Green Antimicrobials

A special issue of Antibiotics (ISSN 2079-6382). This special issue belongs to the section "Novel Antimicrobial Agents".

Deadline for manuscript submissions: closed (31 March 2023) | Viewed by 32547

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Guest Editor
Centre for Textile Science and Technology, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal
Interests: antimicrobial agents; regenerative cues; drug delivery; biomaterials; wound healing; medical textiles; polymer processing; nano- and microfiber scaffolding systems
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Dear Colleagues,

In the last couple of years, the awareness of climate change and high pollution levels have raised our sense of ecological responsibility. Pharmaceutical industries play a major role in these issues; as such, alternatives must be found. New environmentally friendly approaches to deal with the growing concern associated with antimicrobial-resistant bacteria are also in great demand. The excessive consumption and misuse of these agents have accelerated the rise of such pathogens responsible for compromising global health, not only of humans but of all living systems. Considering our natural resources are in great danger, finding green and less environmentally impactful alternatives for fighting these resistant microbials is imperative. From green chemistries, natural extracts, and waste products, the sources for these alternate antimicrobial cues can be immense and the potentialities of great impact for future generations.

This Special Issue seeks manuscript submissions that further our understanding of the antimicrobial action of specialized molecules (organic and inorganic) derived from green, ecofriendly processes as alternatives to conventional antibiotics or other antimicrobial agents. Submissions on the response of microorganisms to these agents, their contribution to infection control, and prevention of serious conditions/illnesses from occurring or evolving are especially encouraged. Publications on the chemical modification, transformation, or engineering of such green systems, with improved antimicrobial effects, are highly welcome. It is expected that these formulations will provide advantageous performance over pollutant options to allow us to take one step towards the resolution of the antibiotic crisis while still protecting our fundamental bio-resources.

Dr. Helena P. Felgueiras
Guest Editor

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Keywords

  • antimicrobial actions
  • concomitant, synergistic, and additive effects
  • surface functionalization
  • bioactive cues
  • biomolecules
  • green synthesis
  • environmentally friendly
  • circular economy
  • waste-materials second life

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Published Papers (13 papers)

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Editorial

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3 pages, 190 KiB  
Editorial
Green Antimicrobials
by Helena P. Felgueiras
Antibiotics 2023, 12(7), 1128; https://doi.org/10.3390/antibiotics12071128 - 29 Jun 2023
Viewed by 1028
Abstract
In the last couple of years, the awareness of climate change and high pollution levels have raised our sense of ecological responsibility [...] Full article
(This article belongs to the Special Issue Green Antimicrobials)

