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1.
Pestic Biochem Physiol ; 159: 41-50, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400783

RESUMO

Emerging fungal phytodiseases are a food security threat and novel fungicides are in an urgent need. Herein, a series of isobutyrophenone derivatives were designed and synthesized. The derivatives exhibited excellent fungicidal activities against seven fungi. The structure-activity relationship (SAR) study indicated that the introduction of a bromo group at the position 3 or 5 of the phenyl ring, as well as esterification of the 4-hydroxy with a chloroacetyl group, could substantially increase the antifungal activity and spectrum of the compounds. Among all 23 compounds, 2-bromo-3-hydroxy-4-isobutyryl-6-methylphenyl 2-chloroacetate (12b) showed the highest fungicidal activity against all seven tested fungal pathogens with EC50 values ranging from 1.22 to 39.94 µg/mL and exhibited the most potent inhibition against class II fructose-1,6-bisphosphate aldolase with an IC50 of 3.63 µM. The lead compounds were proven to be safe to NIH3T3/293 T cells and silkworm larvae, and relatively stable under different harsh conditions. Detached fruit tests showed the practical potential of lead compounds for fruit (or plant) protection. Taken together, our results indicated that the isobutyrophenone derivatives could be further optimized and developed as advanced leads for new fungicides.


Assuntos
Antifúngicos/química , Antifúngicos/metabolismo , Frutose-Bifosfato Aldolase/metabolismo , Animais , Bombyx/metabolismo , Linhagem Celular , Frutose-Bifosfato Aldolase/genética , Humanos , Larva/metabolismo , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Células NIH 3T3 , Relação Estrutura-Atividade
2.
Pestic Biochem Physiol ; 158: 175-184, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378354

RESUMO

Succinate dehydrogenase (SDH), an essential component of cellular respiratory chain and tricarboxylic acid (or Krebs) cycle, has been identified as one of the most significant targets for pharmaceutical and agrochemical. Herein, with the aim of discovery of new antifungal lead structures, a class of novel N-(4-fluoro-2-(phenylamino)phenyl)-pyrazole-4-carboxamides were designed, synthesized and evaluated for their biological activities. They were bioassayed against seven phytopathogenic fungi, Rhizoctonia solani, Phytophthora infestans, Fusarium oxysporum f. sp. vasinfectum, Botryosphaeria dothidea, Gibberella zeae, Alternaria alternate and Fusarium oxysporum f. sp. niveum. The results indicated that most of the compounds displayed good antifungal activities, especially against R. solani. Among them, compounds 7 and 12 exhibited higher antifungal activities against R. solani in vitro with EC50 value of 0.034 mg/L and 0.021 mg/L, being superior to the commercially available fungicide bixafen (EC50 = 0.043 mg/L). Pot tests against R. solani showed that in vivo EC50 values of compounds 7 (2.694 mg/L) and 12 (2.331 mg/L) were higher than that of bixafen (3.724 mg/L). In addition, inhibitory activity of compound 12 against SDH indicated compound 12 (IC50 = 1.836 mg/L) showed good inhibitory activity against SDH, being close to bixafen's inhibitory activity (IC50 = 1.222 mg/L). And, molecular modeling of the SDH-compound 12 complex suggested that compound 12 could strongly bind to and interact with the binding site of the SDH. The results of the present work showed that N-(4-fluoro-2-(phenylamino)phenyl)-pyrazole-4-carboxamides were a new fungicides for discovery of SDH inhibitors and worth further study.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Succinato Desidrogenase/metabolismo , Alternaria/efeitos dos fármacos , Alternaria/enzimologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/enzimologia , Fusarium/efeitos dos fármacos , Fusarium/enzimologia , Phytophthora infestans/efeitos dos fármacos , Phytophthora infestans/enzimologia , Rhizoctonia/efeitos dos fármacos , Rhizoctonia/enzimologia , Relação Estrutura-Atividade
3.
J Enzyme Inhib Med Chem ; 34(1): 1388-1399, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31392901

