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1.
Int J Mol Sci ; 24(21)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37958488

RESUMO

Aristotelia chilensis or "maqui" is a tree native to Chile used in the folk medicine of the Mapuche people as an anti-inflammatory agent for the treatment of digestive ailments, fever, and skin lesions. Maqui fruits are black berries which are considered a "superfruit" with notable potential health benefits, promoted to be an antioxidant, cardioprotective, and anti-inflammatory. Maqui leaves contain non-iridoid monoterpene indole alkaloids which have previously been shown to act on nicotinic acetylcholine receptors, potassium channels, and calcium channels. Here, we isolated a new alkaloid from maqui leaves, now called makomakinol, together with the known alkaloids aristoteline, hobartine, and 3-formylindole. Moreover, the polyphenols quercetine, ethyl caffeate, and the terpenes, dihydro-ß-ionone and terpin hydrate, were also obtained. In light of the reported analgesic and anti-nociceptive properties of A. chilensis, in particular a crude mixture of alkaloids containing aristoteline and hobartinol (PMID 21585384), we therefore evaluated the activity of aristoteline and hobartine on NaV1.8, a key NaV isoform involved in nociception, using automated whole-cell patch-clamp electrophysiology. Aristoteline and hobartine both inhibited Nav1.8 with an IC50 of 68 ± 3 µM and 54 ± 1 µM, respectively. Hobartine caused a hyperpolarizing shift of the voltage-dependence of the activation, whereas aristoteline did not change the voltage-dependence of the activation or inactivation. The inhibitory activity of these alkaloids on NaV channels may contribute to the reported analgesic properties of Aristotelia chilensis used by the Mapuche people.


Assuntos
Alcaloides , Elaeocarpaceae , Humanos , Alcaloides/farmacologia , Alcaloides Indólicos , Extratos Vegetais/farmacologia , Analgésicos/farmacologia , Anti-Inflamatórios
2.
Molecules ; 28(7)2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37049851

RESUMO

There are high mortality and morbidity rates from poisonous snakebites globally. Many medicinal plants are locally used for snakebite treatment in Uganda. This study aimed to determine the in vitro anti-venom activities of aqueous extract and oils of Toona ciliata against Naja melanoleuca venom. A mixture of venom and extract was administered intramuscularly in rats. Anticoagulant, antiphospholipase A2 (PLA2) inhibition assay, and gel electrophoresis for anti-venom activities of oils were done. The chemical constituents of the oils of ciliata were identified using Gas chromatography-tandem mass spectroscopy (GC-MS/MS). The LD50 of the venom was 0.168 ± 0.21 µg/g. The venom and aqueous extract mixture (1.25 µg/g and 3.5 mg/g) did not cause any rat mortality, while the control with venom only (1.25 µg/g) caused death in 1 h. The aqueous extract of T. ciliata inhibited the anticoagulation activity of N. melanoleuca venom from 18.58 min. to 4.83 min and reduced the hemolytic halo diameter from 24 to 22 mm. SDS-PAGE gel electrophoresis showed that oils completely cleared venom proteins. GC-MS/MS analysis showed that the oils had sesquiterpene hydrocarbons (60%) in the volatile oil (VO) and oxygenated sesquiterpenes (48.89%) in the non-volatile oils (NVO). Some major compounds reported for the first time in T. ciliata NVOs were: Rutamarin (52.55%), ß-Himachalol (9.53%), Girinimbine (6.68%) and Oprea1 (6.24%). Most compounds in the VO were reported for the first time in T. ciliata, including the major ones Santalene (8.55%) and Himachal-7-ol (6.69%). The result showed that aqueous extract and oils of T. ciliata have anti-venom/procoagulant activities and completely neutralized the venom. We recommend a study on isolation and testing the pure compounds against the same venom.


