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1.
Proc Natl Acad Sci U S A ; 121(7): e2318586121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38319969

RESUMO

Monoterpene indole alkaloids (MIAs) are a large and diverse class of plant natural products, and their biosynthetic construction has been a subject of intensive study for many years. The enzymatic basis for the production of aspidosperma and iboga alkaloids, which are produced exclusively by members of the Apocynaceae plant family, has recently been discovered. Three carboxylesterase (CXE)-like enzymes from Catharanthus roseus and Tabernanthe iboga catalyze regio- and enantiodivergent [4+2] cycloaddition reactions to generate the aspidosperma (tabersonine synthase, TS) and iboga (coronaridine synthase, CorS; catharanthine synthase, CS) scaffolds from a common biosynthetic intermediate. Here, we use a combined phylogenetic and biochemical approach to investigate the evolution and functional diversification of these cyclase enzymes. Through ancestral sequence reconstruction, we provide evidence for initial evolution of TS from an ancestral CXE followed by emergence of CorS in two separate lineages, leading in turn to CS exclusively in the Catharanthus genus. This progression from aspidosperma to iboga alkaloid biosynthesis is consistent with the chemotaxonomic distribution of these MIAs. We subsequently generate and test a panel of chimeras based on the ancestral cyclases to probe the molecular basis for differential cyclization activity. Finally, we show through partial heterologous reconstitution of tabersonine biosynthesis using non-pathway enzymes how aspidosperma alkaloids could have first appeared as "underground metabolites" via recruitment of promiscuous enzymes from common protein families. Our results provide insight into the evolution of biosynthetic enzymes and how new secondary metabolic pathways can emerge through small but important sequence changes following co-option of preexisting enzymatic functions.


Assuntos
Aspidosperma , Catharanthus , Alcaloides de Triptamina e Secologanina , Tabernaemontana , Tabernaemontana/metabolismo , Aspidosperma/metabolismo , Carboxilesterase/metabolismo , Filogenia , Alcaloides Indólicos/metabolismo , Alcaloides de Triptamina e Secologanina/química , Alcaloides de Triptamina e Secologanina/metabolismo , Plantas/metabolismo , Catharanthus/metabolismo
2.
Int J Environ Health Res ; 34(2): 1088-1099, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37015007

RESUMO

The goal of this study was to determine for the first time the polyphenol content, antioxidant, and gastroprotective properties of the roots and leaves of Reichardia picroides. TPC considerably varied as a function of organs and solvent nature and ranged from 50 to 284.80 mg GAE/g DW. Leaves exhibited the highest amount of phenolics by using acetone 70%, the same tendency was observed for antioxidant activity. Besides, in vivo gastro-protective effects following HCl/EtOH-induced ulcer models displayed that roots extract at a high dose (500 mg) seemed to be the best performing extract with a decrease of ulceration index (UI) and an increase in the percentage of protection (PP), SOD, CAT, and GPX activities. All these data have been proved with principal component analysis (PCA). Overall, the results indicated that R. picroides could be considered a valuable source of natural compounds, which are beneficial for human health.


Assuntos
Antiulcerosos , Úlcera Gástrica , Tabernaemontana , Humanos , Ratos , Animais , Antioxidantes/uso terapêutico , Antioxidantes/toxicidade , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/prevenção & controle , Etanol/toxicidade , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Antiulcerosos/uso terapêutico , Antiulcerosos/toxicidade
3.
Molecules ; 28(18)2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37764440

