In vitro experimental conditions and tools can influence the safety and biocompatibility results of antimicrobial electrospun biomaterials for wound healing.

Electrospun (ES) fibrous nanomaterials have been widely investigated as novel biomaterials. These biomaterials have to be safe and biocompatible; hence, they need to be tested for cytotoxicity before being administered to patients. The aim of this study was to develop a suitable and biorelevant in vitro cytotoxicity assay for ES biomaterials (e.g. wound dressings). We compared different in vitro cytotoxicity assays, and our model wound dressing was made from polycaprolactone and polyethylene oxide and contained chloramphenicol as the active pharmaceutical ingredient. Baby Hamster Kidney cells (BHK-21), human primary fibroblasts and MTS assays together with real-time cell analysis were selected. The extract exposure and direct contact safety evaluation setups were tested together with microscopic techniques. We found that while extract exposure assays are suitable for the initial testing, the biocompatibility of the biomaterial is revealed in in vitro direct contact assays where cell interactions with the ES wound dressing are evaluated. We observed significant differences in the experimental outcome, caused by the experimental set up modification such as cell line choice, cell medium and controls used, conducting the phosphate buffer washing step or not. A more detailed technical protocol for the in vitro cytotoxicity assessment of ES wound dressings was developed.

Anti-Infection of Oral Microorganisms from Herbal Medicine of Piper crocatum Ruiz & Pav.

The WHO Global Status Report on Oral Health 2022 reveals that oral diseases caused by infection with oral pathogenic microorganisms affect nearly 3.5 billion people worldwide. Oral health problems are caused by the presence of S. mutans, S. sanguinis, E. faecalis and C. albicans in the oral cavity. Synthetic anti-infective drugs have been widely used to treat oral infections, but have been reported to cause side effects and resistance. Various strategies have been implemented to overcome this problem. Synthetic anti-infective drugs have been widely used to treat oral infections, but they have been reported to cause side effects and resistance. Therefore, it is important to look for safe anti-infective alternatives. Ethnobotanical and ethnopharmacological studies suggest that Red Betel leaf (Piper crocatum Ruiz & Pav) could be a potential source of oral anti-infectives. This review aims to discuss the pathogenesis mechanism of several microorganisms that play an important role in causing health problems, the mechanism of action of synthetic oral anti-infective drugs in inhibiting microbial growth in the oral cavity, and the potential of red betel leaf (Piper crocatum Ruiz & Pav) as an herbal oral anti-infective drug. This study emphasises the importance of researching natural components as an alternative treatment for oral infections that is more effective and can meet global needs.

Synthesis, fungal biotransformation, and evaluation of the antimicrobial potential of chalcones with a chlorine atom.

Chalcones are intermediate products in the biosynthesis of flavonoids, which possess a wide range of biological properties, including antimicrobial and anticancer activities. The introduction of a chlorine atom and the glucosyl moiety into their structure may increase their bioavailability, bioactivity, and pharmacological use. The combined chemical and biotechnological methods can be applied to obtain such compounds. Therefore, 2-chloro-2'-hydroxychalcone and 3-chloro-2'-hydroxychalcone were synthesized and biotransformed in cultures of two strains of filamentous fungi, i.e. Isaria fumosorosea KCH J2 and Beauveria bassiana KCH J1.5 to obtain their novel glycosylated derivatives. Pharmacokinetics, drug-likeness, and biological activity of them were predicted using cheminformatics tools. 2-Chloro-2'-hydroxychalcone, 3-chloro-2'-hydroxychalcone, their main glycosylation products, and 2'-hydrochychalcone were screened for antimicrobial activity against several microbial strains. The growth of Escherichia coli 10,536 was completely inhibited by chalcones with a chlorine atom and 3-chlorodihydrochalcone 2'-O-ß-D-(4″-O-methyl)-glucopyranoside. The strain Pseudomonas aeruginosa DSM 939 was the most resistant to the action of the tested compounds. However, chalcone aglycones and glycosides with a chlorine atom almost completely inhibited the growth of bacteria Staphylococcus aureus DSM 799 and yeast Candida albicans DSM 1386. The tested compounds had different effects on lactic acid bacteria depending on the tested species. In general, chlorinated chalcones were more effective in the inhibition of the tested microbial strains than their unchlorinated counterparts and aglycones were a little more effective than their glycosides.

