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1.
Planta ; 257(3): 51, 2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36757512

RESUMO

MAIN CONCLUSION: The polyploidization of Hippeastrum papilio influences its primary and secondary metabolism including the biosynthesis of bioactive alkaloids. Hippeastrum papilio is an ornamental plant that has advantages in comparison to the currently used plants for the extraction of galanthamine, a natural compound used for the cognitive treatment of Alzheimer's disease. In the present study, an autotetraploid line of H. papilio was induced for the first time, after treatment with 0.05% colchicine for 48 h. The chromosome number in diploids was found to be 2n = 2x = 22 and for autotetraploids 2n = 4x = 44. The flow cytometric analyses detected a DNA C-value of 14.88 ± 0.03 pg (1C) in diploids and 26.57 ± 0.12 pg in autotetraploids. The morphological, cytological, and phytochemical studies showed significant differences between diploids and autotetraploids. The length and width of stomata in autotetraploids were 22.47% and 17.94%, respectively, larger than those observed in the diploid leaves. The biomass of one-year-old autotetraploid H. papilio plants was reduced by 53.99% for plants' fresh weight, 56.53% for leaves' fresh weight, and 21.70% for bulb diameter. The GC-MS analysis of methanol extracts from one-year-old diploid and autotetraploid H. papilio plants revealed over 60 primary and secondary metabolites including alkaloids, phenolic acids, sterols, saccharides, and alcohols, among others. Principal component analysis of the metabolite profiles indicates a divergence of the metabolism between diploid and autotetraploid plants. The content of galanthamine and haemanthamine was found to be 49.73% and 80.10%, respectively, higher in the leaves of autotetraploids, compared to the diploid ones. The biosynthesis of the saccharides shows a tendency to be upregulated in tetraploid plants, while that of phenolic acids was downregulated. Polyploidization of H. papilio creates possibilities for further crop improvement aimed at high-galanthamine-producing genotypes.


Assuntos
Alcaloides , Diploide , Galantamina , Plantas , Tetraploidia , Compostos Fitoquímicos
2.
Rapid Commun Mass Spectrom ; 37(12): e9506, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-36942466

RESUMO

RATIONALE: Gas chromatography-mass spectrometry (GC-MS) is the most frequently applied technique for analyzing Amaryllidaceae alkaloids in plant extracts. Having these compounds, known for their potent bioactivities, is a distinctive chemotaxonomic feature of the Amaryllidoideae subfamily (Amaryllidaceae). The Amaryllidaceae alkaloids of homolycorine type with a C3-C4 double bond generally show molecular and diagnostic ions at the high-mass region with low intensity in the EIMS mode, leading to problematic identification in complex plant extracts. METHODS: Eleven standard homolycorine-type alkaloids (isolated and identified by 1D and 2D nuclear magnetic resonance) were subjected to separation with GC and studied with electron impact mass spectrometry (EIMS) including single quadrupole (GC-EIMS), tandem (GC-EIMS/MS), and high-resolution (GC-HR-EIMS) detectors, as well as with chemical ionization mass spectrometry (GC-CIMS). Alkaloid fractions from two Hippeastrum species and Clivia miniata were subjected to GC-EIMS and GC-CIMS for alkaloid identification. RESULTS: GC-EIMS in combination with GC-CIMS provided significant structural information of homolycorine-type alkaloids with C3-C4 double bond, facilitating their unambiguous identification. Based on the obtained typical fragmentation, other 11 homolycorine-type compounds were identified in extracts from two Hippeastrum species by parallel GC-EIMS, GC-CIMS, and liquid chromatography-electrospray ionization time-of-flight mass spectrometry and in extracts from C. miniata by GC-EIMS. CONCLUSIONS: GC-MS can be successfully applied for the identification of new and known homolycorine-type alkaloids, among others within the Amaryllidoideae subfamily, as well as for chemotaxonomical and chemoecological studies.


