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

RESUMO

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


Assuntos
Aminoácidos/química , Aminoácidos/farmacologia , Bacteroidetes/metabolismo , Glicerofosfolipídeos/química , Glicerofosfolipídeos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Técnicas de Tipagem Bacteriana/métodos
2.
Pan Afr Med J ; 38: 383, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381527

RESUMO

Introduction: lower respiratory tract infections (LRTIs) are infections involving the trachea, primary bronchi and lungs. People with LRTIs typically experience coughs as the primary symptoms; however, shortness of breath, weakness, fever and fatigue may be coupled with the cough. It is common among the aged, children under five and the immune-suppressed. Persons with symptoms suggestive of pulmonary tuberculosis (TB) may have tuberculosis, other respiratory tract infection or co-infection of tuberculosis and other respiratory pathogens. This study aimed to identify the presence of pathogens in sputum of suspected tuberculosis cases and their antimicrobial resistance patterns. Methods: this was a retrospective study conducted from September 2018 to November 2019 at Tamale Public Health Laboratory. Sputum or gastric lavage samples were collected from persons with suspected clinical presentations of TB and/or LRTI. These samples were cultured using standard microbiological protocols and antimicrobial susceptibility test performed on the positive cultures by Kirby-Bauer disc diffusion method. Molecular identification of M. tuberculosis was performed on all the suspected TB cases using GeneXpert mycobacterium tuberculosis/rifampin (MTB/RIF) assay. Results: during the study period, there were 264 cases of which 49.2% were males and 50.8% were females. Positive cases for culture were 47.3%. Out of the 264 cases, 186 (70.5%) were suspected TB with 51.6% being positive for culture, 6.5% positive for M. tuberculosis (GeneXpert confirmed) and 3.8% co-infection of TB with other bacteria pathogens. Klebsiella spp. (35/125; 28%) and Pseudomonas spp. (19/125; 15.2%) were the most predominant pathogens isolated. There was no significant difference in detection of bacteria in males and females (p=0.89), however individuals with suspected TB were significantly infected with other bacterial species than the unsuspected individuals (p=0.03). Almost all the isolates showed high susceptibility towards carbapenem (meropenem) and high resistance towards the third generation cephalosporins (cefotaxime and ceftriaxone). Conclusion: this study highlights the need to test individuals with classical symptoms of LRTIs for other bacterial infections other than TB only. Sputum culture is recommended for all suspected tuberculosis cases to provide accurate laboratory diagnosis to LRTIs and mitigate unnecessary use of antimicrobials.


Assuntos
Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , Infecções Respiratórias/microbiologia , Escarro/microbiologia , Adulto , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/epidemiologia , Estudos Transversais , Feminino , Lavagem Gástrica , Humanos , Masculino , Testes de Sensibilidade Microbiana , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Estudos Retrospectivos , Adulto Jovem
3.
Pan Afr Med J ; 38: 409, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381553

RESUMO

Introduction: the crude mortality rate due to infectious diseases in India is approximately 417 per one lakh persons and pyogenic infections are one of the significant contributor. Poor antimicrobial stewardship in India has led to an increase in multidrug resistant superbugs in both community as well as hospital settings. The aim of this study was to identify the bacterial etiology of pyogenic infections and to evaluate their antimicrobial resistance profile. Methods: this is a retrospective observational study from January, 2018 to December, 2018. A total 1851 samples, collected as a part of patient care were included in this study. Specimens were subjected to culture on Blood agar and MacConkey agar and incubated at 37°C for 48 hours. Species identification was done as per standard laboratory protocol. Antimicrobial susceptibility testing was performed using Kirby-Bauer disc diffusion according to Clinical and Laboratory Standards Institute guidelines. Results: of total 1851 samples, culture was positive in 61.54%. A total 70.59%, Gram negative organisms were isolated followed by Gram positive cocci in 45.48%, yeast in 1.05%, coryneform bacteria in 0.79% and in one case, non-tubercular mycobacteria was isolated. Staphylococcus aureus (30.9%) was the predominant organism isolated. Most common multi drug resistant isolates were Klebsiella spp. (74.79%) and Acinetobacter spp. (74.32%). Conclusion: this study gives an insight about the prevalence and common etiology of pyogenic infections along with their antimicrobial resistance profile in north western region of India. This study will contribute in formulating antibiotic stewardship program by selecting the antibiograms of pyogenic isolates.


