparison, including online publications (e.g. PubMed, CNKI, Google Scholar, and Web of Science), the information at Yaozhi website and China Medical Information Platform, along with some classic books on Chinese herbal medicine. The literature and information search were conducted using keywords such as "Suan-Zao-Ren", " Ziziphus jujuba" and "quality control", and the latest results from various databases were combined to obtain valid information. The active components, which in vivo exposure, and Q-markers were also summarized. RESULTS: The jujuboside A, jujuboside B, and spinosin were revealed as the key Q-markers for SZS. Moreover, the advancements and prospects of the quality control for SZS and its extract, proprietary Chinese medicines, health foods, and adulterants were comprehensively summarized. The high-performance liquid chromatography-UV/evaporative light scattering detection and fingerprint analysis were found to be the mainstream methods for the SZS quality control. In particular, the novel quality evaluation method based on the unit content was applied for SZS and its proprietary Chinese medicines. Significant fluctuations were found in the contents of Q-markers. Moreover, the mass transfer rule of Q-markers was comprehensively clarified based on the entire production process, including production origins, ripening time, primary process, processing, compatibility decoction/extract, and storage. Ultimately, the crushing and compatibility of SZS were found to be the key steps affecting the active components. CONCLUSIONS: In short, this study provides solid evidences to reveal quality indicators for the entire production process of developing rational quality standards for SZS and its products. Moreover, this study also provides a template quality control overview, which could be extended to other traditional Chinese medicines.


Assuntos
Medicamentos de Ervas Chinesas , Ziziphus , Medicamentos de Ervas Chinesas/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Medicina Tradicional Chinesa , Controle de Qualidade
4.
Front Pharmacol ; 13: 883898, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35662724

RESUMO

The herb-pair ginseng-Fuzi (the root of Aconitum carmichaelii) is the material basis of Shenfu prescriptions and is popular in traditional Chinese medicine for the treatment of heart failure, and even shock with severe-stage of COVID-19. A narrow therapeutic window of Fuzi may cause significant regional loss of property and life in clinics. Therefore, systemic elucidation of active components is crucial to improve the safety dose window of Shenfu oral prescriptions. A high performance liquid chromatography-mass spectrometry method was developed for quantification of 10 aconitines in SD rat plasma within 9 min. The limit of detection and the limit of quantification were below 0.032 ng/ml and 0.095 ng/ml, respectively. Furthermore, a systemic comparison with their pharmacokinetic characteristics after oral administration of a safe dosage of 2 g/kg of Fuzi and ginseng-Fuzi decoction for 24 h was conducted. Eight representative diester, monoester, and non-ester aconitines and two new active components (i.e., songorine and indaconitine) were all adopted to elucidating the differences of the pharmacokinetic parameters in vivo. The compatibility of Fuzi and ginseng could significantly increase the in vivo exposure of active components. The terminal elimination half-life and the area under the concentration-time curve of mesaconitine, benzoylaconitine, benzoylmesaconitine, benzoylhypaconitine, and songorine were all increased significantly. The hypaconitine, benzoylmesaconitine, and songorine were regarded as the main active components in vivo, which gave an effective clue for the development of new Shenfu oral prescriptions.

5.
Phytomedicine ; 100: 154059, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35338992

RESUMO

BACKGROUND: The synergic action of compound prescriptions is an important feature and core advantage of traditional medicine. Ginseng-Fuzi decoction is a classic compatible phytomedicine in China, of which Ginseng can effectively reduce the toxicity of Fuzi in clinical, but the detoxification chemical mechanism is still unclear. PURPOSE: Develop a novel method for real-time tracking and monitoring of complex substances in the decoction system of traditional Chinese medicine to uncover the detoxification effect Ginseng on Fuzi and explore the possible chemical reaction mechanism of Ginseng-Fuzi co-decoction. METHODS: A novel real-time monitoring system, online filtration electrospray ionization mass spectrometry, was developed for extremely complex substances analysis in the decoction of traditional medicine compounds to uncover the directionally detoxification effect and the mechanism of compatibility interaction. RESULTS: Nine key alkaloids and 7 ginsenosides in Ginseng-Fuzi decoction were simultaneously in-situ monitoring in positive ion mode or negative ion mode respectively. Both types of targeted analytes had satisfactory MS signal response for real-time qualitative and quantitative analysis with high precision (RSD < 14.04%) and low LLODs (0.002 ng/ml-10 ng/ml). Through long-term tracking analysis, the exact detoxification and synergistic effect of Ginseng-Fuzi decoction were confirmed as the concentration of main toxic alkaloids decreased (e.g. the content of mesaconitine has been reduced by about 38%) and the main active monoester alkaloids increased obviously. More importantly, the possible molecular mechanism of the detoxification effect of Ginseng compatibility was revealed for the first time, which was the nucleophilic substitution reaction of diester alkaloids catalyzed by fatty acids. CONCLUSION: This study revealed the exact effect of co-decoction of Ginseng and Fuzi at the molecular level and the chemical reaction mechanism of fatty acid-catalyzed degradation of toxic diester-type alkaloids. The comprehensive multi-component real-time monitoring strategy for complex traditional medicine compounds developed and implemented here has important demonstration significance for revealing the scientific connotation of the compatibility of compound traditional medicine.