Assuntos
Alcaloides , Alcaloides de Amaryllidaceae , Amaryllidaceae , Alcaloides de Amaryllidaceae/química , Cromatografia Gasosa-Espectrometria de Massas , Alcaloides/química , Extratos Vegetais/química
3.
Molecules ; 28(14)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37513280

RESUMO

The genus Clinanthus Herb. is found in the Andes Region (South America), mainly in Peru, Ecuador, and Bolivia. These plants belong to the Amaryllidaceae family, specifically the Amaryllidoideae subfamily, which presents an exclusive group of alkaloids known as Amaryllidaceae alkaloids that show important structural diversity and pharmacological properties. It is possible to find some publications in the literature regarding the botanical aspects of Clinanthus species, although there is little information available about their chemical and biological activities. The aim of this work was to obtain the alkaloid profile and the anti-cholinesterase activity of four different samples of Clinanthus collected in South America: Clinanthus sp., Clinanthus incarnatus, and Clinanthus variegatus. The alkaloid extract of each sample was analyzed by gas chromatography coupled with mass spectrometry (GC-MS), and their potential against the enzymes acetyl- and butyrylcholinesterase were evaluated. Thirteen alkaloids have been identified among these species, while six unidentified structures have also been detected in these plants. The alkaloid extract of the C. variegatus samples showed the highest structural diversity as well as the best activity against AChE, which was likely due to the presence of the alkaloid sanguinine. The results suggest this genus as a possible interesting new source of Amaryllidaceae alkaloids, which could contribute to the development of new medicines.


Assuntos
Alcaloides , Alcaloides de Amaryllidaceae , Amaryllidaceae , Alcaloides de Amaryllidaceae/farmacologia , Butirilcolinesterase/química , Amaryllidaceae/química , Alcaloides/química , Inibidores da Colinesterase/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , América do Sul
4.
Molecules ; 28(3)2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36770905

RESUMO

Amaryllidaceae alkaloids are secondary metabolites with interesting medicinal properties. Almost every Narcissus species can synthesize them and constitute an excellent source for their isolation and study. Several Amaryllidaceae alkaloids have shown acetylcholinesterase inhibitory activities and are a promising tool for treating cholinergic disorders such as Alzheimer's disease (AD). Indeed, three of the four palliative treatments approved for AD are acetylcholinesterase (AChE) inhibitors and one of them, galanthamine, is an Amaryllidaceae alkaloid itself. This molecule is currently isolated from natural sources. However, its production is insufficient to supply the increasing demand for the active principle. Our main aim is to discover tools to improve galanthamine production and to prospect for potential new and more efficient drugs for AD treatment. Furthermore, we seek to broaden the knowledge of plants of the genus Narcissus from a chemotaxonomic perspective. Hence, in this study, we evaluate the alkaloid content through GC-MS and the AChE inhibitory activity of ten autumn-flowering Narcissus, which have been less studied than their spring-flowering counterparts. A total of thirty Amaryllidaceae alkaloids have been found, twenty-eight properly identified. Two Narcissus contained galanthamine, and seven were able to inhibit AChE.


Assuntos
Alcaloides de Amaryllidaceae , Amaryllidaceae , Narcissus , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Amaryllidaceae/química , Alcaloides de Amaryllidaceae/farmacologia , Inibidores da Colinesterase , Galantamina/farmacologia , Narcissus/química
5.
J Appl Biomed ; 21(1): 36-47, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37016777

RESUMO

Skin cancer has high rates of mortality and therapeutic failure. In this study, to develop a multi-agent strategy for skin cancer management, the selective cytotoxicity of several alkaloid fractions and pure alkaloids isolated from Amaryllidaceae species was evaluated in melanoma cells. In addition, UVB-stimulated keratinocytes (HaCaT) were exposed to seven alkaloid fractions characterized by GC-MS, and the production of intracellular reactive oxygen species (ROS) and IL-6, were measured to evaluate their photoprotection effects. The Eucharis caucana (bulb) alkaloid fraction (20 µg/ml) had a clear effect on the viability of melanoma cells, reducing it by 45.7% without affecting healthy keratinocytes. This alkaloid fraction and tazettine (both at 2.5 µg/ml) suppressed UVB-induced ROS production by 31.6% and 29.4%, respectively. The highest anti-inflammatory potential was shown by the Zephyranthes carinata (bulb) alkaloid fraction (10 µg/ml), which reduced IL-6 production by 90.8%. According to the chemometric analysis, lycoramine and tazettine had a photoprotective effect on the UVB-exposed HaCaT cells, attenuating the production of ROS and IL-6. These results suggest that Amaryllidaceae alkaloids have photoprotective and therapeutic potential in skin cancer management, especially at low concentrations.


