Potent Antibacterial Activity Research Articles

Valorization of oil refinery by-products: production of sophorolipids utilizing fatty acid distillates and their potential antibacterial, anti-biofilm, and antifungal activities.

Starmerella bombicola is a native yeast strain producing sophorolipids as secondary metabolites. This study explores the production, characterization, and biological activities of sophorolipids and investigates the antimicrobial, anti-biofilm, and antifungal properties of sophorolipids produced from oil refinery wastes by the yeast Starmerella bombicola. The present work demonstrated that S. bombicola MTCC 1910 when grown in oil refinery wastes namely palm fatty acid distillates and soy fatty acid distillates enhanced the rate of sophorolipids production drastically in comparison to vegetable oil, sunflower oil used as hydrophobic feedstock. Sophorolipid yields were 18.14, 37.21, and 46.1g/L with sunflower oil, palm, and soy fatty acid distillates respectively. The crude biosurfactants were characterized using TLC, FTIR, and HPLC revealing to be acetylated sophorolipids containing both the acidic and lactonic isomeric forms. The surface lowering and emulsifying properties of the sophorolipids from refinery wastes were significantly higher than the sunflower oil-derived sophorolipids. Also, all the sophorolipids exhibited strong antibacterial properties (minimum inhibitory concentrations were between 50 and 200µgmL-1) against Salmonella typhimurium, Bacillus cereus, and Staphylococcus epidermidis and were validated with morphological analysis by Scanning electron microscopy. All the sophorolipids were potent biofilm inhibitors and eradicators (minimum biofilm inhibitory and eradication concentrations were between12.5to1000µgmL-1) for all the tested organisms. Furthermore, antifungal activities were also found to exhibit about 16-56% inhibition at 1mgmL-1 for fungal mycelial growth. Therefore, this endeavour of sophorolipids production using palm and soy fatty acid distillates not only opens up a window for the bioconversion of industrial wastes into productive biosurfactants but also concludes that sophorolipids from oil refinery wastes are potent antimicrobial, anti-biofilm, and antifungal agents, highlighting their potential in biotechnological and medical applications.

Antimicrobial Isochroman-Derived Atropo-diastereomeric Dimers from Penicillium steckii SCISO 41228.

A pair of unidentified atropisomeric dimers, penicisteckins G (1) and H (2), and twelve known compounds (3-16) were isolated from the marine coral-derived fungus Penicillium steckii SCISO41228. Their structures including the absolute configuration were determined by HR-ESI-MS, ECD, 1D-, and 2D-NMR spectra. Compounds 1 and 2 exhibited potent antibacterial activity against most pathogenic strains, especially for MASA and Micrococcus luteus, with MIC values of 4.0 μg·mL-1. In addition, compounds 2 and 3 exhibit potent antioxidant activity with IC50 values of 10.76 and 8.66 μg·mL-1, respectively.

Biodiversity and Bioprospecting of Fungal Endophytes from Houttuynia cordata Thunb. as a Potential Antibacterial and Anticancer Agent.

Endophytic fungi are considered a new source of bioactive compounds that have important applications in agriculture and medicine. This study aims to investigate the biodiversity and potential of endophytic fungi isolated from Houttuynia cordata Thunb. as antimicrobials and anticancer agents. Out of ten isolated endophytes, four species have never been reported to be associated with H. cordata: Ceratobasidium sp., Cladosporium sp., Phomopsis sp., and Fusarium sp. The antibacterial activity assay revealed that the ethyl acetate extract of Ceratobasidium sp. HCS-3 possessed most potent antibacterial activity against Escherichia coli and Staphylococcus aureus. In addition, its cytotoxic activity test showed the promising anticancer activity on lung cancer A549, osteosarcoma MG-63, and cervical cancer HeLa cells with IC50 of 4.55 ±1.16, 32.14 ±2.78, and 1.54 ±0.66 ppm, respectively. Furthermore, metabolite profiling identified 66 compounds suggesting that benzoic acid, farnesol, and cyclopeptides may contribute to the antibacterial activity, while 4-methoxycinnamic acid may have anticancer potential.

