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1.
Microsc Microanal ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39353875

RESUMO

Macro- and microscopic techniques have long been used to describe plant materials and establish plant structural profiles. These techniques are commonly used in botanical authentication to identify the genuine and closely allied species used in botanical research. Advanced microscopic techniques were used in this study to differentiate three different Piper species used as kava or kava-kava. The genuine species is Piper methysticum and the other two species commonly called false-kava or kava-kava, are Piper auritum and Piper excelsum. Macroscopic characteristics, including a black-spotted stem and fibrous root, are characteristic of P. methysticum, whereas the stem of P. auritum is greenish with no spots, and the P. excelsum stem is purple-pink. Microscopic attributes include the characteristic collenchyma of stems and the pattern of arrangement of peripheral and medullary vascular bundles. The starch grains are smaller in P. excelsum than in the other two species. Energy-dispersive X-ray spectroscopy analysis of the crystals indicates the expected calcium, magnesium, and silica, along with lesser amounts of sodium, and potassium. The crystals present in the Piper species vary in shape, size, and elemental composition. Combining macro- and microscopical techniques and resulting characteristics are instrumental in differentiating the three Piper species.

2.
J Diet Suppl ; : 1-26, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39381905

RESUMO

Since its establishment in 1994, the National Center for Natural Products Research (NCNPR) at the University of Mississippi has made notable contributions to the field of natural product research, coinciding with the passage of the Dietary Supplement Health and Education Act. Over the past three decades, the Center has focused on studying plants, herbs, and other natural materials for applications in medicine, agriculture, and nutraceuticals, particularly in the area of botanical dietary supplements. NCNPR scientists have been actively engaged in developing and improving quality control measures to help ensure the safety of dietary supplements in response to a growing market. The Center's research efforts have led to its designation as a U.S. Food and Drug Administration Center of Excellence, reflecting its role in advancing scientific understanding of natural products. Through collaborations with various stakeholders and regulators, NCNPR has contributed to shaping the regulatory landscape for botanical dietary supplements, highlighting both their potential health benefits and associated risks, such as product adulteration. The Center's influence is also evident internationally, as demonstrated by its annual International Conference on the Science of Botanicals, which will mark its 26th year in April 2025. This overview outlines NCNPR's role in supporting research, regulation, and safety in the natural products field.

3.
Planta Med ; 90(7-08): 631-640, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38843801

RESUMO

Many polyprenylated acylphloroglucinols with fascinating chemical structures and intriguing biological activities have been identified as key to phytochemicals isolated from Garcinia, Hypericum, and related genera. In the present work, two chiral, tautomeric, highly-oxygenated polyprenylated acylphloroglucinols tethered with acyl and prenyl moieties on a bicyclo[3.3.1]nonanetrione core were isolated from the 95% ethanolic extract of Garcinia gummi-gutta fruit. The structures of both compounds were elucidated based on the NMR and MS data with ambiguity in the exact position of the enol and keto functions at C-1 and C-3 of the core structure. The structures of both polyprenylated acylphloroglucinols were established as a structurally revised guttiferone J and the new iso-guttiferone J with the aid of gauge-independent atomic orbital NMR calculations, CP3 probability analyses, specific rotation calculations, and electronic circular dichroism calculations in combination with the experimental data. The structures of both compounds resemble hyperforin, a potent activator of the human pregnane X receptor. As expected, both compounds showed strong pregnane X receptor activation at 10 µM [7.1-fold (guttiferone J) and 5.0-fold (iso-guttiferone J)], explained by a molecular docking study, necessitating further in-depth investigation to substantiate the herb-drug interaction potential of G. gummi-gutta upon co-administration with pharmaceutical drugs.


