Imidazole-Thiosemicarbazide Derivatives as Potent Anti-Mycobacterium tuberculosis Compounds with Antibiofilm Activity

Mycobacterium tuberculosis (Mtb) is an intracellular pathogenic bacterium and the causative agent of tuberculosis. This disease is one of the most ancient and deadliest bacterial infections, as it poses major health, social and economic challenges at a global level, primarily in low- and middle-income countries. The lack of an effective vaccine, the long and expensive drug therapy, and the rapid spread of drug-resistant strains of Mtb have led to the re-emergence of tuberculosis as a global pandemic. Here, we assessed the in vitro activity of new imidazole-thiosemicarbazide derivatives (ITDs) against Mtb infection and their effects on mycobacterial biofilm formation. Cytotoxicity studies of the new compounds in cell lines and human monocyte-derived macrophages (MDMs) were performed. The anti-Mtb activity of ITDs was evaluated by determining minimal inhibitory concentrations of resazurin, time-kill curves, bacterial intracellular growth and the effect on biofilm formation. Mutation frequency and whole-genome sequencing of mutants that were resistant to ITDs were performed. The antimycobacterial potential of ITDs with the ability to penetrate Mtb-infected human macrophages and significantly inhibit the intracellular growth of tubercle bacilli and suppress Mtb biofilm formation was observed.

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Safety profile, antimicrobial and antibiofilm activities of a nanostructured lipid carrier containing oil and butter from Astrocaryum vulgare: in vitro studies

International Journal for Innovation Education and Research ◽

10.31686/ijier.vol9.iss5.3113 ◽

2021 ◽

Vol 9 (5) ◽

pp. 478-497

Author(s):

Aline Rossato ◽

Larissa da Silva Silveira ◽

Pâmella Scharamm Oliveira ◽

Thobias Toniolo de Souza ◽

Ana Paula Becker ◽

...

Keyword(s):

Cell Viability ◽

Bacterial Infections ◽

Average Particle Size ◽

Aqueous Solubility ◽

Human Erythrocytes ◽

Antibiofilm Activity ◽

Average Particle ◽

Nanostructured Lipid Carrier ◽

Cytotoxicity Studies

Ethnopharmacological relevance: Tucumã (Astrocaryum vulgare)is a fruit native to the Amazon region. Extracts from the peel and pulp are thought of as promising treatments for bacterial infections. The primary constituents of Tucumã oil and butter possess unsaturated carbon chains that are susceptible to oxidation by light or heat. The oils have high volatility and low aqueous solubility that limits their use without a vehicle. Nanotechnology refers to techniques to solve these problems. Nanostructured lipid carriers (NLC), for example, protect fixed oils degradation by heat or light, as well as from oxidation and evaporation, ensuring greater stability and function, thereby prolonging the useful life of the final product. Study objectives: The objective of this study was to evaluate the hemolytic, cytotoxic, antimicrobial and antibiofilm properties of an NLC containing Tucumã butter and oil soasto improve the solubility and photosensitivity of the compounds, generating better pharmacological efficacy. Materials and methods: The NLC was assessed for stability for 60 days. The cytotoxicity of nanoparticles in peripheral blood mononucleated cells was determined in culture using assays for cell viability, DNA damage, oxidative metabolism and damage to human erythrocytes. Antimicrobial activity was determined using the broth microdilution technique and antibiofilm activity according to standardized protocols. Results: The Tucumã NLC remained stable throughout the evaluated period, with pH between 5.22–5.35, monodisperse distribution (PDI<0.3) and average particle size of 170.7 ± 3nm. Cytotoxicity studies revealed that the NLC is safe and modulates inflammatory processes, demonstrated by increased cell viability and nitric oxide levels. There was low hemolytic activity of the NLC against human erythrocytes almost concentrations tested. Conclusion: Taken together, the data suggest that NLC containing Tucumã oil and butter showed antimicrobial and antibiofilm activity against organisms that cause morbidity and mortality in humans. They may be alternative solutions to public health problems related to bacterial infections.