Identification of antibacterial constituents from Rhododendron simsii Planch with an activity-guided method

Bacterial infections and antibiotic resistance pose significant public health challenges globally. Natural products serve as valuable sources for discovering antimicrobial agents. Rhododendron simsii Planch, a folk medicine, is traditionally used to treat various inflammatory diseases. In this study, we investigated the antibacterial metabolites derived from R. simsii Planch. Rhodosimsiin A (1), bearing a 1,5-seco-1,6 and 3,6-epoxy grayanane diterpene skeleton, representing a novel 5/6/7/6/5 pentacyclic ring system, and 3β,16α-dihydroxy-6β-ethoxy-14β-acetoxy-grayan-1(5)-ene-10-one (4), which represents the first example of the degradation of C-20 and carbonylation in C-10 diterpenoid, together with two new grayanane diterpenes (2−3), three new triterpenes (13−15), and known analogs (5−12, 16−30), were isolated from the leaves of R. simsii Planch by using the bioassay-guided method. Their structures were elucidated by comprehensive spectroscopic analyses, and absolute configurations were established by single-crystal X-ray diffraction and calculated ECD spectra. Compounds 14, 15, 18, 20, 27, 28, and 30 exhibited potent antibacterial activity with an MIC50 of 1.4–24.3 μg/mL against Staphylococcus aureus. The findings of this research indicate that secondary metabolites derived from R. simsii Planch are promising natural antimicrobial candidates.

Synthesis of New Imidazolo‐Benzenesulfonamide Linked 1,2,3‐Triazoles as Potent Antibacterial and Antibiofilm Agents

AbstractIn search of better antibacterial and antibiofilm agents, this report presents a series of novel 1,2,3‐triazole‐imidazole‐benzenesulfonamide derivatives that were synthesized and evaluated for their antibacterial and antibiofilm activity in vitro. Antibacterial activity against three Gram‐positive bacterial strains, B. subtilis, S. aureus, and S. epidermidis, was evaluated. Among all the tested compounds, 4‐methyl‐N‐(1‐methyl‐1H‐imidazol‐2‐yl)‐N‐((1‐(4‐(trifluoromethyl)phenyl)‐1H‐1,2,3‐triazol‐4‐yl)methyl)benzenesulfonamide and N‐((1‐(3,5‐difluorophenyl)‐1H‐1,2,3‐triazol‐4‐yl)methyl)‐4‐methyl‐N‐(1‐methyl‐1H‐imidazol‐2‐yl)benzenesulfonamide exhibited potent antibacterial activity against S. aureus and B. subtilis bacterial strains. Biofilm profiles for the potent compounds and it was observed from the results that the above two active compounds displayed promising biofilm inhibition against B. subtilis and S. aureus, with MIC values ranging between 2.19 ± 0.37 and 3.38 ± 0.35 µg/mL. Furthermore, potent compounds screened for their in silico molecular docking studies against penicillin‐binding protein and compound N‐((1‐(3,5‐dichlorophenyl)‐1H‐1,2,3‐triazol‐4‐yl)methyl)‐4‐methyl‐N‐(1‐methyl‐1H‐imidazol‐2‐yl)benzenesulfonamide show highest binding energy as compared to the standard and remaining compounds.

Bioconjugation of Serratiopeptidase with Titanium Oxide Nanoparticles: Improving Stability and Antibacterial Properties

Antimicrobial resistance (AMR) poses a significant global health threat, necessitating the development of novel antibacterial strategies. Serratiopeptidase (SP), a metalloprotease produced by bacteria such as Serratia marcescens, has gained attention not only for its anti-inflammatory properties but also for its potential antibacterial activity. However, its protein nature makes it susceptible to pH changes and self-proteolysis, limiting its effectiveness. This study aimed to increase both the enzymatic stability and antibacterial activity of serratiopeptidase through immobilization on titanium oxide nanoparticles (TiO2-NPs), leveraging the biocompatibility and stability of these nanomaterials. Commercial TiO2-NPs were characterized using TGA/DTG, FT-IR, UV–Vis, and XRD analyses, and their biocompatibility was assessed through cytotoxicity studies. Serratiopeptidase was produced via fermentation using the C8 isolate of Serratia marcescens obtained from the intestine of Bombyx mori L., purified chromatographically, and immobilized on carboxylated nanoparticles via EDC/NHS coupling at various pH conditions. The optimal enzymatic activity was achieved by using pH 5.1 for nanoparticle activation and pH 5.5 for enzyme coupling. The resulting bioconjugate demonstrated stable proteolytic activity at 25 °C for 48 h. Immobilization was confirmed by FT-IR spectroscopy, and the Michaelis–Menten kinetics were determined. Notably, the bioconjugate exhibited two-fold greater antibacterial activity against E. coli than the free enzyme or TiO2-NPs at 1000 µg/mL. This study successfully developed a serratiopeptidase–TiO2 bioconjugate with enhanced enzymatic stability and antibacterial properties. The improved antibacterial activity of the immobilized enzyme presents a promising approach for developing new tools to combat antimicrobial resistance, with potential applications in healthcare, food safety, and environmental protection.