Assuntos
Antivenenos , Óleos Voláteis , Ratos , Animais , Antivenenos/farmacologia , Venenos Elapídicos/análise , Toona , Espectrometria de Massas em Tandem , Óleos Voláteis/farmacologia , Água
3.
Int J Mol Sci ; 23(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36361785

RESUMO

Fungal biotransformation is an attractive synthetic strategy to produce highly specific compounds with chemical functionality in regions of the carbon skeleton that are not easily activated by conventional organic chemistry methods. In this work, Cladosporium antarcticum isolated from sediments of Glacier Collins in Antarctica was used to obtain novel drimane sesquiterpenoids alcohols with activity against Candida yeast from drimendiol and epidrimendiol. These compounds were produced by the high-yield reduction of polygodial and isotadeonal with NaBH4 in methanol. Cladosporium antarcticum produced two major products from drimendiol, identified as 9α-hydroxydrimendiol (1, 41.4 mg, 19.4% yield) and 3ß-hydroxydrimendiol (2, 74.8 mg, 35% yield), whereas the biotransformation of epidrimendiol yielded only one product, 9ß-hydroxyepidrimendiol (3, 86.6 mg, 41.6% yield). The products were purified by column chromatography and their structure elucidated by NMR and MS. The antifungal activity of compounds 1-3 was analyzed against Candida albicans, C. krusei and C. parapsilosis, showing that compound 2 has a MIC lower than 15 µg/mL against the three-pathogenic yeast. In silico studies suggest that a possible mechanism of action for the novel compounds is the inhibition of the enzyme lanosterol 14α-demethylase, affecting the ergosterol synthesis.


Assuntos
Álcoois , Sesquiterpenos , Álcoois/metabolismo , Candida , Antifúngicos/química , Sesquiterpenos/química , Candida albicans , Biotransformação , Testes de Sensibilidade Microbiana
4.
Int J Mol Sci ; 23(19)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36233069

RESUMO

Drimys winteri J.R. (Winteraceae) produce drimane sesquiterpenoids with activity against Candida yeast. In this work, drimenol, polygodial (1), isotadeonal (2), and a new drimane α,ß-unsaturated 1,4-dialdehyde, named winterdial (4), were purified from barks of D. winteri. The oxidation of drimenol produced the monoaldehyde drimenal (3). These four aldehyde sesquiterpenoids were evaluated against six Candida species isolated from candidemia patients in Chilean hospitals. Results showed that 1 displays fungistatic activity against all yeasts (3.75 to 15.0 µg/mL), but irritant effects on eyes and skin, whereas its non-pungent epimer 2 has fungistatic and fungicide activities at 1.9 and 15.0 µg/mL, respectively. On the other hand, compounds 3 and 4 were less active. Molecular dynamics simulations suggested that compounds 1-4 are capable of binding to the catalytic pocket of lanosterol 14-alpha demethylase with similar binding free energies, thus suggesting a potential mechanism of action through the inhibition of ergosterol synthesis. According to our findings, compound 2 appears as a valuable molecular scaffold to pursue the future development of more potent drugs against candidiasis with fewer side effects than polygodial. These outcomes are significant to broaden the alternatives to treat fungal infections with increasing prevalence worldwide using natural compounds as a primary source for active compounds.


Assuntos
Candidemia , Fungicidas Industriais , Sesquiterpenos , Aldeídos/farmacologia , Candida , Chile , Ergosterol , Humanos , Irritantes , Lanosterol , Sesquiterpenos Policíclicos , Sesquiterpenos/química
5.
J Nat Prod ; 83(8): 2390-2398, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32790306

RESUMO

Five new compounds-rhodimer (1), rhodiflavan A (2), rhodiflavan B (3), rhodiflavan C (4), and rhodacarpin (5)-along with 16 known secondary metabolites, were isolated from the CH2Cl2-CH3OH (1:1) extract of the roots of Tephrosia rhodesica. They were identified by NMR spectroscopic, mass spectrometric, X-ray crystallographic, and ECD spectroscopic analyses. The crude extract and the isolated compounds 2-5, 9, 15, and 21 showed activity (100% at 10 µg and IC50 = 5-15 µM) against the chloroquine-sensitive (3D7) strain of Plasmodium falciparum.