Expanding the Role of Chiral Drugs and Chiral Nanomaterials as a Potential Therapeutic Tool.

Chirality, the property of molecules having mirror-image forms, plays a crucial role in pharmaceutical and biomedical research. This review highlights its growing importance, emphasizing how chiral drugs and nanomaterials impact drug effectiveness, safety, and diagnostics. Chiral molecules serve as precise diagnostic tools, aiding in accurate disease detection through unique biomolecule interactions. The article extensively covers chiral drug applications in treating cardiovascular diseases, CNS disorders, local anesthesia, anti-inflammatories, antimicrobials, and anticancer drugs. Additionally, it explores the emerging field of chiral nanomaterials, highlighting their suitability for biomedical applications in diagnostics and therapeutics, enhancing medical treatments.

Myco-fabricated silver nanoparticle by novel soil fungi from Saudi Arabian desert and antimicrobial mechanism.

Biological agents are getting a noticeable concern as efficient eco-friendly method for nanoparticle fabrication, from which fungi considered promising agents in this field. In the current study, two fungal species (Embellisia spp. and Gymnoascus spp.) were isolated from the desert soil in Saudi Arabia and identified using 18S rRNA gene sequencing then used as bio-mediator for the fabrication of silver nanoparticles (AgNPs). Myco-synthesized AgNPs were characterized using UV-visible spectrometry, transmission electron microscopy, Fourier transform infrared spectroscopy and dynamic light scattering techniques. Their antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Klebsiella pneumoniae were investigated. In atrial to detect their possible antibacterial mechanism, Sodium dodecyl sulfate (SDS-PAGE) and TEM analysis were performed for Klebsiella pneumoniae treated by the myco-synthesized AgNPs. Detected properties of the fabricated materials indicated the ability of both tested fungal strains in successful fabrication of AgNPs having same range of mean size diameters and varied PDI. The efficiency of Embellisia spp. in providing AgNPs with higher antibacterial activity compared to Gymnoascus spp. was reported however, both indicated antibacterial efficacy. Variations in the protein profile of K. pneumoniae after treatments and ultrastructural changes were observed. Current outcomes suggested applying of fungi as direct, simple and sustainable approach in providing efficient AgNPs.

Natural dyes developed by microbial-nanosilver to produce antimicrobial and anticancer textiles.

Developing special textiles (for patients in hospitals for example) properties, special antimicrobial and anticancer, was the main objective of the current work. The developed textiles were produced after dyeing by the novel formula of natural (non-environmental toxic) pigments (melanin amended by microbial-AgNPs). Streptomyces torulosus isolate OSh10 with accession number KX753680.1 was selected as a superior producer for brown natural pigment. By optimization processes, some different pigment colors were observed after growing the tested strain on the 3 media. Dextrose and malt extract enhanced the bacteria to produce a reddish-black color. However, glycerol as the main carbon source and NaNO3 and asparagine as a nitrogen source were noted as the best for the production of brown pigment. In another case, starch as a polysaccharide was the best carbon for the production of deep green pigment. Peptone and NaNO3 are the best nitrogen sources for the production of deep green pigment. Microbial-AgNPs were produced by Fusarium oxysporum with a size of 7-21 nm, and the shape was spherical. These nanoparticles were used to produce pigments-nanocomposite to improve their promising properties. The antimicrobial of nanoparticles and textiles dyeing by nanocomposites was recorded against multidrug-resistant pathogens. The new nanocomposite improved pigments' dyeing action and textile properties. The produced textiles had anticancer activity against skin cancer cells with non-cytotoxicity detectable action against normal skin cells. The obtained results indicate to application of these textiles in hospital patients' clothes.

Linalool: Therapeutic Indication And Their Multifaceted Biomedical Applications.

