Antimicrobial Effects Research Articles

Evaluation of the antimicrobial activity of chemical and herbal toothpastes on selected clinical microbial oral flora

Background: Microbes are most commonly found associated with oral diseases. Globally, researchers along with the world Health Organization (WHO) suggested that this could be due to poor oral health and encourage all individuals to practice good oral hygiene using daily oral health products. The study aimed to determine the antimicrobial effects of toothpastes, as acclaimed by the manufacturers, to selected microbial flora involved in oral infections. Methodology: The antimicrobial activity of 6 toothpastes (3 herbal and 3 chemical) was tested against 3 clinical microbial isolates; Staphylococcus aureus, Escherichia coli and Candida albicans, with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of each toothpaste determined for each microbial isolate using the broth dilution method. Results: Colgate exhibited the highest inhibitory activity against S. aureus with respective MIC and MBC of 125mg/ml and 125mg/ml, followed by Oral-B with MIC and MBC of 125mg/ml and 500mg/ml, Dabur herbal with MIC and MBC of 250mg/ml and 500mg/ml, and Longrich with MIC of 500mg/ml and MBC of 1000mg/ml. Colgate and CloseUp exhibited highest inhibitory activity against E. coli with respective MIC and MBC of 125mg/ml and 500mg/ml, followed by Dabur herbal with MIC of 500mg/ml but no MBC. Colgate exhibited the highest inhibitory activity against C. albicans with respective MIC and MBC of 125mg/ml and 500mg/ml, followed by CloseUp with MIC of 500mg/ml, Longrich with MIC of 500mg/ml and MBC of 1000mg/ml, and oral-B with MIC of 500mg/ml but no MBC. Longrich and Oral-B exhibited no MIC/MBC against E. coli while Gavia charcoal exhibited no MIC/MBC against all the 3 microbial isolates at the concentrations used in the assay.Conclusion: The results obtained showed that chemically formulated toothpastes (Colgate, CloseUp and Oral-B) had higher inhibitory activity on microbial isolates than herbal toothpastes (Longrich, Dabur herbal and Gavia charcoal). This supports the manufacturers claim for the chemical toothpastes used, however, the herbal toothpastes showed little or no inhibitory effects on the microbial flora.

Efficacy of graphene nanocomposites for air disinfection in dental clinics: A randomized controlled study.

Aerosols containing disease-causing microorganisms are produced during oral diagnosis and treatment can cause secondary contamination. To investigate the use of graphene material for air disinfection in dental clinics by leveraging its adsorption and antibacterial properties. Patients who received ultrasonic cleaning at our hospital from April 2023 to April 2024. They were randomly assigned to three groups (n = 20 each): Graphene nanocomposite material suction group (Group A), ordinary filter suction group (Group B), and no air suction device group (Group C). The air quality and air colony count in the clinic rooms were assessed before, during, and after the procedure. Additionally, bacterial colony counts were obtained from the air outlets of the suction devices and the filter screens in Groups A and B. Before ultrasonic cleaning, no significant differences in air quality PM2.5 and colony counts were observed among the three groups. However, significant differences in air quality PM2.5 and colony counts were noted among the three groups during ultrasonic cleaning and after ultrasonic treatment. Additionally, the number of colonies on the exhaust port of the suction device and the surface of the filter were significantly lower in Group A than in Group B (P = 0.000 and P = 0.000, respectively). Graphene nanocomposites can effectively sterilize the air in dental clinics by exerting their antimicrobial effects and may be used to reduce secondary pollution.