RESUMO

Phytochemical investigation of the two Tabernaemontana species (Apocynaceae) T. peduncularis Wall. and T. divaricata (L.) R.Br. ex Roem. & Schult. indicated closely related biosynthetic pathways leading to lipophilic and hydrophilic alkaloids. In total, 18 specialized metabolites comprising indole-derived alkaloid aglycones, three oxindole-derived alkaloid glycosides, and two iridoid glucosides could be identified in the studied species. Among the alkaloids, the two Iboga-type alkaloids 3,7-coronaridine isoindolenine, coronaridine 3,4-iminium and a javaniside derivative bearing a glucuronic acid, named javanuronic acid, could be described by spectroscopic and spectrometric methods for the first time. A docking experiment using alpha-fold was performed to generate a protein model of the enzyme 7-deoxyloganetic acid glucosyl transferase. Performed bioassays exhibited a growth reduction of neonate Spodoptera littoralis larvae and reduced cell viability of HepG2 cells of the extracts containing Iboga alkaloids, whilst the javaniside derivatives containing hydrophilic fraction did not show any effects. These findings indicate a high flexibility in the formation of bioactive indole alkaloid aglycones by Tabernaemontana species and also evidence similar accumulation trends in both species as well as indicate that biosynthetic routes leading to oxindole alkaloids like javanisides are more widespread than reported. Furthermore, the incorporation of the three novel compounds into potential biosynthetic pathways is discussed.


Assuntos
Tabernaemontana , Humanos , Recém-Nascido , Oxindóis , Glucuronídeos , Vias Biossintéticas
4.
Fitoterapia ; 169: 105602, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37423501

RESUMO

Tabernaemontana arborea (Apocynaceae) is a Mexican tree species known to contain ibogan type alkaloids. This study aimed at determining central nervous system-related activities of an alkaloid extract obtained from the root bark of T. arborea. A gas chromatography-mass spectrometry (GC-MS) analysis was performed to describe the alkaloid profile of the extract. A wide dosing range (0.1 to 56.2 mg/kg) of this extract was evaluated in different murine models. Electrical brain activity was examined by electroencephalography (EEG). The extract's effects on motor coordination, ambulatory activity, and memory were analyzed based on the rotarod, open field (OFT), and object recognition tests (ORT), respectively. Antidepressant and antinociceptive activities were determined using the forced swimming test (FST) and the formalin assay, respectively. In order to elucidate the underlying mechanisms of action, the 5-HT1A receptor antagonist WAY100635 (1 mg/kg) or the opioid receptor antagonist naloxone (1 mg/kg) was included in the latter experiments. GC-MS analysis (µg/mg extract) confirmed the presence of the monoterpenoid indole alkaloids (MIAs) voacangine (207.00), ibogaine (106.33), vobasine (72.81), coronaridine (30.72), and ibogamine (24.2) as principal constituents of the extract, which exhibited dose- and receptor-dependent antidepressant (0.1 to 1 mg/kg; 5-HT1A) and antinociceptive (30 and 56.2 mg/kg; opioid) effects, without altering motor coordination, ambulatory activity, and memory. EEG indicated CNS depressant activity at high doses (30 and 56.2 mg/kg). The root bark of T. arborea contains a mixture of alkaloids that may hold therapeutic value in pain relief and the treatment of psychiatric diseases without causing neurotoxic activity at effective doses.


Assuntos
Antineoplásicos , Alcaloides de Triptamina e Secologanina , Tabernaemontana , Animais , Camundongos , Tabernaemontana/química , Modelos Animais de Doenças , Estrutura Molecular , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Sistema Nervoso Central , Analgésicos/farmacologia , Transmissão Sináptica
5.
Fitoterapia ; 169: 105588, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37336417

RESUMO

Seventeen undescribed Aspidosperma-type alkaloids (ASPs), along with nine known ones were isolated from the leaves of Tabernaemontana bovina. Taberbovermines A and B were assigned to tabersonine-type with a contracted A- and E-ring, respectively. Taberbovermine C was attributed to tabersonine without D ring. These structures of the ASPs were established on the basis of comprehensive spectroscopic data, electronic circular dichroism calculations and X-ray diffraction. The summaries of structure-activity relationship of tabersonine class were discussed based on hepatoma cells screening.


