Special Issue "Fighting Multidrug Resistance with Natural Antimicrobials"

A special issue of Microorganisms (ISSN 2076-2607). This special issue belongs to the section "Antimicrobial Agents and Resistance".

Deadline for manuscript submissions: closed (30 June 2019).

Special Issue Editor

Dr. Spengler Gabriella
E-Mail Website
Guest Editor
Department of Medical Microbiology and Immunobiology, University of Szeged, H-6720 Szeged, Dóm Square 10, Hungary
Interests: reversal of multidrug resistance in bacteria and cancer cells; efflux pump inhibitors; experimental chemotherapy
Special Issues and Collections in MDPI journals

Special Issue Information

Dear Colleagues,

Based on historical evidence, we know that ancient civilizations already used a variety of natural products for the treatment of infectious diseases. Medicinal plants and marine and terrestrial organisms are great sources of natural antimicrobials, furthermore research on natural compounds can open a new horizon in drug discovery in order to find effective antimicrobial agents.

The rapid spread and evolution of bacterial antimicrobial resistance is a major concern regarding the efficacy of antimicrobial therapy, leading to the need to find new antibacterial and resistant modifying agents. Furthermore, the application of natural compounds can decrease or block certain bacterial virulence factors e.g., the inhibition of over-expressed efflux pumps and biofilm production can contribute to successful treatment. A new perspective could be the combination of conventional antibiotics with natural compounds as adjuvants that can overcome resistance and enhance the activity of the antibiotics.

This Special Issue of Microorganisms invites both reviews and original articles that consider natural antimicrobials as potential drug candidates against multidrug resistant microorganisms. Planned topics include: the discovery of natural antibacterial compounds, application of natural compounds in the antimicrobial therapy, natural efflux pump inhibitors, natural anti-biofilm agents, and the combination of conventional antibiotics and natural compounds. You are also welcome to propose a unique topic.

Dr. Gabriella Spengler
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Microorganisms is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2000 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Published Papers (2 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Communication
Bioactive Compounds of Nigella Sativa Essential Oil as Antibacterial Agents against Chlamydia Trachomatis D
Microorganisms 2019, 7(9), 370; https://0-doi-org.brum.beds.ac.uk/10.3390/microorganisms7090370 - 19 Sep 2019
Cited by 1 | Viewed by 1470
Abstract
Urogenital tract infection caused by obligate intracellular bacterium Chlamydia trachomatis D (CtrD) is a leading cause of sexually transmitted diseases. Essential oil (EO) of Nigella sativa has a broad antimicrobial spectrum. The aim of this study was to evaluate the antimicrobial [...] Read more.
Urogenital tract infection caused by obligate intracellular bacterium Chlamydia trachomatis D (CtrD) is a leading cause of sexually transmitted diseases. Essential oil (EO) of Nigella sativa has a broad antimicrobial spectrum. The aim of this study was to evaluate the antimicrobial activity of the bioactive compounds (p-cymene, thymoquinone, carvacrol, and thymol) of N. sativa EO against CtrD. The cytotoxic effects of the compounds were determined by MTT assay. In order to quantify the anti-chlamydial activity of the compounds, HeLa cells were infected with CtrD or CtrD treated previously with the compounds. The titer of the infectious CtrD was determined by indirect immunofluorescence assay. The minimum inhibitory concentrations of the compounds were evaluated by direct quantitative PCR. None of the compounds showed a cytotoxic effect on HeLa cells in the concentrations tested. According to the immunofluorescence assay, all of the compounds significantly inhibited the growth of CtrD. The quantitative PCR revealed that the minimum concentration that exerted anti-chlamydial activity was 3.12 µM in the case of thymoquinone and p-cymene, while that of carvacrol and thymol was 6.25 µM. Therefore, it can be concluded that bioactive compounds of N. sativa EO could be used as effective antimicrobial agents against CtrD. Full article
(This article belongs to the Special Issue Fighting Multidrug Resistance with Natural Antimicrobials)
Show Figures

Figure 1

Article
Winning the War against Multi-Drug Resistant Diarrhoeagenic Bacteria
Microorganisms 2019, 7(7), 197; https://0-doi-org.brum.beds.ac.uk/10.3390/microorganisms7070197 - 10 Jul 2019
Cited by 2 | Viewed by 1073
Abstract
Drug-resistant-diarrhoeagenic bacteria are currently emerging healthcare challenge. This study investigated the effects of Vernonia amygdalina, Garcinia kola, tetracycline and metronidazole combinations on such bacteria. Agar well diffusion method was employed to determine the inhibitory effects of the herbal extracts on diarrhoeagenic [...] Read more.
Drug-resistant-diarrhoeagenic bacteria are currently emerging healthcare challenge. This study investigated the effects of Vernonia amygdalina, Garcinia kola, tetracycline and metronidazole combinations on such bacteria. Agar well diffusion method was employed to determine the inhibitory effects of the herbal extracts on diarrhoeagenic bacteria while Time-Kill Assay was used to determine bactericidal effects of the extracts against test isolates. Interactions between plant extracts and antibiotics were investigated using Checkerboard assay. Minimum inhibitory concentrations of the extracts against the bacterial isolates ranged between 3.125–50 mg/mL, while those of tetracycline and metronidazole ranged from 30–50 μg/mL. Synergism was observed against B. cereus and S. aureus for metronidazole + aqueous G. kola at all ratios. Generally, the combinations aqueous G. kola + ethanolic G. kola and aqueous G. kola + ethanolic V. amygdalina showed more pronounced synergism against the Staphylococcus aureus than B. cereus isolates with the fractional inhibition concentration (FIC) indices ranging from 0.32–0.95. Synergism of tetracycline + crude extracts and metronidazole combinations were more pronounced on the test isolates and especially on the Gram-negative organisms with FIC indices ranging from 0.41–0.91. Conclusion: The herbal extracts combinations and extracts–antibiotics combinations are synergistic on diarrhoeagenic bacteria at defined combination ratios. Full article
(This article belongs to the Special Issue Fighting Multidrug Resistance with Natural Antimicrobials)
Show Figures

Figure 1

Back to TopTop