Assuntos
Garcinia , Espectroscopia de Ressonância Magnética , Garcinia/química , Estrutura Molecular , Frutas/química , Benzofenonas/química , Benzofenonas/isolamento & purificação , Benzofenonas/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Floroglucinol/química , Floroglucinol/isolamento & purificação , Humanos
4.
Artigo em Inglês | MEDLINE | ID: mdl-38557311

RESUMO

Aleurites moluccanus (candlenut) and Bertholletia excelsa (Brazil nut) are marketed as dietary supplements for weight loss. These dietary supplements have been found to sometimes be adulterated with toxic nuts/seeds from Cascabela thevetia, commonly known as yellow oleander or lucky nut. This study emphasizes the key identification parameters to differentiate the genuine and adulterated nuts. Samples were obtained from authenticated sources of the nuts and from commercial sources of dietary supplements. This study examined 38 samples, including voucher and commercial samples. All eight commercial candlenut dietary supplement samples were adulterated. Additionally, two samples sold as Brazil nuts were also found to be adulterated. Other nuts were screened for the presence of Cardiac Glycosides, but none were found to be positive. The presence of yellow oleander was confirmed in all commercial dietary supplement samples marketed as candlenut as well as in commercial samples of Brazil nut. This study provides simple key identification characters using micro-morphology and histochemical localization of cardiac glycosides in the commercial nuts, HPTLC fingerprints, and LC-DAD-Q-ToF analytical parameters to detect and identify adulteration in commercial products.


Assuntos
Bertholletia , Suplementos Nutricionais , Suplementos Nutricionais/análise , Bertholletia/química , Contaminação de Alimentos/análise , Cromatografia em Camada Fina , Nozes/química , Cromatografia Líquida de Alta Pressão , Redução de Peso , Microscopia
5.
Nat Prod Res ; : 1-9, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38449104

RESUMO

One undescribed compound, striasinol (1), and twelve previously described compounds were isolated from the aerial parts of Striga asiatica. Structure elucidation of isolated compounds was achieved by the interpretation of 1D and 2D NMR and HRESIMS data. The absolute configuration (1S,5S) of 1 was ascertained based on GIAO NMR calculations, DP4+ probability analysis, and a comparison of the experimental and calculated specific rotation values. The isolated compounds were evaluated for their antimalarial action, and none was found to be effective against the chloroquine-sensitive (D6) or chloroquine-resistant (W2) strains of Plasmodium falciparum. The isolates were found non-toxic to the Vero cell line as well. Subsequent testing of these metabolites for antimicrobial activities against various bacterial and fungal strains (up to 20 µg/mL), revealed that compounds 6 (chryseriol) and 7 (apigenin) showed a reasonable activity towards methicillin-resistant Staphylococcus aureus ATCC 1708 (MRSA), with IC50 values of 5.81 and 3.60 µg/mL, respectively.

6.
Bioorg Med Chem Lett ; 101: 129650, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38341161

RESUMO

Two leuconoxine-type diazaspiroindole alkaloids, the known compound, (+)-melodinine E (1), and its new analogue, (+)-11-chloromelodinine E (2), were isolated from the stems of Cryptolepis dubia (Burm.f.) M.R. Almeida (Apocynaceae), collected in Laos. The chemical structures of these compounds were determined by analysis of their spectroscopic data and by comparison of these data with literature values, of which the molecular structure of 1 has been determined previously by analysis of its single-crystal X-ray diffraction data. The absolute configurations of 1 and 2 have been defined by their experimental and simulated electronic circular dichroism (ECD) spectroscopic data and supported by 1H and 13C NMR-based DP4+ probability analysis and specific rotation calculations. When tested against a small panel of human cancer cell lines, these two compounds exhibited selective cytotoxicity toward OVCAR3 human ovarian cancer cells.


Assuntos
Antineoplásicos , Alcaloides Indólicos , Neoplasias Ovarianas , Feminino , Humanos , Cryptolepis , Apoptose , Linhagem Celular Tumoral , Estrutura Molecular
8.
Plants (Basel) ; 13(2)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38256784

RESUMO

Oxidosqualene cyclases (OSCs) are the key enzymes accountable for the cyclization of 2,3-oxidosqualene to varied triterpenoids and phytosterols. Hoodia gordonii (from the family Apocynaceae), a native of the Kalahari deserts of South Africa, Namibia, and Botswana, is being sold as a prevalent herbal supplement for weight loss. The appetite suppressant properties are attributed to P57AS3, an oxypregnane steroidal glycoside. At the molecular level, the enzymes involved in the biosynthesis of triterpenes and phytosterols from H. gordonii have not been previously reported. In the current study, predicted transcripts potentially encoding oxidosqualene cyclases were recognized first by searching publicly available H. gordonii RNA-seq datasets. Two OSC-like sequences were selected for functional analysis. A monofunctional OSC, designated HgOSC1 which encodes lupeol synthase, and HgOSC2, a multifunctional cycloartenol synthase forming cycloartenol and other products, were observed through recombinant enzyme studies. These studies revealed that distinct OSCs exist for triterpene formation in H. gordonii and provided opportunities for the metabolic engineering of specific precursors in producing phytosterols in this plant species.

