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Multidrug-resistant pathogens are now thought to be the primary global causes of disease and death. Therefore, it is imperative to develop new effective bioactive compounds from microbial sources, such as Streptomyces species. Nevertheless, the pharmaceutical industry suffered financial losses and low-quality end products as a result of Streptomyces bacteriophage contamination. To reduce the likelihood of phage-induced issues in the medical industry, it is crucial to develop a method for finding phage-resistant strains. Hence, we aimed to isolate and characterize Streptomyces spp. and Streptomyces phages from various rhizospheric soil samples in Egypt and to investigate their antibacterial activities. Moreover, we targeted development of a Streptomyces phage-resistant strain to extract its active metabolites and further testing its antibacterial activity. Herein, the antibacterial activities of the isolated 58 Streptomyces isolates showed that 10 (17.2 %) Streptomyces isolates had antibacterial activities against the tested bacteria including Listeria monocytogenes, E. coli O157, Acinetobacter baumannii, methicillin resistant-vancomycin-intermediate Staphylococcus aureus (MRSA-VISA) and Micrococcus luteus. Three lytic bacteriophages (ÏPRSC1, ÏPRSC2, and ÏPRSC4) belonging to the families Siphoviridae and Podoviridae were obtained from the rhizospheric soil samples using the most potent S. abietis isolate as the host strain. The three isolated Streptomyces phages were thermostable, ultraviolet stable, infectious, and had a wide range of hosts against the 10 tested Streptomyces isolates with antibacterial activities. The DNA of the ÏPRSC1 and ÏPRSC4 phages were resistant to digestion by EcoRI and HindIII, but the DNA of ÏPRSC2 was resistant to digestion by EcoRI and sensitive to digestion by HindIII. Of note, we developed a S. abietis strain resistant to the three isolated phages and its antibacterial activities were twice that of the wild strain. Finally, telomycin was recognized as an antibacterial metabolite extracted from phage-resistant S. abietis strain, which was potent against the tested Gram-positive bacteria including L. monocytogenes, MRSA-VISA, and M. luteus. Thus, our findings open new horizons for researching substitute antimicrobial medications for both existing and reemerging illnesses.
Assuntos
Antibacterianos , Microbiologia do Solo , Streptomyces , Streptomyces/virologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Egito , Podoviridae/isolamento & purificação , Siphoviridae/isolamento & purificação , Siphoviridae/genética , Bacteriófagos/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/virologia , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/virologia , Micrococcus luteus/efeitos dos fármacos , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/virologia , Aminoglicosídeos/farmacologia , Testes de Sensibilidade Microbiana , RizosferaRESUMO
The worldwide crises from multi-drug-resistant (MDR) bacterial infections are pushing us to search for new alternative therapies. The renewed interest in medicinal plants has gained the attention of our research group. Tamarindus indica L. (T. indica) is one of the traditional medicines used for a wide range of diseases. Therefore, we evaluated the antimicrobial activities of ethanolic extract of T. indica. The inhibitions zones, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and fractional inhibitor concentration indices (FICI) against Gram+ve and -ve pathogens were detected. The bioactive compounds from T. indica extract were identified by mass spectroscopy, thin-layer chromatography, and bio-autographic assay. We performed scanning electron microscopy (SEM) and molecular docking studies to confirm possible mechanisms of actions and antivirulence activities, respectively. We found more promising antimicrobial activities against MDR pathogens with MIC and MBC values for Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa), i.e., (0.78, 3.12 mg/mL) and (1.56, 3.12 mg/mL), respectively. The antimicrobial activities of this extract were attributed to its capability to impair cell membrane permeability, inducing bacterial cell lysis, which was confirmed by the morphological changes observed under SEM. The synergistic interactions between this extract and commonly used antibiotics were confirmed (FICI values < 0.5). The bioactive compounds of this extract were bis (2-ethylhexyl)phthalate, phenol, 2,4-bis(1,1-dimethylethyl), 1,2-benzenedicarboxylic acid, and bis(8-methylnonyl) ester. Additionally, this extract showed antivirulence activities, especially against the S. aureus protease and P. aeruginosa elastase. In conclusion, we hope that pharmaceutical companies can utilize our findings to produce a new formulation of T. indica ethanolic extract with other antibiotics.