Assuntos
Flavonoides/isolamento & purificação , Raízes de Plantas/química , Tephrosia/química , Antimaláricos/farmacologia , Cristalografia por Raios X , Flavonoides/química , Flavonoides/farmacologia , Estrutura Molecular , Plasmodium falciparum/efeitos dos fármacos , Prenilação , Análise Espectral
6.
Molecules ; 25(11)2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32481689

RESUMO

The synthesis of new phenanthr[9,10-e][1,3]oxazines was achieved by the direct coupling of 9-phenanthrol with cyclic imines in the modified aza-Friedel-Crafts reaction followed by the ring closure of the resulting bifunctional aminophenanthrols with formaldehyde. Aminophenanthrol-type Mannich bases were synthesised and transformed to phenanthr[9,10-e][1,3]oxazines via [4 + 2] cycloaddition. Detailed NMR structural analyses of the new polyheterocycles as well as conformational studies including Density Functional Theory (DFT) modelling were performed. The relative stability of ortho-quinone methides (o-QMs) was calculated, the geometries obtained were compared with the experimentally determined NMR structures, and thereby, the regioselectivity of the reactions has been assigned.


Assuntos
Indolquinonas/química , Catálise , Formaldeído/química , Iminas/química , Espectroscopia de Ressonância Magnética , Conformação Molecular , Estrutura Molecular , Estereoisomerismo
7.
J Nat Prod ; 81(4): 811-817, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29634269

RESUMO

The drimane sesquiterpenoids drimenin, cinnamolide, dendocarbin A, and polygodial were purified from the Canelo tree ( Drimys winteri) and chemically characterized by spectroscopic methods. The pharmacological activity of these natural compounds were determined on hα4ß2, hα3ß4, and hα7 nicotinic acetylcholine receptors (AChRs) by Ca2+ influx measurements. The results established that drimane sesquiterpenoids inhibit AChRs with the following selectivity: hα4ß2 > hα3ß4 > hα7. In the case of hα4ß2 AChRs, the following potency rank order was determined (IC50's in µM): drimenin (0.97 ± 0.35) > cinnamolide (1.57 ± 0.36) > polygodial (62.5 ± 19.9) ≫ dendocarbin A (no activity). To determine putative structural features underlying the differences in inhibitory potency at hα4ß2 AChRs, additional structure-activity relationship and molecular docking experiments were performed. The Ca2+ influx and structural results supported a noncompetitive mechanism of inhibition, where drimenin interacted with luminal and nonluminal (TMD-ß2 intrasubunit) sites. The structure-activity relationship results, i.e., the lower the ligand polarity, the higher the inhibitory potency, supported the nonluminal interaction. Ligand binding to both sites might inhibit the hα4ß2 AChR by a cooperative mechanism, as shown experimentally ( nH > 1). Drimenin could be used as a molecular scaffold for the development of more potent inhibitors with higher selectivity for the hα4ß2 AChR.


Assuntos
Receptores Nicotínicos/metabolismo , Sesquiterpenos/farmacologia , Terpenos/farmacologia , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Sítios de Ligação , Linhagem Celular , Células HEK293 , Humanos , Ligantes , Simulação de Acoplamento Molecular/métodos , Sesquiterpenos Policíclicos , Relação Estrutura-Atividade
8.
J Nat Prod ; 80(7): 2060-2066, 2017 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-28665590

RESUMO

A new isoflavone, 8-prenylmilldrone (1), and four new rotenoids, oblarotenoids A-D (2-5), along with nine known compounds (6-14), were isolated from the CH2Cl2/CH3OH (1:1) extract of the leaves of Millettia oblata ssp. teitensis by chromatographic separation. The purified compounds were identified by NMR spectroscopic and mass spectrometric analyses, whereas the absolute configurations of the rotenoids were established on the basis of chiroptical data and in some cases by single-crystal X-ray crystallography. Maximaisoflavone J (11) and oblarotenoid C (4) showed weak activity against the human breast cancer cell line MDA-MB-231 with IC50 values of 33.3 and 93.8 µM, respectively.


Assuntos
Isoflavonas/isolamento & purificação , Millettia/química , Folhas de Planta/química , Rotenona/isolamento & purificação , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Isoflavonas/química , Isoflavonas/farmacologia , Quênia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Rotenona/química , Rotenona/farmacologia
9.
BMC Complement Altern Med ; 17(1): 167, 2017 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-28340622