9.
J Biol Chem ; 300(3): 105647, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38219818

RESUMO

Pea phytoalexins (-)-maackiain and (+)-pisatin have opposite C6a/C11a configurations, but biosynthetically how this occurs is unknown. Pea dirigent-protein (DP) PsPTS2 generates 7,2'-dihydroxy-4',5'-methylenedioxyisoflav-3-ene (DMDIF), and stereoselectivity toward four possible 7,2'-dihydroxy-4',5'-methylenedioxyisoflavan-4-ol (DMDI) stereoisomers was investigated. Stereoisomer configurations were determined using NMR spectroscopy, electronic circular dichroism, and molecular orbital analyses. PsPTS2 efficiently converted cis-(3R,4R)-DMDI into DMDIF 20-fold faster than the trans-(3R,4S)-isomer. The 4R-configured substrate's near ß-axial OH orientation significantly enhanced its leaving group abilities in generating A-ring mono-quinone methide (QM), whereas 4S-isomer's α-equatorial-OH was a poorer leaving group. Docking simulations indicated that the 4R-configured ß-axial OH was closest to Asp51, whereas 4S-isomer's α-equatorial OH was further away. Neither cis-(3S,4S)- nor trans-(3S,4R)-DMDIs were substrates, even with the former having C3/C4 stereochemistry as in (+)-pisatin. PsPTS2 used cis-(3R,4R)-7,2'-dihydroxy-4'-methoxyisoflavan-4-ol [cis-(3R,4R)-DMI] and C3/C4 stereoisomers to give 2',7-dihydroxy-4'-methoxyisoflav-3-ene (DMIF). DP homologs may exist in licorice (Glycyrrhiza pallidiflora) and tree legume Bolusanthus speciosus, as DMIF occurs in both species. PsPTS1 utilized cis-(3R,4R)-DMDI to give (-)-maackiain 2200-fold more efficiently than with cis-(3R,4R)-DMI to give (-)-medicarpin. PsPTS1 also slowly converted trans-(3S,4R)-DMDI into (+)-maackiain, reflecting the better 4R configured OH leaving group. PsPTS2 and PsPTS1 provisionally provide the means to enable differing C6a and C11a configurations in (+)-pisatin and (-)-maackiain, via identical DP-engendered mono-QM bound intermediate generation, which PsPTS2 either re-aromatizes to give DMDIF or PsPTS1 intramolecularly cyclizes to afford (-)-maackiain. Substrate docking simulations using PsPTS2 and PsPTS1 indicate cis-(3R,4R)-DMDI binds in the anti-configuration in PsPTS2 to afford DMDIF, and the syn-configuration in PsPTS1 to give maackiain.


Assuntos
Pisum sativum , Proteínas de Plantas , Pterocarpanos , Pisum sativum/química , Pisum sativum/metabolismo , Pterocarpanos/química , Pterocarpanos/metabolismo , Estereoisomerismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Modelos Moleculares , Conformação Molecular
10.
J Biomol Struct Dyn ; 42(2): 903-917, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37059719