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BACKGROUND: Association between Helicobacter pylori (H. pylori) and chronic hepatitis C (CHC) still remains controversial. This work is concerned with assessing the potential role of H. pylori in the progression of hepatitis C virus (HCV)-related chronic liver disease. RESULTS: A total of 449 individuals constituted this study (200 individuals were used to validate the assay while 249 individuals were used to assess the correlation between H. pylori infection and CHC). H. pylori antigen was quantified in serum samples using ELISA. As a consequence, our findings showed that H. pylori positivity was increased significantly (P = 0.021) with liver fibrosis progression as it was found in 44.45% of fibrotic patients and 71.88% of cirrhotic patients. We demonstrated that patients with F4 were accompanied by a significant (P < 0.05) increase in the concentration of H. pylori antigen displaying 16.52-fold and 1.34-fold increase in its level over F0 and F1-F3, respectively. Patients co-infected with H. pylori and HCV are 3.19 times (219%) more likely to experience cirrhosis than those who are mono-infected with HCV. This suggests that the risk for developing F4 was found to increase upon H. pylori co-infection when compared to CHC mono-infected patients. CONCLUSION: The elevated levels of H. pylori-antigen in HCV/H. pylori co-infection suggest increased susceptibility of co-infected patients for promoting hepatic fibrosis progression.
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The limitations in the therapeutic options for foodborne pathogens lead to treatments failure, especially for multidrug-resistant (MDR) Salmonella sp., worldwide. Therefore, we aimed to find alternative and complementary therapies against these resistant foodborne pathogens. Out of 100 meat products samples, the prevalence rate of salmonella was 6%, serotyped only as S. Typhimurium and S. Enteritidis. According to the antibiotic susceptibility assays, the majority of our isolates were MDR and susceptible to cefotaxime. Out of the 13 tested plant extracts, five only showed an inhibition zone in the range of 8-50 mm against both serotypes. Based on their promising activity, the oily extract of cinnamon and aqueous extract of paprika represented the highest potency. Surprisingly, a significant synergistic effect was detected between cinnamon oil and cefotaxime. Depending on Gas Chromatography/Mass Spectrometry (GC-MS), the antimicrobial activity of cinnamon oil was attributed to four components including linalool, camphor, (Z)-3-Phenylacrylaldehyde and its stereoisomer 2-Propenal-3-phenyl. The anti-virulence activities of these compounds were confirmed on the basis of computational molecular docking studies. Accordingly, we recommended the use of cinnamon oil as a food additive to fight the resistant foodborne pathogens. Additionally, we confirmed its therapeutic uses, especially when co-administrated with other antimicrobial agents.
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Mural paintings within the tomb of Setka, Qubbet el-Hawa, in Aswan, Upper Egypt, were investigated using a multi-disciplinary analytical approach (Stereomicroscopy, SEM-EXD and FT-IR spectroscopy). The walls of the tomb were hewn from fragile sandstone and covered by a clay plaster, overlaid by two layers of white gypsum plaster. SEM micrographs were indicative of the penetration of fungal mycelium within the pores of the gypsum plaster, forming white encrustations due to the re-precipitation of gypsum. SEM micrographs revealed that the calcification of the gypsum plaster had occurred due to its exposure to a high temperature. The EDX pattern for the white plaster gave the characteristic spectrum of gypsum, the blue pigment was Egyptian blue, the black pigment was magnetite, the white pigment was of gypsum (or anhydrite) and the yellow pigment was limonite. Finally, the FT-IR spectrum of the binder gave the characteristic features of gum Arabic.
