RESUMEN

We have synthesized twenty-three 1,4-dihydropyridine derivatives (1,4-DHPs) by using a microwave-assisted one-pot multicomponent Hantzsch reaction and evaluated their antibacterial activity against a representative panel of cariogenic bacteria and their in vitro antileishmanial activity against Leishmania (L.) amazonensis promastigotes and amastigotes. Thirteen compounds were moderately active against Streptococcus sanguinis, Streptococcus mitis, and Lactobacillus paracasei. Compound 22 (diethyl 4-(3-methoxy-4-hydroxyphenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate) displayed moderate antibacterial activity against S. mitis and S. sanguinis, with a Minimum Inhibitory Concentration (MIC) of 500 µg/mL); compounds 8 (ethyl 2,7,7-trimethyl-4-(3-chlorophenyl)-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3-carboxylate) and 10 (ethyl 2,7,7-trimethyl-4-(3-nitrophenyl)-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3-carboxylate) were moderately active against S. sanguinis (MIC=500 µg/mL) and very active against L. amazonensis promastigotes (IC50=43.08 and 34.29 µM, respectively). Among the eight 1,4-DHPs that were active (IC50 <50 µM) against L. amazonensis promastigotes, compound 13 (ethyl 2,7,7-trimethyl-4-(3,4,5-trimethoxyphenyl)-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3-carboxylate) was the most active (IC50=24.62 µM) and had a Selectivity Index (SI) higher than 4 compared to GM07492 A cells. On the other hand, compounds 7 (ethyl 2,7,7-trimethyl-4-(3-fluorophenyl)-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3-carboxylate) and 9 (ethyl 2,7,7-trimethyl-4-(2-nitrophenyl)-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3-carboxylate) were the most active against L. amazonensis amastigotes (IC50=12.53 and 13.67 µM, respectively; SI>7.9 and >7.3, respectively) after 24 h of treatment. Our results indicated that asymmetric 1,4-DHPs derived from dimedone exhibit antileishmanial potential.

RESUMEN

Artepillin C, drupanin, and plicatin B are prenylated phenylpropanoids that naturally occur in Brazilian green propolis. In this study, these compounds and eleven of their derivatives were synthesized and evaluated for their in vitro antimicrobial activity against a representative panel of oral bacteria in terms of their minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values. Plicatin B (2) and its hydrogenated derivative 8 (2',3',7,8-tetrahydro-plicatin B) were the most active compounds. Plicatin B (2) displayed strong activity against all the bacteria tested, with an MIC of 31.2 µg/mL against Streptococcus mutans, S. sanguinis, and S. mitis. On the other hand, compound 8 displayed strong activity against S. mutans, S. salivarius, S. sobrinus, Lactobacillus paracasei (MIC = 62.5 µg/mL), and S. mitis (MIC = 31.2 µg/mL), as well as moderate activity against Enterococcus faecalis and S. sanguinis (MIC = 125 µg/mL). Compounds 2 and 8 displayed bactericidal effects (MBC: MIC ≤ 4) against all the tested bacteria. In silico studies showed that the complexes formed by compounds 2 and 8 with the S. mitis, S. sanguinis, and S. mutans targets (3LE0, 4N82, and 3AIC, respectively) had energy score values similar to those of the native S. mitis, S. sanguinis, and S. mutans ligands due to the formation of strong hydrogen bonds. Moreover, all the estimated physicochemical parameters satisfied the drug-likeness criteria without violating the Lipinski, Veber, and Egan rules, so these compounds are not expected to cause problems with oral bioavailability and pharmacokinetics. Compounds 2 and 8 also had suitable ADMET parameters, as the online server pkCSM calculates. These results make compounds 2 and 8 good candidates as antibacterial agents against oral bacteria.

