85,581 results on '"ANTIBACTERIAL agents"'
Search Results
2. Improving Antibiotic Use for ARIs in Urgent Care Clinics
- Author
-
Daniel Livorsi, Associate Professor
- Published
- 2024
3. Comparative analysis of silver titanium alloy and titanium dioxide nanoparticles for antibacterial activity against Pseudomonas aeruginosa as compared with commercial antibiotic Kanamycin.
- Author
-
Saikiran, Madduluru and Paramasivam, Gokul
- Subjects
- *
TITANIUM dioxide nanoparticles , *SILVER alloys , *GRAM-negative bacteria , *PSEUDOMONAS aeruginosa , *ANTIBACTERIAL agents , *TITANIUM alloys - Abstract
The aim of this study is to compare the silver titanium alloy nanoparticles with titanium nanoparticles in a novel antibacterial test against Pseudomonas aeruginosa. Wet chemical methods were used to make silver titanium alloy nanoparticles and titanium nanoparticles. Two groups were studied, each with a sample size of three, for a total sample size of six. Wells' technique was used to test antibacterial activity against P.aeruginosa using silver-titanium alloy nanoparticles and titanium nanoparticles. Antibacterial test analysis reveals that silver titanium alloy nanoparticles concentration (133 µg/100 µl) was found to be statistically significant (p<0.05) compared with titanium nanoparticles. Inhibitory rates of silver titanium alloy nanoparticles were found to be high in antibacterial tests against P.aeruginosa over titanium nanoparticles. In this analysis, silver titanium alloy nanoparticles (AgTiO2) demonstrate viability in antibacterial tests against P.aeruginosa. Silver titanium alloy (Ag-TiO2) nanoparticles were tested against gram negative bacteria (pseudomonas aeruginosa) with better antibacterial activity as compared with TiO2 nanoparticles. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
4. Evaluation of apple rose leaf (Eugenia aqueum) activity on bacteria that cause dental caries.
- Author
-
Suwendar, S. and Wachidah, Lisnur
- Subjects
- *
DISC diffusion tests (Microbiology) , *DENTAL caries , *STREPTOCOCCUS mutans , *ANTIBACTERIAL agents , *TEST methods , *ETHANOL , *ETHYL acetate - Abstract
Dental caries is a health problem in the oral cavity with a high prevalence rate. One of the causes of dental caries is Streptococcus mutans bacteria. Apple rose leaves (Eugena aqueum) have been known to have antibacterial activity. The purpose of this study was to evaluate the activity of apple rose leaves against S. mutans. Evaluation of antibacterial activity was carried out in vitro using the agar diffusion test method by means of wells. The results showed that the ethanol extract and the extract fraction (n-hexane, ethyl acetate and water) of guava leaves had antibacterial activity on S. mutans. Apple rose leaf ethanol extract showed the strongest activity because it had the lowest minimum inhibitory concentration (MIC) compared to the three extract fractions, namely 0.78%, with an average inhibition zone diameter of 1.13 ± 0.02 cm based on three observations. The MIC value of the n-hexane fraction was 3.13% with an average inhibition zone diameter of 1.07 ± 0.02 cm, while the MIC values for ethyl acetate and water fraction were 1.56% each with an average inhibition zone diameter were 1.09 ± 0.03 and 1.08 ± 0.02 cm, respectively. Based on the results of these tests, it can be concluded that apple rose leaves have the potential to be developed into a natural toothpaste preparation that is efficacious in preventing dental caries. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
5. Production, characterization, and antibacterial activity of eco-enzyme from fruit and vegetable wastes.
- Author
-
Patricia, Vinda Maharani, Suarantika, Farendina, Hazar, Siti, Rusdi, Bertha, and Yuniarni, Umi
- Subjects
- *
ESCHERICHIA coli , *ORGANIC wastes , *ANTIBACTERIAL agents , *PRODUCT attributes , *TEST methods , *FOOD aroma - Abstract
Eco-enzyme is a fermented fluid composed of organic waste, sugar, and water that produces a dark brown solution. The fermentation process then lasts three months. Then, following the harvest period, characterization is performed. The process of characterization consists of organoleptic testing and activity testing. In general, this study aims to compare organoleptic tests and their activities from 3 types of sugars used in the eco-enzyme fermentation process. This study showed that the color organoleptic test has significant differences, with the first variable producing a clear brown color and the other variable producing a turbid yellowish-brown color. In aroma testing, all eco-enzyme products produced a characteristic acidic odor at harvest. Eco-enzyme was screened of antibacterial activity against E. coli and S. aureus by dilution with various concentration (1.5625%, 3.125%, 6.25%, 12.5%, 25%, 50%, 100% v/v) and various control. The minimum inhibition concentration (MIC) was then tested by diffusion method to determine the inhibition zone with three replication using the higher concentration (50%, 75%, 100% v/v). The result showed that the MIC of E. coli and S. aureus are 25% and 50%. The dilution test of eco-enzyme gives the most effective concentration to inhibit both bacteria at eco-enzyme 100% (v/v). [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
6. Exploration of potential antioxidant and antibacterial activities of Lampung robusta coffee ethanolic extracts.
- Author
-
Iqbal, Muhammad and Triyandi, Ramadhan
- Subjects
- *
DRUG discovery , *GALLIC acid , *ANTIOXIDANT testing , *ANTIBACTERIAL agents , *DEGENERATION (Pathology) - Abstract
Oxidative damage can cause various degenerative diseases. Degenerative diseases can be exacerbated by deadly infectious diseases. Groups of compounds and natural products that have antioxidant and antibacterial properties can inhibit oxidative damage and infectious diseases. The development of natural products that have the potential as antioxidant and antibacterial agents is a continuous effort in the field of drug discovery. This study aims to explore the potential of Lampung robusta coffee as a nature-based antioxidant and antibacterial agent. Identification of the active compound of the test extract was carried out qualitatively using a reagent solution. Antioxidant potential test using the DPPH method (2,2-Diphenyl-1-Picrylhydrazil). The test samples were made with various levels of 20 g/ml; 40 g/ml, 60 g/ml; 80 g/ml and 100 g/ml. Antibacterial test against several strains (S. aureus; P. aeruginosa) using disc diffusion method. The test extract has antioxidant power with IC50 (Inhibitory Concentration) of 121.45+18.62 g/ml. The total phenolic content of the test extract was 539.03+28.02 mg gallic acid equivalent/g sample. The test extract did not show the diameter zone of inhibition in the antibacterial test. This research can provide scientific evidence of the antioxidant and antibacterial potential of Lampung robusta coffee so that it can become a useful product in society based on science and can be accounted for for its efficacy. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
7. Bioactivity of mangrove derived fungi EtOAc extract as antibacterial agent against Staphylococcus aureus and Pseudomonas aeruginosa.
- Author
-
Juliasih, Ni Luh Gede Ratna, Lutfiah, Rosyidatul, and Setiawan, Andi
- Subjects
- *
SOLID-state fermentation , *MANGROVE forests , *ETHYL acetate , *PATHOGENIC bacteria , *ANTIBACTERIAL agents , *MANGROVE plants - Abstract
Fungi was proven as a source of metabolites which has preferential biological activity. This study aims to screen bioactive compounds fungi derived from mangroves. The isolates of fungi were obtained from Sriminosari mangrove forest, East Sea Coast region, Lampung. Fungi was cultivated and co-cultivate in the solid-state fermentation of rice media. The biomass is then extracted in ethyl acetate. The extract was then tested for the bioactivity potency toward pathogenic bacteria Staphylococcus aureus and Pseudomonas aeruginosa obtained from hospital patients. There are 17 isolates of fungi obtained in this study, consisting of 5 isolate from root, 8 isolate from stem, 1 isolate from leaf, and 3 isolate from mud part. The most common white fungi was obtained in this study. From the disk diffusion method, it is shown that fungi of BA04RF1, BB04RF1, BB05RF1, CB06RF1, CB07RF1, and CD01RF1 are antibacterial agents (100 µg/mL). Furthermore, extracts of CB07RF1 produce the best antibacterial activity toward clinical pathogen S. aureus (14 mm inhibition value) and P. Aeruginosa (12 mm inhibition value). Consequently, some fungi obtained in this study could produce antibacterial compounds, which is crucial as a first step for further research related to fungi in mangrove ecosystems. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
8. Phytochemical screening, GC-MS, FTIR, and antibacterial activity of methanol extract of Caesalpinia Bonduc (L.) roxb. seeds.
- Author
-
Samriani, Samriani, Natsir, Hasnah, Dali, Seniwati, and Arif, Abdur Rahman
- Subjects
- *
PHYTOCHEMICALS , *GAS chromatography/Mass spectrometry (GC-MS) , *METABOLITES , *BIOACTIVE compounds , *GAS analysis , *ANTIBACTERIAL agents , *SAPONINS - Abstract
Caesalpinia bonduc (L.) Roxb. is a medicinal plant belonging to the family Caesalpiniaceae. It's popularly known as gorek in Indonesia. All part of the plant were claimed to possess some therapeutic property, but the seed is the most widely used part in various systems of medicine. The seeds contain secondary metabolites as bioactive compounds therefore this plant has antibacterial activity. This study aimed to identify secondary metabolites and to analysis the Gas Chromatography-Mass Spectrometry (GC-MS) and Fourier Transform Infred (FTIR) of methanol extract of C. bonduc seeds as well as antibacterial activity. The phytochemical screening of methanol extract of C. bonduc seeds indicate the presence of alkaloids, flavonoids, saponins, tannins, and phenolics. The GC-MS analysis showed the presence of 100 different compounds with three main compounds: 4-Methyl-1,3-Dioxolan-2-One, 2-Trimethylsilyl-1,3-dithiane, and Cholesta-5,7,9(11)-trien-3-ol acetate. The FTIR analysis showed that the extract has functional groups O-H, N-H, C-N, C-H, C-O, C=C, C=O, C-S, and C-Si. The antibacterial activity of methanol extract of C. bonduc seeds at various concentrations had an inhibitory activity against the growth of Escherichia coli and Stapylococcus aureus. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
9. Photocatalytic and antibacterial activities of zinc oxide (ZnO) nanoparticles doped with nickel (Ni).
- Author
-
Destalina, Mujtahid, Fitriah, Mutmainnah, Inayatul, and Gareso, Paulus L.