Impact of plasmonic silver on the perovskite Bi9Ti6FeO27: Removal of tetracycline and antimicrobial activity

The synthesis, characterization, photocatalytic, and antibacterial analysis of plasmonic Ag- loaded Bi9Ti6FeO27 at various concentrations of Ag are presented in this study. The synthesis of Ag/Bi9Ti6FeO27 is based on the impregnation of different weight percentages of Ag (20, 50, and 80) on Bi9Ti6FeO27. The XRD and HRTEM result shows that the perovskite Bi9Ti6FeO27 maintained orthorhombic crystallinity having space group Pnm (No.62). Upon addition of Ag, do not disturb the crystallinity of Bi9Ti6FeO27. XPS analysis displays the valence states and surface chemical composition of the as-prepared Ag/Bi9Ti6FeO27. All the composites exhibit good UV–visible absorbance in the range of 200–800 nm, and the band-gap energy gradually decreases from 3.30 eV to 2.73 eV with an increase in silver content. The photocatalytic degradation of 40 ppm tetracycline is examined at 120 min at neutral pH (7). Loading of Ag on Bi9Ti6FeO27 significantly promoted the photocatalytic degradation efficiency of tetracycline (84 %). Furthermore, the antibacterial activity of Ag/Bi9Ti6FeO27 was investigated against “Escherichia coli”, Klebsiella pneumoniae”, and “Acinetobacter baumannii” bacteria. Higher loading of Ag on Bi9Ti6FeO27 exhibited the most potent antibacterial activity by effectively inhibiting the growth of both bacterial strains through reactive oxidative species and the presence of silver nanoparticles. The composite has proved its stability through the five repeated cycles. This work provides an emerging strategy to finely design the nanocomposites and highlight their potential for environmental remediation and healthcare industries.

An in-depth exploration of ethnomedicinal applications, phytochemical profiles, and pharmacological potentials: unveiling Withania somnifera

Researchers have extensively studied Withania somnifera (L.) Dunal, a woody shrub renowned for its multifaceted medicinal attributes such as antibacterial, anti-inflammatory, adaptogenic, aphrodisiac, and tonifying properties, because of its medicinal and traditional values. However, comprehensive information about its medicinal uses and pharmacological implications is scattered across various sources. Thus, this study aims to provide a comprehensive review of its ethnomedicinal uses, phytochemistry, and pharmacological attributes, consolidating information from diverse data sources. Systematic investigations have revealed the presence of diverse phytochemicals in W. somnifera, including major alkaloids, withanolides, flavonoids, tannins, oils, phytosterols, and amino acids. Extracts, fractions, and bioactive compounds derived from W. somnifera exhibited potent antibacterial, anti-inflammatory, anti-aging, anti-analgesic, anti-cancer, antivenom, anti-fungal, and anti-viral activities. W. somnifera serves as a valuable source of phytochemicals with diverse biological activities, offering significant therapeutic benefits globally. However, further studies are needed to assess potential side effects. Additionally, while several isolated compounds have demonstrated notable bioactivities, future research should focus on elucidating their mechanistic features to facilitate their integration into drug discovery endeavors.

LC-MS-based metabolomics for the profiling of bioactive compounds in tree peony flower buds with multiple bioactive potentials

Tree peonies (Paeonia suffruticosa) are important pharmaceutical and oilseed crops widely cultivated in China. Tree peony flowers, as important by-products of the industrial crops, are conventionally used as folk medicine with health-promoting effects on human. However, the in-depth understanding of biologically active compounds in tree peony flowers is scarce. In this study, an in-depth analysis of bioactive compounds in tree peony flower buds (TPFBs) from 74 cultivars was conducted using an integrated LC-MS-based metabolomic approach. Ninety-two metabolites were tentatively identified in TPFBs. The quantitative results revealed that TPFBs were abundant in bioactive compounds. Among these, paeoniflorin, albiflorin, cynaroside, and pentagalloylglucose (PGG) emerged as the primary chemical markers of TPFBs, showing significant variations based on genotype. Each extract of TPFB exhibited potent antioxidant, antibacterial, and anti-neuroinflammatory activities. Notably, TPFB extract showed the highest effectiveness in inhibiting L. monocytogenes among all tested bacteria. Cynaroside was predicted to serve as a pivotal component in TPFB for its anti-neuroinflammatory effects by interacting with toll-like receptor 4 (TRL4) and interleukin-1beta (IL-1β). This study offers novel insights into the bioactive compounds and bioactivities of TPFBs, which lays theoretical basis for the application in pharmaceutical industry.