Research

Jump to: Editorial, Review

23 pages, 8639 KiB  
Article
Evaluating Biofilm Inhibitory Potential in Fish Pathogen, Aeromonas hydrophila by Agricultural Waste Extracts and Assessment of Aerolysin Inhibitors Using In Silico Approach
by Manikandan Arumugam, Dinesh Babu Manikandan, Sathish Kumar Marimuthu, Govarthanan Muthusamy, Zulhisyam Abdul Kari, Guillermo Téllez-Isaías and Thirumurugan Ramasamy
Antibiotics 2023, 12(5), 891; https://doi.org/10.3390/antibiotics12050891 - 11 May 2023
Cited by 2 | Viewed by 2293
Abstract
Aeromonas hydrophila, an opportunistic bacteria, causes several devastating diseases in humans and animals, particularly aquatic species. Antibiotics have been constrained by the rise of antibiotic resistance caused by drug overuse. Therefore, new strategies are required to prevent appropriate antibiotic inability from antibiotic-resistant [...] Read more.
Aeromonas hydrophila, an opportunistic bacteria, causes several devastating diseases in humans and animals, particularly aquatic species. Antibiotics have been constrained by the rise of antibiotic resistance caused by drug overuse. Therefore, new strategies are required to prevent appropriate antibiotic inability from antibiotic-resistant strains. Aerolysin is essential for A. hydrophila pathogenesis and has been proposed as a potential target for inventing drugs with anti-virulence properties. It is a unique method of disease prevention in fish to block the quorum-sensing mechanism of A. hydrophila. In SEM analysis, the crude solvent extracts of both groundnut shells and black gram pods exhibited a reduction of aerolysin formation and biofilm matrix formation by blocking the QS in A. hydrophila. Morphological changes were identified in the extracts treated bacterial cells. Furthermore, in previous studies, 34 ligands were identified with potential antibacterial metabolites from agricultural wastes, groundnut shells, and black gram pods using a literature survey. Twelve potent metabolites showed interactions between aerolysin and metabolites during molecular docking analysis, in that H-Pyran-4-one-2,3 dihydro-3,5 dihydroxy-6-methyl (−5.3 kcal/mol) and 2-Hexyldecanoic acid (−5.2 kcal/mol) showed promising results with potential hydrogen bond interactions with aerolysin. These metabolites showed a better binding affinity with aerolysin for 100 ns in molecular simulation dynamics. These findings point to a novel strategy for developing drugs using metabolites from agricultural wastes that may be feasible pharmacological solutions for treating A. hydrophila infections for the betterment of aquaculture. Full article
(This article belongs to the Special Issue Green Antimicrobials)
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21 pages, 2464 KiB  
Article
Synergistic Antimicrobial Activity of Ceftriaxone and Polyalthia longifolia Methanol (MEPL) Leaf Extract against Methicillin-Resistant Staphylococcus aureus and Modulation of mecA Gene Presence
by Valiappan Ranjutha, Yeng Chen, Lamya Ahmed Al-Keridis, Mitesh Patel, Nawaf Alshammari, Mohd Adnan, Sumaira Sahreen, Subash C. B. Gopinath and Sreenivasan Sasidharan
Antibiotics 2023, 12(3), 477; https://doi.org/10.3390/antibiotics12030477 - 27 Feb 2023
Cited by 6 | Viewed by 2177
Abstract
Medicinal plants are an essential source of traditional curatives for numerous skin diseases. Polyalthia longifolia (Sonn.) Thwaites (Annonaceae family) is a medicinal plant used to cure skin illnesses. P. longifolia is usually applied in folkloric therapeutical systems to treat skin diseases. The methicillin-resistant [...] Read more.
Medicinal plants are an essential source of traditional curatives for numerous skin diseases. Polyalthia longifolia (Sonn.) Thwaites (Annonaceae family) is a medicinal plant used to cure skin illnesses. P. longifolia is usually applied in folkloric therapeutical systems to treat skin diseases. The methicillin-resistant Staphylococcus aureus (MRSA) bacteria is among the essential bacteria contributing to skin diseases. Hence, to verify the traditional medicinal claim of P. longifolia usage in skin disease treatment, the current research was performed to study the synergistic antibacterial activity of standardized Polyalthia longifolia methanol leaf extract (MEPL) against MRSA bacteria. The synergistic antimicrobial activity result of ceftriaxone, when mixed with MEPL, against MRSA was investigated by the disc diffusion method, broth microdilution