RESUMO

Fourteen novel dipeptide carboxamide derivatives bearing benzensulphonamoyl propanamide were synthesized and characterized using 1H NMR, 13C NMR, FTIR and MS spectroscopic techniques. In vivo antimalarial and in vitro antimicrobial studies were carried out on these synthesized compounds. Molecular docking, haematological analysis, liver and kidney function tests were also evaluated to assess the effect of the compounds on the organs. At 200 mg/kg body weight, 7i inhibited the multiplication of the parasite by 81.38% on day 12 of post-treatment exposure. This was comparable to the 82.34% reduction with artemisinin. The minimum inhibitory concentration (MIC) in µM ranged from 0.03 to 2.34 with 7h having MIC of 0.03 µM against Plasmodium falciparium. The in vitro antibacterial activity of the compounds against some clinically isolated bacteria strains showed varied activities with some of the new compounds showing better activities against the bacteria and the fungi more than the reference drug ciprofloxacin and fluconazole.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antimaláricos/química , Antimaláricos/farmacologia , Dipeptídeos/química , Dipeptídeos/farmacologia , Sulfonamidas/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Antimaláricos/síntese química , Bactérias/efeitos dos fármacos , Dipeptídeos/síntese química , Fungos/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Testes de Sensibilidade Parasitária , Plasmodium falciparum/efeitos dos fármacos , Ratos , Sulfonamidas/química
4.
Planta Med ; 85(13): 1054-1072, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31261421

RESUMO

The Lauraceae family is predominantly found in Asia and in the rainforests of the Americas, and consists mostly of aromatic trees. Being an essential oil producer, this family is used in the food, pharmaceutical, and cosmetic industries. This work presents a systematic review of the chemical composition and bioactivity of the essential oils from the Lauraceae family. Medline, Scielo, Web of Science, Lilacs, and Scopus were employed to identify articles published between 2000 and 2018, using "Lauraceae", "essential oil", and "biological activity" as key words. From 177 studies identified, 53 met the inclusion criteria. These studies indicated a predominance of the compounds ß-caryophyllene and 1,8-cineole in Lauraceae species, and highlighted the antioxidant, antifungal, antibacterial, and anti-inflammatory activities. Essential oils extracted from this family thus have high potential for pharmacological applications.


Assuntos
Lauraceae/química , Óleos Vegetais/farmacologia , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Óleos Vegetais/química
5.
J Enzyme Inhib Med Chem ; 34(1): 1259-1270, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31287341

RESUMO

Pyrazolylphthalimide derivative 4 was synthesized and reacted with different reagents to afford the target compounds imidazopyrazoles 5-7, pyrazolopyrimidines 9, 12, 14 and pyrazolotriazines 16, 17 containing phthalimide moiety. The prepared compounds were established by different spectral data and elemental analyses. Additionally, all synthesized derivatives were screened for their antibacterial activity against four types of Gram + ve and Gram-ve strains, and for antifungal activity against two fungi micro-organisms by well diffusion method. Moreover, the antiproliferative activity was tested for all compounds against human liver (HepG-2) cell line in comparison with the reference vinblastine. Moreover, drug-likeness and toxicity risk parameters of the newly synthesized compounds were calculated using in silico studies. The data from structure-actvity relationship (SAR) analysis suggested that phthalimide derivative bearing 3-aminopyrazolone moiety, 4 illustrated the best antimicrobial and antitumor activities and might be considered as a lead for further optimization. To investigate the mechanism of the antimicrobial and anticancer activities, enzymatic assay and molecular docking studies were carried out on E. coli topoisomerase II DNA gyrase B and VEGFR-2 enzymes.


Assuntos
Ftalimidas/química , Ftalimidas/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Ftalimidas/síntese química , Análise Espectral/métodos , Relação Estrutura-Atividade
6.
J Enzyme Inhib Med Chem ; 34(1): 1226-1232, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31307248

RESUMO

Allosamidins come from the secondary metabolites of Streptomyces species, and they have the pseudotrisaccharide structures. Allosamidins are chitinase inhibitors that can be used to study the physiological effects of chitinases in a variety of organisms. They have the novel antiasthmatic activity and insecticidal/antifungal activities. Herein, the synthesis and activities of allosamidins were summarized and analyzed.