Anchoring atomic Pd on molybdenum disulfide with state-of-the-art specific activity in the electrochemical dehalogenation of florfenicol

The widespread discharge of halogenated organic pollutants (HOPs) in wastewater brings significant risks to the environment and human health due to potent high toxicity, antibacterial activity, and strong biodegradation resistance. Adsorbed atomic hydrogen (H*ads)-mediated electrocatalytic hydrodehalogenation (EHDH) has been recognized as an efficient strategy for HOPs removal through selectively breaking carbon-halogen bonds. In this work atomic Pd uniformly anchored on molybdenum disulfide (denoted as Pd-MoS2) was synthesized through a facile hydrothermal method and found with state-of-the-art specific activity in florfenicol (FLO) removal via the H*ads-mediated EHDH process. Pd-MoS2 completely dehalogenated (∼100 %) FLO within 30 min at a rate constant of 0.15 min−1, which was 6.0, 6.5 and 33.1 times the value of MoS2, Pd/C and carbon paper samples, respectively. Notably, the toxicity of the wastewater was reduced to 1/6 of its original value after the treatment. Moreover, Pd-MoS2 presented superior catalytic stability in five successive cycles. Furthermore, Pd-MoS2 was also robust in complex water environment with practical applicability for industrial wastewater treatment. A dual-active-center mechanism with enhanced H*ads production capacity and the improved H*ads utilization efficiency was contributed to the increased EHDH activity on Pd-MoS2.

New Schiff Base Derived Organotin (IV) Complexes: Synthesis, Characterization, In vitro and In silico Biological Studies

Aims: The creation and testing of new Schiff base-based antibacterial organotin (IV) complexes were the objectives of this investigation. Background: Due to developed resistance, antibiotics that were once often used to treat microor-ganisms are no longer effective against them. It is thought that organotin compounds synthesized from Schiff bases have significant pharmacological effectiveness and work well as antibacterial agents. Methods: Thiocarbohydrazide and dehydroacetic acid were condensed to create the Schiff base, followed by processing with dialkyltin(IV)dichloride to synthesize the final product. Modern an-alytical techniques were used to clarify the compounds' probable structural details. The crystalline nature of the produced compounds was tested using PXRD. Results: All of the compounds were thermally stable up to 300°C. All of the synthesized com-plexes showed potent antibacterial activity in the range of 250 to 400 μg/ml. Furthermore, the computational biology research showed that, in contrast to ligands, which had a binding energy of -7.3 to -7.4 kcal/mol, complexes interacted well with dihydropteroate synthase and DNA gy-rase. Conclusion: The current study offered a unique technique for synthesizing diorganotin(IV) de-rivatives of N-substituted Schiff bases that are physiologically active. The results show that the chemicals created are promising antibacterial mediators against diseases that affect humans in the modern world. It might also open the door to future studies on drug-resistant microorganisms that could have biological uses.

Innovative synthesis and molecular modeling of actinomycetes-derived silver nanoparticles for biomedical applications