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Biofilm formation in the lung contributes to virulence and drug tolerance of Mycobacterium tuberculosis

Nature Communications ◽

10.1038/s41467-021-21748-6 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Poushali Chakraborty ◽

Sapna Bajeli ◽

Deepak Kaushal ◽

Bishan Dass Radotra ◽

Ashwani Kumar

Keyword(s):

Mycobacterium Tuberculosis ◽

Immune System ◽

Biofilm Formation ◽

Antimycobacterial Activity ◽

Drug Tolerance ◽

Host Immune System ◽

Tissue Sections ◽

Slow Growing

AbstractTuberculosis is a chronic disease that displays several features commonly associated with biofilm-associated infections: immune system evasion, antibiotic treatment failures, and recurrence of infection. However, although Mycobacterium tuberculosis (Mtb) can form cellulose-containing biofilms in vitro, it remains unclear whether biofilms are formed during infection in vivo. Here, we demonstrate the formation of Mtb biofilms in animal models of infection and in patients, and that biofilm formation can contribute to drug tolerance. First, we show that cellulose is also a structural component of the extracellular matrix of in vitro biofilms of fast and slow-growing nontuberculous mycobacteria. Then, we use cellulose as a biomarker to detect Mtb biofilms in the lungs of experimentally infected mice and non-human primates, as well as in lung tissue sections obtained from patients with tuberculosis. Mtb strains defective in biofilm formation are attenuated for survival in mice, suggesting that biofilms protect bacilli from the host immune system. Furthermore, the administration of nebulized cellulase enhances the antimycobacterial activity of isoniazid and rifampicin in infected mice, supporting a role for biofilms in phenotypic drug tolerance. Our findings thus indicate that Mtb biofilms are relevant to human tuberculosis.

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Antimicrobial and Antibiofilm Activity against Staphylococcus aureus of Opuntia ficus-indica (L.) Mill. Cladode Polyphenolic Extracts

Antioxidants ◽

10.3390/antiox8050117 ◽

2019 ◽

Vol 8 (5) ◽

pp. 117 ◽

Cited By ~ 17

Author(s):

Federica Blando ◽

Rossella Russo ◽

Carmine Negro ◽

Luigi De Bellis ◽

Stefania Frassinetti

Keyword(s):

Staphylococcus Aureus ◽

Antioxidant Activity ◽

Antioxidant Capacity ◽

Biofilm Formation ◽

Ex Vivo ◽

Trolox Equivalent Antioxidant Capacity ◽

Total Phenolic ◽

Antibiofilm Activity ◽

Opuntia Ficus Indica

Plant extracts are a rich source of natural compounds with antimicrobial properties, which are able to prevent, at some extent, the growth of foodborne pathogens. The aim of this study was to investigate the potential of polyphenolic extracts from cladodes of Opuntia ficus-indica (L.) Mill. to inhibit the growth of some enterobacteria and the biofilm formation by Staphylococcus aureus. Opuntia ficus-indica cladodes at two stages of development were analysed for total phenolic content and antioxidant activity by Oxygen Radical Absorbance Capacity (ORAC) and Trolox equivalent antioxidant capacity (TEAC) (in vitro assays) and by cellular antioxidant activity in red blood cells (CAA-RBC) (ex vivo assay). The Liquid Chromatography Time-of-Flight Mass Spectrometry (LC/MS–TOF) analysis of the polyphenolic extracts revealed high levels of piscidic acid, eucomic acid, isorhamnetin derivatives and rutin, particularly in the immature cladode extracts. Opuntia cladodes extracts showed a remarkable antioxidant activity (in vitro and ex vivo), a selective inhibition of the growth of Gram-positive bacteria, and an inhibition of Staphylococcus aureus biofilm formation. Our results suggest and confirm that Opuntia ficus-indica cladode extracts could be employed as functional food, due to the high polyphenolic content and antioxidant capacity, and used as natural additive for food process control and food safety.

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Blue laser light inhibits biofilm formation in vitro and in vivo by inducing oxidative stress

npj Biofilms and Microbiomes ◽

10.1038/s41522-019-0102-9 ◽

2019 ◽

Vol 5 (1) ◽

Cited By ~ 10

Author(s):

Katia Rupel ◽

Luisa Zupin ◽

Giulia Ottaviani ◽

Iris Bertani ◽

Valentina Martinelli ◽

...