This comprehensive review endeavors to illuminate the nuanced facets of linalool, a prominent monoterpene found abundantly in essential oils, constituting a massive portion of their composition. The biomedical relevance of linalool is a key focus, highlighting its therapeutic attributes observed through anti-nociceptive effects, anxiolytic properties, and behavioral modulation in individuals affected by dementia. These findings underscore the compound's potential application in biomedical applications. This review further explores contemporary formulations, delineating the adaptability of linalool in nano-emulsions, microemulsions, bio-capsules, and various topical formulations, including topical gels and lotions. This review covers published and granted patents between 2018-2024 and sheds light on the evolving landscape of linalool applications, revealing advancements in dermatological, anti-inflammatory, and antimicrobial domains.

Antimicrobial management of dental infections: Updated review.

Dental infections, which include anything from severe periodontal illnesses and abscess forms to routine tooth caries, are a major public health risk. This review article focuses on the pathophysiology and treatment of dental infections. A narrative review was conducted based on several published articles, relevant journals, and books in Google Scholar PubMed using the keywords dental caries, periodontal disease, gingivitis, and related diseases; we excluded duplicated information. Our review illustrated the types of dental infections and the proper antimicrobial drug that is suitable for this disease. Drawing from recent research findings and clinical evidence, we explore the spectrum of bacteria commonly associated with dental infections and their susceptibility profiles to various antibiotics. Emphasis is placed on understanding the mechanisms of antibiotic action and resistance in the context of dental pathogens, shedding light on optimal treatment regimens and potential challenges in clinical management. Additionally, we go over the clinical consequences of antibiotic therapy in dentistry, taking into account factors like patient selection, dose guidelines, and side effects. The management of dental infections through antimicrobial strategies has undergone significant advancements, as evidenced by this updated review. Besides the normal methods, emerging technologies such as 3D printing for drug delivery of antibiotics and disinfectants hold promise in enhancing treatment efficacy and patient outcomes. By leveraging the precision and customization afforded by 3D printing, dentistry can tailor antimicrobial interventions to individual patient needs, optimizing therapeutic outcomes while minimizing adverse effects.

Medicinal Potential of the Giant Puffball Mushroom Calvatia gigantea (Agaricomycetes): A Review.

Calvatia gigantea, commonly known as the giant puffball mushroom, has traditionally been regarded as a significant edible and medicinal species due to its wide spectrum of bioactive compounds and its health-promoting properties. This study aims to systematize the knowledge on the nutritional value and therapeutic potential of C. gigantea, highlighting its role in traditional and contemporary medicine. The mushroom is recognized for its nutritional content, including easily digestible protein, carbohydrates, fiber, phenolic compounds, vitamins, and minerals, while being low in calories, cholesterol, and sodium. Furthermore, C. gigantea exhibits a range of biological effects, such as antioxidant, anticancer, antimicrobial, antidiabetic, and wound-healing properties, attributed to its diverse chemical composition that includes unsaturated fatty acids, free amino acids, polysaccharides, and bioactive metabolites.

Editorial: The Global Threats of Increasing Antimicrobial Resistance Require New Approaches to Drug Development, Including Molecular Antimicrobial Adjuvants.

Antimicrobial resistance and the associated morbidity and mortality from untreatable common infectious organisms is an increasing threat to global public health. In 2019, the Antimicrobial Resistance Collaborators identified that antimicrobial resistance was directly responsible for up to 1.27 million deaths worldwide and was associated with up to 4.95 million deaths, with low-income and middle-income countries being the most severely affected. In 2019, before the COVID-19 pandemic began, they predicted that antimicrobial resistance could result in 10 million deaths per year by 2050, overtaking cancer as a leading cause of death worldwide. Therefore, there is an urgent need for new approaches to antimicrobial treatment. In June 2024, the findings from researchers at the Ineos Oxford Institute for Antimicrobial Research (IOI) and the Oxford University Department of Pharmacology in the UK reported the use of a small molecule that can work alongside antibiotics to suppress the development of antimicrobial resistance in bacteria. The SOS inhibitor molecule has been called OXF-077. This editorial aims to highlight the global threats from increasing antimicrobial resistance and the urgent need for new molecules that function through novel mechanisms of action, including molecular antimicrobial adjuvants.

The interactive effects of medicinal dyes with conventional antimicrobials against skin pathogens.