The rising demand for innovative antimicrobial solutions has shifted focus towards silver nanoparticles (AgNPs), especially those produced through eco-friendly methods. This study introduces a novel approach utilizing actinomycetes strains—Streptomyces albus, Micromonospora maris, and Arthrobacter crystallopoietes—to biosynthesize AgNPs with remarkable antibacterial properties. Through molecular characterization, we identified unique features of these nanoparticles, and computational modeling suggested significant ion-ligand interactions with proteins 6REV and 3K07. Our research highlights the promise of these biogenically synthesized nanoparticles in advancing biomedical applications. Actinomycetes were sourced and screened for their ability to produce metallic nanoparticles, revealing that among 35 samples, only six showed this capability. Notably, Streptomyces albus strain smmdk14 (OR685674), Micromonospora maris strain smmdk13 (OR685672), and Arthrobacter crystallopoietes strain smmdk12 (OR685674) were identified as effective silver nanoparticle producers. The synthesized nanoparticles demonstrated potent antibacterial activity against common pathogens including E. coli, Pseudomonas aeruginosa, Klebsiella spp., Enterococcus faecalis, Staphylococcus aureus, and Acinetobacter spp. The data obtained from color change observation, UV–visible spectrophotometry, Zeta potential, FTIR spectroscopy, and transmission electron microscopy (TEM) characterized AgNPs potentiality. The nanoparticles were spherical, with sizes ranging from 6.46 nm to 24.7 nm. Optimization of production conditions, comparison of antimicrobial effects with antibiotics, evaluation of potential toxicity, and assessment of wound-healing capabilities were also conducted. The biosynthesized AgNPs exhibited superior antibacterial properties compared to traditional antibiotics and significantly accelerated wound healing by approximately 66.4 % in fibroblast cell cultures. Additionally, computational analysis predicted interactions between various metal ions and specific amino acid residues in proteins 6REV and 3K07. Overall, this study demonstrates the successful creation of AgNPs with notable antibacterial and wound-healing properties, underscoring their potential for medical applications.

Two novel antimicrobial peptides P33-57 and mP168-187 from zebrafish showing potent antibacterial activities

It is known that overuse or abuse of antibiotics has undoubtedly accelerated the global antibiotic resistance crisis, and long-time use of antibiotics may have adverse effects on the health of animal, human, and ecosystem. Therefore, it is necessary to find antibiotic alternatives that can be used in aquaculture and are non-toxic to the human. Here we clearly demonstrated that both the PH and FYVE domain of Plekhf2 in zebrafish have antibacterial properties and can interact with PGN in this study. Therefore, we screened four candidate peptides from the two domains. It was demonstrated that P152-172 and P168-187 had no obvious antibacterial activities, while P33-57 and mP168-187 had strong antibacterial activities, which may be used as antimicrobial peptides. Additionally, transmission electron microscopy experiment revealed that P33-57 and mP168-187 can destroy the cell wall of bacteria, thereby directly killing bacteria. Importantly, it was found that P33-57 and mP168-187 had no hemolysis to red blood cells and lacked cytotoxicity. In summary, P33-57 and mP168-187could be seen as antibacterial activity centers of PLEKHF2 and may be promising antimicrobial peptides to combat bacterial infections facing an antibiotic-resistance crisis.

Multi-omics revealed antibacterial mechanisms of licochalcone A against MRSA and its antimicrobic potential on pork meat

Licorice flavonoids (LFs) exhibit potent antibacterial activities against Gram-positive bacteria. However, the related mechanism remains unclear. This study aims to illustrate the mechanisms of licochalcone A (LA), a main flavonoid in LFs, against methicillin-resistant Staphylococcus aureus (MRSA). The anti-MRSA effect of LA was comprehensively investigated by a combination of proteomics and metabolomics studies. Meanwhile, LA was loaded in glycyrrhizin (GA) micelles (GA@LA micelles) to improve its water solubility. The results demonstrated that LA could disrupt the arginine metabolism and cause the accumulation of intracellular ROS in MRSA. In addition, LA could inhibit the expression of glucokinase in MRSA, which affect the synthesis of ATP, fatty acids, and peptidoglycan. GA@LA micelles have the latent ability to inhibit the growth of MRSA on fresh pork.

Polydopamine-based surface coating fabrication on titanium implant by combining a photothermal agent and TiO2 nanosheets for efficient photothermal antibacterial therapy and promoted osteogenic activity

Developing titanium-based dental implants with both excellent antibacterial properties and good osseointegration is crucial for the success of the implant operation and the long-term durability of the implant. In this study, a polydopamine-based coating was created by attaching TiO2 nanosheets-cyanine composites onto the titanium surface, enabling the integration of effective photothermal antibacterial therapy with osseointegration. The exceptional dual-photothermal conversion abilities of polydopamine and cyanine in the coating resulted in outstanding photothermal antibacterial and antibiofilm therapy against four types of bacteria. Furthermore, TiO2 nanosheets promoted the adhesion, proliferation and early osteogenic differentiation of osteoblasts. In an infected dental implant model in rats, the developed coating exhibited potent antibacterial activity and remarkable osteogenic differentiation in the bone, leading to increased bone formation around the implants. This innovative approach, combining photothermal therapy with osteogenic two-dimensional nanomaterials, presents a novel method for surface functionalization of implants to achieve effective antibacterial and osseointegration capabilities.

