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1.
An Acad Bras Cienc ; 91(3): e20180404, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365649

RESUMO

In this study, the antimicrobial, antioxidant and antitumor activity of ethanol extracts obtained from Phlomis russeliana (Sims.) Lag. ex Benth. (Lamiaceae) were evaluated. Disc diffusion and microdilution methods were used to test the extracts for antimicrobial activity against seven bacteria strains (Bacillus cereus ATCC 7064, Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 6538P, Escherichia coli ATCC 10538, Proteus vulgaris ATCC 6899, Salmonella typhimurium CCM 5445 and Pseudomonas aeruginosa ATCC 27853) and four yeast strains (Kluyveromyces fragilis ATCC 8608, Rhodotorula rubra ATCC 70403, Debaryomyces hansenii DSM 70238 and Candida albicans ATCC 10239). Notably, they were more effective against the yeast strains than the bacterial strains. Of the yeast cultures, D. hanseii was among the most susceptible, having an inhibition zone of 16.2 mm with minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of 64(128)µg/ml, respectively. For cytotoxic determination, Caco-2 cells were cultured as per ATCC protocol, and were treated with log concentrations (5-80 mg/ml) of P. russeliana. The potency of cell growth inhibition for each extract was expressed as an IC50 value. Moreover, oxidant capacity was evaluated via TOC assay. This product induced antiproliferative activity of 31.33% at 40 mg/ml and 20.96% at 80 mg/ml, without toxic effects on cells, although the oxidant capacity was decreased to 27.06 ± 0.7 nm in the 80 mg/ml-applied group compared to 47.9 ± 1.8 nm in the untreated one. Advanced pharmacological studies are needed to further evaluate P. russeliana for distinctive features.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Candida albicans/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Phlomis/química , Extratos Vegetais/farmacologia , Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Células CACO-2 , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Bactérias Gram-Negativas/classificação , Bactérias Gram-Positivas/classificação , Humanos , Turquia
2.
Medicina (B Aires) ; 79(3): 167-173, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-31284250

RESUMO

Diabetic foot infections are related to severe complications and constitute the main reason for diabetes-related hospitalization and lower limb amputations. A diabetic foot infection requires prompt actions to avoid progression of the infected wound; a soft tissue sample has to be taken for microbiological culture and empiric antibiotic therapy must be started immediately. Empiric antibiotic schemes should be chosen based on the severity of the infection and the local prevalence of microbial causal agents. Therefore, it is important to monitor these indicators. The aim of this study was to determine which microorganisms were more prevalent in cultures of diabetic foot infections during 2018 and what antibiotic combination was better to cover local microbiology, compared with data available from 2015 for a similar cohort. A total of 68 positive cultures were obtained of 72 soft tissue specimens analyzed. The most frequent microorganisms were Gram negative (47.1%), and resulted significantly more frequent than in 2015 (24.6%) p = 0.01. These Gram negative germs also resulted more sensitive to ciprofloxacin than in 2015 (62.5% vs. 25.0%) p = 0.03. Amoxicillin-clavulanate plus ciprofloxacin was the optimal combination therapy in 2018, while in 2015 it was amoxicillin-clavulanate plus trimethoprim sulfamethoxazole. In agreement with these results, we recommend amoxicillin-clavulanate plus ciprofloxacin as the empiric antibiotic regimen of choice for soft tissue infections in diabetic foot. We consider surveillance of local microbiology to be an important tool in the management of diabetic foot infections.


Assuntos
Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Antibacterianos/uso terapêutico , Ciprofloxacino/uso terapêutico , Pé Diabético/tratamento farmacológico , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Pé Diabético/etiologia , Pé Diabético/microbiologia , Quimioterapia Combinada , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia
3.
J Photochem Photobiol B ; 197: 111541, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31272033

