RESUMEN

Endophytic bacteria found in marine macroalgae have been studied for their potential antimicrobial activity, consequently, they could serve as a valuable source of bioactive compounds to control pathogenic bacteria, yeasts, and fungi. Algae endophytic bacteria were isolated from Caulerpa sp., Ulva sp., Ahnfeltiopsis sp., and Chondracantus chamissoi from Yacila and Cangrejo Beaches (Piura, Peru). Antimicrobial assays against pathogenic bacteria were evaluated using cross-culture, over-plate, and volatile organic compound tests. Afterward, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of selected crude extracts were determined, also ITS molecular analysis, antifungal activity, and PCR of iturin, fengycin, and surfactin genes were performed for bacteria strains exhibiting better activity. Forty-six algae endophytic bacteria were isolated from algae. Ten strains inhibited gram-positive pathogenic bacteria (Enterococcus faecalis, Staphylococcus epidermidis, S. aureus, and Listeria monocytogenes), and 12 inhibited gram-negative bacteria (Escherichia coli and Salmonella enteric sv typhimurium). Bacteria with better activity belong to Bacillus sp., Kluyvera ascorbata, Pantoea agglomerans, Leclercia adecarboxylata, and Enterobacter sp., which only four showed antifungal activities against Candida albicans, C. tropicalis, Colletotrichium sp., Fusarium sp., Fusarium oxysporum, and Alternaria sp. Furthermore, K. ascorbata YAFE21 and Bacillus sp. YCFE4 exhibited iturin and fengycin genes. The results indicate that the algae endophytic bacteria found in this study, particularly K. ascorbata YAFE21, Bacillus sp. YCFR6, L. adecarboxylata CUFE2, Bacillus sp. YUFE8, Enterobacter sp. YAFL1, and P. agglomerans YAFL6, could be investigated as potential producers of antimicrobial compounds due to their broad activity against various microorganisms.

Asunto(s)

Endófitos , Pruebas de Sensibilidad Microbiana , Algas Marinas , Endófitos/aislamiento & purificación , Endófitos/genética , Endófitos/metabolismo , Endófitos/química , Endófitos/clasificación , Algas Marinas/microbiología , Bacterias/efectos de los fármacos , Bacterias/aislamiento & purificación , Bacterias/clasificación , Antiinfecciosos/farmacología , Antiinfecciosos/aislamiento & purificación , Antibacterianos/farmacología , Antibacterianos/aislamiento & purificación , Antifúngicos/farmacología , Antifúngicos/aislamiento & purificación , Hongos/efectos de los fármacos , Hongos/aislamiento & purificación , Hongos/clasificación , Bacterias Gramnegativas/efectos de los fármacos , Ulva/microbiología , Caulerpa/microbiología , Bacterias Grampositivas/efectos de los fármacos

RESUMEN

Staphylococcus aureus, particularly multi-drug resistant strains, presents significant challenges in dairy farming due to its role in causing bovine mastitis, which leads to substantial economic losses and limited treatment options. Seeking alternative therapies, we investigated the potential of a topical formulation derived from the medicinal herb Salvia officinalis to combat S. aureus growth and biofilms associated with bovine mastitis. Through systematic extraction in different solvents and fractionation by column chromatography, we isolated and identified three key multicyclic terpenoids-ferruginol, sugiol, and sclareol-exhibiting significant antimicrobial activity. The formulation effectively inhibited biofilm formation, with minimum inhibitory concentration (MIC) values ranging from 0.09 to 0.74 mg ml-1 against clinical S. aureus strains, comparable to or lower than those of the pure compounds. Moreover, it displayed robust anti-adhesive properties, reducing biofilm formation by 20%-79% at subinhibitory concentrations. Furthermore, the formulation successfully disrupted pre-existing biofilms, achieving reductions ranging from 30% to 82%. Cytotoxicity assays confirmed the safety of the formulation on mammary epithelial cells, with cell viability maintained at 100% at MIC. Our findings underscore the therapeutic potential of Sa. officinalis-derived compounds in managing bovine mastitis caused by S. aureus, emphasizing their antimicrobial efficacy and safety profile.

