Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
Mais filtros








Intervalo de ano de publicação
1.
Int J Mol Sci ; 25(17)2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39273596

RESUMO

Staphylococcus aureus infections present a significant threat to the global healthcare system. The increasing resistance to existing antibiotics and their limited efficacy underscores the urgent need to identify new antibacterial agents with low toxicity to effectively combat various S. aureus infections. Hence, in this study, we have screened T-muurolol for possible interactions with several S. aureus-specific bacterial proteins to establish its potential as an alternative antibacterial agent. Based on its binding affinity and interactions with amino acids, T-muurolol was identified as a potential inhibitor of S. aureus lipase, dihydrofolate reductase, penicillin-binding protein 2a, D-Ala:D-Ala ligase, and ribosome protection proteins tetracycline resistance determinant (RPP TetM), which indicates its potentiality against S. aureus and its multi-drug-resistant strains. Also, T-muurolol exhibited good antioxidant and anti-inflammatory activity by showing strong binding interactions with flavin adenine dinucleotide (FAD)-dependent nicotinamide adenine dinucleotide phosphate (NAD(P)H) oxidase, and cyclooxygenase-2. Consequently, molecular dynamics (MD) simulation and recalculating binding free energies elucidated its binding interaction stability with targeted proteins. Furthermore, quantum chemical structure analysis based on density functional theory (DFT) depicted a higher energy gap between the highest occupied molecular orbital and lowest unoccupied molecular orbital (EHOMO-LUMO) with a lower chemical potential index, and moderate electrophilicity suggests its chemical hardness and stability and less polarizability and reactivity. Additionally, pharmacological parameters based on ADMET, Lipinski's rules, and bioactivity score validated it as a promising drug candidate with high activity toward ion channel modulators, nuclear receptor ligands, and enzyme inhibitors. In conclusion, the current findings suggest T-muurolol as a promising alternative antibacterial agent that might be a potential phytochemical-based drug against S. aureus. This study also suggests further clinical research before human application.


Assuntos
Antibacterianos , Descoberta de Drogas , Compostos Fitoquímicos , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química , Descoberta de Drogas/métodos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Simulação por Computador , Humanos , Antioxidantes/farmacologia , Antioxidantes/química
2.
Plants (Basel) ; 13(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38891245

RESUMO

Diabetes mellitus (DM) is a global health concern characterized by a deficiency in insulin production. Considering the systemic toxicity and limited efficacy associated with current antidiabetic medications, there is the utmost need for natural, plant-based alternatives. Herbal medicines have experienced exponential growth in popularity globally in recent years for their natural origins and minimal side effects. Ecuador has a rich cultural history in ethnobotany that plays a crucial role in its people's lives. This study identifies 27 Ecuadorian medicinal plants that are traditionally used for diabetes treatment and are prepared through infusion, decoction, or juice, or are ingested in their raw forms. Among them, 22 plants have demonstrated hypoglycemic or anti-hyperglycemic properties that are rich with bioactive phytochemicals, which was confirmed in several in vitro and in vivo studies. However, Bryophyllum gastonis-bonnieri, Costus villosissimus, Juglans neotropica, Pithecellobium excelsum, and Myroxylon peruiferum, which were extensively used in traditional medicine preparation in Ecuador for many decades to treat diabetes, are lacking in pharmacological elucidation. The Ecuadorian medicinal plants used to treat diabetes have been found to have several bioactive compounds such as flavonoids, phenolics, fatty acids, aldehydes, and terpenoids that are mainly responsible for reducing blood sugar levels and oxidative stress, regulating intestinal function, improving insulin resistance, inhibiting α-amylase and α-glucosidase, lowering gluconeogenic enzymes, stimulating glucose uptake mechanisms, and playing an important role in glucose and lipid metabolism. However, there is a substantial lack of integrated approaches between the existing ethnomedicinal practices and pharmacological research. Therefore, this review aims to discuss and explore the traditional medicinal plants used in Ecuador for treating DM and their bioactive phytochemicals, which are mainly responsible for their antidiabetic properties. We believe that the use of Ecuadorian herbal medicine in a scientifically sound way can substantially benefit the local economy and industries seeking natural products.

