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1.
Molecules ; 26(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34500631

RESUMO

The 'core' metabolome of the Bacteroidetes genus Chitinophaga was recently discovered to consist of only seven metabolites. A structural relationship in terms of shared lipid moieties among four of them was postulated. Here, structure elucidation and characterization via ultra-high resolution mass spectrometry (UHR-MS) and nuclear magnetic resonance (NMR) spectroscopy of those four lipids (two lipoamino acids (LAAs), two lysophosphatidylethanolamines (LPEs)), as well as several other undescribed LAAs and N-acyl amino acids (NAAAs), identified during isolation were carried out. The LAAs represent closely related analogs of the literature-known LAAs, such as the glycine-serine dipeptide lipids 430 (2) and 654. Most of the here characterized LAAs (1, 5-11) are members of a so far undescribed glycine-serine-ornithine tripeptide lipid family. Moreover, this study reports three novel NAAAs (N-(5-methyl)hexanoyl tyrosine (14) and N-(7-methyl)octanoyl tyrosine (15) or phenylalanine (16)) from Olivibacter sp. FHG000416, another Bacteroidetes strain initially selected as best in-house producer for isolation of lipid 430. Antimicrobial profiling revealed most isolated LAAs (1-3) and the two LPE 'core' metabolites (12, 13) active against the Gram-negative pathogen M. catarrhalis ATCC 25238 and the Gram-positive bacterium M. luteus DSM 20030. For LAA 1, additional growth inhibition activity against B. subtilis DSM 10 was observed.


Assuntos
Aminoácidos/química , Aminoácidos/farmacologia , Bacteroidetes/metabolismo , Glicerofosfolipídeos/química , Glicerofosfolipídeos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Técnicas de Tipagem Bacteriana/métodos
2.
Nanoscale ; 13(33): 13923-13942, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34477675

RESUMO

Owing to their peculiar oxidative effect, silver cations (Ag+) are well known for their antimicrobial properties and explored as therapeutic agents for biomedical applications. Size control with improved dispersion and stability are the key factors of Ag NPs (silver nanoparticles) to be used in biomedical applications. Silver based nano-materials are highly efficient due to their biological, chemical and physical properties in comparison with bulk silver. Atomic scale fabrication is achieved by rearranging the internal components of a material, in turn, influencing the mechanical, electrical, magnetic, thermal and chemical properties. For instance, size and shape have a strong impact on the optical, thermal and catalytic properties of Ag NPs. Such properties can be tuned by controlling the surface/volume ratio of Ag nanostructures with a small size (ideally <100 nm), in turn showing peculiar biological activity different from that of bulk silver. Silver nanomaterials such as nanoparticles, thin films and nanorods can be synthesized by various physical, chemical and biological methods whose most recent implementations will be described in this review. By controlling the structure-functionality relationship, silver based nano-materials have high potential for commercialization in biomedical applications. Antimicrobial, antifungal, antiviral, and anti-inflammatory Ag NPs can be applied in several fields such as pharmaceutics, sensors, coatings, cosmetics, wound healing, bio-labelling agents, antiviral drugs, and packaging.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Nanoestruturas , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Prata
3.
BMC Res Notes ; 14(1): 348, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34496958

RESUMO

OBJECTIVE: Papaver decaisnei Hochst. & Steud. Ex Elkan and Papaver glaucum Boiss. & Hausskn. growing wild in Northern Iraq have been historically used for medicinal purposes. In this study, both species were evaluated for their alkaloid content and antimicrobial activities. RESULTS: Alkaloids were extracted and isolated by preparative thin-layer chromatography (TLC). Identification was carried out by comparing spectral data (UV and 1H-NMR) and TLC Rf values with those of authentic samples. Two alkaloids, proapaorphine-type mecambrine and aporphine-type roemerine were isolated from P. decaisnei. Two benzylisoquinoline type alkaloids papaverine (major alkaloid) and palaudine as well as aporphine-type N-methylasimilobine have been obtained in P. glaucum. Both P. glaucum and P. decaisnei extracts revealed strong antimicrobial activity on Pseudomonas aeruginosa ATCC 27853 and Enterococcus faecalis ATCC 29212. Collectively these results indicate that P. glaucum and P. decaisnei are promising sources of alkaloids that could further be investigated for medicinal purposes.