Assuntos
Alcaloides , Aspidosperma , Tabernaemontana , Tabernaemontana/química , Aspidosperma/química , Estrutura Molecular , Alcaloides/química , Alcaloides Indólicos/química , Folhas de Planta/química
6.
J Nat Prod ; 86(6): 1500-1511, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37221656

RESUMO

The iboga alkaloids scaffold shows great potential as a pharmacophore in drug candidates for the treatment of neuropsychiatric disorders. Thus, the study of the reactivity of this type of motif is particularly useful for the generation of new analogs suitable for medicinal chemistry goals. In this article, we analyzed the oxidation pattern of ibogaine and voacangine using dioxygen, peroxo compounds, and iodine as oxidizing agents. Special focus was placed on the study of the regio- and stereochemistry of the oxidation processes according to the oxidative agent and starting material. We found that the C16-carboxymethyl ester present in voacangine stabilizes the whole molecule toward oxidation in comparison to ibogaine, especially in the indole ring, where 7-hydroxy- or 7-peroxy-indolenines can be obtained as oxidation products. Nevertheless, the ester moiety enhances the reactivity of the isoquinuclidinic nitrogen to afford C3-oxidized products through a regioselective iminium formation. This differential reactivity between ibogaine and voacangine was rationalized using computational DFT calculations. In addition, using qualitative and quantitative NMR experiments combined with theoretical calculations, the absolute stereochemistry at C7 in the 7-hydroxyindolenine of voacangine was revised to be S, which corrects previous reports proposing an R configuration.


Assuntos
Ibogaína , Tabernaemontana , Ibogaína/farmacologia , Ibogaína/química , Tabernaemontana/química , Oxirredução , Esqueleto
7.
J Nat Prod ; 86(5): 1202-1210, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37155823

RESUMO

The molecular network-guided exploration of the alkaloid extract of Callichilia inaequalis stems revealed a cluster attributed tentatively to dimeric monoterpene indole alkaloids of the rare criophylline subtype, initiating the dual study reported herein. A patrimonial-themed portion of this work was aimed at performing a spectroscopic reassessment of criophylline (1), a monoterpene bisindole alkaloid for which the nature of the inter-monomeric connectivity and configurational assignments have remained dubious. A targeted isolation of the entity annotated as criophylline (1) was undertaken to strengthen the available analytical evidence. An extensive set of spectroscopic data was acquired from the authentic sample of criophylline (1a) isolated earlier by Cavé and Bruneton. These spectroscopic studies proved the samples to be identical, and the complete structure of criophylline could be assigned, half a century after it was first isolated. The absolute configuration of andrangine (2) was also ascertained based on a TDDFT-ECD approach from the authentic sample. The forward-looking aspect of this investigation resulted in the characterization of two new criophylline derivatives from C. inaequalis stems, namely, 14'-hydroxycriophylline (3) and 14'-O-sulfocriophylline (4). Their structures, including absolute configurations, were elucidated by analysis of NMR and MS spectroscopic data and by ECD analysis. Notably, 14'-O-sulfocriophylline (4) is the first sulfated monoterpene indole alkaloid to have been reported. The antiplasmodial activity against the chloroquine-resistant strain of Plasmodium falciparum FcB1 was determined for criophylline and its two new analogues.


Assuntos
Alcaloides , Antineoplásicos , Tabernaemontana , Alcaloides/química , Cloroquina , Alcaloides Indólicos/química , Monoterpenos , Estrutura Molecular
8.
Fitoterapia ; 167: 105506, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37068714

RESUMO

The structures of the recently published monoterpene indole alkaloids penduflorines A and B (1a and 1b), isolated from Tabernaemontana penduliflora (Apocynaceae), have been revised. Rather than an inseparable mixture of two compounds, they appear to be the known alkaloid vobasine (2). Although we could not comprehensively revise the structures of penduflorines C-E due to lacking spectral data, since their structural elucidations were based on that of 1a and 1b, their structures should also be treated with caution.