Asunto(s)

Antibacterianos , Biopelículas , Mastitis Bovina , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Plantas Medicinales , Salvia officinalis , Staphylococcus aureus , Terpenos , Staphylococcus aureus/efectos de los fármacos , Biopelículas/efectos de los fármacos , Animales , Bovinos , Salvia officinalis/química , Terpenos/farmacología , Terpenos/química , Terpenos/aislamiento & purificación , Mastitis Bovina/microbiología , Mastitis Bovina/tratamiento farmacológico , Extractos Vegetales/farmacología , Extractos Vegetales/química , Antibacterianos/farmacología , Antibacterianos/aislamiento & purificación , Antibacterianos/química , Plantas Medicinales/química , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/tratamiento farmacológico , Femenino

RESUMEN

Wounds or chronic injuries are associated with high medical costs so, develop healing-oriented drugs is a challenge for modern medicine. The identification of new therapeutic alternatives focuses on the use of natural products. Therefore, the main goal of this study was to evaluate the healing potential and anti-inflammatory mechanism of action of extracts and the main compounds derived from Myrciaria plinioides D. Legrand leaves. The antimicrobial activity of leaf extracts was analyzed. Cell viability, cytotoxicity and genotoxicity of plant extracts and compounds were also assessed. Release of pro- and anti-inflammatory cytokines and TGF-ß by ELISA, and protein expression was determined by Western Blot. The cell migration and cell proliferation of ethanol and aqueous leaf extracts and p-coumaric acid, quercetin and caffeic acid compounds were also evaluated. The aqueous extract exhibited antibacterial activity and, after determining the safety concentrations in three assays, we showed that this extract induced p38-α MAPK phosphorylation and the same extract and the p-coumaric acid decreased COX-2 and caspase-3, -8 expression, as well as reduced the TNF-α release and stimulated the IL-10 in RAW 264.7 cells. In L929 cells, the extract and p-coumaric acid induced TGF-ß release, besides increasing the process of cell migration and proliferation. These results suggested that the healing properties of Myrciaria plinioides aqueous extract can be associated to the presence of phenolic compounds, especially p-coumaric acid, and/or glycosylated metabolites.

Asunto(s)

Antiinflamatorios , Movimiento Celular , Extractos Vegetales , Hojas de la Planta , Cicatrización de Heridas , Extractos Vegetales/farmacología , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/aislamiento & purificación , Cicatrización de Heridas/efectos de los fármacos , Ratones , Células RAW 264.7 , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Línea Celular , Citocinas/metabolismo , Myrtaceae/química , Ácidos Cumáricos/farmacología , Ácidos Cumáricos/aislamiento & purificación , Antibacterianos/farmacología , Antibacterianos/aislamiento & purificación

RESUMEN

To assess the antibacterial effectiveness of Lippia macrophylla essential oil (LMEO) against multidrug-resistant Acinetobacter baumannii isolates, both as a standalone treatment and in combination with conventional antibiotics. LMEO demonstrated a significant inhibitory effect on the growth of A. baumannii, with a minimum inhibitory concentration (MIC) below 500 µg/mL. Notably, LMEO was capable of reversing the antibiotic resistance of clinical isolates or reducing their MIC values when used in combination with antibiotics, showing synergistic (FICI≤0.5) or additive effects. The combination of LMEO and imipenem was particularly effective, displaying synergistic interactions for most isolates. Ultrastructural analyses supported these findings, revealing that the combination of LMEO+ceftazidime compromised the membrane integrity of the Acb35 isolate, leading to cytoplasmic leakage and increased formation of Outer Membrane Vesicles (OMVs). Taken together our results point for the use of LMEO alone or in combination as an antibacterial agent against A. baumannii. These findings offer promising avenues for utilizing LMEO as a novel antibacterial strategy against drug-resistant infections in healthcare settings, underscoring the potential of essential oils in enhancing antibiotic efficacy.

Asunto(s)

Acinetobacter baumannii , Antibacterianos , Farmacorresistencia Bacteriana Múltiple , Lippia , Pruebas de Sensibilidad Microbiana , Aceites Volátiles , Acinetobacter baumannii/efectos de los fármacos , Aceites Volátiles/farmacología , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Lippia/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Humanos , Relación Dosis-Respuesta a Droga

RESUMEN

Periodontitis is clinically characterized by destruction of the tooth support system and tooth loss. Porphyromonas gingivalis (Pg) plays a dominant role in periodontitis. Fractions and isolated compounds from an acetone-water extract of the roots of Limonium brasiliense (Lb) were tested in vitro for their anti-adhesive capacity against Pg on human KB buccal cells, influence on gingipains, the main virulence factors of Pg, and biofilm formation. Fractions EAF and FLB7 (50 µg/mL) reduced the bacterial adhesion of Pg to KB cells significantly (63 resp. 70%). The proanthocyanidin samarangenin A inhibited the adhesion (72%, 30 µM), samarangenin B (71%, 20 µM), and the flavan-3-ol epigallocatechin-3-O-gallate (79%, 30 µM). Fraction AQF, representing hydrophilic compounds, reduced the proteolytic activity of Arginin-specific gingipain (IC50 12.78 µg/mL). Fractions EAF and FLB7, characterized by lipohilic constituents, inhibited Arg-gingipain (IC50 3 µg/mL). On Lysine-specific gingipain, AQF has an IC50 15.89, EAF 14.15, and FLB7 6 µg/mL. The reduced bacterial adhesion is due to a strong interaction of proanthocyanidins with gingipains. AQF, EAF, and FLB7 significantly inhibited biofilm formation: IC50 11.34 (AQF), 11.66 (EAF), and 12.09 µg/mL (FLB7). In silico analysis indicated, that the polyphenols act against specific targets of Pg, not affecting mammalian cells. Therefore, Lb might be effective for prevention of periodontal disease by influencing virulence factors of Pg.