- Subjects
- *
CONGO red (Staining dye) , *PHOTOCATALYSTS , *SODIUM hydroxide , *ANTIBACTERIAL agents , *ESCHERICHIA coli - Abstract
The effect of Nickel (Ni) doping on Zinc Oxide (ZnO) nanoparticles to photocatalytic activity Congo Red (CR) dye has been studied using the coprecipitation method. ZnO(1-x)Ni(x) with various concentrations of x=0 wt %, 5 wt %, 6 wt % and 7 wt % was prepared by sodium hydroxide as a precursor. For the characterization of Ni-doped ZnO nanoparticles, we used FTIR (Fourier transmission infrared) spectroscopy to investigate the functional group of the nanoparticles. The absorption of the samples was recorded in the range of 500 – 4000 cm. The bandgap energy of ZnO nanoparticles decreased with increasing Ni concentration. The photocatalytic experiment reveals that the percentage of degradation of Congo-Red in which the presence of Ni-doped ZnO (Ni 6%) in the solution increased significantly by 98.76% after irradiation at 45 minutes. The increase in the diameter of the inhibition zone along with the increase in the concentration of Ni-doped ZnO nanoparticles with varying concentrations of ZnO0.95Ni0.05, ZnO0.94Ni0.06, ZnO0.93-Ni0.07 with Staphylococcus aureus and Escherichia coli bacteria indicated the presence of significant antibacterial activity of Ni-doped ZnO nanoparticles. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
10. Synthesis, characterization and exploration for biological activities of 3-N-tetra-O-acetyl-β-D glucopyranosyl-5 imino-7-arylimino 1,2,4,6 dithiadiazepine.
- Author
-
Ugale, Manjusha
- Subjects
- *
POTASSIUM carbonate , *CHEMICAL synthesis , *ANTIBACTERIAL agents , *GUANIDINE , *CARBONATES - Abstract
The 3-N-tetra-O-acetyl-β-D glucopyranosyl-5 imino-7-arylimino 1,2,4,6 dithiadiazepine (3) have been prepared by the interaction of amidino thiocarbamides (2) and dichloro derivative of N-tetra-O-acetyl-β-D-glucopyranosyl isothiocyanate. The intermediate amidino thiocarbamide is obtained by refluxing guanidine carbonate, aryl isothiocyanate (1), and potassium carbonate. The targeted compounds have been characterized by analytical and spectral data studies. These synthesized compounds on screening exhibited fairly good antibacterial activity [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
11. Preparation and characterization of carboxymethyl cellulose/polyethylene glycol films containing bromelain/ curcumin: In vitro evaluation of wound healing activity
- Author
-
Mojahedi, Maryam, Kharazi, Anousheh Zargar, and Poorazizi, Elahe
- Subjects
Cellulose ,Bacteria ,Drugs -- Vehicles ,Wound healing ,Dermatology -- Formulae, receipts, prescriptions ,Antibacterial agents ,Skin ,Dermatologic agents ,Polyethylene glycol ,Citric acid ,Drug delivery systems ,Wounds and injuries -- Care and treatment ,Engineering and manufacturing industries ,Science and technology - Abstract
In this study, a wound-healing membrane was fabricated based on carboxymethyl cellulose (CMC) and polyethylene glycol (PEG) containing curcumin (Cur) and bromelain (Br). Citric acid (CA) was used as a cross-linking agent. This membrane showed an ideal degree of swelling, which was significantly dependent on the concentration and duration of cross-linked CA. The chemical characterization showed the CA cross-linker mechanism was more associated with chemical reactions with CMC carboxyl groups, and PEG hydroxyl groups played an important role in forming a hybrid polymer network. It greatly enhanced mechanical and adhesive properties, so the stress strength was improved from 29.4 to 38.52 Mpa. The hydrophilicity of the membrane surface according to the water contact angle assay showed the membrane surface is suitable for adhesion, growth, migration, and proliferation of skin cells. The drug delivery assay demonstrated that the Br and Cur were released during 48 h, but the Br followed the burst release in comparison with Cur. Antibacterial properties showed that CMC/PEG-Cur/Br have ideal antibacterial properties for preventing the growth of bacteria. In summary, the engineered CMC/PEG containing Cur/Br films with desired cell viability properties and antibacterial activity can potentially improve and accelerate skin regeneration for chronic wound healing. Highlights * Hydrogel film was prepared based on carboxymethyl cellulose (CMC), polyethylene glycol (PEG), and citric acid as cross-linking agent. * CMC/PEG film were induced controlling curcumin (Cur) and bromelain (Br) release for wound healing process. * CMC/PEG film revealed a wide range of physiochemical, mechanical, adhesion, and biological properties behavior. * Incorporation of Cur and Br promoted in vitro biocompatibility, L-929 cells attachments, and cell migration. KEYWORDS antibacterial properties, bromelain, carboxymethyl cellulose, curcumin, drug delivery, polyethylene glycol, wound dressing, 1 | INTRODUCTION As the largest human tissue, the skin serves a crucial role as a barrier against infection. (1) Due to an incomplete physical barrier and exposed subcutaneous tissue, [...]
- Published
- 2024
- Full Text
- View/download PDF
12. Electrospun statin-loaded nanofibers for treating diabetic wounds
- Author
-
Pamu, Divya, Garikapati, Kusuma Kumari, Kuppusamy, Gowthamarajan, Krishnamurthy, Praveen Thaggikuppe, Ganesan, Srividhya, Naik, Mudavath Ravi, Karri, Veera Venkata Satyanarayana Reddy, Ponpandian, Nagamony, Alexiou, Athanasios, Antoniou, Sofia, Khan, Azmat Ali, Alanazi, Amer M., and Papadakis, Marios
- Subjects
Streptozocin ,Statins ,Biological products ,Collagen ,Vascular endothelial growth factor ,Antibacterial agents ,Escherichia coli ,Engineering and manufacturing industries ,Science and technology - Abstract
This study aims to develop, characterize, and evaluate the best statin-loaded Collagen Silver nanoparticle-coated polycaprolactone nanofibers by electrospinning technique. The characterization and evaluation results reveal that nanofibers had shown an aligned Collagen Silver nanoparticle-coated polycaprolactone nanofibers distribution of fibers and aliment of collagen and silver nanoparticle coating material on the surface of the nanofibers. Furthermore, the electrospun nanofibers have shown no interaction between the drug and collagen and PCL polymeric material and have demonstrated controlled drug release for 360 h and significant degradation for 60 days of the study. In vitro, among the nanofiber treatment groups and the control groups, Pravastatin Collagen Silver nanoparticle-coated polycaprolactone nanofibers have shown cell proliferation and migration of NHDF cells and blood vessel development in the CAM assay and potential anti-bacterial activity against S. aureus and E. coli. In vivo, the Pravastatin Collagen Silver nanoparticle-coated polycaprolactone nanofibers have demonstrated improved wound recovery, reepithelization, fibroblast cell proliferation, angiogenesis, and ECM remodeling and enhanced VEGF-sprouting in the excised tissues of streptozotocin-induced diabetic rats for 7, 14, and 21 days of the study. Therefore, the developed Pravastatin Collagen Silver nanoparticle-coated polycaprolactone nanofibers could be a promising wound-dressing platform for effectively treating and managing diabetic wounds. Highlights * Nanofiber wound dressings provide numerous structural features in biomaterials. * Polycaprolactone can release the repurposed statin molecules into the wound site in a controlled manner. * In diabetic wounds, ECM tissue remodeling stimulates repair and vessel growth. * Pravastatin has been demonstrated to improve angiogenesis and ECM secretion for wound healing in diabetic conditions. KEYWORDS diabetic wounds, electrospinning, hypoxic microenvironment, nanofibers, pro-angiogenesis, re-epithelization, wound dressing, 1 | INTRODUCTION The most prevalent cause of death in diabetic individuals is diabetic wounds. Unfortunately, the bulk of the treatment options in the market do not entirely address how [...]
- Published
- 2024
- Full Text
- View/download PDF
13. The composite metal cluster catalyst Ni–MCM enhances the non-radical pathway for efficient catalytic degradation of norfloxacin.
- Author
-
Xing, Chuhan, Chen, Yaoyao, Song, Zhi, Liu, Boxia, Zhang, Xiayan, Liu, Jialu, Huang, Yeqiong, and Han, Dongxu
- Subjects
- *
METAL catalysts , *METAL clusters , *ANTIBACTERIAL agents , *CHARGE exchange , *METALLIC composites , *ELECTRON paramagnetic resonance spectroscopy - Abstract
Norfloxacin (NOR) is a synthetic antibacterial agent that is extensively applied in the management of various infectious conditions. After entering the human body, most of it cannot be absorbed and is excreted, eventually reaching natural waters. At the same time, it promotes the generation of drug-resistant bacteria, which seriously threatens human health. In this study, a simple mechanical mixing method was employed to synthesize a Ni–MCM composite catalyst with excellent stability, which was utilized for the degradation of NOR. The effects of the mass ratio of Ni–MC to MCM-41, initial pH value, starting NOR concentration, catalyst dosage and inorganic anions on NOR degradation were studied. The findings indicate the superior degradation capability of Ni–MCM towards NOR under diverse conditions. Quenching experiment and electron paramagnetic resonance spectroscopy showed that when dissolved oxygen occupied the active site of the metal in the catalyst, more ˙O2− and 1O2 would be formed, and NOR would be degraded due to the interaction with the mixed system composed of ˙OH and SO4˙− and electron transfer, indicating that the degradation mechanism of the Ni–MCM system was dominated by non-free radicals. The utilization of the Ni–MCM nano-composite catalyst is a promising approach for the treatment of wastewater containing norfloxacin. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
14. Chemical composition and antibacterial activity of essential oils extracted from fresh and dried aerial parts of <italic>Rosmarinus officinalis</italic> L. <italic>Pistacia lentiscus</italic> L. and <italic>Thymus vulgaris</italic> L. from Algeria.
- Author
-
Ouhadda, Hayet, Amrouche, Tahar, Degraeve, Pascal, and Oulahal, Nadia
- Subjects
- *
ESSENTIAL oils , *FOOD preservatives , *ANTIBACTERIAL agents , *STEAM power plants , *PISTACHIO , *LOCAL foods - Abstract
The aim of this study was to determine the chemical composition and antibacterial activity of essential oils (EOs) extracted from local plant by steam distillation from the aerial parts (fresh – dried) of rosemary (
Rosmarinus officinalis L.), pistachio (Pistacia lentiscus L.) and thyme (Thymus vulgaris L.). Monoterpenes were identified by GC-MS as main compounds, namely 1,8-cineole (34.5–35 %), α-pinene (36.2–36.6 %) and thymol (42.2–42.1 %). Our results showed that EOs tested had antibacterial effects at different levels, with MICs ranging from 1.56 to 6.25 mg.mL−1. Fresh rosemary EO was synergistic againstPseudomonas aeruginosa ATCC 27,853 when combined with dried rosemary EO and fresh pistachio EO, with MICs half those of oils alone (from 6.25 to 3.12 mg.mL−1). In addition, antagonistic, additive and indifferent effects were recorded at 1 %, 3 % and 93 %, respectively. Our findings provide new data on antimicrobial potential of local plants and possibilities of their use as food preservatives. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
15. Preparation of extracellular matrix materials with antibacterial activity through incorporating biosynthesized ZnO nanoparticles.