Keyword(s):

Oxidative Stress ◽

Biofilm Formation ◽

Mammalian Cells ◽

Bacterial Infections ◽

Laser Light ◽

Therapeutic Potential ◽

Blue Laser ◽

Data Set

Abstract Resolution of bacterial infections is often hampered by both resistance to conventional antibiotic therapy and hiding of bacterial cells inside biofilms, warranting the development of innovative therapeutic strategies. Here, we report the efficacy of blue laser light in eradicating Pseudomonas aeruginosa cells, grown in planktonic state, agar plates and mature biofilms, both in vitro and in vivo, with minimal toxicity to mammalian cells and tissues. Results obtained using knock-out mutants point to oxidative stress as a relevant mechanism by which blue laser light exerts its anti-microbial effect. Finally, the therapeutic potential is confirmed in a mouse model of skin wound infection. Collectively, these data set blue laser phototherapy as an innovative approach to inhibit bacterial growth and biofilm formation, and thus as a realistic treatment option for superinfected wounds.

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Phage φAB6-Borne Depolymerase Combats Acinetobacter baumannii Biofilm Formation and Infection

Antibiotics ◽

10.3390/antibiotics10030279 ◽

2021 ◽

Vol 10 (3) ◽

pp. 279

Author(s):

Md. Shahed-Al-Mahmud ◽

Rakesh Roy ◽

Febri Gunawan Sugiokto ◽

Md. Nazmul Islam ◽

Ming-Der Lin ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Biofilm Formation ◽

Bacterial Infections ◽

Capsular Polysaccharide ◽

Foley Catheter ◽

Inhibition Zone ◽

Control Group ◽

Bacterial Cells ◽

Bacterial Lawn

Biofilm formation is one of the main causes of increased antibiotic resistance in Acinetobacter baumannii infections. Bacteriophages and their derivatives, such as tail proteins with depolymerase activity, have shown considerable potential as antibacterial or antivirulence agents against bacterial infections. Here, we gained insights into the activity of a capsular polysaccharide (CPS) depolymerase, derived from the tailspike protein (TSP) of φAB6 phage, to degrade A. baumannii biofilm in vitro. Recombinant TSP showed enzymatic activity and was able to significantly inhibit biofilm formation and degrade formed biofilms; as low as 0.78 ng, the inhibition zone can still be formed on the bacterial lawn. Additionally, TSP inhibited the colonization of A. baumannii on the surface of Foley catheter sections, indicating that it can be used to prevent the adhesion of A. baumannii to medical device surfaces. Transmission and scanning electron microscopy demonstrated membrane leakage of bacterial cells treated with TSP, resulting in cell death. The therapeutic effect of TSP in zebrafish was also evaluated and the results showed that the survival rate was significantly improved (80%) compared with that of the untreated control group (10%). Altogether, we show that TSP derived from φAB6 is expected to become a new antibiotic against multi-drug resistant A. baumannii and a biocontrol agent that prevents the formation of biofilms on medical devices.

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Inhibitory Effects of Lactoferrin on Growth and Biofilm Formation of Porphyromonas gingivalis and Prevotella intermedia

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01688-08 ◽

2009 ◽

Vol 53 (8) ◽

pp. 3308-3316 ◽

Cited By ~ 72

Author(s):

Hiroyuki Wakabayashi ◽

Koji Yamauchi ◽

Tetsuo Kobayashi ◽

Tomoko Yaeshima ◽

Keiji Iwatsuki ◽

...

Keyword(s):

