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1.
Chem Biodivers ; 20(2): e202201097, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36583710

RESUMEN

A new quinoline alkaloid, 5-hydroxy-6-methoxy-N-methyl-2-phenylquinoline-4-one (1), and seventeen known quinoline alkaloids (2-18) were isolated from the roots of Orixa japonica. The structure of 1 was determined by analysis of spectroscopic data. Among them, compounds 2, 3, and 13 were isolated from this plant for the first time. All isolates were screened for the anti-pathogenic fungi activities, including Rhizoctonia solani, Magnaporthe oryzae, and Phomopsis sp. The results showed that five compounds (4, 8, 10, 11, and 12) exhibited significant anti-pathogenic fungi effects at 50.0 µg/mL. In special, compound 10 exhibited the best antifungal activities toward R. solani and M. oryzae with the IC50 values of 37.86 and 44.72 µM, respectively, better than that of the positive control, hymexazol (IC50 121.21 and 1518.18 µM, respectively). Moreover, eleven new quinoline alkaloids derivatives (12a-12k) were designed and synthesized to investigate the structure-activity relationships (SARs). The SARs analysis indicated that the furo[2,3-b]quinoline skeleton and the methoxy at C-7 (compounds 8, 11, and 12) played a key role for improving the antifungal activities.


Asunto(s)
Alcaloides , Quinolinas , Antifúngicos/farmacología , Estructura Molecular , Relación Estructura-Actividad , Quinolinas/química , Hongos
2.
Molecules ; 28(2)2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36677921

RESUMEN

It has now been proven that many pathogens that cause infections and inflammation gradually mutate and become resistant to antibiotics. Chemically synthesized drugs treating inflammation most often only affect symptoms, but side effects could lead to the failure of human organs' functionality. On the other hand, plant-derived natural compounds have a long-term healing effect. It was shown that sea buckthorn (SBT) twigs are a rich source of biologically active compounds, including oligomeric proanthocyanidins (PACs). This study aimed to assess the anti-pathogenic and anti-inflammatory activity of water/ethanol extracts and PACs obtained from the lignocellulosic biomass of eight SBT cultivars. The anti-pathogenic activity of extracts and PACs was studied against pathogenic bacteria Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Bacillus cereus and fungus Candida albicans in 96-well plates by the two-fold serial broth microdilution method. The anti-bacterial activity of purified PACs was 4 and 10 times higher than for water and water/ethanol extracts, respectively, but the extracts had higher anti-fungal activity. Purified PACs showed the ability to reduce IL-8 and IL-6 secretion from poly-I:C-stimulated peripheral blood mononuclear cells. For the extracts and PACs of SBT cultivar 'Maria Bruvele' in the concentration range 0.0313-4.0 mg/mL, no toxic effect was observed.


Asunto(s)
Proantocianidinas , Humanos , Proantocianidinas/farmacología , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Leucocitos Mononucleares , Bacterias , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antioxidantes/farmacología , Etanol/farmacología , Agua/farmacología , Antiinflamatorios/farmacología , Inflamación/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana
3.
Microb Pathog ; 173(Pt A): 105857, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36397614

RESUMEN

OBJECTIVE: We investigated the anti-inflammatory and anti-pathogenic activities of Lacticaseibacillus rhamnosus IDCC 3201 isolated from the feces of breast-fed infants. METHODS: Cell viability, nitric oxide (NO) production, and expression of inflammatory markers by L. rhamnosus IDCC 3201 were quantitatively analyzed in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. The antibacterial and antifungal activities of L. rhamnosus IDCC 3201 against various pathogens were also investigated. RESULTS: Treatment of LPS-induced macrophages with cell-free supernatant of L. rhamnosus IDCC 3201 significantly decreased the expression levels of tumor necrosis factor (TNF-α) and interleukin-6 (IL-6). Nitric oxide synthase (iNOS) and cyclooxygenase (COX-2) levels also significantly decreased in LPS-induced macrophages. Phenotypically, the treatment of L. rhamnosus IDCC 3201 reduced the production of nitric oxide (NO) in LPS-induced macrophages. Furthermore, L. rhamnosus IDCC 3201 was proven to have potent inhibitory activities against various pathogens responsible for inflammatory responses in the gastrointestinal tract (i.e., Bacillus cereus, Enterococcus faecalis, Staphylococcus aureus, and Salmonella Typhimurium), respiratory system (i.e., Streptococcus pneumoniae), and vagina (i.e., Candida albicans). CONCLUSION: L. rhamnosus IDCC 3201 has anti-inflammatory activity in terms of decreased expression of cytokines, inflammation-inducible enzymes in LPS-induced macrophages, and anti-pathogenic activity.