RESUMO

BACKGROUND: Malaria is an old life-threatening parasitic disease that is still affecting many people, mainly children living in sub-Saharan Africa. Availability of effective antimalarial drugs played a significant role in the treatment and control of malaria. However, recent information on the emergence of P. falciparum parasites resistant to one of the artemisinin-based combination therapies suggests the need for discovery of new drug molecules. Therefore, this study aimed to evaluate the antiplasmodial activity of extracts, fractions and isolated compound from medicinal plants traditionally used in the treatment of malaria in Tanzania. METHODS: Dry powdered plant materials were extracted by cold macerations using different solvents. Norcaesalpin D was isolated by column chromatography from dichloromethane root extract of Caesalpinia bonducella and its structure was assigned based on the spectral data. Crude extracts, fractions and isolated compound were evaluated for antiplasmodial activity against chloroquine-sensitive P. falciparum (3D7), chloroquine-resistant P. falciparum (Dd2, K1) and artemisinin-resistant P. falciparum (IPC 5202 Battambang, IPC 4912 Mondolkiri) strains using the parasite lactate dehydrogenase assay. RESULTS: The results indicated that extracts of Erythrina schliebenii, Holarrhena pubescens, Dissotis melleri and C. bonducella exhibited antiplasmodial activity against Dd2 parasites. Ethanolic root extract of E. schliebenii had an IC50 of 1.87 µg/mL while methanolic and ethanolic root extracts of H. pubescens exhibited an IC50 = 2.05 µg/mL and IC50 = 2.43 µg/mL, respectively. Fractions from H. pubescens and C. bonducella roots were found to be highly active against K1, Dd2 and artemisinin-resistant parasites. Norcaesalpin D from C. bonducella root extract was active with IC50 of 0.98, 1.85 and 2.13 µg/mL against 3D7, Dd2 and IPC 4912-Mondolkiri parasites, respectively. CONCLUSIONS: Antiplasmodial activity of norcaesalpin D and extracts of E. schliebenii, H. pubescens, D. melleri and C. bonducella reported in this study requires further attention for the discovery of antimalarial lead compounds for future drug development.


Assuntos
Antimaláricos/farmacologia , Diterpenos/farmacologia , Malária/parasitologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Antimaláricos/química , Antimaláricos/isolamento & purificação , Diterpenos/química , Diterpenos/isolamento & purificação , Humanos , Malária/tratamento farmacológico , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/fisiologia , Tanzânia
10.
Magn Reson Chem ; 55(12): 1073-1078, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28665001

RESUMO

The conformational equilibrium of the axial/equatorial conformers of 4-methylene-cyclohexyl pivalate is studied by dynamic NMR spectroscopy in a methylene chloride/freon mixture. At 153 K, the ring interconversion gets slow on the nuclear magnetic resonance timescale, the conformational equilibrium (-ΔG°) can be examined, and the barrier to ring interconversion (ΔG# ) can be determined. The structural influence of sp2 hybridization on both ΔG° and ΔG# of the cyclohexyl moiety can be quantified.

11.
Molecules ; 22(2)2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28230755

RESUMO

In our search for new antiplasmodial agents, the CH2Cl2/CH3OH (1:1) extract of the roots of Tephrosia aequilata was investigated, and observed to cause 100% mortality of the chloroquine-sensitive (3D7) strain of Plasmodium falciparum at a 10 mg/mL concentration. From this extract three new chalconoids, E-2',6'-dimethoxy-3',4'-(2'',2''-dimethyl)pyranoretrochalcone (1, aequichalcone A), Z-2',6'-dimethoxy-3',4'-(2'',2''-dimethyl)pyranoretrochalcone (2, aequichalcone B), 4''-ethoxy-3''-hydroxypraecansone B (3, aequichalcone C) and a new pterocarpene, 3,4:8,9-dimethylenedioxy-6a,11a-pterocarpene (4), along with seven known compounds were isolated. The purified compounds were characterized by NMR spectroscopic and mass spectrometric analyses. Compound 1 slowly converts into 2 in solution, and thus the latter may have been enriched, or formed, during the extraction and separation process. The isomeric compounds 1 and 2 were both observed in the crude extract. Some of the isolated constituents showed good to moderate antiplasmodial activity against the chloroquine-sensitive (3D7) strain of Plasmodium falciparum.