Assuntos
Alcaloides , Antineoplásicos Fitogênicos , Apocynaceae , Tabernaemontana , Tabernaemontana/química , Estrutura Molecular , Alcaloides Indólicos/química , Antineoplásicos Fitogênicos/química
9.
Chin J Nat Med ; 21(2): 146-153, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36871982

RESUMO

Four unreported monoterpene indole alkaloids, tabernaecorymines B-E (1-4), together with twenty-one known indole alkaloids (5-25) were obtained from the stem bark of Tabernaemontana corymbosa. Their structures and absolute configurations were elucidated by extensive spectroscopy, quantum chemical calculations, DP4+ probability analyses and Mo2(OAc)4-induced electronic circular dichroism experiment. The antibacterial and antifungal activities of these compounds were evaluated and some of them showed significant activity against Staphylococcus aureus,Bacillus subtilis, Streptococcus dysgalactiae and Candida albicans.


Assuntos
Anti-Infecciosos , Tabernaemontana , Antifúngicos , Antibacterianos , Alcaloides Indólicos
10.
Phytochemistry ; 208: 113587, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36646163

RESUMO

Eight undescribed iboga alkaloids, polyneurines A-H, were isolated from the bark of Tabernaemontana polyneura. The structures of these alkaloids were established by interpretation of the MS and NMR data, while the configurations were determined using GIAO NMR calculations and DP4+ probability analysis, TDDFT-ECD method, or X-ray diffraction analysis. Polyneurine A possesses a γ-lactone unit embedded within the iboga skeleton, while polyneurines D and E incorporate a formylmethyl moiety at C-3 of the iboga skeleton. Biosynthetic pathways towards the formation of polyneurines A, C, D, and E were proposed.


Assuntos
Alcaloides , Tabernaemontana , Tabernaemontana/química , Alcaloides Indólicos/química , Alcaloides/química , Cristalografia por Raios X , Estrutura Molecular
11.
Int J Mol Sci ; 24(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36675001

RESUMO

Eleven monoterpenoid indole alkaloids, including three new ones, tabercrassines A-C (1-3), were isolated from the seeds of Tabernaemontana crassa. Tabercrassine A (1) is an ibogan-ibogan-type bisindole alkaloid which is formed by the polymerization of two classic ibogan-type monomers through a C3 unit aliphatic chain. Their structures were established by extensive analysis of HRESIMS, NMR, and ECD spectra. Cellular assays showed that alkaloids 1-3 all reduce Aß42 production and inhibit phospho-tau (Thr217), a new biomarker of Alzheimer's disease [AD] associated with BACE1-, NCSTN-, GSK3ß-, and CDK5-mediated pathways, suggesting these alkaloids' potential against AD.


Assuntos
Antineoplásicos Fitogênicos , Alcaloides de Triptamina e Secologanina , Tabernaemontana , Alcaloides de Triptamina e Secologanina/farmacologia , Alcaloides de Triptamina e Secologanina/química , Alcaloides Indólicos/farmacologia , Tabernaemontana/química , Secretases da Proteína Precursora do Amiloide , Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Ácido Aspártico Endopeptidases , Estrutura Molecular
12.
Environ Sci Pollut Res Int ; 30(10): 24856-24875, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35013966

RESUMO

Silver nanoparticles (Ag NPs) were synthesised by the reduction of Ag+ to Ag0 in the presence of enol form of flavonoids present in plant extract of Tabernaemontana divaricate (T. divaricate). Prepared Ag NPs were characterised using UV-Vis, XRD, HR-TEM with EDX and XPS techniques. XPS spectra exhibited peaks at 366 eV and 373 eV, which specified spin orbits for Ag 3d3/2, and Ag 3d5/2 that confirmed the formation of Ag NPs. Ag NPs were spherical in shape with an average size of 30 nm as revealed by HR-TEM and FE-SEM techniques. EDX studies verified the high purity of Ag NPs with silver 46.96%, carbon 16.35%, oxygen 16.22%, nitrogen 20.25% and sulphur 0.21%. LC-MS analysis of plant extract confirmed the qualitative presence of alkaloids, tannins, flavonoids, phenols, and carbohydrates. Prepared Ag NPs showed good photocatalytic activity towards degradation of 4-Amniopyridine with 61% degradation efficiency at optimum conditions in 2 h of reaction time under visible light. The ten intermediates were found within the mass number of 0-450. Ag NPs synthesised using bio-extract have also shown good inactivation against Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis) bacteria due to the availability of free radicals.