Asunto(s)
Lacticaseibacillus rhamnosus , Lipopolisacáridos , Lactante , Femenino , Humanos , Óxido Nítrico , Heces , Antiinflamatorios/farmacología , Factor de Necrosis Tumoral alfa
4.
Fish Shellfish Immunol ; 126: 73-83, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35609759

RESUMEN

The increasing demand for fish consumption has promoted the rapid development of fish aquaculture. With the continuous expansion of culture scale and the deterioration of culture environment, various diseases have broken out frequently, leading to huge economic losses to fish farming. Antibiotics and chemicals are common options to prevent and control of fish diseases, but their use is now restricted or even banned due to serious problems such as drug residues, pathogen resistance, and environmental pollution. Herbs and their extracts have increasingly become promising supplements and alternatives, because of their effectiveness, safety, environmental friendliness and less drug resistance. The application of herbal medicines in prevention and control of fish diseases is mainly attributed to the powerful immune enhancement, antioxidation or direct anti-pathogenic efficacies of their effective components, including mainly polyphenols, polysaccharides, saponins, flavonoids, alkaloids, and essential oils. Recently these herbal active ingredients have been extensively studied for their efficacies in prevention and control of viral, bacterial, parasitic, and fungal diseases in fish. In the present paper, we comprehensively summarize the research progress of the active ingredients of herbal medicines used for prevention and control of fish diseases, especially of their action mechanisms, and highlight the potential application of the herbal medicines in fish aquaculture.


Asunto(s)
Alcaloides , Medicamentos Herbarios Chinos , Enfermedades de los Peces , Plantas Medicinales , Animales , Acuicultura , Enfermedades de los Peces/prevención & control , Peces
5.
Biochem Soc Trans ; 49(2): 617-627, 2021 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-33704415

RESUMEN

The human skin microbiota forms a key barrier against skin pathogens and is important in modulating immune responses. Recent studies identify lactobacilli as endogenous inhabitants of healthy skin, while inflammatory skin conditions are often associated with a disturbed skin microbiome. Consequently, lactobacilli-based probiotics are explored as a novel treatment of inflammatory skin conditions through their topical skin application. This review focuses on the potential beneficial role of lactobacilli (family Lactobacillaceae) in the skin habitat, where they can exert multifactorial local mechanisms of action against pathogens and inflammation. On one hand, lactobacilli have been shown to directly compete with skin pathogens through adhesion inhibition, production of antimicrobial metabolites, and by influencing pathogen metabolism. The competitive anti-pathogenic action of lactobacilli has already been described mechanistically for common different skin pathogens, such as Staphylococcus aureus, Cutibacterium acnes, and Candida albicans. On the other hand, lactobacilli also have an immunomodulatory capacity associated with a reduction in excessive skin inflammation. Their influence on the immune system is mediated by bacterial metabolites and cell wall-associated or excreted microbe-associated molecular patterns (MAMPs). In addition, lactobacilli can also enhance the skin barrier function, which is often disrupted as a result of infection or in inflammatory skin diseases. Some clinical trials have already translated these mechanistic insights into beneficial clinical outcomes, showing that topically applied lactobacilli can temporarily colonize the skin and promote skin health, but more and larger clinical trials are required to generate in vivo mechanistic insights and in-depth skin microbiome analysis.