Asunto(s)

Adhesinas Bacterianas , Adhesión Bacteriana , Biopelículas , Cisteína Endopeptidasas , Cisteína-Endopeptidasas Gingipaínas , Extractos Vegetales , Plumbaginaceae , Porphyromonas gingivalis , Factores de Virulencia , Biopelículas/efectos de los fármacos , Porphyromonas gingivalis/efectos de los fármacos , Humanos , Adhesinas Bacterianas/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Plumbaginaceae/química , Raíces de Plantas/química , Proantocianidinas/farmacología , Proantocianidinas/aislamiento & purificación , Células KB , Antibacterianos/farmacología , Antibacterianos/aislamiento & purificación , Antibacterianos/química , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación

RESUMEN

This work presents the development, synthesis, and application of a layered double hydroxide (LDH) coupled to magnetic particles for the removal of antibiotics as tetracyclines (TC´s): tetracycline (TC), chlortetracycline (CT), oxytetracycline (OT), and doxycycline (DT) from milk samples. The LDH synthesis conditions, reaction time (30-90 min), molar ratios Mg2+/Al3+ (7:1-1:7), interlayer anion (NO3-, Cl-, CO32-, and dodecyl sulphate (DS-)) were evaluated. Under synthesis conditions (reaction time of 30 min, Mg2+/Al3+ molar ratio of 7:1, and DS- as interlayer anion), the LDH was coupled in a magnetic solid phase microextraction (MSPµE) methodology. At the optimal extraction conditions (pH 6, 5 min of contact time, 10 mg of adsorbent), a removal percentage of 99.0 % was obtained for each tetracycline. FTIR, TGA, SEM, and adsorption isotherms were employed to characterize the optimal adsorbent. Each experiment was corroborated by large-volume sample stacking capillary electrophoresis (LVSS-CE). The adsorbent was applied directly to positive milk samples (previously tested) for TC´s removal.

Asunto(s)

Hidróxidos , Leche , Tetraciclinas , Leche/química , Animales , Tetraciclinas/aislamiento & purificación , Tetraciclinas/análisis , Tetraciclinas/química , Hidróxidos/química , Adsorción , Microextracción en Fase Sólida/métodos , Antibacterianos/aislamiento & purificación , Antibacterianos/química , Antibacterianos/análisis , Dióxido de Silicio/química

RESUMEN

The skin of fish is a physicochemical barrier that is characterized by being formed by cells that secrete molecules responsible for the first defense against pathogenic organisms. In this study, the biological activity of peptides from mucus of Seriola lalandi and Seriolella violacea were identified and characterized. To this purpose, peptide extraction was carried out from epidermal mucus samples of juveniles of both species, using chromatographic strategies for purification. Then, the peptide extracts were characterized to obtain the amino acid sequence by mass spectrometry. Using bioinformatics tools for predicting antimicrobial and antioxidant activity, 12 peptides were selected that were chemically produced by simultaneous synthesis using the Fmoc-Tbu strategy. The results revealed that the synthetic peptides presented a random coil or extended secondary structure. The analysis of antimicrobial activity allowed it to be discriminated that four peptides, named by their synthesis code 5065, 5069, 5070, and 5076, had the ability to inhibit the growth of Vibrio anguillarum and affected the copepodite stage of C. rogercresseyi. On the other hand, peptides 5066, 5067, 5070, and 5077 had the highest antioxidant capacity. Finally, peptides 5067, 5069, 5070, and 5076 were the most effective for inducing respiratory burst in fish leukocytes. The analysis of association between composition and biological function revealed that the antimicrobial activity depended on the presence of basic and aromatic amino acids, while the presence of cysteine residues increased the antioxidant activity of the peptides. Additionally, it was observed that those peptides that presented the highest antimicrobial capacity were those that also stimulated respiratory burst in leukocytes. This is the first work that demonstrates the presence of functional peptides in the epidermal mucus of Chilean marine fish, which provide different biological properties when the fish face opportunistic pathogens.