Assuntos
Acetilglucosamina/análogos & derivados , Antiasmáticos/farmacologia , Antifúngicos/farmacologia , Inseticidas/farmacologia , Trissacarídeos/farmacologia , Acetilglucosamina/química , Acetilglucosamina/isolamento & purificação , Acetilglucosamina/farmacologia , Animais , Antiasmáticos/química , Antiasmáticos/isolamento & purificação , Antifúngicos/química , Antifúngicos/isolamento & purificação , Asma/tratamento farmacológico , Fungos/efeitos dos fármacos , Humanos , Inseticidas/química , Inseticidas/isolamento & purificação , Conformação Molecular , Mariposas/efeitos dos fármacos , Streptomyces/química , Trissacarídeos/química , Trissacarídeos/isolamento & purificação
7.
J Nanobiotechnology ; 17(1): 81, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286976

RESUMO

BACKGROUND: Magnetic nanoparticles (MNPs) are characterized by unique physicochemical and biological properties that allow their employment as highly biocompatible drug carriers. Gelsolin (GSN) is a multifunctional actin-binding protein involved in cytoskeleton remodeling and free circulating actin sequestering. It was reported that a gelsolin derived phosphoinositide binding domain GSN 160-169, (PBP10 peptide) coupled with rhodamine B, exerts strong bactericidal activity. RESULTS: In this study, we synthesized a new antibacterial and antifungal nanosystem composed of MNPs and a PBP10 peptide attached to the surface. The physicochemical properties of these nanosystems were analyzed by spectroscopy, calorimetry, electron microscopy, and X-ray studies. Using luminescence based techniques and a standard killing assay against representative strains of Gram-positive (Staphylococcus aureus MRSA Xen 30) and Gram-negative (Pseudomonas aeruginosa Xen 5) bacteria and against fungal cells (Candida spp.) we demonstrated that magnetic nanoparticles significantly enhance the effect of PBP10 peptides through a membrane-based mode of action, involving attachment and interaction with cell wall components, disruption of microbial membrane and increased uptake of peptide. Our results also indicate that treatment of both planktonic and biofilm forms of pathogens by PBP10-based nanosystems is more effective than therapy with either of these agents alone. CONCLUSIONS: The results show that magnetic nanoparticles enhance the antimicrobial activity of the phosphoinositide-binding domain of gelsolin, modulate its mode of action and strengthen the idea of its employment for developing the new treatment methods of infections.


Assuntos
Antibacterianos/química , Antifúngicos/química , Gelsolina/química , Nanopartículas de Magnetita/química , Fragmentos de Peptídeos/química , Biofilmes , Candida/efeitos dos fármacos , Membrana Celular/metabolismo , Ouro/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanoconchas/química , Plâncton , Pseudomonas aeruginosa/efeitos dos fármacos , Rodaminas/química
8.
Chem Biodivers ; 16(8): e1900204, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31298500

RESUMO

The purpose of this work was to determine the chemical composition and evaluate the antichemotactic, antioxidant, and antifungal activities of the essential oil obtained from the species Cryptocarya aschersoniana Mez, Cinnamomum amoenum (Ness & Mart.) Kosterm., and Schinus terebinthifolia Raddi, as well as the combination of C. aschersoniana essential oil and terbinafine against isolates of dermatophytes. Allo-aromadendrene, bicyclogermacrene, and germacrene B were identified as major compounds in essential oils. The essential oil of C. aschersoniana shown 100 % inhibitory effect on leukocyte migration at the concentration of 10 µg/mL while S. terebinthifolia oil presented 80.1 % inhibitory effect at the same concentration. Only S. terebinthifolia oil possessed free-radical-scavenging activity which indicates its antioxidant capacity. The essential oils were also tested against fungal isolates of dermatophyte species (Trichophyton rubrum, Trichophyton mentagrophytes, Microsporum canis and Microsporum gypseum), resulting in MIC ranging from 125 µg/mL to over 500 µg/mL. C. aschersoniana oil combined with terbinafine resulted in an additive interaction effect. In this case, the essential oil may act as a complement to conventional therapy for the topical treatment of superficial fungal infections, mainly because it is associated with an anti-inflammatory effect.