Assessment of the Efficacy of Indigenously Prepared Azadirachta Indica Mouthwash on P. Gingivalis in Chronic Periodontitis Patients: A Microbiological Study

Aim: The present study aimed to compare and evaluate the antimicrobial effect of Azadirachta Indica (Neem mouthwash) to chlorhexidine mouthwash on P. gingivalis. Materials ans Methods: The subjects were divided into 2 groups. Group I included 5 subjects who used self-prepared neem mouthwash, and Group II included 5 subjects who used 0.2% chlorhexidine mouthwash. Subgingival plaque samples were taken at baseline and the 15th day after using the mouthwash and subjected to microbiological evaluation. Results: The colony forming unit (CFU) of P. gingivalis was calculated at baseline and on the 15th day after using mouthwash using the digit colony counter. A comparison of the total CFU of both mouthwashes revealed that the neem mouth was effective in reducing the microbial colonies of P. gingivalis from baseline to the 15th day. Conclusion: It was concluded that the self-prepared neem mouthwash was effective in reducing the colony-forming unit of P. gingivalis in the sub-gingival plaque samples and showed better results than the commercially available chemical-based chlorhexidine mouthwash.

Synthesis, Physicochemical Characterization, and Antimicrobial Evaluation of Halogen-Substituted Non-Metal Pyridine Schiff Bases

Four synthetic Schiff bases (PSB1 [(E)-2-(((4-aminopyridin-3-yl)imino)methyl)-4,6-dibromophenol], PSB2 [(E)-2-(((4-aminopyridin-3-yl)imino)methyl)-4,6-diiodophenol], PSB3 [(E)-2-(((4-aminopyridin-3-yl)imino)methyl)-4-iodophenol], and PSB4 [(E)-2-(((4-aminopyridin-3-yl)imino)methyl)-4-chloro-6-iodophenol]) were fully characterized. These compounds exhibit an intramolecular hydrogen bond between the hydroxyl group of the phenolic ring and the nitrogen of the azomethine group, contributing to their stability. Their antimicrobial activity was evaluated against various Gram-negative and Gram-positive bacteria, and it was found that the synthetic pyridine Schiff bases, as well as their precursors, showed no discernible antimicrobial effect on Gram-negative bacteria, including Salmonella Typhi (and mutant derivatives), Salmonella Typhimurium, Escherichia coli, and Morganella morganii. In contrast, a more pronounced biocidal effect against Gram-positive bacteria was found, including Bacillus subtilis, Streptococcus agalactiae, Streptococcus pyogenes, Enterococcus faecalis, Staphylococcus aureus, and Staphylococcus haemolyticus. Among the tested compounds, PSB1 and PSB2 were identified as the most effective against Gram-positive bacteria, with PSB2 showing the most potent biocidal effects. Although the presence of reactive oxygen species (ROS) was noted after treatment with PSB2, the primary mode of action for PSB2 does not appear to involve ROS generation. This conclusion is supported by the observation that antioxidant treatment with vitamin C only partially mitigated bacterial inhibition, indicating an alternative biocidal mechanism.

Effects of Bacteriocin Extracted from Lactobacillus plantarum on Treatment-Resistant Escherichia coli Bacteria Isolated from Humans and Livestock

Background: Lactic acid bacteria (LAB) are among the most common probiotics and play a significant role in promoting health within the human intestinal microbiota. Their protective functions in the intestine include producing antimicrobial compounds, regulating the balance of the intestinal microbiome, and more. Objectives: This study aims to investigate the antimicrobial effects of bacteriocin extracted from Lactobacillus plantarum (L. plantarum) on Escherichia coli (E. coli) strains that cause treatment-resistant urinary tract infections (UTIs) in humans and mastitis in livestock. Methods: Twenty E. coli isolates were obtained from patients with UTIs and cows with mastitis. After culturing the samples on Eosin-methylene blue, McConkey agar, and blood agar, the strains were identified using biochemical tests. Bacteriocin produced by L. plantarum ATCC8014 was extracted, and its concentration was measured using the Bradford method. The antimicrobial effect of the bacteriocin was assessed using the broth microdilution method to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Additionally, the bacteriocin's antimicrobial activity was evaluated through three repetitions of disk diffusion and agar well diffusion methods. Results: The findings revealed that the MIC and MBC concentrations for all human and animal strains were 13.38 μg/mL and 26.76 μg/mL, respectively. Notably, two animal samples (No. 3 and No. 10) and one human sample (No. 6) showed lower MIC and MBC concentrations compared to the other samples and the standard E. coli sample. However, all strains were resistant to bacteriocin in the disk diffusion and agar well diffusion methods. Conclusions: The data indicate a high risk of increasing treatment-resistant E. coli strains in UTIs and livestock, which could pose a significant threat to public and animal health. Therefore, it is essential to further investigate the effects of different bacteriocins on these resistant strains, in conjunction with antibiotic therapies.