method, checkerboard dilution test, and modulation of mecA gene expression by multiplex polymerase chain reaction (multiplex PCR). The MEPL extract exhibited good synergistic antimicrobial activity against MRSA. Using the checkerboard method, we confirmed the synergistic effect of MEPL from P. longifolia and ceftriaxone (2:1) for MRSA with a marked reduction of the MIC value of the ceftriaxone from 8000 µg/mL to 1000 µg/mL. Moreover, the combination of MEPL with ceftriaxone significantly (p < 0.05) inhibited the presence of the resistant mecA gene in the tested strain. The LC–ESI–MS/MS analysis identified compounds that were reported to exhibit antimicrobial activity. Conclusively, the MEPL extract, an important etiological agent for skin diseases, showed worthy synergistic antimicrobial action against MRSA bacteria, thus supporting the traditional use of P. longifolia. Full article
(This article belongs to the Special Issue Green Antimicrobials)
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10 pages, 3328 KiB  
Article
Antimicrobial Polymeric Surfaces Using Embedded Silver Nanoparticles
by Pooja Sharma, Luisa Fialho, Nuno Miguel Figueiredo, Ricardo Serra, Albano Cavaleiro and Sandra Carvalho
Antibiotics 2023, 12(2), 207; https://doi.org/10.3390/antibiotics12020207 - 18 Jan 2023
Cited by 4 | Viewed by 1483
Abstract
Pathogens (disease-causing microorganisms) can survive up to a few days on surfaces and can propagate through surfaces in high percentages, and thus, these surfaces turn into a primary source of pathogen transmission. To prevent and mitigate pathogen transmission, antimicrobial surfaces seem to be [...] Read more.
Pathogens (disease-causing microorganisms) can survive up to a few days on surfaces and can propagate through surfaces in high percentages, and thus, these surfaces turn into a primary source of pathogen transmission. To prevent and mitigate pathogen transmission, antimicrobial surfaces seem to be a promising option that can be prepared by using resilient, mass-produced polymers with partly embedded antimicrobial nanoparticles (NPs) with controlled size. In the present study, a 6 nm thick Ag nanolayer was sputter deposited on polycarbonate (PC) substrate and then thermally annealed, in a first step at 120 °C (temperature below Tg) for two hours, for promoting NP diffusion and growth, and in a second step at 180 °C (temperature above Tg) for 22 h, for promoting thermal embedding of the NPs into the polymer surface. The variation in the height of NPs on the polymer surface with thermal annealing confirms the embedding of NPs. It was shown that the incorporation of silver nanoparticles (Ag NPs) had a great impact on the antibacterial capacity, as the Ag NP-embedded polymer surface presented an inhibition effect on the growth of Gram-positive and Gram-negative bacteria. The tested surface-engineering process of incorporating antimicrobial Ag NPs in a polymer surface is both cost-effective and highly scalable. Full article
(This article belongs to the Special Issue Green Antimicrobials)
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12 pages, 1329 KiB  
Article
Microbial Community Structure among Honey Samples of Different Pollen Origin
by Elisavet Stavropoulou, Nikolaos Remmas, Chrysoula (Chrysa) Voidarou, Georgia Vrioni, Theodoros Konstantinidis, Spyridon Ntougias and Athanasios Tsakris
Antibiotics 2023, 12(1), 101; https://doi.org/10.3390/antibiotics12010101 - 6 Jan 2023
Cited by 4 | Viewed by 2224
Abstract
Honey’s antibacterial activity has been recently linked to the inhibitory effects of honey microbiota against a range of foodborne and human pathogens. In the current study, the microbial community structure of honey samples exerting pronounced antimicrobial activity was examined. The honey samples were [...] Read more.