Assuntos
Anacardiaceae/química , Antifúngicos/química , Cinnamomum/química , Cryptocarya/química , Óleos Voláteis/química , Anacardiaceae/metabolismo , Antifúngicos/farmacologia , Antioxidantes/química , Candida/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Cinnamomum/metabolismo , Cryptocarya/metabolismo , Testes de Sensibilidade Microbiana , Microsporum/efeitos dos fármacos , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Óleos Voláteis/farmacologia , Extratos Vegetais/química , Trichophyton/efeitos dos fármacos
9.
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
10.
Food Chem ; 299: 125109, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31295635

RESUMO

The aim of this research is to develop, characterize and utilize a multi-layer antibacterial film using chitosan (CS) and sodium alginate (SA) as biopolymers and cinnamon essential oil (CEO) as main antibacterial ingredients. The dense cross-section of SA layer in the scanning electron microscopy (SEM) analysis verified that layer-by-layer method improved physical and mechanical properties of CS-CEO single layer film. The thermogravimetric (TGA) and fourier transform infrared (FT-IR) analysis indicated that the layer-by-layer method changed the intermolecular interaction and the thermal stability. Importantly, the multi-layer film exhibited more sustained release and higher retention rate of CEO compared CS-CEO single layer film. The multi-layer coating showed a more significant and lasting inhibition of penicillium expansion which further demonstrated that the layer-by-layer method improved the release and retention of CEO in the multiphased system. To summarize, the multilayer film system is a promising controllable release system for loading essential oils.


Assuntos
Antifúngicos/farmacologia , Cinnamomum zeylanicum/química , Malus/microbiologia , Óleos Voláteis/farmacologia , Penicillium/efeitos dos fármacos , Alginatos/química , Antifúngicos/química , Quitosana/química , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Frutas/efeitos dos fármacos , Frutas/microbiologia , Malus/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Óleos Voláteis/farmacocinética , Penicillium/patogenicidade , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termogravimetria
11.
Int J Nanomedicine ; 14: 4667-4679, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308652

RESUMO

Purpose: The pathogenicity in Candida spp was attributed by several virulence factors such as production of tissue damaging extracellular enzymes, germ tube formation, hyphal morphogenesis and establishment of drug resistant biofilm. The objective of present study was to investigate the effects of silver nanoparticles (AgNPs) on growth, cell morphology and key virulence attributes of Candida species. Methods: AgNPs were synthesized by the using seed extract of Syzygium cumini (Sc), and were characterized by UV-Vis spectrophotometer, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), and transmission electron microscopy (TEM). ScAgNPs were used to evaluate their antifungal and antibacterial activity as well as their potent inhibitory effects on germ tube and biofilm formation and extracellular enzymes viz. phospholipases, proteinases, lipases and hemolysin secreted by Candida spp. Results: The MICs values of ScAgNPs were ranged from 0.125-0.250 mg/ml, whereas the MBCs and MFCs were 0.250 and 0.500 mg/ml, respectively. ScAgNPs significantly inhibit the production of phospholipases by 82.2, 75.7, 78.7, 62.5, and 65.8%; proteinases by 82.0, 72.0, 77.5, 67.0, and 83.7%; lipase by 69.4, 58.8, 60.0, 42.9, and 65.0%; and hemolysin by 62.8, 69.7, 67.2, 73.1, and 70.2% in C. albicans, C. tropicalis, C. dubliniensis, C. parapsilosis and C. krusei, respectively, at 500 µg/ml. ScAgNPs inhibit germ tube formation in C. albicans up to 97.1% at 0.25 mg/ml. LIVE/DEAD staining results showed that ScAgNPs almost completely inhibit biofilm formation in C. albicans. TEM analysis shows that ScAgNPs not only anchored onto the cell surface but also penetrated and accumulated in the cytoplasm that causes severe damage to the cell wall and cytoplasmic membrane. Conclusion: To summarize, the biosynthesized ScAgNPs strongly suppressed the multiplication, germ tube and biofilm formation and most importantly secretion of hydrolytic enzymes (viz. phospholipases, proteinases, lipases and hemolysin) by Candia spp. The present research work open several avenues of further study, such as to explore the molecular mechanism of inhibition of germ tubes and biofilm formation and suppression of production of various hydrolytic enzymes by Candida spp.