Asunto(s)

Acuicultura , Peces , Moco , Animales , Moco/química , Chile , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Péptidos/farmacología , Péptidos/química , Péptidos/aislamiento & purificación , Vibrio/efectos de los fármacos , Epidermis/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación

RESUMEN

Polyphenols from agro-food waste represent a valuable source of bioactive molecules that can be recovered to be used for their functional properties. Another option is to use them as starting material to generate molecules with new and better properties through semi-synthesis. A proanthocyanidin-rich (PACs) extract from avocado peels was used to prepare several semi-synthetic derivatives of epicatechin by acid cleavage in the presence of phenol and thiol nucleophiles. The adducts formed by this reaction were successfully purified using one-step centrifugal partition chromatography (CPC) and identified by chromatographic and spectroscopic methods. The nine derivatives showed a concentration-dependent free radical scavenging activity in the DPPH assay. All compounds were also tested against a panel of pathogenic bacterial strains formed by Listeria monocytogenes (ATCC 7644 and 19115), Staphylococcus aureus (ATCC 9144), Escherichia coli (ATCC 11775 and 25922), and Salmonella enterica (ATCC 13076). In addition, adducts were tested against two no-pathogenic strains, Limosilactobacillus fermentum UCO-979C and Lacticaseibacillus rhamnosus UCO-25A. Overall, thiol-derived adducts displayed antimicrobial properties and, in some specific cases, inhibited biofilm formation, particularly in Listeria monocytogenes (ATCC 7644). Interestingly, phenolic adducts were inactive against all the strains and could not inhibit its biofilm formation. Moreover, depending on the structure, in specific cases, biofilm formation was strongly promoted. These findings contribute to demonstrating that CPC is a powerful tool to isolate new semi-synthetic molecules using avocado peels as starting material for PACc extraction. These compounds represent new lead molecules with antioxidant and antimicrobial activity.

Asunto(s)

Antioxidantes , Catequina , Persea , Proantocianidinas , Persea/química , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/síntesis química , Proantocianidinas/química , Proantocianidinas/farmacología , Proantocianidinas/síntesis química , Proantocianidinas/aislamiento & purificación , Catequina/química , Catequina/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Pruebas de Sensibilidad Microbiana , Antiinfecciosos/farmacología , Antiinfecciosos/química , Antiinfecciosos/síntesis química , Compuestos de Sulfhidrilo/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Antibacterianos/aislamiento & purificación , Fenoles/química , Fenoles/farmacología , Fenoles/aislamiento & purificación , Fenoles/síntesis química

RESUMEN

Polyporoid fungi represent a vast source of bioactive compounds with potential pharmacological applications. The importance of polyporoid fungi in traditional Chinese medicine has led to an extensive use of some species of Ganoderma for promoting health and longevity because their consumption is associated with several bioactivities. Nevertheless, bioactivity of some other members of the Polyporaceae family has also been reported. This work reports the antiproliferative and antibacterial activity of crude extracts obtained from fruiting bodies of polypore fungi collected from the central region of Veracruz, Mexico, aimed at understanding the diversity of polypore species with potential pharmacological applications. 29 collections were identified macro- and microscopically in 19 species of polyporoid fungi, belonging to 13 genera. The antiproliferative activity screening of extracts against solid tumor cell lines (A549, SW1573, HeLa, HBL-100, T-47D, WiDr) allow us to identify four extracts with strong bioactivity [half-maximal growth inhibition (GI50) ≤ 50 µg/mL]. After this, a phylogenetic analysis of DNA sequences from the ITS region obtained from bioactive specimens allowed us to identify three extracts as Pycnoporus sanguineus (GI50 = ≤ 10 µg/mL) and the fourth bioactive extract as Ganoderma oerstedii (GI50 = < 50 µg/mL. Likewise, extracts from P. sanguineus showed mild or moderate antibacterial activity against Escherichia coli, Staphylococcus aureus and Xanthomonas albilineas. Bioprospecting studies of polyporoid fungi add to the knowledge of the diversity of macrofungi in Mexico and allow us to select one of the bioactive P. sanguineus to continue the pursuit of bioactive compounds through mycochemical studies.