Assuntos
Antibacterianos/farmacologia , Bactérias/isolamento & purificação , Infecções Bacterianas/epidemiologia , Adulto , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana Múltipla , Feminino , Humanos , Índia/epidemiologia , Masculino , Prevalência , Estudos Retrospectivos , Adulto Jovem
4.
J Microbiol ; 59(9): 827-839, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34382149

RESUMO

Probiotics effectively prevent and improve metabolic diseases such as diabetes by regulating the intestinal microenvironment and gut microbiota. However, the effects of probiotics in gestational diabetes mellitus are not clear. Here, we showed that probiotic supplements significantly improved fasting blood glucose in a gestational diabetes mellitus rat model. To further understand the mechanisms of probiotics in gestational diabetes mellitus, the gut microbiota were analyzed via 16S rRNA sequencing. We found that compared with the normal pregnant group, the gestational diabetes mellitus rats had decreased diversity of gut microbiota. Moreover, probiotic supplementation restored the diversity of the gut microbiota in gestational diabetes mellitus rats, and the gut microbiota structure tended to be similar to that of normal pregnant rats. In particular, compared with gestational diabetes mellitus rats, the abundance of Firmicutes and Actinobacteria was higher after probiotic supplementation. Furthermore, activating carbohydrate metabolism and membrane transport pathways may be involved in the potential mechanisms by which probiotic supplements alleviate gestational diabetes mellitus. Overall, our results suggested that probiotic supplementation might be a novel approach to restore the gut microbiota of gestational diabetes mellitus rats and provided an experimental evidence for the use of probiotic supplements to treat gestational diabetes mellitus.


Assuntos
Diabetes Gestacional/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Probióticos/administração & dosagem , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/metabolismo , Metabolismo dos Carboidratos , Carboidratos , Diabetes Gestacional/metabolismo , Diabetes Gestacional/microbiologia , Suplementos Nutricionais/análise , Feminino , Masculino , Gravidez , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Ratos , Ratos Sprague-Dawley
5.
Int J Mol Sci ; 22(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34445625

RESUMO

Arthropod antimicrobial peptides (AMPs) offer a promising source of new leads to address the declining number of novel antibiotics and the increasing prevalence of multidrug-resistant bacterial pathogens. AMPs with potent activity against Gram-negative bacteria and distinct modes of action have been identified in insects and scorpions, allowing the discovery of AMP combinations with additive and/or synergistic effects. Here, we tested the synergistic activity of two AMPs, from the dung beetle Copris tripartitus (CopA3) and the scorpion Heterometrus petersii (Hp1090), against two strains of Escherichia coli. We also tested the antibacterial activity of two hybrid peptides generated by joining CopA3 and Hp1090 with linkers comprising two (InSco2) or six (InSco6) glycine residues. We found that CopA3 and Hp1090 acted synergistically against both bacterial strains, and the hybrid peptide InSco2 showed more potent bactericidal activity than the parental AMPs or InSco6. Molecular dynamics simulations revealed that the short linker stabilizes an N-terminal 310-helix in the hybrid peptide InSco2. This secondary structure forms from a coil region that interacts with phosphatidylethanolamine in the membrane bilayer model. The highest concentration of the hybrid peptides used in this study was associated with stronger hemolytic activity than equivalent concentrations of the parental AMPs. As observed for CopA3, the increasing concentration of InSco2 was also cytotoxic to BHK-21 cells. We conclude that AMP hybrids linked by glycine spacers display potent antibacterial activity and that the cytotoxic activity can be modulated by adjusting the nature of the linker peptide, thus offering a strategy to produce hybrid peptides as safe replacements or adjuncts for conventional antibiotic therapy.


Assuntos
Antibacterianos/farmacologia , Artrópodes/química , Bactérias/efeitos dos fármacos , Glicina/química , Hemólise/efeitos dos fármacos , Rim/efeitos dos fármacos , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Animais , Antibacterianos/química , Apoptose , Células Cultivadas , Cricetinae , Camundongos , Proteínas Citotóxicas Formadoras de Poros/química
6.
Malawi Med J ; 33(1): 59-64, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-34422235