Assuntos
Antifúngicos/farmacologia , Candida/crescimento & desenvolvimento , Candida/patogenicidade , Nanopartículas Metálicas/química , Prata/farmacologia , Antifúngicos/química , Biofilmes/efeitos dos fármacos , Candida/citologia , Candida/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Proteínas Hemolisinas/metabolismo , Humanos , Hidrólise , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Syzygium/química , Virulência/efeitos dos fármacos , Fatores de Virulência
12.
Pestic Biochem Physiol ; 157: 230-236, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153473

RESUMO

Zirconium oxide nanoparticles (ZrONPs) were synthesized and evaluated for their ability to induce root rot resistance in cucumber and direct antifungal activity against Rhizoctonia solani. Resistance induction was investigated using real-time polymerase chain reaction (RT-PCR) and the effect of ZrONPs on the growth of cucumber plants was investigated. The results showed that ZrONPs at a concentration level of 100 µg/L significantly inhibited the growth of Rhizoctonia solani (86.6%) relative to untreated control under laboratory conditions. Cucumber plants treated with ZrONPs showed reduction in the severity of root rot disease under greenhouse (34-46%) and field conditions (52-56%) compared with non-treated control plants. Cucumber plants treated with ZrONPs expressed regulatory and defense genes involved in the salicylic acid (SA) and jasmonic acid (JA)/ethylene (ET) signaling pathways with 7-8 folds higher than the control. Treatment of cucumber with ZrONPs and carboxin + thiram significantly improved cucumber growth and yield characters. Therefore, using ZrONPs could be a new strategy to control this pathogen and considered the first report.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Cucumis sativus/microbiologia , Nanopartículas/química , Rhizoctonia/efeitos dos fármacos , Zircônio/química
13.
Pestic Biochem Physiol ; 157: 45-52, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153476

RESUMO

Herein, we describe the enhanced antifungal activity of silver nanoparticles biosynthesized by cell free filtrate of Trichoderma viride (MTCC 5661) in comparison to chemically synthesized silver nanoparticles (CSNP) of similar shape and size. Biosynthesized silver nanoparticles (BSNP) enhanced the reduction in dry weight by 20 and 48.8% of fungal pathogens Fusarium oxysporum and Alternaria brassicicola respectively in comparison to their chemical counterparts (CSNP). Nitroblue tetrazolium and Propidium iodide staining demonstrated the higher generation of superoxide radicals lead to higher death in BSNP treated fungus in comparison to CSNP. Scanning electron microscopy of A. brassicicola revealed the osmotic imbalance and membrane disintegrity to be major cause for fungal cell death after treatment with BSNP. To gain an insight into the mechanistic aspect of enhanced fungal cell death after treatment of BSNP in comparison to CSNP, stress responses and real time PCR analysis was carried out with A. brassicicola. It revealed that generation of ROS, downregulation of antioxidant machinery and oxidative enzymes, disruption of osmotic balance and cellular integrity, and loss of virulence are the mechanisms employed by BSNP which establishes them as superior antifungal agent than their chemical counterparts. With increasing drug resistance and ubiquitous presence of fungal pathogens in plant kingdom, BSNP bears the candidature for new generation of antifungal agent.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Nanopartículas Metálicas/química , Doenças das Plantas/microbiologia , Prata/química , Alternaria/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Oxirredução/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Superóxidos/metabolismo
14.
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
15.
Food Chem Toxicol ; 131: 110559, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31176927