Assuntos
Nanopartículas Metálicas , Tabernaemontana , Prata/farmacologia , Tabernaemontana/metabolismo , Escherichia coli/metabolismo , 4-Aminopiridina , Espectroscopia de Infravermelho com Transformada de Fourier , Extratos Vegetais/farmacologia , Flavonoides , Antibacterianos/farmacologia
13.
Planta Med ; 89(2): 148-157, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35338475

RESUMO

Plants of Tabernaemontana species have several pharmacological activities including antimicrobial effects. Amoebiasis continues to be a public health problem, with increasing evidence of resistance to metronidazole. In this study, we assessed the effect of the alkaloid fraction of T. arborea root bark and the alkaloids ibogaine and voacangine on the viability and infectivity of Entamoeba histolytica trophozoites. Cultures were exposed to 0.1 - 10 µg/mL for 24, 48 and 72 h, and viability was then determined using a tetrazolium dye reduction assay and type of cellular death analyzed by flow cytometry. Results showed that the alkaloid fraction, but mainly ibogaine and voacangine alkaloids, exhibited potent dose-dependent anti-amoebic activity at 24 h post-exposure (IC50 4.5 and 8.1 µM, respectively), comparable to metronidazole (IC50 6.8 µM). However, the effect decreased after 48 and 72 h of exposure to concentrations below 10 µg/mL, suggesting that the alkaloids probably were catabolized to less active derivatives by the trophozoites. The treatment of trophozoites with the IC50 s for 24 h induced significant morphological changes in the trophozoites, slight increase in granularity, and death by apoptonecrosis. The capacity of T. arborea alkaloids to inhibit the development of amoebic liver abscesses in hamsters was evaluated. Results showed that even when the treatments reduced the number of amoebic trophozoites in tissue sections of livers, they were unable to limit the formation of abscesses, suggesting their rapid processing to inactive metabolites. This work leaves open the possibility of using Tabernaemontana alkaloids as a new alternative for amoebiasis control.


Assuntos
Alcaloides , Amebíase , Ibogaína , Tabernaemontana , Ibogaína/metabolismo , Ibogaína/farmacologia , Metronidazol/farmacologia , Metronidazol/metabolismo , Casca de Planta , Alcaloides/farmacologia , Alcaloides/metabolismo
14.
Nat Prod Res ; 37(2): 322-327, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34319175

RESUMO

Extraction methods like maceration, ultrasonication, vortex mixer, soxhlet extraction and microwave assisted extraction (MAE), were evaluated for the extraction of Camptothecin (CPT) from the leaves and stem of Tabernaemontana alternifolia, Tabernaemontana divaricata and Tabernaemontana citrifolia. The extracts were analyzed by high performance thin layer chromatography (HPTLC). The results show that the leaves of Tabernaemontana alternifolia exhibited highest yield of CPT as compared to the other species. MAE was the most efficient extraction method with CPT extraction yield of 0.154 ± 0.004% w/w from Tabernaemontana alternifolia leaves followed by Soxhlet extraction, sonication, maceration, and vortex extraction methods.