Asunto(s)
Antibiosis/inmunología , Candida albicans/inmunología , Inflamación/inmunología , Lactobacillus/inmunología , Piel/inmunología , Staphylococcus aureus/inmunología , Antibiosis/fisiología , Adhesión Bacteriana/inmunología , Bacteriocinas/inmunología , Bacteriocinas/metabolismo , Candida albicans/fisiología , Humanos , Sistema Inmunológico/inmunología , Sistema Inmunológico/microbiología , Inflamación/microbiología , Lactobacillus/metabolismo , Lactobacillus/fisiología , Piel/microbiología , Piel/patología , Staphylococcus aureus/fisiología
6.
Microb Pathog ; 158: 105062, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34186116

RESUMEN

One of the major factors that affect the total production of fisheries is the declining number of catches and aquaculture production due to the high pathogenicity in aquatic environment. This enforces the need to find anti-pathogenic agents that could solve the problem. In addition, the application of potential Bacillus cereus SN7 and Vagococcus fluvialis CT21 isolated and identified from the sea water of Siak, Riau, Indonesia need to be optimally exploited. The aim of this study, therefore, is to determine the component of bioactive compounds present in Bacillus cereus SN7 and Vagococcus fluvialis CT21, and also to explore their intrinsic potential as a biological control agent in fisheries, especially for inhibiting the growth of pathogenic bacteria (Vibrio alginolyticus, Aeromonas hydrophila and Pseudomonas aeruginosa). The method used was experimental, where the ethyl acetate crude extracts of both samples were analyzed for their phytochemical content, followed by thin layer chromatography analysis and Liquid Chromatography Mass Spectrometry. In addition, anti-pathogenic activity test was performed using the Kirby-Bauer method, minimum inhibitory and bactericidal concentration analysis. The results showed alkaloids, flavonoids, and saponins were the potential bioactive components in the crude extracts of Bacillus cereus SN7 and Vagococcus fluvialis CT21. Furthermore, the anti-pathogenic activity test demonstrated the ability for both bacteria to inhibit three types of pathogens with the following inhibitory zone values: Vibrio alginolyticus (10-11 mm), Aeromonas hydrophila (8-12 mm), and Pseudomonas aeruginosa (8-10 mm). In conclusion secondary metabolite compounds produced by Bacillus cereus SN7 and Vagococcus fluvialis CT21 possess the capacity to inhibit pathogenic bacteria. Hence, both samples are potential candidates for anti-pathogen development, especially in fisheries.


Asunto(s)
Bacillus cereus , Enterococcaceae , Animales , Antibacterianos/farmacología , Peces , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa
7.
Prep Biochem Biotechnol ; 49(2): 176-183, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30688152

RESUMEN

The present investigation was aimed to determine the anti-pathogenic, antibiofilm, and technological properties of fermented food associated Staphylococcus succinus strain AAS2. The anti-pathogenic attribute of cell-free neutralized supernatant (CFNS) of strain AAS2 was assessed against food-borne and enteric pathogens that revealed promising activity against Staphylococcus aureus and Enterobacter aerogenes with high arbitrary unit of 220.25 ± 3.3 and 170.2 ± 4.6 AU/mL, respectively. Furthermore, the antibiofilm and time-kill assay of CFNS of strain AAS2 depicted remarkable reduction in biofilm formation of indicator pathogens in a dose-dependent manner. Moreover, time-kill assay data revealed the drastic reduction in the viability (log cfu/mL) of S. aureus and E. aerogenes in the presence of varied minimum inhibitory concentration ranges of CFNS. The distinct technological properties of strain AAS2 were demonstrated using standard methodologies. Reported results estimated moderate level of exopolysaccharide (41.3 ± 0.6 mg/L) and lipase production (8.3 ± 0.3 mm), followed by remarkable autolytic (30.1 ± 1.2-43.1 ± 1.3%), catalase (13.82 ± 0.3 AU), and nitrate reductase (10.25 ± 0.3 mM nitrite/mg dry weight) activities under standard conditions. Most importantly, the strain cleared the specific in vitro safety assessment tests. The described anti-pathogenic and technological traits of strain AAS2 paved the way to utilize it in pharmaceutical as well as food processing industries as starter/adjunct culture.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Enterobacter aerogenes/efectos de los fármacos , Alimentos Fermentados/microbiología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus/química , Enterobacter aerogenes/fisiología , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Humanos , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/fisiología
8.
Microb Pathog ; 125: 318-324, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30278209

