RESUMEN
Three new isoaigialones, A, B, and C (1-3), along with aigialone (4), were isolated from the crude EtOAc extract of a Phaeoacremonium sp., an endophytic fungus obtained from the leaves of Senna spectabilis. The structures of these compounds were elucidated based on the analysis of spectroscopic data. Compounds 2 and 4 were active against the phytopathogenic fungi Cladosporium cladosporioides and C. sphaerospermum. This is the first report of metabolites produced by an Phaeoacremonium sp., associated with S. spectabilis.
Asunto(s)
Acetales/aislamiento & purificación , Acetales/farmacología , Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Ascomicetos/química , Cladosporium/química , Cetonas/aislamiento & purificación , Cetonas/farmacología , Lactonas/aislamiento & purificación , Hojas de la Planta/química , Senna/química , Acetales/química , Antifúngicos/química , Cetonas/química , Lactonas/química , Lactonas/metabolismo , Lactonas/farmacología , Estructura MolecularRESUMEN
This study aimed at assessing the chemical composition of the essential oils from leaves and fruits of Conchocarpus fontanesianus, an endemic Brazilian species of Rutaceae. The plant material was harvested from two regions of the Atlantic rainforest in the State of São Paulo. The volatile compounds in the essential oils were extracted by hydrodistillation (HD), and analyzed by GC/FID and GC/MS, allowing the quantification and identification of 54 components in total, which comprise about 97% of the total oil composition. From the leaves collected in Caraguatatuba and Juréia-Itatins, the major volatile compounds identified were as follows: spathulenol (22.32% and 16.67%) and α-cadinol (9.7% and 14.76%). However, ß-myrcene (34.56%), (+)-epi-bicyclosesquiphellandrene (8.71%), and bicyclogermacrene (5.80%) were dominant in the fruits collected only in Juréia-Itatins. The in vitro biological activities were tested to evaluate the cytotoxic, antifungal, and antioxidant potential of essential oils from leaves and fruits.
Asunto(s)
Antifúngicos/farmacología , Antineoplásicos Fitogénicos/farmacología , Cladosporium/efectos de los fármacos , Aceites Volátiles/química , Aceites Volátiles/farmacología , Rutaceae/química , Antifúngicos/análisis , Antifúngicos/química , Antineoplásicos Fitogénicos/análisis , Antineoplásicos Fitogénicos/química , Brasil , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Frutas/química , Humanos , Células MCF-7 , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Aceites Volátiles/análisis , Hojas de la Planta/química , Relación Estructura-ActividadRESUMEN
Bioactivity-guided fractionation of the EtOH extract of the branches of Kielmeyera variabilis led to the isolation of a new acylphoroglucinol (1), which was active against all the MRSA strains tested herein, with pronounced activity against strain EMRSA-16. Compound 1 displayed an MIC of 0.5 mg/L as compared with an MIC of 128 mg/L for the control antibiotic norfloxacin. The structure of the new compound was elucidated by 1D and 2D NMR spectroscopic analysis and mass spectrometry, and experimental and calculated ECD were used to determine the absolute configurations. The compounds ß-sitosterol (2), stigmasterol (3), ergost-5-en-3-ol (4), and osajaxanthone (5) also occurred in the n-hexane fraction. The EtOAc fraction contained nine known xanthones: 3,6-dihydroxy-1,4,8-trimethoxyxanthone (6), 3,5-dihydroxy-4-methoxyxanthone (7), 3,4-dihydroxy-6,8-dimethoxyxanthone (8), 3,4-dihydroxy-2-methoxyxanthone (9), 5-hydroxy-1,3-dimethoxyxanthone (10), 4-hydroxy-2,3-dimethoxyxanthone (11), kielcorin (12), 3-hydroxy-2-methoxyxanthone (13), and 2-hydroxy-1-methoxyxanthone (14), which showed moderate to low activity against the tested MRSA strains.