- Author
-
Han, Yuqing, Jiang, Jie, Li, Jinjin, Zhao, Ling, and Xi, Zhenhao
- Subjects
- *
TRANSMISSION electron microscopy , *ANTIBACTERIAL agents , *ZINC chloride , *STAPHYLOCOCCUS epidermidis , *CYTOTOXINS , *TANNINS - Abstract
Extracellular matrix (ECM) with excellent biocompatibility is an ideal biomaterial for tissue repair. However, naturally derived ECM is inefficient in preventing wound infections caused by bacterial invasion. Therefore, developing ECM materials with antibacterial activity is crucial for tissue regeneration. In this work, ZnO–TA nanoparticles (NPs) were synthesized by using tannic acid (TA) and zinc chloride, with an average size of 26.3 nm as investigated by transmission electron microscopy (TEM). Compared to pure ZnO NPs, ZnO–TA NPs have improved dispersibility and lower cytotoxicity. Then, ECM composites were prepared by modifying acellular fish swim bladders (AFSBs) with different concentrations of ZnO–TA NPs and pure ZnO NPs, respectively. Results show that the ZnO–TA NPs are distributed more uniformly in the AFSBs with a longer release behavior. According to the in vitro antibacterial and biocompatibility experiments, ZnO–TA NP-modified AFSBs can maintain sufficient antibacterial activity against Escherichia coli and Staphylococcus epidermidis after 14 and 21 days, respectively, demonstrating a longer-lasting antibacterial activity along with a lower biotoxicity compared with pure ZnO NP-modified AFSBs. These findings suggest that the introduction of biosynthesized ZnO NPs is a promising strategy to improve the antibacterial activity of AFSBs for biomedical applications. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
16. Smart Antibacterial Coatings with On‐Demand Drug Release and Real‐Time Monitoring.
- Author
-
Li, Haotian, Zhang, Linjun, Liang, Bo, Xue, Hongrui, Cao, Huan, Li, Zhen, Yang, Lei, and Li, Yiwen
- Subjects
- *
CONTROLLED release drugs , *ANTIBACTERIAL agents , *DRUG monitoring , *ARTIFICIAL implants , *MEDICAL equipment , *WOUND healing - Abstract
Smart antibacterial coatings with surface‐independent methods, on‐demand antibiotic release, and real‐time drug loading monitoring capabilities have attracted increasing interest in the fields of medical devices, antibiotics delivery platforms, and implantable devices. Addressing the complexity inherent in existing methods, this work innovates by simplifying the synthesis process and integrating aminoglycosides with metallosupramolecules to develop versatile and effective coatings. These coatings not only exhibit exceptional biological activity and efficient antibacterial properties both in vitro and in vivo, but also enable high drug loading and controlled release. Significantly, their application across various devices has demonstrated profound therapeutic effects in treating implant infections and promoting bacterial wound healing. A key advancement of these coatings is the integration of color‐changing indicators for real‐time monitoring of drug levels, enhancing the precision of wound care, and facilitating timely clinical interventions. This research marks a significant stride in the development of more accessible, bioactive, and smart antibacterial materials, opening new avenues in the field of smart medical coatings. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
17. Optimizing β‐lactam‐containing antibiotic combination therapy for the treatment of Buruli ulcer.
- Author
-
D'Agate, Salvatore, Velickovic, Peter, García‐Barrios, Noelia, Ramón‐García, Santiago, and Della Pasqua, Oscar
- Subjects
- *
BURULI ulcer , *ANTIBACTERIAL agents , *CHILD patients , *CLAVULANIC acid , *RIFAMPIN , *CLARITHROMYCIN - Abstract
Aims Methods Results Conclusion The current treatment for Buruli ulcer is based on empirical evidence of efficacy. However, there is an opportunity for shortening its duration and improving response rates. Evolving understanding of the pharmacokinetic–pharmacodynamic relationships provides the basis for a stronger dose rationale for antibiotics. In conjunction with modelling and simulation, it is possible to identify dosing regimens with the highest probability of target attainment (PTA). This investigation aims to: (i) assess the dose rationale for a new combination therapy including amoxicillin/clavulanic acid (AMX/CLV) currently in clinical trials; and (ii) compare its performance with alternative dosing regimens including rifampicin, clarithromycin and AMX/CLV.In vitro estimates of the minimum inhibitory (MIC) concentration were selected as a measure of the antibacterial activity of different drug combinations. Clinical trial simulations were used to characterize the concentration
vs . time profiles of rifampicin, clarithromycin and amoxicillin in a virtual cohort of adult and paediatric patients, considering the effect of baseline covariates on disposition parameters and interindividual variability in exposure. The PTA of each regimen was then assessed using different thresholds of the time above MIC.A weight‐banded dosing regimen including 150–600 mg rifampicin once daily, 250–1000 mg clarithromycin and AMX/CLV 22.5 mg/kg /1000 mg twice daily ensures higher PTA than the standard of care with AMX/CLV 45 mg/kg/2000 mg once daily.The higher PTA values support the proposed 4‐drug combination (rifampicin, clarithromycin, AMX/CLV) currently under clinical investigation. Our findings also suggest that higher rifampicin doses might contribute to enhanced treatment efficacy. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
18. Synergic effect of rare earth doped Sm doped WO3 nanoparticles for enhanced MB dye photocatalytic activities of waste water treatment and antibacterial activities against Staphylococcusaureus.
- Author
-
Subramani, Thangabalu and Nagarajan, Senthil kumar
- Subjects
- *
WATER purification , *WASTE treatment , *PHOTOCATALYSTS , *SEWAGE , *SILVER , *ANTIBACTERIAL agents - Abstract
One of the most effective ways to reduce environmental pollution on the earth's surface is the catalytic decomposition method. In this paper, the co-precipitation method was successfully used to synthesize pure and Sm (3, 5, and 7 wt%) doped WO 3 nanoparticles by various weight percentage. The structural and optical properties of prepared NPs were characterized using XRD, SEM, EDS, HR-TEM, XPS, FTIR and UV–Vis. From XRD analysis confirmed the monoclinic phase of WO 3 as well as the substitutional incorporation of Sm in WO 3 lattice. The surface morphology of the obtained samples was studied by SEM and HR-TEM, which shows nanoplate morphology. EDS and XPS analysis element confirmation for W, O and Sm. The systematic decrease of bandgap (E g) from 2.86 to 2.82 eV with increasing Sm doping concentration from 0 to 7 wt% was strong evidenced from UV–Vis analysis. Furthermore, the extensive surface area of the active CV curves and EIS indicating the good to improve photocatalytic performance and photo-generated carriers' separation efficiency. The photodegradation of Methyl Blue (MB) aqueous solution in 120 min under the visible light irradiation is used to assess the photocatalytic activity of the prepared samples. Among the four samples, 7 wt% doped one shows higher degradation efficiency of 94.2 %. Finally, the antibacterial properties of Sm:WO 3 (0, 3, 5 and 7 wt%) NPs against Staphylococcus aureus (MTCC 8708) were investigated with the disc diffusion method and zone of inhibition in mm were recorded. Based on the above analysis, the superior antibacterial activity against Staphylococcus aureus (18 mm) is rather obtained with Sm:WO 3 (7 wt%) sample. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
19. Enhanced antibacterial activity of poly(vinyl alcohol)‐graphene composites via graphene oxide surfactancy.
- Author
-
Jung, Jae Gu, Kim, Jin Hee, Moon, Juhyung, Kang, Jun Hyeok, Kim, Yu Jin, and Park, Ho Bum
- Subjects
ANTIBACTERIAL agents ,TREATMENT effectiveness ,TISSUE engineering ,THERMAL properties ,BACTERIAL diseases - Abstract
The escalating threat of bacterial infections to human health necessitates innovative antibacterial strategies and materials. Despite this need, there is still a significant demand for materials that combine high mechanical and thermal properties with biocompatibility. To address these urgent issues, our study investigates the development of poly(vinyl alcohol) (PVA) composite with graphene flakes (GF) as fillers. The aim is to strengthen the unique properties of graphene to enhance antibacterial activity. Graphene oxide (GO) was used as a surfactant to achieve stable graphene dispersion in water, preserving its inherent properties while avoiding the drawbacks associated with common surfactants, such as property reduction and complex removal processes. In this study, the mechanical and thermal properties of PVA composites containing GO and GF are superior to those of pristine PVA. Especially, the PVA‐2 composite exhibited a notable enhancement in both tensile strength and elongation at break compared with the PVA composite, with increases of 7.8% and 15% respectively. Moreover, PVA‐2, 4, and 6 composites exhibit significant antibacterial efficacy, achieving 4.8 and 4.9 log CFU/cm2 for Staphylococcus aureus and Escherichia coli, respectively. These results indicate that the enhanced oxidative stress induced by GO as a surfactant, combined with the physical damage caused by the increased GF nanostructures. This study highlights the potential of PVA/GF/GO composites in biomedical and tissue engineering applications, providing a promising pathway for the development of new antibacterial materials. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
20. Synthesis and evaluation of in vitro antioxidant, anticancer, and antibacterial properties of new benzylideneiminophenylthiazole analogues.
- Author
-
Khoshbakht, Ali, Shiran, Jafar Abbasi, Miran, Mansour, and Sepehri, Saghi
- Subjects
- *
ESCHERICHIA coli , *CYTOTOXINS , *SMALL molecules , *MOLECULAR structure , *ANTIBACTERIAL agents - Abstract
A series of new benzylideneiminophenylthiazole analogues were designed and synthesized. Common spectroscopic methods, such as FT-IR, 1H-, 13C-NMR, and MASS spectra, and elemental analysis, were used to confirm the molecular structures. Then, the antioxidant, cytotoxicity, and anti-bacterial effects of synthesized analogues were assessed against 2,2-diphenyl-1-picrylhydrazyl (DPPH), three cancer cell lines, and two bacterial strains, respectively. Among the analogues, 7f was detected as the most potent compound for antioxidant activity. Moreover, the compounds 7b, 7f, and 7 g exhibited the maximum cytotoxicity activity against MCF-7, HepG-2, and A549 cell lines, respectively. Finally, 7e showed the highest anti-bacterial activity against both S. aureus and E. coli strains. It was concluded from the antioxidant, cytotoxicity, and anti-bacterial effects that the benzylideneiminophenylthiazoles might serve as candidate molecules for the development of small molecules with medicinal potential. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
21. Antibacterial effect and mechanism of theaflavin against Listeria monocytogenes and its application on apple skins.
- Author
-
Lin, Yunzhi, Shen, Cunkuan, Zhao, Junxin, Wang, Chen, Obara, Manami, Maung, Aye Thida, Morita, Miho, Abdelaziz, Marwa Nabil Sayed, Masuda, Yoshimitsu, Honjoh, Ken‐ichi, and Miyamoto, Takahisa
- Subjects
- *
MEMBRANE potential , *LISTERIA monocytogenes , *FOOD pathogens , *ANTIBACTERIAL agents , *BIOFILMS - Abstract
Theaflavin 3,3′‐digallate (TF3), a major polyphenolic component of black tea, exhibits antibacterial effects against many foodborne pathogens. However, the antibacterial mechanisms of TF3 against
Listeria monocytogenes remain unclear. In this study, we investigated the effects of TF3 on viability, biofilm, and membrane function ofL. monocytogenes by the conventional plating method, crystal violet staining, and microscopy using fluorescent dyes JC‐1 and Laurdan, respectively. It was found that TF3 showed excellent antibacterial activity againstL. monocytogenes with the minimum inhibitory concentration of 62.5 mg/L. The viable count determined on TSA decreased by 3 log after the treatment for 2 h with TF3 at 62.5 mg/L. The viable count determined on TSA containing 4% NaCl decreased by more than 4 log after the treatment for 30 min with TF3 at the same concentration, suggesting that TF3 gave damage on the cells, enhancing the antibacterial action of 4% NaCl, but the damage was recoverable in the absence of 4% NaCl. To explore the antibacterial mechanisms of TF3, the effects of TF3 on membrane potential and membrane fluidity were investigated. TF3 reduced both membrane potential and fluidity ofL. monocytogenes at 62.5 mg/L, suggesting that TF3 damaged the structural integrity of the cell membrane. TF3 reduced biofilm mass of mature biofilm ofL. monocytogenes . Moreover, THEAFLAVIN TF40, a commercially availableCamellia sinensis leaf extract containing TF3, reduced viable count of L. monocytogenes by 2 log on apple skin. These results suggest the potential of theaflavins as a natural anti‐Listeria disinfectant. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
22. Design, Synthesis and In-Vitro Antimicrobial and Cytotoxic Activity Screening of 5-Carboxamide Substituted 3, 4-Dihydropyrimidine-2 (1H) Ones.