Antimicrobial and antibiofilm effect of promethazine on bacterial isolates from canine otitis externa: an in vitro study

Otitis externa is an inflammatory disease of the external ear canal of complex and multifactorial etiology associated with recurrent bacterial infection. This study aimed to assess the antimicrobial and antibiofilm activity of promethazine against bacterial isolates from dogs with otitis externa, as well as the effect of this compound on the dynamics of biofilm formation over 120 h. Planktonic bacterial susceptibility to promethazine was evaluated to determine the minimum inhibitory concentrations (MIC). The minimum biofilm eradication concentration (MBEC) was also determined by broth microdilution. To evaluate the effect on biofilm growth, promethazine was tested at three concentrations MIC, MIC/2 and MIC/8, with daily readings at 48, 72, 96 and 120 h. The MICs of promethazine ranged from 48.83 to 781.25 μg mL−1. Promethazine significantly (P < 0.05) reduced mature biofilm biomass, with MBECs ranging from 48.8 to 6250 μg mL−1 and reduced (P < 0.01) biofilm formation for up to the 120-h, at concentrations corresponding to the MIC obtained against each isolate. Promethazine was effective against microorganisms associated with canine otitis externa. The data suggest that promethazine presents antimicrobial and antibiofilm activity and is a potential alternative to treat and prevent recurrent bacterial otitis in dogs. These results emphasize the importance of drug repurposing in veterinary otology as an alternative to reduce antimicrobial resistance.

Synergistic bactericidal activity of chlorhexidine loaded on positively charged ionic liquid-protected silver nanoparticles as a root canal disinfectant against Enterococcus faecalis: An ex vivo study

The advancement of nanotechnology and the development of nanocomplexes offer promising solutions to address the limitations in biofilm management within endodontics. Current cleaning and disinfection methods often fail to completely eliminate bacterial biofilms from the complex anatomical structures of root canals, making the invention of new disinfectants or disinfection methods highly relevant. Previously, chlorhexidine-loaded positively charged ionic liquid-protected silver nanoparticles (CHX@AgNPs⁺) were introduced as an innovative root canal irrigation solution, demonstrating significant antibacterial efficacy against Enterococcus faecalis in vitro. This study aimed to further evaluate the antibiofilm activity of CHX@AgNPs⁺ in the root canals of extracted human teeth contaminated with E. faecalis biofilm. Fifty single-rooted human teeth with mature apices were randomly assigned to five experimental groups based on the irrigants used: CHX@AgNPs⁺, AgNPs⁺, 2.5 % NaOCl, 2 % CHX, and normal saline (n = 10 per group). The root canals were contaminated with E. faecalis, and biofilm formation was confirmed. Initial sampling (S1) was performed, followed by mechanical preparation of the root canals using ProTaper F3 files and irrigation with the respective test solutions. Post-instrumentation sampling (S2) was then conducted. The results demonstrated that CHX@AgNPs⁺ exhibited antibiofilm properties comparable to 2.5 % NaOCl, with no significant difference between them. Additionally, CHX@AgNPs⁺ significantly enhanced antimicrobial efficacy compared to CHX alone (P < 0.05), highlighting its potential as an effective root canal disinfectant.