Asunto(s)
Antibacterianos , Clusiaceae/química , Floroglucinol , Staphylococcus aureus/efectos de los fármacos , Xantonas , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Brasil , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Floroglucinol/análogos & derivados , Floroglucinol/química , Floroglucinol/aislamiento & purificación , Floroglucinol/farmacología , Componentes Aéreos de las Plantas/química , Estereoisomerismo , Xantonas/química , Xantonas/aislamiento & purificación , Xantonas/farmacologíaRESUMEN
Bioactivity-guided fractionation of the separate CH2Cl2 extracts from the aerial parts of Peperomia alata and P. trineura yielded seven polyketides: alatanone A [3-hydroxy-2-(5'-phenylpent-4'E-enoyl)cyclohex-2-en-1-one, 1a] and alatanone B [3-hydroxy-2-(3'-phenyl-6'-methylenedioxypropanoyl)cyclohex-2-en-1-one, 2a] from P. alata and trineurone A [3-hydroxy-2-(11'-phenylundec-10'E-enoyl)cyclohex-2-en-1-one, 1b], trineurone B [3-hydroxy-2-(15'-phenyl-18'-methylenedioxypentadecanoyl)cyclohex-2-en-1-one, 2b], trineurone C [3-hydroxy-2-(17'-phenyl-20'-methylenedioxyheptadecanoyl)cyclohex-2-en-1-one, 2c], trineurone D [3-hydroxy-2-(hexadec-10'Z-enoyl)cyclohex-2-en-1-one, 3a], and trineurone E [(6R)-(+)-3,6-dihydroxy-2-(hexadec-10'Z-enoyl)cyclohex-2-en-1-one, 3b] from P. trineura. The isolated compounds were evaluated for antifungal activity against Cladosporium cladosporioides and C. sphaeospermum and for cytotoxicity against the K562 and Nalm-6 leukemia cell lines.
Asunto(s)
Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Piperaceae/química , Policétidos/aislamiento & purificación , Policétidos/farmacología , Antifúngicos/química , Brasil , Cladosporium/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Células K562 , Pruebas de Sensibilidad Microbiana , Resonancia Magnética Nuclear Biomolecular , Policétidos/químicaRESUMEN
The chemical compositions and antimicrobial activities of essential oils from the leaves, stems, capitula, and cypselas of Chromolaena laevigata were evaluated at two different phenological stages, flowering and fruiting. Thirty-eight compounds were identified in the crude oils by GC/MS. The sesquiterpene laevigatin was the major constituent of the leaf, capitulum, and cypsela oils, while the sesquiterpene spathulenol was the main component in the stem oils. The antimicrobial activities of the oils were evaluated against Candida albicans, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Stem oil obtained from Chromolaena laevigata during the fruiting stage generally showed the highest activity with minimum inhibitory concentration (MIC) values of 62.5â µg/ml against Candida albicans and S. aureus, and 500â µg/ml against P. aeruginosa and E. coli. Pure laevigatin exhibited MIC values of 500 and 125â µg/ml against C. albicans and S. aureus, respectively, indicating that this constituent could be responsible, at least in part, for the antimicrobial activities detected in the crude oils. More studies concerning the biological activities of isolated derivatives are required to improve our knowledge of the antimicrobial potential of volatile compounds present in native plants.
Asunto(s)
Antiinfecciosos/química , Chromolaena/química , Aceites Volátiles/química , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Candida albicans/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/aislamiento & purificación , Aceites Volátiles/farmacología , Hojas de la Planta/química , Tallos de la Planta/química , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacosRESUMEN
Conchocarpus fontanesianus (A. St.-Hill.) Kallunki & Pirani, Rutaceae, popularly known as pitaguará, is a native and endemic tree from São Paulo and Rio de Janeiro States, Brazil. Based in the information that anticholinesterasic derivatives could act as new prototypes to treatment of Alzheimer disease, this work describes the fractionation guided by evaluation of the anticholinesterase activity of the ethanolic stems extract from C. fontanesianus. This procedure afforded the alkaloids dictamnine (1), γ-fagarine (2), skimianine (3), and 2-phenyl-1-methyl-4-quinolone (4), as well as the coumarin marmesin (5).