- Author
-
Soleimani Zar, Fereshteh, Dilmaghani, Karim A., and Sarveahrabi, Yasin
- Subjects
- *
ANTIBACTERIAL agents , *MASS spectrometry , *ANTI-infective agents , *AROMATIC aldehydes , *CELL lines - Abstract
AbstractThis paper describes the synthesis and
in vitro biological evaluation of new compounds designated as5(a-h) and8(a-f) . These compounds were synthesized by the reaction of thiazole derivative(3) or thiadiazole derivative(7) with urea and various aromatic aldehydes4(a-h) in ethanol. The structures of the synthesized compounds were checked by IR,1H,13C NMR, and Mass spectroscopy. The antibacterial and antifungal activities of the compounds were evaluated againstEscherichia coli (Gram-negative),Staphylococcus aureus (Gram-positive), andCandida albicans (fungus) using agar well diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal/fungicidal concentration methods. The cytotoxic activities of these compounds against HT-29 and A-549 cancer cell lines were assessedin vitro by the MTT method. Our studies showed compounds8c and8f to have the most expressed antibacterial activity againstS. aureus , while compounds8c and8d were the most potent againstE. coli . Compounds5h and8e showed the highest antifungal activity againstC. albicans , and compound5f showed the most potent activity against the tested cancer cell lines. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
23. Nanoparticle Decorated Cellulose Nanocrystals (CNC) Composites for Energy, Catalysis, and Biomedical Applications.
- Author
-
Raghuwanshi, Vikram Singh and Garnier, Gil
- Subjects
- *
NANOPARTICLES , *DISCONTINUOUS precipitation , *PRODUCTION methods , *ANTIBACTERIAL agents , *ENERGY storage , *CELLULOSE nanocrystals - Abstract
Decorating cellulose nanocrystals(CNC) with nanoparticles(NPs) allows to engineer novel CNC/NPs composites for advanced technologies and applications. NPs are well‐known for their unique and highly efficient properties. However, NPs present challenges and limitations due to their aggregation, non‐uniform growth, size distribution, and nanotoxicity. CNC surface overcomes most of these drawbacks by providing an attractive matrix/template to grow NPs of desirable morphology, distribution, and functionality. CNC has distinctive properties such as biodegradability, high surface area, low cost, good mechanical strength, surface functionality, and chiral nematic self‐assembly. CNC/NPs composites combine the unique properties of both CNC and NPs. This review highlights the unique characteristics of CNC, NPs, and their composites for energy, catalysis, and biomedical applications. First, different production methods for CNC with their effect on morphology, crystallinity index, and yield are presented. Both organic and inorganic NPs are used to decorate either a pristine or a functionalized CNC surface. In situ nucleation and growth methods are compared with the direct incorporation of pre‐formed NPs on the CNC surface. Applications of CNC/NPs composites are reviewed for energy storage material, conductive materials, catalysts, antibacterial agents, biosensors, and bioimaging. Finally, the current challenges and perspectives are presented for unleashing new possibilities in developing functional CNC‐NPs composites. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
24. Preparation and characterization of MgAl2O4 nanoparticles by hydrothermal method and their photocatalytic and antibacterial activity applications.
- Author
-
Chitra, Vaithiyalingam Pakkirisamy, Vasantharani, P., Sivakumar, Ganesan, Santhamoorthy, Madhappan, Guganathan, Loganathan, Devanesan, Sandhanasamy, AlSalhi, Mohamad S., and Palaniappan, Sathish Kumar
- Subjects
- *
PHOTOCATALYSTS , *ANTIBACTERIAL agents , *NANOPARTICLES , *METAL bonding , *METAL detectors - Abstract
In this study, MgAl 2 O 4 nanoparticles were prepared by the hydrothermal method. XRD studies confirmed the presence of cubic crystal structure with no other impurities at higher reaction times. The calculated crystallite size decreased from 22 to 12 nm with the increase in reaction times. FTIR analysis confirmed the nature of their structure bonding and the metal oxides detected below 1000 cm−1. FESEM and HRTEM images revealed the MgAl 2 O 4 sample showed hexagonal plate structures and the SAED pattern exhibited polycrystalline in nature. EDS analysis confirmed the presence of Mg, Al and O elements. The chemical and oxidation state of the constituents were revealed by XPS (Mg2+). The UV–vis results of prepared samples showed a strong absorption edge in the visible region and bandgap values were increased from 3.05 to 3.46 eV. 24 hrs of MgAl 2 O 4 photocatalyst material showed better photocatalytic properties in degrading RhB dye was 80 % after 140 min of irradiation. Moreover, the results derived from antibacterial activity revealed that 24 h of MgAl 2 O 4 nanoparticles high incubation zone against Staphylococcus aureus. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
25. Production Sericin/Poly(Vinyl Alcohol) Blend Membranes Containing One‐Step Synthesized Silver Nanoparticles by UV Radiation for Obtaining Versatile Antibacterial Materials.
- Author
-
Temel, Aleyna, Nuran Doğan, Hatice, Yıldız, Emine, Yanık, Gizem, and Gün Gök, Zehra
- Subjects
- *
FIELD emission electron microscopy , *ANTIBACTERIAL agents , *SERICIN , *COMPOSITE membranes (Chemistry) , *ULTRAVIOLET radiation , *SILVER - Abstract
In this study, silver nanoparticles (AgNPs) were in‐situ synthesized in silk sericin/poly(vinyl alcohol) (SS/PVA) mixtures by an easy one‐step synthesis method with the presence of ultraviolet (UV) radiation. Then, the SS/PVA composite membranes containing AgNPs were obtained by solvent casting method. The chemical structures of the membranes were investigated by fourier‐transform infrared spectroscopy (FTIR) and results showed that the membranes were a mixture of silk sericin and PVA. The morphological features of the membranes were investigated by field emission scanning electron microscopy (FE‐SEM) and it was seen that AgNPs containing membranes have heterogeneous structures. Energy dispersive spectroscopy (EDS) analysis revealed that the membranes contain carbon, oxygen, nitrogen, sulfur and silver. X‐ray diffractometer (XRD) and thermogravimetric (TGA) analyses also proved the presence of AgNPs in the structure of membranes. The antibacterial activities of membranes containing AgNPs were investigated on Staphylococcus aureus and Escherichia coli bacteria with disk diffusion test and liquid culture medium incubation. It was found that SS/PVA membranes containing 5 and 10 mM AgNPs have quite high antibacterial activity on both types of bacteria. The functional SS/PVA membranes have capacity to be used in biomedical applications such as wound care materials. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
26. Synthesis, Antifungal, Antibacterial and Antioxidant Activities of New Pyrazolo‐Triazaphophosphorin‐2‐Oxide Derivatives.
- Author
-
Louiz, Sonia and Abderrahim, Raoudha
- Subjects
- *
BENZYL bromide , *ALTERNARIA alternata , *ANTIBACTERIAL agents , *CORTISONE , *KETONE derivatives , *ANTIFUNGAL agents - Abstract
The current work describes the synthesis, characterization and antimicrobial evaluation of a new series of pyrazolo‐triazaphosphorine derivatives. The synthesized compounds were confirmed by NMR (1H,13C,31P), IR spectroscopy, by elemental analysis and LCMS. The series of phosphorus products were screened for their antifungal activities and for their antibacterial activities. Finally, the antioxidant activity was tested for one of them (2a). The results were compared with biological activities of some drugs and demonstrate that the antibacterial and antifungal activities of 2 a–f, are influenced by the variation of the group R, R' and the donor or attractor effects of the group R′. Likewise, the donor effect of the group in compound 2 e has a positive influence on the antifungal activity and 2 e reacts against Alternaria alternata with the lowest IC50=0.795 μg mL−1 than drug. The phosphorus products can be used as some antibacterial and antifungal agents and one of the compounds(2a) have an excellent antioxidant power. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
27. Green synthesis of polyethylene glycol coated, ciprofloxacin loaded CuO nanoparticles and its antibacterial activity against Staphylococcus aureus.