Assuntos
Alcaloides , Anti-Infecciosos , Papaver , Alcaloides/farmacologia , Anti-Infecciosos/farmacologia , Cromatografia em Camada Delgada , Extratos Vegetais/farmacologia
4.
Int J Mol Sci ; 22(17)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34502431

RESUMO

Transparent materials used for facial protection equipment provide protection against microbial infections caused by viruses and bacteria, including multidrug-resistant strains. However, transparent materials used for this type of application are made of materials that do not possess antimicrobial activity. They just avoid direct contact between the person and the biological agent. Therefore, healthy people can become infected through contact of the contaminated material surfaces and this equipment constitute an increasing source of infectious biological waste. Furthermore, infected people can transmit microbial infections easily because the protective equipment do not inactivate the microbial load generated while breathing, sneezing or coughing. In this regard, the goal of this work consisted of fabricating a transparent face shield with intrinsic antimicrobial activity that could provide extra-protection against infectious agents and reduce the generation of infectious waste. Thus, a single-use transparent antimicrobial face shield composed of polyethylene terephthalate and an antimicrobial coating of benzalkonium chloride has been developed for the next generation of facial protective equipment. The antimicrobial coating was analyzed by atomic force microscopy and field emission scanning electron microscopy with elemental analysis. This is the first facial transparent protective material capable of inactivating enveloped viruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in less than one minute of contact, and the methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis. Bacterial infections contribute to severe pneumonia associated with the SARS-CoV-2 infection, and their resistance to antibiotics is increasing. Our extra protective broad-spectrum antimicrobial composite material could also be applied for the fabrication of other facial protective tools such as such as goggles, helmets, plastic masks and space separation screens used for counters or vehicles. This low-cost technology would be very useful to combat the current pandemic and protect health care workers from multidrug-resistant infections in developed and underdeveloped countries.


Assuntos
Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Equipamento de Proteção Individual , Anti-Infecciosos/química , Bacteriófago phi 6/efeitos dos fármacos , Compostos de Benzalcônio/química , Compostos de Benzalcônio/farmacologia , COVID-19/patologia , COVID-19/virologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Polietilenotereftalatos/química , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/isolamento & purificação , Staphylococcus epidermidis/efeitos dos fármacos
5.
J Agric Food Chem ; 69(36): 10731-10740, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34469689

RESUMO

Although the antimicrobial, nutritional, and health-promoting properties of royal jelly (RJ) have been widely confirmed, the effects of storage temperature and time on RJ quality remain to be further explored. Herein, the antimicrobial and proteomic dynamics of RJ stored under different conditions were comprehensively investigated to identify consistent and sensitive markers of RJ degradation. We confirmed the negative correlation between antimicrobial properties and increased the storage temperature and duration in RJ. Using surface plasmon resonance, we showed the protein degradation-induced conformation changes in RJ, which reflected the overall variation in RJ proteins caused by the storage conditions. Further proteomic and western blotting analyses demonstrated the sensitivity and reliability of major RJ protein 4 (MRJP4) as a measure of temperature- and time-dependent RJ changes. Based on these results, we developed a colloidal gold immunoassay strip for MRJP4 detection, providing a reliable, simple, and rapid method for the evaluation of RJ freshness.