AIMS: This study aimed to explore potential synergistic effects of medicinal dyes with antimicrobials against pathogens responsible for skin infections. METHODS AND RESULTS: Antimicrobial testing was conducted using minimum inhibitory concentrations and minimum bactericidal/fungicidal concentration assays. The fractional inhibitory index (ΣFIC) of combinations was calculated, and isobolograms were constructed on selected combinations. Toxicity studies were conducted using the brine-shrimp lethality assay. Combination (1:1 ratio) studies noted that 26% of dye-antibiotic combinations were synergistic against the Gram-positive strains, 15% against the Gram-negative strains, and 14% against the yeasts. The Mercurochrome: Betadine® combination noted synergy at ratios against all the Staphylococcus aureus strains with ΣFIC values ranging from 0.05 to 0.48. The combination of Gentian violet with Gentamycin noted a 15-fold decrease in toxicity, and a selectivity index of 977.50 against the Escherichia coli (DSM 22314) strain. Time-kill studies were conducted on the combinations with the highest safe selectivity index (SI) value and lowest safe SI value i.e. Gentian violet with Gentamycin and Malachite green with Neomycin. Both combinations demonstrated better antimicrobial activity in comparison to the independent values and the controls. CONCLUSION: This study highlights the potential for medicinal dye combinations as a treatment for skin infections.

Investigating Photoactive Antimicrobials as Alternatives (or Adjuncts) to Traditional Therapy.

Photodynamic therapy (PDT) is an established therapy used for the treatment of cutaneous skin cancers and other non-infective ailments. There has been recent interest in the opportunity to use aPDT (antimicrobial PDT) to treat skin and soft tissue infections. PDT utilizes photosensitizers that infiltrate all cells and "sensitize" them to a given wavelength of light. The photosensitizer is simply highly absorbent to a given wavelength of light and when excited will produce, in the presence of oxygen, damaging oxygen radicals and singlet oxygen. Bacterial cells are comparatively poor at combatting oxidative stress when compared with human cells therefore a degree of selective toxicity can be achieved with aPDT.In this chapter, we outline methodologies for testing aPDT in vitro using standard lab equipment.

Investigating Combination Therapy as a Means to Enhance Activity and Repurpose Antimicrobials.

Current clinical practice assumes that a single antibiotic given as a bolus or as a course will successfully treat most infections. In modern medicine, this is becoming less and less true with drug-resistant, multi-drug-resistant, extensively drug-resistant, and untreatable infections becoming more common. Where single-drug therapy (monotherapy) fails, we will turn to multi-drug therapy. Alternatively, combination therapy could be useful to prevent the emergence of resistance. Multi-drug therapy is already standard for some multi-drug resistant infections and is the standard for the treatment of some pathogens such as Mycobacterium tuberculosis.The use of combination therapy for everyday infections could be a clear course out of the current AMR crisis we are facing. With every additional drug added to a combination (n + 1) the likelihood of the pathogen evolving resistance drops exponentially.Many generic antibiotics are cheap to manufacture as they have fallen out of patent protection but are less effective at pharmacologically effective doses due to overuse in the past. Combination therapy can combine these generic compounds into cocktails that can not only treat susceptible and resistant infections but can also reduce the risk of new resistances arising and can resuscitate the use of antimicrobials once thought defunct.In this chapter, we will summarize theory behind combination therapy and standard in vitro methodologies used.

Antimicrobial use practices in canine and feline patients with co-morbidities undergoing dental procedures in primary care practices in the US.

This study aimed to investigate how the presence of co-morbid conditions influenced antimicrobial usage as presumptive prophylaxis for suspected bacteremia in dogs and cats undergoing dental treatments at primary care veterinary clinics in the United States. In 2020, data was collected from 1076 veterinary clinics across 44 US states. A total of 681,541 general anesthesia dental procedures were conducted on 592,472 dogs and 89,069 cats. This revealed that systemic antimicrobials were administered in 8.8% of dog procedures and 7.8% of cat procedures in the absence of concurrent periodontal disease or extractions. Cefpodoxime, clindamycin, and amoxicillin-clavulanate were the most frequently used antimicrobials in dogs, while cefovecin, amoxicillin-clavulanate, and clindamycin topped the list for cats. Dogs with cardiovascular, hepato-renal, and endocrine co-morbidities, as well as those undergoing concurrent removal of cutaneous or subcutaneous neoplasia, displayed higher antimicrobial use. Similarly, cats with endocrine or hepato-renal disease, retroviral infection (i.e., feline leukemia virus (FeLV), feline immunodeficiency virus (FIV)), and concurrent removal of cutaneous or subcutaneous neoplasia exhibited increased antimicrobial use. Dogs with hepato-renal abnormalities had longer treatment durations compared to those without (10.1 vs. 9.6 days). Conversely, cats with concurrent removal of cutaneous or subcutaneous neoplasia had shorter durations of treatment as compared to those that did not have this procedure performed (8.4 vs 9.2 days). The findings of this study underscore the necessity for further research and collaboration within the veterinary community to develop evidence-based guidelines, promoting responsible antimicrobial use, and advancing the field of veterinary dentistry for enhanced patient outcomes.

