Evaluation of the Anti-Shigellosis Activity of Dietary Isothiocyanates in Galleria mellonella Larvae

Cruciferous vegetables, widely present in daily diets, are a rich source of organosulfur compounds with proven health benefits, especially chemopreventive or antioxidative effects. Isothiocyanate derivatives (ITCs) exhibit a broad spectrum of biological and pharmacological activity and recently, their antibacterial properties have been of particular importance. Here, we have focused on the anti-shigellosis activity of sulforaphane (SFN) and phenethyl ITC (PEITC). The genus Shigella causes gastroenteritis in humans, which constitutes a threat to public health. Production of a potent Stx toxin by S. dysenteriae type 1 results not only in more severe symptoms but also in serious sequela, including the hemolytic uremic syndrome. Here, we present evidence that two aliphatic and aromatic ITCs derivatives, SFN and PEITC, have an effective antibacterial potency against S. dysenteriae, also negatively regulating the stx gene expression. The molecular mechanism of this effect involves induction of the global stress-induced stringent response. ITCs also inhibit bacterial virulence against the Vero and HeLa cells. We present evidence for the therapeutic effect of sulforaphane and phenethyl ITC against a S. dysenteriae infection in the Galleria mellonella larvae model. Thus, our results indicate that isothiocyanates can be effectively used to combat dangerous bacterial infections.

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Antibacterial Properties of Organosulfur Compounds of Garlic (Allium sativum)

Frontiers in Microbiology ◽

10.3389/fmicb.2021.613077 ◽

2021 ◽

Vol 12 ◽

Author(s):

Sushma Bagde Bhatwalkar ◽

Rajesh Mondal ◽

Suresh Babu Naidu Krishna ◽

Jamila Khatoon Adam ◽

Patrick Govender ◽

...

Keyword(s):

Bacterial Infections ◽

Allium Sativum ◽

New Technologies ◽

Antibacterial Properties ◽

World Health ◽

Health Concern ◽

Organosulfur Compounds ◽

Wide Range ◽

The World ◽

Novel Antibiotics

Garlic (Allium sativum), a popular food spice and flavoring agent, has also been used traditionally to treat various ailments especially bacterial infections for centuries in various cultures around the world. The principal phytochemicals that exhibit antibacterial activity are oil-soluble organosulfur compounds that include allicin, ajoenes, and allyl sulfides. The organosulfur compounds of garlic exhibit a range of antibacterial properties such as bactericidal, antibiofilm, antitoxin, and anti-quorum sensing activity against a wide range of bacteria including multi-drug resistant (MDR) strains. The reactive organosulfur compounds form disulfide bonds with free sulfhydryl groups of enzymes and compromise the integrity of the bacterial membrane. The World Health Organization (WHO) has recognized the development of antibiotic resistance as a global health concern and emphasizes antibiotic stewardship along with the urgent need to develop novel antibiotics. Multiple antibacterial effects of organosulfur compounds provide an excellent framework to develop them into novel antibiotics. The review provides a focused and comprehensive portrait of the status of garlic and its compounds as antibacterial agents. In addition, the emerging role of new technologies to harness the potential of garlic as a novel antibacterial agent is discussed.

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Garlic Extract (Allium sativum L.) Effectively Inhibits Staphylococcus aureus and Escherichia coli by Invitro Test

Tropical Health and Medical Research ◽

10.35916/thmr.v0i0.22 ◽

2020 ◽

Vol 2 (2) ◽

pp. 61-68

Author(s):