Assuntos
Alcaloides , Alcaloides de Amaryllidaceae , Melanoma , Neoplasias Cutâneas , Humanos , Alcaloides de Amaryllidaceae/farmacologia , Espécies Reativas de Oxigênio/farmacologia , Interleucina-6 , Alcaloides/farmacologia , Queratinócitos , Neoplasias Cutâneas/tratamento farmacológico , Melanoma/tratamento farmacológico
6.
Rapid Commun Mass Spectrom ; 35(14): e9116, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33928691

RESUMO

RATIONALE: Narcissus cv. Hawera has been found to biosynthesize some Sceletium-type alkaloids with antidepressant and anxiolytic activities. This ornamental plant has been poorly studied as a source of bioactive alkaloids including some contraversive reports on in vitro and intact plants. In this study, a detailed GC-MS characterization of its alkaloid fractions is presented. METHODS: GC-MS was used for the identification of compounds in the alkaloid fractions. Both underivatized and silylated samples were analyzed simultaneously. Elevated plus maze and tail suspension tests were used to assay the anxiolytic and antidepressant activities. Ellman's and MTT-dye reduction assays were used to evaluate the acetylcholinesterase (AChE) inhibitory and cytotoxicity activities, respectively. RESULTS: Of the 29 alkaloids, 13 of Sceletium-type were detected. Two new alkaloids were identified as 2-oxo-mesembrine and 2-oxo-epi-mesembrenol. Lycorine was found as a major compound (43.5%) in the crude silylated methanol extract. After the elimination of lycorine by pre-crystallization, the major alkaloids were 40.8% 6-epi-mesembranol, 16.2% 6-epi-mesembrenol, and 13.8% sanguinine. This fraction showed anxiolytic and antidepressant-like activities as well as potent AChE inhibitory and antineoplastic activities. CONCLUSIONS: Silylation of the alkaloid fractions from Narcissus cv. Hawera provides better separation, structural information, and improved sensitivity for compounds with two and more hydroxyl groups. The lycorine-free alkaloid fraction shows a great potential for further pharmacological studies.


Assuntos
Alcaloides , Cromatografia Gasosa-Espectrometria de Massas/métodos , Narcissus/química , Extratos Vegetais/química , Aizoaceae , Alcaloides/análise , Alcaloides/farmacologia , Alcaloides/toxicidade , Amaryllidaceae , Animais , Ansiolíticos/análise , Ansiolíticos/farmacologia , Ansiolíticos/toxicidade , Comportamento Animal/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos ICR
7.
Chem Biodivers ; 18(3): e2000834, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33594810

RESUMO

The Libellus de Medicinalibus Indorum Herbis (Booklet of Indian Medicinal Plants) is the first book of medicinal plants written in the American continent. It was first published in 1939 as 'An Aztec Herbal'. One of the depicted plants is Huetzcanixochitl (laughing flower) interpreted as Zephyranthes fosteri (Amaryllidaceae). No chemical or pharmacological studies are reported for this species; so, we decide to investigate it. The GC/MS of the bulbs and aerial parts extracts indicated that they contain Amaryllidaceae alkaloids, among them: lycorine, 3-O-acetylpowelline, and norlycoramine. An unknown major alkaloid was isolated and identified by 1 H, 13 C-NMR and MS, as 3'-demethoxy-6-epimesembranol (1). The methanolic extract, the alkaloid fraction, and compound 1 inhibited acetylcholinesterase in vitro. Mesembrine alkaloids are found in Sceletium species (Aizoaceae). Several are known as serotonin recapture inhibitors and have been proposed as potential antidepressant drugs. The presence of 1 suggests that Z. fosteri was probably used in pre-Columbian times in Mexico as a 'stimulant and euphoriant', alike Sceletium tortuosum by several ethnic groups in South Africa.


