scholarly journals Efficacy of Chelerythrine Against Mono- and Dual-Species Biofilms of Candida albicans and Staphylococcus aureus and Its Properties of Inducing Hypha-to-Yeast Transition of C. albicans

2020 ◽  
Vol 6 (2) ◽  
pp. 45 ◽  
Author(s):  
Weidong Qian ◽  
Jianing Zhang ◽  
Wenjing Wang ◽  
Miao Liu ◽  
Yuting Fu ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Candida Albicans ◽  
Laser Scanning ◽  
Fluorescent Dyes ◽  
Hyphal Growth ◽  
Antimicrobial Activities ◽  
Confocal Laser Scanning Microscope ◽  
Confocal Laser ◽  
Life Threatening ◽  
And Staphylococcus Aureus

Candida albicans and Staphylococcus aureus specifically often resulted in biofilm-associated diseases, ranging from superficial mucosal to life-threatening systemic infections. Recent studies reported that chelerythrine displayed antimicrobial activities against a few microorganisms, but its effects on mono- and dual-species biofilms of C. albicans and S. aureus have never been reported. The purpose of this study was to evaluate the efficacy of chelerythrine against mono- and dual-species biofilms, and explore its effect on the hyphal growth and the hypha-to-yeast transition of C. albicans. The results showed that minimum inhibitory concentrations (MICs) and minimum biofilm inhibitory concentration (MBIC90S) of chelerythrine against planktonic cells of mono-species were 4 and 2 μg/mL, while the MIC and MBIC90 were 6 and 3 μg/mL for dual-species. Meanwhile, the decrease in three matrix component levels and tolerance to antibiotics of biofilms formed by mono- and dual-species exposed to chelerythrine were confirmed by a confocal laser scanning microscope, in conjugation with five fluorescent dyes and a gatifloxacin diffusion assay. Moreover, C. albicans and S. aureus mono-species showed a 96.4, and 92.3% reduction, respectively, in 24-h preformed biofilm biomass in the presence of 128 µg/mL of chelerythrine. Similarly, preformed (24 h) dual-species biofilm biomass also displayed a significant reduction (90.7%) when treated with 192 μg/mL chelerythrine. Chelerythrine inhibited hyphae formation of C. albicans at 4 μg/mL, and C. albicans in hypha-form can be converted into yeast-form at 8 μg/mL of chelerythrine. Therefore, chelerythrine shows promise as a potential antimicrobial and antibiofilm agent for clinical effective treatments of mono- and mixed-species and/or biofilm-associated infections.

scholarly journals LHH1, a Novel Antimicrobial Peptide with Anti-Cancer Activity Identified from Lactobacillus casei HZ1

2020 ◽  
Author(s):  
Junfang He ◽  
Duxin Jin ◽  
Xuegang Luo ◽  
Tongcun Zhang
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Membrane ◽  
Lactobacillus Casei ◽  
Laser Scanning ◽  
Antimicrobial Activities ◽  
Confocal Laser Scanning Microscope ◽  
Confocal Laser ◽  
Beneficial Effects ◽  
Anti Cancer ◽  
Α Helix

Abstract Antimicrobial peptides have been attracting increasing attention for their multiple beneficial effects. In present study, a novel AMP with a molecular weight of 1875.25 Da, was identified from the genome of Lactobacillus casei HZ1. The peptide, which was named as LHH1 was comprised of 16 amino acid residues, and its α-helix content was 95.34% when dissolved in 30 mM SDS. LHH1 exhibited a broad range of antimicrobial activities against gram-positive bacteria and fungus. It could effectively inhibit staphylococcus aureus with a minimum inhibitory concentration of 3.5 μM and showed a low hemolytic activity. The scanning electron microscope, confocal laser scanning microscope and flow cytometry results showed that LHH1 exerted its antibacterial activity by damaging the cell membrane of staphylococcus aureus. Meanwhile, LHH1 also exhibited anti-cancer activities against several cancer cells including MGC803, HCT116 and C666-1 cells, and one major action of its anti-cancer mechanism was breaking the cell membrane.

scholarly journals Expansion of internal hyphal growth in Fusarium Head Blight infected grains contribute to the elevated mycotoxin production during the malting process