RESUMEN

Silver ions, because of its recognised antimicrobial activity are reported in several regions for the very long time while ergosterol, apart from its role as a secondary metabolite, structural component of the fungal cell membranes, also turns out to be activating defence response in plants. Silver ions biosynthesized by terpene ergosterol producing Trichoderma harzianum could be used against other plant pathogenic fungi. In this work, possible interaction of the silver ions with ergosterol enzyme has been investigated using a computational approach. Protein model construction via prior knowledge of sequences and molecular ligand docking experiments as well as structural and sequence comparisons were executed to identify potential active-site in ergosterol enzyme. Moldock score of -48.5747 with the reranking score of -40.0228 has been reported by Molegro Virtual Docker(MVD) at ergosterol enzyme's active site positions for silver ion. Apart from the core of the active site, four other positions have been occupied by silver ion. The interacting site surrounded by Cys339, Arg343, Lue365, Leu336 and Trp371 formed hydrophobic bonds with silver. The anti-microbial activity against phytopathogens is believed to increase synergistically when combined with ergosterol enzyme. Thus the computational analysis of silver ion in conjugation with ergosterol enzyme provided additional strategies to improve the ability of the Trichoderma strains in biocontrol of pathogenic fungi. In the present study, silver ion based formulations which are produced by strong bio-control fungi as shown were estimated in response to different plant pathogen in further studies.


Asunto(s)
Enzimas/metabolismo , Ergosterol/metabolismo , Nanopartículas/metabolismo , Plata/metabolismo , Trichoderma/metabolismo , Sitios de Unión , Simulación del Acoplamiento Molecular , Unión Proteica
9.
Lett Appl Microbiol ; 67(6): 579-588, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30203855

RESUMEN

This study focused on the evaluation of fungal compound for their anti-pathogenic potential against respiratory pathogens. Soil samples were collected from various geographical regions in Madurai, fungal strain was isolated and identified as Aspergillus terreusDMTMGK004 (MGK004). Secondary metabolites were extracted and evaluated for antioxidant potential. It exhibited significantly high anti-proliferative property against gastric adenocarcinoma (AGS) cell lines. Antimicrobial activity against Gram positive (Streptococcus pneumoniae) and Gram negative (Klebsiella pneumoniae and Haemophilus influenzae) respiratory pathogens were analysed and the minimum inhibitory concentration (MIC) values were determined. Furthermore, the time-killing assay illustrated that the metabolite eliminates 50% of the vegetative cells within few hours of the treatment. From the spectral data, the major functional groups present in the compound were determined as carbonyl group and phenolic hydroxyl group which contribute towards its bioactivity. The compound significantly depreciates the production of extracellular polysaccharides which results in the weakening of biofilm architecture and resistance towards serum killing and phagocytosis. It also induced cell membrane damage which leads to protein and nucleic acid leakage. Hence, the results of the present study could provide a better insinuation towards the formulation of new drug targeting respiratory pathogens. SIGNIFICANCE AND IMPACT OF THE STUDY: The ubiquitous fungi Aspergillus terreus is well known for its secondary metabolite production. The fungus was evaluated for production of antagonistic molecule to reduce the growth of infectious agents causing respiratory infections. It exhibited the biological means of antioxidant, anti-proliferative and anti-pathogenic compound production. The compound exhibits killing effect against respiratory pathogens within two hours. It induced cell membrane damage leading to protein and nucleic acid leakage. It significantly reduced the production of extracellular polysaccharides. The results provide needed information to design innovative strategies for targeting pathogenic factors of the respiratory pathogens instead of killing it precisely.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Aspergillus/metabolismo , Haemophilus influenzae/efectos de los fármacos , Klebsiella pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/efectos de los fármacos , Aspergillus/aislamiento & purificación , Membrana Celular/efectos de los fármacos , Humanos , India , Pruebas de Sensibilidad Microbiana , Estrés Oxidativo/efectos de los fármacos , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones del Sistema Respiratorio/microbiología , Microbiología del Suelo , Virulencia
10.
Foods ; 13(14)2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39063385

