In vitro antibacterial activity and durability of a nano-curcumin-containing pulp capping agent combined with antimicrobial photodynamic therapy

The determination of the antibacterial activity (zone of inhibition) and minimum inhibitory concentration of medicinal plants a crucial step in drug development. In this study, the antibacterial activity and minimum inhibitory concentration of the ethanol extract of Myrsine africana were determined for Escherichia coli, Bacillus cereus, Staphylococcus epidermidis and Streptococcus pneumoniae. The zones of inhibition (mm±S.E) of 500mg/ml of M. africana ethanol extract were 22.00± 0.00 for E. coli,20.33 ±0.33 for B. cereus,25.00± 0.00 for S. epidermidis and 18. 17±0.17 for S. pneumoniae. The minimum inhibitory concentration(MIC) is the minimum dose required to inhibit growth a microorganism. Upon further double dilution of the 500mg/ml of M. africana extract, MIC was obtained for each organism. The MIC for E. coli, B. cereus, S. epidermidis and S. pneumoniae were 7.81mg/ml, 7.81mg/ml, 15.63mg/ml and 15.63mg/ml respectively. Crude extracts are considered active when they inhibit microorganisms with zones of inhibition of 8mm and above. Therefore, this study has shown that the ethanol extract of M. africana can control the growth of the four organisms tested.

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Evaluation of the in vitro antibacterial activity of some essential oils and their blends against Staphylococcus spp. isolated from episodes of sheep mastitis

RENDICONTI LINCEI ◽

10.1007/s12210-021-00991-5 ◽

2021 ◽

Author(s):

Filippo Fratini ◽

Margherita Giusti ◽

Simone Mancini ◽

Francesca Pisseri ◽

Basma Najar ◽

...

Keyword(s):

Antibacterial Activity ◽

Essential Oils ◽

Diffusion Method ◽

Minimal Bactericidal Concentration ◽

Coagulase Negative Staphylococci ◽

Disk Diffusion Method ◽

In Vitro Antibacterial Activity ◽

High Concentrations ◽

Thymus Serpyllum

AbstractStaphylococcus aureus and coagulase-negative staphylococci are among the major causes of mastitis in sheep. The main goal of this research was to determine the in vitro antibacterial activity of several essential oils (EOs, n 30), then five of them were chosen and tested alone and in blends against staphylococci isolates. Five bacteria were isolated from episodes of ovine mastitis (two S. aureus and three S. xylosus). Biochemical and molecular methods were employed to identify the isolates and disk diffusion method was performed to determine their antimicrobial-resistance profile. The relative percentage of the main constituents in the tested essential oils and their blends was detected by GC-EIMS analysis. Antibacterial and bactericidal effectiveness of essential oils and blends were evaluated through minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). All of them showed sensitivity to the used antimicrobials. The EOs with the highest antibacterial activity were those belonging to the Lamiaceae family characterized by high concentrations of thymol, carvacrol and its precursor p-cymene, together with cinnamon EO, rich in cinnamaldehyde. In terms of both MIC and MBC values, the blend composed by Thymus capitatus EO 40%, Cinnamomum zeylanicum EO 20%, Thymus serpyllum EO 20% and Satureja montana EO 20% was found to be the most effective against all the isolates. Some essential oils appear to represent, at least in vitro, a valid tool against ovine mastitis pathogens. Some blends showed a remarkable effectiveness than the single oils, highlighting a synergistic effect in relation to the phytocomplex.