Honey’s antibacterial activity has been recently linked to the inhibitory effects of honey microbiota against a range of foodborne and human pathogens. In the current study, the microbial community structure of honey samples exerting pronounced antimicrobial activity was examined. The honey samples were obtained from different geographical locations in Greece and had diverse pollen origin (fir, cotton, fir–oak, and Arbutus unedo honeys). Identification of honey microbiota was performed by high-throughput amplicon sequencing analysis, detecting 335 distinct taxa in the analyzed samples. Regarding ecological indices, the fir and cotton honeys possessed greater diversity than the fir–oak and Arbutus unedo ones. Lactobacillus kunkeei (basionym of Apilactobacillus kun-keei) was the predominant taxon in the fir honey examined. Lactobacillus spp. appeared to be favored in honey from fir-originated pollen and nectar since lactobacilli were more pronounced in fir compared to fir–oak honey. Pseudomonas, Streptococcus, Lysobacter and Meiothermus were the predominant taxa in cotton honey, whereas Lonsdalea, the causing agent of acute oak decline, and Zymobacter, an osmotolerant facultative anaerobic fermenter, were the dominant taxa in fir–oak honey. Moreover, methylotrophic bacteria represented 1.3–3% of the total relative abundance, independently of the geographical and pollen origin, indicating that methylotrophy plays an important role in honeybee ecology and functionality. A total of 14 taxa were identified in all examined honey samples, including bacilli/anoxybacilli, paracocci, lysobacters, pseudomonads, and sphingomonads. It is concluded that microbial constituents of the honey samples examined were native gut microbiota of melliferous bees and microbiota of their flowering plants, including both beneficial bacteria, such as potential probiotic strains, and animal and plant pathogens, e.g., Staphylococcus spp. and Lonsdalea spp. Further experimentation will elucidate aspects of potential application of microbial bioindicators in identifying the authenticity of honey and honeybee-derived products. Full article
(This article belongs to the Special Issue Green Antimicrobials)
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0 pages, 965 KiB  
Article
Citizen Contribution for Searching for Alternative Antimicrobial Activity Substances in Soil
by Rosa Fernández-Fernández, Beatriz Robredo, Enrique Navajas and Carmen Torres
Antibiotics 2023, 12(1), 57; https://doi.org/10.3390/antibiotics12010057 - 29 Dec 2022
Cited by 3 | Viewed by 1763
Abstract
Antimicrobial resistance (AMR) is problematic worldwide, and due to the loss of efficiency of many antibiotics, the pressure to discover alternative antimicrobial molecules has increased. Soil harbors a great biodiversity and biomass of microorganisms, and many antibiotics are produced by soil microbiota. Therefore, [...] Read more.
Antimicrobial resistance (AMR) is problematic worldwide, and due to the loss of efficiency of many antibiotics, the pressure to discover alternative antimicrobial molecules has increased. Soil harbors a great biodiversity and biomass of microorganisms, and many antibiotics are produced by soil microbiota. Therefore, soil is a promising reservoir to find new antimicrobial agents. In this respect, novel pedagogical strategies regarding the AMR global crisis have recently been developed in different countries worldwide. Highlighted is the service-learning project “MicroMundo” integrated in a global Citizen Science project called “Tiny Earth”. Hence, the present work aimed at determining the antimicrobial activity of soil bacteria, the biodiversity of the selected isolates as putative antimicrobial producers, and their antibiotic resistance profile. Moreover, through the MicroMundo project, we tried to illustrate the relevant link between science and education and the benefits of implementing service-learning methodologies to raise awareness of the AMR problem and to contribute to the search for new alternatives. A total of 16 teachers, 25 university students and 300 secondary school students participated in the search for antimicrobial activity on a collection of 2600 isolates obtained from a total of 130 soil samples analysed. In total, 132 isolates (5% of total tested) were selected as potential antimicrobial producers when two indicator bacteria were used (Escherichia coli and Staphylococcus epidermidis); the most frequent genus among these isolates was Bacillus, followed by Pseudomonas, Paenibacillus and Serratia. The antimicrobial activity (AA) of the 132 potential antimicrobial producers was studied in a second step against 15 indicator bacteria (of six genera and thirteen species, including relevant pathogens). Of the 132 potentially producing bacteria, 32 were selected for further characterization. In this respect, 18 isolates showed low AA, 12 isolates were considered as medium producers, and 2 highly antimicrobial-producing isolates were found (Brevibacillus laterosporus X7262 and Staphylococcus hominis X7276) showing AA against 80% of the 15 indicators tested. Moreover, 48% of the antimicrobial-producing bacteria were susceptible to all antibiotics tested. Due to citizen science, antimicrobial-producing bacteria of great interest have been isolated, managing to raise awareness about the problem of AMR. Full article