3.
Sci Rep ; 14(1): 5608, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454146

RESUMO

Essential oil from Thymus vulgaris L. has valuable therapeutic potential that is highly desired in pharmaceutical, food, and cosmetic industries. Considering these advantages and the rising market demand, induced polyploids were obtained using oryzalin to enhance essential oil yield. However, their therapeutic values were unexplored. So, this study aims to assess the phytochemical content, and antimicrobial, antioxidant, and anti-inflammatory activities of tetraploid and diploid thyme essential oils. Induced tetraploids had 41.11% higher essential oil yield with enhanced thymol and γ-terpinene content than diploid. Tetraploids exhibited higher antibacterial activity against all tested microorganisms. Similarly, in DPPH radical scavenging assay tetraploid essential oil was more potent with half-maximal inhibitory doses (IC50) of 180.03 µg/mL (40.05 µg TE/mg) than diploid with IC50 > 512 µg/mL (12.68 µg TE/mg). Tetraploids exhibited more effective inhibition of in vitro catalytic activity of pro-inflammatory enzyme cyclooxygenase-2 (COX-2) than diploids at 50 µg/mL concentration. Furthermore, molecular docking revealed higher binding affinity of thymol and γ-terpinene towards tested protein receptors, which explained enhanced bioactivity of tetraploid essential oil. In conclusion, these results suggest that synthetic polyploidization using oryzalin could effectively enhance the quality and quantity of secondary metabolites and can develop more efficient essential oil-based commercial products using this induced genotype.


Assuntos
Monoterpenos Cicloexânicos , Dinitrobenzenos , Óleos Voláteis , Óleos de Plantas , Sulfanilamidas , Thymus (Planta) , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Timol/farmacologia , Thymus (Planta)/química , Tetraploidia , Simulação de Acoplamento Molecular , Compostos Fitoquímicos/farmacologia
4.
Front Plant Sci ; 14: 1332428, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38155852

RESUMO

Melissa officinalis L., a well-known herb with diverse industrial and ethnopharmacological properties. Although, there has been a significant lack in the breeding attempts of this invaluable herb. This study aimed to enhance the agronomical traits of M. officinalis through in vitro polyploidization. Nodal segments were micropropagated and subjected to oryzalin treatment at concentrations of 20, 40, and 60 mM for 24 and 48 hours. Flow cytometry, chromosome counting, and stomatal characteristics were employed to confirm the ploidy level of the surviving plants. The survival rate of the treated explants decreased exponentially with increasing oryzalin concentration and duration. The highest polyploid induction rate (8%) was achieved with 40 mM oryzalin treatment for 24 hours. The induced tetraploid plants exhibited vigorous growth, characterized by longer shoots, larger leaves, and a higher leaf count. Chlorophyll content and fluorescence parameters elucidated disparities in photosynthetic performance between diploid and tetraploid genotypes. Tetraploid plants demonstrated a 75% increase in average essential oil yield, attributed to the significantly larger size of peltate trichomes. Analysis of essential oil composition in diploid and tetraploid plants indicated the presence of three major components: geranial, neral, and citronellal. While citronellal remained consistent, geranial and neral increased by 11.06% and 9.49%, respectively, in the tetraploid population. This effective methodology, utilizing oryzalin as an anti-mitotic agent for polyploid induction in M. officinalis, resulted in a polyploid genotype with superior morpho-physiological traits. The polyploid lemon balm generated through this method has the potential to meet commercial demands and contribute significantly to the improvement of lemon balm cultivation.