RESUMO

Pregnane X receptor (PXR), extensively expressed in human tissues related to digestion and metabolism, is responsible for recognizing and detoxifying diverse xenobiotics encountered by humans. To comprehend the promiscuous nature of PXR and its ability to bind a variety of ligands, computational approaches, viz., quantitative structure-activity relationship (QSAR) models, aid in the rapid dereplication of potential toxicological agents and mitigate the number of animals used to establish a meaningful regulatory decision. Recent advancements in machine learning techniques accommodating larger datasets are expected to aid in developing effective predictive models for complex mixtures (viz., dietary supplements) before undertaking in-depth experiments. Five hundred structurally diverse PXR ligands were used to develop traditional two-dimensional (2D) QSAR, machine-learning-based 2D-QSAR, field-based three-dimensional (3D) QSAR, and machine-learning-based 3D-QSAR models to establish the utility of predictive machine learning methods. Additionally, the applicability domain of the agonists was established to ensure the generation of robust QSAR models. A prediction set of dietary PXR agonists was used to externally-validate generated QSAR models. QSAR data analysis revealed that machine-learning 3D-QSAR techniques were more accurate in predicting the activity of external terpenes with an external validation squared correlation coefficient (R2) of 0.70 versus an R2 of 0.52 in machine-learning 2D-QSAR. Additionally, a visual summary of the binding pocket of PXR was assembled from the field 3D-QSAR models. By developing multiple QSAR models in this study, a robust groundwork for assessing PXR agonism from various chemical backbones has been established in anticipation of the identification of potential causative agents in complex mixtures.


Assuntos
Relação Quantitativa Estrutura-Atividade , Receptores de Esteroides , Humanos , Receptor de Pregnano X , Receptores de Esteroides/química , Aprendizado de Máquina , Misturas Complexas
11.
J Diet Suppl ; 21(3): 281-293, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37794652

RESUMO

Arthrospira/Limnospira is a popular botanical dietary supplement throughout the world and has been consumed as a food product for hundreds of years. Ongoing efforts from our research group are focused on evaluating the utility of a Limnospira-derived oral supplement (Immulina) in promoting resilience against influenza viral infection. Like other botanical extracts, Immulina is inherently a complex matrix with variation in the levels of its chemical constituents. Therefore, to ensure therapeutic consistency for future scientific research and clinical studies, we are developing standardization technology using a bioassay and chemical markers. Braun-type lipoproteins, a class of macromolecules that activate the Toll-like receptor (TLR)2/TLR1 signaling pathway, have been identified as a major active component within Immulina. Based on the mechanism of action of the Braun-type lipoproteins, an in vitro bioassay was established using the HEK-Blue hTLR2/TLR1 cell line to quantitate the immune-enhancing potency of Immulina. The objective of the current research was to validate that bioassay for Immulina activity quantification using the U.S. FDA guidance document for botanical drug development and U.S. Pharmacopeia recommendations. System suitability, reference standards and defining potency units were established. Validation of performance parameters included precision, specificity, accuracy, linearity, and range. Validating this bioassay for Immulina activity provides a tool for ensuring product consistency and quantifying the potency of this botanical for use in future research as well as material in the consumer market.


Assuntos
Spirulina , Spirulina/química , Receptor 2 Toll-Like , Receptor 1 Toll-Like , Receptores Toll-Like , Bioensaio , Lipoproteínas
12.
Artigo em Inglês | MEDLINE | ID: mdl-38101286

RESUMO

Peppermint essential oil (EO) has a multitude of applications, such as a fragrance in cosmetics, personal care and industrial products, or as a flavoring ingredient in food and beverages. Despite its popularity and economic significance, peppermint EO is often adulterated to reduce production costs and to increase profits. Although the ISO standard for peppermint EO exists, detecting sophisticated forms of adulteration remains challenging.The current study used conventional and chiral GC/MS analysis of volatiles compounds, and chemometric techniques to evaluate an extensive set of authentic peppermint EO (n = 22) and commercial products (n = 36) purported to contain peppermint EO. Specifically, thirty-six terpenoids were examined in each sample and compared with the ISO standard. Fifty-three percent of the selected commercial products did not meet the ISO specifications and the ratio between menthone/isomenthone was proven to be a good indicator for authentication and adulteration detection. Chiral GC/MS was further employed to measure eight terpenoids: α-pinene, ß-pinene, limonene, menthol, menthone, isomenthone, pulegone, and menthyl acetate. The enantiomeric compositions of 27 commercial products were above or below the norm measured from authentic peppermint EOs. Of the 27 samples, eight met the ISO standard. A sample class prediction (SCP) model based on partial least squares-discriminant analysis (PLS-DA) of conventional GC/MS data was constructed using authentic peppermint EOs and cornmint EOs. The model can distinguish the most common types of peppermint EOs (US, India, and US/India blend) and cornmint EOs sold in the US market. After construction, the SCP model was then used to analyze commercial samples. One sample, which passed both ISO specification and chiral analysis, was identified as outlier by the SCP model. Overall, the applicability of combining both conventional and chiral GC/MS along with chemometric tools has been successfully demonstrated to address the overall quality of peppermint EOs in commerce and may help combat sophisticated adulteration.


