Effective Antimicrobial Activity Research Articles

Polydopamine contained hydrogel nanocomposites with combined antimicrobial and antioxidant properties for accelerated wound healing

Overproduction of reactive oxygen species (ROS) in infected wounds induces a tremendous inflammatory reaction to delay wound healing. To address this problem, we designed a multifunctional polyacrylamide/PVA-based hydrogel containing synthesized poly(1-glycidyl-3-butylimidazolium salicylate) (polyGBImSal) and fabricated polydopamine-coated polyphenolic nanosheet (PDA@PNS) for wound dressing. The PDA@PNS particles were designed to induce I) antioxidant and anti-inflammatory features through ROS-scavenging and II) cell adhesive properties by the existing polydopamine into the hydrogels. The poly(ionic liquid)-based polyGBImSal was designed to allocate effective hydrogel antimicrobial activity. The fabricated hydrogel nanocomposites showed excellent properties in the swelling ratio, cell adhesiveness, protein adsorption, and anti-inflammatory, proving their general performance for application in wound healing. Furthermore, these hydrogels showed high antimicrobial activity (over 95 %) against three common wound-infecting pathogenic microbes: Escherichia coli, Staphylococcus aureus, and Candida albicans. The healing process of full-thickness dermal wounds in rats was accelerated by applying hydrogel nanocomposites with 0.5 wt% of PDA@PNS and 28 wt% of polyGBImSal. The wound closure contraction attained full closure, reaching 100 %, after 14 days, contrasted with the control group employing commercial wound dressing (Tegaderm), which achieved a closure rate of 68 % within the equivalent timeframe. These results make these hydrogel nanocomposites promising candidates for multifunctional wound dressing applications.

Antimicrobial efficacy of Punica granatum Lythraceae peel extract against pathogens belonging to the ESKAPE group.

The improper use and abuse of antibiotics have led to an increase in multidrug-resistant (MDR) bacteria resulting in a failure of standard antibiotic therapies. To date, this phenomenon represents a leading public health threat of the 21st century which requires alternative strategies to fight infections such as the identification of new molecules active against MDR strains. In the last 20 years, natural extracts with biological activities attracted scientific interest. Following the One Health Approach, natural by-products represent a sustainable and promising alternative solution. Consistently, the aim of the present study was to evaluate the antimicrobial activity of hydro-alcoholic pomegranate peel extract (PPE) against MDR microorganisms belonging to Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp. "ESKAPE" group pathogens. Through semiquantitative and quantitative methods, the PPE showed effective antimicrobial activity against Gram-positive and Gram-negative MDR bacteria. The kinetics of bactericidal action of PPE highlighted that microbial death was achieved in a time- and dose-dependent manner. High concentrations of PPE exhibited antioxidant activity, providing a protective effect on cellular systems and red blood cell membranes. Finally, we report, for the first time, a significant intracellular antibacterial property of PPE as highlighted by its bactericidal action against the staphylococcal reference strain and its bacteriostatic effect against clinical resistant strain in the HeLa cell line. In conclusion, due to its characterized content of polyphenolic compounds and antioxidant activity strength, the PPE could be considered as a therapeutic agent alone or in conjunction with standard antibiotics against challenging infections caused by ESKAPE pathogens.

Dual antibacterial/antiviral performance of ZIFs for highly contaminated sanitary surfaces

Effective antimicrobial activity on highly contaminated surfaces, like in sanitary, requires the development of novel functional nanomaterials. In this work, we synthesized zeolitic imidazolate frameworks (ZIFs, 7 and 8) and validated their dual antibacterial/antiviral activity for real applications in sanitary. ZIF-7 and ZIF-8 presented the polygonal morphology associated with the organic ligand arrangement with a crystalline sodalite conformation, and significant surface area (SA) differences were found (38 vs. 1456 m2/g) and associated with particle agglomeration in ZIF-7. The in-vitro antibacterial performance indicated that the high SA of ZIF-8 enabled activity at early and late interaction stages promoted by the controlled Zn ion release in solution. Similarly, ZIF-8 induces the HSV1 virus inactivation during the host infection, demonstrating a high antiviral performance (ca. 96 %). This was also validated when depositing onto flush buttons and door handles in a sanitary.