5.
Heliyon ; 9(12): e22480, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38107328

RESUMO

Essential oils (EOs) from Indian spices like Elettaria cardamomum (L.) Maton (small green cardamom), Syzygium aromaticum (L.) Merr. & L.M. Perry (clove), Cinnamomum zeylanicum Blume (cinnamon quills), and Cinnamomum tamala (Buch.-Ham.) T. Nees & C. H. Eberm (Indian bay leaves) exhibit a broad spectrum range of biological activity including antibacterial and antifungal activity. Yet, there is a lack of data regarding the antimicrobial activity of their formulations. Also, the link between the antimicrobial effect of individual EO with their chemical composition and molecular interaction with bacterial pathogens has not been systematically explored. Therefore, the objectives of the current study were to evaluate the antimicrobial activity and phytochemical characterization of EOs and to bridge the gap between them through in-silico molecular interactions. The antibacterial activity of EOs of four different spices and their formulations against foodborne pathogens such as Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa was evaluated using the disc volatilization method. The chemical profile of the individual EO was determined through GC-MS analysis and molecular interactions of identified major components with bacterial proteins were carried out through molecular docking studies. All EOs and their formulations exhibited antibacterial activity ranging from 5.92 to 24.55 mm and 11-23.52 mm, respectively. Among all EOs, cinnamon and formulation C (cardamom: cinnamon- 2:1) exhibited the highest antibacterial activity. The composition of the EOs included sesquiterpenes, monoterpenoids, monoterpenes, and, phenylpropanoids such as (E)-cinnamaldehyde, δ-cadinene, α-copaene, eugenol, caryophyllene, eugenol acetate, methyl eugenol, menthadiene, eucalyptol, α-terpinyl acetate, and sabinene. Furthermore, docking study revealed that the abundant compounds from cinnamon EO mainly α-copaene and δ-cadinene had a high binding affinity towards the bacterial essential proteins which increases the bacterial susceptibility towards cinnamon EO. The selected EOs and their formulations were systematically analysed and they were effective against foodborne pathogens. The current findings suggest the application of these EOs against food pathogens with further research.

6.
Front Plant Sci ; 14: 1248978, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38034577

RESUMO

Grapevines are economically important woody perennial crops widely cultivated for their fruits that are used for making wine, grape juice, raisins, and table grapes. However, grapevine production is constantly facing challenges due to climate change and the prevalence of pests and diseases, causing yield reduction, lower fruit quality, and financial losses. To ease the burden, continuous crop improvement to develop superior grape genotypes with desirable traits is imperative. Polyploidization has emerged as a promising tool to generate genotypes with novel genetic combinations that can confer desirable traits such as enhanced organ size, improved fruit quality, and increased resistance to both biotic and abiotic stresses. While previous studies have shown high polyploid induction rates in Vitis spp., rigorous screening of genotypes among the produced polyploids to identify those exhibiting desired traits remains a major bottleneck. In this perspective, we propose the integration of the genomic selection approach with omics data to predict genotypes with desirable traits among the vast unique individuals generated through polyploidization. This integrated approach can be a powerful tool for accelerating the breeding of grapevines to develop novel and improved grapevine varieties.

7.
Bol. latinoam. Caribe plantas med. aromát ; 22(4): 417-430, jul. 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1556221

RESUMO

The present study aimed to document the traditional use of medicinal plants used to treat Diabetes mellitus Type II in Bolivia. Based on the scientific literature were identified 35 medicinal plant species distributed in 21 botanical families, of which 52 % are native to Bolivia and 48 % are introduced. The botanical families with the highest representation of species were Asteraceae (7 species, 19%) and Fabaceae (17%). The most frequented growth forms were herbs (34%) and trees (29%). Leaves (30%) were the most frequently used plant parts, followed by roots (14%), and bark (9%), mostly prepared as an infusion (40%) and decoction (33%). From the available scientific studies, 25 medicinal species were verified for their antidiabetic properties with positive results, but it is necessary provide more biochemical and clinical analysis of medicinal plants to make better use of their potential.