Sensory testing and quality maintenance of hamburgers containing soybean meat

In the past few years, lifestyle-related diseases have been increasing, and meat intake has been linked to this increase. Therefore, in recent years, there have been attempts to use soybeans as a substitute for meat. Soybeans exhibit antioxidant and antimicrobial effects. Therefore, processing foods using soybeans may preserve food quality because the main factors causing food deterioration are oxidation and microbial growth. To verify the quality-retention effect of soybeans, we conducted a sensory test on hamburgers, the quality of which readily deteriorates over time. We investigated the percentage of soybean meat that would be acceptable in a hamburger and quality retention with the addition of different amounts of soybean meat. We found that hamburgers with soybean meat were accepted by more than half of the participants when the soybean meat content was ≤50%. In terms of changes over time in quality-related factors, the L- and b-values (lightness/brightness and yellowness/blueness, respectively) were higher, avalue (redness/greenness) was lower, and pH was higher in hamburgers that contained soybean meat than in those without added soybean meat. Furthermore, an increase in the bacteria count and peroxide content was suppressed in hamburgers containing soybean meat. The results indicate that hamburgers containing soybean meat are of higher quality than those made with 100% animal meat. The use of soybeans as a meat substitute in hamburgers can help mitigate the rise of lifestyle-related diseases linked to high meat consumption.

Methods for Determination of Antimicrobial Activity of Essential Oils In Vitro-A Review.

Essential oils (EOs) have been gaining popularity in the past decades among researchers due to their potential to replace conventional chemicals used in the fight against pests, pathogenic and spoilage microbes, and oxidation processes. EOs are complex mixtures with many chemical components, the content of which depends on many factors-not just the plant genus, species, or subspecies, but also chemotype, locality, climatic conditions, phase of vegetation, method of extraction, and others. Due to this fact, there is still much to study, with antimicrobial effect being one of the key properties of EOs. There are many methods that have been frequently used by researchers for in vitro evaluation; however, although the research has been going on for decades, an internationally accepted standard is still missing. Most of methods are based on time-proven standards used for the testing of antibiotics. Due to the specific properties of EOs and their components, such as volatility and hydrophobicity, many modifications of these standard procedures have been adopted. The aim of this review is to describe the most common methods and their modifications for the testing of antimicrobial properties of EOs and to point out the most controversial variables which can potentially affect results of the assays.

Evaluation of antibacterial and anticancer properties of secondary metabolites isolated from soil Bacillus spp focusing on two strains of Bacillus licheniformis and Bacillus siamensis

BackgroundBacillus strains are well recognized for their inherent production of bioactive compounds that exhibit antibacterial and anticancer properties. This study aims to evaluate the antimicrobial and anticancer effects of the secondary metabolite isolated from Bacillus licheniformis and Bacillus siamensis strain.Material and methodWe developed and purified a new soil-derived Bacillus strain to study its metabolites on cancer cells and bacteria. After evaluating the antimicrobial effects of the selected strains’ secondary metabolites by well diffusion, growth conditions and temperature optimised using liquid-liquid extraction, secondary metabolites isolated, and active compounds identified using GC-MS. Evaluation of PC-3 and HPrEpC cytotoxicity. AV/PI staining and comet assay assessed necrosis and apoptosis. Real-time PCR measured apoptotic gene expression. Finally, the scratch test measured cell movement.ResultsBacillus strain metabolites exhibit dual-purpose antimicrobial and anticancer properties. Bacillus licheniformis isolate 56 and S2-G12 isolate 60 demonstrated the greatest antibacterial activity. Among all Bacillus isolates, isolates 56 (Bacillus licheniformis) and 60 (Bacillus siamensis strain) had the highest antibacterial activity. Crude extracts obtained from strains 56 and 60 decreased PC-3 cell viability in a dose-dependent manner. At 200 µg/mL, the survival rate of cells treated with strain 56 and 60 crude extract was 23% and 25%, respectively (p < 0.001). The treatment of PC-3 cells with strains 56 and 60 crude extract led to considerable apoptosis (46.2% and 50.09%, respectively) compared to the control group. After treatment with the crude extract from strains 56 and 60 at an IC50 concentration, a significant number of PC-3 cells showed comet formation, indicating DNA fragmentation. Metabolites extracted from strain 56 and 60 enhanced caspase 3, caspase 8, and Bax genes expression and reduced Bcl-2 expression (p < 0.001). Cell migration was also prevented.ConclusionOur findings show that the secondary metabolites of B. licheniformis and B. siamensis have antibiotic and anticancer properties. However in vivo studies are necessary to confirm these findings.