Agnina Listya Anggraini ◽

Ratih Dewi Dwiyanti ◽

Anny Thuraidah

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Bacterial Infections ◽

Allium Sativum ◽

Antibacterial Properties ◽

Herbal Medicines ◽

Garlic Extract ◽

Dilution Method ◽

Initial Stage

Infection is a disease caused by the presence of pathogenic microbes, including Staphylococcus aureus and Escherichia coli. Garlic (Allium sativum L.) has chemical contents such as allicin, alkaloids, flavonoids, saponins, tannins, and steroids, which can function as an antibacterial against Staphylococcus aureus and Escherichia coli. This study aims to determine the antibacterial properties of garlic extract powder against Staphylococcus aureus and Escherichia coli. This research is the initial stage of the development of herbal medicines to treat Staphylococcus aureus and Escherichia coli infections. The antibacterial activity test was carried out by the liquid dilution method. The concentrations used were 30 mg/mL, 40 mg/mL, 50 mg/mL, 60 mg/mL and 70 mg/mL. The results showed that the Minimum Inhibitory Concentration (MIC) against Staphylococcus aureus and Escherichia coli was 40 mg/mL and 50 mg / mL. Minimum Bactericidal Concentration (MBC) results for Staphylococcus aureus and Escherichia coli are 50 mg/mL and 70 mg/mL. Based on the Simple Linear Regression test, the R2 value of Staphylococcus aureus and Escherichia coli is 0.545 and 0.785, so it can be concluded that there is an effect of garlic extract powder on the growth of Staphylococcus aureus and Escherichia coli by 54.5% and 78.5%. Garlic (Allium sativum L.) extract powder has potential as herbal medicine against bacterial infections but requires further research to determine its effect in vivo.

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Fluoroquinolone-3-carboxamide Amino Acid Conjugates: Synthesis, Antibacterial Properties And Molecular Modeling Studies

Medicinal Chemistry ◽

10.2174/1573406415666190904143852 ◽

2020 ◽

Vol 17 (1) ◽

pp. 71-84

Author(s):

Riham M. Bokhtia ◽

Siva S. Panda ◽

Adel S. Girgis ◽

Hitesh H. Honkanadavar ◽

Tarek S. Ibrahim ◽

...

Keyword(s):

Experimental Data ◽

Antibacterial Activity ◽

Amino Acid ◽

Bacterial Infections ◽

Antibacterial Agents ◽

Antibacterial Properties ◽

Computational Studies ◽

Protecting Group ◽

Amino Acid Conjugates ◽

Molecular Modeling Studies

Background: Bacterial infections are considered as one of the major global health threats, so it is very essential to design and develop new antibacterial agents to overcome the drawbacks of existing antibacterial agents. Method: The aim of this work is to synthesize a series of new fluoroquinolone-3-carboxamide amino acid conjugates by molecular hybridization. We utilized benzotriazole chemistry to synthesize the desired hybrid conjugates. Result: All the conjugates were synthesized in good yields, characterized, evaluated for their antibacterial activity. The compounds were screened for their antibacterial activity using methods adapted from the Clinical and Laboratory Standards Institute. Synthesized conjugates were tested for activity against medically relevant pathogens; Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27856) Staphylococcus aureus (ATCC 25923) and Enterococcus faecalis (ATCC 19433). Conclusion: The observed antibacterial experimental data indicates the selectivity of our synthesized conjugates against E.Coli. The protecting group on amino acids decreases the antibacterial activity. The synthesized conjugates are non-toxic to the normal cell lines. The experimental data were supported by computational studies.

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Au–ZnO Conjugated Black Phosphorus as a Near-Infrared Light-Triggering and Recurrence-Suppressing Nanoantibiotic Platform against Staphylococcus aureus

Pharmaceutics ◽

10.3390/pharmaceutics13010052 ◽

2021 ◽

Vol 13 (1) ◽

pp. 52

Author(s):

Atanu Naskar ◽

Sohee Lee ◽

Kwang-sun Kim

Keyword(s):