RESUMO

Here, we report the novel fabrication of ZnO nanoparticles using the Costus igneus leaf extract. Gas chromatography-mass spectrometry (GC-MS) and proton nuclear magnetic resonance (1H NMR) spectroscopy to determine the bioactive components present in the plant extract. The synthesis of Ci-ZnO NPs (C. igneus- coated zinc oxide nanoparticles) was accomplished using a cost-effective and simple technique. Ci-ZnO NPs were specified using UV-visible spectroscopy, FTIR, XRD, and TEM. Ci-ZnO NPs was authenticated by UV-Vis and exhibited a peak at 365 nm. The XRD spectra proved the crystalline character of the Ci-ZnO NPs synthesized as hexagonal wurtzite. The FTIR spectrum illustrated the presence of possible functional groups present in Ci-ZnO NPs. The TEM micrograph showed evidence of the presence of a hexagonal organization with a size of 26.55 nm typical of Ci-ZnO NPs. The α-amylase and α-glucosidase inhibition assays demonstrated antidiabetic activity of Ci-ZnO NPs (74 % and 82 %, respectively), and the DPPH [2,2-diphenyl-1-picrylhydrazyl hydrate] assay demonstrated the antioxidant activity of the nanoparticles (75%) at a concentration of 100 µg/ml. The Ci-ZnO NPs exhibited promising antibacterial and biofilm inhibition activity against the pathogenic bacteria Streptococcus mutans, Lysinibacillus fusiformis, Proteus vulgaris, and Vibrio parahaemolyticus. Additionally, the Ci-ZnO NPs showed biocompatibility with mammalian RBCs with minimum hemolytic activity (0.633 % ±â€¯0.005 %) at a concentration of 200 µg/ml.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/química , Biofilmes/efeitos dos fármacos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Óxido de Zinco/química , Antibacterianos/síntese química , Antibacterianos/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Costus/química , Costus/metabolismo , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/fisiologia , Química Verde , Hemólise/efeitos dos fármacos , Humanos , Insulina/química , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
4.
J Photochem Photobiol B ; 197: 111548, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31288120

RESUMO

The visible light combined with photosensitizers (PSs) is exploited in both antitumoral and antimicrobial fields inducing a photo-oxidative stress within the target cells. Among the different PSs, porphyrins belong to the family of the most promising compounds to be used in clinical photodynamic applications. Although in the last years many porphyrins have been synthesised and tested, only a few reports concern the in vitro effects of the 5,15-diarylporphyrins. In this work, the activity of four 5,15-diarylporphyrins (compounds 7-10), bearing alkoxy-linked pyridinium appendixes, have been tested on cancer cell lines and against bacterial cultures. Among the synthetized PSs, compounds 7 and 9 are not symmetrically substituted porphyrins showing one cationic charge tethered at the end of one 4C or 8C carbon chains, respectively. On the other hand, compounds 8 and 10 are symmetrically substituted and show two chains of C4 and C8 carbons featuring a cationic charge at the end of both chains. The dicationic 8 and 10 were more hydrophilic than monocationic 7 and 9, outlining that the presence of two pyridinium salts have a higher impact on the solubility in the aqueous phase than the lipophilic effect exerted by the length of the alkyl chains. Furthermore, these four PSs showed a similar rate of photobleaching, irrespective of the length and number of chains and the number of positive charges. Among the eukaryotic cell lines, the SKOV3 cells were particularly sensitive to the photodynamic activity of all the tested diarylporphyrins, while the HCT116 cells were found more sensitive to PSs bearing C4 chain (7 and 8), regardless the number of cationic charges. The photo-induced killing effect of these porphyrins was also tested against two different bacterial cultures. As expected, the Gram positive Bacillus subtilis was more sensitive than the Gram negative Escherichia coli, and the dicationic porphyrin 8, bearing two C4 chains, was the most efficient on both microorganisms. In conclusion, the new compound 8 seems to be an optimal candidate to deepen as versatile anticancer and antibacterial photosensitizer.


Assuntos
Antibacterianos/química , Antineoplásicos/química , Fármacos Fotossensibilizantes/química , Porfirinas/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Cátions/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Luz , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/síntese química , Porfirinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo
5.
J Photochem Photobiol B ; 197: 111556, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31326842

RESUMO

Facile green synthesis of copper nanoparticles from different biological procedures has been indicated, but among all, biosynthesis of copper nanoparticles from medicinal plants is considered as the most suitable method. The use of medicinal plant material increases the therapeutical effects of copper nanoparticles. The aim of this study was green synthesis of copper nanoparticles from aqueous extract of Falcaria vulgaris leaf (CuNPs) and assessment of their cytotoxicity, antioxidant, antifungal, antibacterial, and cutaneous wound healing properties. These nanoparticles were characterized by X-ray diffraction (XRD), fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV), transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM) analysis. The synthesized CuNPs had great cell viability dose-dependently (Investigating the effect of the CuNPs on human umbilical vein endothelial cell (HUVEC) line) and indicated this method was nontoxic. Also, 2,2-diphenyl-1-picrylhydrazyl (DPPH) test was done to assess the antioxidant activities, which indicated similar antioxidant potentials for CuNPs and butylated hydroxytoluene. In part of cutaneous wound healing property of CuNPs, after creating the cutaneous wound, the rats were randomly divided into six groups: treatment with 0.2% CuNPs ointment, treatment with 0.2% CuSO4 ointment, treatment with 0.2% F. vulgaris ointment, treatment with 3% tetracycline ointment, treatment with Eucerin basal ointment, and untreated control. These groups were treated for 10 days. Treatment with CuNPs ointment remarkably increased (p ≤ .01) the wound contracture, vessel, hexosamine, hydroxyl proline, hexuronic acid, fibrocyte, and fibrocytes/fibroblast rate and substantially reduced (p ≤ .01) the wound area, total cells, neutrophil, and lymphocyte compared to other groups. In antibacterial and antifungal parts of this research, the concentration of CuNPs with minimum dilution and no turbidity was considered minimum inhibitory concentration (MIC). To determine minimum fungicidal concentration (MFC) and minimum bactericidal concentration (MBC), 60 µL MIC and three preceding chambers were cultured on Sabouraud Dextrose Agar and Muller Hinton Agar, respectively. The minimum concentration with no fungal and bacterial growth were considered MFC and MBC, respectively. CuNPs inhibited the growth of all fungi at 2-4 mg/mL concentrations and removed them at 4-8 mg/mL concentrations (p ≤ .01). In case of antibacterial effects of CuNPs, they inhibited the growth of all bacteria at 2-8 mg/mL concentrations and removed them at 4-16 mg/mL concentrations (p ≤ .01). The results of XRD, FT-IR, UV, TEM, and FE-SEM confirm that the aqueous extract of F. vulgaris leaf can be used to yield copper nanoparticles with notable amount of antioxidant, antifungal, antibacterial, and cutaneous wound healing potentials without any cytotoxicity. Further clinical trials are necessary for confirmation these therapeutical effects of CuNPs in human.