Optimizing Wound Healing: Examining the Influence of Biopolymers Through a Comprehensive Review of Nanohydrogel-Embedded Nanoparticles in Advancing Regenerative Medicine.

Nanohydrogel wound healing refers to the use of nanotechnology-based hydrogel materials to promote the healing of wounds. Hydrogel dressings are made up of a three-dimensional network of hydrophilic polymers that can absorb and retain large amounts of water or other fluids. Nanohydrogels take this concept further by incorporating nanoscale particles or structures into the hydrogel matrix. These nanoparticles can be made of various materials, such as silver, zinc oxide, or nanoparticles derived from natural substances like chitosan. The inclusion of nanoparticles can provide additional properties and benefits to the hydrogel dressings. Nanohydrogels can be designed to release bioactive substances, such as growth factors or drugs, in a controlled manner. This allows for targeted delivery of therapeutics to the wound site, promoting healing and reducing inflammation. Nanoparticles can reinforce the structure of hydrogels, improving their mechanical strength and stability. Nanohydrogels often incorporate antimicrobial nanoparticles, such as silver or zinc oxide. These nanoparticles have shown effective antimicrobial activity against a wide range of bacteria, fungi, and other pathogens. By incorporating them into hydrogel dressings, nanohydrogels can help prevent or reduce the risk of infection in wounds. Nanohydrogels can be designed to encapsulate and release bioactive substances, such as growth factors, peptides, or drugs, in a controlled and sustained manner. This targeted delivery of therapeutic agents promotes wound healing by facilitating cell proliferation, reducing inflammation, and supporting tissue regeneration. The unique properties of nanohydrogels, including their ability to maintain a moist environment and deliver bioactive agents, can help accelerate the wound healing process. By creating an optimal environment for cell growth and tissue repair, nanohydrogels can promote faster and more efficient healing of wounds.

Mitigation Potential of Herbal Extracts and Constituent Bioactive Compounds on Salmonella in Meat-Type Poultry.

Herbal extracts have been widely evaluated in poultry production for their beneficial effects and potential substitute for antibiotics, which contribute to AMR and risks to human health through the consumption of infected meat. Salmonellosis is a systemic infection caused by Salmonella, an intracellular bacterium with the ability to cause systemic infections with significant implications for both the health and safety of farmers and consumers. The excessive use of antibiotics has escalated the incidence of antibiotic resistance bacteria in the poultry and livestock industry, highlighting the urgent need for alternatives especially in meat-type poultry. Both in vivo usage and in vitro studies of bioactive compounds from herbal extracts have demonstrated the effective antimicrobial activities against pathogenic bacteria, showing promise in managing Salmonella infections and enhancing poultry performance. Phytobiotic feed additives have shown promising results in improving poultry output due to their pharmacological properties, such as stimulating consumption, and enhancing antioxidant properties and preventing the increasing antimicrobial resistance threats. Despite potential for synergistic effects from plant-derived compounds, a further investigation into is essential to fully understand their role and mechanisms of action, for developing effective delivery systems, and for assessing environmental sustainability in controlling Salmonella in poultry production.

Evaluation of the antimicrobial and antioxidant properties of synthetic phenolipids

Functionalization of phenolic compounds by lipophilization allowing the synthesis of new compounds with improved biological properties. This study aims to investigate the antimicrobial effects of eight synthesized phenolipids, derived from bioactive coumaric and ferulic acid esters, against Bacillus subtilis, Escherichia coli, and Candida albicans. Antioxidant activity, as well as antimicrobial capacity were evaluated through DPPH assays and classical disc agar diffusion, respectively, concomitantly with the evaluation of cellular viability using flow cytometry assay. Antioxidant activities results showed that ferulic acid esters exhibit higher antiradical activity than coumaric acid esters. Results of agar diffusion assay revealed that, 1-methylpropyl coumarate and 1-methylpropyl ferulate (1-MPF) have an effective antimicrobial activity with Minimum Inhibitory Concentrations (MICs) values between 0.9 – 3.5mM against all tested microorganisms. Also, flow cytometry showed that 1-MPF and decyl coumarate exhibited significant bactericidal activity (p < 0.05), with almost 63% of dead Bacillus subtilis cells. Compared to the commonly used agar method, flow cytometry proved to be a fast and straightforward analytical tool to assess antimicrobial activity while providing information on inhibition type. These results suggest the applicability of phenolipids as potent lipophilic bioactive molecules to protect food products and cosmetic formulations from oxidative stress and microbial spoilage.