Assuntos
Alcaloides/farmacologia , Amaryllidaceae/química , Inibidores da Colinesterase/farmacologia , Compostos Fitoquímicos/farmacologia , Plantas Medicinais/química , Acetilcolinesterase/metabolismo , Alcaloides/química , Alcaloides/isolamento & purificação , Animais , Inibidores da Colinesterase/química , Inibidores da Colinesterase/isolamento & purificação , Relação Dose-Resposta a Droga , Electrophorus , México , Estrutura Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Estereoisomerismo , Relação Estrutura-Atividade
8.
Molecules ; 26(1)2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33401696

RESUMO

Plants in the Amaryllidaceae family synthesize a diversity of bioactive alkaloids. Some of these plant species are not abundant and have a low natural multiplication rate. The aims of this work were the alkaloids analysis of a Habranthus cardenasianus bulbs extract, the evaluation of its inhibitory activity against cholinesterases, and to test several propagation strategies for biomass production. Eleven compounds were characterized by GC-MS in the alkaloid extract, which showed a relatively high proportion of tazettine. The known alkaloids tazettine, haemanthamine, and the epimer mixture haemanthidine/6-epi-haemanthidine were isolated and identified by spectroscopic methods. Inhibitory cholinesterases activity was not detected. Three forms of propagation were performed: bulb propagation from seed, cut-induced bulb division, and micropropagated bulbs. Finally, different imbibition and post-collection times were evaluated in seed germination assays. The best propagation method was cut-induced bulb division with longitudinal cuts into quarters (T1) while the best conditions for seed germination were 0-day of post-collection and two days of imbibition. The alkaloids analyses of the H. cardenasianus bulbs showed that they are a source of anti-tumoral alkaloids, especially pretazettine (tazettine) and T1 is a sustainable strategy for its propagation and domestication to produce bioactive alkaloids.


Assuntos
Alcaloides/análise , Alcaloides/farmacologia , Amaryllidaceae/química , Amaryllidaceae/crescimento & desenvolvimento , Inibidores da Colinesterase/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides de Amaryllidaceae/análise , Biomassa , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Cromatografia Gasosa-Espectrometria de Massas , Germinação , Estrutura Molecular , Fenantridinas/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Raízes de Plantas/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Fatores de Tempo
9.
S Afr J Bot ; 136: 91-99, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32982003

RESUMO

Alzheimer's disease is considered the most common cause of dementia and, in an increasingly aging population worldwide, the quest for treatment is a priority. Amaryllidaceae alkaloids are of main interest because of their cholinesterase inhibition potential, which is the main palliative treatment available for this disease. We evaluated the alkaloidal profile and the in vitro inhibitory activity on acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) of bulb alkaloid extract of Phaedranassa dubia and Phaedranassa brevifolia collected in Ecuador. Using gas chromatography coupled to mass spectrometry (GC-MS), we identified typical Amaryllidaceae alkaloids in these species, highlighting the presence of lycorine-type alkaloids in P. dubia and haemanthamine/crinine-type in P. brevifolia. The species P. dubia and P. brevifolia showed inhibitory activities against AChE (IC50 values of 25.48 ± 0.39 and 3.45 ± 0.29 µg.mL-1, respectively) and BuChE (IC50 values of 114.96 ± 4.94 and 58.89 ± 0.55 µg.mL-1, respectively). Computational experiments allowed us to understand the interactions of the alkaloids identified in these samples toward the active sites of AChE and BuChE. In silico, some alkaloids detected in these Amaryllidaceae species presented higher estimated binding free energy toward BuChE than galanthamine. This is the first study about the alkaloid profile and biological potential of P. brevifolia species.