RESUMO

Background: Non-susceptibility of bacteria to antiseptic agents used for preoperative skin preparations threaten the effectiveness of prevention of surgical site infections. Data concerning susceptibility of multidrug resistant bacteria strains to antiseptic agents was limited at our setting. This study presents the susceptibility of extended spectrum ß-lactamases producing Klebsiella pneumoniae and Escherichia coli (with and without biofilm formation) to antiseptic agents used for preoperative skin preparations at zonal referral hospital in Mwanza, Tanzania. Methods: This cross-sectional descriptive study was conducted through July 2020. Presumptive extended spectrum beta-lactamase producing Klebsiella pneumoniae and Escherichia coli were recovered for this study. Disc combination method was used to confirm production of ESBL while tube method was used to detect biofilms formation. Then, isolates were tested for susceptibility towards 10% povidone iodine, 70% methylated spirit, 50% hydrogen peroxide (6% of industrial H2O2 diluted in equal volume with sterile distilled water) and 2% chlorhexidine. STATA software version 13.0 was used for data analysis. Results: A total of 31 presumptive ESBL producers were recovered and phenotypically confirmed, whereas 54.8% (n=17) were K. pneumoniae and 45.2% (n=14) were E. coli. Five (35.7%) E. coli and seven (41.2%) K. pneumoniae had positive biofilms test results. Four (12.9%) bacteria were non-susceptible to antiseptic agents used for preoperative skin preparations. However, none exhibited resistance towards 10% PVP-I. Conclusion: In this study we highlight the existence of multidrug resistant Gram-negative bacteria with resistance to antiseptic agents used for preoperative skin preparation at a zonal referral hospital in Mwanza, Tanzania.


Assuntos
Anti-Infecciosos Locais/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos Locais/uso terapêutico , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Biofilmes , Estudos Transversais , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/isolamento & purificação , Humanos , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Tanzânia
7.
Nat Commun ; 12(1): 4765, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362925

RESUMO

Antibiotic resistance genes (ARGs) are widespread among bacteria. However, not all ARGs pose serious threats to public health, highlighting the importance of identifying those that are high-risk. Here, we developed an 'omics-based' framework to evaluate ARG risk considering human-associated-enrichment, gene mobility, and host pathogenicity. Our framework classifies human-associated, mobile ARGs (3.6% of all ARGs) as the highest risk, which we further differentiate as 'current threats' (Rank I; 3%) - already present among pathogens - and 'future threats' (Rank II; 0.6%) - novel resistance emerging from non-pathogens. Our framework identified 73 'current threat' ARG families. Of these, 35 were among the 37 high-risk ARGs proposed by the World Health Organization and other literature; the remaining 38 were significantly enriched in hospital plasmids. By evaluating all pathogen genomes released since framework construction, we confirmed that ARGs that recently transferred into pathogens were significantly enriched in Rank II ('future threats'). Lastly, we applied the framework to gut microbiome genomes from fecal microbiota transplantation donors. We found that although ARGs were widespread (73% of genomes), only 8.9% of genomes contained high-risk ARGs. Our framework provides an easy-to-implement approach to identify current and future antimicrobial resistance threats, with potential clinical applications including reducing risk of microbiome-based interventions.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Bactérias/efeitos dos fármacos , Bactérias/genética , Bases de Dados Factuais , Microbioma Gastrointestinal/efeitos dos fármacos , Genes Bacterianos/efeitos dos fármacos , Genoma , Humanos , Metagenoma , Plasmídeos
8.
Int J Mol Sci ; 22(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34445403

RESUMO

Natural smectites have demonstrated efficacy in the treatment of diarrhea. The present study evaluated the prophylactic effect of a diosmectite (FI5pp) on the clinical course, colon damage, expression of tight junction (TJ) proteins and the composition of the gut microbiota in dextran sulfate sodium (DSS) colitis. Diosmectite was administered daily to Balb/c mice from day 1 to 7 by oral gavage, followed by induction of acute DSS-colitis from day 8 to 14 ("Control", n = 6; "DSS", n = 10; "FI5pp + DSS", n = 11). Mice were sacrificed on day 21. Clinical symptoms (body weight, stool consistency and occult blood) were checked daily after colitis induction. Colon tissue was collected for histological damage scoring and quantification of tight junction protein expression. Stool samples were collected for microbiome analysis. Our study revealed prophylactic diosmectite treatment attenuated the severity of DSS colitis, which was apparent by significantly reduced weight loss (p = 0.022 vs. DSS), disease activity index (p = 0.0025 vs. DSS) and histological damage score (p = 0.023 vs. DSS). No significant effects were obtained for the expression of TJ proteins (claudin-2 and claudin-3) after diosmectite treatment. Characterization of the microbial composition by 16S amplicon NGS showed that diosmectite treatment modified the DSS-associated dysbiosis. Thus, diosmectites are promising candidates for therapeutic approaches to target intestinal inflammation and to identify possible underlying mechanisms of diosmectites in further studies.