Investigating antimicrobial and antioxidant activity of liquid smoke and physical-chemical stability of bacon subjected to liquid smoke and conventional smoking.

Liquid smoke, an alternative to traditional wood burning smoking, enhances product value by imparting desirable characteristics such as aroma, flavor, and color. Furthermore, it contains components with inherent antimicrobial and antioxidant properties. This study compares the effects of liquid smoke and conventional smoking methods in bacon processing. Over a 90-day storage period at 22°C, physical-chemical stability, sensory attributes, and microbiological characteristics of the bacon were evaluated. The antimicrobial and antioxidant properties of liquid smoke were assessed. Liquid smoke exhibited antioxidant activity, with an inhibitory concentration (IC50) value of 0.19mg/mL, indicating the concentration of the extract needed to inhibit 50% of DPPH (2,2'-diphenyl-1-picrylhydrazyl) radicals. Moreover, it demonstrated antimicrobial effects against Escherichia coli, Salmonella choleraesius, Staphylococcus aureus, and Listeria monocytogenes, with a minimum bactericidal concentration ranging from 7.5% to 10%. Throughout the storage, bacon treated with liquid smoke showed no signs of rancid odor, supported by thiobarbituric acid reactive substances values below 0.85mgMDA/kg (where MDA is malondialdehyde). The utilization of liquid smoke yielded visually attractive bacon with enhanced color attributes, including a distinct yellow and red hue, as well as increased luminosity and brightness, surpassing the effects of traditional smoke. Remarkably, liquid smoke application significantly reduced processing time from 30h to approximately 5h, leading to substantial cost savings in the processing phase.

The Influence of the Functional Group on the Physicochemical and Biological Properties of New Phenanthro[9,10-d]-Imidazole Derivatives.

The search for safe, cheap, and repeatable diagnostic methods is a fundamental research goal. Currently, great hope is placed on fluorescence imaging. However, the development of this method mainly depends on efficient fluorescent probes. Designing and obtaining new probes with potential applications in fluorescence imaging is very difficult because compounds of this type must meet several requirements related to their properties. Therefore, this article attempted to obtain and study new phenanthro[9,10-d]-imidazole derivatives (PK1-PK3) with potential application as fluorescent probes for fluorescence imaging. The main goal of the work was to assess the effect of two functional groups (such as the formyl group (PK2) and rhodanine-3-acetic acid (PK3)) on selected physicochemical properties and possibilities of practical application of the considered compounds. The conducted studies proved that the influence of the functional group is significant, as it causes a bathochromic shift in both absorption and emission results (by the order PK1 < PK2 < PK3). Moreover, all compounds could stain live cells cultured in vitro. The staining efficiency was not affected by the cell line, thanks to which we obtained the correct staining of both mouse and human cell lines. PK3 was the most attractive of the tested compounds due to its staining potential of live cells and retention after fixation. Our results also showed some antibacterial and antifungal activity of the newly synthesized compounds (PK1-PK3). Among them, PK3 showed the highest antimicrobial effect, especially against Gram-positive bacteria.

An Innovative Approach: The Usage of N-Acetylcysteine in the Therapy of Pneumonia in Neonatal Calves

NAC has mucolytic, antioxidant, and antimicrobial effects in living organisms. However, the therapeutic effects of NAC on clinical recovery among neonatal calves with respiratory diseases have not yet been studied. Our study represents the first investigation of the effects of NAC in neonatal calves with pneumonia. The objective of this work was to observe the effects of NAC in the treatment of neonatal pneumonia, including its ability to reduce the clinical score, shorten the duration of the treatment, and improve the overall health condition of neonatal calves. For this study, calves were divided into two groups: a treatment group that received NAC and amoxicillin with clavulanic acid, and a control group that received amoxicillin with clavulanic acid (antimicrobial only). The findings of this study indicate that NAC treatment significantly shortened the time to resolution (p &lt; 0.001), compared to the results in the group without NAC treatment. Generally, NAC-supplemented therapy reduced the recovery time by more than 27 h (or slightly more than one day), compared to that in the antimicrobial-only group. Our study presents the first reported usage of NAC in therapy for respiratory disorders.