RESUMEN

Callistemon viminalis has been widely known due to its therapeutic properties. Tuberculosis is a deadly infectious disease caused predominantly by Mycobacterium tuberculosis. Other respiratory diseases may also be caused by nontuberculous mycobacteria. Malassezia furfur causes dermal inflammation and tissue damage. This study aimed to evaluate in vitro inhibitory effects of essential oils (EOs) from C. viminalis leaves (EO-CL) and flowers (EO-CF) against M. tuberculosis, Mycobacterium kansasii, Mycobacterium avium and M. furfur strains. Their cytotoxic activity was evaluated by the brine shrimp assay. Resulting MIC values of all EOs under study were promising since they ranged from 50 to 100 µg/mL. Both EO-CL and EO-CF showed nontoxicity against Artemia salina by the brine shrimp assay (LC50 > 1000 µg/mL). GC-FID and GC-MS analyses showed that 1,8-cineole was the major component of both EOs. These results revealed the promising potential of EO-CL and EO-CF to develop new antibacterial and antifungal drugs.

RESUMEN

The study aimed to assess the chemical composition of Miconia ibaguensis leaves extracts and fractions obtained from the ethanolic extract (EE), along with evaluating their antifungal, antibacterial, antidiabetic, and antioxidant activities. The ethyl acetate fraction (EAF) exhibited potent antifungal activity against Candida spp (1.95-3.90 µg mL-1) and potent antioxidant activity in the DPPH (1.74±0.07 µg mL-1), FRAP (654.01±42.09 µmol ETrolox/gsample), and ORAC (3698.88±37.28 µmol ETrolox/gsample) methods. The EE displayed inhibition against the α-amylase enzyme (8.42±0.05 µg mL-1). Flavonoids, hydrolysable tannins, triterpenoids, and phenolic acids, identified in the EE and fractions via (-)-HPLC-ESI-MS/MS analysis, were found to contribute to the species' biological activity potentially. These findings suggest promising avenues for further research and potential applications in pharmacology and natural products, offering new possibilities in the fight against global health issues.

Asunto(s)

Antibacterianos , Antifúngicos , Antioxidantes , Hipoglucemiantes , Melastomataceae , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Hojas de la Planta , Hojas de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Extractos Vegetales/aislamiento & purificación , Melastomataceae/química , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antifúngicos/farmacología , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Hipoglucemiantes/farmacología , Hipoglucemiantes/química , Hipoglucemiantes/aislamiento & purificación , Candida/efectos de los fármacos , alfa-Amilasas/antagonistas & inhibidores , alfa-Amilasas/metabolismo , Flavonoides/química , Flavonoides/farmacología , Flavonoides/aislamiento & purificación , Cromatografía Líquida de Alta Presión

RESUMEN

Pterodon pubescens Benth is a Brazilian medicinal plant (sucupira, in Brazilian Portuguese). This paper aims to determine the volatile composition and antibacterial activities of hexane extract from P. pubescens seeds (HE-PP). Antibacterial activities were screened by the microdilution broth method in 96-well culture plates and MIC values were expressed as µg/mL. HE-PP was active against several oral bacteria whose MIC values ranged between 12.5 µg/mL and 50 µg/mL and against three mycobacterial strains (MIC = 125 µg/mL and 500 µg/mL). In addition, HE-PP was active against Xanthomonas citri strain (MIC = 100 µg/mL). Cytotoxic activity of the extract was evaluated in human tumour and non-tumour cell lines. HE-PP showed selective cytotoxicity to cervical adenocarcinoma (HeLa cells - IC50 = 53.47 µg/mL). Its major constituents were identified by GC-MS and GC-FID: E-caryophyllene, vouacapane, E-geranylgeraniol and dehydroabietol. Results reinforce the biological potential of HE-PP against a broad spectrum of pathogenic and phytopathogenic bacteria.