- Author
-
Ibne Shoukani, Hussan, Nisa, Sobia, Bibi, Yamin, Ishfaq, Afsheen, Ali, Ashraf, Alharthi, Sarah, Kubra, Khudija tul, and Zia, Muhammad
- Subjects
- *
FOURIER transform infrared spectroscopy , *X-ray diffraction , *PLANT extracts , *STAPHYLOCOCCUS aureus , *CYTOTOXINS , *ANTIBACTERIAL agents , *CIPROFLOXACIN - Abstract
Antibacterial resistance requires an advanced strategy to increase the efficacy of current therapeutics in addition to the synthesis of new generations of antibiotics. In this study, copper oxide nanoparticles (CuO-NPs) were green synthesized using Moringa oleifera root extract. CuO-NPs fabricated into a form of aspartic acid-ciprofloxacin-polyethylene glycol coated copper oxide-nanotherapeutics (CIP-PEG-CuO) to improve the antibacterial activity of NPs and the efficacy of the drug with controlled cytotoxicity. These NPs were charachterized by Fourier transform infrared spectroscopy (FTIR), x-rays diffraction spectroscopy (XRD), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). Antibacterial screening and bacterial chemotaxis investigations demonstrated that CIP-PEG-CuO NPs show enhanced antibacterial potential against Gram-positive and Gram-negative clinically isolated pathogenic bacterial strains as compared to CuO-NPs. In ex-vivo cytotoxicity CIP-PEG-CuO-nano-formulates revealed 88% viability of Baby Hamster Kidney 21 cell lines and 90% RBCs remained intact with nano-formulations during hemolysis assay. An in-vivo studies on animal models show that Staphylococcus aureus were eradicated by this newly developed formulate from the infected skin and showed wound-healing properties. By using specially designed nanoparticles that are engineered to precisely transport antimicrobial agents, these efficient nano-drug delivery systems can target localized infections, ensure targeted delivery, enhance efficacy through increased drug penetration through physical barriers, and reduce systemic side effects for more effective treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
28. Lipase-mediated alcoholysis for in situ production of ester bioaromas in licuri oil for cosmetic applications.
- Author
-
Moreira, Rafael Chelala, Leonardi, Gislaine Ricci, and Bicas, Juliano Lemos
- Subjects
- *
ESTERS , *TROPICAL fruit , *ALCOHOLYSIS , *ANTIBACTERIAL agents , *BIOCONVERSION , *LIPASES , *ETHYL esters - Abstract
Bioaromas can be produced by lipases either through their hydrolytic or (trans)esterifying activities. Therefore, this work reports the development of a lipase-catalyzed biotransformed licuri oil, forming volatile ethyl esters with odor notes resembling tropical fruits. Ethyl octanoate formation was promoted when 7.0 % (m/v) Lipozyme 435® was used to convert a grain alcohol:licuri oil mixture (51:49, v/v) at 58ºC and 70 rpm for 6 hours. The biotransformed oil has shown antimicrobial activity against Staphylococcus hominis , S. epidermidis, and Corynebacterium xerosis , bacteria associated with bad skin odor. Finally, this biotransformed oil was used without further treatments (e.g., recovery or purification procedures) to prepare two cosmetic formulations (in a dosage of 1.5 %), aiming for both fragrant and deodorant activity. • Odor-active ethyl esters were formed in lipase-biotransformed licuri oil. • 8.22 g/L ethyl octanoate was formed with 7 % lipase, 51:49 alcohol:oil ratio at 58°C. • Antibacterial activity of biotransformed oil could prevent bad skin odor. • Cosmetic formulations were prepared with 1.5 % biotransformed licuri oil. • No purification procedures were needed to use a natural fragrant mixture. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
29. Grewiifopenes A–K, bioactive clerodane diterpenoids from Casearia grewiifolia Vent.
- Author
-
Pailee, Phanruethai, Batsomboon, Paratchata, Yaosanit, Wiriya, Thananthaisong, Theerawat, Mahidol, Chulabhorn, Ploypradith, Poonsakdi, Reuk-ngam, Nanthawan, Khlaychan, Panita, Techasakul, Supanna, Ruchirawat, Somsak, and Prachyawarakorn, Vilailak
- Subjects
DITERPENES ,BACILLUS cereus ,ANTIBACTERIAL agents ,CIRCULAR dichroism ,PERMUTATION groups - Abstract
Eleven novel clerodane-type diterpenoids, grewiifopenes A–K (1–4 and 12–18), along with nine known compounds (5–11, 19, and 20) were purified from the dichloromethane extract of the twigs and stems of Casearia grewiifolia Vent. (Salicaceae). Their spectroscopic data, including the NMR, HRESIMS, and electronic circular dichroism calculations were employed to completely characterize and elucidate the chemical structures and absolute configurations. The clerodane diterpenoids possessing a 6-OH group and no substitution at C-7 exhibited greater cytotoxic activity than others, with their IC
50 values ranging from 0.3 to 2.9 μM. Isocaseamembrin E (7) exhibited antibacterial activity against Staphylococcus aureus, while isocaseamembrin E (7), corymbulosin X (8), caseargrewiin A (9), kurzipene A (10), and balanspene F (11) exhibited antibacterial activity against Bacillus cereus. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
30. Synthetic and theoretical study on novel N-ylidic complexes of mercury as new antibacterial agents.
- Author
-
Bayat, Zahra, Yousefi, Abed, Sabounchei, Seyyed Javad, Ahmadvand, Zeinab, Bayat, Mehdi, Khoei, Masoumeh Ahmadi, and Gable, Robert W.
- Subjects
- *
NATURAL orbitals , *GRAM-negative bacteria , *X-ray diffraction , *ANTIBACTERIAL agents , *PYRIDINE - Abstract
The novel structure of Hg(II) complexes including the pyridinium ylide C5H5NCHC(O)C6H4-m-Br (Y) were synthesized and reported in this study. In the first step, the pyridinium salt C5H5NCH2C(O)C6H4-m-Br (S) was produced by reacting 2,3′-dibromoactophenone and pyridine. then, treatment of S with K2CO3 gave the related pyridinium ylide Y. Finally, the reaction of Y with HgX2 and Hg(NO3)2·H2O leads to the formation of novel binuclear [HgY2][HgX4] (X=Cl (1); X=Br (2); X=I (3)) and polymeric [HgY(NO3)2]n (4) complexes. The structure of complex 2 was also determined by X-ray diffraction analysis. The obtained analyses proved the coordination through the ylidic carbon to metallic center. Additionally, Natural Bond Orbital (NBO), Energy Decomposition Analysis (EDA), and EDA-NOCV studies are also used to investigate the nature of metal–ligand bonding in the complexes. Finally, the antibacterial activity of 1–4 was also examined against Gram positive and negative represented significant levels of inhibitory potency respected to used standards. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
31. Construction of a supramolecular antibacterial material based on water-soluble pillar[5]arene and a zwitterionic guest molecule.
- Author
-
Liu, Haoming, Lv, Jinmeng, Wang, Xue, Dong, Shengyi, Li, Xinyun, and Gao, Lingyan
- Subjects
- *
COLUMNS , *ANTIBACTERIAL agents , *ESCHERICHIA coli , *HOST-guest chemistry , *MOLECULES , *MERCURY - Abstract
A new antibacterial system (HG) based on the host–guest chemistry between pillar[5]arene and a zwitterionic guest was fabricated. The HG complex displayed excellent antibacterial and biofilm formation inhibition and dispersal activities against E. coli, S. aureus and MRSA. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
32. Catalytic activity of HKUST-1 for the synthesis of fused N-heterocycles under microwave irradiation and studies of their in vitro anti-bacterial and anti-tubercular activities.
- Author
-
Goswami, Munmee, Paul, Pooja, Nongkhlaw, Ridahunlang, Kumari, Jyothi, Sriram, Dharmarajan, and Nongkhlaw, Rishanlang
- Subjects
- *
CATALYTIC activity , *SUSTAINABLE chemistry , *ANTIBACTERIAL agents , *ESCHERICHIA coli , *GRAM-negative bacteria - Abstract
Strategies facilitating the synthesis of heterocycles using green methodologies have modernized their syntheses in synthetic and pharmaceutical chemistry. In the present study, a highly well-organized, ecofriendly and straightforward synthetic approach was developed for the microwave-assisted synthesis of fused pyrazolopyridines and spirooxindole-fused pyrazolopyridines using an economical metal--organic framework, HKUST-1, in ethanol. The prepared MOF was characterized through diverse techniques, including FT-IR, p-XRD, SEM, TEM, EDX, TGA and BET. This approach shows noteworthy advantages, such as good yields, simple and clean reaction conditions, shorter reaction time, use of a highly efficient and sustainable catalyst and no chromatographic separation as the entire products can be purified through recrystallization. Moreover, green chemistry metrics for compounds 4a, 6a, 8a and 9a were calculated and were found to be very close to ideal values. The TON and TOF of the catalyst reached 32.75 and 3.27 min-1, respectively, for this transformation. In vitro anti-bacterial screening of these synthesized derivatives was performed against the Gram-negative bacteria Escherichia coli (E. coli) and Gram-positive bacteria Staphylococcus aureus (S. aureus). Compounds 4a and 6f showed activity against all the bacteria tested in the experiment. Further, the anti-tubercular study of the synthesized compounds revealed that compound 4b had the highest activity among all the synthesized derivatives. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
33. Molecular Characterization and Antibacterial Potential of Endophytic Fungal Isolates from Selected Mangroves along the Coastline of Kenya.
- Author
-
Wacira, Teresia Nyambura, Makonde, Huxley Mae, Bosire, Carren Moraa, Kibiti, Cromwell Mwiti, and Dilarri, Guilherme
- Subjects
- *
DRUG discovery , *PLANT extracts , *ETHYL acetate , *ANTIBACTERIAL agents , *PSEUDOMONAS aeruginosa , *ENDOPHYTIC fungi - Abstract
The increasing emergence and re‐emergence of resistant pathogenic microbes causes a health threat to the human population. Scientists have been striving to find novel bioactive compounds and drugs to overcome these obstacles. This study aimed to characterize mangrove endophytic fungi and evaluate their antibacterial activity. Heritiera littoralis, Rhizophora mucronata, Bruguiera gymnorrhiza, Avicennia marina, and Xylocarpus granatum species were collected from Tudor Creek, Mida Creek, and Gazi Bay. A total of 30 fungal isolates were subjected to molecular identification based on analysis of their ITS gene region. The isolates in the inferred phylogenetic trees were affiliated with the genus Aspergillus. Ethyl acetate and butanol crude extracts of 38.2% of the 76 isolated fungal endophytes and eight mycelia samples were screened for antibacterial activity against Staphylococcus aureus (ATCC 27853), Escherichia coli (ATCC 25922), and Pseudomonas aeruginosa (ATCC 25923) using the disc diffusion method. A. marina and R. mucronata harbored the most fungal endophytes that showed the highest antibacterial activity. Seven fungal broth extracts exhibited higher antibacterial activities against the tested microorganisms than the positive control. The minimum inhibitory concentration (MIC) activity for the isolates demonstrated that the ethyl acetate extract of a root endophytic fungal isolate (RC6) (3.31 ± 0.01) of A. marina is a strong inhibitor since it showed significantly lower MIC activity compared to the positive control (3.84 ± 0.00) against Pseudomonas aeruginosa (P < 0.05). Therefore, this study confirms that mangrove species harbor fungal isolates that have antibacterial activity and hence could serve as a novel source of antibiotics. It is recommended that the pure compounds from these extracts be isolated for further bioactivity tests and structural elucidation for consideration as lead molecules in drug discovery. In addition, the genes responsible for the enhanced bioactivity in these isolates can be characterized and bioengineered for pharmaceutical application. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
34. Ursolic and oleanolic acids: two natural triterpenoids targeting antibacterial multidrug tolerance and biofilm formation.