Inhibition of Streptococcus pyogenes biofilm by Lactiplantibacillus plantarum and Lacticaseibacillus rhamnosus.

The human pathobiont Streptococcus pyogenes forms biofilms and causes infections, such as pharyngotonsillitis and necrotizing fasciitis. Bacterial biofilms are more resilient to antibiotic treatment, and new therapeutic strategies are needed to control biofilm-associated infections, such as recurrent pharyngotonsillitis. Lactiplantibacillus plantarum and Lacticaseibacillus rhamnosus are two bacterial commensals used for their probiotic properties. This study aimed to elucidate the anti-biofilm properties of L. plantarum and L. rhamnosus cell-free supernatants (LPSN and LRSN, respectively) on S. pyogenes biofilms grown in vitro in supplemented minimal medium. When planktonic or biofilm S. pyogenes were exposed to LPSN or LRSN, S. pyogenes survival was reduced significantly in a concentration-dependent manner, and the effect was more pronounced on preformed biofilms. Enzymatic digestion of LPSN and LRSN suggested that glycolipid compounds might cause the antimicrobial effect. In conclusion, this study indicates that L. plantarum and L. rhamnosus produce glycolipid bioactive compounds that reduce the viability of S. pyogenes in planktonic and biofilm cultures.IMPORTANCEStreptococcus pyogenes infections are a significant concern for populations at risk, such as children and the elderly, as non-invasive conditions such as impetigo and strep throat can lead to severe invasive diseases such as necrotizing fasciitis. Despite its susceptibility to current antibiotics, the formation of biofilm by this pathogen decreases the efficacy of antibiotic treatment alone. The ability of commensal lactobacillus to kill S. pyogenes has been documented by previous studies using in vitro settings. The relevance of our study is in using a physiological setup and a more detailed understanding of the nature of the lactobacillus molecule affecting the viability of S. pyogenes. This additional knowledge will help for a better comprehension of the molecules' characteristics and kinetics, which in turn will facilitate new avenues of research for its translation to new therapies.

Cytotoxic Effects of Biosynthesized zinc nanoparticles on Normal fibroblast cells and their antimicrobial effect on pathogenic strains

Nanoparticles, particularly zinc nanoparticles (ZnNPs), have garnered substantial interest in biomedical research for their potential applications in therapeutics and antimicrobial therapy. In this study, we investigated the cytotoxic effects of biosynthesized zinc nanoparticles on normal fibroblast cells and evaluated their antimicrobial efficacy against pathogenic strains. The biosynthesis of zinc nanoparticles was achieved through an eco-friendly and cost-effective approach utilizing biological agents. The cytotoxicity of biosynthesized zinc nanoparticles was assessed on normal fibroblast cells, serving as a model for evaluating biocompatibility. Our results indicate that biosynthesized zinc nanoparticles exhibited minimal cytotoxicity towards normal fibroblast cells, suggesting their potential safety for biomedical applications. Furthermore, the antimicrobial activity of biosynthesized zinc nanoparticles was evaluated against pathogenic strains, including antibiotic-resistant bacteria. The antimicrobial efficacy of zinc nanoparticles demonstrated promising results, highlighting their potential as alternative antimicrobial agents. Overall, this study provides valuable insights into the cytotoxic effects of biosynthesized zinc nanoparticles on normal fibroblast cells and underscores their antimicrobial potential against pathogenic strains, offering opportunities for the development of nanoparticle-based therapeutics and antimicrobial agents in medicine and healthcare.