The enhanced antibacterial and antibiofilm properties of titanium dioxide nanoparticles biosynthesized by multidrug-resistant Pseudomonas aeruginosa

AbstractThe emergence of Multidrug-resistant (MDR) bacteria are becoming a major worldwide health concern, encouraging the development effective alternatives to conventional antibiotics. The study identified P. aeruginosa and assessed its antimicrobial sensitivity using the Vitek-2 system. Carbapenem-resistant genes were detected through Polymerase chain reaction (PCR). MDR- P. aeruginosa isolates were used to biosynthesize titanium dioxide nanoparticles (TiO2NPs) and characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM). A study involving 78 P. aeruginosa isolates revealed that 85.8% were MDR, with meropenem and amikacin showing effectiveness against 70% of the isolates. The most prevalent carbapenemase gene was blaOXA-48, present in 83% of the isolates. Majority of the isolates formed biofilms, and biosynthesized TiO2NPs were able to reduce biofilm formation by 94%. TiO2NPs exhibited potent antibacterial action against MDR-Gram-negative bacilli pathogens and showed synergistic activity with antibiotics, particularly piperacillin, with a significant fold increase in areas (283%). A new local strain of P. aeruginosa, identified as ON678251 in the World GenBank, was found capable of producing TiO2NPs. Our findings demonstrate the potential of biosynthesized TiO2NPs to manage antibiotic resistance and regulate the formation of biofilms. This presents a promising direction for the creation of novel antimicrobial agents or substitutes for use in clinical settings, particularly in the management of isolates capable of resisting multiple drugs.

Green Synthesis of Silver Nanoparticles with Bioreductant from Lime Juice Powder (<i>Citrus aurantifolia</i>): Effect of Concentration and pH

Significant development in antibacterial agents derived from metal nanoparticles is currently underway. One commonly employed type is silver nanoparticles (AgNPs), which display potential antibacterial activity at lower concentrations compared to other metals. Due to their high surface-to-volume ratio and small size, AgNPs can readily penetrate bacterial cell walls. Green synthesis methods of AgNPs, such as utilizing plants as reducing agents, offer substantial advantages over other synthesis techniques. Lime (Citrus aurantifolia), containing compounds like flavonoids and saponins, can serve as a natural reducing agent, converting Ag+ ions to Ag0. This study aims to evaluate the effects of AgNO3 concentration, lime juice powder concentration, and pH on the formation and characteristics of AgNPs, as well as their activity against the bacteria Propionibacterium acnes, Staphylococcus aureus, and Escherichia coli. Results indicate that at an AgNO3 concentration of 1 mM, lime juice extract at 1% with a pH of 9 produces optimal AgNP formation, with an absorbance of 4.631 and particle size of 68.4 nm. AgNPs exhibit higher antibacterial activity than AgNO3. AgNPs synthesized with lime juice powder can increase their activity and have the advantages of being safe and environmentally friendly since they use plant material as a reducing agent.

Comparison of piperine content, antimicrobial and antioxidant activity of Piper chaba root and stem

Piper chaba (locally known as “Choi Jhal”) is used traditionally as spices and folk medicine in different parts of Bangladesh. One of the most important bioactive compounds in this plant is piperine. In this study, the amount of piperine in P. chaba root and stem was investigated and the optimal solvent for piperine extraction at room temperature was also studied. High performance liquid chromatography (HPLC) was operated using a reverse phase column where methanol and water (70:30) were used as mobile phase. The detection was performed using photo diode array (PID) detector at a wavelength of 345 nm. The standard piperine showed linearity between 0.005 % and 0.04 % and the correlation co-efficient found for the linearity was 0.9933. The percentage of relative standard deviation (RSD) for both retention time and peak area were less than 2.0 %. The theoretical plate number (N) > 3000 and a tailing factor (T) < 1.5 were found in the acceptable range. The recovery percentage (%) of standard piperine was 99.16 %. Low value of co-efficient of variation and standard deviation are recognized for high precision of the method. The highest amount of piperine was found in root extracted with methanol (MR) amounting to 1.75 % in the root powder. The maximum amount of piperine in the stem was 1.59 % when extracted with methanol (MS). The piperine quantification in other extract like n-hexane root (HR), ethyl acetate root (ER), n-hexane stem (HS), ethyl acetate stem (ES) were 0.76 %, 1.69 %, 0.33 % and 1.46 % respectively. Methanol has given the highest yield of piperine compared to ethyl acetate and n-hexane for both root and stem. The developed method was simple, rapid, economic and validated in terms precision, accuracy and recovery. This selective method is found to be repeatable, accurate and successfully utilized for the Piper extract in marketed and pharmaceutical samples with well chromatographic conditions. The ethyl acetate extract of root and stem showed promising DPPH (1, 1-diphenyl-2-picrylhydrazyl) free radical scavenging activity with an IC50 value of 39.62 ± 0.95 μg/mL and 43.85 ± 1.50 μg/mL respectively. The study reports potential antibacterial activity and antifungal activity of P. chaba root and stem extracts. These outcomes revealed that different extracts of P. chaba may be used as natural preservatives.