Staphylococcus Aureus ◽

Bacterial Infections ◽

Near Infrared ◽

Au Nanoparticles ◽

Synthesis Method ◽

Antibacterial Properties ◽

Black Phosphorus ◽

Infrared Light ◽

Resistant Bacteria ◽

Near Infrared Light

Antibiotic therapy is the gold standard for bacterial infections treatment. However, the rapid increase in multidrug-resistant (MDR) bacterial infections and its recent use for secondary bacterial infections in many COVID-19 patients has considerably weakened its treatment efficacy. These shortcomings motivated researchers to develop new antibacterial materials, such as nanoparticle-based antibacterial platform with the ability to increase the chances of killing MDR strains and prevent their drug resistance. Herein, we report a new black phosphorus (BP)-based non-damaging near-infrared light-responsive platform conjugated with ZnO and Au nanoparticles as a synergistic antibacterial agent against Staphylococcus aureus species. First, BP nanosheets containing Au nanoparticles were assembled in situ with the ZnO nanoparticles prepared by a low-temperature solution synthesis method. Subsequently, the antibacterial activities of the resulting Au–ZnO–BP nanocomposite against the non-resistant, methicillin-resistant, and erythromycin-resistant S. aureus species were determined, after its photothermal efficacy was assessed. The synthesized nanocomposite exhibited excellent anti-S. aureus activity and good photothermal characteristics. The non-resistant S. aureus species did not produce drug-resistant bacteria after the treatment of multiple consecutive passages under the pressure of the proposed nanoantibiotic, but rapidly developed resistance to erythromycin. This work clearly demonstrates the excellent photothermal antibacterial properties of Au–ZnO–BP nanocomposite against the MDR S. aureus species.

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Phage Resistance Is Associated with Decreased Virulence in KPC-Producing Klebsiella pneumoniae of the Clonal Group 258 Clade II Lineage

Microorganisms ◽

10.3390/microorganisms9040762 ◽

2021 ◽

Vol 9 (4) ◽

pp. 762

Author(s):

Lucia Henrici De Angelis ◽

Noemi Poerio ◽

Vincenzo Di Pilato ◽

Federica De Santis ◽

Alberto Antonelli ◽

...

Keyword(s):

Klebsiella Pneumoniae ◽

Parental Strain ◽

Bacterial Infections ◽

Capsular Polysaccharide ◽

Galleria Mellonella ◽

Bacterial Pathogen ◽

Phage Resistance ◽

Infection Model ◽

Lytic Phage ◽

Susceptible Host

Phage therapy is now reconsidered with interest in the treatment of bacterial infections. A major piece of information for this application is the definition of the molecular targets exploited by phages to infect bacteria. Here, the genetic basis of resistance to the lytic phage φBO1E by its susceptible host Klebsiella pneumoniae KKBO-1 has been investigated. KKBO-1 phage-resistant mutants were obtained by infection at high multiplicity. One mutant, designated BO-FR-1, was selected for subsequent experiments, including virulence assessment in a Galleria mellonella infection model and characterization by whole-genome sequencing. Infection with BO-FR-1 was associated with a significantly lower mortality when compared to that of the parental strain. The BO-FR-1 genome differed from KKBO-1 by a single nonsense mutation into the wbaP gene, which encodes a glycosyltransferase involved in the first step of the biosynthesis of the capsular polysaccharide (CPS). Phage susceptibility was restored when BO-FR-1 was complemented with the constitutive wbaP gene. Our results demonstrated that φBO1E infects KKBO-1 targeting the bacterial CPS. Interestingly, BO-FR-1 was less virulent than the parental strain, suggesting that in the context of the interplay among phage, bacterial pathogen and host, the emergence of phage resistance may be beneficial for the host.

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Designing P. aeruginosa synthetic phages with reduced genomes

Scientific Reports ◽

10.1038/s41598-021-81580-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Diana P. Pires ◽

Rodrigo Monteiro ◽

Dalila Mil-Homens ◽

Arsénio Fialho ◽

Timothy K. Lu ◽

...