Assuntos
Apiaceae/química , Cobre/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Antioxidantes/química , Apiaceae/metabolismo , Candida/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Folhas de Planta/química , Folhas de Planta/metabolismo , Ratos , Pele/efeitos dos fármacos , Pele/patologia , Cicatrização/efeitos dos fármacos
6.
J Photochem Photobiol B ; 197: 111554, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31326843

RESUMO

Bovine mastitis is an endemic disease of dairy cattle that is considered to be one of the most frequent and costly diseases in veterinary medicine. An increase in the incidence of disease results in the increased use of antibiotics, which in turn increases the potential of bacterial resistance. This study aimed to investigate the effectiveness of antimicrobial photodynamic therapy (aPDT) in the treatment of bovine mastitis, as an alternative to systemic antibiotics. To identify the key factors affecting photoinactivation efficacy, realistic experiments in view of the end-use were conducted in milk samples using two different photosensitizers: methylene blue (MB) and silicon (IV) phthalocyanine derivative (SiPc). We explored the effects of divalent ions and fat content on the aPDT outcome and determined influence of different proteins on aPDT efficacy. Levels of bacterial sensitivity to PSs varied depending on the type of bacteria (Gram-positive vs. Gram-negative) and light exposure time. Critical interrelated factors affecting aPDT in milk were identified and an efficient combination of treatment conditions that can lead to a full photodynamic inactivation of bacteria was determined.


Assuntos
Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Leite/microbiologia , Fármacos Fotossensibilizantes/farmacologia , Animais , Bovinos , Feminino , Indóis/química , Indóis/farmacologia , Indóis/uso terapêutico , Luz , Mastite Bovina/tratamento farmacológico , Mastite Bovina/microbiologia , Mastite Bovina/patologia , Azul de Metileno/farmacologia , Azul de Metileno/uso terapêutico , Proteínas do Leite/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Oxigênio Singlete/metabolismo
7.
Chem Pharm Bull (Tokyo) ; 67(7): 620-631, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257316

RESUMO

Natural products are still rich sources of clinically used medicines and lead compounds for them. This review summarizes chemical studies carried out by the author on natural products of microorganism origin, many of which were discovered at the Institute of Microbial Chemistry (BIKAKEN). Caprazamycin B is a liponucleoside antibiotic from which CPZEN-45, an antituberculosis agent with a unique mode of action, was developed. Intervenolin and leucinostatin A exert antiproliferative activity toward tumor cells in the presence of the corresponding stromal cells, which implies that the primary molecular targets of these molecules should be related to growth signals from normal (stromal) cells. Details of the endeavors to establish efficient synthetic routes to these compounds which accelerated structure-activity relationship studies and further evaluation of biological activity are described.


Assuntos
Anti-Infecciosos/química , Antineoplásicos/química , Produtos Biológicos/química , Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Azepinas/química , Azepinas/farmacologia , Produtos Biológicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Peptídeos/química , Peptídeos/farmacologia , Relação Estrutura-Atividade
8.
J Nanobiotechnology ; 17(1): 84, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31291944