Green synthesis of ZnO/Fe3O4 nanoparticles with nigella sativa extract: Efficient degradation of methylene blue and antimicrobial properties

Zinc oxide (ZnO), iron oxide (Fe3O4) NPs, and ZnO/Fe3O4 nanocomposites (NCs) were synthesized using Nigella sativa (NS) seed extracts. These nanomaterials (NMs) were characterized by multiple analytical techniques like UV-visible spectrophotometers, FTIR spectroscopy, SEM, and XRD spectroscopy. The UV-visible spectrum showed 364 nm, 330 nm, and 331nm for ZnO NPs, Fe3O4 NPs, and ZnO/Fe3O4 NCs, respectively. Moreover, it was confirmed when the samples were run through FTIR techniques, and it was observed that the availability of bioactive functional groups was involved in the decline of bulk compounds to NPs. XRD showed their average nanoparticle size based on applying the formula of full width at half maximum (FWHM) for ZnO NPs, Fe3O4 NPs, and ZnO/Fe3O4 NCs at 29.52 nm, 22.08 nm, and 12.82 nm, respectively. In this study, the reduction of Methylene Blue (MB) dye was done by NPs and NCs, and their catalytic activities were investigated by a UV-visible spectrophotometer. MB dye showed the maximum absorption peak at 664 nm, and the reaction of MB was reduced using synthesized products with an accompanying color change reaction from blue to colorless within 60 min at 84%, 86%, and 99.5% degradation for ZnO NPs, Fe3O4 NPs, and ZnO/Fe3O4 NCs with rate constants of 0.00035, 0.00065, and 0.0015 Lmol-1S-1. The 2nd order rate constant was observed in this study. The agar disc diffusion method was used to investigate the potential antibacterial activity of synthesized NPs and NCs. This study is best suited for Gram-positive bacteria. NS seed extract-based synthesis of NCs could be an excellent catalyst and biological application for environmental pollution.

Antimicrobial Effects of Orthodontic Molar Tube Coated with ZnO Nanoparticles Using Electrophoretic Deposition Method: A Randomized Clinical Trial.

This study aimed to evaluate the antimicrobial effect of coated orthodontic molar tubes (COMT) with zinc oxide nanoparticles (ZnO NPs) using an electrophoretic deposition method (EPD) and to evaluate the orthodontic molar tubes (OMT) bond failure rate. Seventy-two orthodontic molar tubes (OMTs) for second molars were divided into two groups 36 each; one group coated with ZnO NPs and the other control negative uncoated. The OMT was coated using the EPD method with ZnO NPs in a concentration of 10g/l. The OMTs were randomly allocated using a split-mouth, cross-quadrant design. After 2weeks of appliance placement, swabs were taken from the surface of the OMTs for microbial assessment against Streptococcus mutans, Lactobacillus acidophilus, and total bacterial counts; additionally, plaque and gingival indices were assessed. The patient was followed for 3months to evaluate the bond failure rate. The COMT showed a statistically significant reduction in total bacterial accounts, S. mutans, and L. acidophilus compared to UOMT (P < 0.001). Furthermore, the plaque and gingival indices near COMT were significantly less than that of UOMT. The bond failure rate was not significant between the COMT and UOMT. The COMT with ZnO NPs has potent antibacterial activity against the tested pathogens with a reduction in the amount of plaque accumulation. The use of the EPD method was feasible without adverse effects on theorthodontic molar tubes bond failure rate.