Special Issue "Alternatives to Antibiotics: Current Strategies and Future Prospects"

Quicklinks

A special issue of Pathogens (ISSN 2076-0817).

Deadline for manuscript submissions: closed (31 October 2014)

Special Issue Editor

Guest Editor
Dr. Guolong Zhang

Department of Animal Science, Oklahoma State University, Stillwater, OK 74078, USA
Website | E-Mail
Fax: +1 405-744-7390
Interests: innate immunity; host defense peptides; antibiotic alternatives

Special Issue Information

Dear Colleagues,

Subtherapeutic use of antibiotics in animal agriculture poses a serious threat to public health by increasing the risk of disseminating antibiotic-resistant pathogens. The European Union has banned the use of antibiotics as growth promoters. The U.S. Food and Drug Administration is implementing a new policy to phase out the application of medically important antibiotics to healthy animals by December 2016. Alternatives to antibiotics are, therefore, urgently needed to ensure animal health and productivity and food safety and security. Although a long list of compounds are currently available on the antibiotic alternatives market, very few can match the efficacy of antibiotics in growth promotion and disease resistance. This Special Issue will provide an update on our search for more effective antibiotic alternatives. More importantly, some of the promising strategies that are being developed will be highlighted. This special issue will also serve as a platform for leading researchers to discuss the future directions of our pursuit for alternatives to antibiotics.

Dr. Guolong Zhang
Guest Editor

Submission

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. Papers will be published continuously (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as 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 refereed through a peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Pathogens is an international peer-reviewed Open Access quarterly 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 600 CHF (Swiss Francs). English correction and/or formatting fees of 250 CHF (Swiss Francs) will be charged in certain cases for those articles accepted for publication that require extensive additional formatting and/or English corrections.


Keywords

  • antimicrobial resistance
  • antibiotic growth promoters
  • antibiotic alternatives
  • host defense peptides
  • antimicrobial peptides
  • immunomodulators
  • probiotics
  • bacteriocins
  • bacteriophages
  • essential oils
  • phytochemicals

Published Papers (5 papers)

View options order results:
result details:
Displaying articles 1-5
Export citation of selected articles as:

Research

Jump to: Review

Open AccessArticle Effect of Bile Salt Hydrolase Inhibitors on a Bile Salt Hydrolase from Lactobacillus acidophilus
Pathogens 2014, 3(4), 947-956; doi:10.3390/pathogens3040947
Received: 3 November 2014 / Revised: 11 December 2014 / Accepted: 12 December 2014 / Published: 17 December 2014
Cited by 1 | PDF Full-text (620 KB) | HTML Full-text | XML Full-text
Abstract
Bile salt hydrolase (BSH), a widely distributed function of the gut microbiota, has a profound impact on host lipid metabolism and energy harvest. Recent studies suggest that BSH inhibitors are promising alternatives to antibiotic growth promoters (AGP) for enhanced animal growth performance and
[...] Read more.
Bile salt hydrolase (BSH), a widely distributed function of the gut microbiota, has a profound impact on host lipid metabolism and energy harvest. Recent studies suggest that BSH inhibitors are promising alternatives to antibiotic growth promoters (AGP) for enhanced animal growth performance and food safety. Using a high-purity BSH from Lactobacillus salivarius strain, we have identified a panel of BSH inhibitors. However, it is still unknown if these inhibitors also effectively inhibit the function of the BSH enzymes from other bacterial species with different sequence and substrate spectrum. In this study, we performed bioinformatics analysis and determined the inhibitory effect of identified BSH inhibitors on a BSH from L. acidophilus. Although the L. acidophilus BSH is phylogenetically distant from the L. salivarius BSH, sequence analysis and structure modeling indicated the two BSH enzymes contain conserved, catalytically important amino residues and domain. His-tagged recombinant BSH from L. acidophilus was further purified and used to determine inhibitory effect of specific compounds. Previously identified BSH inhibitors also exhibited potent inhibitory effects on the L. acidophilus BSH. In conclusion, this study demonstrated that the BSH from L. salivarius is an ideal candidate for screening BSH inhibitors, the promising alternatives to AGP for enhanced feed efficiency, growth performance and profitability of food animals. Full article
(This article belongs to the Special Issue Alternatives to Antibiotics: Current Strategies and Future Prospects)
Open AccessArticle Wild Mushroom Extracts as Inhibitors of Bacterial Biofilm Formation
Pathogens 2014, 3(3), 667-679; doi:10.3390/pathogens3030667
Received: 19 June 2014 / Revised: 11 July 2014 / Accepted: 29 July 2014 / Published: 6 August 2014
Cited by 4 | PDF Full-text (400 KB) | HTML Full-text | XML Full-text
Abstract
Microorganisms can colonize a wide variety of medical devices, putting patients in risk for local and systemic infectious complications, including local-site infections, catheter-related bloodstream infections, and endocarditis. These microorganisms are able to grow adhered to almost every surface, forming architecturally complex communities termed
[...] Read more.
Microorganisms can colonize a wide variety of medical devices, putting patients in risk for local and systemic infectious complications, including local-site infections, catheter-related bloodstream infections, and endocarditis. These microorganisms are able to grow adhered to almost every surface, forming architecturally complex communities termed biofilms. The use of natural products has been extremely successful in the discovery of new medicine, and mushrooms could be a source of natural antimicrobials. The present study reports the capacity of wild mushroom extracts to inhibit in vitro biofilm formation by multi-resistant bacteria. Four Gram-negative bacteria biofilm producers (Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, and Acinetobacter baumannii) isolated from urine were used to verify the activity of Russula delica, Fistulina hepatica, Mycena rosea, Leucopaxilus giganteus, and Lepista nuda extracts. The results obtained showed that all tested mushroom extracts presented some extent of inhibition of biofilm production. Pseudomonas aeruginosa was the microorganism with the highest capacity of biofilm production, being also the most susceptible to the extracts inhibition capacity (equal or higher than 50%). Among the five tested extracts against E. coli, Leucopaxillus giganteus (47.8%) and Mycenas rosea (44.8%) presented the highest inhibition of biofilm formation. The extracts exhibiting the highest inhibitory effect upon P. mirabilis biofilm formation were Sarcodon imbricatus (45.4%) and Russula delica (53.1%). Acinetobacter baumannii was the microorganism with the lowest susceptibility to mushroom extracts inhibitory effect on biofilm production (highest inhibition—almost 29%, by Russula delica extract). This is a pioneer study since, as far as we know, there are no reports on the inhibition of biofilm production by the studied mushroom extracts and in particular against multi-resistant clinical isolates; nevertheless, other studies are required to elucidate the mechanism of action. Full article
(This article belongs to the Special Issue Alternatives to Antibiotics: Current Strategies and Future Prospects)