Nanocomposites: silver nanoparticles and bacteriocins obtained from lactic acid bacteria against multidrug-resistant Escherichia coli and Staphylococcus aureus.

Drug-resistant bacteria such as Escherichia coli and Staphylococcus aureus represent a global health problem that requires priority attention. Due to the current situation, there is an urgent need to develop new, more effective and safe antimicrobial agents. Biotechnological approaches can provide a possible alternative control through the production of new generation antimicrobial agents, such as silver nanoparticles (AgNPs) and bacteriocins. AgNPs stand out for their antimicrobial potential by employing several mechanisms of action that can act simultaneously on the target cell such as the production of reactive oxygen species and cell wall rupture. On the other hand, bacteriocins are natural peptides synthesized ribosomally that have antimicrobial activity and are produced, among others, by lactic acid bacteria (LAB), whose main mechanism of action is to produce pores at the level of the cell membrane of bacterial cells. However, these agents have disadvantages. Nanoparticles also have limitations such as the tendency to form aggregates, which decreases their antibacterial activity and possible cytotoxic effects, and bacteriocins have a narrow spectrum of action, require high doses to be effective, and can be degraded by proteases. Given these limitations, nanoconjugates of these two agents have been developed that can act synergistically in the control of pathogenic bacteria resistant to antibiotics. This review focuses on knowing relevant aspects of the antibiotic resistance of E. coli and S. aureus, the characteristics of these new generation antibacterial agents, and their effect alone or forming nanoconjugates that are more effective against the multiresistant mentioned bacteria.

A randomized controlled non-inferiority trial of placebo versus macrolide antibiotics for Mycoplasma pneumoniae infection in children with community-acquired pneumonia: trial protocol for the MYTHIC Study

BackgroundMycoplasma pneumoniae is a major cause of community-acquired pneumonia (CAP) in school-aged children. Macrolides are the first-line treatment for this infection. However, it is unclear whether macrolides are effective in treating M. pneumoniae CAP, mainly due to limitations in microbiological diagnosis of previous studies. The extensive global use of macrolides has led to increasing antimicrobial resistance. The overall objective of this trial is to produce efficacy data for macrolide treatment in children with M. pneumoniae CAP.MethodsThe MYTHIC Study is a randomized, double-blind, placebo-controlled, multicenter, non-inferiority trial in 13 Swiss pediatric centers. Previously healthy ambulatory and hospitalized children aged 3–17 years with clinically diagnosed CAP will be screened with a sensitive and commercially available M. pneumoniae-specific IgM lateral flow assay from capillary blood. Mycoplasma pneumoniae infection in screened patients will be verified retrospectively by respiratory PCR (reference test) and IgM antibody-secreting cell enzyme-linked immunospot (ELISpot) assay (confirmatory test for distinguishing between carriage and infection). Patients will be randomized 1:1 to receive a 5-day treatment of macrolides (azithromycin) or placebo. The co-primary endpoints are (1) time to normalization of all vital signs, including body temperature, respiratory rate, heart rate, and saturation of peripheral oxygen (efficacy), and (2) CAP-related change in patient care status (i.e., admission, re-admission, or intensive care unit transfer) within 28 days (safety). Secondary outcomes include adverse events (AEs), as well as antimicrobial and anti-inflammatory effects. For both co-primary endpoints, we aim to show non-inferiority of placebo compared to macrolide treatment. We expect no macrolide effect (hazard ratio of 1, absolute risk difference of 0) and set the corresponding non-inferiority margins to 0.7 and −7.5%. The “at least one” success criterion is used to handle multiplicity with the two co-primary endpoints. With a power of 80% to reject at least one null hypothesis at a one-sided significance level of 1.25%, 376 patients will be required.DiscussionThis trial will produce efficacy data for macrolide treatment in children with M. pneumoniae CAP that might help to reduce the prescription of antibiotics and therefore contribute to the global efforts toward reducing antimicrobial resistance.Trial registrationClinicalTrials.gov, NCT06325293. Registered on 24 April 2024

Exploring the Potential of Macroalgae for Sustainable Crop Production in Agriculture.