- Author
-
Spaggiari, Chiara, Annunziato, Giannamaria, and Costantino, Gabriele
- Subjects
URSOLIC acid ,TRITERPENOIDS ,ANTIBACTERIAL agents ,MULTIDRUG tolerance (Microbiology) ,BIOFILMS - Abstract
Natural products have been used since ancient times to treat various ailments and have been recognized for many years as a source of therapeutic agents and structural diversity. Plant-derived products have thus served as dietary components but also to maintain a state of wellbeing and health by preventing different diseases both of inflammatory and infective nature. Pentacyclic triterpenoids, particularly ursolic acid (UA) and oleanolic acid (OA), are well-studied natural products endowed with complex biological profiles. In this mini-review, we summarized the most advanced results on extraction methodologies and antimicrobial activity of UA and OA, focusing on their potential role as antimicrobic adjuvants, bacterial biofilm inhibitors and related mechanisms of action. This offers a theoretical basis and inspiration for further studies on their bioactivity mechanism. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
35. Silver nanoparticles incorporated with enzymatically derived chitooligosaccharides: preparation, characterization, and biological potential evaluation.
- Author
-
Affes, Sawsan, Aranaz, Inmaculada, Acosta, Niuris, Heras, Ángeles, Nasri, Moncef, and Maalej, Hana
- Subjects
SILVER nanoparticles ,TRANSMISSION electron microscopy ,ULTRAVIOLET-visible spectroscopy ,LIGHT scattering ,ANTIBACTERIAL agents - Abstract
In this work, silver nanoparticles (AgNPs) were elaborated using a simple, low-cost, and reproducible method by thermal treatment at 90°C of chitooligosaccharides (COSs), produced by chitosan depolymerization using the digestives chitosanases from Portunus segnis viscera, in the presence of AgNO3. The characterization of the obtained AgNPs, using UV-visible spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier-transform infrared (FTIR) spectroscopy analyses, showed that they are crystalline, spherical and stable for a month at 4°C. Moreover, the biological properties of the synthesized AgNPs were evaluated, proving that they exhibited interesting antioxidant and antibacterial activities. The present investigation suggested that COSs will be a good source for the preparation of AgNPs that could be useful in different industrial and biomedical applications. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
36. Blue fluorescent waterborne polyurethane‐based transition metal complexes with antibacterial activity.
- Author
-
Hu, Hongrui, Cheng, Bo, Yang, Mingdi, Zhang, Kehua, Chen, Jianli, Wang, Ping, Yang, Yuqing, Ding, Yunsheng, Gong, Chengbing, and Hu, Xianhai
- Subjects
TRANSITION metal complexes ,BLUE light ,ANTIBACTERIAL agents ,TRANSITION metal ions ,COPPER ,LIGANDS (Chemistry) ,THERMAL stability - Abstract
Efficient and stable blue fluorescent materials are the key components of light‐emitting devices and have received wide attention. Herein, transition metal complexes Zn(5‐AQ)2, Cu(5‐AQ)2, and Cd(5‐AQ)2 are prepared by using 5‐aminoquinoline (5‐AQ) as ligand and Zn2+, Cu2+, and Cd2+ as the central ions, respectively. Then, waterborne polyurethane (WPU)‐based transition metal complexes Zn(5‐AQ)2‐WPU, Cu(5‐AQ)2‐WPU, and Cd(5‐AQ)2‐WPU with different emission wavelengths of blue fluorescence are prepared by bonding Zn(5‐AQ)2, Cu(5‐AQ)2, and Cd(5‐AQ)2 to polyurethane chains as chain extenders, respectively. Noteworthily, with the increase of transition metal ion radius (Zn2+ < Cu2+ < Cd2+), the fluorescence emission wavelengths of the complexes showed different degrees of blue‐shift, and the blue‐shifted wavelengths showed a decreasing trend. Importantly, their fluorescence colors are blue‐shifted from blue‐green to blue with different emission wavelengths after accessing the polyurethane backbone, which has potential applications in the field of tuning white LED materials. The thermal decomposition temperatures of Zn(5‐AQ)2‐WPU, Cu(5‐AQ)2‐WPU, and Cd(5‐AQ)2‐WPU are above 220°C with good thermal stability, and their fluorescence lifetimes are prolonged by 8.817, 8.896, and 6.489 ns, respectively, compared with the complexes. Furthermore, WPU transition metal complexes with water as a dispersive medium have an antibacterial efficiency of up to 100% against Escherichia coli, which is an environmentally friendly antibacterial material with broad application prospects. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
37. Clinical outcome of ampicillin or ampicillin/sulbactam versus glycopeptides in ampicillin-susceptible Enterococcus faecalis/faecium bacteremia: a 10-year retrospective cohort study.
- Author
-
Seong, Yeol Jung, Song, Je Eun, Lee, Eugene, Kim, Eun Jin, Heo, Jung Yeon, Choi, Young Hwa, and Kim, Yong Chan
- Subjects
- *
ENTEROCOCCUS faecalis , *LOGISTIC regression analysis , *ANTIBACTERIAL agents , *BACTEREMIA , *TREATMENT effectiveness , *ENTEROCOCCAL infections - Abstract
Background: Glycopeptides for ampicillin-susceptible Enterococcus faecalis/faecium bacteremia are readily prescribed depending on the severity of the condition. However, there is limited data on the outcomes of glycopeptide use compared to ampicillin-containing regimens for ampicillin-susceptible E. faecalis/faecium bacteremia. From an antibiotic stewardship perspective, it is important to determine whether the use of glycopeptides is associated with improved clinical outcomes in patients with ampicillin-susceptible E. faecalis/faecium bacteremia. Methods: This retrospective cohort study was conducted at a university-affiliated hospital between January 2010 and September 2019. We collected data from patients with positive blood cultures for Enterococcus species isolates. The clinical data of patients who received ampicillin-containing regimens or glycopeptides as definitive therapy for ampicillin-susceptible E. faecalis/faecium bacteremia were reviewed. Multivariate logistic regression analysis was performed to identify risk factors for 28-day mortality. Results: Ampicillin-susceptible E. faecalis/faecium accounted for 41.2% (557/1,353) of enterococcal bacteremia cases during the study period. A total of 127 patients who received ampicillin-containing regimens (N = 56) or glycopeptides (N = 71) as definitive therapy were included in the analysis. The 28-day mortality rate was higher in patients treated with glycopeptides (19.7%) than in those treated with ampicillin-containing regimens (3.6%) (p = 0.006). However, in the multivariate model, antibiotic choice was not an independent predictor of 28-day mortality (adjusted OR, 3.7; 95% CI, 0.6–23.6). Conclusions: Glycopeptide use was not associated with improved mortality in patients with ampicillin-susceptible E. faecalis/faecium bacteremia. This study provides insights to reduce the inappropriate use of glycopeptides in ampicillin-susceptible E. faecalis/faecium bacteremia treatment and promote antimicrobial stewardship. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
38. Evaluation of the cytotoxicity and antibacterial activity of nano-selenium prepared via gamma irradiation against cancer cell lines and bacterial species.
- Author
-
Salah, M., Elkabbany, Nesreen A. S., and Partila, Abir M.
- Subjects
- *
CYTOTOXINS , *CELL lines , *KLEBSIELLA pneumoniae , *ELECTRON paramagnetic resonance , *ANTIBACTERIAL agents , *CANCER cells - Abstract
A recent scientific investigation has shown promising results of selenium nanoparticles (SeNPs) for the anticancer and antimicrobial activities. This study aims to evaluate the effects of PVP SeNPs on bacterial strains, including Staphylococcus aureus (S. aureus), Bacillus cereus (B. cereus), Klebsiella pneumoniae (K. pneumoniae), Escherichia coli (E. coli), and Pseudomonas aeruginosa (P. aeruginosa). Also, its antitumor activity against the MRC-5 carcinoma cell line. SeNPs were prepared via gamma irradiation using PVP as a capping agent, and their size and morphological structure were determined using HRTEM. The size of the SeNPs ranged from 36 to 66.59 nm. UV–vis spectra confirmed the formation of SeNPs, while FTIR measurement confirmed a change in the PVP structure after adding selenium nanoparticles. The highest effect was reported on HepG2 by an IC50 with a value of 8.87 µg/ml, followed by HeLa, PC3, MCF-7, and Caco2 cell lines, respectively. Furthermore, ZOI reached 36.33 ± 3.05 mm. The best value of the minimum inhibitory concentration (MIC) was 0.313 µg/ml. Scanning electron microscope (SEM) imaging against bacteria showed deformations and distortions in their structures. Transmission electron (TEM) revealed ultrastructure changes in treated bacteria because of the free radicals that made cytotoxicity which confirmed by Electron spin resonance (ESR). [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
39. Antibacterial Activity of Ag+ on ESKAPEE Pathogens In Vitro and in Blood.
- Author
-
Garry, Brittany, Thanapaul, Rex J R Samdavid, Werner, Lacie M, Pavlovic, Radmila, Rios, Kariana E, Antonic, Vlado, and Bobrov, Alexander G
- Subjects
- *
ENTEROCOCCUS faecium , *ACINETOBACTER baumannii , *ESCHERICHIA coli diseases , *GRAM-negative bacteria , *ANTIBACTERIAL agents - Abstract
Introduction Bloodstream infections are a significant threat to soldiers wounded in combat and contribute to preventable deaths. Novel and combination therapies that can be delivered on the battlefield or in lower roles of care are urgently needed to address the threat of bloodstream infection among military personnel. In this manuscript, we tested the antibacterial capability of silver ions (Ag+), with long-appreciated antibacterial properties, against ESKAPEE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter species, and Escherichia coli) pathogens. Materials and Methods We used the GENESYS (RAIN LLC) device to deliver Ag+ to Gram-positive and Gram-negative ESKAPEE organisms grown in broth, human blood, and serum. Following the Ag+ treatment, we quantified the antibacterial effects by quantifying colony-forming units. Results We found that Ag+ was bactericidal against 5 Gram-negative organisms, K pneumoniae, A baumannii, P aeruginosa , E cloacae , and E coli , and bacteriostatic against 2 Gram-positive organisms, E faecium and S aureus. The whole blood and serum inhibited the bactericidal activity of Ag+ against a common agent of bloodstream infection, P aeruginosa. Finally, when Ag+ was added in conjunction with antibiotic in the presence of whole blood, there was no significant effect of Ag+ over antibiotic alone. Conclusions Our results confirmed that Ag+ has broad-spectrum antibacterial properties. However, the therapeutic value of Ag+ may not extend to the treatment of bloodstream infections because of the inhibition of Ag+ activity in blood and serum. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
40. PLGA Nanoparticles Formulations Loaded With Antibiotics Induce Sustained and Controlled Antibiotics Release for Prolonged Antibacterial Action Against MRSA, and Pseudomonas aeruginosa FRD1.