Assuntos
Bactérias/classificação , Colite/tratamento farmacológico , Sulfato de Dextrana/efeitos adversos , Microbiota/efeitos dos fármacos , Silicatos/administração & dosagem , Administração Oral , Animais , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Peso Corporal/efeitos dos fármacos , Colite/induzido quimicamente , Colite/metabolismo , Colite/microbiologia , DNA Bacteriano/genética , DNA Ribossômico/genética , Fezes/microbiologia , Masculino , Camundongos Endogâmicos BALB C , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Índice de Gravidade de Doença , Silicatos/farmacologia , Proteínas de Junções Íntimas/metabolismo , Resultado do Tratamento
9.
Inorg Chem ; 60(17): 12730-12734, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34382773

RESUMO

Can a minor difference in the nonmetal binding sequence of antimicrobial clavanins explain the drastic change in the coordination environment and antimicrobial efficiency? This study answers the question with a definite "yes", showing the details of the bioinorganic chemistry of Zn(II) and Cu(II) complexes with clavanins, histidine-rich, antimicrobial peptides from hemocytes of the tunicate Styela clava.


Assuntos
Antibacterianos/farmacologia , Proteínas Sanguíneas/farmacologia , Complexos de Coordenação/farmacologia , Sequência de Aminoácidos , Antibacterianos/química , Antibacterianos/toxicidade , Bactérias/efeitos dos fármacos , Proteínas Sanguíneas/química , Proteínas Sanguíneas/toxicidade , Candida albicans/efeitos dos fármacos , Linhagem Celular , Complexos de Coordenação/química , Complexos de Coordenação/toxicidade , Cobre/química , Humanos , Testes de Sensibilidade Microbiana , Zinco/química
10.
Molecules ; 26(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34443349

RESUMO

Ulva sp. is known to be a source of bioactive compounds such as ulvans, but to date, their biological activity on skin commensal and/or opportunistic pathogen bacteria has not been reported. In this study, the effects of poly- and oligosaccharide fractions produced by enzyme-assisted extraction and depolymerization were investigated, for the first time in vitro, on cutaneous bacteria: Staphylococcus aureus, Staphylococcus epidermidis, and Cutibacterium acnes. At 1000 µg/mL, poly- and oligosaccharide fractions did not affect the growth of the bacteria regarding their generation time. Polysaccharide Ulva sp. fractions at 1000 µg/mL did not alter the bacterial biofilm formation, while oligosaccharide fractions modified S. epidermidis and C. acnes biofilm structures. None of the fractions at 1000 µg/mL significantly modified the cytotoxic potential of S. epidermidis and S. aureus towards keratinocytes. However, poly- and oligosaccharide fractions at 1000 µg/mL induced a decrease in the inflammatory potential of both acneic and non-acneic C. acnes strains on keratinocytes of up to 39.8%; the strongest and most significant effect occurred when the bacteria were grown in the presence of polysaccharide fractions. Our research shows that poly- and oligosaccharide Ulva sp. fractions present notable biological activities on cutaneous bacteria, especially towards C. acnes acneic and non-acneic strains, which supports their potential use for dermo-cosmetic applications.


Assuntos
Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Microbiota/efeitos dos fármacos , Extratos Vegetais/farmacologia , Pele/microbiologia , Ulva/química , Bactérias/patogenicidade , Relação Dose-Resposta a Droga , Propionibacteriaceae/efeitos dos fármacos , Propionibacteriaceae/crescimento & desenvolvimento , Propionibacteriaceae/patogenicidade , Propionibacteriaceae/fisiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/patogenicidade , Staphylococcus aureus/fisiologia , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/crescimento & desenvolvimento , Staphylococcus epidermidis/patogenicidade , Staphylococcus epidermidis/fisiologia , Virulência/efeitos dos fármacos
11.
Molecules ; 26(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34443481