RESUMO

BACKGROUND: Nanoceria has recently received much attention, because of its widespread biomedical applications, including antibacterial, antioxidant and anticancer activity, drug/gene delivery systems, anti-diabetic property, and tissue engineering. MAIN BODY: Nanoceria exhibits excellent antibacterial activity against both Gram-positive and Gram-negative bacteria via the generation of reactive oxygen species (ROS). In healthy cells, it acts as an antioxidant by scavenging ROS (at physiological pH). Thus, it protects them, while in cancer cells (under low pH environment) it acts as pro-oxidant by generating ROS and kills them. Nanoceria has also been effectively used as a carrier for targeted drug and gene delivery in vitro and in vivo models. Besides, nanoceria can also act as an antidiabetic agent and confer protection towards diabetes-associated organ pathophysiology via decreasing the ROS level in diabetic subjects. Nanoceria also possesses excellent potential in the field of tissue engineering. In this review, firstly, we have discussed the different methods used for the synthesis of nanoceria as these are very important to control the size, shape and Ce3+/Ce4+ ratio of the particles upon which the physical, chemical, and biological properties depend. Secondly, we have extensively reviewed the different biomedical applications of nanoceria with probable mechanisms based on the literature reports. CONCLUSION: The outcome of this review will improve the understanding about the different synthetic procedures and biomedical applications of nanoceria, which should, in turn, lead to the design of novel clinical interventions associated with various health disorders.


Assuntos
Cério/química , Nanopartículas/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Cério/farmacologia , Sistemas de Liberação de Medicamentos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Engenharia Tecidual/métodos
9.
Chem Biodivers ; 16(8): e1900183, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31361076

RESUMO

This work describes the study of the chemical composition and bioactivity of the essential oils (EOs) of the different organs (leaves, flowers, stems and roots) from Eruca vesicaria. According to the GC and GC/MS analysis, all the EOs were dominated by erucin (4-methylthiobutyl isothiocyanate) with a percentage ranging from 17.9 % (leaves) to 98.5 % (roots). The isolated EOs were evaluated for their antioxidant (DPPH, ABTS and ß-carotene/linoleic acid), antibacterial and inhibitory property against α-amylase and α-glucosidase. Most EOs exhibited an interesting α-glucosidase and α-amylase inhibitory potential. The roots essential oil was found to be the most active with IC50 values of 0.80±0.06 and 0.11±0.01 µg mL-1 , respectively. The essential oil of roots exhibited the highest antioxidant activity (DPPH, PI=92.76±0.01 %; ABTS, PI=78.87±0.19; and ß-carotene, PI=56.1±0.01 %). The isolated oils were also tested for their antibacterial activity against two Gram-positive and three Gram-negative bacteria. Moderate results have been noted by comparison with Gentamicin used as positive control.


Assuntos
Antioxidantes/química , Brassicaceae/metabolismo , Óleos Voláteis/química , Antibacterianos/química , Antibacterianos/farmacologia , Brassicaceae/química , Flores/química , Flores/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hipoglicemiantes/química , Óleos Voláteis/metabolismo , Óleos Voláteis/farmacologia , Folhas de Planta/química , Folhas de Planta/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
10.
BMC Infect Dis ; 19(1): 585, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31277588

RESUMO

BACKGROUND: Antibiotic resistance is a worldwide problem that crosses international boundaries and spread between continents easily. Hence, information on the existence of the causative microorganisms and their susceptibility to commonly used antibiotics are essential to enhance therapeutic outcome. METHOD: A cross-sectional study was conducted retrospectively at Hawassa University Comprehensive Specialized Hospital. The culture and antibiotic sensitivity data of the isolates were collected from the record books of the microbiology unit for the study period after official permission obtained from the institutional review board. The data entered and analyzed using statistical package for social science software version 20. RESULT: A total of 693 bacteria were retrieved, of these 435(62.77%) were gram-negative and the rest 258(37.23%) were gram-positive. Most of the isolates were from a urine sample. Among gram positives isolates, S. aureus and from gram negatives Klebsiella spp are the most recurrent isolate. Almost a remarkable resistance was observed to most of the antibiotics mainly, penicillin G (81.8%) and cotrimoxazole (81.1%), for gram-positive bacteria. The gram-negative bacteria also show resistance to ampicillin (92.5%), tetracycline (85%) and cotrimoxazole (93.1%). CONCLUSIONS: Nearly all isolate show substantial rates of resistance to most of the antibiotic that is frequently used in the study area. As already known we want to emphases on the importance of performing continuous monitoring of drug susceptibility to help the empirical treatment of bacterial agents to a health professional in the region. In addition, this data might help policymakers to control of antibiotics resistance.


Assuntos
Farmacorresistência Bacteriana/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Adolescente , Adulto , Idoso , Antibacterianos/farmacologia , Criança , Pré-Escolar , Estudos Transversais , Etiópia , Feminino , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Hospitais Especializados , Hospitais Universitários , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Centros de Atenção Terciária
11.
Chem Biodivers ; 16(8): e1900131, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31173470

RESUMO

Most species of the genus Laggera are often used in traditional and folk medicines for the treatment of jaundice, inflammation, leukemia, removing phlegm, bronchitis and bacterial diseases. The essential oils obtained from Laggera plants are rich sources of oxygenated monoterpenes and sesquiterpenes. Among oxygenated monoterpenes, aromatic ether 2,5-dimethoxy-p-cymene is the most abundant and dominant compound of many essential oils of the Laggera species. Till today, to the best of our knowledge, chemical compounds of the essential oils and/or extracts of only eight Laggera species were reported from different countries. Thus, this review presents the chemical compositions and biological activities of the essential oils of these plants studied in thirteen countries. In addition, it discusses the reported ethnobotanical and ethnopharmacological information as well as biological activities of the extracts and some of the isolated compounds of Laggera plants species.