- Author
-
Guevara, Argerie, Armknecht, Kevin, Kudary, Carlie, and Nallathamby, Prakash
- Subjects
- *
ANTIBACTERIAL agents , *METHICILLIN-resistant staphylococcus aureus , *ACINETOBACTER baumannii , *TREATMENT effectiveness , *DRUG delivery systems , *GLYCOLIC acid - Abstract
The purpose of the present study was to create resorbable nanoparticles (NPs) using poly(lactic-co-glycolic acid) (PLGA) to develop novel antibacterial therapeutics for the treatment of chronic wound infections that are susceptible to recurrent infections. By first performing a release study, it was possible to predict the behavior of the different PLGA NP formulations and assess the efficacy of the nanocomposite drug delivery system. These PLGA NP formulations consisted of varying ratios of PLGA without polyvinyl alcohol (PVA) and PLGA with PVA (PLGA-PVA) (i.e. 25:75[PLGA25], 50:50[PLGA50], and 75:25[PLGA75]). Then, different antibiotics (i.e. ciprofloxacin and gentamicin) were incorporated into the PLGA NP formulations to test the antibacterial efficacy of these antimicrobial NPs against different pathogens (i.e. methicillin-resistant Staphylococcus aureus USA300 [MRSA], Pseudomonas aeruginosa FRD1, and Acinetobacter baumannii BAA1605). Of particular interest was testing against the MRSA strain USA300 and the P. aeruginosa strain FRD1. This was possible by measuring the zone of inhibition. A 3-day period was used to monitor the antibacterial efficacy of the different PLGA NP formulations (i.e. PLGA25, PLGA50, and a 1:1 combination of PLGA25:PLGA50) against A. baumannii BAA1605 , MRSA, and P aeruginosa FRD1. Throughout the study, A. baumannii was a negative control and was resistant to all the PLGA NP formulations loaded with ciprofloxacin and gentamicin. At the end of the 3-day period, the PLGA and PLGA50 ciprofloxacin-loaded formulations produced zones of inhibition of 27 mm and 23 mm, respectively, against P. aeruginosa FRD1. This indicated that P. aeruginosa FRD1 was susceptible to both formulations. The mixed formulations with equal parts PLGA25:PLGA50 loaded with ciprofloxacin produced a zone of inhibition (i.e. 25 mm). This again indicated that P. aeruginosa FRD1 was susceptible to ciprofloxacin. The formulations tested against MRSA showed that only gentamicin-loaded formulations produced intermediate results, and that ciprofloxacin-loaded formulations were ineffective. The PLGA25 and the PLGA50 NP formulations loaded with gentamicin both produced zones of inhibition of 13 mm. This indicated that MRSA was intermediate to both the formulations. The PLGA25:PLGA50 loaded with gentamicin produced a zone of inhibition of 14 mm, which again showed that MRSA was intermediate to this formulation. Overall, these PLGA NP formulations showed the sustained antibacterial potential of a burst release, followed by a sustained release of antibiotics from antibiotics loaded PLGA NPs in a controlled manner. In the future, this can help prevent the emergence of recurrent infections in the treatment of chronic wounds and reduce the number of medical dressing changes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
41. An Integrative Computational Approach for Design and Evaluation of Novel [1,2,4]triazolo[3,4-b][1,3,4]thiadiazole Analogues as Dual-Action Anti-Retroviral and Anti-Bacterial Agents: Insights into Rational Drug Design Strategies.
- Author
-
Ghosh, Rahul and Ganguly, Swastika
- Subjects
- *
DRUG design , *ANTIRETROVIRAL agents , *MOLECULAR orbitals , *MOLECULAR dynamics , *ANTIBACTERIAL agents - Abstract
The development of effective antiretroviral inhibitors (HIV-1 Reverse Transcriptase) and glucosamine-6-phosphate (GlcN6P) agents represent a significant challenge for combating viral infections and related diseases. In this study, we employed a multidisciplinary approach to design and evaluate a series of novel triazole analogs as potential candidates for anti-retroviral and glucosamine-6-phosphate agents. Using molecular docking, we explored the binding interactions between the RSA3 analog and the target proteins implicated in viral replication and glucosamine metabolism. Density functional theory (DFT) employing the 6-311++G(d,p) basis set was utilized for computational analysis, with a subsequent examination of the electronic parameters. The HOMO and LUMO orbitals as well as the molecular electrostatic potential map were investigated using DFT to characterize the reactivity of our molecule. Molecular dynamics simulations were performed to investigate the stability and dynamic behavior of the ligand-protein complex (RSA3) over time (300 ns). Furthermore, we employed MM-GBSA calculations of the compound RSA3 (molecular mechanics generalized band surface area) to estimate the binding free energies (−71.30 ± 7.26 kcal/mol and −67.86 ± 7.09 kcal/mol, respectively) and identified the most promising compounds with high affinity for the target proteins. Additionally, predictive absorption, distribution, metabolism, excretion and toxicity (ADMET) studies of compound RSA3 were conducted to assess its drug-like properties and potential safety profiles of the selected compound. Our results revealed that RSA3 has favorable binding interactions, is a stable complex and has significant binding affinity for target proteins. Moreover, predictive ADMET studies indicated that RSA3 possesses desirable drug-like properties, suggesting its potential for further investigation as an anti-retroviral agent and glucosamine-6-phosphate agent. Overall, this integrative computational approach combining molecular docking, DFT analysis, dynamics simulations, MM-GBSA and predictive ADMET studies provides valuable insights into the design and evaluation of novel triazole analogs with potential therapeutic applications, highlighting the importance of rational drug design strategies in the field of antiretroviral and glucosamine research. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
42. Biogenic Zinc Oxide Nanoparticles as a Promising Antibacterial Agent: Synthesis and Characterization.
- Author
-
Okaiyeto, Kunle, Gigliobianco, Maria Rosa, and Di Martino, Piera
- Subjects
- *
ZINC compounds synthesis , *ZINC oxide , *STABILIZING agents , *ANTIBACTERIAL agents , *BACTERIAL diseases - Abstract
Nanotechnology has gained popularity in recent years due to its wide-ranging applications within the scientific community. The three main methods for synthesizing nanoparticles are physical, chemical, and biological. However, the adverse effects associated with physical and chemical methods have led to a growing interest in biological methods. Interestingly, green synthesis using plants has gained prominence in developing new treatments for bacterial infections. Zinc oxide nanoparticles (ZnO NPs) produced using environmentally friendly methods are more biocompatible and have potential applications as antibacterial agents in the biomedical field. As a result, this review discusses the green synthesis of ZnO NPs, factors influencing optimal synthesis, characterization techniques, and the antibacterial activity of some plant-mediated ZnO NPs. It also provides a comprehensive and analytical exploration of ZnO NP biosynthesis, the role of phytochemical compounds as reducing and stabilizing agents, the mechanism of action of their antibacterial properties and further highlights the challenges and prospects in this innovative research area. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
43. Neomycin Intercalation in Montmorillonite: The Role of Ion Exchange Capacity and Process Conditions.
- Author
-
Rapacz-Kmita, Alicja, Gajek, Marcin, Dudek, Magdalena, Kurpanik, Roksana, Kluska, Stanisława, and Stodolak-Zych, Ewa
- Subjects
- *
PROCESS capability , *PHARMACOKINETICS , *NEOMYCIN , *ANTIBACTERIAL agents , *INFRARED spectroscopy , *MONTMORILLONITE - Abstract
The study examined the possibility of intercalation of montmorillonite with neomycin in an aqueous drug solution and the factors influencing the effectiveness of this process, such as the ion exchange capacity and process conditions, including the time and temperature of incubation with the drug. X-ray diffractometry (XRD), infrared spectroscopy (FTIR), thermal analysis (DSC/TG), and Zeta potential measurement were used to confirm drug intercalation as well as to investigate the nature of clay–drug interactions. The obtained conjugates with the most favorable physicochemical properties were also tested for antibacterial response against Gram-negative bacteria (Escherichia coli) to confirm that the bactericidal properties of neomycin were retained after intercalation and UV–VIS spectrophotometry was used to examine the kinetics of drug release from the carrier. The results of the conducted research clearly indicate the successful intercalation of neomycin in montmorillonite and indicate the influence of process parameters on the properties of not only the conjugates themselves but also the properties of the intercalated drug, particularly its bactericidal activity. Ultimately, a temperature of 50 °C was found to be optimal for effective drug intercalation and the conjugates obtained within 2 h showed the highest antibacterial activity, indicating the highest potential of the thus-obtained montmorillonite conjugates as neomycin carriers. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
44. New Antibacterial and Antioxidant Chitin Derivatives: Ultrasonic Preparation and Biological Effects.
- Author
-
Egorov, Anton R., Khubiev, Omar M., Golubev, Roman A., Semenkova, Daria I., Nikolaev, Andrey A., Maharramov, Abel M., Mammadova, Gunay Z., Liu, Wanjun, Tskhovrebov, Alexander G., and Kritchenkov, Andreii S.
- Subjects
- *
POLYSACCHARIDES , *CATIONIC polymers , *COUPLING reactions (Chemistry) , *POLYMER testing , *ANTIBACTERIAL agents , *CHITIN - Abstract
This work focuses on the first use of ultrasonic phenol-ene coupling as a polymer analogous transformation. The ultrasonic reaction was introduced into chitin chemistry, resulting in the fast and convenient preparation of new water-soluble cationic chitin derivatives. Since water-soluble derivatives of fully deacetylated chitin are poorly described in the literature, the synthesis of each new type of these derivatives is a significant event in polysaccharide chemistry. Polycations, or cationic polymers, are of particular interest as antibacterial agents. Consequently, the resulting polymers were tested for their antibacterial activity and toxicity. We found that the highly substituted polymer of medium molecular weight exhibited the most pronounced in vitro antibacterial effect. We prepared nanoparticles using the ionic gelation technique. The most effective in vitro antibacterial chitin-based systems were tested in vivo in rats. These tests demonstrated outstanding antibacterial effects combined with an absence of toxicity. Additionally, we found that the resulting polymers, unlike their nanoparticle counterparts, also exhibited strong antioxidant effects. In summary, we demonstrated the effectiveness of ultrasound in polymer chemistry and highlighted the importance of the sonochemical approach in the chemical modification of polysaccharides. This approach enables the synthesis of derivatives with improved physicochemical and biological properties. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
45. Bacterial Adhesion to Natural and Synthetic Fibre-Forming Polymers: Influence of Material Properties.
- Author
-
Čuk, Nina, Simončič, Barbara, Fink, Rok, and Tomšič, Brigita
- Subjects
- *
BACTERIAL adhesion , *SYNTHETIC textiles , *POISONS , *ANTIBACTERIAL agents , *FREE surfaces , *SURFACE charges - Abstract
Polymer-based textiles have a major impact on human well-being, as they provide the desired functional protection and aesthetic comfort when worn. However, natural and synthetic polymer-based textiles can also pose serious health risks, as they are surfaces that allow the adhesion of various bacteria, including pathogenic bacteria. To minimise these problems, antibacterial chemical treatments are generally applicable in the case of polymer-based textiles. However, to avoid the use of potentially toxic chemicals, sustainable approaches require the customised design of non-adhesive polymer-based textiles, considering their chemical, physicochemical, constructional, and textural properties. Before designing, several articles are required to gain sufficient knowledge of the described object. Despite the urgent need to combat bacteria (on polymer-based textiles), which pose a serious global health risk, only a few review articles have been published that address bacterial adhesion in the context of superhydrophobic and antibacterial textile materials, while only one review article holistically addresses the textile factors and their influence on this phenomenon. The aim of this review article is to expand the insufficient knowledge about bacterial adhesion to polymer-based textiles on the basis of theoretical findings and real examples through a high degree of structuring, simplification, holistic consideration, and visualization. Therefore, this review provides an insight into the mechanisms involved in bacterial adhesion and a comprehensive overview of the influence of different textile factors, such as chemical composition, hydrophilicity/hydrophobicity, surface charge, surface free energy, roughness, and porosity, on bacterial adhesion. To emphasise the importance of the synergistic effect of the combined textile factors, examples of the influence of hydrophilicity/hydrophobicity in combination with surface charge, surface roughness, and porosity are discussed. From the review, it can be concluded that the combination of hydrophilicity/hydrophobicity and the surface charge of textile fibres and bacteria is crucial for bacterial adhesion, with roughness and porosity being the most important factors among the constructive and textural properties of polymer-based textiles. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
46. Green synthesis of silver-titanium dioxide nanoparticles using chestnut extract for the preservation of leather artifacts.