Assuntos
Pinturas , Egito , Microscopia , Pigmentação , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Antibacterial drug resistance is considered one of the biggest threats to human health worldwide, and the overuse of antibiotics accelerates this problem. Multidrug-resistant (MDR) bacteria are becoming harder to treat as the antibiotics used to treat them become less effective. Therefore, it is necessary to evaluate novel methods to control MDR bacteria. In this study, 40 bacterial isolates were collected from diabetic patients. The sensitivity of 40 bacterial isolates to seven antibiotics was evaluated. Four bacterial isolates were resistant to all antibiotic groups. The MDR pathogenic bacteria were selected and identified morphologically and biochemically and confirmed by VITEK® 2 system as follows: Staphylococcus aureus W35, Pseudomonas aeruginosa D31, Klebsiella pneumoniae DF30, and K. pneumoniae B40. Identification of the most resistant P. aeruginosa D31 was confirmed by the sequencing of a 16S ribosomal RNA gene with an accession number (MW241596). The inhibitory activity of eight types of native grown plant extracts against MDR bacteria was studied. Clove alcoholic extract (CAE) showed the highest inhibitory activity against MDR bacteria. Gas chromatography-mass spectrometry analysis of partially purified CAE at 0.9 Rf detected by thin-layer chromatography showed an active compound named hexadecenoic acid methyl ester with the highest antimicrobial effect against clinical pathogenic bacteria. The formation of silver nanoparticles (AgNPs) by CAE was studied. Evaluation of AgNPs was investigated by X-ray diffraction, UV-Vis, and transmission electron microscopy. The antibacterial effect of AgNPs after 2, 4, and 6 days in light and dark conditions was evaluated. Finally, the AgNPs synthesized using CAE possess good inhibition activity against the tested pathogenic bacteria. As a result, the bactericidal components listed above were promising in reducing MDR bacteria and can be used for treatments of bacterial infection and in the development of safe products with a natural base.
Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Nanopartículas Metálicas/química , Palmitatos/química , Prata/química , Antibacterianos/química , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Diabetes Mellitus/microbiologia , Química Verde , Humanos , Testes de Sensibilidade Microbiana , Palmitatos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , RNA Ribossômico 16S/genética , Prata/farmacologia , Syzygium/químicaRESUMO
Bacterial outbreaks caused by Staphylococcus aureus (S. aureus) are interesting due to the existence of multidrug resistant (MDR) isolates. Therefore, there is a need to develop novel ways to control such MDR S. aureus. In this study, some natural agents such as honey bee (HB), extracts of either Moringa oleifera seeds (MSE), or leaves (MLE) and essential oils of garlic, clove, and moringa were studied for their inhibitory activity against this S. aureus pathogen. About 100 food samples including beef luncheon (n = 25), potato chips (n = 50), and corn flakes (n = 25) were investigated for possible pollution with the S. aureus bacteria. The isolated bacteria suspected to belong S. aureus that grew well onto Baird-Parker agar (Oxoid) and shiny halo zones and positive coagulase reaction were selected and identified by API-Kits; all of them that were approved belong to S. aureus (18 strains). The sensitivity of the obtained 18 S. aureus bacterial strains to 12 antibiotics were evaluated; all of them were resistant to ofloxacin; however, other antibiotics tested showed variable results. Interestingly, the S. aureus No. B3 isolated from beef luncheon was resistant to10 antibiotics out of 12 ones tested. Multiple antibiotic resistance index (MAR) of this S. aureus strain was about 83.3%. Therefore, its identification was confirmed by sequencing of a 16S rRNA gene which approved a successful biochemical identification carried out by API Kits and such strain was designated S. aureus LC 554891. The genome of such strain appeared to contain mecA gene encoding methicillin resistance; it was found to contain hla, hlb, tsst-1, and finbA that encode α-blood hemolysis, ß-blood hemolysis, toxic shock syndrome gene, and fibrinogen-binding protein gene, respectively. In addition, the virulence factors viz. sea; seb; sec encoding enterotoxins were detected in the DNA extracted from S. aureus B3 strain. Aqueous extract of Moringa oleifera seeds (MSE) showed inhibitory activity against S. aureus LC 554891 better than that obtained by tetracycline, essential oils or HB. Minimum inhibitory concentration (MIC) of MSE was 20µg/mL. Instrumental analysis of MSE showed 14 bioactive chemical compounds. Combinations of both MSE and tetracycline showed distinctive inhibitory activity against S. aureus LC 554891 than that obtained by either tetracycline or MSE singly.