Exogenous non-coding dsDNA-dependent trans-activation of phagocytes augments anti-tumor immunity

Stimulator of interferon genes (STING)-dependent signaling is requisite for effective anti-microbial and anti-tumor activity. STING signaling is commonly defective in cancer cells, which enables tumor cells to evade the immunosurveillance system. We evaluate here whether intrinsic STING signaling in such tumor cells could be reconstituted by creating recombinant herpes simplex viruses (rHSVs) that express components of the STING signaling pathway. We observe that rHSVs expressing STING and/or cGAS replicate inefficiently yet retain invivo anti-tumor activity, independent of oncolytic activity requisite on the trans-activation of extrinsic STING signaling in phagocytes by engulfed microbial dsDNA species. Accordingly, the invivo effects of virotherapy could be simulated by nanoparticles incorporating non-coding dsDNA species, which comparably elicit the trans-activation of phagocytes and augment the efficacy of established cancer treatments including checkpoint inhibition and radiation therapy. Our results help elucidate mechanisms of virotherapeutic anti-tumor activity as well as provide alternate strategies to treat cancer.

Sapindus Mukurossi – An Effective Biocleanser for Removable Dental Prostheses? An In vitro Study

ABSTRACT This study aims to determine the efficient concentration of Sapindus mukorossi that can be used as a denture cleanser. 60 heat cure denture base resin specimens of dimensions 10*10*2 mm were fabricated. Among these, 30 were fabricated by compression moulding technique and the remaining 30 by an injection moulding technique. The samples inoculated with Candida albicans and Streptococcus mutans were subjected to denture cleansing protocols using a medicinal herbal extract from the Sapindus mukorossi, at various concentrations [15%, 20%, and 25%]. The colony-forming unit [CFU] values were evaluated using a microprocessor colony counter. The statistical analysis was performed. The intragroup comparison showed a statistically significant difference between all groups except the compression moulded samples inoculated with Streptococcus mutans. The intergroup comparison revealed no statistically significant differences between the compared groups. The reduction in CFU values is evident in the effective anti-microbial activity of Sapindus mukorossi. A concentration of 25% Sapindus mukorossi solution showed the greatest efficiency. The maximum anti-microbial activity was observed against Candida albicans in a 25% concentration of Sapindus mukorossi. Among all, injection moulded samples showed better results.

Effect of the Incorporation of Compounds into Digitally Manufactured Dental Materials—A Systematic Review

The aim of this review was to evaluate if the properties of digitally produced dental acrylic resins improved when reinforced with compounds. A literature search was conducted in PubMed, Web of Science, and Scopus databases for the past 10 years. Combinations of keywords were chosen to reflect the PICO question: Do digitally produced dental acrylic resins loaded with compounds have better mechanical, surface and/or biological properties than resins without compounds? The selection was carried out by two independent researchers according to the PRISMA flowchart and specific eligibility criteria. Results: The 19 in vitro studies included dealt with incorporated compounds such as zirconium dioxide nanoparticles, graphene nanoplatelets, and zwitterionic compounds. It was found that some compounds had a negative impact on the mechanical and surface properties, while others showed improvements. Most of the loaded resins had more effective antimicrobial activity compared to the controls. There were also differences in biocompatibility depending on the type of compound incorporated. The compounds affect the mechanical and surface properties of loaded acrylic resins, depending on the type and concentration of the compound. In the case of antimicrobial activity and biocompatibility, the results depended on other factors than the chemical composition of the compound included in the resin.

Central Nervous System Antimicrobial Exposure and Proposed Dosing for Anthrax Meningitis.