10.
Molecules ; 25(9)2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32365796

RESUMO

It is estimated that 50 million people in the world live with dementia, 60-70% of whom suffer from Alzheimer's disease (AD). Different factors are involved in the development of AD, including a reduction in the cholinergic neurotransmission level. The Amaryllidaceae plant family contains an exclusive, large, and still understudied alkaloid group characterized by a singular skeleton arrangement and a broad spectrum of biological activities. The chemistry and biodiversity of Ecuadorian representatives of the Phaedranassa genus (Amaryllidaceae) have not been widely studied. In this work, five Ecuadorian Phaedranassa species were examined in vitro for their activity towards the enzymes acetyl- (AChE) and butyrylcholinesterase (BuChE), and the alkaloid profile of bulb extracts was analyzed by GC-MS. The species Phaedranassa cuencana and Phaedranassa dubia showed the most AChE and BuChE inhibitory activity, respectively. To obtain insight into the potential role of the identified alkaloids in these inhibitory effects, docking experiments were carried out, and cantabricine showed in silico inhibitory activity against both cholinesterase structures. Our results show that Amaryllidaceae species from Ecuador are a potential source of new drugs for the palliative treatment of AD.


Assuntos
Amaryllidaceae/química , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Acetilcolinesterase/química , Alcaloides/química , Alcaloides/farmacologia , Sítios de Ligação , Descoberta de Drogas , Equador , Cromatografia Gasosa-Espectrometria de Massas , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Ligação Proteica , Relação Estrutura-Atividade
11.
Chem Biodivers ; 16(5): e1800662, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30801949

RESUMO

Plants of the Amaryllidaceae family are well-known (not only) for their ornamental value but also for the alkaloids that they produce. In this report, the first phytochemical study of Clinanthus genus was carried out. The chemical composition of alkaloid fractions from Clinanthus microstephium was analyzed by GC/MS and NMR. Seven known compounds belonging to three structural types of Amaryllidaceae alkaloids were identified. An epimeric mixture of a haemanthamine-type compound (6-hydroxymaritidine) was tested as an inhibitor against acetyl- and butyrylcholinesterase enzymes (AChE and BChE, respectively), two enzymes relevant in the treatment of Alzheimer's disease, with good results. Structure-activity relationships through molecular docking studies with this alkaloid and other structurally related compounds were discussed.


Assuntos
Alcaloides/química , Alcaloides de Amaryllidaceae/química , Amaryllidaceae/química , Inibidores da Colinesterase/química , Fenantridinas/química , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Alcaloides/metabolismo , Alcaloides/farmacologia , Amaryllidaceae/metabolismo , Sítios de Ligação , Butirilcolinesterase/química , Butirilcolinesterase/metabolismo , Domínio Catalítico , Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Extratos Vegetais/química , Relação Estrutura-Atividade
12.
Molecules ; 23(7)2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29949847

RESUMO

Amaryllidaceae plants are the commercial source of galanthamine, an alkaloid approved for the clinical treatment of Alzheimer's disease. The chemistry and bioactivity of Chilean representatives of Rhodophiala genus from the family of Amaryllidaceae have not been widely studied so far. Ten collections of five different Chilean Rhodophiala were analyzed in vitro for activity against enzymes such as acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) as well as for their alkaloid composition by GC-MS. To obtain an insight into the potential AChE and BuChE inhibitory activity of the alkaloids identified in the most active samples, docking experiments were carried out. Although galanthamine was found neither in aerial parts nor in bulbs of R. splendens, these plant materials were the most active inhibitors of AChE (IC50: 5.78 and 3.62 µg/mL, respectively) and BuChE (IC50: 16.26 and 14.37 µg/mL, respectively). Some 37 known alkaloids and 40 still unidentified compounds were detected in the samples, suggesting high potential in the Chilean Amaryllidaceae plants as sources of both novel bioactive agents and new alkaloids.