El objetivo del presente estudio fue documentar el uso tradicional de plantas medicinales para el tratamiento de la Diabetes mellitus tipo II en Bolivia. Con base en la literatura científica se identificaron 35 especies medicinales, distribuidas en 21 familias botánicas, de las cuales el 52% son nativas de Bolivia y el 48% son introducidas. Las familias botánicas con mayor representación de especies fueron Asteraceae (7 especies, 19%) y Fabaceae (17%). Las formas de crecimiento más frecuentes fueron hierbas (34%) y árboles (29%). Las hojas (30%) fueron la parte de la planta más utilizada, seguidas de las raíces (14%) y la corteza (9%), preparadas especialmente como infusión (40%) y decocción (33%). Así mismo, con base en estudios científicos disponibles, se confirmó la actividad antidiabética de 25 especies medicinales. Sin embargo, es necesario aportar más análisis bioquímicos y clínicos de las plantas medicinales para aprovechar mejor su potencial.


Assuntos
Plantas Medicinais/química , Diabetes Mellitus/prevenção & controle , Medicina Tradicional , Bolívia , Etnobotânica , Diabetes Mellitus/tratamento farmacológico
8.
Plants (Basel) ; 12(3)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36771553

RESUMO

Melissa officinalis L. is well known for its lemon-scented aroma and various pharmacological properties. Despite these valuable properties, the genes involved in the biosynthetic pathways in M. officinalis are not yet well-explored when compared to other members of the mint family. For that, gene expression studies using quantitative real-time PCR (qRT-PCR) are an excellent tool. Although qRT-PCR can provide accurate results, its accuracy is highly reliant on the expression and stability of the reference gene used for normalization. Hence, selecting a suitable experiment-specific reference gene is very crucial to obtain accurate results. However, to date, there are no reports for experiment-specific reference genes in M. officinalis. Therefore, in the current study, ten commonly used reference genes were assessed for their suitability as optimal reference genes in M. officinalis under various abiotic stress conditions and different plant organs. The candidate genes were ranked based on BestKeeper, comparative ΔCt, geNorm, NormFinder, and RefFinder. Based on the results, we recommend the combination of EF-1α and GAPDH as the best reference genes to normalize gene expression studies in M. officinalis. On the contrary, HLH71 was identified as the least-performing gene. Thereafter, the reliability of the optimal gene combination was assessed by evaluating the relative gene expression of the phenylalanine ammonia lyase (PAL) gene under two elicitor treatments (gibberellic acid and jasmonic acid). PAL is a crucial gene involved directly or indirectly in the production of various economically important secondary metabolites in plants. Suitable reference genes for each experimental condition are also discussed. The findings of the current study form a basis for current and future gene expression studies in M. officinalis and other related species.

9.
Plants (Basel) ; 11(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36365331

RESUMO

Salvia rosmarinus L. (rosemary) is known to have a wide range of pharmacological effects including antidiabetic, anticarcinogenic, and antitumorigenic properties owing to its secondary metabolites. Studies aiming to elevate these metabolites have utilized various elicitors and stresses under in vitro conditions, although underlying molecular mechanisms remain unexplored. Gene expression studies using RT-qPCR might provide valuable information regarding how plant and plant cells interact and perceive various treatments and elicitors. However, despite being able to calculate accurate fold changes, the accuracy of the RT-qPCR data highly depends on the expression of reference genes. To the best of our knowledge, there is no information available on the stable reference genes in rosemary under in vitro conditions. Thus, in this paper, we assessed the stability of seven commonly used reference genes under different elicitor and stress conditions using RT-qPCR. Thereafter, the five most commonly used software and algorithms (comparative ΔCt, BestKeeper, NormFinder, geNorm, and RefFinder) were used to rank the candidates based on their expression stabilities. In conclusion, we recommend using a combination of F1-ATPase, ATP synthase and ACCase to normalize the gene expression experiments in rosemary under in vitro conditions. The selected reference genes were verified using 4-coumarate-CoA ligase, a pharmacologically important gene, whose expression might alter under nanoparticle treatment. Additionally, reference genes for several plant tissues, elicitors, and stresses are also proposed. The conclusions obtained from this current study will accelerate the future molecular work in S. rosmarinus and other related species.