The high mortality of systemic anthrax is likely a consequence of the severe central nervous system (CNS) inflammation that occurs in anthrax meningitis. Effective treatment of such infections requires, at a minimum, adequate cerebrospinal fluid (CSF) antimicrobial concentrations. We reviewed English medical literature and regulatory documents to extract information on serum and CSF exposures for antimicrobials with in vitro activity against Bacillus anthracis. Using CSF pharmacokinetic exposures and in vitro B. anthracis susceptibility data, we employed population pharmacokinetic modeling and Monte Carlo simulations to predict whether a specific antimicrobial dosage would likely achieve effective CSF antimicrobial activity in patients with normal to inflamed meninges (i.e., an intact to markedly disrupted blood brain barrier). Probability of microbiologic success at achievable antimicrobial dosages was high (≥95%) for ciprofloxacin, levofloxacin (500 mg q12 h), meropenem, imipenem/cilastatin, penicillin G, ampicillin, ampicillin/sulbactam, doxycycline, and minocycline; acceptable (90-95%) for piperacillin/tazobactam and levofloxacin (750 mg q24 h); and low (<90%) for vancomycin, amikacin, clindamycin, and linezolid. Prompt empiric antimicrobial therapy of patients with suspected or confirmed anthrax meningitis may reduce the high morbidity and mortality. Our data support using several β-lactam-, fluoroquinolone-, and tetracycline-class antimicrobials as first-line and alternative agents for treatment of patients with anthrax meningitis; all should achieve effective microbiologic exposures. Our data also suggest antimicrobials that should not be relied upon to treat suspected or documented anthrax meningitis. Furthermore, the protein synthesis inhibitors clindamycin and linezolid can decrease toxin production and may be useful components of combination therapy.

Zein and tannic acid hybrid particles improving physical stability, controlled release properties, and antimicrobial activity of cinnamon essential oil loaded Pickering emulsions

Pickering emulsion loading essential oil has demonstrated a promising strategy as delivery system in food preservation, but localization in stability and antimicrobial activity limits application. In this study, Pickering emulsions co-loaded with tannic acid and cinnamon essential oil (ZTC) have been developed based on zein and tannic acid complexes (ZT) mediated interfacial engineering. Fourier transform infrared, fluorescence spectroscopy, and molecular docking results indicated tannic acid altered the structural of zein. Interfacial tension results indicated that tannic acid accelerated the adsorbed speed of zein particles by decreased interfacial tension (11.99–9.96 mN/m). ZT5 formed a viscoelastic and dense layer in oil–water interface than that for other ZTs, which improved stability and control release performance of ZTC. Furthermore, the ZTC showed an effective antimicrobial activity against spoilage organisms Pseudomonad paralactis MN10 and Lactobacillus sakei VMR17. These findings provide new insight for developing co-loaded multiple antimicrobial agents within Pickering emulsion as a delivery system.

Design, biological characteristics, and antibacterial mechanism of high therapeutic index antimicrobial peptides with PRRP as central axis.

As the important components of biological innate immunity, antimicrobial peptides (AMPs) were found in a variety of organisms including insects, plants, animals, bacteria, fungi, etc. However, high hemolytic activity, high toxicity, and poor stability of natural AMPs hinder serious their application as therapeutic agents. To overcome these problems, in this study we use PRRP as a central axis, and peptides were designed based on the sequence template XRRXXRXPRRPXRXXRRX-NH2, where X represents a hydrophobic amino acid like Phe (F), Ile (I), Val (V), and Leu (L). The designed peptides LR18, FR18, and IR18 showed effective antimicrobial activity against some Gram-positive bacteria and Gram-negative bacteria, low cytotoxicity to mammalian cells, and had a tendency to form α-helical structures in membrane-mimetic environments. Among them, peptide LR18 (X: L) showed the highest geometric mean average treatment index (GMTI = 42.7) against Gram-negative bacteria, and FR18 (X: L) showed the highest GMTI (22.86) against Gram-positive bacteria. LR18 and FR18 also showed better salt, temperature, pH, and trypsin stability. LR18 and FR18 exert their antimicrobial effects mainly through destroying bacteria cell membrane. Briefly, peptide LR18 and FR18 have the potential to serve as a therapeutic agent to reduce antibiotic resistance owing to its high therapeutic index and great stability.