Assuntos
Chalconas/química , Extratos Vegetais/química , Raízes de Plantas/química , Pterocarpanos/química , Tephrosia/química , Antimaláricos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
12.
J Nat Prod ; 78(12): 2932-9, 2015 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-26651537

RESUMO

Five new compounds, 4-O-geranylisoliquiritigenin (1), 12-dihydrousararotenoid B (2), 12-dihydrousararotenoid C (3), 4'-O-geranyl-7-hydroxyflavanone (4), and 4'-O-geranyl-7-hydroxydihydroflavanol (5), along with 12 known natural products (6-17) were isolated from the CH2Cl2/MeOH (1:1) extract of the root bark of Millettia usaramensis ssp. usaramensis by chromatographic separation. The purified metabolites were identified by NMR spectroscopic and mass spectrometric analyses, whereas their absolute configurations were established on the basis of chiroptical data and in some cases also by X-ray crystallography. The crude extract was moderately active (IC50 = 11.63 µg/mL) against the ER-negative MDB-MB-231 human breast cancer cell line, and accordingly compounds 6, 8, 9, 10, 12, and 16 also showed moderate to low cytotoxic activities (IC50 25.7-207.2 µM). The new natural product 1 exhibited antiplasmodial activity with IC50 values of 3.7 and 5.3 µM against the chloroquine-sensitive 3D7 and the chloroquine-resistant Dd2 Plasmodium falciparum strains, respectively, and was also cytotoxic to the HEK293 cell line.


Assuntos
Antimaláricos/isolamento & purificação , Chalconas/isolamento & purificação , Flavonoides/isolamento & purificação , Millettia/química , Antimaláricos/química , Antimaláricos/farmacologia , Chalconas/química , Chalconas/farmacologia , Cloroquina/farmacologia , Cristalografia por Raios X , Flavanonas , Flavonoides/química , Flavonoides/farmacologia , Células HEK293 , Humanos , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Casca de Planta/química , Extratos Vegetais/química , Plasmodium falciparum/efeitos dos fármacos
13.
Magn Reson Chem ; 52(8): 448-52, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24915750

RESUMO

Restricted rotation about the N-S partial double bonds in a bis-N-triflyl substituted 3,8-diazabicyclo[3.2.1]octane derivative 1 has been frozen at low temperature (ΔG(≠) = 11.6 kcal mol(-1)), and the existence of all four rotamers about the two N-S bonds, 3-in,8-in, 3-in,8-out, 3-out,8-in, and 3-out,8-out, respectively, proved experimentally by NMR spectroscopy and theoretically by DFT and MP2 calculations.

14.
Nat Prod Res ; 37(13): 2161-2171, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35139708

RESUMO

The CH2Cl2/MeOH (1:1) extract of Zanthoxylum holstzianum stem bark showed good antiplasmodial activity (IC50 2.5 ± 0.3 and 2.6 ± 0.3 µg/mL against the W2 and D6 strains of Plasmodium falciparum, respectively). From the extract five benzophenanthridine alkaloids [8-acetonyldihydrochelerythrine (1), nitidine (2), dihydrochelerythine (3), norchelerythrine (5), arnottianamide (8)]; a 2-quinolone alkaloid [N-methylflindersine (4)]; a lignan [4,4'-dihydroxy-3,3'-dimethoxylignan-9,9'-diyl diacetate (7)] and a dimer of a benzophenanthridine and 2-quinoline [holstzianoquinoline (6)] were isolated. The CH2Cl2/MeOH (1:1) extract of the root bark afforded 1, 3-6, 8, chelerythridimerine (9) and 9-demethyloxychelerythrine (10). Holstzianoquinoline (6) is new, and is the second dimer linked by a C-C bond of a benzophenanthridine and a 2-quinoline reported thus far. The compounds were identified based on spectroscopic evidence. Amongst five compounds (1-5) tested against two strains of P. falciparum, nitidine (IC50 0.11 ± 0.01 µg/mL against W2 and D6 strains) and norchelerythrine (IC50 value of 0.15 ± 0.01 µg/mL against D6 strain) were the most active.