Porphyromonas Gingivalis ◽

Biofilm Formation ◽

Periodontal Diseases ◽

Antimicrobial Protein ◽

Antibiofilm Activity ◽

Prevotella Intermedia ◽

Periodontopathic Bacteria ◽

Oral Pathogens ◽

In Vitro Effects

ABSTRACT Lactoferrin (LF) is an iron-binding antimicrobial protein present in saliva and gingival crevicular fluids, and it is possibly associated with host defense against oral pathogens, including periodontopathic bacteria. In the present study, we evaluated the in vitro effects of LF-related agents on the growth and biofilm formation of two periodontopathic bacteria, Porphyromonas gingivalis and Prevotella intermedia, which reside as biofilms in the subgingival plaque. The planktonic growth of P. gingivalis and P. intermedia was suppressed for up to 5 h by incubation with ≥130 μg/ml of human LF (hLF), iron-free and iron-saturated bovine LF (apo-bLF and holo-bLF, respectively), and ≥6 μg/ml of bLF-derived antimicrobial peptide lactoferricin B (LFcin B); but those effects were weak after 8 h. The biofilm formation of P. gingivalis and P. intermedia over 24 h was effectively inhibited by lower concentrations (≥8 μg/ml) of various iron-bound forms (the apo, native, and holo forms) of bLF and hLF but not LFcin B. A preformed biofilm of P. gingivalis and P. intermedia was also reduced by incubation with various iron-bound bLFs, hLF, and LFcin B for 5 h. In an examination of the effectiveness of native bLF when it was used in combination with four antibiotics, it was found that treatment with ciprofloxacin, clarithromycin, and minocycline in combination with native bLF for 24 h reduced the amount of a preformed biofilm of P. gingivalis compared with the level of reduction achieved with each agent alone. These results demonstrate the antibiofilm activity of LF with lower iron dependency against P. gingivalis and P. intermedia and the potential usefulness of LF for the prevention and treatment of periodontal diseases and as adjunct therapy for periodontal diseases.

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The Anti-biofilm Activity of Nanometric Zinc doped Bioactive Glass against Putative Periodontal Pathogens: An in vitro Study

Biomedical glasses ◽

10.1515/bglass-2018-0009 ◽

2018 ◽

Vol 4 (1) ◽

pp. 95-107

Author(s):

Nasrin Esfahanizadeh ◽

Mohammad Reza Nourani ◽

Abbas Bahador ◽

Nasrin Akhondi ◽

Mostafa Montazeri

Keyword(s):

Biofilm Formation ◽

Sol Gel ◽

Antimicrobial Properties ◽

In Vitro Study ◽

Inhibitory Effect ◽

Antibiofilm Activity ◽

Periodontal Pathogens ◽

Microplate Reader ◽

45S5 Bioglass

Abstract Colonization of periodontal pathogens on the surgical sites is one of the primary reasons for the failure of regenerative periodontal therapies. Bioactive glasses (BGs) owing to their favorable structural and antimicrobial properties have been proposed as promising materials for the reconstruction of periodontal and peri-implant bone defects. This study aimed to investigate the antibiofilm activity of zinc-doped BG (Zn/BG) compared with 45S5 Bioglass® (BG®) on putative periodontal pathogens. In this in vitro experimental study, the nano BG doped with 5-mol% zinc and BG® were synthesized by sol-gel method. Mono-species biofilms of Aggregatibacter actinomycetemcomitans (A. a), Porphyromonas gingivalis (P. g), and Prevotella intermedia (P. i)were prepared separately in a well-containing microplate. After 48 hours of exposure to generated materials at 37°C, the anti-biofilm potential of the samples was studied by measuring the optical density (OD) at 570nm wavelengths with a microplate reader. Two-way ANOVA then analyzed the results. Both Zn/BG and BG® significantly reduced the biofilm formation ability of all examined strains after 48 hours of incubation (P=0.0001). Moreover, the anti-biofilm activity of Zn/BG was significantly stronger than BG® (P=0.0001), which resulted in the formation of a weak biofilm (OD<1) compared with a moderately adhered biofilm observed with BG® (1<OD<2). Zn/BG showed a significant inhibitory effect on the biofilm formation of all examined periodontal pathogens. Given the enhanced regenerative and anti-biofilm properties of this novel biomaterial, further investigations are required for its implementation in clinical situations.

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In vitro Antibiofilm Activity of Pomegranate (Punica granatum) Juice on Oral Pathogens

Journal of Indonesian Dental Association ◽

10.32793/jida.v1i2.353 ◽

2019 ◽

Vol 1 (2) ◽

pp. 49

Author(s):

Jemima Pramadita ◽

Armelia Sari Widyarman

Keyword(s):