10.
Front Pharmacol ; 12: 740302, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34744723

RESUMO

This commentary critically examines the modern paradigm of natural volatiles in 'medical aromatherapy', first by explaining the semantics of natural volatiles in health, then by addressing chemophenetic challenges to authenticity or reproducibility, and finally by elaborating on pharmacokinetic and pharmacodynamic processes in food, therapy, and disease prophylaxis. Research over the last 50 years has generated substantial knowledge of the chemical diversity of volatiles, and their strengths and weaknesses as antimicrobial agents. However, due to modest in vitro outcomes, the emphasis has shifted toward the ability to synergise or potentiate non-volatile natural or pharmaceutical drugs, and to modulate gene expression by binding to the lipophilic domain of mammalian cell receptors. Because essential oils and natural volatiles are small and lipophilic, they demonstrate high skin penetrating abilities when suitably encapsulated, or if derived from a dietary item they bioaccumulate in fatty tissues in the body. In the skin or body, they may synergise or drive de novo therapeutic outcomes that range from anti-inflammatory effects through to insulin sensitisation, dermal rejuvenation, keratinocyte migration, upregulation of hair follicle bulb stem cells or complementation of anti-cancer therapies. Taking all this into consideration, volatile organic compounds should be examined as candidates for prophylaxis of cardiovascular disease. Considering the modern understanding of biology, the science of natural volatiles may need to be revisited in the context of health and nutrition.

11.
Phytother Res ; 35(11): 6359-6368, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34585449

RESUMO

Male infertility refers to the inability to conceive a natural pregnancy in a fertile female, and approximately 15% of reproductive-aged couples worldwide face this problem. Several plants were used to treat fertility disorders and, among them, Lepidium meyenii, a folk medicament of Andean regions, is still used to enhance vitality and treat sterility in humans and domestic animals. The aim of the study was to evaluate the effects of L. meyenii Walpers on infertile patients by a randomized, double-blind, placebo-controlled trial. Fifty patients suffering from various reproductive-related problems were enrolled for 16 weeks to evaluate the effect of yellow maca on semen quality and serum hormone levels. Treatment with maca improved the percentage of sperm concentration by 40%, whereas the placebo improved by 76% after 8 and 16 weeks of treatment, but the results were statistically non-significant. No statistically significant change in hormone levels was reported by using maca, except a decrease in the level of free testosterone. Results are not sufficient to assess the efficacy of maca on male fertility. Further investigation and trials are required to obtain conclusive results.


Assuntos
Infertilidade Masculina , Lepidium , Adulto , Animais , Humanos , Infertilidade Masculina/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Análise do Sêmen , Contagem de Espermatozoides , Testosterona
12.
Bol. latinoam. Caribe plantas med. aromát ; 20(5): 482-495, sept. 2021. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1368643

RESUMO

Semi-structured interviews (80) were applied in order to document the medicinal plants used by the Pijao indigenous community in Natagaima, Colombia. As a result, a total of 110 species distributed in 54 families were registered, Asteraceae and Fabaceae (9% each) being the most important families. Regarding the parts of the plant, the most used structure was leaves (46.7%), the main form of preparation was infusion (32%), and the most used way of administration was oral (77.8%). The value of use of the species by informants (VUis), therelative importance of medicinal species (IRE) and the index of cultural value of medicinal species (IVUs) were determined. The most important species according to their value of use were: Tamarindus indicaL., Psidium guajavaL., Menthax piperitaL., Moringa oleiferaLam. The most reported ailments were gastrointestinal problems such as stomach pain and diarrhea, general aches, headache, fever, swollen liver, and respiratory problems.