RESUMEN

Probiotics restore gut microbial balance, thereby providing health-promoting effects to the host. They have long been suggested for managing intestinal disorders caused by pathogens and for improving gut health. This study evaluated the probiotic properties and anti-pathogenic effects of specific probiotic strains against the intestinal pathogens Staphylococcus aureus and Escherichia coli. The tested strains-Lactiplantibacillus plantarum LC27, Limosilactobacillus reuteri NK33, Lacticaseibacillus rhamnosus NK210, Bifidobacterium longum NK46, and Bifidobacterium bifidum NK175-were able to survive harsh conditions simulating gastric and intestinal fluids. These strains exhibited good auto-aggregation abilities (41.8-92.3%) and ideal hydrophobicity (30.9-85.6% and 38.3-96.1% for xylene and chloroform, respectively), along with the ability to co-aggregate with S. aureus (40.6-68.2%) and E. coli (38.6-75.2%), indicating significant adhesion levels to Caco-2 cells. Furthermore, these strains' cell-free supernatants (CFSs) demonstrated antimicrobial and antibiofilm activity against S. aureus and E. coli. Additionally, these strains inhibited gas production by E. coli through fermentative activity. These findings suggest that the strains tested in this study have potential as novel probiotics to enhance gut health.

11.
Int J Biol Macromol ; 253(Pt 4): 126856, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37714231

RESUMEN

This research aimed to prepare, characterize, and investigate the biological efficacy of chitosan­cobalt (II) oxide hybrid nanocomposites against a variety of micrograms. Analytical methods, FTIR, SEM, XRD, and EDX, were utilized to thoroughly characterize the produced CS-CoO nanocomposite. In FTIR spectra, the presence of the chitosan peaks in addition to that of CoO at 681 and 558 cm-1 confirmed that CoO molecules interact with the chitosan backbone. Moreover, in the XRD measurements, significantly less chitosan crystallinity was observed. Due to the incorporation of a larger amount of cobalt oxide within the polymer matrix. Applying the Debye-Sherrer calculation, the crystallite size was obviously reduced from 48.24 nm (5 wt %) to 19.27 nm (20 wt %) for the obtained nanocomposites. Furthermore, SEM measurements showed a transformation in the chitosan surface with the physical adsorption of CoO molecules on the surface active sites of chitosan that were visible in SEM graphs. Additionally, EDX determined the amount of Co element within the chitosan, with the sample of 20 wt % weight being found to be 19.26 wt %. The variable dose well-diffusion method was utilized to assess the efficacy of the CS-Co nanocomposite against a wide range of bacteria and fungi. CS - CoO nanocomposite is more effective than chitosan alone as an antibacterial agent against both Gram-positive and Gram-negative bacteria. Moreover, the MTT approach was employed to measure the cytotoxicity based on the cell viability of different cancer cell lines under different UV expositions. The proportion of the destroyed cells elevated due to the easy diffusion of CS - CoO nanocomposite into cancer cells as UV-free anticancer activity. UV exposition has stimulated the anticancer activity, which was attributed to an increase in ROS generation caused by the increased dose of the chitosan and its CS - CoO nanocomposites. Furthermore, the antioxidant capacities of the prepared nano-composites thin films were validated using the DPPH free radical scavenging method and showed good antioxidant activities with the DPPH radical compared with standard vitamin C. It has been noticed that by increasing the content of CoO nanoparticles from 5 to 20 wt %, the biological activity of the prepared nanocomposites was enhanced.


Asunto(s)
Quitosano , Nanocompuestos , Quitosano/farmacología , Quitosano/química , Antibacterianos/química , Antioxidantes , Bacterias Gramnegativas , Bacterias Grampositivas , Óxidos/farmacología , Cobalto , Nanocompuestos/química , Preparaciones Farmacéuticas
12.
Biomolecules ; 13(12)2023 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-38136611

RESUMEN

Previously, the protective role of the S-layer protein 2 (Slp2) of the vaginal Lactobacillus crispatus 2029 (LC2029) strain against foodborne pathogens Campylobacter jejuni, Salmonella enterica serovar Enteritidis, and Escherichia coli O157:H was demonstrated. We demonstrate the new roles of the Slp2-positive LC2029 strain and soluble Slp2 against C. albicans infections. We show that LC2029 bacteria can adhere to the surface of the cervical epithelial HeLa cells, prevent their contact with C. albicans, and block yeast transition to a pathogenic hyphal form. Surface-bound Slp2 provides the ability for LC2029 to co-aggregate with various C. albicans strains, including clinical isolates. C. albicans-induced necrotizing epithelial damage is reduced by colonization with the Slp2-positive LC2029 strain. Slp2 inhibits the adhesion of various strains of C. albicans to different human epithelial cells, blocks yeast transition to a pathogenic hyphal form, and prevents the colonization and pathogenic infiltration of mucosal barriers. Only Slp2 and LC2029 bacteria stimulate the production of protective human ß-defensin 3 in various epithelial cells. These findings support the anti-Candida albicans potential of the probiotic LC2029 strain and Slp2 and form the basis for further research on their ability to prevent and manage invasive Candida infections.