RESUMEN

Citrus canker, which is caused by Xanthomonas citri, is a severe disease that affects citrus plants worldwide. This paper aimed to compare, for the first time, the chemical composition and anti-Xanthomonas citri activities of essential oils from Schinus molle fresh and dry leaves (EO-FL and EO-DL, respectively). Anti-X. citri activity of spathulenol, the major constituent of oils, was also evaluated. Activities were screened by the broth microdilution method on 96-well culture plates. Three major constituents were identified in EO-FL and EO-DL by GC-MS and GC-FID: spathulenol, ß-caryophyllene and caryophyllene oxide. EO-DL (MIC = 31.25 µg/mL), EO-FL (MIC = 62.5 µg/mL) and spathulenol (MIC = 100 µg/mL) were active against X. citri strains (resistant, tolerant and sensitive to copper). Even though results showed that in vitro potential of EO-FL, EO-DL and spathulenol against X. citri, further in vivo studies are needed to prove their applicability to the biocontrol of citrus canker.

RESUMEN

In the present work, the synthesis, characterization, antifungal activity, molecular docking study and in silico approach of five thiosemicarbazone derivatives and their corresponding zinc(II) complexes are described. The compounds were characterized by elemental analysis, IR, UV-Vis and NMR spectroscopic measurements, molar conductivity measurements, emission spectra, high-resolution mass spectrometry and X ray study. The antifungal activity of the free ligands and synthesized compounds was preliminarily evaluated against Candida albicans (ATCC 90028), Candida tropicalis (ATCC 13803) and Candida glabrata (ATCC 2001), by the minimum inhibitory concentration (MIC) assay. Two complexes, 4 (MIC = 3.18 to 6.37 µM) and 5 (MIC = 25.95 µM for all) showed promising results, being highly active against all strains evaluated. The X-ray analyses shown that the complex 2 crystallizes in the centrosymmetric space group P21/c of the monoclinic system and the coordination sphere around zinc(II) atom is better described as slightly distorted octahedral. The Hirshfeld surface (HS) analysis showed that non-classical H···H and C···H/H···C contacts contribute with 65.9% while the S···H and N···H (21%) and Cl···H and O···H interactions (12%) complete the HS area. The molecular docking results, performed against CYP51 enzyme (sterol 14α-demethylase) of C. albicans and C. glabrata shows that the complexes 4 (ΔG = -10.75 and - 12.90 kcal/ mol) and 5 (ΔG = -11.12 and - 14.53 kcal/ mol) showed the highest binding free energies of all compounds. The ADME-Tox (absorption, distribution, metabolism, excretion and toxicity) in silico parameters evaluated showed promising results for all compounds.

Asunto(s)

Complejos de Coordinación , Tiosemicarbazonas , Simulación del Acoplamiento Molecular , Antifúngicos/química , Zinc/química , Ligandos , Tiosemicarbazonas/química , Pruebas de Sensibilidad Microbiana , Candida albicans , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Estructura Molecular

RESUMEN

This study aimed to investigate the chemical composition as well as the antibacterial, antiparasitic, and cytotoxic potentialities of the Brazilian Chrysopogon zizanioides root essential oil (CZ-EO) In addition, CZ-EO cytotoxicity to LLCMK2 adherent epithelial cells was assessed. The major compounds identified in CZ-EO were khusimol (30.0 ± 0.3%), ß-eudesmol (10.8 ± 0.3%), α-muurolene (6.0 ± 0.1%), and patchouli alcohol (5.6 ± 0.2%). CZ-EO displayed optimal antibacterial activity against Prevotella nigrescens, Fusobacterium nucleatum, Prevotella melaninogenica, and Aggregatibacter actinomycetemcomitans, with Minimum Inhibitory Concentration (MIC) values between 22 and 62.5 µg/mL and Minimum Bactericidal Concentration (MBC) values between 22 and 400 µg/mL. CZ-EO was highly active against the L. amazonensis promastigote and amastigote forms (IC50 = 7.20 and 16.21 µg/mL, respectively) and the T. cruzi trypomastigote form (IC50 = 11.2 µg/mL). Moreover, CZ-EO showed moderate cytotoxicity to LLCMK2 cells, with CC50 = 565.4 µg/mL. These results revealed an interesting in vitro selectivity of CZ-EO toward the L. amazonensis promastigote and amastigote forms (Selectivity Index, SI = 78.5 and 34.8, respectively) and the T. cruzi trypomastigote form (SI = 50.5) compared to LLCMK2 cells. These results showed the promising potential of CZ-EO for developing new antimicrobial, antileishmanial, and antitrypanosomal drugs.