Assuntos
Asteraceae/metabolismo , Óleos Voláteis/química , Antioxidantes/química , Candida/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Medicina Tradicional , Óleos Voláteis/farmacologia , Fenóis/química , Extratos Vegetais/química , Compostos Orgânicos Voláteis/química
12.
Chem Biodivers ; 16(8): e1900145, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31207044

RESUMO

Copper oxide nanomaterials were synthesized by a facile sustainable biological method using two plant species (Zanthoxylum armatum DC. and Berberis lycium Royle). The formation of materials was confirmed by FT-IR, ATR, UV-visible, XRD, TEM, SEM, EDX, TGA and PL. The antibacterial activity was evaluated by agar well diffusion method to ascertain the efficacy of plant species extract and extract derived copper oxide nanomaterials against six Gram-positive bacteria namely Staphylococcus aureus, Streptococcus mutans, Streptococcus pyogenes, Corynebacterium diphtheriae, Corynebacterium xerosis, Bacillus cereus and four Gram-negative bacteria such as Klebsiella pneumonia, Escherichia coli, Pseudomonas aeruginosa and Proteus vulgaris against the standard drug, Ciprofloxacin for Gram-positive and Gentamicin for Gram-negative bacteria, respectively. In both cases, copper oxide nanomaterials were found to be sensitive in all the bacterial species. Sensitivity of copper oxide nanomaterials shows an be higher as compared to plant species extract against different bacteria. Scavenging activity of plant extracts along with nanomaterials have been accessed using previously reported protocols employing ascorbic acid as standard. Scavenging activity of copper oxide nanomaterials shows an increase with increase in concentration. The biological activity (bactericidal and scavenging efficiency) of plant derived copper oxide nanomaterials revealed that these materials can be used as potent antimicrobial agent and DPPH scavengers in industrial as well as pharmacological fields.


Assuntos
Antibacterianos/química , Berberis/química , Cobre/química , Depuradores de Radicais Livres/química , Nanoestruturas/química , Zanthoxylum/química , Antibacterianos/farmacologia , Berberis/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Testes de Sensibilidade Microbiana , Nanoestruturas/toxicidade , Folhas de Planta/química , Espectroscopia de Infravermelho com Transformada de Fourier , Zanthoxylum/metabolismo
13.
Eur J Med Chem ; 178: 214-231, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31185412

RESUMO

Discovery of antimicrobial agents with a novel model of action is in urgent need for the clinical management of multidrug-resistant bacterial infections. Recently, we reported the identification of a first-in-class bacterial ribosomal RNA synthesis inhibitor, which interrupted the interaction between the bacterial transcription factor NusB and NusE. In this study, a series of diaryl derivatives were rationally designed and synthesized based on the previously established pharmacophore model. Inhibitory activity against the NusB-NusE binding, circular dichroism of compound treated NusB, antimicrobial activity, cytotoxicity, hemolytic property and cell permeability using Caco-2 cells were measured. Structure-activity relationship and quantitative structure-activity relationship were also concluded and discussed. Some of the derivatives demonstrated improved antimicrobial activity than the hit compound against a panel of clinically important pathogens, lowering the minimum inhibition concentration to 1-2 µg/mL against Staphylococcus aureus, including clinical strains of methicillin-resistant Staphylococcus aureus at a level comparable to some of the marketed antibiotics. Given the improved antimicrobial activity, specific inhibition of target protein-protein interaction and promising pharmacokinetic properties without significant cytotoxicity, this series of diaryl compounds have high potentials and deserve for further studies towards a new class of antimicrobial agents in the future.


Assuntos
Compostos de Anilina/farmacologia , Antibacterianos/farmacologia , Benzilaminas/farmacologia , Ligação Proteica/efeitos dos fármacos , Bases de Schiff/farmacologia , Compostos de Anilina/síntese química , Compostos de Anilina/química , Compostos de Anilina/toxicidade , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/toxicidade , Proteínas de Bactérias/metabolismo , Benzilaminas/síntese química , Benzilaminas/química , Benzilaminas/toxicidade , Células CACO-2 , Desenho de Drogas , Eritrócitos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Células HeLa , Hemólise/efeitos dos fármacos , Humanos , Queratinócitos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Bases de Schiff/síntese química , Bases de Schiff/química , Bases de Schiff/toxicidade , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo
14.
An Acad Bras Cienc ; 91(2): e20180468, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31241699