(This article belongs to the Special Issue Green Antimicrobials)
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30 pages, 23373 KiB  
Article
Integrating Network Pharmacology Approaches to Decipher the Multi-Target Pharmacological Mechanism of Microbial Biosurfactants as Novel Green Antimicrobials against Listeriosis
by Mohd Adnan, Arif Jamal Siddiqui, Emira Noumi, Sami Hannachi, Syed Amir Ashraf, Amir Mahgoub Awadelkareem, Mejdi Snoussi, Riadh Badraoui, Fevzi Bardakci, Manojkumar Sachidanandan, Mirav Patel and Mitesh Patel
Antibiotics 2023, 12(1), 5; https://doi.org/10.3390/antibiotics12010005 - 20 Dec 2022
Cited by 9 | Viewed by 2420
Abstract
Listeria monocytogenes (L. monocytogenes) is a serious food-borne pathogen that can cause listeriosis, an illness caused by eating food contaminated with this pathogen. Currently, the treatment or prevention of listeriosis is a global challenge due to the resistance of bacteria against [...] Read more.
Listeria monocytogenes (L. monocytogenes) is a serious food-borne pathogen that can cause listeriosis, an illness caused by eating food contaminated with this pathogen. Currently, the treatment or prevention of listeriosis is a global challenge due to the resistance of bacteria against multiple commonly used antibiotics, thus necessitating the development of novel green antimicrobials. Scientists are increasingly interested in microbial surfactants, commonly known as “biosurfactants”, due to their antimicrobial properties and eco-friendly nature, which make them an ideal candidate to combat a variety of bacterial infections. Therefore, the present study was designed to use a network pharmacology approach to uncover the active biosurfactants and their potential targets, as well as the signaling pathway(s) involved in listeriosis treatment. In the framework of this study, 15 biosurfactants were screened out for subsequent studies. Among 546 putative targets of biosurfactants and 244 targets of disease, 37 targets were identified as potential targets for treatment of L. monocytogenes infection, and these 37 targets were significantly enriched in a Gene Ontology (GO) analysis, which aims to identify those biological processes, cellular locations, and molecular functions that are impacted in the condition studied. The obtained results revealed several important biological processes, such as positive regulation of MAP kinase activity, protein kinase B signaling, ERK1 and ERK2 cascade, ERBB signaling pathway, positive regulation of protein serine/threonine kinase activity, and regulation of caveolin-mediated endocytosis. Several important KEGG pathways, such as the ERBBB signaling pathway, TH17 cell differentiation, HIF-1 signaling pathway, Yersinia infection, Shigellosis, and C-type lectin receptor signaling pathways, were identified. The protein–protein interaction analysis yielded 10 core targets (IL2, MAPK1, EGFR, PTPRC, TNF, ITGB1, IL1B, ERBB2, SRC, and mTOR). Molecular docking was used in the latter part of the study to verify the effectiveness of the active biosurfactants against the potential targets. Lastly, we found that a few highly active biosurfactants, namely lichenysin, iturin, surfactin, rhamnolipid, subtilisin, and polymyxin, had high binding affinities towards IL2, MAPK1, EGFR, PTPRC, TNF, ITGB1, IL1B, ERBB2, SRC, and mTOR, which may act as potential therapeutic targets for listeriosis. Overall, based on the integrated network pharmacology and docking analysis, we found that biosurfactants possess promising anti-listeriosis properties and explored the pharmacological mechanisms behind their effect, laying the groundwork for further research and development. Full article
(This article belongs to the Special Issue Green Antimicrobials)
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17 pages, 5983 KiB  
Article
Biosynthesised Silver Nanoparticles Loading onto Biphasic Calcium Phosphate for Antibacterial and Bone Tissue Engineering Applications
by Varun Prasath Padmanabhan, Pugalmani Sivashanmugam, Ravichandran Kulandaivelu, Suresh Sagadevan, Balu Sridevi, Rajakumar Govindasamy and Muthu Thiruvengadam