Keyword(s):

Galleria Mellonella ◽

Antibacterial Properties ◽

Genetically Engineered ◽

In Vivo Studies ◽

Infection Model ◽

Promising Therapeutic Approach ◽

Genes Encoding ◽

First Time

AbstractIn the era where antibiotic resistance is considered one of the major worldwide concerns, bacteriophages have emerged as a promising therapeutic approach to deal with this problem. Genetically engineered bacteriophages can enable enhanced anti-bacterial functionalities, but require cloning additional genes into the phage genomes, which might be challenging due to the DNA encapsulation capacity of a phage. To tackle this issue, we designed and assembled for the first time synthetic phages with smaller genomes by knocking out up to 48% of the genes encoding hypothetical proteins from the genome of the newly isolated Pseudomonas aeruginosa phage vB_PaeP_PE3. The antibacterial efficacy of the wild-type and the synthetic phages was assessed in vitro as well as in vivo using a Galleria mellonella infection model. Overall, both in vitro and in vivo studies revealed that the knock-outs made in phage genome do not impair the antibacterial properties of the synthetic phages, indicating that this could be a good strategy to clear space from phage genomes in order to enable the introduction of other genes of interest that can potentiate the future treatment of P. aeruginosa infections.

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Interaction of Temporin-L Analogues with the E. coli FtsZ Protein

Antibiotics ◽

10.3390/antibiotics10060704 ◽

2021 ◽

Vol 10 (6) ◽

pp. 704

Author(s):

Angela Di Somma ◽

Carolina Canè ◽

Antonio Moretta ◽

Angela Duilio

Keyword(s):

Protein Interactions ◽

Bacterial Infections ◽

Antibacterial Properties ◽

Bacterial Cell Division ◽

Structural Determinants ◽

E Coli ◽

Functional Studies ◽

Division Process ◽

Z Ring ◽

Peptide Complexes

The research of new therapeutic agents to fight bacterial infections has recently focused on the investigation of antimicrobial peptides (AMPs), the most common weapon that all organisms produce to prevent invasion by external pathogens. Among AMPs, the amphibian Temporins constitute a well-known family with high antibacterial properties against Gram-positive and Gram-negative bacteria. In particular, Temporin-L was shown to affect bacterial cell division by inhibiting FtsZ, a tubulin-like protein involved in the crucial step of Z-ring formation at the beginning of the division process. As FtsZ represents a leading target for new antibacterial compounds, in this paper we investigated in detail the interaction of Temporin L with Escherichia coli FtsZ and designed two TL analogues in an attempt to increase peptide-protein interactions and to better understand the structural determinants leading to FtsZ inhibition. The results demonstrated that the TL analogues improved their binding to FtsZ, originating stable protein-peptide complexes. Functional studies showed that both peptides were endowed with a high capability of inhibiting both the enzymatic and polymerization activities of the protein. Moreover, the TL analogues were able to inhibit bacterial growth at low micromolar concentrations. These observations may open up the way to the development of novel peptide or peptidomimetic drugs tailored to bind FtsZ, hampering a crucial process of bacterial life that might be proposed for future pharmaceutical applications.

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Preparation and Performance Evaluation of Antibacterial Melt-Spun Polyurethane Fiber Loaded with Berberine Hydrochloride

Polymers ◽

10.3390/polym13142336 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2336

Author(s):

Ruifang Zhao ◽

Pengfei Tan ◽

Yanting Han ◽

Feng Yang ◽

Yidong Shi ◽

...

Keyword(s):

Antibacterial Agent ◽

Bacterial Infections ◽

Antibacterial Properties ◽

Coating Technology ◽

Daily Lives ◽

Berberine Hydrochloride ◽

Comprehensive Properties ◽

Melt Spun ◽

And Performance ◽

Application Prospects

(1) Background: Bacterial infections have long threatened global public safety; hence, it is significant to continuously develop antibacterial fibers that are closely related to people’s daily lives. Berberine hydrochloride is a natural antibacterial agent that has application prospects in the preparation of antibacterial fibers. (2) Methods: This study firstly verified the antibacterial properties of berberine hydrochloride and its possible antibacterial mechanism. Thereafter, berberine hydrochloride was introduced into the self-made melt-spun polyurethane fiber through optimized coating technology. The performance of coating modified polyurethane fiber has been systematically evaluated, including its antibacterial properties, mechanical properties, and surface wettability. (3) Results: Results show that the antibacterial polyurethane fiber with desirable comprehensive properties is expected to be used in the biomedical fields. (4) Conclusions: The research also provides a reference for the development and application of other natural antibacterial ingredients in fiber fields.