Assuntos
Alcaloides/farmacologia , Amaryllidaceae/química , Inibidores da Colinesterase/farmacologia , Simulação de Acoplamento Molecular , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Alcaloides/química , Biomassa , Butirilcolinesterase/química , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Termodinâmica
13.
Molecules ; 23(6)2018 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-29861456

RESUMO

Natural products play an important role in the development of new drugs. In this context, the Amaryllidaceae alkaloids have attracted considerable attention in view of their unique structural features and various biological activities. In this study, twenty-three alkaloids were identified from Crinum amabile by GC-MS and two new structures (augustine N-oxide and buphanisine N-oxide) were structurally elucidated by NMR. Anti-parasitic and cholinesterase (AChE and BuChE) inhibitory activities of six alkaloids isolated from this species, including the two new compounds, are described herein. None of the alkaloids isolated from C. amabile gave better results than the reference drugs, so it was possible to conclude that the N-oxide group does not increase their therapeutic potential.


Assuntos
Alcaloides/química , Crinum/química , Óxidos/química , Alcaloides/farmacologia , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/farmacologia , Antiprotozoários/química , Antiprotozoários/farmacologia , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Compostos Fitoquímicos , Extratos Vegetais/química
14.
Exp Parasitol ; 173: 18-28, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27956086

RESUMO

Tritrichomonas foetus infects the bovine urogenital tract, causing bovine trichomoniasis. Significant economic losses may occur due to infertility and abortion among cattle. Trichomonas vaginalis is the causative agent of trichomoniasis; the most common but overlooked non-viral sexually transmitted disease worldwide. Human and bovine trichomoniasis present treatment restrictions and efforts to identify new alternatives are essential. The present study evaluated the anti-trichomonads activities of seven fractions from northwest endemic plant Manilkara rufula. Flavonoids and condensed tannins were identified from these fractions by LC-DAD-MS/MS and MALDI-MS/MS. Altogether, the results demonstrated for the first time the structural description of tannins from leaves of M. rufula and the relation of these compounds with anti-T. vaginalis and anti-T. foetus activities. Overall, this report reveals the potential of M. rufula fractions against both parasites and shows new alternatives to treat the infection caused by trichomonads.


Assuntos
Antitricômonas/farmacologia , Flavonoides/farmacologia , Manilkara/química , Extratos Vegetais/farmacologia , Taninos/farmacologia , Trichomonas vaginalis/efeitos dos fármacos , Tritrichomonas foetus/efeitos dos fármacos , Antitricômonas/química , Antitricômonas/isolamento & purificação , Brasil , Linhagem Celular , Sobrevivência Celular , Cromatografia Líquida , Células Epiteliais/efeitos dos fármacos , Flavonoides/química , Flavonoides/isolamento & purificação , Células HeLa , Humanos , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Taninos/química , Taninos/isolamento & purificação , Trichomonas vaginalis/fisiologia , Tritrichomonas foetus/fisiologia
15.
Molecules ; 22(9)2017 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-28858260

RESUMO

The plant family Amaryllidaceae is well-known for its unique alkaloid constituents, which exhibit a wide range of biological activities. Its representative, Amaryllis belladonna, has a geographical distribution covering mainly southern Africa, where it has significant usage in the traditional medicine of the native people. In this study, A. belladonna samples collected in Brazil were examined for alkaloid content. Alkaloid profiles of A. belladonna bulbs were generated by a combination of chromatographic, spectroscopic and spectrometric methods, including GC-MS and 2D NMR. In vitro screening against four different parasitic protozoa (Trypanosoma cruzi, T. brucei rhodesiense, Leishmania donovani and Plasmodium falciparum) was carried out using the A. belladonna crude methanol extract, as well as three of its alkaloid isolates. Twenty-six different Amaryllidaceae alkaloids were identified in the A. belladonna bulb samples, and three of them were isolated. Evidence for their respective biosynthetic pathways was afforded via their mass-spectral fragmentation data. Improved data for 1-O-acetylcaranine was provided by 2D NMR experiments, together with new ¹H-NMR data for buphanamine. The crude extract and 3-O-acetylhamayne exhibited good antiprotozoal activity in vitro, although both with a high cytotoxic index.