Antibiotics 2022, 11(12), 1780; https://doi.org/10.3390/antibiotics11121780 - 8 Dec 2022
Cited by 9 | Viewed by 1878
Abstract
Biphasic calcium phosphate (BCP) serves as one of the substitutes for bone as it consists of an intimate mixture of beta-tricalcium phosphate (β-TCP) and hydroxyapatite (HAP) in different ratios. BCP, because of its inbuilt properties such as osteoconductivity, biocompatibility, and biostability in several [...] Read more.
Biphasic calcium phosphate (BCP) serves as one of the substitutes for bone as it consists of an intimate mixture of beta-tricalcium phosphate (β-TCP) and hydroxyapatite (HAP) in different ratios. BCP, because of its inbuilt properties such as osteoconductivity, biocompatibility, and biostability in several clinical models serves as a bone substituent for orthopedic applications. Therefore, the present study aimed to assess the effectiveness of silver (Ag) nanoparticles (NPs) combined with BCP composites for the orthopedic sector of bone tissue regeneration and growth. In this regard, we first synthesized Ag-BCP microclusters by the double-emulsion method and then characterized the composite for various physicochemical properties, including the crystallinity and crystal structure, bonding and functionality, porosity, morphology, surface charges, topography, and thermal stability. In addition, the antibacterial activity of Ag-BCP was tested against gram-positive and gram-negative microorganisms such as Staphylococcus aureus, Candida albicans, and Escherichia coli. Finally, the cytocompatibility of Ag-BCP was confirmed against the fibroblast cells in vitro. Full article
(This article belongs to the Special Issue Green Antimicrobials)
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14 pages, 1742 KiB  
Article
An Optimization of Oregano, Thyme, and Lemongrass Essential Oil Blend to Simultaneous Inactivation of Relevant Foodborne Pathogens by Simplex–Centroid Mixture Design
by Luiz Torres Neto, Maria Lúcia Guerra Monteiro, Maxsueli Aparecida Moura Machado, Diego Galvan and Carlos Adam Conte Junior
Antibiotics 2022, 11(11), 1572; https://doi.org/10.3390/antibiotics11111572 - 8 Nov 2022
Cited by 11 | Viewed by 3135
Abstract
(1) Background: This study aimed to use the simplex–centroid mixture design methodology coupled with a microdilution assay to predict optimal essential oil (EO) formulations against three potential foodborne pathogens simultaneously through the desirability (D) function. (2) Methods: Oregano (ORE; Origanum vulgare), thyme [...] Read more.
(1) Background: This study aimed to use the simplex–centroid mixture design methodology coupled with a microdilution assay to predict optimal essential oil (EO) formulations against three potential foodborne pathogens simultaneously through the desirability (D) function. (2) Methods: Oregano (ORE; Origanum vulgare), thyme (THY; Thymus vulgaris), and lemongrass (LG; Cymbopogon citratus) and their blends were evaluated concerning minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for Salmonella enterica serotype Enteritidis, Escherichia coli and Staphylococcus aureus. (3) Results: THY combined with ORE or LG were the most promising EO formulations in inhibiting and killing each bacterium separately. Regarding the simultaneous effect, the optimal proportion for maximum inhibition was composed of 75% ORE, 15% THY, and 10% LG, while for maximum inactivation was 50% ORE, 40% THY, and 10% LG. (4) Conclusion: The multiresponse optimization allowed identifying an EO blend to simultaneously control three potential foodborne pathogens. This first report could be a helpful natural and green alternative for the industry to produce safer food products and mitigate public health risks. Full article
(This article belongs to the Special Issue Green Antimicrobials)
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14 pages, 1747 KiB  
Article
Effect of β-Glucan Supplementation on Growth Performance and Intestinal Epithelium Functions in Weaned Pigs Challenged by Enterotoxigenic Escherichia coli
by Yuankang Zhou, Yuheng Luo, Bing Yu, Ping Zheng, Jie Yu, Zhiqing Huang, Xiangbing Mao, Junqiu Luo, Hui Yan and Jun He
Antibiotics 2022, 11(4), 519; https://doi.org/10.3390/antibiotics11040519 - 13 Apr 2022
Cited by 11 | Viewed by 2241
Abstract
Background: To examine the effect of β-glucan (BGL) supplementation on growth performance and intestinal epithelium functions in weaned pigs upon Enterotoxigenic Escherichia coli (ETEC) challenge. Methods: Thirty-two weaned pigs (Duroc × Landrace × Yorkshire) were assigned into four groups. Pigs fed with a [...] Read more.