Synthesis of 5-heptadecyl-4H-1,2,4-triazole incorporated indole moiety: Antiviral (SARS-CoV-2), antimicrobial, and molecular docking studies

Two series of Schiff bases and Mannich bases derived from 5-heptadecyl-4H-1,2,4-triazole hybrids of indole moiety have been synthesized. First, the acid-catalyzed reaction of N-substituted-1H-indole-3-carboxaldehydes with the modified fatty acid, 4-amino-5-heptadecyl-4H-1,2,4-triazole-3-thiol, afforded 1,2,4-triazole Schiff bases 5a-d. Treatment of 5a-d with some halo-compounds gave S-alkyl-1,2,4-triazoles 6a-d to 9a-d. Additionally, the reaction of 5a-d with different secondary amine and paraformaldehyde afforded Mannich base products 10a-d to 13a-d. Basically, viral infections are often followed by bacterial infections that require antimicrobial treatment. The antiviral bioassay revealed that compounds 6d and 7d exhibited significant antiviral activity against NRC-03-nhCoV with IC50 equal 8.7 and 8.925 μM, respectively. Next, the synthesized compounds were evaluated for their antimicrobial activity against Gram-positive and Gram-negative bacteria as well as yeast and fungi. Compound 5b exhibited effective antimicrobial activities against all microbial test strains. 5b revealed MIC values of 19.53 μg/mL against S. aureus, 39.063 μg/mL against E. coli, and 39.125 μg/mL against C. albicans. On top of that, the release of reducing sugars and proteins from the treated bacterial strains over the untreated bacterial strains was undertaken to describe the effect of compound 5b on the intact cells. Furthermore, scanning electron microscopy (SEM) has been applied to study the possible sterilization process of the antimicrobial compound 5b. The results indicated the possibility of destroying the cell membrane structure of microbes, resulting in incomplete microbial structures, and thus achieving inhibition. To putatively highlight the antiviral and antimicrobial activities of the potent compounds, they were subjected to molecular docking against the key viral and microbial protein targets.

Novel amide based macrocyclic complexes of Co(II): Synthesis, structural characterization, thermal, DFT, molecular docking studies, in vitro cytotoxic, antimicrobial and antioxidant evaluation

The novel cobalt (II) macrocyclic complexes [Co(N4O4MacL1)Cl2]-[Co(N4O4MacL3)Cl2] have been synthesized by using the macrocyclic ligands [N4O4MacL1], [N4O4MacL2] and [N4O4MacL3] that have an N4O4 core. To investigate Co(II), metal complexes [Co(N4O4MacL1)Cl2]-[Co(N4O4MacL3)Cl2] with new ligands, elemental analyses, infrared, magnetic measurements, UV–visible, 1H NMR, 13C NMR, and XRD studies were utilised. According to the spectrum data, the ligands perform as a mononegative tetradentate. Based on magnetic and electronic spectrum data, an octahedral structure for Co(II) metal complexes has been postulated. The Coats-Redfern and FWO techniques are used to determine the thermodynamic characteristics of ligands and their complexes. The molecular modelling using the DFT technique displays bond angles, bond lengths, and quantum chemical factors. To determine their ability to prevent the growth of harmful fungus and bacteria, the ligands [N4O4MacL1]- [N4O4MacL3] and their complexes were tested in vitro against A. Niger, C. albicans and B. subtilis, S. aureus, E. coli and S. typhi fungal and bacterial organisms, respectively. By using DPPH free radical scavenger assays, the in vitro antioxidant capabilities of each compound were evaluated. The [Co(N4O4MacL3)Cl2] antioxidative capabilities revealed significant radical scavenging power. All of the compounds under research were examined for cytotoxicity using the MTT assay on MCF-7 and HepG-2 cells, and the findings revealed that [Co(N4O4MacL2)Cl2] show outstanding cytotoxic activity against HepG-2 with IC50 17.94 ± 045 at a concentration of 25 ppm. Additionally, docking investigations of the produced compounds were carried out in order to validate the biological outcomes. Considerably, the current Co (II) complexes with their effective antimicrobial, antioxidant, and cytotoxicity activity would be probably appraised for further medicinal and pharmaceutical applications.

