The role of structure and molecular properties of terpenoids in determining their antimicrobial activity

Microbes are considered as the primary etiologic agents in endodontic diseases.Disinfection of the root canal is obtained by the combined effect of biomechanicalpreparation, irrigation and intra canal medicament. The aim of the present study wasto assess the antimicrobial activity of intracanal medicaments (formocresol andEndosepton) against two micro organisms (Streptococcus mutans and staphylococcusaureus) isolated from 15 necrotic pulps of primary molars indicated for pulpectomyprocedure. The samples were cultured, and purified using microbiological evaluation.Broth dilution test was performed in our study by preparing test tubes containing10 ml of BHI broth (pH. 7) which then inoculated with strains of the tested bacteriaand incubated at 37 C° for 24 h. After over night incubaction, ten fold dilution weremade in test tubes containing 9 ml of normal saline by adding 1 ml of the inoculum tothe first tube . Then from dilution 10-1 , 0.1 ml of cell suspension was added to 9.9 mlof formocresol and endosepton, then 0.1 ml was taken and spread on duplicates ofBHI agar plates at different intervals and incubated aerobically for 24 h. at 37 C°.Colonies on the plates were counted after incubation and CFU/mL (colony formingunit) was calculated. Our results indicating that there were no significant differencesbetween the intracanal medicaments, but there were high significant differencesbetween the intervals time of the study. We concluded that both materials had greatantibacterial effect against the pathogens commonly isolated from necrotic pulpaltissue of primary teeth.

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Distribution of Lactoferrin Is Related with Dynamics of Neutrophils in Bacterial Infected Mice Intestine

Molecules ◽

10.3390/molecules25071496 ◽

2020 ◽

Vol 25 (7) ◽

pp. 1496 ◽

Cited By ~ 1

Author(s):

Li Liang ◽

Zhen-Jie Wang ◽

Guang Ye ◽

Xue-You Tang ◽

Yuan-Yuan Zhang ◽

...

Keyword(s):

Escherichia Coli ◽

Antimicrobial Activity ◽

Mucosal Immunity ◽

Mrna Levels ◽

Iron Binding ◽

E Coli ◽

New Knowledge ◽

Activated Neutrophils ◽

Binding Glycoprotein

Lactoferrin (Lf) is a conserved iron-binding glycoprotein with antimicrobial activity, which is present in secretions that recover mucosal sites regarded as portals of invaded pathogens. Although numerous studies have focused on exogenous Lf, little is known about its expression of endogenous Lf upon bacterial infection. In this study, we investigated the distribution of Lf in mice intestine during Escherichia coli (E. coli) K88 infection. PCR and immunohistology staining showed that mRNA levels of Lf significantly increased in duodenum, ileum and colon, but extremely decreased in jejunum at 8 h and 24 h after infection. Meanwhile, endogenous Lf was mostly located in the lamina propria of intestine villi, while Lf receptor (LfR) was in the crypts. It suggested that endogenous Lf-LfR interaction might not be implicated in the antibacterial process. In addition, it was interesting to find that the infiltration of neutrophils into intestine tissues was changed similarly to Lf expression. It indicated that the variations of Lf expression were rather due to an equilibrium between the recruitment of neutrophils and degranulation of activated neutrophils. Thus, this new knowledge will pave the way to a more effective understanding of the role of Lf in intestinal mucosal immunity.

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From antimicrobial activity to mechanism of resistance: the multifaceted role of simple quaternary ammonium compounds in bacterial eradication

Tetrahedron ◽

10.1016/j.tet.2016.01.014 ◽

2016 ◽

Vol 72 (25) ◽

pp. 3559-3566 ◽

Cited By ~ 48

Author(s):

Kevin P.C. Minbiole ◽

Megan C. Jennings ◽

Laura E. Ator ◽

Jacob W. Black ◽

Melissa C. Grenier ◽

...

Keyword(s):

Antimicrobial Activity ◽

Quaternary Ammonium ◽

Quaternary Ammonium Compounds ◽

Bacterial Eradication ◽

Mechanism Of Resistance ◽

Ammonium Compounds

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Subinhibitory Antimicrobial Concentrations: A Review of In Vitro and In Vivo Data

Canadian Journal of Infectious Diseases ◽

10.1155/1992/793607 ◽

1992 ◽

Vol 3 (4) ◽

pp. 193-201 ◽

Cited By ~ 14

Author(s):

George G Zhanel ◽

Daryl J Hoban ◽

Godfrey KM Harding

Keyword(s):

Antimicrobial Activity ◽

Animal Studies ◽

Molecular Level ◽

Bacterial Virulence ◽

Antibacterial Effects ◽

Wide Range ◽

Immune Defences

Antimicrobial activity is not an ‘all or none’ effect. An increase in the rate and extent of antimicrobial action is usually observed over a wide range of antimicrobial concentrations. Subinhibitory antimicrobial concentrations are well known to produce significant antibacterial effects, and various antimicrobials at subinhibitory concentrations have been reported to inhibit the rate of bacterial growth. Bacterial virulence may be increased or decreased by subinhibitory antimicrobial concentrations by changes in the ability of bacteria to adhere to epithelial cells or by alterations in bacterial susceptibility to host immune defences. Animal studies performed in rats, hamsters and rabbits demonstrate decreased bacterial adherence, reduced infectivity and increased survival of animals treated with subinhibitory antimicrobial concentrations compared to untreated controls. The major future role of investigation of subinhibitory antimicrobial concentrations will be to define more fully, at a molecular level, how antimicrobials exert their antibacterial effects.