Background: To examine the effect of β-glucan (BGL) supplementation on growth performance and intestinal epithelium functions in weaned pigs upon Enterotoxigenic Escherichia coli (ETEC) challenge. Methods: Thirty-two weaned pigs (Duroc × Landrace × Yorkshire) were assigned into four groups. Pigs fed with a basal diet or basal diet containing 500 mg/kg BGL were orally infused with ETEC or culture medium. Results: Results showed BGL tended to increase the average daily gain (ADG) in ETEC-challenged pigs (0.05 < p < 0.1). Dietary BGL supplementation had no significant influence on nutrient digestibility (p > 0.05). However, BGL improved the serum concentrations of immunoglobulin (Ig) A and IgG, and was beneficial to relieve the increasement of the concentrations of inflammatory cytokines such as the TNF-α and IL-6 upon ETEC-challenge (p < 0.05). Interestingly, BGL significantly increased the duodenal, jejunal and ileal villus height, and increased the jejunal ratio of villus height to crypt depth (V/C) upon ETEC challenge (p < 0.05). BGL also increased the activities of mucosal, sucrase and maltase in the ETEC-challenged pigs (p < 0.05). Moreover, BGL elevated the abundance of Lactobacillus and the concentration of propanoic acid in colon in the ETEC-challenged pigs (p < 0.05). Importantly, BGL elevated the expression levels of zonula occludins-1 (ZO-1) and mucin-2 (MUC-2) in the small intestinal mucosa upon ETEC challenge (p < 0.05). BGL also upregulated the expressions of functional genes such as the claudin-1, cationic amino acid transporter-1 (CAT-1), LAT-1, L amino acid transporter-1 (LAT1), fatty acid transport proteins (FATP1), FATP4, and sodium/glucose cotransporter-1 (SGLT-1) in the duodenum, and the occludin-1 and CAT-1 in the jejunum upon ETEC challenge (p < 0.05). Conclusions: These results suggested that BGL can attenuate intestinal damage in weaned pigs upon ETEC challenge, which was connected with the suppressed secretion of inflammatory cytokines and enhanced serum immunoglobulins, as well as improved intestinal epithelium functions and microbiota. Full article
(This article belongs to the Special Issue Green Antimicrobials)
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15 pages, 2274 KiB  
Article
Gelidiales Are Not Just Agar—Revealing the Antimicrobial Potential of Gelidium corneum for Skin Disorders
by Margarida Matias, Susete Pinteus, Alice Martins, Joana Silva, Celso Alves, Teresa Mouga, Helena Gaspar and Rui Pedrosa
Antibiotics 2022, 11(4), 481; https://doi.org/10.3390/antibiotics11040481 - 5 Apr 2022
Cited by 8 | Viewed by 2610
Abstract
In recent decades, seaweeds have proven to be an excellent source of bioactive molecules. Presently, the seaweed Gelidium corneum is harvested in a small area of the Portuguese coast exclusively for agar extraction. The aim of this work was to fully disclosure Gelidium [...] Read more.
In recent decades, seaweeds have proven to be an excellent source of bioactive molecules. Presently, the seaweed Gelidium corneum is harvested in a small area of the Portuguese coast exclusively for agar extraction. The aim of this work was to fully disclosure Gelidium corneum as a sustainable source of antimicrobial ingredients for new dermatological formulations, highlighting its potential to be explored in a circular economy context. For this purpose, after a green sequential extraction, these seaweed fractions (F1–F5) were chemically characterized (1H NMR) and evaluated for their antimicrobial potential against Staphylococcus aureus, Staphylococcus epidermidis and Cutibacterium acnes. The most active fractions were also evaluated for their effects on membrane potential, membrane integrity and DNA damage. Fractions F2 and F3 displayed the best results, with IC50 values of 16.1 (7.27–23.02) μg/mL and 51.04 (43.36–59.74) μg/mL against C. acnes, respectively, and 53.29 (48.75–57.91) μg/mL and 102.80 (87.15–122.30) μg/mL against S. epidermidis, respectively. The antimicrobial effects of both fractions seem to be related to membrane hyperpolarization and DNA damage. This dual mechanism of action may provide therapeutic advantages for the treatment of skin dysbiosis-related diseases. Full article
(This article belongs to the Special Issue Green Antimicrobials)
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Review