Assuntos
Anti-Infecciosos , Proteoma , Anti-Infecciosos/farmacologia , Ácidos Graxos , Proteômica , Reprodutibilidade dos Testes , Temperatura
6.
Soft Matter ; 17(35): 8001-8021, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34525154

RESUMO

The use of hydrogels has garnered significant interest as biomaterial and drug delivery platforms for anti-infective applications. For decades antimicrobial peptides have been heralded as a much needed new class of antimicrobial drugs. Self-assembling peptide hydrogels with inherent antimicrobial ability have recently come to the fore. However, their fundamental antimicrobial properties, selectivity and mechanism of action are relatively undefined. This review attempts to establish a link between antimicrobial efficacy; the self-assembly process; peptide-membrane interactions and mechanical properties by studying several reported peptide systems: ß-hairpin/ß-loop peptides; multidomain peptides; amphiphilic surfactant-like peptides and ultrashort/low molecular weight peptides. We also explore their role in the formation of amyloid plaques and the potential for an infection etiology in diseases such as Alzheimer's. We look briefly at innovative methods of gel characterization. These may provide useful tools for future studies within this increasingly important field.


Assuntos
Anti-Infecciosos , Hidrogéis , Anti-Infecciosos/farmacologia , Materiais Biocompatíveis , Peptídeos , Tensoativos
7.
Enzyme Microb Technol ; 150: 109888, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34489041

RESUMO

Owing to the probiotic origin, lipases-derived from the Lactobacilli sp. are considered to be promising biomaterials for in vivo applications. On a different note, poly(ε-caprolactone) (PCL)-an FDA-approved polymer for implantable applications-lacks inherent antimicrobial property, because of which suitable modifications are required to render it with bactericidal activity. Here, we employ Lactobacillus amylovorous derived lipase to surface derivatize the PCL films with silver that is a highly efficient inorganic broad-spectrum antimicrobial substance. Two different surface functionalization strategies have been employed over the alkaline hydrolyzed PCL films towards this purpose: In the first strategy, lipase-capped silver nanoparticles (Ag NPs) have been synthesized in a first step, which have been covalently immobilized over the activated carboxylic groups on the PCL film surface in a subsequent step. In the second strategy, the lipase was covalently immobilized over the activated carboxylic groups of the PCL film surface in the first step, over which silver was deposited in the second step using the dip-coating method. While the characterization study using X-ray photoelectron spectroscopy (XPS) has revealed the successful derivatization of silver over the PCL film, the surface characterization using field-emission scanning electron microscopy (FE-SEM) study has shown a distinct morphological change with higher silver loading in both strategies. The antimicrobial studies employing E. coli have revealed 100 % inhibition in the bacterial growth in 4-6 h with the Ag NPs-immobilized PCL films as opposed to >8 h with those prepared through the dip-coating method. Additionally, the cytotoxicity assay using mouse fibroblast cells has shown that the PCL films immobilized with lipase-capped Ag NPs exhibit high cell compatibility, similar to that of pristine PCL film, and thereby making it suitable for in vivo applications.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Animais , Anti-Infecciosos/farmacologia , Escherichia coli , Lactobacillus acidophilus , Lipase , Camundongos , Poliésteres , Prata/farmacologia
8.
Molecules ; 26(15)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34361550

RESUMO

Efficient use of herbicides for plant protection requires the application of auxiliary substances such as surfactants, stabilizers, wetting or anti-foaming agents, and absorption enhancers, which can be more problematic for environment than the herbicides themselves. We hypothesized that the combination of sulfonylurea (iodosulfuron-methyl) anion with inexpensive, commercially available quaternary tetraalkylammonium cations could lead to biologically active ionic liquids (ILs) that could become a convenient and environment-friendly alternative to adjuvants. A simple one-step synthesis allowed for synthesizing iodosulfuron-methyl based ILs with high yields ranging from 88 to 96% as confirmed by UV, FTIR, and NMR. The obtained ILs were found to possess several favorable properties compared to the currently used sodium salt iodosulfuron-methyl, such as adjustable hydrophobicity (octanol-water partition coefficient) and enhanced stability in aqueous solutions, which was supported by molecular calculations showing cation-anion interaction energies. In addition, soil mobility and volatility of ILs were more beneficial compared to the parental herbicide. Herbicidal activity tests toward oil-seed rape and cornflower revealed that ILs comprising at least one alkyl chain in the decyl to octadecyl range had similar or better efficacy compared to the commercial preparation without addition of any adjuvant. Furthermore, results of antimicrobial activity indicated that they were practically harmless or slightly toxic toward model soil microorganisms such as Pseudomonas putida and Bacillus cereus.


