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1.
Yale J Biol Med ; 93(2): 265-275, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32607087

RESUMO

Hydrastis canadensis, commonly known as goldenseal, is a botanical native to the southeastern United States that has been used for the treatment of infection. The activity of goldenseal is often attributed to the presence of alkaloids (cyclic, nitrogen-containing compounds) present within its roots. Chemical components of botanical supplements like goldenseal may face degradation if not stored properly. The purpose of the research was to analyze the stability of known and unknown metabolites of H. canadensis during exposure to different storage conditions using mass spectrometry. Three abundant metabolites of H. canadensis, berberine, canadine, and hydrastine, were chosen for targeted analysis, and the stability of unknown metabolites was evaluated using untargeted metabolomics. The analysis and evaluation of H. canadensis samples were performed utilizing LC-MS and Principal Component Analysis (PCA). The research project focused on identifying the chemical changes in the metabolite content of H. canadensis under different temperature conditions (40°C ± 5°C, 20°C ± 5°C , and 4°C ± 5°C), different light:dark (hr:hr) cycles (16:8, 12:12, and 0:24), and different sample conditions (powdered roots versus whole roots) over a six month period. The results of this 6-month study revealed that the storage conditions evaluated had no significant effects on the chemical composition of H. canadensis roots. Hence, as long as H. canadensis roots are stored within the storage conditions tested in the study, no significant changes in chemical compositions of metabolites are expected.


Assuntos
Alcaloides de Berberina , Armazenamento de Medicamentos , Hydrastis , Preparações de Plantas , Benzilisoquinolinas/análise , Berberina/análogos & derivados , Berberina/análise , Alcaloides de Berberina/análise , Alcaloides de Berberina/farmacologia , Estabilidade de Medicamentos , Armazenamento de Medicamentos/métodos , Armazenamento de Medicamentos/normas , Humanos , Infecções/tratamento farmacológico , Espectrometria de Massas/métodos , Preparações de Plantas/química , Preparações de Plantas/farmacologia , Raízes de Plantas/química , Análise de Componente Principal/métodos
2.
Nat Prod Rep ; 36(6): 869-888, 2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31187844

RESUMO

Covering: 2000 to 2019 According to a 2012 survey from the Centers for Disease Control and Prevention, approximately 18% of the U.S. population uses natural products (including plant-based or botanical preparations) for treatment or prevention of disease. The use of plant-based medicines is even more prevalent in developing countries, where for many they constitute the primary health care modality. Proponents of the medicinal use of natural product mixtures often claim that they are more effective than purified compounds due to beneficial "synergistic" interactions. A less-discussed phenomenon, antagonism, in which effects of active constituents are masked by other compounds in a complex mixture, also occurs in natural product mixtures. Synergy and antagonism are notoriously difficult to study in a rigorous fashion, particularly given that natural products chemistry research methodology is typically devoted to reducing complexity and identifying single active constituents for drug development. This report represents a critical review with commentary about the current state of the scientific literature as it relates to studying combination effects (including both synergy and antagonism) in natural product extracts. We provide particular emphasis on analytical and Big Data approaches for identifying synergistic or antagonistic combinations and elucidating the mechanisms that underlie their interactions. Specific case studies of botanicals in which synergistic interactions have been documented are also discussed. The topic of synergy is important given that consumer use of botanical natural products and associated safety concerns continue to garner attention by the public and the media. Guidance by the natural products community is needed to provide strategies for effective evaluation of safety and toxicity of botanical mixtures and to drive discovery in botanical natural product research.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Antagonismo de Drogas , Combinação de Medicamentos , Sinergismo Farmacológico , Echinacea/microbiologia , Endotoxinas/farmacologia , Humanos , Metabolômica/métodos , Extratos Vegetais/efeitos adversos , Extratos Vegetais/farmacocinética
3.
J Pharm Biomed Anal ; 160: 443-477, 2018 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-30142565

RESUMO

Echinacea purpurea (L.) Moench, Echinacea angustifolia DC. var. angustifolia and Echinacea pallida (Nutt.) Nutt. are frequently used as medicinal plants and their preparations are among the most widely used herbal medicines. The extracts from these species have shown a highly complex chemical composition, including polar compounds (caffeic acid derivatives, CADs), non-polar compounds (alkylamides and acetylenic secondary metabolites; essential oil) and high molecular weight constituents (polysaccharides and glycoproteins). All these chemical classes of compounds have demonstrated to possess interesting biological activities. In the light of all the above, this paper is focused on the analytical techniques, including sample preparation tools and chromatographic procedures, for the chemical analysis of bioactive compounds in medicinally used Echinacea species. Since sample preparation is considered to be a crucial step in the development of analytical methods for the determination of constituents present in herbal preparations, the strength and weakness of different extraction techniques are discussed. As regards the analysis of compounds present in Echinacea plant material and derivatives, the application of different techniques, mainly HPLC, HPLC-ESI-MS, HPLC-ESI-MS/MS, HPCE, HPTLC and GC, is discussed in detail. The strength, weakness and applicability of the different separation tools are stated.