Assuntos
Monoterpenos Cicloexânicos , Mentha piperita , Mentol , Óleos Voláteis , Quimiometria , Óleos Voláteis/análise , Terpenos
13.
Prog Chem Org Nat Prod ; 122: 163-219, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37392312

RESUMO

The widespread utility of herbal products has been rising considerably worldwide, including both developed and developing countries, leading to the rapid growth of their availability in the United States and globally. This substantial increase in consumption of herbal products has witnessed the emergence of adverse effects upon oral administration of certain of these products, and thus has raised safety concerns. The adverse effects caused by the consumption of certain botanical medicines occur primarily as a result of the poor quality of plant raw materials or the finished products, which inherently may affect safety and/or efficacy. The poor quality of some herbal products can be attributed to a lack of proper quality assurance and quality control. A high demand for herbal products that surpasses production, combined with a desire for maximizing profits, along with a lack of rigorous quality control within some manufacturing facilities have led to the emergence of quality inconsistencies. The underlying causes for this involve the misidentification of plant species, or their substitution, adulteration, or contamination with harmful ingredients. Analytical assessments have revealed there to be frequent and significant compositional variations between marketed herbal products. The inconsistency of the quality of herbal products can be ascribed essentially to the inconsistency of the botanical raw material quality used to manufacture the products. Thus, the quality assurance and the quality control of the botanical raw materials is may contribute significantly to improving the quality and consistency of the quality of the end products. The current chapter focuses on the chemical evaluation of quality and consistency of herbal products, including botanical dietary supplements. Different techniques, instruments, applications, and methods used in identifying, quantifying, and generating chemical fingerprints and chemical profiles of the ingredients of the herbal products will be described. The strengths and weaknesses of the various techniques available will be addressed. Limitations of the other approaches including morphological or microscopic analysis and DNA-based analysis will be presented.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Administração Oral , Comércio , Suplementos Nutricionais , Contaminação de Medicamentos , Veículos Farmacêuticos
14.
Int J Mol Sci ; 24(14)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37511246

RESUMO

Identifying novel phytochemical secondary metabolites following classical pharmacognostic investigations is tedious and often involves repetitive chromatographic efforts. During the past decade, Ultra-High Performance Liquid Chromatography-Quadrupole Time of Flight-Tandem Mass Spectrometry (UHPLC-QToF-MS/MS), in combination with molecular networking, has been successfully demonstrated for the rapid dereplication of novel natural products in complex mixtures. As a logical application of such innovative tools in botanical research, more than 40 unique 3-oxy-, 3, 6-dioxy-, and 3, 6, 27-trioxy-steroidal saponins were identified in aerial parts and rhizomes of botanically verified Smilax sieboldii. Tandem mass diagnostic fragmentation patterns of aglycones, diosgenin, sarsasapogenin/tigogenin, or laxogenin were critical to establishing the unique nodes belonging to six groups of nineteen unknown steroidal saponins identified in S. sieboldii. Mass fragmentation analysis resulted in the identification of 6-hydroxy sapogenins, believed to be key precursors in the biogenesis of characteristic smilaxins and sieboldins, along with other saponins identified within S. sieboldii. These analytes' relative biodistribution and characteristic molecular networking profiles were established by analyzing the leaf, stem, and root/rhizome of S. sieboldii. Deducing such profiles is anticipated to aid the overall product integrity of botanical dietary supplements while avoiding tedious pharmacognostic investigations and helping identify exogenous components within the finished products.