Assuntos
Alcaloides de Amaryllidaceae/química , Amaryllidaceae/química , Antiprotozoários/química , Extratos Vegetais/química , Alcaloides de Amaryllidaceae/isolamento & purificação , Alcaloides de Amaryllidaceae/farmacologia , Antiprotozoários/isolamento & purificação , Antiprotozoários/farmacologia , Vias Biossintéticas , Leishmania donovani/efeitos dos fármacos , Testes de Sensibilidade Parasitária , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Trypanosoma cruzi/efeitos dos fármacos
16.
Molecules ; 22(12)2017 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-29232852

RESUMO

The Amaryllidaceae family has proven to be a rich source of active compounds, which are characterized by unique skeleton arrangements and a broad spectrum of biological activities. The aim of this work was to perform the first detailed study of the alkaloid constituents of Hippeastrum reticulatum (Amaryllidaceae) and to determine the anti-parasitological and cholinesterase (AChE and BuChE) inhibitory activities of the epimers (6α-hydroxymaritidine and 6ß-hydroxymaritidine). Twelve alkaloids were identified in H. reticulatum: eight known alkaloids by GC-MS and four unknown (6α-hydroxymaritidine, 6ß-hydroxymaritidine, reticulinine and isoreticulinine) by NMR. The epimer mixture (6α-hydroxymaritidine and 6ß-hydroxymaritidine) showed low activity against all protozoan parasites tested and weak AChE-inhibitory activity. Finally, a molecular docking analysis of AChE and BuChE proteins showed that isoreticulinine may be classified as a potential inhibitory molecule since it can be stabilized in the active site through hydrogen bonds, π-π stacking and hydrophobic interactions.


Assuntos
Alcaloides/química , Amaryllidaceae/química , Antiparasitários/química , Inibidores da Colinesterase/química , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Alcaloides/farmacologia , Antiparasitários/farmacologia , Butirilcolinesterase/química , Butirilcolinesterase/metabolismo , Domínio Catalítico/efeitos dos fármacos , Inibidores da Colinesterase/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Ligação de Hidrogênio/efeitos dos fármacos , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia
17.
Bioorg Med Chem Lett ; 26(9): 2229-36, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-27020521

RESUMO

Trichomonas vaginalis causes trichomoniasis; the most common but overlooked non-viral sexually transmitted disease worldwide. The treatment is based at 5'-nitroimidazoles, however, failure are related to resistance of T. vaginalis to chemotherapy. Caatinga is a uniquely Brazilian region representing a biome with type desert vegetation and plants present diverse biological activity, however, with few studies. The aim of this study was to investigate the activity against T. vaginalis of different plants from Caatinga and identify the compounds responsible by the activity. A bioguided fractionation of Manilkara rufula was performed and four major compounds were identified: caproate of α-amyrin (1b), acetate of ß-amyrin (2a), caproate of ß-amyrin (2b), and acetate of lupeol (3a). In addition, six derivatives of α-amyrin (1), ß-amyrin (2) and lupeol (3) were synthesized and tested against the parasite. Ursolic acid (5) reduced about 98% of parasite viability after 2h of incubation and drastic ultrastructural alterations were observed by scanning electron microscopy. Moreover, 5 presented high cytotoxicity to HMVII and HeLa cell line and low cytotoxicity against Vero line at 50 µM (MIC against the parasite). Metronidazole effect against T. vaginalis resistant isolate was improved when in association with 5.


Assuntos
Extratos Vegetais/farmacologia , Plantas Medicinais/química , Trichomonas vaginalis/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Plantas Medicinais/classificação
18.
J Nat Prod ; 79(5): 1241-8, 2016 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-27096334

RESUMO

Two new alkaloids, 4-O-methylnangustine (1) and 7-hydroxyclivonine (2) (montanine and homolycorine types, respectively), and four known alkaloids were isolated from the bulbs of Hippeastrum argentinum, and their cholinesterase-inhibitory activities were evaluated. These compounds were identified using GC-MS, and their structures were defined by physical data analysis. Compound 2 showed weak butyrylcholinesterase (BuChE)-inhibitory activity, with a half-maximal inhibitory concentration (IC50) value of 67.3 ± 0.09 µM. To better understand the experimental results, a molecular modeling study was also performed. The combination of a docking study, molecular dynamics simulations, and quantum theory of atoms in molecules calculations provides new insight into the molecular interactions of compound 2 with BuChE, which were compared to those of galantamine.