RESUMO

This study evaluates the antibacterial, cytotoxic activities, and phytochemical composition, of Callistemon citrinus, Hibiscus rosa-sinensis and Plumbago auriculata leaves and flowers, three ornamental plants in Mexico. However, in other countries offers a range of other uses. Ethanol extracts of C. citrinus leaf and flower presented stronger antibacterial activity than the extracts obtained from the other two plants. C. citrinus leaf showed low cytotoxicity (LC50 <600 µg/mL) on the brine shrimp test, whereas the ethanol extracts of H. rosa-sinensis and P. auriculata leaves showed no cytotoxic activity. Flower extracts obtained from the three plants did no exhibit cytotoxicity. GC-MS analysis revealed that the ethanol extract of P. auriculata leaf contained lupeol triterpene and lupeol acetate, neither of them have been previously reported in this genus. Gamma sitosterol was present in the leaf and flower extracts of P. auriculata. Higher contents of linoleic and linolenic acids were found in extracts of H. rosa-sinensis leaves and flowers. The ability of the ethanol extracts of C. citrinus leaves and flowers to inhibit the growth of Gram-positive and Gram-negative bacteria indicates a potentially broad antimicrobial spectrum. Moreover, the absence of cytotoxicity suggests the potential use of this plant to treat microbial infections.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hibiscus/química , Myrtaceae/química , Extratos Vegetais/farmacologia , Plumbaginaceae/química , Animais , Antibacterianos/toxicidade , Artemia/efeitos dos fármacos , México , Testes de Sensibilidade Microbiana , Extratos Vegetais/toxicidade , Testes de Toxicidade
15.
Phytochemistry ; 164: 192-205, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31174083

RESUMO

The chemical composition of five marine microalgae (Dunaliella sp., Dunaliella salina, Chaetoceros calcitrans, Chaetoceros gracilis and Tisochrysis lutea) was investigated through nuclear magnetic resonance (NMR) spectroscopic study of the soluble material obtained by sequential extraction with hexane, ethyl acetate (AcOEt) and methanol of biomass from stationary phase cultures. Hexane extracted the major lipids present in the microalgae during the stationary phase of growth, which correspond to storage lipids. Triacylglycerols (TGs) were the only storage lipids produced by Dunaliella and Chaetoceros. In contrast, T. lutea predominantly stored polyunsaturated long-chain alkenones, with sterols also detected as minor components of the hexane extract. The molecular structure of brassicasterol was determined in T. lutea and the presence of squalene in this sample was also unequivocally detected. Monogalactosyldiacylglycerols (MGDGs) and pigments were concentrated in the AcOEt extracts. C. calcitrans and D. salina constituted an exception due to the high amount of TGs and glycerol produced, respectively, by these two strains. Chlorophylls a and b and ß-carotene were the major pigments synthesized by Dunaliella and chlorophyll a and fucoxanthin were the only pigments detected in Chaetoceros and T. lutea. Information concerning the acyl chains present in TGs and MGDGs as well as the positional distribution of acyl chains on the glycerol moiety was obtained by NMR analysis of hexane and AcOEt extracts, with results consistent with those expected for the genera studied. Fatty acid composition of TGs in the two Dunaliella strains was different, with polyunsaturated acyl chains almost absent in the storage lipids produced by D. salina. Except in C. calcitrans, the polar nature of soluble compounds was inferred through the relative extraction yield using methanol as the extraction solvent. Glycerol was the major component of this fraction for the Dunaliella strains. In T. lutea 1,4/2,5-cyclohexanetetrol (CHT) and dimethylsulfoniopropionate (DMSP) preponderated. CHT was also the major polyol present in the Chaetoceros strains in which DMSP was not detected, but prominent signals of 2,3-dihydroxypropane-1-sulfonate (DHSP) were observed in the 1H NMR spectra of methanolic extracts. The presence of DHSP confirms the production of this metabolite by diatoms. In addition, several other minor compounds (digalactosyldiacyglycerols (DGDGs), sulphoquinovosyldiacylglycerols (SQDGs), amino acids, carbohydrates, scyllo-inositol, mannitol, lactic acid and homarine) were also identified in the methanolic extracts. The antibacterial and antibiofilm activities of the extracts were tested. The AcOEt extract from C. gracilis showed a moderate antibiofilm activity.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Microalgas/química , Ressonância Magnética Nuclear Biomolecular , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antifúngicos/química , Antifúngicos/isolamento & purificação , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Microalgas/metabolismo , Testes de Sensibilidade Microbiana , Conformação Molecular
16.
J Photochem Photobiol B ; 197: 111516, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31170508