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Antibacterianos/farmacologia , Moringa oleifera/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Fatores de VirulênciaRESUMO
BACKGROUND: There is controversial data in the literature about the characteristics and features of dual hepatitis B and hepatitis C infection. This work is concerned with estimating the extent to which HBV could influence circulating levels of hepatitis C viral nonstructural-4 (HCV-NS4) in addition to some direct fibrosis markers in chronic hepatitis C. METHODS: Thirty-eight HCV mono-infected and 87 HCV/HBV co-infected patients constituted this study. Western-blot and ELISA were used for identifying HCV-NS4, hepatitis B surface antigen (HBsAg), collagen III and matrixmetalloproteinase-1 (MMP-1) in patients' sera. RESULTS: Hepatitis B surface antigen (HBsAg) provided area under curve (AUC) of 0.97 for identifying HBV-patients with 89% sensitivity and 94% specificity, while HCV-NS4 antigen provided an AUC of 0.95 for identifying HCV-patients with 89% sensitivity and absolute specificity (100%). In general, patients with significant fibrosis (F2-F4) showed significantly higher concentration of collagen III (P = 0.009) and lower concentrations of MMP-1 (P = 0.007) when compared to patients with minimal fibrosis (F1). However, HCV/HBV co-infected patients with F1 and F2-F4 did not show any significant difference (P > 0.05) from HCV mono-infected patients with respect to HCV-NS4, collagen III and MMP-1. These results indicate that HBV does not influence the rate of HCV-NS4 synthesis and the deposition of extracellular matrix in HCV/HBV co-infected patients and subsequently does not affect the progression rates of hepatic fibrosis. CONCLUSION: HCV/HBV co-infected and HCV- mono-infected patients had similar clinical characteristics and there is no effect of HBV co-infection on the progression rates of liver fibrosis in chronic hepatitis C patients.
Assuntos
Coinfecção/sangue , Coinfecção/virologia , Colágeno Tipo III/sangue , Vírus da Hepatite B/fisiologia , Hepatite B/sangue , Hepatite C Crônica/sangue , Hepatite C Crônica/virologia , Metaloproteinase 1 da Matriz/sangue , Adulto , Biópsia , Feminino , Hepatite B/virologia , Humanos , Fígado/patologia , Cirrose Hepática/patologia , Masculino , Proteínas não Estruturais Virais/metabolismoRESUMO
BACKGROUND: Perinatal exposure to hepatitis C virus (HCV) antigens during pregnancy may affect the developing immune system in the fetus. We aimed to study the perinatal transmission of HCV structural and non-structural antigens. METHODS: Sera from 402 pregnant mothers were tested for anti-HCV antibody and HCV RNA. HCV antigens were determined in sera from 101 HCV-infected mothers and their cord blood. RESULTS: In both serum and cord blood samples, HCV NS4 (non-structural 4) at 27 kDa, E1 (envelope 1) at 38 kDa and E2 (envelope 2) at 40 kDa were identified, purified and quantified using western blotting, electroelution and ELISA. Maternal sera and neonate cord blood samples had similar detection rates for NS4 (94.1%), E1 (90.1%) and E2 (90.1%). The mean maternal serum levels (optical density, OD) of HCV NS4 (0.87 ± 0.01), E1 (0.86 ± 0.01) and E2 (0.85 ± 0.01) did not differ significantly (p > 0.05) from those of neonatal cord blood (0.83 ± 0.01, 0.87 ± 0.01 and 0.85 ± 0.01, respectively). Also, strong correlations (p < 0.0001) were shown between sera and cord blood sample levels of HCV NS4, r = 0.77; E1, r = 0.76 and E2, r = 0.80. The vertical transmission of these antigens in vaginal delivery did not differ significantly (p > 0.05) from those in caesarean section. CONCLUSIONS: These findings indicate that vertical transmission of HCV NS4, E1 and E2 antigens was very high. Thus, exposure to these antigens may influence the developing immune responses to natural infection or future vaccination.