Assuntos
Tabernaemontana , Tabernaemontana/química , Folhas de Planta/química , Camptotecina , Extratos Vegetais/química
15.
Drug Alcohol Rev ; 42(2): 401-414, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36456173

RESUMO

INTRODUCTION: Ibogaine is one of the alkaloids naturally found in plants such as Tabernanthe iboga, which has been traditionally used by members of the Bwiti culture. Since the discovery of its anti-addictive properties by Howard S. Lotsof in 1962, ibogaine has been used experimentally to treat substance use disorders (SUD), especially those involving opioids. We aim to provide a detailed understanding of the underlying psychological aspects of underground ibogaine use for the treatment of SUD. METHODS: Semi-structured interviews were carried out with 13 participants with SUD, which motivated their self-treatment with ibogaine. The data were analysed using the grounded theory approach and considered the context of the treatment, and the nature of the occurring hallucinogenic and cognitive phenomena during the treatment experience. RESULTS: We identified several psychological effects that the study respondents experienced, which seem to play a substantial role in the therapeutic process concerning SUD. The evoking of interpersonal and transpersonal experiences, autobiographical memories, and preparation, integration and motivation for a lifestyle change are important components that participants reported during and after ibogaine intake. DISCUSSION AND CONCLUSION: Ibogaine is increasingly being used for the treatment of SUD, due in part to the limited treatment options currently available. Its beneficial effects seem to be related not only to its complex pharmacology but also to the subjective experience that ibogaine induces. The main aspects of this experience are related to autobiographical memories and valuable personal insights, which together appear to help individuals cope with their SUD.


Assuntos
Alcaloides , Ibogaína , Transtornos Relacionados ao Uso de Substâncias , Tabernaemontana , Humanos , Ibogaína/uso terapêutico , Ibogaína/farmacologia , Alcaloides/uso terapêutico , Transtornos Relacionados ao Uso de Substâncias/tratamento farmacológico
16.
Biochimie ; 206: 105-115, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36273763

RESUMO

Snake envenomation is an ongoing global health problem and tropical neglected disease that afflicts millions of people each year. The only specific treatment, antivenom, has several limitations that affects its proper distribution to the victims and its efficacy against local effects, such as myonecrosis. The main responsible for this consequence are the phospholipases A2 (PLA2) and PLA2-like proteins, such as BthTX-I from Bothrops jararacussu. Folk medicine resorts to plants such as Tabernaemontana catharinensis to palliate these and other snakebite effects. Here, we evaluated the effect of its root bark extract and one of its isolated compounds, 12-methoxy-4-methyl-voachalotine (MMV), against the in vitro paralysis and muscle damage induced by BthTX-I. Secondary and quaternary structures of BthTX-I were not modified by the interaction with MMV. Instead, this compound interacted in an unprecedented way with the region inside the toxin hydrophobic channel and promoted a structural change in Val31, loop 58-71 and Membrane Disruption Site. Thus, we hypothesize that MMV inhibits PLA2-like proteins by preventing entrance of fatty acid into the hydrophobic channel. These data may explain the traditional use of T. catharinensis extract and confirm MMV as a promising candidate to complement antivenom or a structural guide to develop more effective inhibitors.


Assuntos
Bothrops , Venenos de Crotalídeos , Tabernaemontana , Animais , Antivenenos/farmacologia , Antivenenos/química , Tabernaemontana/metabolismo , Fosfolipases A2/química , Venenos de Serpentes , Venenos de Crotalídeos/química , Bothrops/metabolismo
17.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-971669

RESUMO

Four unreported monoterpene indole alkaloids, tabernaecorymines B-E (1-4), together with twenty-one known indole alkaloids (5-25) were obtained from the stem bark of Tabernaemontana corymbosa. Their structures and absolute configurations were elucidated by extensive spectroscopy, quantum chemical calculations, DP4+ probability analyses and Mo2(OAc)4-induced electronic circular dichroism experiment. The antibacterial and antifungal activities of these compounds were evaluated and some of them showed significant activity against Staphylococcus aureus,Bacillus subtilis, Streptococcus dysgalactiae and Candida albicans.