Assuntos
Aconitum , Alcaloides , Medicamentos de Ervas Chinesas , Panax , Aconitum/química , Alcaloides/química , Cromatografia Líquida de Alta Pressão/métodos , Diterpenos , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas por Ionização por Electrospray/métodos
6.
Zhongguo Zhong Yao Za Zhi ; 47(1): 279-284, 2022 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-35178935

RESUMO

Quality is the guarantee for the clinical safety and effectiveness of Chinese medicine. Accurate quality evaluation is the key to the standardization and modernization of Chinese medicine. Efforts have been made in improving Chinese medicine quality and strengthening the quality and safety supervision in China, but rapid and accurate quality evaluation of complex Chinese medicine samples is still a challenge. On the basis of the development of ambient mass spectrometry and the application in quality evaluation of complex Chinese medicine systems in recent years, the authors developed the multi-scenario Chinese medicine quality evaluation strategies. A systematic methodology was proposed in specific areas such as real-time monitoring of the quality of complex Chinese medicine decoction system, rapid toxicity grading of compound Chinese patent medicine, and evaluation of bulk medicinals of Chinese patent medicine. Allowing multi-scenario analysis of Chinese medicine, it is expected to provide universal research ideas and technical methods for rapid and accurate quality evaluation of Chinese medicine and boost the high-quality development of Chinese medicine industry.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , China , Espectrometria de Massas , Medicamentos sem Prescrição , Padrões de Referência
7.
Phytochemistry ; 194: 113030, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34839132

RESUMO

Panax notoginseng is a highly valuable and widely used herb in traditional Chinese medicine. The quality and efficacy of Panax notoginseng grown under different conditions can greatly vary due to the differences in chemical composition. The analysis of chemical composition in Panax notoginseng typically involves various experimental steps including extraction, chromatographic separation and characterization, which can be time- and labor-consuming. Therefore, the efficient quality assessment and control of Panax notoginseng requires the development of more rapid methods for the chemical characterization and classification of Panax notoginseng. In this study, a method based on internal extractive electrospray ionization mass spectrometry (iEESI-MS) was developed to characterize chemical components of Panax notoginseng samples under different growth conditions (e.g., place of origin, soil quality, growth season) at the speed of 0.5 min per sample, without sample pretreatment and chromatographic separation. A total of 35 chemical components, including sugars, saponins, organic acids, etc., were identified in Panax notoginseng samples. Clear separation was observed in the multivariate analysis of the iEESI-MS data from Panax notoginseng samples grown under different conditions. The difference in the content of sucrose, fructose, Rg1, Rf, Rb1, Noto-R1, malonyl-Rb1, malonyl-Rg1, malonyl-Rf, Rd, Re, linoleic acid, palmitic acid and malic acid can be used as key characteristic indicators to discriminate origin, commercial specifications, and cultivation conditions of Panax notoginseng samples. The results of our study indicate the high power of iEESI-MS for the rapid molecular characterization and classification of Panax notoginseng under different growth conditions, which can be used for the quality assessment of traditional herbal medicines as well as in pharmaceutical and clinical analysis.


Assuntos
Panax notoginseng , Saponinas , Medicina Tradicional Chinesa , Análise Multivariada , Espectrometria de Massas por Ionização por Electrospray
8.
Biomed Chromatogr ; 35(12): e5175, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34390018

RESUMO

Viscum articulatum Burm. f. is a parasitic plant rich in flavonoids, triterpenoids, and catechins and has a high nutritional value. It has been reported that consuming V. articulatum can prevent cardiac diseases. In this study, six bioactive compounds, including catechins, triterpenoids, and phenylpropanoid glycosides, were determined in alcohol extracts of the plant using HPLC. The anti-inflammatory and antioxidant activities of three catechins, two triterpenoids, and three combination drugs were measured in cardiomyocytes, and the results showed that the anti-inflammatory activity was significantly enhanced while retaining strong antioxidant activity when epicatechin and ursolic acid were used in combination. The main quality markers epicatechin and ursolic acid were screened based on the specificity of the genuine herb and a potent synergistic effect, and the lowest limitation contents of V. articulatum which could discriminate it from some other taxonomically similar materials were accordingly determined. This self-built lowest limitation content of the two screened quality markers could quickly and accurately reflect the efficacy in terms of chemical composition and reverse the disorderly market use of nongenuine herbs or confusing species for adulteration. This study is of some significance for market regulation, drug development, and clinical medication.