RESUMEN

The current trend toward using natural food additives, cosmetics, and medicines has motivated industries to substitute synthetic compounds for natural products. Essential oils (EOs) from medicinal plants are a well-known source of chemical compounds that display several interesting biological activities, including antimicrobial action. In this study, we investigated the antibacterial activity of EOs extracted from three Piperaceae species collected in the Brazilian Amazon region against a representative panel of cariogenic bacteria. The minimum inhibitory concentration (MIC) of the essential oils extracted from Peperomia pellucida (PP-EO), Piper marginatum (PM-EO), and Piper callosum (PC-EO) was determined against Streptococcus mutans, S. mitis, S. sanguinis, S. salivarius, S. sobrinus, Enterococcus faecalis, and Lactobacillus casei by using the microplate microdilution method. PM-EO, PC-EO, and PP-EO displayed antibacterial activity against all the tested cariogenic bacteria. PM-EO displayed the best inhibitory activity, with MIC values ranging from 50 to 500 µg/mL. The lowest MIC values were obtained for PM-EO against S. mitis (MIC = 75 µg/mL), Lactobacillus casei (MIC = 50 µg/mL), and S. mutans (MIC = 50 µg/mL). Gas chromatography mass spectrometry (GC-MS) analysis allowed the chemical composition of all the EOs to be identified. The main constituents of PM-EO, PC-EO, and PP-EO were 3,4-(methylenedioxy)propiophenone, α-pinene, and dillapiole, respectively. Finally, the compounds that were exclusively detected in PM-EO are highlighted. Our results suggest that PM-EO may be used in products for treating dental caries and periodontal diseases.

RESUMEN

This updated review article covers the literature between 2011 and 2021 on the antibacterial activity of EOs against the main bacteria that cause caries and periodontal diseases. The criteria to classify the in vitro antibacterial activity of EOs is updated and the most promising results are addressed.

Asunto(s)

Aceites Volátiles , Antibacterianos/farmacología , Bacterias , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/farmacología

RESUMEN

Spiranthera odoratissima A. St.-Hil. (Rutaceae) has been popularly used against abdominal pain and rheumatism. This study aimed at extracting hexane from S. odoratissima (HE-SO) leaves to identify and quantify its volatile compounds by GC-MS and GC-FID and to evaluate its antifungal, antileishmanial and antibacterial activities in vitro. HE-SO exhibited antileishmanial activity against promastigote forms of Leishmania (Leishmania) amazonensis (IC50 = 38.16 µg/mL) and was moderately active against Xylella fastidiosa (MIC = 100 µg/mL). HE-SO also showed remarkable antifungal potential against six strains of Candida species, i. e., C. albicans, C. glabrata, C. parapsilosis, C. krusei, C. tropicalis and C. orthopsilosis. The lowest MIC values were between 31.25 and 250 µg/mL. Spathulenol (20.2%), τ-cadinol (11.7%), α-cadinol (9.4%), caryophyllene oxide (9.2%) and isoaromadendrene epoxide (8.2%) were the major components identified in HE-SO. Therefore, results showed that HE-SO has promising antileishmanial and antifungal actions.

Asunto(s)

Antiprotozoarios , Leishmania mexicana , Leishmania , Aceites Volátiles , Rutaceae , Antifúngicos/química , Antiprotozoarios/farmacología , Candida , Candida glabrata , Hexanos , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/química , Hojas de la Planta/química , Xylella

RESUMEN

Origanum vulgare, known for its medicinal value, is officially accepted in many countries. The flowers and leaves are used globally in homeopathy. In Brazilian folk medicine, O. vulgare has been used to treat diabetes mellitus. This study evaluated the hypoglycemic activity of an infusion extract (RosCE) of commercially available O. vulgare leaves in alloxan-induced diabetic rats. Oral administration of RosCE resulted in the reduction of blood glucose levels after the first day of treatment, compared to the diabetic control group. These results showed that RosCE displays hypoglycemic activity, which may be due to the combined effect of rosmarinic acid, and other minor compounds. Reversed phase-high performance liquid chromatography-diode array detection was used to identify and quantify the major constituents of RosCE. This study presents evidence that supports the folkloric use of O. vulgare for the treatment of hyperglycemia, confirming the use of its infusion as an antidiabetic herbal medicine.