2021 ◽  
Author(s):  
Zhao Jin ◽  
Shyam Solanki ◽  
Gazala Ameen ◽  
Thomas Gross ◽  
Roshan Sharma Poudel ◽  
...  
Keyword(s):  
Fusarium Head Blight ◽  
Laser Scanning ◽  
Fungal Growth ◽  
Hyphal Growth ◽  
Confocal Laser Scanning Microscope ◽  
Confocal Laser ◽  
Aleurone Layer ◽  
Scanning Microscope ◽  
Head Blight ◽  
Trichothecene Mycotoxin

Fusarium head blight (FHB) and the occurrence of mycotoxins is the largest food safety threat to malting and brewing grains. Worldwide surveys of commercial beers have reported that the trichothecene mycotoxin deoxynivalenol (DON) is the most frequent contaminant in beer. Although the DON content of grain generally declines during steeping due to its solubilization, Fusarium can continue to grow and produce DON from steeping through the early kilning stage of malting. DON present on malt is largely extracted into beer. The objective of the current study was to localize the growth of Fusarium within FHB infected kernels by developing an improved method and to associate fungal growth with the production of DON during malting. FHB infected barley, wheat, rye, and triticale grains that exhibited large increases in the amount of Fusarium Tri5 DNA and trichothecene mycotoxins following malting were screened for hyphal localization. The growth of fungal hyphae associated with grain and malt was imaged by scanning electron microscope and confocal laser scanning microscope assisted with WGA-Alexa Fluor 488 staining, respectively. In barley, hyphae were present on or within the husk, vascular bundle, and pericarp cavities. Following malting, vast hyphal growth was observed not only in these regions, but also in the aleurone layer, endosperm, and embryo. Extensive fungal growth was also observed following malting of wheat, rye, and triticale. However, these grains already had an extensive internal presence of Fusarium hyphae in the unmalted grain, thus representing an enhanced chance of fungal expansion during the malting.

scholarly journals Plasma Treatment Effects on Oral Candida albicans Biofilms

2021 ◽  
pp. 1-7
Author(s):  
Qingsong Yu ◽  
Qing Hong ◽  
Xiaoqing Dong ◽  
Meng Chen ◽  
Hongmin Sun ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Plasma Treatment ◽  
Laser Scanning ◽  
Treatment Effects ◽  
Positive Control ◽  
Confocal Laser Scanning Microscope ◽  
Confocal Laser ◽  
Temperature Plasma ◽  
Promising Alternative ◽  
Candida Albicans Biofilms

The objective of this study is to evaluate the plasma treatment effects on oral fungal biofilms. Candida albicans biofilms were developed on the 48-well plate to serve as a model of oral fungal biofilm. The treatment of 0.2% chlorhexidine digluconate (CHX) was used as a positive control compared with plasma treatments. The efficacy of treatments was determined by 3-(4,5-dimethylazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and confocal laser scanning microscope (CLSM). The survival percentage of Candida albicans decreased from 52% to 27% as the plasma power increased from 6mA to 8mA and plasma exposure time extended from 2 min to 10 min. Moreover, it was found that there is a synergistic effect of the combination of plasma and CHX treatments. Scanning electron microscopy (SEM) examination indicated severe cell damages resulting from plasma treatment. In conclusion, the low-temperature plasma treatment is effective in deactivating Candida albicans biofilms and thus provides a promising alternative to disinfect oral fungal biofilms.

scholarly journals Sanguinarine Inhibits Mono- and Dual-Species Biofilm Formation by Candida albicans and Staphylococcus aureus and Induces Mature Hypha Transition of C. albicans

2020 ◽  
Vol 13 (1) ◽  
pp. 13 ◽  
Author(s):  
Weidong Qian ◽  
Wenjing Wang ◽  
Jianing Zhang ◽  
Miao Liu ◽  
Yuting Fu ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Laser Scanning ◽  
Inhibitory Concentration ◽  
Fluorescent Dyes ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Matrix Component ◽  
New Agents ◽  
Diffusion Assay ◽  
And Staphylococcus Aureus