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Synthesis Characterization and In Vitro Antibacterial Activity of the N-Substituted Bis-Pyrazoline Derivative as Polycyclic Aromatic Compounds

Polycyclic Aromatic Compounds ◽

10.1080/10406638.2020.1866040 ◽

2020 ◽

pp. 1-10

Author(s):

Faisal M. Aqlan

Keyword(s):

Antibacterial Activity ◽

Aromatic Compounds ◽

Polycyclic Aromatic Compounds ◽

Polycyclic Aromatic ◽

In Vitro Antibacterial Activity ◽

Pyrazoline Derivative

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Efficiency of Antimicrobial Photodynamic Therapy with Photodithazine® on MSSA and MRSA Strains

Antibiotics ◽

10.3390/antibiotics10070869 ◽

2021 ◽

Vol 10 (7) ◽

pp. 869

Author(s):

Beatriz Müller Nunes Souza ◽

Juliana Guerra Pinto ◽

André Henrique Correia Pereira ◽

Alejandro Guillermo Miñán ◽

Juliana Ferreira-Strixino

Keyword(s):

Staphylococcus Aureus ◽

Photodynamic Therapy ◽

Antimicrobial Photodynamic Therapy ◽

Bacterial Inactivation ◽

Bacterial Reduction ◽

Complete Inactivation ◽

Opportunistic Bacteria ◽

Significant Difference ◽

Mrsa Strains

Staphylococccus aureus is a ubiquitous and opportunistic bacteria associated with high mortality rates. Antimicrobial photodynamic therapy (aPDT) is based on the application of a light source and a photosensitizer that can interact with molecular oxygen, forming Reactive Oxygen Species (ROS) that result in bacterial inactivation. This study aimed to analyze, in vitro, the action of aPDT with Photodithazine® (PDZ) in methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) strains. The strains were incubated with PDZ at 25, 50, 75, and 100 mg/L for 15 min and irradiated with fluences of 25, 50, and 100 J/cm2. The internalization of PDZ was evaluated by confocal microscopy, the bacterial growth by counting the number of colony-forming units, as well as the bacterial metabolic activity post-aPDT and the production of ROS. In both strains, the photosensitizer was internalized; the production of ROS increased when the aPDT was applied; there was a bacterial reduction compared to the control at all the evaluated fluences and concentrations; and, in most parameters, it was obtained complete inactivation with significant difference (p < 0.05). The implementation of aPDT with PDZ in clinical strains of S. aureus has resulted in its complete inactivation, including the MRSA strains.

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Photodynamic Therapy Combined with Antibiotics or Antifungals against Microorganisms That Cause Skin and Soft Tissue Infections: A Planktonic and Biofilm Approach to Overcome Resistances

Pharmaceuticals ◽

10.3390/ph14070603 ◽

2021 ◽

Vol 14 (7) ◽

pp. 603

Author(s):

Vanesa Pérez-Laguna ◽

Isabel García-Luque ◽

Sofía Ballesta ◽

Antonio Rezusta ◽

Yolanda Gilaberte

Keyword(s):

Photodynamic Therapy ◽

Soft Tissues ◽

Combined Treatment ◽

Resistance Pattern ◽

Antimicrobial Photodynamic Therapy ◽

Antimicrobial Drugs ◽

Bacteria And Fungi ◽

High Level ◽

Selection Of

The present review covers combination approaches of antimicrobial photodynamic therapy (aPDT) plus antibiotics or antifungals to attack bacteria and fungi in vitro (both planktonic and biofilm forms) focused on those microorganisms that cause infections in skin and soft tissues. The combination can prevent failure in the fight against these microorganisms: antimicrobial drugs can increase the susceptibility of microorganisms to aPDT and prevent the possibility of regrowth of those that were not inactivated during the irradiation; meanwhile, aPDT is effective regardless of the resistance pattern of the strain and their use does not contribute to the selection of antimicrobial resistance. Additive or synergistic antimicrobial effects in vitro are evaluated and the best combinations are presented. The use of combined treatment of aPDT with antimicrobials could help overcome the difficulty of fighting high level of resistance microorganisms and, as it is a multi-target approach, it could make the selection of resistant microorganisms more difficult.

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In-vitro antibacterial activity of cefoperazone, a piperazine cephalosporin

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/8.2.107 ◽

1981 ◽

Vol 8 (2) ◽

pp. 107-113 ◽

Cited By ~ 3

Author(s):

Anna King ◽

Christine Warren ◽

Kevin Shannon ◽

Ian Phillips

Keyword(s):

Antibacterial Activity ◽

In Vitro Antibacterial Activity

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