Asunto(s)

Diabetes Mellitus Experimental , Origanum , Aloxano , Animales , Glucemia , Cinamatos , Depsidos , Diabetes Mellitus Experimental/inducido químicamente , Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/farmacología , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Ratas , Ácido Rosmarínico

RESUMEN

Cercospora brachiata is a phytopathogenic fungus. To know more about the metabolites produced by this fungus, the objective of this work was to identify, isolate and characterize substances present in extracts of the growth broth and mycelium, using gas chromatography with mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR). It was also objective to evaluate the antibacterial activity of the extracts. Among the compounds identified, fatty acids, esters, and steroids can be highlighted. The main compounds identified are 9-hexadecenoic, hexadecenoic, oleic, octadecanoic, lauric, myristic, palmitic, doceno-13-enoic, stearic, linoleic, and nonadecanoic acids present in almost all extracts. For the antibacterial activity, the broth microdilution method was used. The ethyl acetate extract of the mycelium presented inhibitory concentrations (MICs) against the bacterium Actinomyces naeslundii (100 µg mL-1) and Streptococcus sanguinis (200 µg mL-1). Finally, two steroids were isolated and identified in the hexane extract of mycelium: ergosta-6,22-dien-3ß,5α,8α-triol and brassicasterol.

RESUMEN

Considering the promising previous results on the remarkable activity exhibited by cobalt(III) and manganese(II) thiosemicarbazone compounds as antibacterial agents, the present study aimed to prepare and then evaluate the antibacterial activity of two different types of Cu(II) complexes based on a 2-acetylpyridine-N(4)-methyl-thiosemicarbazone ligand (Hatc-Me), a monomer complex [CuCl(atc-Me)] and a novel dinuclear complex [{Cu(µ-atc-Me)}2µ-SO4]. The compounds were characterized by infrared spectra, ultraviolet visible and CHN elemental analysis. In addition, the crystalline structures of the complexes were determined by single-crystal X-ray diffraction. In both cases, the Schiff base ligand coordinated in a tridentate mode via the pyridine nitrogen, imine nitrogen and sulfur atoms. The two Cu(II) atoms in the dimer are five coordinate, consisting of three NNS-donor atoms from the thiosemicarbazone ligand connected by a sulfate bridge. The Hirshfeld surface and energy framework of the complexes were additionally analyzed to verify the intermolecular interactions. The biological activity of the Cu(II) salts, the free ligand and its Cu(II) complexes was evaluated against six strains of mycobacteria including Mycobacterium tuberculosis. The complexes showed promising results as antibacterial agents for M. avium and M. tuberculosis, which ranged from 6.12 to 12.73 µM. Furthermore, molecular docking analysis was performed and the binding energy of the docked compound [{Cu(µ-atc-Me)}2µ-SO4] with M. tuberculosis and M. avium strains were extremely favorable (-11.11 and - 14.03 kcal/mol, respectively). The in silico results show that the complexes are potential candidates for the development of new antimycobacterial drugs.