RESUMO

In the search for new therapeutic agents we have synthesized 13 new organotin(IV) carboxylate derivatives of (E)-4-((4-methoxy-2-nitrophenyl)amino)-4-oxobut-2-enoic acid. The synthesized complexes were characterized by several spectroscopic techniques. A chelating or bridging bidentate nature of the carboxylate ligand was suggested from the solid state FT-IR results. Solution state multinuclear NMR (1H, 13C and 119Sn) results reveal that the geometry around the Sn atom in triorganotin(IV) complexes is trigonal bipyramidal and in diorganotin(IV) complexes is octahedral. The ligand, (E)-4-((4-methoxy-2-nitrophenyl)amino)-4-oxobut-2-enoic acid, complex 1 and complex 2 were also analyzed by single crystal X-ray technique and the results fully supports the spectroscopic data. For 1 and 2 the geometry optimized by the single crystal X-ray analyses is distorted trigonal bipyramidal. The interaction of the studied compounds with SS-DNA was investigated by UV-Vis. Spectroscopy and Molecular docking showing an intercalative mode of binding. The evaluation of the screened compounds for cancer treatment displays even higher than that of the vincristine used as a standard drug. Similarly the performance of the tested compounds as an antileishmanial agent considers them very close in activity to the standard drug, amphotericin B. The antibacterial results show that the most of the compounds have a moderate sensitivity against the studied bacterial pathogens.


Assuntos
Complexos de Coordenação/química , Compostos Orgânicos de Estanho/química , Sítios de Ligação , Ácidos Carboxílicos/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/farmacologia , Cristalografia por Raios X , DNA/química , DNA/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Leishmania tropica/efeitos dos fármacos , Ligantes , Espectroscopia de Ressonância Magnética , Conformação Molecular , Simulação de Acoplamento Molecular , Conformação de Ácido Nucleico , Espectroscopia de Infravermelho com Transformada de Fourier
17.
J Photochem Photobiol B ; 197: 111531, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31212244

RESUMO

Environment friendly methods for the synthesis of copper nanoparticles have become a valuable trend in the current scenario. The utilization of phytochemicals from plant extracts has become a unique technology for the synthesis of nanoparticles, as they possess dual nature of reducing and capping agents to the nanoparticles. In the present investigation we have synthesized copper nanoparticles (CuNPs) using a rare medicinal plant Cissus arnotiana and evaluated their antibacterial activity against gram negative and gram positive bacteria. The morphology and characterization of the synthesized CuNPs were studied and done using UV-Visible spectroscopy at a wavelength range of 350-380 nm. XRD studies were performed for analyzing the crystalline nature; SEM and TEM for evaluating the spherical shape within the size range of 60-90 nm and AFM was performed to check the surface roughness. The biosynthesized CuNPs showed better antibacterial activity against the gram-negative bacteria, E. coli with an inhibition zone of 22.20 ±â€¯0.16 mm at 75 µg/ml. The antioxidant property observed was comparatively equal with the standard antioxidant agent ascorbic acid at a maximum concentration of 40 µg/ ml. This is the first study reported on C. arnotiana mediated biosynthesis of copper nanoparticles, where we believe that the findings can pave way for a new direction in the field of nanotechnology and nanomedicine where there is a significant potential for antibacterial and antioxidant activities. We predict that, these could lead to an exponential increase in the field of biomedical applications, with the utilization of green synthesized CuNPs, due to its remarkable properties. The highest antibacterial property was observed with gram-negative strains mainly, E. coli, due to its thin peptidoglycan layer and electrostatic interactions between the bacterial cell wall and CuNPs surfaces. Hence, CuNPs can be potent therapeutic agents in several biomedical applications, which are yet to be explored in the near future.


Assuntos
Antibacterianos/química , Antioxidantes/química , Cissus/química , Cobre/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Cissus/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Eletricidade Estática
18.
J Photochem Photobiol B ; 197: 111529, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31220803