Assuntos
Técnicas de Química Analítica/métodos , Echinacea/química , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Raízes de Plantas/química
4.
Planta Med ; 84(9-10): 721-728, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29571174

RESUMO

Botanical medicines have been utilized for centuries, but it remains challenging to identify bioactive constituents from complex botanical extracts. Bioassay-guided fractionation is often biased toward abundant or easily isolatable compounds. To comprehensively evaluate active botanical mixtures, methods that allow for the prioritization of active compounds are needed. To this end, a method integrating bioassay-guided fractionation, biochemometric selectivity ratio analysis, and molecular networking was devised and applied to Angelica keiskei to comprehensively evaluate its antimicrobial activity against Staphylococcus aureus. This approach enabled the identification of putative active constituents early in the fractionation process and provided structural information for these compounds. A subset of chalcone analogs were prioritized for isolation, yielding 4-hydroxyderricin (1, minimal inhibitory concentration [MIC] ≤ 4.6 µM, IC50 = 2.0 µM), xanthoangelol (2, MIC ≤ 4.0 µM, IC50 = 2.3) and xanthoangelol K (4, IC50 = 168 µM). This approach allowed for the identification of a low-abundance compound (xanthoangelol K) that has not been previously reported to possess antimicrobial activity and facilitated a more comprehensive understanding of the compounds responsible for A. keiskei's antimicrobial activity.


Assuntos
Angelica/química , Anti-Infecciosos/farmacologia , Chalcona/análogos & derivados , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Bioensaio , Chalcona/química , Chalcona/isolamento & purificação , Chalcona/farmacologia , Cromatografia Líquida , Espectrometria de Massas , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química
5.
Nat Prod Commun ; 13(11)2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31080542

RESUMO

The antibiotic resistant threat is continuing to grow, due in part to the overuse of antibiotics in livestock feed. Many nations in Europe have banned the use of antibiotics in feed, leading to higher rates of infection in livestock animals and reduced productivity for the food market. Increasingly, researchers are looking into the efficacy of phytopreparations to replace antibiotics in feed, allowing for increased animal health without the development of resistance. Macleaya cordata, or Chinese plume poppy, shows promise as a food additive. To evaluate the antimicrobial efficacy of this plant, we tested in vitro activity of M. cordata extract, as well as pure compounds sanguinarine and chelerythrine against wild-type, methicillin-resistant, and multiply-resistant strains of Staphylococcus aureus (SA1199, AH1263, and IA116, respectively). Combination tests to evaluate synergy, additivity, and antagonism within the extract were also completed for the first time. Sanguinarine and chelerythrine showed complete growth inhibition of all strains of S. aureus at concentrations ranging from 3-10 µg/mL, and were equal in activity or were more potent than the reference compound chloramphenicol. Combination studies of pure sanguinarine and chelerythrine with M. cordata extract revealed additivity or indifference of mixture components with these compounds. Because sanguinarine and chelerythrine represent the major active constituents of M. cordata, the pooled amounts of these two compounds may be useful for establishing potency for quality control purposes. This is the first report of activity of chelerythrine and sanguinarine against methicillin-resistant S. aureus AH1263 and multiply-resistant S. aureus IA116, and illustrates the promise of M. cordata extract as an alternative to antibiotics in feed additives.

6.
Planta Med ; 82(14): 1236-45, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27399234

RESUMO

Angelica keiskei Koidzumi, or ashitaba, is a popular botanical medicine in Japan containing diverse bioactive components including prenylated chalcones, linear and angular coumarins, and flavanones. This review provides an overview of the current knowledge of ashitaba metabolites and their biological activities to prioritize future studies. Ashitaba is purported to possess cytotoxic, antidiabetic, antioxidative, anti-inflammatory, antihypertensive, and antimicrobial properties. Although many in vitro studies have been conducted on ashitaba's chemical constituents, the in vivo efficacy and clinical relevance of this plant has yet to be confirmed for most of these activities. Here we describe the chemical composition of ashitaba and present the pharmacological effects of this botanical as supported by the current literature. The experimental results demonstrate promise for the medical use of ashitaba, but considerable work needs to be done to understand the mechanisms of action of its metabolites. Additionally, in vivo and clinical trials as well as additional studies on less abundant bioactive compounds are warranted.


Assuntos
Angelica/química , Extratos Vegetais/uso terapêutico , Animais , Humanos , Japão , Extratos Vegetais/toxicidade , Plantas Medicinais/toxicidade
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