Entrevistas semiestructuradas (80) fueron aplicadas con el fin de documentar las plantas medicinales utilizadas por la comunidad indígena Pijao en Natagaima, Colombia. Como resultado seregistraron un total de 110 especies distribuidas en 54 familias, siendo Asteráceas y Fabáceas (9% cada una) las más importantes. El órgano más utilizado fueron las hojas (46.7%). La forma de preparación principal fue la infusión (32%), y la vía de administración más utilizada fue la oral (77.8%). Se determinó el valor de uso de la especie por informante (VUis), importancia relativa de especies medicinales (IRE) y el índice de valor cultural de especies medicinales (IVUs). Las especies más importantes según el valor de uso fueron: Tamarindus indicaL., Psidium guajavaL., Menthax piperitaL. Moringa oleifera Lam. Las afecciones mayormente registradas fueron los problemas gastrointestinales, tales como dolor de estómago y diarrea; dolores corporales generales, dolor de cabeza, fiebre, hígado inflamado y problemas respiratorios.


Assuntos
Humanos , Plantas Medicinais , Etnobotânica , Medicina Tradicional , Inquéritos e Questionários , Colômbia
13.
Antibiotics (Basel) ; 10(8)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34438987

RESUMO

Vitex doniana Sweet is an African medicinal species that is prescribed as an aqueous bark extract to be applied topically or orally to achieve anti-infective outcomes. In select regions it is also taken orally as an antimalarial agent. The aim of the current study was to explore the biological properties of V. doniana and isolated compounds in the context of pathogenic bacteria and the protozoan parasite Plasmodium falciparum. Three compounds were isolated and assigned by nuclear magnetic resonance spectroscopy as ecdysteroids: (1) 20-hydroxyecdysone, (2) turkesterone, and (3) ajugasterone C. Interestingly, two of these compounds had not previously been identified in V. doniana, providing evidence of chemical variability between regions. The bark extract and three ecdysteroids were screened for activity against a panel of pathogenic bacteria associated with skin, stomach and urinary tract infections, and the protozoan parasite P. falciparum. The crude extract of the bark inhibited all bacterial strains with MIC values of 125-250 µg.mL-1. The three isolated compounds demonstrated less activity with MIC values of 500-1000 µg.mL-1. Furthermore, no activity was observed against P. falciparum at the screening concentration of 4.8 µg.mL-1. Nevertheless, we present a hypothesis for the possible mechanism for symptomatic relief of malarial fever, which may involve reduction of prostaglandin E(1) & E(2) activity in the hypothalamus via modulation of the monoaminergic system. While further studies are required to identify all antimicrobial agents within this plant species and to determine the cytotoxicity of each of these compounds, these data suggest that the traditional application of this species as an antiseptic is valid.

14.
Plants (Basel) ; 10(4)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923613

RESUMO

Australia's endemic desert shrubs are commonly aromatic, with chemically diverse terpenes and phenylpropanoids in their headspace profiles. Species from the genus Eremophila (Scrophulariaceae ex. Myoporaceae) are the most common, with 215 recognised taxa and many more that have not yet been described, widely spread across the arid parts of the Australian continent. Over the years, our research team has collected multiple specimens as part of a survey to investigate the chemical diversity of the genus and create leads for further scientific enquiry. In the current study, the diversity of volatile compounds is studied using hydrodistilled essential oils and leaf solvent extracts from 30 taxa. Several rare terpenes and iridoids were detected in chemical profiles widely across the genus, and three previously undescribed sesquiterpenes were isolated and are assigned by 2D NMR-E-11(12)-dehydroisodendrolasin, Z-11-hydroxyisodendrolasin and 10-hydroxydihydro-α-humulene acetate. Multiple sampling from Eremophila longifolia, Eremophila arbuscular, Eremophila latrobei, Eremophila deserti, Eremophila sturtii, Eremophila oppositifolia and Eremophila alternifolia coneys that species in Eremophila are highly chemovariable. However, taxa are generally grouped according to the expression of (1) furanosesquiterpenes, (2) iridoids or oxides, (3) mixtures of 1 and 2, (4) phenylpropanoids, (5) non-furanoid terpenes, (6) mixtures of 4 and 5, and less commonly (7) mixtures of 1 and 5. Furthermore, GC-MS analysis of solvent-extracted leaves taken from cultivated specimens conveys that many heavier 'volatiles' with lower vapour pressure are not detected in hydrodistilled essential oils and have therefore been neglected in past chemical studies. Hence, our data reiterate that chemical studies of the genus Eremophila will continue to describe new metabolites and that taxon determination has limited predictive value for the chemical composition.