Asunto(s)
Candidiasis , Lactobacillus crispatus , Femenino , Humanos , Candida albicans , Células HeLa , Células Epiteliales/metabolismo
13.
J Oleo Sci ; 71(9): 1363-1374, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35965088

RESUMEN

Probiotics frontier in depressing the clinical bacterial pathogens to avoid multidrug resistance phenomenon. The present study aimed to determine the antibacterial efficiency of chitosan encapsulated probiotics isolated from buffalo milk samples against clinical bacterial pathogens. The Agar well method was used for antibacterial activity. Lactococcus lactis (A) and Lactobacillus curvattus (B) were isolated from fresh buffalo milk samples, identified via culturing media, Gram's staining, biochemical tests, and antibiogram analysis. Encapsulation of probiotics was carried out using chitosan and was characterized via a scanning electron microscope. Antibiogram analysis elicit that L. lactis culture (A1) was highly sensitive to chloramphenicol (17.66±0.47 mm), tobramycin (15.33±0.47 mm), and ciprofloxacin (12.33±0.47 mm) and resistant against tetracycline, Penicillin G, Erythromycin, Amoxycillin, Ceftriaxone, Cephalothin, and Cephradine, while L. curvattus culture (B1) was affected by Ceftriaxone (18.67±0.47 mm), Amoxycillin (14.33±0.94 mm), Cephalothin (13.67±0.47 mm), Erythromycin (13.33±0.47 mm), Penicillin G (12.67±0.47 mm), Cephradine (10.33±0.47 mm), and Chloramphenicol (9.67±0.47 mm) and resistant against tetracycline, Tobramycin, and Ciprofloxacin. Antibacterial efficacy of non-encapsulated probiotic cultures was significant and maximum inhibition of bacterial were recorded compared to their cellular components. SEM of encapsulated probiotics revealed that they were successfully covered with a chitosan protective layer and could be effective as bio-preservatives due to being slowly released at the target site. The current study concluded that L. lactis, L. curvattus, and their cellular components have a significant bactericidal effect against infectious pathogens and could be used as a potential therapeutic drug against infectious diseases.


Asunto(s)
Quitosano , Lactococcus lactis , Probióticos , Amoxicilina , Animales , Antibacterianos/farmacología , Búfalos , Ceftriaxona , Cefalotina , Cefradina , Quitosano/farmacología , Cloranfenicol , Ciprofloxacina , Eritromicina , Lactobacillus/fisiología , Lactococcus lactis/química , Lactococcus lactis/fisiología , Probióticos/farmacología , Tetraciclinas , Tobramicina
14.
Phytochemistry ; 201: 113251, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35644485

RESUMEN

Much of the plant lectin research was focused on these proteins from seeds, whereas lectins from other plant tissues have been less investigated. Although presence of lectins in the phloem exudate of Cucurbitaceae species was reported over 40 years ago, only a few proteins from this family have been purified and characterized with respect to ligand binding properties, primary and secondary structures, while no 3D structure of a member of this family is known so far. Unlike lectins from other plant families and sources (e.g., seeds and tubers), which exhibit specificity towards different carbohydrate structures, all the Cucurbitaceae phloem exudate lectins characterized so far have been shown to recognize only chitooligosaccharides or glycans containing chitooligosaccharides. Interestingly, some of these proteins also bind various types of RNAs, suggesting that they may also play a role in the transport of RNA information molecules in the phloem. The present review gives an overview of the current knowledge of Cucurbitaceae phloem exudate lectins with regard to their purification, determination of primary and secondary structures, elucidation of thermodynamics and kinetics of carbohydrate binding and computational modeling to get information on their 3D structures. Finally, future perspectives of research on this important class of proteins are considered.