Assuntos
Alcaloides de Amaryllidaceae/farmacologia , Butirilcolinesterase/efeitos dos fármacos , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/isolamento & purificação , Argentina , Cromatografia Gasosa-Espectrometria de Massas , Concentração Inibidora 50 , Modelos Moleculares , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química
19.
Chem Biodivers ; 12(8): 1184-99, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26265570

RESUMO

In this article, we report on the alkaloid profile and dynamic of alkaloid content and diversity in two Narcissus plants at different stages of development. The alkaloid profile of the two Narcissus species was investigated by GC/MS and HPTLC. Fifty eight Amaryllidaceae alkaloids were detected, and 25 of them were identified in the different organs of N. tazetta and N. papyraceus. The alkaloid 3-O-methyl-9-O-demethylmaritidine is tentatively identified here for the first time from the Amaryllidaceae family, and four alkaloids (tazettamide, sternbergine, 1-O-acetyllycorine, 2,11-didehydro-2-dehydroxylycorine) are tentatively identified for the first time in the genus Narcissus. The different organs of the two species analyzed showed remarkable differences in their alkaloid pattern, type of biosynthesis, main alkaloid and number of alkaloids. Lycorine-type alkaloids dominated the alkaloid, metabolism in N. papyraceus, while alkaloids of narciclasine-, galanthamine- and homolycorine-types were found only in the species N. tazetta L.


Assuntos
Alcaloides/análise , Narcissus/química , Extratos Vegetais/química , Cromatografia em Camada Fina , Cromatografia Gasosa-Espectrometria de Massas
20.
Z Naturforsch C J Biosci ; 79(3-4): 73-79, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38516999

RESUMO

The Sceletium-type alkaloids, known for their anxiolytic and antidepressant activities, have been recently found to be biosynthesized in Narcissus cv. Hawera, which is largely used as an ornamental plant. An alkaloid fraction enriched with Sceletium-type alkaloids from the plant has shown promising antidepressant and anxiolytic activities. In the present study, qualitative and quantitative analyses of the alkaloids in the plant organs were performed during one vegetation season by GC-MS. The alkaloid pattern and total alkaloid content was found to depend strongly on the stage of development and plant organ. The alkaloid content of bulbs was found to be highest during the dormancy period and lowest in sprouting bulbs. The leaves showed the highest alkaloid content during the intensive vegetative growth and lowest during flowering. In total, 13 alkaloids were detected in the methanol extracts of Narcissus cv. Hawera, six Sceletium-type and seven typical Amaryllidaceae alkaloids. Major alkaloids in the alkaloid pattern were lycorine, 6-epi-mesembrenol, mesembrenone, sanguinine, and galanthamine. The leaves of flowering plants were found to have the highest amount of 6-epi-mesembrenol. Mesembrenone was found to be dominant alkaloid in the leaves of sprouting bulbs and in the flowers. Considering the biomass of the plant, the dormant bulbs are the best source of alkaloid fractions enriched with 6-epi-mesembrenol. The flowers and the young leaves can be used for preparation of alkaloid fractions enriched with mesembrenone. The results indicates that Narcissus cv. Hawera is an emerging source of valuable bioactive compounds and its utilization can be extended as a medicinal plant.


Assuntos
Alcaloides , Alcaloides Indólicos , Narcissus , Fenantridinas , Folhas de Planta , Narcissus/química , Narcissus/metabolismo , Narcissus/crescimento & desenvolvimento , Alcaloides/metabolismo , Alcaloides/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Flores/química , Flores/metabolismo , Flores/crescimento & desenvolvimento , Extratos Vegetais/química , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Alcaloides de Amaryllidaceae/metabolismo , Alcaloides de Amaryllidaceae/química
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