Previous studies have reported that sanguinarine possesses inhibitory activities against several microorganisms, but its effects on mono- and dual-species biofilms of C. albicans and S. aureus have not been fully elucidated. In this study, we aimed to evaluate the efficacy of sanguinarine for mono- and dual-species biofilms and explore its ability to induce the hypha-to-yeast transition of C. albicans. The results showed that the minimum inhibitory concentration (MIC) and minimum biofilm inhibitory concentration (MBIC90) of sanguinarine against C. albicans and S. aureus mono-species biofilms was 4, and 2 μg/mL, respectively, while the MIC and MBIC90 of sanguinarine against dual-species biofilms was 8, and 4 μg/mL, respectively. The decrease in the levels of matrix component and tolerance to antibiotics of sanguinarine-treated mono- and dual-species biofilms was revealed by confocal laser scanning microscopy combined with fluorescent dyes, and the gatifloxacin diffusion assay, respectively. Meanwhile, sanguinarine at 128 and 256 μg/mL could efficiently eradicate the preformed 24-h biofilms by mono- and dual-species, respectively. Moreover, sanguinarine at 8 μg/mL could result in the transition of C. albicans from the mature hypha form to the unicellular yeast form. Hence, this study provides useful information for the development of new agents to combat mono- and dual-species biofilm-associated infections, caused by C. albicans and S. aureus.

scholarly journals Determining Optimal Fluorescent Agent Concentrations in Dental Adhesive Resins for Imaging the Tooth/Restoration Interface

2017 ◽  
Vol 23 (1) ◽  
pp. 122-130 ◽  
Author(s):  
Odair Bim Júnior ◽  
Marco A. Cebim ◽  
Maria T. Atta ◽  
Camila M. Machado ◽  
Luciana F. Francisconi-dos-Rios ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Fluorescent Dyes ◽  
Confocal Laser Scanning Microscope ◽  
Confocal Laser ◽  
Bonding Agents ◽  
Dental Adhesive ◽  
Photophysical Parameters ◽  
Interface Potential ◽  
Fluorescent Agent

AbstractFluorescent dyes like Rhodamine B (RB) have been used to identify the spatial distribution of adhesive restorative materials in the tooth/restoration interface. Potential effects of the addition of RB to dental adhesives were addressed in the past, but no further information is available on how to determine suitable concentrations of RB in these bonding agents for imaging in the confocal laser scanning microscope. This study provides systematical strategies for adding RB to viscous dental adhesive resins, focusing on the determination of the lowest range of dye concentrations necessary to achieve an acceptable image of the dentin/adhesive interface. It was demonstrated that optimized images of the resin distribution in dentin can be produced with 0.1–0.02 mg/mL of RB in the (tested) adhesives. Our approaches took into account aspects related to the dye concentration, photophysical parameters in different host media, specimen composition and morphology to develop a rational use of the fluorescent agent with the resin-based materials. Information gained from this work can help optimize labeling methods using dispersions of low-molecular-weight dyes in different monomer blend systems.

scholarly journals LHH1, a novel antimicrobial peptide with anti-cancer cell activity identified from Lactobacillus casei HZ1

AMB Express ◽  
2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jun-Fang He ◽  
Du-Xin Jin ◽  
Xue-Gang Luo ◽  
Tong-Cun Zhang
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Membrane ◽  
Cancer Cells ◽  
Cancer Cell ◽  
Lactobacillus Casei ◽  
Laser Scanning ◽  
Cell Activity ◽  
Antimicrobial Activities ◽  
Confocal Laser ◽  
Anti Cancer

Abstract Antimicrobial peptides have been attracting increasing attention for their multiple beneficial effects. In present study, a novel AMP with a molecular weight of 1875.5 Da, was identified from the genome of Lactobacillus casei HZ1. The peptide, which was named as LHH1 was comprised of 16 amino acid residues, and its α-helix content was 95.34% when dissolved in 30 mM SDS. LHH1 exhibited a broad range of antimicrobial activities against Gram-positive bacteria and fungus. It could effectively inhibit Staphylococcus aureus with a minimum inhibitory concentration of 3.5 μM and showed a low hemolytic activity. The scanning electron microscope, confocal laser scanning microscope and flow cytometry results showed that LHH1 exerted its antibacterial activity by damaging the cell membrane of Staphylococcus aureus. Meanwhile, LHH1 also exhibited anti-cancer cell activities against several cancer cells via breaking the cell membrane of MGC803, HCT116 and C666-1 cancer cells.