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Biosynthesis of CeO2 Nanoparticles Using Egg White and Their Antibacterial and Antibiofilm Properties on Clinical Isolates

Crystals ◽

10.3390/cryst11060584 ◽

2021 ◽

Vol 11 (6) ◽

pp. 584

Author(s):

Shalendra Kumar ◽

Faheem Ahmed ◽

Nagih M. Shaalan ◽

Osama Saber

Keyword(s):

Bacterial Infections ◽

Antibacterial Properties ◽

Spherical Shape ◽

Inhibition Zone ◽

Egg White ◽

Ceo2 Nanoparticles ◽

Inorganic Materials ◽

Ambient Conditions ◽

Uniform Size ◽

Tem Analysis

Bio-inspired synthesis is a novel and attractive environmentally friendly route to generating inorganic materials. In this work, the preparation of CeO2 NPs using egg white and investigation of their antibacterial properties both in liquid and solid growth medium against Escherichia coli and Staphylococcus aureus bacteria were reported. The CeO2 nanoparticles were characterized using X-ray diffraction (XRD), Field emission transmission electron microscope (FETEM), UV-Vis, Raman, and antibacterial measurements. The results from XRD and TEM analysis showed that the prepared nanoparticles were a single phase in the nano regime (5–7 nm) with spherical shape and uniform size distribution. Optical properties reflected the characteristics peaks of CeO2 in the UV-Vis range with a bandgap ~2.80 eV. The antibacterial activity of the synthesized NPs was achieved under ambient conditions with different bacteria and the results showed that the properties were different for both the bacteria. The highest activity with an inhibition zone of about 22 mm against S. aureus was obtained as compared with the 19 mm zone of inhibition obtained with E.coli. This finding will be of major significance that indicates a possibility to develop CeO2 NPs as antibacterial agents against extensive microorganisms to control and prevent the spread and persistence of bacterial infections.

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Curcumin: Modern Applications for a Versatile Additive

Coatings ◽

10.3390/coatings11050519 ◽

2021 ◽

Vol 11 (5) ◽

pp. 519

Author(s):

Florentina Monica Raduly ◽

Valentin Raditoiu ◽

Alina Raditoiu ◽

Violeta Purcar

Keyword(s):

Bacterial Infections ◽

Natural Compound ◽

Review Paper ◽

Curcuma Longa ◽

Antibacterial Properties ◽

Point Of View ◽

Nano Particles ◽

Synergistic Activity ◽

Quality Of Food

The recent development of several methods for extracting curcumin from the root of the plant Curcuma longa has led to intensified research on the properties of curcumin and its fields of application. Following the studies and the accreditation of curcumin as a natural compound with antifungal, antiviral, and antibacterial properties, new fields of application have been developed in two main directions—food and medical, respectively. This review paper aims to synthesize the fields of application of curcumin as an additive for the prevention of spoilage, safety, and quality of food. Simultaneously, it aims to present curcumin as an additive in products for the prevention of bacterial infections and health care. In both cases, the types of curcumin formulations in the form of (nano)emulsions, (nano)particles, or (nano)composites are presented, depending on the field and conditions of exploitation or their properties to be used. The diversity of composite materials that can be designed, depending on the purpose of use, leaves open the field of research on the conditioning of curcumin. Various biomaterials active from the antibacterial and antibiofilm point of view can be intuited in which curcumin acts as an additive that potentiates the activities of other compounds or has a synergistic activity with them.

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