Asunto(s)
Cucurbitaceae , Exudados y Transudados/metabolismo , Lectinas/análisis , Lectinas/metabolismo , Floema/metabolismo , Lectinas de Plantas/genética , Unión Proteica
15.
J Fungi (Basel) ; 8(1)2021 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-35049949

RESUMEN

Nine previously undescribed sesquiterpenoids, bipolarisorokins A-I (1-9); two new xanthones, bipolarithones A and B (10 and 11); two novel sativene-xanthone adducts, bipolarithones C and D (12 and 13); as well as five known compounds (14-18) were characterized from the kiwifruit-associated fungus Bipolaris sp. Their structures were elucidated by extensive spectroscopic methods, electronic circular dichroism (ECD), 13C NMR calculations, DP4+ probability analyses, and single crystal X-ray diffractions. Many compounds exhibited anti-pathogenic microorganism activity against the bacterium Pseudomonas syringae pv. actinidiae and four pathogenic microorganisms.

16.
In Vivo ; 35(1): 325-332, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33402481

RESUMEN

BACKGROUND: Salvia miltiorrhiza is a medical herb for human disorders including cardiovascular diseases and cancer. However, the interactions between Salvia miltiorrhiza and its endophytes are largely unknown. The current study aimed at identifying its endophytic fungi and examining their inhibitory effects on anti-pathogenic fungus. MATERIALS AND METHODS: Distinct species of endophytic fungi were isolated from the roots of Salvia miltiorrhiza, cultured, sequenced, aiming to predict their taxonomical structures. Meanwhile, extracts from each endophytic fungus fermentations were isolated, compared and evaluated on the inhibitory efficacies on five pathological fungi, Cercospora nicotianae, Phoma arachnidicola, Staphylococcus, Phytophthora eggplant, and Rhizoctonia cerealis. RESULTS: A total of 34 strains of endophytic fungi were obtained from Salvia miltiorrhiza. Among them, SX19 and C. Gloeosporioids exhibited the most effective inhibitions on five pathogenic fungi. CONCLUSION: The anti-fungal activities of the endophytic fungus from Salvia miltiorrhiza were confirmed for the first time, and this may benefit crop quality and production in the future.


Asunto(s)
Salvia miltiorrhiza , Basidiomycota , Endófitos/genética , Hongos , Humanos , Raíces de Plantas
17.
J Hazard Mater ; 408: 124896, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33387722

RESUMEN

Herein, we report the fabrication of highly oxidized silver oxide/silver/tin(IV) oxide (HOSBTO or Ag3+-enriched AgO/Ag/SnO2) nanocomposite under a robust oxidative environment created with the use of concentrated nitric acid. Tin(IV) hydroxide nanofluid is added to the reaction mixture as a stabilizer for the Ag3+-enriched silver oxide in the nanocomposite. The formation of Ag nanoparticles in this nanocomposite originates from the decomposition of silver oxides during calcination at 600 °C. For comparison, poorly oxidized silver oxide/silver/tin(IV) oxide (POSBTO with formula AgO/Ag/SnO2) nanocomposite has also been prepared by following the same synthetic procedures, except for the use of concentrated nitric acid. Finally, we studied in detail the anti-pathogenic capabilities of both nanocomposites against four hazardous pathogens, including pathogenic fish bacterium (Stenotrophomonas maltophilia stain EP10), oomycete (Phytophthora cactorum strain P-25), and two different strains of pathogenic strawberry fungus, BRSP08 and BRSP09 (Collectotrichum siamense). The bioassays reveal that the as-prepared HOSBTO and POSBTO nanocomposites exhibit significant inhibitory activities against the tested pathogenic bacterium, oomycete, and fungus in a dose-dependent manner. However, the degree of dose-dependent effectiveness of the two nanocomposites against each pathogen largely varies.


Asunto(s)
Nanopartículas del Metal , Nanocompuestos , Animales , Antibacterianos , Óxidos , Plata , Compuestos de Plata , Estaño
18.
Int J Antimicrob Agents ; 56(3): 106086, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32663508