RESUMO

The family Piperaceae is known for presenting in its species flavoring, healing and antimicrobial properties among others. The objective of the present study was: to study the chemical profile of the essential oil of Piper rivinoides (EOPR); to analyze its anti-bacterial and antifungal potential, as well as to evaluate the antifungal and antibiotic-modifying capacity. The chemical constituents were identified by gas chromatography with flame ionization detector (GC-FID), allowing the identification of 7 constituents of a total of 86.99%. E-Isoelemicin was identified as the main constituent of petroleum (40.81%). Clinically relevant MIC results were obtained against fungi in which the inhibitory concentration remained <256 µg/mL, as for Candida albicans 4127 (217.6 µg/mL). The association of EOPR with an antifungal showed a high synergistic affinity against the strains of C. tropicalis 40042 and 4262. We concluded that no intrinsic EOPR activity was observed at any concentrations tested against bacteria. However, EOPR associated with Gentamicin acted synergistically against S. aureus 10 and Escherichia coli 06, but with Erythromycin there was a synergistic effect against Escherichia coli 06, and antagonism with norfloxacin.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Óleos Voláteis/farmacologia , Piper/química , Antibacterianos/análise , Antibacterianos/química , Antifúngicos/análise , Antifúngicos/química , Candida albicans/efeitos dos fármacos , Sinergismo Farmacológico , Eritromicina/farmacologia , Escherichia coli/efeitos dos fármacos , Gentamicinas/farmacologia , Testes de Sensibilidade Microbiana , Óleos Voláteis/análise , Óleos Voláteis/química , Folhas de Planta/química , Staphylococcus aureus/efeitos dos fármacos
17.
Chem Biol Interact ; 308: 294-303, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31158333

RESUMO

The emergence of multidrug resistant (MDR) pathogens is a global threat and has created problems in providing adequate treatment of many infectious diseases. Although the conventional antimicrobial agents are quite effective against several pathogens, yet there is a need for more effective antimicrobial agents against MDR pathogens. Herbal drugs and phytochemicals have been used for their effective antimicrobial activity from ancient times and there is an increasing trend for development of plant based natural products for the prevention and treatment of pathogenic diseases. One of the strategies for effective resistance modification is the use of antimicrobial agent-phytochemical combinations that will neutralize the resistance mechanism, enabling the drug to still be effective against resistant microbes. These phytochemicals can work by several strategies, such as inhibition of target modifying and drug degrading enzymes or as efflux pumps inhibitors. A plethora of herbal extracts, essential oils and isolated pure compounds have been reported to act synergistically with existing antibiotics, antifungals and chemotherapeutics and augment the activity of these drugs. Considerable increases in the susceptibility pattern of several microbes towards the natural antimicrobials and their combinations were observed as indicated by significant decline in minimum inhibitory concentrations. This review paper summarizes the current developments regarding synergistic interactions of plant extracts and isolated pure compounds in combination with existing antibacterial, antifungal agents and chemotherapeutics. The effect of these agents on the susceptibility patterns of these pathogens and possible mechanisms of action are described in detail. In conclusion, many phytochemicals in combination with existing drugs were found to act as resistance modifying agents and proper combinations may rescue the efficacy of important lifesaving antimicrobial agents.


Assuntos
Anti-Infecciosos/farmacologia , Resistência a Medicamentos/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Antifúngicos/química , Antifúngicos/farmacologia , Antivirais/química , Antivirais/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Vírus de DNA/efeitos dos fármacos , Sinergismo Farmacológico , Fungos/efeitos dos fármacos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/metabolismo , beta-Lactamases/química , beta-Lactamases/metabolismo
18.
Eur J Med Chem ; 178: 515-529, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31207463