Assuntos
Saponinas , Smilax , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Distribuição Tecidual , Saponinas/química , Extratos Vegetais
15.
J Nat Prod ; 86(7): 1786-1792, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37450763

RESUMO

Bioassay-guided fractionation of the essential oil of Santalum album led to the identification of α-santalol (1) and ß-santalol (2) as new chemotypes of cannabinoid receptor type II (CB2) ligands with Ki values of 10.49 and 8.19 µM, respectively. Nine structurally new α-santalol derivatives (4a-4h and 5) were synthesized to identify more selective and potent CB2 ligands. Compound 4e with a piperazine structural moiety demonstrated a Ki value of 0.99 µM against CB2 receptor and did not show binding activity against cannabinoid receptor type I (CB1) at 10 µM. Compounds 1, 2, and 4e increased intracellular calcium influx in SH-SY5Y human neuroblastoma cells that were attenuated by CB2 antagonism or inverse agonism, supporting the results that these compounds are CB2 agonists. Molecular docking showed that 1 and 4e had similar binding poses, exhibiting a unique interaction with Thr114 within the CB2 receptor, and that the piperazine structural moiety is required for the binding affinity of 4e. A 200 ns molecular dynamics simulation of CB2 complexed with 4e confirmed the stability of the complex. This structural insight lays a foundation to further design and synthesize more potent and selective α-santalol-based CB2 ligands for drug discovery.


Assuntos
Agonismo Inverso de Drogas , Neuroblastoma , Humanos , Simulação de Acoplamento Molecular , Ligantes , Receptores de Canabinoides , Piperazinas/farmacologia , Receptor CB2 de Canabinoide , Receptor CB1 de Canabinoide , Estrutura Molecular , Relação Estrutura-Atividade
16.
Chem Res Toxicol ; 36(6): 818-821, 2023 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-37255213

RESUMO

The French Lentil & Leek Crumbles frozen food product was recently recalled due to reports of gastrointestinal issues. So far, 393 adverse illness complaints and 133 hospitalizations have been reported from consumption of this food, and the tara (Tara spinosa) protein flour ingredient is hypothesized to be responsible. A multipronged approach resulted in identification of (S)-(-)-baikiain in tara as a compound of interest due to its abundance, possible metabolic fate, and close resemblance to irreversible inhibitors of L-pipecolate oxidase. Oral administration of baikiain in ND4 mice showed a statistically significant increase in blood ALT levels and a reduction in liver GSH.


Assuntos
Lens (Planta) , Animais , Camundongos , Farinha , Cebolas , Alimentos Congelados , Fígado
17.
Phytochemistry ; 212: 113732, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37245686

RESUMO

Often, chiral natural products exist as single stereoisomers; however, simultaneous occurrences of both enantiomers can exist in nature, resulting in scalemic or racemic mixtures. Ascertaining theabsolute configuration (AC) of natural products is pivotal for attributing their specific biological signature. Specific rotation data commonly characterize chiral non-racemic natural products; however, measurement conditions, viz., solvent and concentration, can influence the sign of specific rotation values, especially when characterizing natural products possessing small values. For example, licochalcone L, a minor constituent of Glycyrrhiza inflata, was reported with a specific rotation of [α]D22= +13 (c 0.1, CHCl3); however, not establishing the AC and the reported zero specific rotation for an identical compound, licochalcone AF1, resulted in debatable chirality and its biogenesis. In this study, a combined experimental and computational chiroptical approach involving specific rotation and electronic circular dichroism (ECD) data, supported by time-dependent density functional theory (TDDFT), were effectively utilized to establish the AC of licochalcone L as the (E, 2″S)-isomer. Establishing the 2″S absolute configuration permitted the conception of a reasonable biosynthetic pathway involving intramolecular '5-exo-tet' ring opening of a chiral oxirane to form chiral licochalcone L in G. inflata.