Assuntos
Extratos Vegetais , Viscum , Animais , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/toxicidade , Catequina/análise , Linhagem Celular , Sobrevivência Celular , Cromatografia Líquida de Alta Pressão/métodos , Glicosídeos/análise , Limite de Detecção , Modelos Lineares , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Ratos , Reprodutibilidade dos Testes , Triterpenos/análise , Viscum/química , Viscum/classificação
9.
J Ethnopharmacol ; 277: 114233, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34044077

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The genus Viscum comprises approximately 100 species that are mainly distributed across Africa, Asia and Europe. The extracts and preparations of Viscum species are widely used as common complementary and alternative medicines in the treatment of rheumatism and cancer. AIM OF THE REVIEW: This review aims to explore the medicinal properties of twelve species belonging to the genus Viscum for potential therapeutic applications. MATERIALS AND METHODS: We collected online information (including PubMed, CNKI, Google Scholar, and Web of Science) from January 1915 to April 2021 and knowledge from classical books on Chinese herbal medicines available for 12 species of the genus Viscum, including Viscum coloratum (Kom.) Nakai, Viscum album L., Viscum articulatum Burm. f., Viscum liquidambaricola Hayata, Viscum ovalifolium DC., Viscum capitellatum Sm., Viscum cruciatum Sieber ex Boiss., Viscum nudum Danser, Viscum angulatum B.Heyne ex DC., Viscum tuberculatum A.Rich., Viscum multinerve Hayata, and Viscum diospyrosicola Hayata. RESULTS: At least 250 different compounds have been reported across twelve Viscum species, including amino acid and peptides, alkaloids, phenolic acids, flavonoids, terpenoids, carbohydrates, fatty acids, lipids, and other types of compounds. In particular, for Viscum coloratum (Kom.) Nakai and Viscum album L., the plants, preparations, and bioactive components have been thoroughly reviewed. This has allowed to elucidate the role of active components, including lectins, viscotoxins, flavonoids, terpenoids, phenolic acids, and polysaccharides, in multiple bioactivities, such as anti-cancer, anti-rheumatism arthralgia, anti-inflammation, anti-cardiovascular diseases, enhancing immunity, and anti-chemotherapy side effects. We also evaluated quality control methods based on active compounds, in vivo exposure compounds, and discriminated chemical markers. CONCLUSIONS: This is the first report to systematically review the pharmaceutical development history, chemical composition, clinical evidence, pharmacological activity, discriminated chemical markers, in vivo exposure, and quality control on twelve distinct species of Viscum plants with medicinal properties. The significant safety and efficacy, along with the minor side effects are constantly confirmed in clinics. The genus Viscum is thus an important medicinal resource that is worth exploring and developing in future pharmacological and chemical studies.


Assuntos
Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Viscum/química , Animais , Etnofarmacologia , Humanos , Medicina Tradicional/métodos , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/efeitos adversos
10.
Zhongguo Zhong Yao Za Zhi ; 46(6): 1357-1367, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-33787132

RESUMO

The growth years of traditional Chinese medicinal materials are closely related to their quality, which directly affects the efficacy and safety of clinical medication. Therefore, it is particularly important to establish an identification method for the growth years of traditional Chinese medicinal materials. In this review, the identification methods for the growth years of traditional Chinese medicinal materials were summarized systematically, and were divided into four types according to the identification principles and methods: traditional identification, molecular identification, physical/chemical identification, and integrated identification. Relying on rich experience, objective molecular markers, various physical/chemical methods and integrated identification techniques(including infrared spectroscopy, nuclear magnetic resonance spectroscopy, high performance liquid chromatography, gas chromatography, mass spectrometry, bionic identification technology and their tandem technologies, etc.), the differences of characters or chemical fingerprints were compared in depth. The growth years of traditional Chinese medicinal materials were quickly identified or predicted by the appearance and characters, the whole fingerprint information or the content of specific chemical markers, and their content ratios. Through the case analysis of mature varieties, we intend to promote the establishment of a perfect technology system for the identification of the growth years of traditional Chinese medicinal materials, and to provide a reference for other perennial herbal materials, finally resulting in the accurate and precise quality control of traditional Chinese medicinal materials.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , China , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Humanos
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