Asunto(s)

Antibacterianos , Filogenia , México , Humanos , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/química , Polyporaceae/química , Polyporaceae/clasificación , Cuerpos Fructíferos de los Hongos/química , Pruebas de Sensibilidad Microbiana

RESUMEN

Rhizophora extracts have several potential biological activities, and their metabolites can be used in the pharmaceutical industry. Extracts of Rhizophora species obtained from mangroves have shown prospective activity against Staphylococcus aureus. This study aimed to investigate the chemical profile of Rhizophora mangle leaves from fringe, basin, and transition mangrove zones and their bactericidal/bacteriostatic potential against S. aureus. R. mangle leaves were collected monthly in 2018 from litterfall in three different zones of the mangrove of Guaratiba State Reserve: fringe, basin, and transition. Extracts were prepared from the material collected in October and December for LC-HRMS/MS analysis, and dereplication was performed using a molecular library search and the classical molecular networking GNPS platform. The minimum inhibitory concentrations (MICs) of the aqueous extract of R. mangle against S. aureus were determined. No S. aureus growth was observed compared to the control for extracts collected from September to December. Different compounds were annotated in each region, yet a marked presence of phenolic compounds was noted, among them glycosylated flavonoid derivatives of quercetin and kaempferol. The results suggest bactericidal/bacteriostatic activity for extracts of R. mangle leaves collected in 2018 from three mangrove forest zones.

Asunto(s)

Antibacterianos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Hojas de la Planta , Rhizophoraceae , Staphylococcus aureus , Rhizophoraceae/química , Rhizophoraceae/microbiología , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Extractos Vegetales/farmacología , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química

RESUMEN

The new flavonoid (-)-4'-O-methylepicatechin 5-O-ß-D-glucopyranoside (1), along with four known triterpenes (2-5), a steroid (6), and a flavonoid (7) were isolated from the ethyl acetate extract of Maytenus quadrangulata leaves. The chemical structures of the isolated compounds were determined through analysis of 1D NMR (1H and 13C) spectroscopic data, in addition to 2D NMR and spectrometric (MS) data for compound 1. This is the first report of the isolation of daucosterol (6) and (-)-4'-O-methylepigallocatechin (7) from this species. Compounds 1 and 7 were evaluated against the bacteria Staphylococcus aureus and Klebsiella pneumoniae, but neither exhibited activity even at the highest concentration tested.

Asunto(s)

Acetatos , Antibacterianos , Flavonoides , Klebsiella pneumoniae , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Hojas de la Planta , Staphylococcus aureus , Triterpenos , Hojas de la Planta/química , Triterpenos/química , Triterpenos/aislamiento & purificación , Triterpenos/farmacología , Flavonoides/aislamiento & purificación , Flavonoides/química , Flavonoides/farmacología , Staphylococcus aureus/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Klebsiella pneumoniae/efectos de los fármacos , Acetatos/química , Antibacterianos/farmacología , Antibacterianos/aislamiento & purificación , Antibacterianos/química , Maytenus/química , Estructura Molecular

RESUMEN

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

Asunto(s)

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

RESUMEN

To evaluate the antibacterial, antibiofilm and antivirulence potential of the main diterpenes from Copaifera spp. oleoresins against multidrug-resistant (MDR) bacteria. Antimicrobial assays included determination of the Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC), Minimum Inhibitory Concentration of Biofilm (MICB50), as well as synergistic and antivirulence assays for eight diterpenes against MDR. The tests revealed that two diterpenes (named 1 and 5) showed the best results, with MIC and MBC between 12.5 and 50 µg/mL against most MDR bacteria. These diterpenes exhibited promising MICB50 in concentration between 3.12-25 µg/mL but showed no synergistic antimicrobial activity. In the assessment of antivirulence activity, diterpenes 1 and 5 inhibited only one of the virulence factors evaluated (Dnase) produced by some strains of S. aureus at subinhibitory concentration (6.25 µg/mL). Results obtained indicated that diterpenes isolated from Copaifera oleoresin plays an important part in the search of new antibacterial and antibiofilm agents that can act against MDR bacteria.

Asunto(s)

Antibacterianos , Biopelículas , Diterpenos , Farmacorresistencia Bacteriana Múltiple , Fabaceae , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Biopelículas/efectos de los fármacos , Diterpenos/farmacología , Diterpenos/aislamiento & purificación , Antibacterianos/farmacología , Antibacterianos/aislamiento & purificación , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Fabaceae/química , Extractos Vegetales/farmacología , Extractos Vegetales/aislamiento & purificación , Virulencia/efectos de los fármacos