Assuntos
Anti-Infecciosos/química , Herbicidas/química , Líquidos Iônicos/química , Sulfonamidas/química , Compostos de Sulfonilureia/química , Tensoativos/química , Anti-Infecciosos/farmacologia , Bacillus cereus/crescimento & desenvolvimento , Herbicidas/farmacologia , Pseudomonas putida/crescimento & desenvolvimento , Compostos de Sulfonilureia/farmacologia
9.
Molecules ; 26(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443608

RESUMO

In order to develop novel bioactive substances with potent activities, some new valine-derived compounds incorporating a 4-(phenylsulfonyl)phenyl fragment, namely, acyclic precursors from N-acyl-α-amino acids and N-acyl-α-amino ketones classes, and heterocycles from the large family of 1,3-oxazole-based compounds, were synthesized. The structures of the new compounds were established using elemental analysis and spectral (UV-Vis, FT-IR, MS, NMR) data, and their purity was checked by reversed-phase HPLC. The newly synthesized compounds were evaluated for their antimicrobial and antibiofilm activities, for toxicity on D. magna, and by in silico studies regarding their potential mechanism of action and toxicity. The 2-aza-3-isopropyl-1-[4-(phenylsulfonyl)phenyl]-1,4-butanedione 4b bearing a p-tolyl group in 4-position exhibited the best antibacterial activity against the planktonic growth of both Gram-positive and Gram-negative strains, while the N-acyl-α-amino acid 2 and 1,3-oxazol-5(4H)-one 3 inhibited the Enterococcus faecium biofilms. Despite not all newly synthesized compounds showing significant biological activity, the general scaffold allows several future optimizations for obtaining better novel antimicrobial agents by the introduction of various substituents on the phenyl moiety at position 5 of the 1,3-oxazole nucleus.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Cetonas/síntese química , Cetonas/farmacologia , Oxazóis/síntese química , Oxazóis/farmacologia , Anti-Infecciosos/química , Biofilmes/efeitos dos fármacos , Técnicas de Química Sintética , Cetonas/química , Oxazóis/química , Relação Estrutura-Atividade
10.
Molecules ; 26(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443614

RESUMO

Kombucha is a traditional beverage of sweetened black tea fermented with a symbiotic association of acetic acid bacteria and yeasts. In this study, kombucha fermented beverage (KFB) appeared to include nine chemical groups (alcohols, acids, lactones, condensed heterocyclic compounds, antibiotics, esters, aldehydes, fatty acids, and alkaloids) of many bioactive metabolites, as elucidated by gas chromatography-mass spectrometry (GC-MS) and IR spectra. The fermented metabolic components of KFB seem collectively to act in a synergistic action giving rise to the antimicrobial activity. Four types of kombucha preparations (fermented, neutralized, heat-treated and unfermented) were demonstrated with respect to their antimicrobial activity against some pathogenic bacterial and fungal strains using agar well diffusion assay. KFB exerted the strongest antimicrobial activities when compared with neutralized and heat-treated kombucha beverages (NKB and HKB). Staphylococcus aureus ATCC6538 (S. aureus) and Escherichia coli ATCC11229 (E. coli) were the organisms most susceptible to the antimicrobial activity of kombucha beverage preparations. Finally, the KFB preparation showed remarkable inhibitory activity against S. aureus and E. coli bacteria in a brain heart infusion broth and in some Egyptian fruit juices (apple, guava, strawberry, and tomato). These data reveal that kombucha is not only a prophylactic agent, but also appears to be promising as a safe alternative biopreservative, offering protection against pathogenic bacteria and fungi.


Assuntos
Anti-Infecciosos/análise , Anti-Infecciosos/farmacologia , Alimentos e Bebidas Fermentados/análise , Alimentos e Bebidas Fermentados/microbiologia , Concentração de Íons de Hidrogênio
11.
Plant Foods Hum Nutr ; 76(3): 281-291, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34427882

RESUMO

Ginkgo biloba L. is an ancient plant relic, which is known as a "living fossil", and is widely cultivated in China. This plant with medical potential and health benefits has drawn the attention of researchers. Ginkgo seeds are rich in protein. Ginkgo seed proteins (GSPs) have good functional properties over many other seed proteins, which have the potential to be utilized as food ingredients. Moreover, GSP contains no restricted amino acids and is easy to be separated. Several GSP isolate with various bioactivities, such as antimicrobial and antioxidative activities, have been purified and evaluated for their bioactive potential. In this review, the separation methods and bioactivities of GSP were summarized, physicochemical characteristics and functional properties were comprehensively reviewed and compared with other seed proteins. Some food applications of GSP were also briefly introduced. Besides, some suggestions and prospects were discussed in this review.


Assuntos
Anti-Infecciosos , Ginkgo biloba , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , China , Sementes
12.
Gen Dent ; 69(5): 34-37, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34424209

RESUMO

This study evaluated the antimicrobial activity of root canal filling pastes commonly used in primary teeth: iodoform paste, zinc oxide-eugenol (ZOE), and analytical grade calcium hydroxide (Ca[OH]2). The materials were evaluated in the following 6 combinations: iodoform paste (Rifocort [prednisolone + rifampicin] + iodoform + camphorated paramonochlorophenol); zinc oxide + eugenol in a proportion of 1:3; zinc oxide + eugenol in a proportion of 1:5; Ca(OH)2 + water; iodoform paste + ZOE (1:3) + Ca(OH)2; and ZOE (1:3) + Ca(OH)2. Chlorhexidine gel (0.2%) served as the positive control. A commercial strain of Enterococcus faecalis (ATCC 25175) was plated in petri dishes containing 10 mL of brain-heart infusion agar culture medium with a hole in the center. The filling pastes (3 g) were manipulated and inserted in the hole. The plates were incubated at 37°C for 48 hours, and then the inhibition zone associated with each paste was measured. The experiments were carried out in triplicate (n = 3 per group). The data were submitted to analysis of variance and Tukey tests (P < 0.05). Iodoform paste resulted in the largest mean (SD) inhibition zone, 7.06 (0.74) mm. The smallest was obtained with Ca(OH)2 + water, the mean (SD) of 0.00 (0.00) mm indicating that these specimens did not form an inhibition zone. The ZOE pastes in proportions of 1:3 and 1:5 resulted in statistically similar mean (SD) inhibition zones of 1.86 (0.50) and 1.30 (0.18) mm, respectively (P > 0.05). Of the test materials, the combination of iodoform paste + ZOE + Ca(OH)2 presented the second largest inhibition zone, 6.27 (3.08) mm, significantly different from that of the non-iodoform pastes (P < 0.05). It can be concluded that iodoform paste, alone or in combination with ZOE + Ca(OH)2, demonstrates high antimicrobial activity, while the combination of ZOE + Ca(OH)2 demonstrates moderate activity.


Assuntos
Anti-Infecciosos , Materiais Restauradores do Canal Radicular , Anti-Infecciosos/farmacologia , Criança , Cavidade Pulpar , Humanos , Odontopediatria , Materiais Restauradores do Canal Radicular/farmacologia , Obturação do Canal Radicular
13.
Molecules ; 26(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34443356

RESUMO

Within the unavoidable variability of various origins in the characteristics of essential oils, the aim of this study was to evaluate the effect of the distillation time on the chemical composition and biological activity of Cannabis sativa essential oils (EOs). The dry inflorescences came from Carmagnola, Kompolti, Futura 75, Gran Sasso Kush and Carmagnola Lemon varieties from Abruzzo region (Central Italy), the last two being new cultivar here described for the first time. EOs were collected at 2 h and 4 h of distillation; GC/MS technique was applied to characterize their volatile fraction. The EOs were evaluated for total polyphenol content (TPC), antioxidant capacity (AOC) and antimicrobial activity against food-borne pathogens and spoilage bacteria. The time of distillation particularly influenced EOs chemical composition, extracting more or less terpenic components, but generally enriching with minor sesquiterpenes and cannabidiol. A logical response in ratio of time was observed for antioxidant potential, being the essential oils at 4 h of distillation more active than those distilled for 2 h, and particularly Futura 75. Conversely, except for Futura 75, the effect of time on the antimicrobial activity was variable and requires further investigations; nevertheless, the inhibitory activity of all EOs against Pseudomonas fluorescens P34 was an interesting result.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Cannabis/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Polifenóis/análise , Fatores de Tempo
14.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361759

RESUMO

Croton ferrugineus Kunth is an endemic species of Ecuador used in traditional medicine both for wound healing and as an antiseptic. In this study, fresh Croton ferrugineus leaves were collected and subjected to hydrodistillation for extraction of the essential oil. The chemical composition of the essential oil was determined by gas chromatography equipped with a flame ionization detector and gas chromatography coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against three Gram-positive bacteria, one Gram-negative bacterium and one dermatophyte fungus. The radical scavenging properties of the essential oil was evaluated by means of DPPH and ABTS assays. The chemical analysis allowed us to identify thirty-five compounds representing more than 99.95% of the total composition. Aliphatic sesquiterpene hydrocarbon trans-caryophyllene was the main constituent with 20.47 ± 1.25%. Other main compounds were myrcene (11.47 ± 1.56%), ß-phellandrene (10.55 ± 0.02%), germacrene D (7.60 ± 0.60%), and α-humulene (5.49 ± 0.38%). The essential oil from Croton ferrugineus presented moderate activity against Candida albicans (ATCC 10231) with an MIC of 1000 µg/mL, a scavenging capacity SC50 of 901 ± 20 µg/mL with the ABTS method, and very strong antiglucosidase activity with an IC50 of 146 ± 20 µg/mL.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Croton/química , Inibidores Enzimáticos/química , Óleos Voláteis/química , Folhas de Planta/química , Monoterpenos Acíclicos/química , Monoterpenos Acíclicos/isolamento & purificação , Alcenos/química , Alcenos/isolamento & purificação , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Monoterpenos Cicloexânicos/química , Monoterpenos Cicloexânicos/isolamento & purificação , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Sesquiterpenos Monocíclicos/química , Sesquiterpenos Monocíclicos/isolamento & purificação , Picratos/antagonistas & inibidores , Sesquiterpenos Policíclicos/química , Sesquiterpenos Policíclicos/isolamento & purificação , Sesquiterpenos de Germacrano/química , Sesquiterpenos de Germacrano/isolamento & purificação , Ácidos Sulfônicos/antagonistas & inibidores , alfa-Glucosidases/química
15.
Curr Microbiol ; 78(10): 3609-3619, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34432112

RESUMO

Due to the deaths from infections caused by multidrug-resistant microorganisms worldwide, the World Health Organization considers antibiotic resistance to be a critical global public health problem. Bacterial resistance mechanisms are diverse and can be acquired through the overexpression of transmembrane proteins that are called efflux pumps, which act by expelling drugs from the intracellular environment, thereby preventing their action and contributing to the severity of infections. Efflux pumps are one of the main mechanisms of bacterial resistance, and it is important to identify new molecules that are capable of inhibiting the action of efflux pumps and circumvent the problem of resistance linked to the expression of these transmembrane proteins. The plants are promising candidates for obtaining biologically active substances, such as essential oils, with antimicrobial activity and inhibitors of efflux pumps, which can help in the resensitization of bacterial strains resistant to antibiotics. Therefore, this review aims to present the recently reported inhibitory activity of essential oils against bacterial pathogens that produce efflux pumps.


Assuntos
Anti-Infecciosos , Infecções Bacterianas , Óleos Voláteis , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Farmacorresistência Bacteriana Múltipla , Humanos , Óleos Voláteis/farmacologia
16.
Molecules ; 26(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34443313

RESUMO

Nowadays, products of natural origin with health-promoting properties are increasingly more common. Research shows that fruit vinegars can be a source of compounds with antioxidant activity. Research on the total antioxidant capacity, total phenolic content, and antimicrobial properties against Staphylococcus aureus, Escherichia coli, and Candida albicans of grape vinegars were conducted. Moreover, gas chromatography was used to measure acetic acid content in the vinegars. The research material consisted of vinegars produced from five different grape varieties. For each variety, two variants were prepared: with and without the addition of sugar in the fermentation process. The highest antimicrobial activity against all micro-organisms was observed in vinegar produced from Solaris grapes with added sugar. The highest polyphenol content was observed in vinegar produced from the Prior grape variety with added sugar and the highest total antioxidant capacity is the Johanniter grape variety with added sugar. The vinegars examined in this study differed, depending on grape variety, in terms of antimicrobial properties, antioxidant capacity, total phenolic content, as well as acetic acid content. Sugar addition caused significant differences in the antioxidant capacity of vinegar samples.


Assuntos
Ácido Acético/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/análise , Antioxidantes/farmacologia , Fermentação , Vitis/química , Cromanos/metabolismo , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Polônia , Polifenóis/análise
17.
Molecules ; 26(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34443457

RESUMO

Curcumin extracted from the rhizome of Curcuma Longa has been used in therapeutic preparations for centuries in different parts of the world. However, its bioactivity is limited by chemical instability, water insolubility, low bioavailability, and extensive metabolism. In this study, the coaxial electrospinning technique was used to produce both poly (ε-caprolactone) (PCL)-curcumin and core-shell nanofibers composed of PCL and curcumin in the core and poly (lactic acid) (PLA) in the shell. Morphology and physical properties, as well as the release of curcumin were studied and compared with neat PCL, showing the formation of randomly oriented, defect-free cylindrical fibers with a narrow distribution of the dimensions. The antibacterial and antibiofilm potential, including the capacity to interfere with the quorum-sensing mechanism, was evaluated on Pseudomonas aeruginosa PAO1, and Streptococcus mutans, two opportunistic pathogenic bacteria frequently associated with infections. The reported results demonstrated the ability of the Curcumin-loading membranes to inhibit both PAO1 and S. mutans biofilm growth and activity, thus representing a promising solution for the prevention of biofilm-associated infections. Moreover, the high biocompatibility and the ability to control the oxidative stress of damaged tissue, make the synthesized membranes useful as scaffolds in tissue engineering regeneration, helping to accelerate the healing process.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes , Curcumina/farmacologia , Infecções/microbiologia , Nanofibras/química , Engenharia Tecidual , Biofilmes/efeitos dos fármacos , Compostos de Bifenilo/química , Morte Celular/efeitos dos fármacos , Linhagem Celular , Liberação Controlada de Fármacos , Sequestradores de Radicais Livres/farmacologia , Humanos , Cinética , Testes de Sensibilidade Microbiana , Picratos/química , Poliésteres/química , Percepção de Quorum/efeitos dos fármacos , Termogravimetria
18.
Int J Mol Sci ; 22(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34445378

RESUMO

(1) Background: Several properties of silver nanoparticles (AgNPs), such as cytotoxic, anticancer, and antimicrobial activities, have been subjects of intense research; however, important aspects such as nanoparticle aggregation are generally neglected, although a decline in colloidal stability leads to a loss of the desired biological activities. Colloidal stability is affected by pH, ionic strength, or a plethora of biomolecules that interact with AgNPs under biorelevant conditions. (2) Methods: As only a few studies have focused on the relationship between aggregation behavior and the biological properties of AgNPs, here, we have systematically evaluated this issue by completing a thorough analysis of sterically (via polyvinyl-pyrrolidone (PVP)) stabilized AgNPs that were subjected to different circumstances. We assessed ultraviolet-visible light absorption, dynamic light scattering, zeta potential measurements, in vitro cell viability, and microdilution assays to screen both colloidal stability as well as bioactivity. (3) Results: The results revealed that although PVP provided outstanding biorelevant colloidal stability, the chemical stability of AgNPs could not be maintained completely with this capping material. (4) Conclusion: These unexpected findings led to the realization that stabilizing materials have more profound importance in association with biorelevant applications of nanomaterials than just being simple colloidal stabilizers.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Povidona/química , Prata/farmacologia , Anti-Infecciosos/química , Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Difusão Dinâmica da Luz , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Prata/química
19.
Molecules ; 26(16)2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34443685

RESUMO

Recognition of pathogen-associated molecular patterns (PAMPs) by appropriate pattern recognition receptors (PRRs) is a key step in activating the host immune response. The role of a fungal PAMP is attributed to ß-1,3-glucan. The role of α-1,3-glucan, another fungal cell wall polysaccharide, in modulating the host immune response is not clear. This work investigates the potential of α-1,3-glucan as a fungal PAMP by analyzing the humoral immune response of the greater wax moth Galleria mellonella to Aspergillus niger α-1,3-glucan. We demonstrated that 57-kDa and 61-kDa hemolymph proteins, identified as ß-1,3-glucan recognition proteins, bound to A. niger α-1,3-glucan. Other hemolymph proteins, i.e., apolipophorin I, apolipophorin II, prophenoloxidase, phenoloxidase activating factor, arylphorin, and serine protease, were also identified among α-1,3-glucan-interacting proteins. In response to α-1,3-glucan, a 4.5-fold and 3-fold increase in the gene expression of antifungal peptides galiomicin and gallerimycin was demonstrated, respectively. The significant increase in the level of five defense peptides, including galiomicin, corresponded well with the highest antifungal activity in hemolymph. Our results indicate that A. niger α-1,3-glucan is recognized by the insect immune system, and immune response is triggered by this cell wall component. Thus, the role of a fungal PAMP for α-1,3-glucan can be postulated.


Assuntos
Aspergillus/química , Glucanos/metabolismo , Interações Hospedeiro-Patógeno , Mariposas/microbiologia , Padrões Moleculares Associados a Patógenos/metabolismo , Animais , Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Corpo Adiposo/efeitos dos fármacos , Corpo Adiposo/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Hemolinfa/metabolismo , Imunização , Larva , Mariposas/efeitos dos fármacos , Mariposas/genética , Ligação Proteica/efeitos dos fármacos , Análise de Sobrevida
20.
Molecules ; 26(16)2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34443693

RESUMO

The multi-step synthesis, physico-chemical characterization, and biological activity of novel valine-derived compounds, i.e., N-acyl-α-amino acids, 1,3-oxazol-5(4H)-ones, N-acyl-α-amino ketones, and 1,3-oxazoles derivatives, bearing a 4-[(4-chlorophenyl)sulfonyl]phenyl moiety are reported here. The structures of the newly synthesized compounds were confirmed by spectral (UV-Vis, FT-IR, MS, 1H- and 13C-NMR) data and elemental analysis results, and their purity was determined by RP-HPLC. The new compounds were assessed for their antimicrobial activity and toxicity to aquatic crustacean Daphnia magna. Also, in silico studies regarding their potential mechanism of action and toxicity were performed. The antimicrobial evaluation revealed that the 2-{4-[(4-chlorophenyl)sulfonyl]benzamido}-3-methylbutanoic acid and the corresponding 1,3-oxazol-5(4H)-one exhibited antimicrobial activity against Gram-positive bacterial strains and the new 1,3-oxazole containing a phenyl group at 5-position against the C. albicans strain.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/toxicidade , Ácido Benzoico/síntese química , Ácido Benzoico/toxicidade , Simulação por Computador , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Ácido Benzoico/química , Ácido Benzoico/farmacologia , Biofilmes/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Testes de Sensibilidade Microbiana , Espectroscopia de Prótons por Ressonância Magnética , Testes de Toxicidade
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