RESUMO

This study explores the capability of Sulfate Radical-based Advanced Oxidation Processes (SR-AOPs) for the simultaneous disinfection and decontamination of urban wastewater. Sulfate and hydroxyl radicals in solution were generated activating peroxymonosulfate (PMS) under UV-C irradiation at pilot plant scale. The efficiency of the process was assessed toward the removal of three CECs (Trimethoprim (TMP), Sulfamethoxazole (SMX), and Diclofenac (DCF)) and three bacteria (Escherichia coli, Enterococcus spp., and Pseudomonas spp.) in actual urban wastewater (UWW), obtaining the optimal value of PMS at 0.5 mmol/L. Under such experimental conditions, bacterial concentration ≤ 10 CFU/100 mL was reached after 15 min of UV-C treatment (0.03 kJ/L of accumulative UV-C radiation) for natural occurring bacteria, no bacterial regrowth was observed after 24 and 48 h, and 80% removal of total CECs was achieved after 12 min (0.03 kJ/L), with a release of sulfate ions far from the limit established in wastewater discharge. Moreover, the inactivation of Ampicillin (AMP), Ciprofloxacin (CPX), and Trimethoprim (TMP) antibiotic-resistant bacteria (ARB) and reduction of target genes (ARGs) were successfully achieved. Finally, a harmful effect toward the receiving aquatic environment was not observed according to Aliivibrio fischeri toxicity tests, while a slightly toxic effect toward plant growth (phytotoxicity tests) was detected. As a conclusion, a cost analysis demonstrated that the process could be feasible and a promising alternative to successfully address wastewater reuse challenges.


Assuntos
Peróxidos/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água/métodos , Aliivibrio fischeri/efeitos dos fármacos , Antibacterianos/química , Bactérias/efeitos dos fármacos , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Resistência Microbiana a Medicamentos/genética , Oxirredução , Plantas/efeitos dos fármacos , Sulfatos/química , Raios Ultravioleta , Águas Residuárias/análise , Águas Residuárias/microbiologia , Águas Residuárias/toxicidade , Poluentes Químicos da Água/efeitos da radiação
12.
Molecules ; 26(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34443509

RESUMO

The main goal of this work was to study the structural transformation of humic acids (HAs) under the influence of selected strains of fungi (Aspergillus niger and Paecilomyces lilacinus) and bacteria (Bacillus sp., Paenibacillus polymyxa and Bacillus amyloliquefaciens) with/without the presence of NPK fertilizers. Two-year experiments were conducted on two different soils and HAs isolated from these soils were examined for structure, humification degree, and quantity using fluorescence and UV-Vis spectroscopy, elemental analysis, and extraction methods. Results showed that the applied additives contributed to the beneficial transformation of HAs, but effects differed for various soils. HAs from silty soil with higher organic carbon content showed simplification of their structure, and decreases in humification, molecular weight, and aromaticity under the influence of fungi and bacteria without NPK, and with NPK alone. With both fungi and NPK, increases in O/H and O/C atomic ratios indicated an increase in the number of O-containing functional groups. HAs from sandy soil did not show as many significant changes as did those from silty soil. Sandy soil exhibited a strong decline in HA content in the second year that was reduced/neutralized by the presence of fungi, bacteria, and NPK. Periodically observed fluorescence at ~300 nm/450 nm reflected formation of low-molecular HAs originating from the activity of microorganisms.


Assuntos
Agricultura , Bactérias/efeitos dos fármacos , Fertilizantes/análise , Fungos/efeitos dos fármacos , Substâncias Húmicas/análise , Minerais/farmacologia , Solo/química , Fluorescência , Espectrofotometria Ultravioleta
13.
Molecules ; 26(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34443371

RESUMO

The purpose of this study was to clarify the effects of biochar on the diversity of bacteria and fungi in the rice root zone and to reveal the changes in soil microbial community structure in the root zone after biochar application to provide a scientific basis for the improvement of albic soil. Rice and corn stalk biochar were mixed with albic soil in a pot experiment. Soil samples were collected at the rice maturity stage, soil nutrients were determined, and genomic DNA was extracted. The library was established using polymerase chain reaction (PCR) amplification. The abundance, diversity index, and community structure of the soil bacterial 16SrRNA gene V3 + V4 region and the fungal internal transcribed spacer-1 (ITS1) region were analyzed using Illumina second-generation high-throughput sequencing technology on the MiSeq platform with related bioinformatics. The results revealed that the biochar increased the soil nutrient content of albic soil. The bacteria ACE indexes of treatments of rice straw biochar (SD) and corn straw biochar (SY) were increased by 3.10% and 2.06%, respectively, and the fungi ACE and Chao indices of SD were increased by 7.86% and 14.16%, respectively, compared to conventional control treatment with no biochar (SBCK). The numbers of bacterial and fungal operational taxonomic units (OUT) in SD and SY were increased, respectively, compared to that of SBCK. The relationship between soil bacteria and fungi in the biochar-treated groups was stronger than that in the SBCK. The bacterial and fungal populations were correlated with soil nutrients, which suggested that the impacts of biochar on the soil bacteria and fungi community were indirectly driven by alternation of soil nutrient characteristics. The addition of two types of biochar altered the soil microbial community structure and the effect of rice straw biochar treatment on SD was more pronounced. This study aimed to provide a reference and basic understanding for albic soil improvement by biochar, with good application prospects.