RESUMEN

In this study, we purified a lectin isolated from the seeds of Dioclea bicolor (DBL) via affinity purification. Electrophoresis analysis revealed that DBL had three bands, α, ß, and γ chains, with molecular masses of approximately 29, 14, and 12 kDa, respectively. Gel filtration chromatography revealed that the native form of DBL had a molecular mass of approximately 100 kDa, indicating that it is a tetramer. Interestingly, DBL-induced hemagglutination was inhibited by several glucosides, mannosides, ampicillin, and tetracycline with minimum inhibitory concentration (MIC) values of 1.56-50 mM. Analysis of the complete amino acid sequence of DBL revealed the presence of 237 amino acids with high similarity to other Diocleinae lectins. Circular dichroism showed the prominent ß-sheet secondary structure of DBL. Furthermore, DBL structure prediction revealed a Discrete Optimized Protein Energy (DOPE) score of -26,642.69141/Normalized DOPE score of -1.84041. The DBL monomer was found to consist a ß-sandwich based on its 3D structure. Molecular docking showed the interactions between DBL and α-D-glucose, N-acetyl-D-glucosamine, α-D-mannose, α-methyl-D-mannoside, ampicillin, and tetracycline. In addition, DBL showed antimicrobial activity with an MIC of 125 µg/mL and exerted synergistic effects in combination with ampicillin and tetracycline (fractional inhibitory concentration index ≤ 0.5). Additionally, DBL significantly inhibited biofilm formation and showed no toxicity in murine fibroblasts (p < 0.05). These results suggest that DBL exhibits antimicrobial activity and works synergistically with antibiotics.

Asunto(s)

Antibacterianos , Dioclea , Lectinas de Plantas , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Ratones , Animales , Lectinas de Plantas/química , Lectinas de Plantas/farmacología , Lectinas de Plantas/aislamiento & purificación , Dioclea/química , Simulación del Acoplamiento Molecular , Pruebas de Sensibilidad Microbiana , Ampicilina/farmacología , Ampicilina/química

RESUMEN

Geopropolis resins are produced by stingless bees (Meliponinae), developed from the collection of resinous materials, waxes and exudates, from the flora of the region where stingless bees are present, in addition to the addition of clay or earth in its composition. Several biological activities are attributed to Ethanol Extracts of Geopropolis (EEGP). The bioactive properties are associated with the complex chemical composition that the samples have. This work aims to evaluate the biological activities of the EEGP, in order to contribute with a natural therapeutic alternative, to face infections, mainly those caused by resistant strains of Staphylococcus aureus. The EEGP MIC tests showed antibacterial activity against two strains of S. aureus, both at concentrations of 550 µg/mL. The MBC performed with the inhibition values showed that the EEGP has bacteriostatic activity in both strains. Biofilm inhibition rates exhibited an average value greater than 65 % at the highest concentration. The EEGP antioxidant potential test showed good antioxidant activity (IC50) of 11.05±1.55 µg/mL. In the cytotoxicity test against HaCat cells, after 24 hours, EEGP induced cell viability at the three tested concentrations (550 µg/mL: 81.68±3.79 %; 1100 µg/mL: 67.10±3.76 %; 2200 µg/mL: 67.40±1.86 %). In view of the above, the safe use of EEGP from the brazilian northeast could be proven by the cytotoxicity test, and its use as an antioxidant and antibacterial agent has proven to be effective, as an alternative in combating oxidative stress and microorganisms such as S. aureus, which, through the spread and ongoing evolution of drug resistance, generates an active search for effective solutions.

Asunto(s)

Antibacterianos , Biopelículas , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus , Staphylococcus aureus/efectos de los fármacos , Animales , Abejas , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Humanos , Biopelículas/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Própolis/química , Própolis/farmacología , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Relación Dosis-Respuesta a Droga

RESUMEN

This study explores the potential of propolis, a resinous substance produced by bees, from Melipona rufiventris species. With its composition encompassing resin, wax, pollen, and soil, propolis holds historical significance in traditional medicine within tropical regions. This research is driven by the scarcity of information surrounding M. rufiventris propolis, prompting an investigation into its chemical constituents, in vivo toxicity, and antimicrobial, antioxidant, and anti-inflammatory properties. This exploration could potentially uncover novel applications for this natural product, bolstering both meliponiculture practices and the preservation of native bee populations. The propolis was sampled in Cabo Verde-MG and underwent ethanolic extraction to yield an extract (EEP) for analysis. Chemical assessments (Folin-Ciocalteau, and UHPLC-HRMS) revealed the presence of polyphenols, including flavonoids. The EEP demonstrated higher antimicrobial activity against Gram-positive bacteria and exhibited efficacy against multiresistant strains isolated from complex wounds. Synergistic interactions with commercial antibiotics were also observed. Furthermore, anti-inflammatory evaluations showcased the EEP's potential in reducing NF-kB activation and TNF-α release at non-toxic concentrations. Despite these promising biological activities, the EEP exhibited no antiproliferative effects and demonstrated safety in both the MTS assay and the G. mellonella model. Collectively, these findings highlight the M. rufiventris propolis extract as a valuable reservoir of bioactive compounds with multifaceted potential.