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Hepacivirus/imunologia , Antígenos da Hepatite C/sangue , Hepatite C/transmissão , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez/virologia , Proteínas do Envelope Viral/sangue , Proteínas não Estruturais Virais/sangue , Adulto , Western Blotting , Feminino , Sangue Fetal/virologia , Hepacivirus/genética , Anticorpos Anti-Hepatite C/sangue , Antígenos da Hepatite C/líquido cefalorraquidiano , Humanos , Recém-Nascido , Gravidez , Proteínas do Envelope Viral/imunologia , Proteínas não Estruturais Virais/imunologiaRESUMO
BACKGROUND AND AIMS: Hepatitis C virus (HCV) has emerged as the major pathogen of liver disease worldwide. The aim of this study was to quantitate and evaluate the performance of HCV-NS4 antigen as an alternative approach for confirmation of viremia. METHODS: Detection of HCV-NS4 was assessed in 883 patients with chronic hepatitis C. Areas under the ROC curves (AUC) were used to assess and compare diagnostic accuracy of ELISA for HCV-NS4 with quantitative HCV-RNA as a gold standard. RESULTS: HCV-NS4 was identified at 27 kDa using Western blot. AUC for HCV-NS4 detection was 0.95 for all patients with different liver pathologies: 0.93 for liver fibrosis (LF), 0.95 for liver cirrhosis (LC) and 0.98 for hepatocellular carcinoma (HCC). The mean ± SD (µg/mL) of HCV-NS4 in LF was 94.2 ± 55.6; in LC was 99.3 ± 64.8 and in HCC was 124.9 ± 70.3. CONCLUSIONS: HCV-NS4 antigen detection using ELISA is a reliable test in the confirmation of HCV infection.
Assuntos
Antígenos da Hepatite C/análise , Hepatite C Crônica/diagnóstico , Hepatopatias/virologia , Proteínas não Estruturais Virais/análise , Adulto , Western Blotting , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/virologia , Egito , Ensaio de Imunoadsorção Enzimática , Feminino , Hepacivirus/imunologia , Hepacivirus/isolamento & purificação , Antígenos da Hepatite C/imunologia , Hepatite C Crônica/complicações , Hepatite C Crônica/imunologia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/imunologia , Cirrose Hepática/virologia , Hepatopatias/complicações , Hepatopatias/imunologia , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Proteínas não Estruturais Virais/imunologia , Viremia/complicações , Viremia/diagnóstico , Viremia/imunologia , Adulto JovemRESUMO
The association of kefir microbiota was observed by electron microscopic examination. Scanning electron microscopic (SEM) observations revealed that kefir grain surface is very rough and the inner portions had scattered irregular holes on its surface. The interior of the grain comprised fibrillar materials which were interpreted as protein, lipid and a soluble polysaccharide, the kefiran complex that surrounds yeast and bacteria in the grain. Yeast was observed more clearly than bacteria on the outer portion of the grain. Transmission electron microscopic (TEM) observations of kefir revealed that the grain comprised a mixed culture of yeast and bacteria growing in close association with each other. Microbiota is dominated by budded and long-flattened yeast cells growing together with lactobacilli and lactococci bacteria. Bacterial cells with rounded ends were also observed in this mixed culture. Kefir grains, kefir suspensions, and kefiran were tested for antimicrobial activities against several bacterial and fungal species. The highest activity was obtained against Streptococcus faecalis KR6 and Fusarium graminearum CZ1. Growth of Aspergillus flavus AH3 producing for aflatoxin B1 for 10 days in broth medium supplemented with varying concentrations of kefir filtrate (%, v/v) showed that sporulation was completely inhibited at the higher concentrations of kefir filtrate (7-10%, v/v). The average values of both mycelial dry weights and aflatoxin B1 were completely inhibited at 10% (v/v). This is the first in vitro study about the antifungal characteristics of kefir against filamentous fungi which was manifested by applying its inhibitory effect on the productivity of aflatoxin B1 by A. flavus AH3.