scholarly journals Antibiofilm Activity of Antarctic Sponge-Associated Bacteria against Pseudomonas aeruginosa and Staphylococcus aureus

2021 ◽  
Vol 9 (3) ◽  
pp. 243
Author(s):  
Carmen Rizzo ◽  
Vincenzo Zammuto ◽  
Angelina Lo Giudice ◽  
Maria Giovanna Rizzo ◽  
Antonio Spanò ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Laser Scanning ◽  
Model Organisms ◽  
Confocal Laser ◽  
Antibiofilm Activity ◽  
Associated Bacteria ◽  
Crude Extracts ◽  
Sponge Associated Bacteria ◽  
And Staphylococcus Aureus

Bioprospecting in unusual marine environments provides an innovative approach to search novel biomolecules with antibiofilm activity. Antarctic sponge-associated bacteria belonging to Colwellia, Pseudoalteromonas, Shewanella and Winogradskyella genera were evaluated for their ability to contrast the biofilm formation by Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 29213, as model organisms. All strains were able to produce biofilm at both 4 and 25 °C, with the highest production being for Colwellia, Shewanella and Winogradskyella strains at 4 °C after 24 h. Antibiofilm activity of cell-free supernatants (CFSs) differed among strains and on the basis of their incubation temperature (CFSs4°C and CFSs25°C). The major activity was observed by CFSs4°C against S. aureus and CFSs25°C against P. aeruginosa, without demonstrating a bactericidal effect on their growth. Furthermore, the antibiofilm activity of crude extracts from Colwellia sp. GW185, Shewanella sp. CAL606, and Winogradskyella sp. CAL396 was also evaluated and visualized by confocal laser scanning microscopic images. Results based on the surface-coating assay and surface tension measurements suggest that CFSs and the crude extracts may act as biosurfactants inhibiting the first adhesion of P. aeruginosa and S. aureus. The CFSs and the novel biopolymers may be useful in applicative perspectives for pharmaceutical and environmental purposes.

scholarly journals Antibiofilm Activity on Candida albicans and Mechanism of Action on Biomembrane Models of the Antimicrobial Peptide Ctn[15–34]

2020 ◽  
Vol 21 (21) ◽  
pp. 8339
Author(s):  
Francisca Lidiane Linhares de Aguiar ◽  
Nuno C. Santos ◽  
Carolina Sidrim de Paula Cavalcante ◽  
David Andreu ◽  
Gandhi Radis Baptista ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Antimicrobial Peptide ◽  
Mechanism Of Action ◽  
Laser Scanning ◽  
Fluorescent Dyes ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Antibiofilm Activity ◽  
Membrane Composition ◽  
Fungal Cell

Ctn[15–34], the C-terminal fragment of crotalicidin, an antimicrobial peptide from the South American rattlesnake Crotalus durissus terrificus venom, displays remarkable anti-infective and anti-proliferative activities. Herein, its activity on Candida albicans biofilms and its interaction with the cytoplasmic membrane of the fungal cell and with a biomembrane model in vitro was investigated. A standard C. albicans strain and a fluconazole-resistant clinical isolate were exposed to the peptide at its minimum inhibitory concentration (MIC) (10 µM) and up to 100 × MIC to inhibit biofilm formation and its eradication. A viability test using XTT and fluorescent dyes, confocal laser scanning microscopy, and atomic force microscopy (AFM) were used to observe the antibiofilm effect. To evaluate the importance of membrane composition on Ctn[15–34] activity, C. albicans protoplasts were also tested. Fluorescence assays using di-8-ANEPPS, dynamic light scattering, and zeta potential measurements using liposomes, protoplasts, and C. albicans cells indicated a direct mechanism of action that was dependent on membrane interaction and disruption. Overall, Ctn[15–34] showed to be an effective antifungal peptide, displaying antibiofilm activity and, importantly, interacting with and disrupting fungal plasma membrane.