Jump to: Editorial, Research

19 pages, 1361 KiB  
Review
Green Antimicrobials as Therapeutic Agents for Diabetic Foot Ulcers
by Ines D. Teixeira, Eugenia Carvalho and Ermelindo C. Leal
Antibiotics 2023, 12(3), 467; https://doi.org/10.3390/antibiotics12030467 - 25 Feb 2023
Cited by 3 | Viewed by 2367
Abstract
Diabetic foot ulcers (DFU) are one of the most serious and devastating complications of diabetes and account for a significant decrease in quality of life and costly healthcare expenses worldwide. This condition affects around 15% of diabetic patients and is one of the [...] Read more.
Diabetic foot ulcers (DFU) are one of the most serious and devastating complications of diabetes and account for a significant decrease in quality of life and costly healthcare expenses worldwide. This condition affects around 15% of diabetic patients and is one of the leading causes of lower limb amputations. DFUs generally present poor clinical outcomes, mainly due to the impaired healing process and the elevated risk of microbial infections which leads to tissue damage. Nowadays, antimicrobial resistance poses a rising threat to global health, thus hampering DFU treatment and care. Faced with this reality, it is pivotal to find greener and less environmentally impactful alternatives for fighting these resistant microbes. Antimicrobial peptides are small molecules that play a crucial role in the innate immune system of the host and can be found in nature. Some of these molecules have shown broad-spectrum antimicrobial properties and wound-healing activity, making them good potential therapeutic compounds to treat DFUs. This review aims to describe antimicrobial peptides derived from green, eco-friendly processes that can be used as potential therapeutic compounds to treat DFUs, thereby granting a better quality of life to patients and their families while protecting our fundamental bio-resources. Full article
(This article belongs to the Special Issue Green Antimicrobials)
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15 pages, 634 KiB  
Review
Antiseptic Agents for Chronic Wounds: A Systematic Review
by Koko Barrigah-Benissan, Jérôme Ory, Albert Sotto, Florian Salipante, Jean-Philippe Lavigne and Paul Loubet
Antibiotics 2022, 11(3), 350; https://doi.org/10.3390/antibiotics11030350 - 6 Mar 2022
Cited by 14 | Viewed by 5315
Abstract
In many parts of the world, antiseptic agents remain non-indicated in chronic wound care. In the current context of bacterial resistance to antibiotics and the development of new-generation antiseptic agents, wound antisepsis represents an asset for the prevention of wound infection. We aimed [...] Read more.
In many parts of the world, antiseptic agents remain non-indicated in chronic wound care. In the current context of bacterial resistance to antibiotics and the development of new-generation antiseptic agents, wound antisepsis represents an asset for the prevention of wound infection. We aimed to evaluate four common antiseptic agents in chronic wound care complete healing. The review protocol was based on the Cochrane Handbook for Systematic Reviews of Intervention and devised in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) statement guidelines. Five databases and three clinical trials registries were searched from inception to 30 June 2021 without language restrictions. We included randomised trials evaluating the efficacy of antiseptic agents in chronic wound care in adults. Interventions considered were those using antiseptics for cleansing or within a dressing. Risk of bias was assessed using the bias excel tool provided by the Bristol Academy. Evidence quality was assessed using Grading of Recommendation Assessment, Development and Evaluation (GRADE) criteria. Of 838 studies, 6 were finally included, with a total of 725 patients. The included studies assessed iodine (cadexomer or povidone iodine) (n = 3), polyhexanide (n = 2), and octenidine (n = 1). Limited evidence suggested a better wound healing completion with iodine compared to saline (two randomised controlled trials (RCT), 195 patients, pooled RR 1.85 (95%CI (1.27 to 2.69)), moderate-quality evidence). There was not enough evidence to suggest a difference in wound healing using octenidine or polyhexamide. None of the antiseptic agents influenced adverse event occurrence compared to saline. Full article
(This article belongs to the Special Issue Green Antimicrobials)
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