15.
Plants (Basel) ; 9(11)2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33202983

RESUMO

The highly aromatic Australian mint bushes from the genus Prostanthera Labill. produce a high yield of essential oil on hydrodistillation. Together with its rich history, horticultural potential, iconic flowers, and aromatic leaves, it achieves high ornamental and culinary value. Species in the genus express highly diverse and chemically unique essential oils that demonstrate intra- and inter-specific patterns that have inspired taxonomic reinterpretation for over a hundred years. Previous studies have conveyed that phenoplastic expression of volatiles creates chemotypes within taxa, adding complexity to chemophenetic exploration. The current study chemically characterised essential oils from 64 highly aromatic specimens, representative of 25 taxa, giving yields as high as >2% g/g. The chemical profiles of essential oils are diverse, but generally include 1,8-cineole and signatory compounds such as sesquiterpene oxides, caryophyllene oxide, kessane and cis-dihydroagarofuran; sesquiterpene alcohols, globulol, epiglobulol, maaliol, prostantherol, spathulenol and ledol; and monoterpene derivatives of common scaffolds, borneol, bornyl acetate, bornanone, linalool and linalyl acetate. As in previous studies, analysis of chemical data confirms that the chemistry strongly agrees with taxonomic classifications. Importantly, as in classical taxonomy, the current chemical study complemented morphological analysis but conveys chemovariation, obscuring the taxonomic agreement. Nevertheless, variation within taxa may be due to environmental factors, meaning that cultivation of species in gardens will create different chemical profiles as compared to those published here.

16.
Metabolites ; 10(10)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33066019

RESUMO

Smallanthus sonchifolius (yacon) is an edible tuberous Andean shrub that has been included in the diet of indigenous people since before recorded history. The nutraceutical and medicinal properties of yacon are widely recognized, especially for the improvement of hyperglycemic disorders. However, the chemical diversity of the main bioactive series of caffeic acid esters has not been explored in detail. In this metabolomics study, we applied the latest tools to facilitate the targeted isolation of new caffeic acid esters. Using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), we analyzed extracts from different organs (roots, vascular tissues of the stems, stem epidermis, leaves, bracts, and ray flowers) and followed a feature-based molecular networking approach to characterize the structural diversity of caffeic acid esters and recognize new compounds. The analysis identified three potentially new metabolites, one of them confirmed by isolation and full spectroscopic/spectrometric assignment using nuclear magnetic resonance (NMR), high-resolution mass spectrometry (HRMS), and MS/MS. This metabolite (5-O-caffeoyl-2,7-anhydro-d-glycero-ß-d-galacto-oct-2-ulopyranosonic acid), along with eight known caffeic acid esters, was isolated from the roots and stems. Furthermore, based on detailed tandem MS analyses, we suggest that the two isomeric monocaffeoyl-2,7-anhydro-2-octulopyranosonic acids found in yacon can be reliably distinguished based on their characteristic MS2 and MS3 spectra. The outcome of the current study confirms the utility of feature-based molecular networking as a tool for targeted isolation of previously undescribed metabolites and reveals the full diversity of potentially bioactive metabolites from S. sonchifolius.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA