Propolis, a resin produced by bees, is widely used in industrial products, including food, cosmetics, supplements, and pharmaceuticals. Extracts (ethanolic and hydroethanolic) and fractions, yielded ...by accelerated solvent extraction methodology, were obtained from different samples of Brazilian brown propolis (BBP). They were evaluated for antioxidant capacity, antibacterial, antibiofilm, and anti-Trichomonas vaginalis activities. The metabolomics profiling was determined by LC-DAD-MS and an innovative application of statistical analyses (univariate and chemometrics) was applied to correlate chemical compounds with biological activities. Eighty-six compounds were identified, including phenylpropanoic acids, flavonoids, chlorogenic acids, and prenylated phenylpropanoic acids. Propolis-fractions killed about 93% of Staphylococcus aureus in biofilm (at concentration of 125 μg/mL), showed activity against T. vaginalis with MIC at 400 μg/mL and significative antioxidant capacity (IC50 2.32–3.80 μg/mL). Propolis extracts and fractions did not show antibacterial and antibiofilm activities against Pseudomonas aeruginosa. The prenylated phenylpropanoic acids positively correlated with both the antibiofilm (S. aureus) and anti-T. vaginalis activities, such as the metabolites artepillin C, drupanin, and baccharin.
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•Brown Brazilian propolis compounds identified by LC-DAD-MS.•Compounds from brown Brazilian propolis kill S. aureus into biofilm and Trichomonas vaginalis.•Positive correlations (Pearson's) between prenylated phenylpropanoid acid derivatives and biological activities.
This study describes the first screening of Caatinga plants against Staphylococcus epidermidis and confirms several ethnopharmacological reports. The evaluation presented herein can contribute to ...identify new antibiofilm and antibacterial products from traditional Brazilian medicine. Display omitted
► 20 plants were effective in preventing Staphylococcus epidermidis biofilm formation. ► High antibiofilm activity was detected in plants of Fabaceae. ► 13 plants were able to inhibit S. epidermidis planktonic bacterial growth. ► Polyphenols, coumarins, steroids and terpenes as possible active compounds. ► Traditional Brazilian medicine is a valuable tool to discovery new prototypes.
Medicinal plants from the Caatinga, a Brazilian xeric shrubland, are used in folk medicine to treat infections. These ethnopharmacological data can contribute to obtaining new antimicrobial/antibiofilm extracts and natural product prototypes for the development of new drugs. The aim of this study was to investigate the antibiofilm and antibacterial activities of 45 aqueous extracts from 24 Caatinga plant species.
The effect of aqueous extracts on planktonic cells and on biofilm formation by Staphylococcus epidermidis was studied by the OD600 absorbance and by the crystal violet assay, respectively. Scanning electron microscopy (SEM) was used to generate comparative images of extract-treated and untreated biofilms. Chromatographic analyses were performed to characterize the active extracts.
The in vitro screening, at 0.4mg/mL and 4.0mg/mL, showed 20 plants effective in preventing biofilm formation and 13 plants able to inhibit planktonic bacterial growth. SEM images demonstrated distinct profiles of bacterial adhesion, matrix production and cell morphology according to different treatments and surfaces. The phytochemical analysis of the selected active extracts indicates the polyphenols, coumarins, steroids and terpenes as possible active compounds.
This study describes the first antibiofilm and antibacterial screening of Caatinga plants against S. epidermidis. The evaluation presented in this study confirms several ethnopharmacological reports and can be utilized to identify new antibiofilm and antibacterial products against S. epidermidis from traditional Brazilian medicine.
•PgTeL is an antifungal agent against C. albicans and C. krusei.•The lectin caused energy collapse and oxidative stress in yeast cells.•Treatment with PgTeL led to damage of cell wall and rupture of ...yeast cells.•PgTeL showed antibiofilm effect on C. albicans at sub-inhibitory concentrations.•PgTeL effects can be linked to the bioactivities attributed to P. granatum fruit.
The pomegranate (Punica granatum) sarcotesta contains a chitin-binding lectin (PgTeL) with antibacterial activity against human pathogenic species. In this work, the structural stability of PgTeL was evaluated by fluorimetric analysis and the lectin was evaluated for cytotoxicity to human peripheral blood mononuclear cells (PBMCs) and antifungal activity against Candida albicans and Candida krusei. PgTeL folding was impaired when lectin was incubated at pH≥6.0. On the other hand, the lectin did not undergo unfolding even when heated at 100°C. PgTeL (1, 10, and 100μg/mL) was not cytotoxic to PBMCs. Antifungal activity was detected for C. albicans (MIC: 25μg/mL; MFC: 50μg/mL) and C. krusei (MIC and MFC of 12.5μg/mL). Treatment of yeast cells with PgTeL resulted in decrease of intracellular ATP content even at sub-inhibitory concentrations (½MIC and ¼MIC) and induced lipid peroxidation. In addition, PgTeL damaged the integrity of fungal cell wall of both species, with more pronounced effects in C. krusei. The lectin showed significant antibiofilm activity on C. albicans at sub-inhibitory concentrations (0.195 and 0.39μg/mL). In conclusion, PgTeL is an anti-Candida agent whose action mechanism involves oxidative stress, energetic collapse, damage to the cell wall and rupture of yeast cells.
Trichomoniasis is the most common non-viral sexually transmitted disease worldwide and can lead to serious consequences in reproductive health, cancer, and HIV acquisition. The current approved ...treatment present adverse effects and drug resistance data on this neglected parasitic infection is underestimated. Chalcones are a family of molecules that present biological applications, such as activity against many pathogenic organisms including protozoan pathogens. Chalcone (
1
) and three amino-analogues (
2
–
4
) were synthesized by Claisen–Schmidt condensation reaction and had their activity evaluated against the parasitic protozoan
Trichomonas vaginalis
. This bioassay indicated the presence and position of the amino group on ring A was crucial for anti-
T. vaginalis
activity. Among these, 3′-aminochalcone (
3
) presented the most potent effect and showed high cytotoxicity against human vaginal cells. On the other hand,
3
was not able to exhibit toxicity against
Galleria mellonella
larvae, as well as the hemolytic effect on human erythrocytes. Trophozoites of
T. vaginalis
were treated with
3
, and did not present significant reactive oxygen species (ROS) accumulation, but induced a significantly higher ROS accumulation in human neutrophils after co-incubation.
T. vaginalis
pyruvate:ferredoxin oxidoreductase (PFOR) and β-tubulin gene expression was not affected by
3
.
Despite many advances, biomaterial-associated infections continue to be a major clinical problem. In order to minimize bacterial adhesion, material surface modifications are currently being ...investigated and natural products possess large potential for the design of innovative surface coatings. We report the bioguided phytochemical investigation of Pityrocarpa moniliformis and the characterization of tannins by mass spectrometry. It was demonstrated that B-type linked proanthocyanidins-coated surfaces, here termed Green coatings, reduced Gram-positive bacterial adhesion and supported mammalian cell spreading. The proposed mechanism of bacterial attachment inhibition is based on electrostatic repulsion, high hydrophilicity and the steric hindrance provided by the coating that blocks bacterium-substratum interactions. This work shows the applicability of a prototype Green-coated surface that aims to promote necessary mammalian tissue compatibility, while reducing bacterial colonization.
Lycorine is an Amaryllidaceae alkaloid that presents anti-
Trichomonas vaginalis
activity.
T. vaginalis
causes trichomoniasis, the most common non-viral sexually transmitted infection. The modulation ...of
T. vaginalis
purinergic signaling through the ectonucleotidases, nucleoside triphosphate diphosphohydrolase (NTPDase), and ecto-5′-nucleotidase represents new targets for combating the parasite. With this knowledge, the aim of this study was to investigate whether NTPDase and ecto-5′-nucleotidase inhibition by lycorine could lead to extracellular ATP accumulation. Moreover, the lycorine effect on the reactive oxygen species (ROS) production by neutrophils and parasites was evaluated as well as the alkaloid toxicity. The metabolism of purines was assessed by HPLC. ROS production was measured by flow cytometry. Cytotoxicity against epithelial vaginal cells and fibroblasts was tested, as well as the hemolytic effect of lycorine and its in vivo toxicity in
Galleria mellonella
larvae. Our findings showed that lycorine caused ATP accumulation due to NTPDase inhibition. The alkaloid did not affect the ROS production by
T. vaginalis
; however, it increased ROS levels in neutrophils incubated with lycorine-treated trophozoites. Lycorine was cytotoxic against vaginal epithelial cells and fibroblasts; conversely, it was not hemolytic neither exhibited toxicity against the in vivo model of
G. mellonella
larvae. Overall, besides having anti-
T. vaginalis
activity, lycorine modulates ectonucleotidases and stimulates neutrophils to secrete ROS. This mechanism of action exerted by the alkaloid could enhance the susceptibility of
T. vaginalis
to host immune cell, contributing to protozoan clearance.
Sixteen triterpenoids with various skeletal types, five phenylpropanoid derivatives, and two flavonoids were isolated from a propolis sample produced by Apis mellifera collected in the Atlantic ...Forest of Midwest Brazil. Among these compounds, six triterpenes, namely 3β,20R‐dihydroxylanost‐24‐en‐3‐yl‐palmitate, (23E)‐25‐methoxycycloartan‐23‐en‐3‐one, 24‐methylenecycloartenone, epi‐lupeol, epi‐α‐amyrin, and epi‐β‐amyrin are being reported for the first time in propolis, while cycloartenone, (E)‐cinnamyl benzoate, and (E)‐cinnamyl cinnamate are new findings in Brazilian propolis. The presence of cycloartane‐ and lanostane‐type triterpenoids, the latter being a class of compounds of restricted distribution in propolis worldwide, has not been reported in propolis from Midwest Brazil until now. The ethyl acetate phase obtained from the ethanol extract was effective in preventing biofilm formation by Staphylococcus aureus, with an inhibition rate of about 96 % at 0.5 mg.mL−1, and with quercetin isolated as one of its active constituents. In contrast, the hexane phase exhibited notable antibacterial activity against Pseudomonas aeruginosa, inhibiting bacterial growth by 92 % at 0.5 mg.mL−1; however, none of the triterpenoids isolated from this phase proved active against this pathogen. The ethanol extract was neither toxic nor mutagenic at the concentrations tested, as determined by the in vivo SMART assay on Drosophila melanogaster, even under conditions of high metabolic activation.
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Human and bovine trichomoniasis are sexually transmitted diseases (STD) caused by Trichomonas vaginalis and Tritrichomonas foetus, respectively. Human trichomoniasis is the most ...common non-viral STD in the world and bovine trichomoniasis causes significant economic losses to breeders. Considering the significant impact of the infections caused by these protozoa and the treatment failures, the search for new therapeutic alternatives becomes crucial. In this study the effect of diamines and amino alcohols in the in vitro viability of trichomonads was evaluated. Screening demonstrated the high activity of diamine 4 against these protozoa. Although cytotoxicity against HMVII cell line and slight hemolysis were observed in vitro, the compound showed no toxic effect on the Galleria mellonella in vivo model. Importantly, diamine 4 was active against both trichomonads species at 6h and 24h of incubation, and these effects was reverted by putrescine, a polyamine, suggesting competition for the same metabolic pathway. These findings indicate that the mechanism of action of diamine 4 is through the polyamine metabolism, a pathway distinct from that presented by metronidazole, the drug usually used to treat trichomoniasis and to which resistance is widely reported. These data demonstrate the importance of diamines as potential novel candidates as anti-T. vaginalis and anti-T. foetus agents.
complex has been increasingly recognized as a nosocomial pathogen representing the third major Enterobacteriaceae species involved with infections. This study aims to evaluate virulence and ...antimicrobial susceptibility of subpopulations generated from macrocolonies of NDM-1 producing
clinical isolates. Biofilm was quantified using crystal violet method and fimbrial genes were investigated by PCR. Susceptibility of antimicrobials, alone and combined, was determined by minimum inhibitory concentration and checkerboard assays, respectively. Virulence and efficacy of antimicrobials were evaluated in
larvae. Importantly, we verified that some subpopulations that originate from the same macrocolony present different biofilm production ability and distinct susceptibility to meropenem due to the loss of
encoding plasmid. A more in-depth study was performed with the 798 macrocolony subpopulations. Type 3 fimbriae were straightly related with biofilm production; however, virulence in larvae was not statistically different among subpopulations. Triple combination with meropenem-rifampicin-polymyxin B showed in vitro synergistic effect against all subpopulations; while in vivo this treatment showed different efficacy rates for 798-1S and 798-4S subpopulations. The ability of multidrug resistant
isolates in generating bacterial subpopulations presenting different susceptible and virulence mechanisms are worrisome and may explain why these infections are hardly overcome.
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