Assuntos
Alcaloides , Antimaláricos , Quinolinas , Zanthoxylum , Benzofenantridinas/farmacologia , Zanthoxylum/química , Antimaláricos/química , Alcaloides/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Plasmodium falciparum , Quinolinas/farmacologia
15.
Nat Prod Res ; 37(14): 2466-2471, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35707900

RESUMO

Furofuran lignanes show important biological activities for the treatment of infectious diseases, inflammatory and metabolic pathologies. They have been isolated from leaves and barks of many plants. In Chile the native conifer Araucaria araucana produces eudesmin, matairesinol, secoisolariciresinol and lariciresinol in stemwood, branchwood and knotwood. These compounds were previously isolated by laborious flash chromatography on silica gel. Here we report the easy isolation of eudesmin by soxhlet extraction from milled knots of Araucaria araucana with hexane, followed by cryo-crystallization at -20 °C. Upon bromination of the isolated eudesmin epimerization at one benzylic position occurs, giving epieudesmin and the corresponding mono and di-brominated derivatives. The structures were determined by 1D, 2D NMR and X-ray diffraction. The analysis of products against Candida yeast showed that eudesmin has a moderate activity against different strains of Candida from 62.5 to 500 µg/mL. This activity decreases for epieudesmin, while bromine derivatives are not active.


Assuntos
Araucaria araucana , Bromo , Candida , Halogenação
16.
Org Lett ; 24(29): 5376-5380, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35848228

RESUMO

We present a divergent strategy for the fluorination of phenylacetic acid derivatives that is induced by a charge-transfer complex between Selectfluor and 4-(dimethylamino)pyridine. A comprehensive investigation of the conditions revealed a critical role of the solvent on the reaction outcome. In the presence of water, decarboxylative fluorination through a single-electron oxidation is dominant. Non-aqueous conditions result in the clean formation of α-fluoro-α-arylcarboxylic acids.

17.
Nat Prod Res ; 36(11): 2821-2829, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34044677

RESUMO

Two new arabinofuranosidetridecanol, namely 1,2-tridecanediol-1-O-α-L-5'-acetylarabinofuranoside (1) and 1,2-tridecanediol-1-O-α-L-arabinofuranoside (2) together with known compound, 1,2-tridecanediol (3) were isolated from Commiphora merkeri exudate. Compound 1 showed larvicidal activity against Ae. aegypti (LC50 = 40.66 µg/mL), An. gambiae (LC50 = 22.86 µg/mL) and Cx. quinquefasciatus (LC50 = 15.88 µg/mL). Also, Compound 2 had larvicidal activity against Ae. aegypti (LC50 = 33.79 µg/mL), An. gambiae (LC50 = 31.99 µg/mL) and Cx. quinquefasciatus (LC50 = 17.70 µg/mL). There were no significant difference of larvae mortalities (≥ 95%) among the two compounds and among mosquito species except for compound 2 at 72 h for Cx. quinquefasciatus and An. gambiae. Compound 3 was not larvicidal active even after 72 h of exposure time. In addition, none of the compound was cytotoxic to brine shrimps. The two Arabinofuranosidetridecanol are potential against mosquito species and they could be safe in the environment.


Assuntos
Aedes , Culex , Inseticidas , Animais , Commiphora , Exsudatos e Transudatos , Inseticidas/farmacologia , Larva , Extratos Vegetais
18.
Nat Prod Res ; 36(12): 3203-3206, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34293972

RESUMO

Purification of the aerial parts of Vernonia auriculifera Hiern afforded steroids (1-2), flavonoids (3-5), and polyalcohol (6). Their structures were determined using spectral evidences as well as by comparison with reported data. Iodonitrotetrazolium chloride (INT) colorimetric assay was used to assess the antibacterial activity of the extract and isolates against 13 pathogenic strains. The crude extract showed strong antibacterial activity (MIC < 100 µg/mL) against the tested bacterial strains. When combined with an efflux pump inhibitor phenylalanine beta naphthylamide (PAßN), the inhibition potency of the extract was substantially enhanced with the lowest MIC value at 4 µg/mL. Compounds 5 and 6 showed moderate activity (MIC < 100 µg/mL) against 12/13 (92.3%), and 8/13 (61.5%) bacterial strains, respectively. A minimal bactericidal concentration (MBC)/minimal inhibitory concentration (MIC) ratio ≤ 4 indicated their bactericidal effect against Escherichia coli, Enterbacter aerogenes, Klebsiella pneumoniae, Providencia stuartii, Pseudomonas aeruginosa, and Staphylococcus aureus.