Asunto(s)

Antiinflamatorios , Antioxidantes , Pruebas de Sensibilidad Microbiana , Própolis , Própolis/química , Própolis/farmacología , Animales , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Abejas , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Bacterias Grampositivas/efectos de los fármacos , Antiinfecciosos/farmacología , Antiinfecciosos/química , Antiinfecciosos/aislamiento & purificación , Ratones , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación

RESUMEN

The crude acetone extract of a marine Micromonospora sp. strain associated with Eudistoma vannnamei was fractioned with hexane and ethyl acetate. The crude extract and both soluble fractions were assayed against several bacteria strains. The new polycyclic quinones 12-hydroxy-9-propyltetracene-6,1-dione (1), 5,12-dihydroxy-4-methoxy-9-propyltetracene-5,12-dione (2), and 4,6-dihydroxy-3-methoxycarbonyl- methyl-6a-(oxobutyl)-5,12-anthraquinone (3), along with the known 4,6-dihydroxy-3-methoxycarbonyl-methyl-6a-(oxo-3-methyl-butyl)-5,12-anthraquinone (4) and 4,6-dihydroxy-3-methoxycarbonyl-methyl-6a-(oxopentyl)-5,12-anthraquinone (5) were isolated from the hexane-soluble fraction, while from the active ethyl acetate fraction were isolated the known 4,6,11-trihydroxy-9-propyltetracene-5,12-dione (6), 4-methoxy-9-propyltetracene-6,11-dione (7), 7,8,9,10-tetrahydro-9-hydroxy-4-methoxy-9-propyltetracene-6,11-dione (8), and 10ß-carbomethoxy-7,8,9,10-tetrahydro-4,6,7α,9α,11-pentahydroxy-9-propyltetracene-5,12-dione (9). The structures of the new compounds were established by interpretation of HRMS and NMR techniques. A study of molecular docking was performed with the compounds from the active ethyl acetate fraction to correlate tentatively with the antimicrobial activity. Molecular docking, RMSD, RMSF, and MM-GBSA evaluations were performed to investigate the inhibitory activity of 6-8 against the protein PDB-codex 1MWT, being considered a promising target for studying drug development responsible for inhibiting replication of Staphylococcus aureus. Penicillin G was used as the standard inhibitory. Anthracyclinones 6-8 were the best hydrolase inhibitor with affinity energy -8.1 to -7.9 kcal/mol compared to penicillin G, which presented -6.9 kcal/mol. Both 8 and 7 present potent inhibitory effects against hydrolase through molecular dynamics simulation and exhibit favorable drug-like properties, promising new hydrolase blockers to fight bacterial infections from Staphylococcus aureus.

Asunto(s)

Antibacterianos , Pruebas de Sensibilidad Microbiana , Micromonospora , Simulación del Acoplamiento Molecular , Quinonas , Micromonospora/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Quinonas/química , Quinonas/farmacología , Quinonas/aislamiento & purificación , Estructura Molecular , Compuestos Policíclicos/farmacología , Compuestos Policíclicos/química , Compuestos Policíclicos/aislamiento & purificación

RESUMEN

Cats are susceptible to S. aureus, which mainly colonizes the nose and ears of these feline species. Otitis externa in cat ears is one of the illnesses produced by S. aureus in animals. Antibiotic therapy for affected animals is the conventional treatment for infections by S. aureus. Antibiotic use during prolonged treatment and given at the wrong doses can cause germs to become resistant. Given this context, research on S. aureus isolated from cat ears and tests for antibiotic resistance and the mecA gene is required. Samples of cat ears were obtained from the Amies media using a sterile cotton swab. Bacterial isolation was done on MSA media, and then the catalase and coagulase assays were used to identify the bacteria. S. aureus isolates were evaluated for sensitivity using disks of the antibiotics cefoxitin, tetracycline, erythromycin, gentamicin, and chloramphenicol connected to MHA media. All positive isolates of S. aureus underwent MRSA testing, and then the mecA gene was detected. The sample investigation revealed that 91% (91/100) were positive for S. aureus, and 3.30% (3/91) were confirmed to be multidrug-resistant (MDR) because they are resistant to 3­4 antibiotic classes. Out of the 12 MRSA isolates analyzed, the mecA gene was detected in one isolate. Inappropriate antibiotic use causes bacterial resistance in pets. Additionally, excessive antibiotic use in a population might develop acquired bacterial resistance to an antibiotic. Antibiotic use in animals must be assessed to administer medication and prevent the development of antibiotic resistance appropriately.(AU)