Marine macroalgae, which typically colonize coastal areas, are simple plant organisms. They live on rocks in coastal regions and are classified into red, brown, and green macroalgae. These algae are an important natural resource in agriculture due to their ability to enhance the structural, chemical, and biological properties of soil. Marine macroalgae can be used to produce various biocidal molecules that are effective in controlling plant pathogens. Much of the literature on marine macroalgae and their derivatives focuses primarily on the pharmaceutical field, while their use in agriculture is still considered secondary. However, various studies and experiments have demonstrated their potential to play a significant role in crop protection and enhancement. This review aims to highlight the various applications of macroalgae in plant production. It also emphasizes the biotechnological importance of marine macroalgae derivatives as biofertilizers, molecules for controlling insects and microorganisms, and as plant growth conditioners. Compounds from macroalgae, such as fatty acids, carotenoids, polyphenols, and carbohydrates, are being investigated for their fungicidal, antimicrobial, and antiviral effects against various plant pathogens. Beyond enhancing crop production, macroalgae can also be considered multifunctional bioinoculants suitable for use in organic farming.

Bioactive Potential of Algae and Algae-Derived Compounds: Focus on Anti-Inflammatory, Antimicrobial, and Antioxidant Effects.

Algae, both micro- and macroalgae, are recognized for their rich repository of bioactive compounds with potential therapeutic applications. These marine organisms produce a variety of secondary metabolites that exhibit significant anti-inflammatory, antioxidant, and antimicrobial properties, offering promising avenues for the development of new drugs and nutraceuticals. Algae-derived compounds, including polyphenols, carotenoids, lipids, and polysaccharides, have demonstrated efficacy in modulating key inflammatory pathways, reducing oxidative stress, and inhibiting microbial growth. At the molecular level, these compounds influence macrophage activity, suppress the production of pro-inflammatory cytokines, and regulate apoptotic processes. Studies have shown that algae extracts can inhibit inflammatory signaling pathways such as NF-κB and MAPK, reduce oxidative damage by activating Nrf2, and offer an alternative to traditional antibiotics by combatting bacterial infections. Furthermore, algae's therapeutic potential extends to addressing diseases such as cardiovascular disorders, neurodegenerative conditions, and cancer, with ongoing research exploring their efficacy in preclinical animal models. The pig model, due to its physiological similarities to humans, is highlighted as particularly suitable for validating the bioactivities of algal compounds in vivo. This review underscores the need for further investigation into the specific mechanisms of action and clinical applications of algae-derived biomolecules.

Unlocking the potential of lactic acid bacteria mature biofilm extracts as antibiofilm agents

The continuous growth of biofilm infections and their resilience to conventional cleaning methods and antimicrobial agents pose a worldwide challenge across diverse sectors. This persistent medical, industrial, and environmental issue contributes to treatment challenges and chronic diseases. Lactic acid bacteria have garnered global attention for their substantial antimicrobial effects against pathogens and established beneficial roles. Notably, their biofilms are also predicted to show a promising control strategy against pathogenic biofilm formation. The prevalence of biofilm-related problems underscores the need for extensive research and innovative solutions to tackle this global challenge. This novel study investigates the effect of different extracts (external, internal, and mixed extracts) obtained from Lactobacillus rhamnosus GG biofilm on pathogenic-formed biofilms. Subsequently, external extracts presented an important eradication effectiveness. Furthermore, a 6-fold concentration of these extracts led to eradication percentages of 57%, 67%, and 76% for Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa biofilms, respectively, and around 99.9% bactericidal effect of biofilm cells was observed for the three strains. The results of this research could mark a significant breakthrough in the field of anti-biofilm and antimicrobial strategies. Further studies and molecular research will be necessary to detect the molecules secreted by the biofilm, and their mechanisms of action engaged in new anti-biofilm strategies.