RESUMEN
As part of an ongoing research project on Senna and Cassia species, five new pyridine alkaloids, namely, 12'-hydroxy-7'-multijuguinol (1), 12'-hydroxy-8'-multijuguinol (2), methyl multijuguinate (3), 7'-multijuguinol (4), and 8'-multijuguinol (5), were isolated from the leaves of Senna multijuga (syn. Cassiamultijuga). Their structures were elucidated on the basis of spectroscopic data analysis. Mass spectrometry was used for confirmation of the positions of the hydroxy groups in the side-chains of 1, 2, 4, and 5. All compounds exhibited weak in vitro acetylcholinesterase inhibitory activity as compared with the standard compound physostigmine.
Asunto(s)
Alcaloides/aislamiento & purificación , Alcaloides/farmacología , Inhibidores de la Colinesterasa/aislamiento & purificación , Inhibidores de la Colinesterasa/farmacología , Piridinas/aislamiento & purificación , Piridinas/farmacología , Senna/química , Alcaloides/química , Brasil , Inhibidores de la Colinesterasa/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Fisostigmina/farmacología , Hojas de la Planta/química , Piridinas/químicaRESUMEN
Two unusual pyridine alkaloids, 7'-multijuguinone (1) and 12'-hydroxy-7'-multijuguinone (2), were isolated from the leaves of Senna multijuga, together with the known flavonoid rutin. The structures of the new alkaloids were established on the basis of spectroscopic data interpretation. Compounds 1 and 2 exhibited moderate in vitro acetylcholinesterase (AChE) inhibitory activity, in comparison with the standard compound physostigmine.
Asunto(s)
Acetilcolinesterasa/metabolismo , Alcaloides/aislamiento & purificación , Alcaloides/farmacología , Inhibidores de la Colinesterasa/aislamiento & purificación , Inhibidores de la Colinesterasa/farmacología , Plantas Medicinales/química , Piridinas/aislamiento & purificación , Piridinas/farmacología , Senna/química , Alcaloides/química , Brasil , Inhibidores de la Colinesterasa/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Hojas de la Planta/química , Piridinas/químicaRESUMEN
In the course of our continuous search for bioactive metabolites from endophytic fungi living in plants from the Brazilian flora, leaves of Alibertia macrophylla (Rubiaceae) were submitted to isolation of endophytes, and two species of Penicillium were isolated. The acetonitrile fraction obtained in corn from a culture of Penicillium sp. 1 afforded orcinol (1). On the other hand, Penicillium sp. 1 cultivated in potato-dextrose-broth furnished two different compounds, cyclo-(L-Pro-L-Val) (2) and uracil (3). The chromatographic fractionation of the acetonitrile fraction obtained from Penicillium sp. 2 led to three dihydroisocoumarins, 4-hydroxymellein (4), 8-methoxymellein (5) and 5-hydroxymellein (6). Compounds 5 and 6 were obtained from the Penicillium genus for the first time. Additionally, metabolites 1-6 were evaluated for their antifungal and acetylcholinesterase (AChE) inhibitory activities. The most active compounds 1 and 4 exhibited detection limits of 5.00 and 10.0 microg against Cladosporium cladosporioides and C. sphaerospermum, respectively. Compound 2 showed a detection limit of 10.0 microg, displaying potent AChE inhibitory activity.
Asunto(s)
Penicillium/química , Penicillium/metabolismo , Rubiaceae/química , Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Brasil , Inhibidores de la Colinesterasa/aislamiento & purificación , Inhibidores de la Colinesterasa/farmacología , Espectroscopía de Resonancia Magnética/métodos , Modelos Moleculares , Ocratoxinas/química , Ocratoxinas/aislamiento & purificación , Penicillium/efectos de los fármacos , Penicillium/aislamiento & purificación , Rubiaceae/microbiología , Solanum tuberosum/microbiología , Espectrofotometría , Zea mays/microbiologíaRESUMEN
Five new piperidine alkaloids were designed from natural (-)-3-O-acetyl-spectaline and (-)-spectaline that were obtained from the flowers of Senna spectabilis (sin. Cassia spectabilis, Leguminosae). Two semi-synthetic analogues (7 and 9) inhibited rat brain acetylcholinesterase, showing IC50 of 7.32 and 15.1 microM, and were 21 and 9.5 times less potent against rat brain butyrylcholinesterase, respectively. Compound 9 (1mg/kg, i.p.) was fully efficacious in reverting scopolamine-induced amnesia in mice. The two active compounds (7 and 9) did not show overt toxic effects at the doses tested in vivo.