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Gatos são suscetíveis a adquirir S.aureus que colonizam principalmente as narinas e os ouvidos de espécies de felinos. A otite externa no ouvido dos gatos é uma das doenças produzidas pelo S.aureus nos animais. A terapia com antibióticos é o tratamento convencional para as infecções produzidas pelo S.aureus. Os antibióticos utilizados durante o prolongado tratamento e o emprego de sub doses podem selecionar microorganismos resistentes. Com base em tais argumentos torna-se necessária a pesquisa de S.aureus isolados do ouvido dos gatos, bem como, a realização de testes para a resistência a antibióticos e do gene mecA. Empregando swabs estéreis de algodão foram obtidas amostras dos ouvidos dos gatos em meio de Amies. O isolamento bacteriano foi efetuado em meio MAS e os testes catalase e coagulase foram realizados para a identificação das bactérias. A sensibilidade dos isolados de S.aureus foi avaliada com o emprego de discos dos antibióticos cefoxitin, tetraxiclina, eritromicina, gentamicina e cloranfenicol, incorporados no meio MHA. Todos os isolados positivos de S.aureus foram submetidos ao test MRSA para a detecção do gene mecA. A amostra investigada revelou 91% (91/100) de positivos para S.aureus, dos quais, 3,30% (3/91) foram resistentes a múltiplas drogas (MDR) pois foram resistentes a 3-4 classes de antibióticos. De 12 MRSA isolados analisados o gene mecA foi detectado em um isolado. O uso inapropriado de antibióticos é a causa da resistência bacteriana em pets. Adicionalmente o emprego excessivo de antibióticos em uma população pode resultar no desenvolvimento de resistência bacteriana adquirida a antibióticos. O uso de antibióticos em animais deve ser ordenado por uma administração de medicamentos apropriada para prevenir o desenvolvimento da resistência.(AU)

Asunto(s)

Animales , Infecciones Estafilocócicas/inmunología , Gatos/microbiología , Farmacorresistencia Fúngica/genética , Staphylococcus aureus/aislamiento & purificación , Genes Bacterianos , Indonesia , Antibacterianos/aislamiento & purificación

RESUMEN

Polysaccharides are macromolecules with important inherent properties and potential biotechnological applications. These complex carbohydrates exist throughout nature, especially in plants, from which they can be obtained with high yields. Different extraction and purification methods may affect the structure of polysaccharides and, due to the close relationship between structure and function, modify their biological activities. One of the possible applications of these polysaccharides is acting on the skin, which is the largest organ in the human body and can be aged by intrinsic and extrinsic processes. Skincare has been gaining worldwide attention not only to prevent diseases but also to promote rejuvenation in aesthetic treatments. In this review, we discussed the polysaccharides obtained from plants and their innovative potential for skin applications, for example as wound-healing, antimicrobial, antioxidant and anti-inflammatory, antitumoral, and anti-aging compounds.

Asunto(s)

Antibacterianos/farmacología , Antiinflamatorios/farmacología , Antineoplásicos/farmacología , Antioxidantes/farmacología , Neoplasias/tratamiento farmacológico , Polisacáridos/farmacología , Envejecimiento/efectos de los fármacos , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Bacterias/efectos de los fármacos , Humanos , Plantas Medicinales/química , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Cuidados de la Piel , Cicatrización de Heridas/efectos de los fármacos

RESUMEN

Bacteria can produce nitrogenous compounds via both primary and secondary metabolic processes. Many bacterial volatile nitrogenous compounds produced during the secondary metabolism have been identified and reported for their antioxidant, antibacterial, antifungal, algicidal and antitumor activities. The production of these nitrogenous compounds depends on several factors, including the composition of culture media, growth conditions, and even the organic solvent used for their extraction, thus requiring their identification in specific conditions. In this review, we describe the volatile nitrogenous compounds produced by bacteria especially focusing on their antimicrobial activity. We concentrate on azo-compounds mainly pyrazines and pyrrolo-pyridines reported for their activity against several microorganisms. Whenever significant, extraction and identification methods of these compounds are also mentioned and discussed. To the best of our knowledge, this is first review describing volatile nitrogenous compounds from bacteria focusing on their biological activity.

Asunto(s)

Antibacterianos/farmacología , Compuestos Azo/farmacología , Bacterias/efectos de los fármacos , Compuestos Orgánicos Volátiles/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Compuestos Azo/química , Compuestos Azo/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Compuestos Orgánicos Volátiles/química , Compuestos Orgánicos Volátiles/aislamiento & purificación