Asunto(s)

Antituberculosos/farmacología , Complejos de Coordinación/farmacología , Tiosemicarbazonas/farmacología , Antituberculosos/síntesis química , Antituberculosos/metabolismo , Antituberculosos/farmacocinética , Proteínas Bacterianas/metabolismo , Complejos de Coordinación/síntesis química , Complejos de Coordinación/metabolismo , Complejos de Coordinación/farmacocinética , Cobre/química , Ligandos , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Estructura Molecular , Mycobacterium avium/efectos de los fármacos , Mycobacterium kansasii/efectos de los fármacos , Mycobacterium tuberculosis/efectos de los fármacos , Unión Proteica , Relación Estructura-Actividad , Termodinámica , Tiosemicarbazonas/síntesis química , Tiosemicarbazonas/metabolismo , Tiosemicarbazonas/farmacocinética

RESUMEN

Brazilian green and red propolis stand out as commercial products for different medical applications. In this article, we report the antimicrobial activities of the hydroalcoholic extracts of green (EGP) and red (ERP) propolis, as well as guttiferone E plus xanthochymol (8) and oblongifolin B (9) from red propolis, against multidrug-resistant bacteria (MDRB). We undertook the minimal inhibitory (MIC) and bactericidal (MBC) concentrations, inhibition of biofilm formation (MICB50 ), catalase, coagulase, DNase, lipase, and hemolysin assays, along with molecular docking simulations. ERP was more effective by displaying MIC and MBC values <100 µg mL-1 . Compounds 8 and 9 displayed the lowest MIC values (0.98 to 31.25 µg mL-1 ) against all tested Gram-positive MDRB. They also inhibited the biofilm formation of S. aureus (ATCC 43300 and clinical isolate) and S. epidermidis (ATCC 14990 and clinical isolate), with MICB50 values between 1.56 and 6.25 µg mL-1 . The molecular docking results indicated that 8 and 9 might interact with the catalase's amino acids. Compounds 8 and 9 have great antimicrobial potential.

Asunto(s)

Antiinfecciosos/farmacología , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Própolis/química , Antiinfecciosos/química , Antiinfecciosos/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Benzofenonas/química , Benzofenonas/aislamiento & purificación , Benzofenonas/metabolismo , Benzofenonas/farmacología , Sitios de Unión , Biopelículas/efectos de los fármacos , Brasil , Catalasa/química , Catalasa/metabolismo , Dominio Catalítico , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Própolis/metabolismo , Própolis/farmacología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología

RESUMEN

Considering our previous findings on the remarkable activity exhibited by cobalt(III) with 2-acetylpyridine-N(4)-R-thiosemicarbazone (Hatc-R) compounds against Mycobacterium tuberculosis, the present study aimed to explored new structure features of the complexes of the type [Co(atc--R)2]Cl, where R = methyl (Me, 1) or phenyl (Ph, 2) (13C NMR, high-resolution mass spectrometry, LC-MS/MS, fragmentation study) together with its antibacterial and antiviral biological activities. The minimal inhibitory and minimal bactericidal concentrations (MIC and MBC) were determined, as well as the antiviral potential of the complexes on chikungunya virus (CHIKV) infection in vitro and cell viability. [Co(atc-Ph)2]Cl revealed promising MIC and MBC values which ranged from 0.39 to 0.78 µg/mL in two strains tested and presented high potential against CHIKV by reducing viral replication by up to 80%. The results showed that the biological activity is strongly influenced by the peripheral substituent groups at the N(4) position of the atc-R1- ligands. In addition, molecular docking analysis was performed. The relative binding energy of the docked compound with five bacteria strains was found in the range of -3.45 and -9.55 kcal/mol. Thus, this work highlights the good potential of cobalt(III) complexes and provide support for future studies on this molecule aiming at its antibacterial and antiviral therapeutic application.

Asunto(s)

Cobalto/farmacología , Tiosemicarbazonas/química , Antibacterianos/farmacología , Antivirales/farmacología , Bacterias/efectos de los fármacos , Fiebre Chikungunya/tratamiento farmacológico , Virus Chikungunya/efectos de los fármacos , Cromatografía Liquida/métodos , Cobalto/química , Complejos de Coordinación/farmacología , Ligandos , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Espectrometría de Masas en Tándem/métodos , Tiosemicarbazonas/farmacología