Assuntos
Carvão Vegetal/farmacologia , Microbiota/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Rizosfera , Solo , Bactérias/efeitos dos fármacos , Biodiversidade , Fungos/efeitos dos fármacos , Nutrientes/análise , Oryza/efeitos dos fármacos , Filogenia , Microbiologia do Solo
14.
Molecules ; 26(16)2021 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-34443670

RESUMO

Enterococci and methicillin-resistant S. aureus (MRSA) are among the menacing bacterial pathogens. Novel antibiotics are urgently needed to tackle these antibiotic-resistant bacterial infections. This article reports the design, synthesis, and antimicrobial studies of 30 novel pyrazole derivatives. Most of the synthesized compounds are potent growth inhibitors of planktonic Gram-positive bacteria with minimum inhibitory concertation (MIC) values as low as 0.25 µg/mL. Further studies led to the discovery of several lead compounds, which are bactericidal and potent against MRSA persisters. Compounds 11, 28, and 29 are potent against S. aureus biofilms with minimum biofilm eradication concentration (MBEC) values as low as 1 µg/mL.


Assuntos
Bactérias/crescimento & desenvolvimento , Farmacorresistência Bacteriana/efeitos dos fármacos , Inibidores do Crescimento/síntese química , Inibidores do Crescimento/farmacologia , Pirazóis/síntese química , Pirazóis/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/fisiologia , Inibidores do Crescimento/química , Células HEK293 , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/fisiologia , Testes de Sensibilidade Microbiana , Pirazóis/química
15.
Molecules ; 26(15)2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34361576

RESUMO

Prunus mahaleb L. fruit has long been used in the production of traditional liqueurs. The fruit also displayed scavenging and reducing activity, in vitro. The present study focused on unravelling peripheral and central protective effects, antimicrobial but also anti-COVID-19 properties exerted by the water extract of P. mahaleb. Anti-inflammatory effects were studied in isolated mouse colons exposed to lipopolysaccharide. Neuroprotection, measured as a blunting effect on hydrogen-peroxide-induced dopamine turnover, was investigated in hypothalamic HypoE22 cells. Antimicrobial effects were tested against different Gram+ and Gram- bacterial strains. Whereas anti-COVID-19 activity was studied in lung adenocarcinoma H1299 cells, where the gene expression of ACE2 and TMPRSS2 was measured after extract treatment. The bacteriostatic effects induced on Gram+ and Gram- strains, together with the inhibition of COX-2, TNFα, HIF1α, and VEGFA in the colon, suggest the potential of P. mahaleb water extract in contrasting the clinical symptoms related to ulcerative colitis. The inhibition of the hydrogen peroxide-induced DOPAC/DA ratio indicates promising neuroprotective effects. Finally, the downregulation of the gene expression of ACE2 and TMPRSS2 in H1299 cells, suggests the potential to inhibit SARS-CoV-2 virus entry in the human host. Overall, the results support the valorization of the local cultivation of P. mahaleb.


Assuntos
Bactérias/efeitos dos fármacos , Colo/efeitos dos fármacos , Neuroproteção , Extratos Vegetais/farmacologia , SARS-CoV-2/efeitos dos fármacos , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antivirais/química , Antivirais/farmacologia , COVID-19 , Linhagem Celular , Colite Ulcerativa/tratamento farmacológico , Citocinas/genética , Citocinas/metabolismo , Dopamina/metabolismo , Frutas/química , Regulação da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Humanos , Inflamação/tratamento farmacológico , Masculino , Camundongos , Extratos Vegetais/química , Prunus/química , Serina Endopeptidases/metabolismo
16.
Int J Mol Sci ; 22(15)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34360657