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Diverse Mechanisms of Antimicrobial Activities of Lactoferrins, Lactoferricins, and Other Lactoferrin-Derived Peptides

International Journal of Molecular Sciences ◽

10.3390/ijms222011264 ◽

2021 ◽

Vol 22 (20) ◽

pp. 11264

Author(s):

Špela Gruden ◽

Nataša Poklar Ulrih

Keyword(s):

Antimicrobial Activity ◽

Amino Acid ◽

Amino Acid Composition ◽

Molecular Level ◽

Antioxidant Activities ◽

Antimicrobial Activities ◽

Iron Binding ◽

Primary Focus ◽

Binding Glycoprotein

Lactoferrins are an iron-binding glycoprotein that have important protective roles in the mammalian body through their numerous functions, which include antimicrobial, antitumor, anti-inflammatory, immunomodulatory, and antioxidant activities. Among these, their antimicrobial activity has been the most studied, although the mechanism behind antimicrobial activities remains to be elucidated. Thirty years ago, the first lactoferrin-derived peptide was isolated and showed higher antimicrobial activity than the native lactoferrin lactoferricin. Since then, numerous studies have investigated the antimicrobial potencies of lactoferrins, lactoferricins, and other lactoferrin-derived peptides to better understand their antimicrobial activities at the molecular level. This review defines the current antibacterial, antiviral, antifungal, and antiparasitic activities of lactoferrins, lactoferricins, and lactoferrin-derived peptides. The primary focus is on their different mechanisms of activity against bacteria, viruses, fungi, and parasites. The role of their structure, amino-acid composition, conformation, charge, hydrophobicity, and other factors that affect their mechanisms of antimicrobial activity are also reviewed.

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Role of tryptophan degradation in respiratory burst-independent antimicrobial activity of gamma interferon-stimulated human macrophages.

Infection and Immunity ◽

10.1128/iai.57.3.845-849.1989 ◽

1989 ◽

Vol 57 (3) ◽

pp. 845-849 ◽

Cited By ~ 118

Author(s):

H W Murray ◽

A Szuro-Sudol ◽

D Wellner ◽

M J Oca ◽

A M Granger ◽

...

Keyword(s):

Antimicrobial Activity ◽

Respiratory Burst ◽

Gamma Interferon ◽

Human Macrophages ◽

Tryptophan Degradation

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Key role of hydrogen peroxide in antimicrobial activity of spring,Honeydew maquisand chestnut grove Corsican honeys onPseudomonas aeruginosaDNA

Letters in Applied Microbiology ◽

10.1111/lam.12868 ◽

2018 ◽

Vol 66 (5) ◽

pp. 427-433 ◽

Cited By ~ 10

Author(s):

J.-P. Poli ◽

E. Guinoiseau ◽

A. Luciani ◽

Y. Yang ◽

M.-J. Battesti ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Antimicrobial Activity

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Role of ZnO Nanoparticles for improvement of Antibacterial Activity in Food Packaging

Asian Journal of Pharmaceutical Research ◽

10.52711/2231-5691.2021.00024 ◽

2021 ◽

pp. 128-131

Author(s):

Saira Sehar ◽

Amiza Amiza ◽

I. H Khan

Keyword(s):

Antimicrobial Activity ◽

Particle Size ◽

Surface Area ◽

Zno Nanoparticles ◽

Food Packaging ◽

Antimicrobial Agents ◽

Uv Light ◽

Zno Nps ◽

Long Time

Nanotechnology advancement leads to development of antimicrobial agents like ZnO nanoparticles. These nanoparticle have their main applications in food packaging. when these nanoparticles incorporate into the food surface, it will kill all bacterias residing on the surface and food become free of bacteria. In this way, food can be stored for a long time because its shelf life is improved. Antimicrobial activity of ZnO nanoparticles can be improved by increasing surface area, reducing particle size and large concentration of ZnO –NPS. Antimicrobial activity increases by increasing intensity of UV light. As UV light fall on ZnO nanoparticles, it increases ZnO surface area and hence anrtimicrobial activity will be increased. Exact mechanism of Antimicrobial activity is still unknown but some processes have been presented.

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Minocycline in Treating Glioblastoma Multiforme: Far beyond a Conventional Antibiotic

Journal of Oncology ◽

10.1155/2020/8659802 ◽

2020 ◽

Vol 2020 ◽

pp. 1-11

Author(s):

Amir R. Afshari ◽

Hamid Mollazadeh ◽

Amirhossein Sahebkar

Keyword(s):

Antimicrobial Activity ◽

Glioblastoma Multiforme ◽

Cancer Therapy ◽

Cell Invasion ◽

Treatment Approach ◽

Tumor Cell Invasion ◽

Surgical Interventions ◽

Anticancer Effects ◽

New Treatment

One of the most lethal forms of CNS pathologies is glioblastoma multiforme (GBM) that represents high invasiveness, uncontrolled proliferation, and angiogenic features. Its invasiveness is responsible for the high recurrence even after maximal surgical interventions. Minocycline is a semisynthetic analog of tetracyclines with potential anti-inflammatory and anticancer effects, distinct from its antimicrobial activity. In this review, we highlight the importance and the cytotoxic mechanisms of minocycline on GBM pathophysiology. Considering the role of certain enzymes in autophagy, apoptosis, tumor cell invasion, and metastatic ability, the possible use of tetracyclines for cancer therapy should be investigated, especially GBM. The present study is, therefore, going to cover the main topics in minocycline pharmacology to date, encouraging its consideration as a new treatment approach for cancer and GBM.

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