Assuntos
Antibacterianos , Extratos Vegetais , Vernonia , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Testes de Sensibilidade Microbiana , Fenótipo , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Vernonia/química
19.
J Ethnopharmacol ; 296: 115501, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-35752260

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Although the available medicines can cure almost all tuberculosis drug-susceptible patients some problems including the emergence of multi-drug resistant and extensively drug-resistant strains press for the need of new anti-TB medicines. Morella salicifolia is a common plant that is widely used in traditional medicine for managing HIV and AIDS-related conditions including tuberculosis but no studies have been done to evaluate its safety and efficacy. AIM OF THE STUDY: This study was designed to investigate the antimycobacterial activity and safety of M. salicifolia extract and its constituents. MATERIAL AND METHODS: Antimycobacterial activity of the crude extract was tested against non-pathogenic mycobacteria including Mycobacterium aurum (MA), Mycobacterium indicus pranii (MIP) and Mycobacterium madagascariense (MM) using the broth microdilution method. Bioassay-guided fractionation was employed to isolate the active compounds. Some of the isolated active compounds were tested for antimycobacterial activity against the standard and selected clinical isolates of M. tuberculosis. Safety of the crude extract was assessed using cytotoxicity assay and oral acute toxicity testing. RESULTS: The crude extract exhibited antimycobacterial activity against all the species used. The study led to isolation of six compounds; four pentacyclic triterpenoids; (3ß)-3-Hydroxyolean-12-en-28-oic acid (Oleanolic acid) (1), (2α,3ß)-2,3-Dihydroxyolean-12-en-28-oic acid (maslinic acid) (2), D-Friedoolean-14-ene-3ß,28-diol (taraxerol) (3), and D-Friedoolean-14-en-3ß-ol (myricadiol) (4), and two diarylheptanoids; (±)-myricanol (5) and myricanone (6). The six compounds exhibited activity against three nonpathogenic mycobacteria species. Compound 2, was the most active, with MICs of 17, 28 and 56 µg/ml against MM, standard a M. tuberculosis strain H37RV and rifampicin resistant M. tuberculosis clinical isolates, respectively. The crude extract did not show toxicity on peripheral blood mononuclear cells and it was safe in mice following acute oral toxicity test. CONCLUSION: The results from this study indicate that some isolated compounds in Morella salicifolia could form potential scaffolds for drug development efforts targeting M. tuberculosis. More studies are needed to further explore the potential of the plant extract and its secondary metabolites in the management of HIV and AIDS-related conditions using in-vivo models.


Assuntos
Infecções por HIV , Mycobacterium tuberculosis , Myricaceae , Tuberculose , Animais , Antituberculosos/farmacologia , Bioensaio , Leucócitos Mononucleares , Camundongos , Testes de Sensibilidade Microbiana , Extratos Vegetais/toxicidade , Tuberculose/tratamento farmacológico
20.
Nat Prod Res ; 36(11): 2758-2766, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34000936

RESUMO

Extracts from Securidaca longipedunculata showed antiplasmodial activities against reference clones and clinical isolates using SYBR Green I method. A new benzophenone, 2,3,4,5-tetramethoxybenzophenone (1) was isolated and characterized along with seven known compounds: 4-hydroxy-2,3-dimethoxybenzophenone (2); 3-hydroxy-5-methoxybiphenyl (3), methyl-2-hydroxy-6-methoxybenzoate (4), benzyl-2-hydroxy-6-methoxybenzoate (5), 2-hydroxy-6-methoxybenzoic acid (6), 2,4,5-trimethoxybenzophenone (7) and 2-methoxy-3,4-methylenedioxybenzophenone (8). Compounds 1 and 2 showed ex vivo antiplasmodial activities (IC50 28.8 µM and 18.6 µM, respectively); while 5 and 8 showed in vivo activities (IC50 19.7 µM and 14.5 µM, respectively) against D6 strain. In a cytotoxicity assay, all the extracts (with an exception of the MeOH extract of the leaves) and pure compounds were not toxic to the normal LO2 and BEAS cell-lines, while the methanol roots extract (IC50 66.4 µg/mL against A549, and 77.4 µg/mL against HepG2), compounds 6 (IC50 22.2 µM against A549) and 7 (IC50 45.2 µM against HepG2) were weakly active against cancerous cell-lines.


Assuntos
Antimaláricos , Polygalaceae , Securidaca , Antimaláricos/farmacologia , Benzofenonas/farmacologia , Éteres de Hidroxibenzoatos , Extratos Vegetais/farmacologia , Plasmodium falciparum
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