Drug repurposing: insights into the antimicrobial effects of AKBA against MRSA

Staphylococcus aureus is a major threat in infectious diseases due to its varied infection types and increased resistance. S. aureus could form persister cells under certain condition and could also attach on medical apparatus to form biofilms, which exhibited extremely high resistance to antibiotics. 3-Acetyl-11-keto-beta-boswellic acid (AKBA) is a well-studied anti-tumor and antioxidant drug. This study is aimed to determine the antimicrobial effects of AKBA against S. aureus and its persister cells and biofilms. The in vitro antimicrobial susceptibility of AKBA was assessed by micro-dilution assay, disc diffusion assay and time-killing assay. Drug combination between AKBA and conventional antibiotics was detected by checkerboard assay. And the antibiofilm effects of AKBA against S. aureus were explored by crystal violet staining combined with SYTO/PI probes staining. Next, RBC lysis activity and CCK-8 kit were used to determine the cytotoxicity of AKBA. In addition, murine subcutaneous abscess model was used to assess the antimicrobial effects of AKBA in vivo. Our results revealed that AKBA was found to show effective antimicrobial activity against methicillin-resistant S. aureus (MRSA) with the minimal inhibitory concentration of 4–8 µg/mL with undetectable cytotoxicity. And no resistant mutation was induced by AKBA after 20 days of consecutive passage. Further, we found that AKBA could be synergy with gentamycin or amikacin against S. aureus and its clinical isolates. By crystal violet and SYTO9/PI staining, AKBA exhibited strong biofilm inhibitory and eradication effects at the concentration of 1 ~ 4 µg/mL. In addition, the effective antimicrobial effect was verified in vivo in a mouse model. And no detectable in vivo toxicity was found. These results indicated that AKBA has great potential to development as an alternative treatment for the refractory S. aureus infections.

Enzyme-triggered on-demand release of a H2O2-self-supplying CuO2@Fe3O4 nanoagent for enhanced chemodyamic antimicrobial therapy and wound healing.

Nanoagents for chemodynamic therapy (CDT) hold a promising future in the field of antimicrobials, especially copper peroxide (CuO2) (CP) nanomaterials which have garnered significant attention due to their ability to self-supply H2O2. Nevertheless, the poor stability of CuO2 remains a critical challenge which restricts its practical application in the antibacterial field. In this study, an advanced nano-antimicrobial system HA-CP@Fe3O4 with enzyme-responsive properties is developed by coating hyaluronic acid (HA) on CuO2-loaded iron tetraoxide nanoparticles. The coating of HA not only stabilizes the CuO2 nanomaterials but also provides responsiveness towards the enzyme hyaluronidase, which is typically secreted by some bacteria. The outer layer of HA in HA-CP@Fe3O4 undergoes decomposition in the presence of hyaluronidase-secreting bacteria, resulting in the release of CuO2@Fe3O4. The released CuO2@Fe3O4 then self-supplies H2O2 and generates reactive oxygen species (ROS) within the infected microenvironment through Fenton and Russell effects, to ultimately achieve effective and precise antimicrobial activity. Simultaneously, the magnetic property provided by Fe3O4 allows the substance to be directed towards the infection site. Both in vitro and in vivo tests demonstrated that HA-CP@Fe3O4 exhibited excellent antimicrobial capabilities at low concentration (30 μg mL-1), exceptional biocompatibility and the ability to accelerate wound healing. The findings of this work offer a new and promising approach for targeted and precise CDT.

Use of essentialoils in meatprocessing

Essential oils are natural plant products with rich chemical composition and various properties. They are obtained by extraction from plant parts such as flowers, buds, stems, twigs, seeds, fruits, roots, bark and leaves. They contain over sixty organic compounds with low molecular weight, including: phenolic and terpene compounds, aliphatic alcohols, aldehydes, ketones, acids and isoflavonoids. The composition, concentration and proportions of chemical components in essential oils determine their properties. Essential oils have a significant impact on living organisms, including antiviral, antibacterial, antifungal, antiparasitic, anti-inflammatory and antioxidant properties. Depending on the concentration used, essential oils positively or negatively affect the sensory properties of meat products. It is important to obtain a sensorially acceptable concentration of essential oil in the product, which will also ensure effective antimicrobial activity. By applying several essential oils at the same time or using other preservatives or preservation and packaging methods with them, a synergistic effect can be achieved, thanks to which the concentration of the essential oil in the product can be reduced. Factors that can influence the antimicrobial effect of essential oils in food products include: food structure, composition, pH, storage conditions and the type of saprophytic microbiota in the product. Essential oils can have a positive impact on the microbiological quality of food and can be used in the food industry as a factor inhibiting the growth of saprophytic microorganisms that affect the durability of food and pathogenic bacteria that cause food poisoning.