Mapping a sustainable approach: biosynthesis of lactobacilli-silver nanocomposites using whey-based medium for antimicrobial and bioactivity applications.

This study explores a sustainable approach for synthesizing silver nanocomposites (AgNCs) with enhanced antimicrobial and bioactivity using safe Lactobacillus strains and a whey-based medium (WBM). WBM effectively supported the growth of Lactobacillus delbrueckii and Lactobacillus acidophilus, triggering a stress response that led to AgNCs formation. The synthesized AgNCs were characterized using advanced spectroscopic and imaging techniques such as UV‒visible, Fourier transform infrared (FT-IR) spectroscopy, transmission electron (TEM), and scanning electron microscopy with energy dispersive X-ray analysis (SEM-Edx). Lb acidophilus-synthesized AgNCs in WBM (had DLS size average 817.2-974.3 ± PDI = 0.441 nm with an average of metal core size 13.32 ± 3.55 nm) exhibited significant antimicrobial activity against a broad spectrum of pathogens, including bacteria such as Escherichia coli (16.47 ± 2.19 nm), Bacillus cereus (15.31 ± 0.43 nm), Clostridium perfringens (25.95 ± 0.03 mm), Enterococcus faecalis (32.34 ± 0.07 mm), Listeria monocytogenes (23.33 ± 0.05 mm), methicillin-resistant Staphylococcus aureus (MRSA) (13.20 ± 1.76 mm), and filamentous fungi such as Aspergillus brasiliensis (33.46 ± 0.01 mm). In addition, Lb acidophilus-synthesized AgNCs in WBM exhibit remarkable free radical scavenging abilities, suggesting their potential as bioavailable antioxidants. These findings highlight the dual functionality of these biogenic AgNCs, making them promising candidates for applications in both medicine and nutrition.

In vitro and in silico evaluation of bioactivities and chemical composition of the aerial parts of Anchusa officinalis L. methanol extract.

The main objective of the study is to evaluate the antioxidant, anticancer, and antimicrobial activities of Anchusa officinalis L. in vitro and in silico. The dried aerial parts of A. officinalis L. were extracted with methanol. Total phenolic and flavonoid content was analyzed. Antioxidant and antimicrobial effects were tested against both gram-positive and gram-negative bacteria. Gas chromatography-mass spectrometry analysis revealed the presence of 10 phytochemical compounds, and cyclobutane (26.07%) was identified as the major photochemical compound. The methanol extract exhibited the maximum amount of total phenolic content (118.24 ± 4.42 mg QE/g dry weight of the dry extract) (R2 = 0.994) and the total flavonoid content was 94 ± 2.34 mg QE/g dry weight of the dry extract (R2 = 0.999). The IC50 value for 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid was 107.12 ± 3.42 µg/mL, and it was high for 1,1-diphenyl-2-picryl hydrazyl (123.94 ± 2.31 µg/mL). The IC50 value was 72.49 ± 3.14 against HepG2 cell lines, and a decreased value was obtained (102.54 ± 4.17 g/mL) against MCF-7 cell lines. The methanol extract increased the expression of caspase mRNA and Bax mRNA levels when compared to the control experiment (p < .05). The conclusions, A. officinalis L. aerial parts extract exhibited antibacterial, antifungal, and antioxidant activities.

Unlocking the therapeutic potential of Nigella sativa extract: phytochemical analysis and revealing antimicrobial and antioxidant marvels.