Biofilm Formation ◽

Brain Heart Infusion ◽

Punica Granatum ◽

Pomegranate Juice ◽

Bacterial Suspension ◽

Antibiofilm Activity ◽

Microplate Reader ◽

Level Of Significance ◽

Negative Controls

Introduction: Pomegranate (Punica granatum) fruit contains valuable ingredients, such as ellagitannins and flavonoids, that have many potential effects, including antibacterial, antifungal, and anti-inflammatory functions. Objectives: The aim of this study was to investigate the effects of pomegranate fruit juice on F. nucleatum and S. sanguinis monospecies and multispecies biofilm formation in vitro. Methods: Pomegranate juice was obtained using a juicer and diluted using a brain heart infusion (BHI) broth into five different concentrations. The biofilm assay was performed as follows: F. nucleatum and S. sanguinis were cultured separately in the BHI broth for 48 hours at 37°C in an anaerobic atmosphere. A 200 mL bacterial suspension (107 CFU/mL) was distributed into a 96-well plate and incubated for 24 hours to form a biofilm. Subsequently, pomegranate juice was added to the biofilm well and observed after 1 hours, 3 hours, 6 hours, and 24 hours. The biofilm mass was measured using a microplate reader (490 nm) after crystal violet staining. Chlorhexidine (0.2%) and the biofilms without treatment were used as the positive and negative controls, respectively. The data were statistically analyzed using one-way analysis of variance, with p<0.05 as the level of significance. Result: There was a significant biofilm reduction after treatment with pomegranate juice for all the concentrations and incubation times (p<0.05). The effective concentrations to inhibit the biofilm monospecies F. nucleatum and S. sanguinis and the multispecies were 6.25% (OD 0.148±0.019), 50% (OD 0.211±0.026), and 6.25% (OD 0.024±0.209), respectively. Conclusion: Pomegranate juice inhibits F. nucleatum and S. sanguinis biofilm formation as a monospecies and a multispecies. Future studies are needed to observe the mechanism of this active substance.

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Chlorpromazine-impregnated catheters as a potential strategy to control biofilm-associated urinary tract infections

Future Microbiology ◽

10.2217/fmb-2019-0092 ◽

2019 ◽

Vol 14 (12) ◽

pp. 1023-1034 ◽

Cited By ~ 3

Author(s):

José JC Sidrim ◽

Bruno R Amando ◽

Francisco IF Gomes ◽

Marilia SMG do Amaral ◽

Paulo CP de Sousa ◽

...

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Klebsiella Pneumoniae ◽

Urinary Tract Infections ◽

Proteus Mirabilis ◽

Biofilm Formation ◽

Antibiofilm Activity ◽

Potential Strategy ◽

Tract Infections

Aim: This study proposes the impregnation of Foley catheters with chlorpromazine (CPZ) to control biofilm formation by Escherichia coli, Proteus mirabilis and Klebsiella pneumoniae. Materials & methods: The minimum inhibitory concentrations (MICs) for CPZ and the effect of CPZ on biofilm formation were assessed. Afterward, biofilm formation and the effect of ciprofloxacin and meropenem (at MIC) on mature biofilms grown on CPZ-impregnated catheters were evaluated. Results: CPZ MIC range was 39.06–625 mg/l. CPZ significantly reduced (p < 0.05) biofilm formation in vitro and on impregnated catheters. In addition, CPZ-impregnation potentiated the antibiofilm activity of ciprofloxacin and meropenem. Conclusion: These findings bring perspectives for the use of CPZ as an adjuvant for preventing and treating catheter-associated urinary tract infections.

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Glutathione and Nitrosoglutathione in Macrophage Defense against Mycobacterium tuberculosis

Infection and Immunity ◽

10.1128/iai.73.3.1886-1889.2005 ◽

2005 ◽

Vol 73 (3) ◽

pp. 1886-1889 ◽

Cited By ~ 54

Author(s):

Vishwanath Venketaraman ◽

Yaswant K. Dayaram ◽

Meliza T. Talaue ◽

Nancy D. Connell

Keyword(s):

Mycobacterium Tuberculosis ◽

Intracellular Growth

ABSTRACT We demonstrate that Mycobacterium tuberculosis grown in vitro is sensitive to glutathione and its derivative S-nitrosoglutathione. Furthermore, our infection studies with J774.1 macrophages indicate that glutathione is essential for the control of the intracellular growth of M. tuberculosis. This study indicates the important role of glutathione in the control of macrophages by M. tuberculosis.

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