RESUMEN

The adverse health effects of Staphylococcus aureus biofilm infections coupled with an increased global prevalence of antibiotic resistance highlight the need for novel anti-pathogenic, anti-biofilm compounds. The authors recently determined that ethyl-4-ethoxybenzoic acid (EEB) had anti-pathogenic, anti-biofilm activity. Based on this finding, a structure-activity analysis was undertaken to identify more effective compounds. Microtitre crystal violet assays followed by plate counts were conducted to measure the dose-dependent anti-biofilm and antimicrobial activities of 13 phenolic compounds related to EEB. By displaying these characteristics on a two-component plot, 4-ethoxybenzoic acid (4EB) and methyl gallate were identified as two anti-pathogenic, anti-biofilm compounds of interest. To characterize their mechanisms of activity, their effects on cell hydrophobicity, hemolysis activity, membrane integrity, extracellular polymeric substance production and vancomycin sensitivity were examined. Both 4EB and methyl gallate inhibited up to 87% of biofilm formation with minimal impact on the viability of stationary-phase cells or bacterial growth. Combination treatments of 4EB and vancomycin decreased the viability of biofilm-dwelling cells by up to 85% compared with vancomycin alone, indicating a synergistic effect. Methyl gallate did not potentiate vancomycin. 4EB decreased the percentage of hydrophobic cells in culture from 78% to 49%, indicating that 4EB may prevent biofilm formation by altering cell membrane hydrophobicity. These findings suggest that 4EB has potential as an anti-pathogenic, anti-biofilm agent for the prevention of S. aureus biofilms, or as a treatment for established biofilms when combined with antibiotics.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Éteres de Hidroxibenzoatos/farmacología , Staphylococcus aureus/efectos de los fármacos , Vancomicina/farmacología , Biopelículas/crecimiento & desarrollo , Sinergismo Farmacológico , Quimioterapia Combinada , Ácido Gálico/análogos & derivados , Ácido Gálico/farmacología , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Relación Estructura-Actividad
19.
World J Acupunct Moxibustion ; 30(3): 167-170, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32837109

RESUMEN

A case of the absorption of corona virus disease 2019 (COVID-19) promoted by professor Xu ZOU's acupuncture technique for "benefiting kidney and strengthening anti-pathogenic qi" is introduced. A female patient suffered from COVID-19, 64 years old, had been treated with acupuncture and Chinese herb granules for 10 days on the base of the oral administration of moxifloxacin. In the re-examination, the chest CT image indicated that the absorption of COVID-19 was obvious as compared with before, the nucleic acid test of novel corona virus was negative and the patient narrated no obvious discomfort. Acupuncture therapy plays its active adjuvant effect in the whole process of the treatment of COVID-19.

20.
Gut Pathog ; 12: 2, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31921356

RESUMEN

BACKGROUND: The prevalence of human infections with the zoonotic pathogen Campylobacter jejuni is rising worldwide. Therefore, the identification of compounds with potent anti-pathogenic and anti-inflammatory properties for future therapeutic and/or preventive application to combat campylobacteriosis is of importance for global health. Results of recent studies suggested carvacrol (4-isopropyl-2-methylphenol) as potential candidate molecule for the treatment of campylobacteriosis in humans and for the prevention of Campylobacter colonization in farm animals. RESULTS: To address this in a clinical murine infection model of acute campylobacteriosis, secondary abiotic IL-10-/- mice were subjected to synthetic carvacrol via the drinking water starting 4 days before peroral C. jejuni challenge. Whereas at day 6 post-infection placebo treated mice suffered from acute enterocolitis, mice from the carvacrol cohort not only harbored two log orders of magnitude lower pathogen loads in their intestines, but also displayed significantly reduced disease symptoms. Alleviated campylobacteriosis following carvacrol application was accompanied by less distinct intestinal apoptosis and pro-inflammatory immune responses as well as by higher numbers of proliferating colonic epithelial cells. Remarkably, the inflammation-ameliorating effects of carvacrol treatment were not restricted to the intestinal tract, but could also be observed in extra-intestinal organs such as liver, kidneys and lungs and, strikingly, systemically as indicated by lower IFN-γ, TNF, MCP-1 and IL-6 serum concentrations in carvacrol versus placebo treated mice. Furthermore, carvacrol treatment was associated with less frequent translocation of viable C. jejuni originating from the intestines to extra-intestinal compartments. CONCLUSION: The lowered C. jejuni loads and alleviated symptoms observed in the here applied clinical murine model for human campylobacteriosis highlight the application of carvacrol as a promising novel option for both, the treatment of campylobacteriosis and hence, for prevention of post-infectious sequelae in humans, and for the reduction of C. jejuni colonization in the intestines of vertebrate lifestock animals.

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