The growing global threat of antimicrobial resistance endangers both human and animal life, necessitating the urgent discovery of novel antimicrobial solutions. Medicinal plants hold promise as sources of potential antimicrobial compounds. In this study, we investigated the phytochemical constituents and microbicidal capabilities of the ethanolic extract from Nigella sativa (black seed). Gas chromatography analysis (GC) identified 11 compounds, among them thymoquinone, and thymol, contributing to antimicrobial and antioxidant properties. Antimicrobial assays demonstrated notable inhibition zones against broad spectra of bacteria, including Pseudomonas aeruginosa, Escherichia coli, Salmonella typhi, Staphylococcus aureus, Enterobacter, and Bacillus subtilis, along with potent antifungal activity against Aspergillus niger, Penicillium, and Candida albicans. Notably, when combined with antibiotics, the extract displayed exceptional synergistic antimicrobial efficacy. The black seed extract demonstrated membrane-damaging activity and disrupted virulence factors that protect microbes from antimicrobial agents, including the formation of bacterial biofilm and protease secretion. Thymoquinone, the primary active constituent of the extract, exhibited similar antimicrobial and ant virulence properties. In silico analysis targeting key regulators of quorum sensing and biofilm formation in P. aeruginosa, such as RhlG, LasR, and PqsR, showed a remarkable affinity of thymol and thymoquinone for these targets. Moreover, the N. sativa extract exhibited dose-dependent cytotoxicity against both the promastigote and amastigote forms of Leishmania tropica parasites, hinting at potential antiparasitic activity. In addition to its antimicrobial properties, the extract displayed potential antioxidant activity at a concentration of 400 µg/mL.

The Antimicrobial Activity of Human Defensins at Physiological Non-Permeabilizing Concentrations Is Caused by the Inhibition of the Plasma Membrane H+-ATPases.

Human defensins are cysteine-rich peptides (Cys-rich peptides) of the innate immune system. Defensins contain an ancestral structural motif (i.e., γ-core motif) associated with the antimicrobial activity of natural Cys-rich peptides. In this study, low concentrations of human α- and ß-defensins showed microbicidal activity that was not associated with cell membrane permeabilization. The cell death pathway was similar to that previously described for human lactoferrin, also an immunoprotein containing a γ-core motif. The common features were (1) cell death not related to plasma membrane (PM) disruption, (2) the inhibition of microbicidal activity via extracellular potassium, (3) the influence of cellular respiration on microbicidal activity, and (4) the influence of intracellular pH on bactericidal activity. In addition, in yeast, we also observed (1) partial K+-efflux mediated via Tok1p K+-channels, (2) the essential role of mitochondrial ATP synthase in cell death, (3) the increment of intracellular ATP, (4) plasma membrane depolarization, and (5) the inhibition of external acidification mediated via PM Pma1p H+-ATPase. Similar features were also observed with BM2, an antifungal peptide that inhibits Pma1p H+-ATPase, showing that the above coincident characteristics were a consequence of PM H+-ATPase inhibition. These findings suggest, for the first time, that human defensins inhibit PM H+-ATPases at physiological concentrations, and that the subsequent cytosolic acidification is responsible for the in vitro microbicidal activity. This mechanism of action is shared with human lactoferrin and probably other antimicrobial peptides containing γ-core motifs.

Antimicrobial Activity of Positively Charged Oligopeptides with Theoretical High α-Helix Content against Cutibacterium acnes.

Cutibacterium acnes is abundant and commonly exists as a superficial bacteria on human skin. Recently, the resistance of C. acnes to antimicrobial agents has become a serious concern, necessitating the development of alternative pharmaceutical products with antimicrobial activity against C. acnes. To address this need, we evaluated the antimicrobial activity of CKR-13-a mutant oligopeptide of FK-13 with increased net charge and theoretical α-helical content-against C. acnes in modified Gifu Anaerobic Medium broth by determining the minimum inhibitory concentration (MIC). CKR-13 exerted greater antimicrobial activity against C. acnes than FK-13 in the broth at pH 7.0. The antimicrobial activity of CKR-13 with RXM against C. albicans was pH-dependent. The ionization of CKR-13 and pH-dependent growth delay of C. albicans was suggested to be associated with the increase in CKR-13 antimicrobial activity.