Review

Jump to: Research

Open AccessReview Phytogenic Compounds as Alternatives to In-Feed Antibiotics: Potentials and Challenges in Application
Pathogens 2015, 4(1), 137-156; doi:10.3390/pathogens4010137
Received: 3 February 2015 / Revised: 18 March 2015 / Accepted: 19 March 2015 / Published: 23 March 2015
Cited by 5 | PDF Full-text (292 KB) | HTML Full-text | XML Full-text
Abstract
This article summarizes current experimental knowledge on the efficacy, possible mechanisms and feasibility in the application of phytogenic products as feed additives for food-producing animals. Phytogenic compounds comprise a wide range of plant-derived natural bioactive compounds and essential oils are a major group.
[...] Read more.
This article summarizes current experimental knowledge on the efficacy, possible mechanisms and feasibility in the application of phytogenic products as feed additives for food-producing animals. Phytogenic compounds comprise a wide range of plant-derived natural bioactive compounds and essential oils are a major group. Numerous studies have demonstrated that phytogenic compounds have a variety of functions, including antimicrobial/antiviral, antioxidative and anti-inflammation effects and improvement in the palatability of feed and gut development/health. However, the mechanisms underlying their functions are still largely unclear. In the past, there has been a lack of consistency in the results from both laboratory and field studies, largely due to the varied composition of products, dosages, purities and growing conditions of animals used. The minimal inhibitory concentration (MIC) of phytogenic compounds required for controlling enteric pathogens may not guarantee the best feed intake, balanced immunity of animals and cost-effectiveness in animal production. The lipophilic nature of photogenic compounds also presents a challenge in effective delivery to the animal gut and this can partially be resolved by microencapsulation and combination with other compounds (synergistic effect). Interestingly, the effects of photogenic compounds on anti-inflammation, gut chemosensing and possible disruption of bacterial quorum sensing could explain a certain number of studies with different animal species for the better production performance of animals that have received phytogenic feed additives. It is obvious that phytogenic compounds have good potential as an alternative to antibiotics in feed for food animal production and the combination of different phytogenic compounds appears to be an approach to improve the efficacy and safety of phytogenic compounds in the application. It is our expectation that the recent development of high-throughput and “omics” technologies can significantly advance the studies on the mechanisms underlying phytogenic compounds’ functions and, therefore, guide the effective use of the compounds. Full article
(This article belongs to the Special Issue Alternatives to Antibiotics: Current Strategies and Future Prospects)
Open AccessReview The Use of Lactic Acid Bacteria as a Probiotic in Swine Diets
Pathogens 2015, 4(1), 34-45; doi:10.3390/pathogens4010034
Received: 6 November 2014 / Revised: 22 December 2014 / Accepted: 22 January 2015 / Published: 27 January 2015
Cited by 6 | PDF Full-text (216 KB) | HTML Full-text | XML Full-text
Abstract
As the resistance of pathogens to antibiotics and the possibility of antibiotic residues in animal products attract increasing attention, the interest in the use of alternatives to in-feed antibiotics has been growing. Recent research with Lactic acid bacteria (LAB) in pigs suggests that
[...] Read more.
As the resistance of pathogens to antibiotics and the possibility of antibiotic residues in animal products attract increasing attention, the interest in the use of alternatives to in-feed antibiotics has been growing. Recent research with Lactic acid bacteria (LAB) in pigs suggests that LAB provide a potential alternative to antibiotic strategies. LAB include Lactobacillus species, Bifidobacterium spp, Bacillus spp, and some other microbes. LAB can adjust the intestinal environment, inhibit or kill pathogens in the gastrointestinal tract and improve the microbial balance in the intestine, as well as regulate intestinal mucosal immunity and maintain intestinal barrier function, thereby benefiting the health of pigs. The related mechanisms for these effects of LAB may include producing microbicidal substances with effects against gastrointestinal pathogens and other harmful microbes, competing with pathogens for binding sites on the intestinal epithelial cell surface and mucin as well as stimulating the immune system. In this review, the characteristics of LAB and their probiotic effects in newborn piglets, weaned piglets, growing pigs and sows are documented. Full article
(This article belongs to the Special Issue Alternatives to Antibiotics: Current Strategies and Future Prospects)
Open AccessReview Alternatives to Antibiotics in Animal Agriculture: An Ecoimmunological View
Pathogens 2015, 4(1), 1-19; doi:10.3390/pathogens4010001
Received: 25 October 2014 / Accepted: 24 December 2014 / Published: 29 December 2014
PDF Full-text (247 KB) | HTML Full-text | XML Full-text
Abstract
Ecological immunology (or ecoimmunology) is a new discipline in animal health and immunology that extends immunologists’ views into a natural context where animals and humans have co-evolved. Antibiotic resistance and tolerance (ART) in bacteria are manifested in antibiosis-surviving subsets of resisters and persisters.
[...] Read more.
Ecological immunology (or ecoimmunology) is a new discipline in animal health and immunology that extends immunologists’ views into a natural context where animals and humans have co-evolved. Antibiotic resistance and tolerance (ART) in bacteria are manifested in antibiosis-surviving subsets of resisters and persisters. ART has emerged though natural evolutionary consequences enriched by human nosocomial and agricultural practices, in particular, wide use of antibiotics that overwhelms other ecological and immunological interactions. Most previous reviews of antibiotic resistance focus on resisters but overlook persisters, although both are fundamental to bacteria survival through antibiosis. Here, we discuss resisters and persisters together to contrast the distinct ecological responses of persisters during antibiotic stress and propose different regimens to eradicate persisters. Our intention is not only to provide an ecoimmunological interpretation, but also to use an ecoimmunological system to categorize available alternatives and promote the discovery of prospective approaches to relieve ART problems within the general scope of improving animal health. Thus, we will categorize available alternatives to antibiotics and envision applications of ecoimmunological tenets to promote related studies in animal production. Full article
(This article belongs to the Special Issue Alternatives to Antibiotics: Current Strategies and Future Prospects)

Journal Contact

MDPI AG
Pathogens Editorial Office
St. Alban-Anlage 66, 4052 Basel, Switzerland
pathogens@mdpi.com
Tel. +41 61 683 77 34
Fax: +41 61 302 89 18
Editorial Board
Contact Details Submit to Pathogens
Back to Top