- Author
-
Fan, Jia, Zhang, Mingrui, Liu, Jie, Lei, Yong, Kaya, Mǎdǎlina Georgiana Albu, and Tang, Keyong
- Subjects
- *
OXIDANT status , *CONGO red (Staining dye) , *BAND gaps , *ANTIBACTERIAL agents , *REDUCING agents - Abstract
• Novel synthesis method. Ag-TiO 2 NPs are synthesized using chestnut extract as both a template and a reducing agent. • Multifunctional properties. The synthesized Ag-TiO 2 NPs possess excellent UV shielding, self-cleaning capacity, antibacterial ability, and antioxidant capacity. • Effective leather artifact preservation. This effective preservation strategy ensures the long-term protection of leather artifacts, safeguarding the cultural significance for future generations. The deterioration of leather artifacts can be caused by exposure to light, pollutants, microbes, and oxidation. In this work, silver-titanium dioxide nanoparticles (Ag-TiO 2 NPs) were synthesized using chestnut extract as both a template and a reducing agent, providing UV light shielding, self-cleaning capacity, antibacterial activity, and antioxidant capacity. The results indicated that the addition of chestnut extract and Ag significantly enhanced the UV light shielding capability of Ag-TiO 2 NPs by enhancing the light absorption efficiency, as well as reduced the band gap from 3.20 eV to 2.82 eV, and improved the self-cleaning capability as evidenced by an increase in Congo red (CR) dye degradation rate from 26 % to 55 %. Additionally, Ag-TiO 2 NPs also exhibited remarkable antibacterial activity, as evidenced by a significant increase in the inhibition zone against bacteria, as well as enhanced antioxidant capability with the DPPH free radical scavenging capability increased from 22 % to 88 %. After Ag-TiO 2 NPs treatment, there was no obvious change in the appearance of leather, while the antibacterial activity of leather was significantly increased. The Ag-TiO 2 NPs produced through a green approach could offer robust UV light shielding, self-cleaning capacity, antibacterial activity, and antioxidant capacity to prevent the deterioration of leather artifacts, making a significant contribution to the long-term preservation of cultural heritage. The green synthesis of Ag-TiO 2 NPs using chestnut extract as both a template and a reducing agent was conducted, with excellent UV light shielding, self-cleaning capacity, antibacterial activity, and antioxidant capacity for the long-term preservation of leather artifacts. [Display omitted] [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
47. Antibacterial activity of Au(I), Pt(II), and Ir(III) biotin conjugates prepared by the iClick reaction: influence of the metal coordination sphere on the biological activity.
- Author
-
Moreth, Dominik, Stevens-Cullinane, Lars, Rees, Thomas W., Müller, Victoria V. L., Pasquier, Adrien, Song, Ok-Ryul, Warchal, Scott, Howell, Michael, Hess, Jeannine, and Schatzschneider, Ulrich
- Subjects
- *
ISOTHERMAL titration calorimetry , *TRANSITION metal complexes , *ENTEROCOCCUS faecium , *ANTIBACTERIAL agents , *CYTOTOXINS , *PLATINUM , *BENZENE derivatives - Abstract
A series of biotin-functionalized transition metal complexes was prepared by iClick reaction from the corresponding azido complexes with a novel alkyne-functionalized biotin derivative ([Au(triazolatoR,R′)(PPh3)], [Pt(dpb)(triazolatoR,R′)], [Pt(triazolatoR,R′)(terpy)]PF6, and [Ir(ppy)(triazolatoR,R′)(terpy)]PF6 with dpb = 1,3-di(2-pyridyl)benzene, ppy = 2-phenylpyridine, and terpy = 2,2′:6′,2′′-terpyridine and R = C6H5, R′ = biotin). The complexes were compared to reference compounds lacking the biotin moiety. The binding affinity toward avidin and streptavidin was evaluated with the HABA assay as well as isothermal titration calorimetry (ITC). All compounds exhibit the same binding stoichiometry of complex-to-avidin of 4:1, but the ITC results show that the octahedral Ir(III) compound exhibits a higher binding affinity than the square-planar Pt(II) complex. The antibacterial activity of the compounds was evaluated on a series of Gram-negative and Gram-positive bacterial strains. In particular, the neutral Au(I) and Pt(II) complexes showed significant antibacterial activity against Staphylococcus aureus and Enterococcus faecium at very low micromolar concentrations. The cytotoxicity against a range of eukaryotic cell lines was studied and revealed that the octahedral Ir(III) complex was non-toxic, while the square-planar Pt(II) and linear Au(I) complexes displayed non-selective micromolar activity. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
48. Isolation and Characterization of Bacteriocin Producing Levilactobacillus brevis Strain ABRIINW-K from Buffalo Dung.
- Author
-
Azam, Mohd, Srivastava, Rashi, and Ahmed, Tanzeel
- Subjects
- *
BASIC proteins , *LACTOBACILLUS brevis , *GRAM'S stain , *ANTIMICROBIAL peptides , *ANTIBACTERIAL agents - Abstract
Bacteriocins are proteins secreted by many species of bacteria to inhibit other bacteria, thus eliminating competitors to gain resources. Bacteria from the Lactobacillus group are known for their applications as probiotics and food preservatives. They have earned a reputation for producing substances that inhibit the growth of other microorganisms, which include organic acids, diacetyl, and bacteriocins. Produced by the ribosomes, bacteriocins are cationic proteins that inhibit other bacteria coexisting within a shared ecological habitat. Due to their potential uses in a variety of applications large-scale production of Bacteriocins would be necessary. The study aimed to identify and characterize Lactobacillus bacteria that produce potent bacteriocins and to analyze the antimicrobial activity and stability of the isolated bacteriocin under various physical and biochemical conditions. A total of 50 samples including buffalo dung, cheese, and rhizospheric region of plants were screened to isolate 8 Lactobacillus Li-1, Li-2, Li-3, Li-4, Li-5, Li-6, Li-7, and Li-8, confirmed by gram staining and other biochemical tests. The cell free supernatant from the Li-3 strain showed higher inhibition of Escherichia coli and Staphylococcus aureus, as compared to the other isolated strains. Li-3 strain was further identified as Levilactobacillus brevis strain ABRIINW-K by 16S rRNA gene sequencing. The bacteriocin isolated from this strain is a thermostable peptide (~6kDa), which is characteristic of class II bacteriocins, with potent antibacterial activity against Lactobacillus rhamnosus, Escherichia coli, and Salmonella enterica. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
49. Constituents and Antibacterial Activity of Essential Oil of Nyctanthes arbor-tristis Flower.
- Author
-
Sattar, Tayyaba, Intisar, Azeem, Kousar, Rehana, Ramzan, Arooj, Niazi, Abdul Rehman Khan, Qadir, Muhammad Abdul, Ahmed, Ejaz, Ferdosi, Malik Fiaz Hussain, and Abid, Muhammad Amin
- Subjects
- *
PHENYL compounds , *EXTRACTION techniques , *KLEBSIELLA pneumoniae , *ESSENTIAL oils , *ANTIBACTERIAL agents - Abstract
In this study, the composition and antibacterial activity of essential oil from the flower of Nyctanthes arbor-tristis were determined. The extraction was carried out utilizing the microwave-assisted extraction technique with a short extraction time of 60 min, yielding 0.342% (w/w). Separation and characterization were performed by gas chromatography-mass spectrometric analysis, identifying a total of 34 constituents, including major compounds: phenyl ethyl alcohol (26.1%), eucarvone (18.7%), furfural (10.7%), benzaldehyde (4.8%), phytol (4.7%), and methyl hexadecanoate (3.1%). In the next step, an agar disk diffusion assay was performed to assess the antimicrobial activity of the oil against four different bacterial strains, namely Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa, resulting in zones of inhibition measuring 9, 12, 11, and 9 mm, respectively. However, the broth macrodilution method was carried out against Staphylococcus aureus and Klebsiella pneumoniae, revealing minimum inhibitory concentrations of 2.5 and 5 mg/mL, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
50. Chemical constituents and bioactivities of the essential oils of Magnolia biondii flower buds from three provinces in China.
- Author
-
Li, Tian‐Xiao, Li, Li‐Peng, Zhang, Da‐Yuan, Zhao, Guo‐Liang, Liang, Yong‐Wei, Jia, Xue‐Wei, Guo, Lei, Xu, Chun‐Ping, and Gao, Xin
- Subjects
- *
ESSENTIAL oils , *HERBAL medicine , *ANTIBACTERIAL agents , *MAGNOLIAS , *MEDICINAL plants - Abstract
Magnolia biondii flower buds are a well‐known medicinal plant in China, and it is important to determine the differences in aroma, flavour components, and biological activity of the essential oils of M. biondii flower buds (EOM) from different origins. In this study, the essential oils of M. biondii flower buds from Sichuan (EOM‐SC), Anhui (EOM‐AH) and Henan (EOM‐HN) provinces were extracted by hydrodistillation. The condition of the extraction process was optimized. The differences in the flavour compounds were further confirmed by GC–MS and relative odour activity value (ROAV) analyses. In addition, the antibacterial and antioxidant activity was also evaluated. The results showed that the optimized condition for steam distillation was water: flower powder ratio = 10:1 with extraction time for more than 3.0 h. Interestingly, special floral, fruity and freshness flavours were found for EOM‐SC, and the medicinal herb and sweetness odours of EOM‐HN were more prominent. The numbers and contents of flavour compounds in EOM‐SC and EOM‐HN were higher than those of EOM‐AH. Eucalyptol, β‐pinene, linalool, α‐terpineol and sabinene could be proposed as the key mutual flavour compounds for three essential oils. In addition, the strong floral, fruity and freshness aroma of EOM‐SC could be associated with the high ROAVs of α‐terpineol, linalool and sabinene. Moreover, EOM‐SC exhibited better antibacterial and antioxidant activity than those of the other two essential oils. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.