RESUMO

Carvacrol (CAR), a natural monoterpene particularly abundant in plants belonging to the Lamiaceae family, has recently attracted much attention for its many biological properties (antioxidant, anti-inflammatory, neuroprotective, antitumour, antibacterial, and several others). However, CAR has poor chemical-physical properties (low water solubility and high volatility), which hamper its potential pharmacological uses. In this paper, the synthesis and antimicrobial evaluation of 23 carvacrol derivatives (WSCP1-23) against a panel of selected gram-positive and gram-negative bacteria are reported. Using the prodrug approach, CAR hydrophilic (WSCP1-17) and lipophilic prodrugs (WSCP18-23) were prepared. Notably, CAR water solubility was increased by using polar neutral groups (such as natural amino acids) with the aim of improving oral drug delivery. On the other hand, CAR lipophilic prodrugs, obtained by prenylation of CAR hydroxyl group, were designed to promote membrane permeation and oral absorption. Our results revealed that WSCP1-3, showing the highest water solubility (>1700-fold compared to that of CAR), possessed good antibacterial activity against gram-negative bacteria with MIC values comparable to those of CAR and antifungal properties against different species of Candida. WSCP18-19 were the most promising prodrugs, showing good antibacterial profiles against gram-positive bacteria by interfering with the biofilm formation of Staphylococcus aureus and Staphylococcus epidermidis. Moreover, WSCP18-19 resulted more stable in simulated fluids and human plasma than WSCP1-3. Toxicity studies performed on human erythrocytes and HaCaT cells revealed that all WSCPs were not toxic at the tested concentrations.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Monoterpenos/farmacologia , Pró-Fármacos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Candida/efeitos dos fármacos , Relação Dose-Resposta a Droga , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Monoterpenos/síntese química , Monoterpenos/química , Pró-Fármacos/síntese química , Pró-Fármacos/química , Solubilidade , Relação Estrutura-Atividade
19.
Chem Commun (Camb) ; 55(49): 6964-6996, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31140997

RESUMO

Noble metals comprise any of several metallic chemical elements that are outstandingly resistant to corrosion and oxidation, even at elevated temperatures. This group is not strictly defined, but the tentative list includes ruthenium, rhodium, palladium, silver, osmium, iridium, platinum and gold, in order of atomic number. The emerging properties of noble metal nanoparticles are attracting huge interest from the translational scientific community and have led to an unprecedented expansion of research and exploration of applications in biotechnology and biomedicine. Noble metal nanomaterials can be synthesised both by top-down and bottom up approaches, as well as via organism-assisted routes, and subsequently modified appropriately for the field of use. Nanoscale analogues of gold, silver, platinum, and palladium in particular, have gained primary importance owing to their excellent intrinsic properties and diversity of applications; they offer unique functional attributes, which are quite unlike the bulk material. Modulation of noble metal nanoparticles in terms of size, shape and surface functionalisation has endowed them with unusual capabilities and manipulation at the chemical level, which can lead to changes in their electrical, chemical, optical, spectral and other intrinsic properties. Such flexibility in multi-functionalisation delivers 'Ockham's razor' to applied biomedical science. In this feature article, we highlight recent advances in the adaptation of noble metal nanomaterials and their biomedical applications in therapeutics, diagnostics and sensing.


Assuntos
Antibacterianos/química , Antifúngicos/química , Pesquisa Biomédica , Nanopartículas Metálicas/química , Metais Pesados/química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Humanos , Metais Pesados/farmacologia , Ressonância de Plasmônio de Superfície
20.
Mar Drugs ; 17(5)2019 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-31035452

RESUMO

Rare actinomycetes are prolific in the marine environment; however, knowledge about their diversity, distribution and biochemistry is limited. Marine rare actinomycetes represent a rather untapped source of chemically diverse secondary metabolites and novel bioactive compounds. In this review, we aim to summarize the present knowledge on the isolation, diversity, distribution and natural product discovery of marine rare actinomycetes reported from mid-2013 to 2017. A total of 97 new species, representing 9 novel genera and belonging to 27 families of marine rare actinomycetes have been reported, with the highest numbers of novel isolates from the families Pseudonocardiaceae, Demequinaceae, Micromonosporaceae and Nocardioidaceae. Additionally, this study reviewed 167 new bioactive compounds produced by 58 different rare actinomycete species representing 24 genera. Most of the compounds produced by the marine rare actinomycetes present antibacterial, antifungal, antiparasitic, anticancer or antimalarial activities. The highest numbers of natural products were derived from the genera Nocardiopsis, Micromonospora, Salinispora and Pseudonocardia. Members of the genus Micromonospora were revealed to be the richest source of chemically diverse and unique bioactive natural products.


Assuntos
Actinobacteria/química , Organismos Aquáticos/química , Produtos Biológicos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Antimaláricos/química , Antimaláricos/isolamento & purificação , Antimaláricos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antiparasitários/química , Antiparasitários/isolamento & purificação , Antiparasitários/farmacologia , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação
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