scholarly journals New Isocoumarin Analogues from the Marine-Derived Fungus Paraphoma sp. CUGBMF180003

Marine Drugs ◽  
2021 ◽  
Vol 19 (6) ◽  
pp. 313
Author(s):  
Xiuli Xu ◽  
Jiangpeng Li ◽  
Kai Zhang ◽  
Shangzhu Wei ◽  
Rui Lin ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Candida Albicans ◽  
Secondary Metabolites ◽  
Spectroscopic Data ◽  
2D Nmr ◽  
Antimicrobial Activities ◽  
Chemical Structures ◽  
Nmr Techniques ◽  
And Staphylococcus Aureus

Nine new secondary metabolites, including six isocoumarin analogues, 7-hydroxyoospolactone (1), 7-methoxyoospolactone (2), 7-methoxy-9-hydroxyoospolactone (3), 10-acetoxy-9-hydroxyoospolactone (4), 6-dehydroxysescandelin (5), parapholactone (6), and three compounds with a rare skeleton of isocoumarin coupled with phenylethylamine, namely paraphamide A (12), paraphamide B (13), and paraphamide C (14), together with five known compounds, oospolactone (7), 8-O-methyloospolactone (8), 10-hydroxyoospolactone (9), 9,10-dihydroxyoospolactone (10), and oospoglycol (11), were isolated and identified from the marine-derived fungus Paraphoma sp. CUGBMF180003. Their chemical structures were determined using spectroscopic data, including HRESIMS and 1D and 2D NMR techniques. Furthermore, the stereogenic carbons in 5 and 14 were determined by comparing the experimental and calculated electronic circular dichroism (ECD) spectra. The carbon skeleton of 12–14 was identified as the first example of isocoumarin coupled with phenylethylamine derivatives. All of these compounds were examined for antimicrobial activities against Candida albicans and Staphylococcus aureus. Both 1 and 6 showed antibacterial activity against S. aureus with MIC values of 12.5 μg/mL.

scholarly journals Interactions in the Tomato Rhizosphere of Two Pseudomonas Biocontrol Strains with the Phytopathogenic Fungus Fusarium oxysporum f. sp. radicis-lycopersici

2003 ◽  
Vol 16 (11) ◽  
pp. 983-993 ◽  
Author(s):  
Annouschka Bolwerk ◽  
Anastasia L. Lagopodi ◽  
André H. M. Wijfjes ◽  
Gerda E. M. Lamers ◽  
Thomas F. C. Chin-A-Woeng ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Laser Scanning ◽  
Hyphal Growth ◽  
Confocal Laser Scanning Microscope ◽  
Systemic Resistance ◽  
Phytopathogenic Fungus ◽  
Confocal Laser ◽  
Bacterial Strains ◽  
Tomato Root ◽  
Biocontrol Bacteria

The fungus Fusarium oxysporum f. sp. radicis-lycopersici causes foot and root rot of tomato plants, which can be controlled by the bacteria Pseudomonas fluorescens WCS365 and P. chlororaphis PCL1391. Induced systemic resistance is thought to be involved in biocontrol by P. fluorescens WCS365. The antifungal metabolite phenazine-1-carbox-amide (PCN), as well as efficient root colonization, are essential in the mechanism of biocontrol by P. chlororaphis PCL1391. To understand the effects of bacterial strains WCS365 and PCL1391 on the fungus in the tomato rhizosphere, microscopic analyses were performed using different autofluorescent proteins as markers. Tomato seedlings were inoculated with biocontrol bacteria and planted in an F. oxysporum f. sp. radicis-lycopersici-infested gnotobiotic sand system. Confocal laser scanning microscope analyses of the interactions in the tomato rhizosphere revealed that i) the microbes effectively compete for the same niche, and presumably also for root exudate nutrients; ii) the presence of either of the two bacteria negatively affects infection of the tomato root by the fungus; iii) both biocontrol bacteria colonize the hyphae extensively, which may represent a new mechanism in biocontrol by these pseudomonads; and iv) the production of PCN by P. chlororaphis PCL1391 negatively affects hyphal growth and branching, which presumably affects the colonization and infecting ability of the fungus.

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