Mersin, Türkiye'den Bazı Maki Türlerinin Antimikrobiyal ve Antioksidan Aktiviteleri

In this paper, we have investigated antimicrobial and antioxidant activity of some maquis species from Mersin vil., Turkey. Extracts of Cistus creticus L. Erica manipuliflora L., Myrtus communis L., Pistacia terebinthus L. and Rosmarinus officinalis L., species, which are the elements of the scrub vegetation, were obtained by using hexane, methanol and petroleum ether solvents, respectively, and the antioxidant and antimicrobial properties of these extracts were determined. The plant samples showed different antimicrobial and antioxidant activity. Specifically, M. communis extracts has more effective antimicrobial activity against Gram(+) bacteria species. M. communis methanolic extract showed the MIC value of 31.25 µg/mL against S. aureus, S. pneumoniae and E. faecalis. M. communis hexane extract showed that the MIC value of 31.25 µg/mL against E. faecalis. In the current study, the petroleum ether extract of M. communis showed the highest antifungal effect against C. parapsilosis with a MIC value of 31.25 µg/mL. The highest and lowest DPPH radical scavenging activity were calculated as 91.25 % and 63.3 % in the petroleum ether extract of P. terebinthus and in the methanolic extract of C. creticus, respectiley. Furthermore, the highest and lowest hydrogen peroxide (H2O2) scavenging activity were found to be 78.87 % and 45.8 % in the methanolic extract of M. communis and in hexane extract of C. creticus, respectively.

Investigation of the treatment and antibacterial properties of pollutant-containing water using black phosphorus blended polyethersulfone membranes (BP@PES)

The most important problem of membrane processes is clogging and therefore the reduction of their useful life. In order to eliminate such problems, the production of composite membranes is an option in membrane treatment systems. In this study, the usability of black phosphorus (BP) in membrane treatment systems, and its effect on antibacterial and treatment performance were studied. BP blended PES membranes (BP@PES) produced by loading BP into the polyethersulfone (PES) membranes were used for the treatment of bovine serum albumin (BSA) and Escherichia coli (E. coli). For this purpose, BP was added at three different amounts (0.5 %, 1.0 %, and 2.0 %) into PES membranes. Membranes with different BP amounts produced were named as 0.5%BP@PES, 1.0%BP@PES, and 2.0%BP@PES. After the production of these composite membranes, they were used in the dead-end filtration system and compared with the PES membrane without BP (bare PES). The removal effectiveness of bare PES was found to be 53.40 % in the BSA rejection results, and it was discovered to be 60.90 %, 97.15 %, and 100 % for 0.5%BP@PES, 1.0%BP@PES, and 2.0%BP@PES, respectively. The antioxidant activity of BP was 70.86% at 100 mg/L. Newly prepared BP caused single-strand DNA nuclease abilities at 50, 100, and 200 mg/L. BP showed the effective antimicrobial activity. The most antimicrobial activity was determined as a minimum inhibitory concentration (MIC) value of 8 mg/L against E. hirae and 100 % E. coli viability inhibition activity was achieved at 50 and 100 mg/L after 90 min exposure. BP also inhibited the biofilm formation of P. aeruginosa at 87.19 % and S. aureus at 90.28 % at 50 mg/L. Thus, both the effect of BP on membrane performance and its antibacterial properties were investigated. Pure water fluxes, BSA and E.coli rejection performances, and antibacterial properties of all membranes used in the membrane filtration system were investigated in detail. It is recommended to further investigate BP-containing membranes with different production techniques.

Pyrazole Scaffolds Having Promising Pharmacological Potential: A Review.

Heterocyclic compounds have diverse structure, which makes them broad and economical therapeutic agents. Pyrazole is a five-membered aromatic ring that contains two nitrogen atom and is responsible for the diverse functions of heterocyclic compounds. This implies the need of reviewing the work that already has been done on the potential of pyrazole scaffolds in the field of medicinal chemistry for the synthesis of new compounds with more effective antimicrobial, antioxidant, anticancer, anti-tuberculosis, and anti-inflammatory activities.