RESUMO

The therapeutic molecules recovered from the marine biological origin are widely used for the treatment of diverse levels of infections caused by microbial pathogens. In addition, the eco-friendly preparations of nanomaterials together with the secondary metabolites' producing active microbial strains effectively suppress the spreading of the pathogenic bacteria. Considering their importance, the present study evaluated the environmental friendly synthesis of Silver nitrate nanomaterials (SNM) from the active marine Streptomyces strain Al-Dhabi-91 isolated from the Dammam region of Saudi Arabia. The obtained SNM was chemically characterized by various spectroscopic techniques such as UV, XRD, FTIR, SEM, TEM and EDAX; and its biological applications such as antimicrobial properties and antioxidant potential were recorded by DPPH methods. Biochemical and micromorphological studies together with the molecular techniques confirmed that the isolate Al-Dhabi-91 belonged to Streptomyces species. The characterization techniques confirmed that the UV spectrum showed maximum absorption peak at 305 nm indicating the plasmodium characteristics. SEM and TEM analyses evidenced 5-2 nm which are agglomerated, cool to form porous asymmetrical networks. Additionally, the FTIR spectrum showed maximum peak at 1194 cm-1 and 1394 cm-1, confirming the presence of aromatic CH bending and aromatic CC bending in the SNM. SNM exhibited prolific antibacterial activity against Gram negative pathogens, K. pneumoniae (28.33 mm) and E. coli (21.66 mm) respectively. The MIC values of SNM were significant with respect to E. faecalis (125 µg/ml), S. aureus (250 µg/ml), P. aeruginosa (125 µg/ml), K. pneumoniae (500 µg/ml) and E. coli (250 µg/ml) respectively. In addition, the antioxidant potential of the SNM was another value added importance. Especially 50 µg/ml of the nanoparticles showed 33% antioxidant potential; similarly in nitric oxide radical inhibition assay the concentration of 50 µg/ml nanoparticles showed 33% of inhibition potential. Overall, the eco-friendly synthesis of SNM from the marine Streptomyces strain Al-Dhabi-91 was an ideal active source for the treatment of infectious disease and health associated disorders.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Sedimentos Geológicos/microbiologia , Nanopartículas Metálicas/química , Prata/química , Streptomyces/química , Anti-Infecciosos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Filogenia , Arábia Saudita , Streptomyces/classificação , Streptomyces/isolamento & purificação
19.
Nat Commun ; 10(1): 2733, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227716

RESUMO

Cell wall antibiotics are crucial for combatting the emerging wave of resistant bacteria. Yet, our understanding of antibiotic action is limited, as many strains devoid of all resistance determinants display far higher antibiotic tolerance in vivo than suggested by the antibiotic-target binding affinity in vitro. To resolve this conflict, here we develop a comprehensive theory for the bacterial cell wall biosynthetic pathway and study its perturbation by antibiotics. We find that the closed-loop architecture of the lipid II cycle of wall biosynthesis features a highly asymmetric distribution of pathway intermediates, and show that antibiotic tolerance scales inversely with the abundance of the targeted pathway intermediate. We formalize this principle of minimal target exposure as intrinsic resistance mechanism and predict how cooperative drug-target interactions can mitigate resistance. The theory accurately predicts the in vivo efficacy for various cell wall antibiotics in different Gram-positive bacteria and contributes to a systems-level understanding of antibiotic action.


Assuntos
Vias Biossintéticas/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Bactérias Gram-Positivas/metabolismo , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Parede Celular/metabolismo , Bactérias Gram-Positivas/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/microbiologia , Modelos Biológicos , Uridina Difosfato Ácido N-Acetilmurâmico/análogos & derivados , Uridina Difosfato Ácido N-Acetilmurâmico/biossíntese
20.
Phys Chem Chem Phys ; 21(23): 12530-12539, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31147666

RESUMO

The emergence of antibiotic-resistance is a major concern to global human health and identification of novel antibiotics is critical to mitigate the threat. Mutacin 1140 (MU1140) is a promising antimicrobial lanthipeptide and is effective against Gram-positive bacteria. Like nisin, MU1140 targets and sequesters lipid II and interferes with its function, which results in the inhibition of bacterial cell wall synthesis, and leads to bacteria cell lysis. MU1140 contains a structurally similar thioether cage for binding the lipid II pyrophosphate as for nisin. In addition to lipid II binding, nisin is known to form membrane pores. Membrane pore formation and membrane disruption is a common mode of action for many antimicrobial peptides, including gallidermin, a lantibiotic peptide with similar structural features as MU1140. However, whether and how MU1140 and its variants can form permeable membrane pores remains to be demonstrated. In this work, we explored the potential mechanisms of membrane pore formation by performing molecular simulations of the MU1140-lipid II complex in the bacterial membrane. Our results suggest that MU1140-lipid II complexes are able to form water permeating membrane pores. We find that a single chain of MU1140 complexed with lipid II in the transmembrane region can permeate water molecules across the membrane via a single-file water transport mechanism. The ordering of the water molecules in the single-file chain region as well as the diffusion behavior is similar to those observed in other biological water channels. Multiple complexes of MU1140-lipid II in the membrane showed enhanced permeability for the water molecules, as well as a noticeable membrane distortion and lipid relocation, suggesting that a higher concentration of MU1140 assembly in the membrane can cause significant disruption of the bacterial membrane. These investigations provide an atomistic level insight into a novel mode of action for MU1140 that can be exploited to develop optimized peptide variants with improved antimicrobial properties.


Assuntos
Bacteriocinas/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Simulação de Dinâmica Molecular , Peptídeos/farmacologia , Bacteriocinas/química , Membrana Celular/efeitos dos fármacos , Bactérias Gram-Positivas/citologia , Lipídeos/química , Lipídeos/farmacologia , Testes de Sensibilidade Microbiana , Peptídeos/química , Água/química
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