Assuntos
Produtos Biológicos , Dicroísmo Circular , Estereoisomerismo
18.
Chem Res Toxicol ; 36(5): 747-756, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37042673

RESUMO

Structurally similar phytochemical compounds may elicit markedly different skin sensitization responses. Eugenol and isoeugenol are natural phenylpropanoids found in various essential oils are frequently used as fragrance ingredients in consumer products due to their pleasing aromatic properties. Both compounds are also skin sensitizers with isoeugenol being a stronger sensitizer than eugenol. The most commonly accepted mechanisms for haptenation by eugenol involve formation of a quinone methide or an ortho-quinone intermediate. The mechanism for the increased skin response to isoeugenol remains elusive, although quinone methide intermediates have been proposed. The recent identification of diastereomeric 7,4'-oxyneolignans as electrophilic, thiol-depleting isoeugenol derivatives has revived interest in the possible role of elusive reactive intermediates associated with the isoeugenol's haptenation process. In the present work, integrated non-animal skin sensitization methods were performed to determine the ability of syn-7,4'-oxyneolignan to promote haptenation and activation of further molecular pathways in keratinocytes and dendritic cells, confirming it as a candidate skin sensitizer. Kinetic NMR spectroscopic studies using dansyl cysteamine (DCYA) confirmed the first ordered nature of the nucleophilic addition for the syn-7,4'-oxyneolignan. Computational studies reaffirmed the "syn" stereochemistry of the isolated 7,4'-oxyneolignans along with that of their corresponding DCYA adducts and provided evidence for the preferential stereoselectivity. A plausible rationale for isoeugenol's strong skin sensitization is proposed based on the formation of a hydroxy quinone methide as a reactive intermediate rather than the previously assumed quinone methide.


Assuntos
Eugenol , Indolquinonas , Pele/metabolismo
19.
Foods ; 12(7)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37048333

RESUMO

Morphine and codeine are the two principal opiates found in the opium poppy (Papaver somniferum L.) and are therapeutically used for pain management. Poppy seeds with low opiates are primarily used for culinary purposes due to their nutritional and sensory attributes. Intentional adulteration of poppy seeds is common, often combined with immature, less expensive, exhausted, or substituted with morphologically similar seeds, viz., amaranth, quinoa, and sesame. For a safer food supply chain, preventive measures must be implemented to mitigate contamination or adulteration. Moreover, the simultaneous analysis of P. somniferum and its adulterants is largely unknown. Pre- and post-processing further complicate the alkaloid content and may pose a significant health hazard. To address these issues, two independent methods were investigated with eight botanically verified and fifteen commercial samples. Microscopical features were established for the authenticity of raw poppy seeds. Morphine, codeine, and thebaine quantities ranged from 0.8-223, 0.2-386, and 0.1-176 mg/kg, respectively, using LC-QToF. In most cases, conventional opiates have a higher content than papaverine and noscapine. The analytical methodology provided a chemical profile of 47 compounds that can be effectively applied to distinguish poppy seeds from their adulterants and may serve as an effective tool to combat ongoing adulteration.

20.
Molecules ; 28(7)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37049909

RESUMO

Elderberry is highly reputed for its health-improving effects. Multiple pieces of evidence indicate that the consumption of berries is linked to enhancing human health and preventing or delaying the onset of chronic medical conditions. Compared with other fruit, elderberry is a very rich source of anthocyanins (approximately 80% of the polyphenol content). These polyphenols are the principals that essentially contribute to the high antioxidant and anti-inflammatory capacities and the health benefits of elderberry fruit extract. These health effects include attenuation of cardiovascular, neurodegenerative, and inflammatory disorders, as well as anti-diabetic, anticancer, antiviral, and immuno-stimulatory effects. Sales of elderberry supplements skyrocketed to $320 million over the year 2020, according to an American Botanical Council (ABC) report, which is attributable to the purported immune-enhancing effects of elderberry. In the current review, the chemical composition of the polyphenolic content of the European elderberry (Sambucus nigra) and the American elderberry (Sambucus canadensis), as well as the analytical techniques employed to analyze, characterize, and ascertain the chemical consistency will be addressed. Further, the factors that influence the consistency of the polyphenolic chemical composition, and hence, the consistency of the health benefits of elderberry extracts will be presented. Additionally, adulteration and safety as factors contributing to consistency will be covered. The role of elderberry in enhancing human health alone with the pharmacological basis, the cellular pathways, and the molecular mechanisms underlying the observed health benefits of elderberry fruit extracts will be also reviewed.


Assuntos
Sambucus , Humanos , Sambucus/química , Antocianinas/química , Extratos Vegetais/química , Polifenóis/química , Estresse Oxidativo , Inflamação/tratamento farmacológico , Frutas/química
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