RESUMEN

Scheelea phalerata Mart. ex Spreng (Arecaceae) is a palm tree found in the Brazilian cerrado. There are no topics related to volatile oils from S. phalerata leaves in the literature. This work determines its chemical composition and evaluates the biological activity under two different seasonal conditions (dry and rainy seasons). The dry essential oil yield was 0.034 ± 0.001% and the rainy essential oil yield was 0.011 ± 0.003%. Both essential oils presented different qualitative and quantitative compositions (99.4 and 98.5%). The main constituents of the dry essential oil were phytol (36.7%), nonadecane (9.7%), linolenic acid (9.1%), (Z)-hex-3-en-1-ol (4.2%), and squalene (4.0%). The main constituents of the rainy essential oil were phytol (26.1%), palmitic acid (18.7%), hexan-1-ol (15.6%), (Z)-hex-3-en-1-ol (9.7%), and oleic acid (4.0%). The antileishmanial activity against promastigotes of Leishmania amazonensis was observed only for the rainy season essential oil (IC50 value of 165.05 ± 33.26 µg mL-1). A molecular docking study showed that alcohols exert a paramount efficacy and that the action of some essential oil compounds may be similar to that of amphotericin B. Still, only the essential oil from the dry season showed moderate antibacterial activity against S. sanguinis (MICs 200-400 µg mL-1). The cytotoxicity against Vero cells was identical (>512) for both essential oils. The novel data here for both chemical characterization and biological activity, in particular, evidence that the action of these compounds is similar to that of amphotericin B, provide valuable information to the drug-discovery field.

RESUMEN

A new method of screening was developed to generate 770 organic and water-soluble fractions from extracts of nine species of marine sponges, from the growth media of 18 species of marine-derived fungi, and from the growth media of 13 species of endophytic fungi. The screening results indicated that water-soluble fractions displayed significant bioactivity in cytotoxic, antibiotic, anti-Leishmania, anti-Trypanosoma cruzi, and inhibition of proteasome assays. Purification of water-soluble fractions from the growth medium of Penicillium solitum IS1-A provided the new glutamic acid derivatives solitumine A (1), solitumine B (2), and solitumidines A-D (3-6). The structures of compounds 1-6 have been established by analysis of spectroscopic data, chemical derivatizations, and vibrational circular dichroism calculations. Although no biological activity could be observed for compounds 1-6, the new structures reported for 1-6 indicate that the investigation of water-soluble natural products represents a relevant strategy in finding new secondary metabolites.

Asunto(s)

Glutamatos/química , Regiones Antárticas , Hongos/química , Estructura Molecular , Penicillium/química , Agua

RESUMEN

In Brazilian folk medicine, Protium heptaphyllum is used to treat inflammatory conditions and to hasten wound repair. This paper aims to investigate the chemical composition and the in vitro antibacterial effects of the essential oils (EOs) obtained from P. heptaphyllum leaves and ripe and unripe fruits against a representative panel of oral pathogens. The GC-FID and GC-MS analysis revealed that the major components determined in P. heptaphyllum essential oils were myrcene (59.0%), ß-elemene (17.2%), limonene (12.9%), spathulenol (12.6%), α-cubebene (11.6%), germacrene D (10.6%), trans-nerolidol (9.8%), and α-cadinol (8.8%). The essential oils of the ripe and unripe fruits showed the strongest antibacterial activity against the anaerobic bacteria Prevotella nigrescens (MIC = 50 µg/mL). The leaf essential oil displayed very promising activity against Streptococcus mutans (MIC = 50 µg/mL) and Streptococcus mitis (MIC = 62.5 µg/mL). The antibacterial activity of EOs against oral pathogens is also described for the first time. [Formula: see text].

Asunto(s)

Antibacterianos/aislamiento & purificación , Burseraceae/química , Aceites Volátiles/química , Monoterpenos Acíclicos/análisis , Alquenos/análisis , Antibacterianos/química , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Sesquiterpenos/análisis , Sesquiterpenos de Germacrano/análisis , Streptococcus mutans/efectos de los fármacos , Terpenos/análisis