RESUMO

Although some metallic nanoparticles (NPs) are commonly used in the food processing plants as nanomaterials for food packaging, or as coatings on the food handling equipment, little is known about antimicrobial properties of palladium (PdNPs) and platinum (PtNPs) nanoparticles and their potential use in the food industry. In this study, common food-borne pathogens Salmonella enterica Infantis, Escherichia coli, Listeria monocytogenes and Staphylococcus aureus were tested. Both NPs reduced viable cells with the log10 CFU reduction of 0.3-2.4 (PdNPs) and 0.8-2.0 (PtNPs), average inhibitory rates of 55.2-99% for PdNPs and of 83.8-99% for PtNPs. However, both NPs seemed to be less effective for biofilm formation and its reduction. The most effective concentrations were evaluated to be 22.25-44.5 mg/L for PdNPs and 50.5-101 mg/L for PtNPs. Furthermore, the interactions of tested NPs with bacterial cell were visualized by transmission electron microscopy (TEM). TEM visualization confirmed that NPs entered bacteria and caused direct damage of the cell walls, which resulted in bacterial disruption. The in vitro cytotoxicity of individual NPs was determined in primary human renal tubular epithelial cells (HRTECs), human keratinocytes (HaCat), human dermal fibroblasts (HDFs), human epithelial kidney cells (HEK 293), and primary human coronary artery endothelial cells (HCAECs). Due to their antimicrobial properties on bacterial cells and no acute cytotoxicity, both types of NPs could potentially fight food-borne pathogens.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Doenças Transmitidas por Alimentos/prevenção & controle , Nanopartículas Metálicas/administração & dosagem , Paládio/química , Platina/química , Antibacterianos/química , Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Microbiologia de Alimentos , Humanos , Rim/citologia , Rim/efeitos dos fármacos , Nanopartículas Metálicas/química
17.
Nutrients ; 13(7)2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34371869

RESUMO

Hibiscus sabdariffa L. (H.s.) is a polyphenolic-rich plant commonly consumed either as a beverage or spice. The aim of the present study was to evaluate the in vitro digestibility of H.s. polyphenols using an in vitro model of digestion which simulates the human stomach and small intestine. The bioaccessible polyphenols released in the digested samples were analyzed by liquid chromatography coupled to photodiode array and mass spectrometry detection. H.s. anthocyanins (cyanidin-3-O-sambubioside and delphinidin-3-O-sambubioside) content drastically dropped during the digestion process from 2.91 ± 0.03 µg g-1 and 8.53 ± 0.08 µg g-1 (w/w) CG (Cyanidin-glucoside) in the raw extract, respectively, to 0.12 ± 0.01 µg g-1 0.12 ± 0.01 µg g-1 (w/w) CG at the end of duodenal digestion. Total polyphenols also have shown a decrease from 1192.65 ± 30.37 µg g-1 (w/w) in the raw extract to 282.24 ± 7.21 µg g-1 (w/w) by the end of gastric digestion, in contrast to their increase by the end of duodenal digestion 372.91 ± 3.97 µg g-1 (w/w). On the other hand, the decrease in certain compounds (e.g., caffeoylquinicandcoumaroylquinic acids) was observed during gastric digestion resulting in an increase of quinic acid in the duodenal aliquots, thus suggesting that this compound was derived from the degradation of the more complex hydroxycinnamic acids. H.s. extract also exhibited a bacteriostatic effect against Staphylococcus aureus ATCC 6538 (MIC of 2.5 mg mL-1) and a bactericidal effect against a food isolate of Listeria monocytogenes (MBC of 2.5 mg mL-1). The undigested polyphenols of H.s. in the upper gastrointestinal tract enters the colon, where they are metabolized by the gut microbiota. The present study results showed that resistance of H.s. polyphenols during gastrointestinal digestion might affect their uptake, resulting in a decrease in their digestibility.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Digestão , Hibiscus , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Antibacterianos/isolamento & purificação , Antibacterianos/metabolismo , Bactérias/crescimento & desenvolvimento , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Suco Gástrico/química , Hibiscus/química , Humanos , Secreções Intestinais/química , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Polifenóis/isolamento & purificação , Polifenóis/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Espectrometria de Massas em Tandem
18.
Int J Nanomedicine ; 16: 4631-4642, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262273

RESUMO

Purpose: Antibiotic-resistant bacteria are pathogens that have emerged as a serious public health risk. Thus, there is an urgent need to develop a new generation of anti-bacterial materials to kill antibiotic-resistant bacteria. Methods: Nanosilver-decorated mesoporous organosilica nanoparticles (Ag-MONs) were fabricated for co-delivery of gentamicin (GEN) and nanosilver. After investigating the glutathione (GSH)-responsive matrix degradation and controlled release of both GEN and silver ions, the anti-bacterial activities of Ag-MONs@GEN were systematically determined against several antibiotic-susceptible and antibiotic-resistant bacteria including Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis. Furthermore, the cytotoxic profiles of Ag-MONs@GEN were evaluated. Results: The GEN-loaded nanoplatform (Ag-MONs@GEN) showed glutathione-responsive matrix degradation, resulting in the simultaneous controlled release of GEN and silver ions. Ag-MONs@GEN exhibited excellent anti-bacterial activities than Ag-MONs and GEN alone via inducing ROS generation, especially enhancing synergetic effects against four antibiotic-resistant bacteria including Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis. Moreover, the IC50 values of Ag-MONs@GEN in L929 and HUVECs cells were 313.6 ± 15.9 and 295.7 ± 12.3 µg/mL, respectively, which were much higher than their corresponding minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values. Conclusion: Our study advanced the development of Ag-MONs@GEN for the synergistic and safe treatment of antibiotic-resistant bacteria.


Assuntos
Resistência Microbiana a Medicamentos/efeitos dos fármacos , Gentamicinas/farmacologia , Glutationa/química , Nanopartículas/química , Dióxido de Silício/química , Prata/química , Animais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Liberação Controlada de Fármacos , Sinergismo Farmacológico , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Nanopartículas/ultraestrutura
19.
Molecules ; 26(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199466

RESUMO

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of the gastrointestinal tract with an incompletely understood pathogenesis. Long-standing colitis is associated with increased risk of colon cancer. Despite the availability of various anti-inflammatory and immunomodulatory drugs, many patients fail to respond to pharmacologic therapy and some experience drug-induced adverse events. Dietary supplements, particularly saffron (Crocus sativus), have recently gained an appreciable attention in alleviating some symptoms of digestive diseases. In our study, we investigated whether saffron may have a prophylactic effect in a murine colitis model. Saffron pre-treatment improved the gross and histopathological characteristics of the colonic mucosa in murine experimental colitis. Treatment with saffron showed a significant amelioration of colitis when compared to the vehicle-treated mice group. Saffron treatment significantly decreased secretion of serotonin and pro-inflammatory cytokines, such as TNF-α, IL-1ß, and IL-6, in the colon tissues by suppressing the nuclear translocation of NF-κB. The gut microbiome analysis revealed distinct clusters in the saffron-treated and untreated mice in dextran sulfate sodium (DSS)-induced colitis by visualization of the Bray-Curtis diversity by principal coordinates analysis (PCoA). Furthermore, we observed that, at the operational taxonomic unit (OTU) level, Cyanobacteria were depleted, while short-chain fatty acids (SCFAs), such as isobutyric acid, acetic acid, and propionic acid, were increased in saffron-treated mice. Our data suggest that pre-treatment with saffron inhibits DSS-induced pro-inflammatory cytokine secretion, modulates gut microbiota composition, prevents the depletion of SCFAs, and reduces the susceptibility to colitis.


Assuntos
Bactérias/classificação , Produtos Biológicos/administração & dosagem , Colite/tratamento farmacológico , Crocus/química , Sulfato de Dextrana/efeitos adversos , Microbiota/efeitos dos fármacos , Administração Oral , Animais , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Produtos Biológicos/farmacologia , Colite/induzido quimicamente , Colite/imunologia , Colite/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Filogenia , Profilaxia Pré-Exposição , Serotonina/metabolismo , Resultado do Tratamento
20.
Molecules ; 26(13)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206736

RESUMO

Green tea can influence the gut microbiota by either stimulating the growth of specific species or by hindering the development of detrimental ones. At the same time, gut bacteria can metabolize green tea compounds and produce smaller bioactive molecules. Accordingly, green tea benefits could be due to beneficial bacteria or to microbial bioactive metabolites. Therefore, the gut microbiota is likely to act as middle man for, at least, some of the green tea benefits on health. Many health promoting effects of green tea seems to be related to the inter-relation between green tea and gut microbiota. Green tea has proven to be able to correct the microbial dysbiosis that appears during several conditions such as obesity or cancer. On the other hand, tea compounds influence the growth of bacterial species involved in inflammatory processes such as the release of LPS or the modulation of IL production; thus, influencing the development of different chronic diseases. There are many studies trying to link either green tea or green tea phenolic compounds to health benefits via gut microbiota. In this review, we tried to summarize the most recent research in the area.


Assuntos
Bactérias/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Chá , Animais , Antioxidantes/farmacologia , Catequina/farmacologia , Disbiose/complicações , Disbiose/tratamento farmacológico , Humanos , Inflamação/metabolismo , Neoplasias/complicações , Neoplasias/metabolismo , Obesidade/complicações , Obesidade/metabolismo , Fenóis/química , Fenóis/metabolismo , Polifenóis/farmacologia , Chá/química
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