Assuntos
Tabernaemontana , Anti-Infecciosos , Antifúngicos , Antibacterianos , Alcaloides Indólicos
18.
Indian J Dent Res ; 34(3): 242-246, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38197339

RESUMO

Context: Many parts of Tabernaemontana divaricata (T. divaricata) including its leaf is used for the analgesic and antibacterial purpose by Adivasis of Kerala. Aims: To evaluate the antibacterial potential of T. divaricata against common caries pathogens like S. mutans and L. acidophilus. Settings and Design: Research is done in Biogenix Research Lab, Thiruvananthapuram. Methods and Material: Ethyl alcoholic extract of T. divaricata leaves is tested for its antibacterial action against common caries pathogens at various levels. It includes assessing the leaves' antibacterial activity, acid production of bacteria in the presence of the study sample, Minimum inhibitory concentration (MIC), minimum bacterial concentration (MBC) and colony forming units (CFU) levels in the presence of the leaf extract. Statistical Analysis Used: In descriptive statistics, mean and standard deviation is used. Mann-Whitney U test, Independent Students T-test, Student Paired T-test, and One-way ANOVA followed by Turkeys Post hoc analysis are the tests used in inferential statistics. Results: It is found that T. divaricata has substantial antibacterial action against S. mutans and L. acidophilus. Conclusions: Our indigenous plants have a lot of medicinal properties. T. divaricata is no exception to this, though it is commonly considered as a garden plant. In the current study, it has been proven that its leaves have antibacterial action against oral pathogens. So, the research has to be taken to a further level for its medicinal application.


Assuntos
Cárie Dentária , Tabernaemontana , Análise de Variância , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
19.
Phytochemistry ; 203: 113384, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36007666

RESUMO

Thirteen indole alkaloids comprising six vobasine/sarpagine, one vincamine, two voaphylline, two tacaman, one iboga, and one corynantheine alkaloid, were isolated from the leaf extract of Tabernaemontana corymbosa (sample from Taiping, Perak, Malaysia). The structures of these alkaloids were determined based on analysis of the spectroscopic data (NMR and MS), and in the case of vincarudine, the absolute configuration was established by ECD and X-ray diffraction analysis. Vobasidine E represents the first vobasine-type alkaloid characterized by a contracted ring C and loss of the ethylidene/ethyl side chain. A possible biogenetic pathway from a perivine precursor, which was also present in the leaf extract, is presented. Differences in the new alkaloid content between the present and previous sample of the same plant (occurring in a different location) are discussed.


Assuntos
Alcaloides , Antineoplásicos Fitogênicos , Tabernaemontana , Vincamina , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Alcaloides Indólicos/química , Estrutura Molecular , Extratos Vegetais , Tabernaemontana/química
20.
Sci Rep ; 12(1): 11030, 2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35773400

RESUMO

Reichardia Roth is a small Mediterranean genus comprising ten homogeneous species with basic chromosome numbers of 7, 8, and 9. To assess the plastid genome evolution and differentiation of Reichardia species, we assembled the complete plastome sequences of seven Reichardia and two Launaea species and conducted various phylogenomic analyses comparatively with nuclear ribosomal DNA ITS sequences. Reichardia and Launaea plastomes were highly conserved in gene content and order, containing 130 genes. Plastid phylogenomic reconstruction strongly suggested that Reichardia was a sister to Launaea, and its common ancestor initially diverged into two major lineages: the first containing species with n = 8 chromosomes exclusively, and the other with n = 9, 8, and 7 chromosomes. Although the ancestral Reichardia karyotype was suggested to most likely be n = 9 from ancestral chromosome number reconstruction, the pattern of descending dysploidy indicated by the phylogenetic trees based on nuclear ribosomal DNA ITS was less evident in the trees based on the plastome. Possible reasons for these findings are discussed.


Assuntos
Asteraceae , Genomas de Plastídeos , Tabernaemontana , Asteraceae/genética , DNA Ribossômico/genética , Evolução Molecular , Filogenia
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