Clear Zone Of Inhibition Research Articles

Exploring The in vitro Efficacy of Psidium Guajava Leaf Oil Against Cutibacterium Granulosum

One potential approach to treat acne vulgaris is by utilizing Cutibacterium granulosum (C. granulosum) to break down the biofilm formed by Cutibacterium acnes (C. acnes). When using cosmeceutical products containing certain essential oils, as they may have the unintended effect of eliminating C. granulosum, leading to the potential development of more severe acne vulgaris in the long term. No data for Psidium guajava (guava) leaves oil against C. granulosum has been reported. Therefore, this study aimed to investigate in vitro antimicrobial activity of guava leaves oil against C. granulosum. This oil was extracted from the guava leaves by hydrodistillation using a clevenger-type apparatus. Then, the chemical compositions of this crude oil were identified by gas chromatography-mass spectrometry. The percentage yield of this essential oil was 0.13 ± 0.2% (w/w) on fresh weight basis. The major compounds were β-caryophyllene (25.50%), limonene (11.58%), caryophyllene oxide (3.43%),a-copaene (2.92%), 1,8-cineole (2.08%), and a-pinene (1.28%). This essential oil exerted a potent antioxidant capacity with the half maximal inhibitory concentration of 32.7 ± 0.3 mg/ml from 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Additionally, the essential oil of guava leaves showed the susceptibility of C. granulosum by agar disc diffusion method with 22 ± 0.2 mm of clear inhibition zone. This essential oil also possessed against C. granulosum with the minimum inhibitory concentration (MIC) and minimum bacterial concentration (MBC) of 3.125 µg/ml and 6.25 µg/ml from the broth microdilution susceptibility test. From these findings, this essential oil exhibited notable synergistic antioxidant and antimicrobial activities against C. granulosum.

A comprehensive review of phytochemistry and antibacterial action of Tectona grandis

Tectona grandis L. (Teak) is one of the commercial plants which is often used in Southeast Asia. Globally, the total area of planted teaks reaches 3 million hectares, with about 31% of the land located in Indonesia. Preliminary phytochemistry showed bioactive constituents as alkaloids, tannins, flavonoids and phenolic compounds. Isolation and characterization by several methods were reported for quantifying the secondary metabolites found in the various parts of Tectona G, following the ICH guidelines and the following were reported, viz; Protocatechuic acid, Quinic acid, and its derivatives, Apigenin 7-O-diglucuronide, Luteolin, Luteolin 7-Odiglucuronide, Luteolin glucuronide, Diglucuronide, Apigenin glucuronide etc, which are responsible for their antibacterial action. The extractives of Tectona grandis were studied for antibacterial activities by agar well diffusion and disc diffusion method respectively. The test organism were isolates of nutrient broth, hospital strains, decayed food and Mueller Hinton Broth (MHB), antibacterial action of Tectona G were lucid as the extractives showed a maximum inhibitory effect; inhibition zone, evident by a clear zone of inhibition around the discs, minimum inhibitory concentration (MIC) and minimum bacteriocidal concentration (MBC) respectively. Accordingly, this review demonstrates the importance of the herbal plant (Tectona grandis) in the treatment of bacteria thus, preventing its resistance.

Rational strategy for construction of multifunctional coatings for achieving high fire safety, antibacterial, UV protection and electrical conductivity functions of textile fabrics

Sustainable and innovative multifunctional organic coatings were designed and developed for integrating effective flame retardancy, ultraviolet (UV) radiation protection, electrical conductivity and antibacterial functions to viscose textiles. The coatings-based nanocomposites were prepared from cellulose nanocrystal phosphate derived from waste cotton clothes, graphene sheets derived from mandarin shell, polyaniline nanofibers and polypyrrole (PPy) and elucidated using microscopic and spectroscopic tools. The nanomaterials-based coatings were first synthesized individually from their sustainable precursors and then utilized in nanocoatings fabrication. Variety of nanocoatings were developed from different combinations of nanofillers and mass ratios and then coated on viscose textile fabrics. The flammability, thermal stability, UV protection, electrical conductivity and antibacterial properties of the treated textile fabrics were studied and optimized. The flame retardancy properties of the developed textile fabrics were significantly improved achieving zero rate of burning compared to 193 mm/min for uncoated fabrics. This outstanding fire safety was ascribed to synergistic flame retardancy effect of coating layer based phosphorylated cellulose nanocrystals, graphene sheets and polyaniline nanofibers affording protective char barrier. The flame retardancy action was further elucidated using scanning electron microscopy (SEM) and Raman spectroscopy of protective char layer developed. Moreover, the coated fabrics affords excellent UV protection properties achieving ultraviolet protection factor (UPF) value of 90 compared to 2.7 for uncoated one. Additionally, new electrical conductivity feature was incorporated to the developed fabrics achieving reduction in electrical resistivity by 10,000 time affording conductive fabrics with convenient dissipation factor. Interestingly, the fabricated nanocoating integrates superior antibacterial properties against different bacteria strains Staphylococcus aureus (Gram-positive) and E-coli (Gram-negative) achieving clear antibacterial inhibition zone of 14.5 and 18.4 mm compared to zero mm inhibition for untreated one respectively. Furthermore, the influence of different nanocoatings on tensile strength properties of coated fabrics was studied and optimized.

TEMPORAL EFFICACY AND STERILITY TESTING OF POVIDONE-IODINE FROM AN OPEN BOTTLE.

To investigate the temporal efficacy and sterility of povidone-iodine (PI) against bacteria associated with postinjection endophthalmitis in an in vitro study. A single PI bottle was opened and tested for sterility and antibacterial efficacy. Povidone-iodine from the open bottle was inoculated onto a blood agar plate and evaluated for growth 24 hours later to test sterility; this was repeated for five consecutive days. To test for antibacterial efficacy, PI was instilled onto the surface of plates of Staphylococcus , Streptococcus , Enterococcus , Pseudomonas , and Haemophilus species. The plates were then evaluated 24 hours later for a clear zone of inhibition (i.e., no growth) where the PI was placed. This process was repeated for five consecutive days. Sterility testing showed no growth of organisms on the blood agar plates for each of the five days of testing. For antibacterial efficacy testing, zones of inhibition of growth were seen on each plate of bacterial colonies only where PI was placed, for each of the five days of testing. In this study, PI from an open bottle maintained its sterility and antibacterial efficacy for five days. These data could help support repeated use of the same bottle, reducing waste and costs for retina practices.

Controlled Size Oils Based Green Fabrication of Silver Nanoparticles for Photocatalytic and Antimicrobial Application.

The particle size at the nanometric level allows the manifestation of remarkable properties, chiefly due to changes in surface-to-volume ratio. This study is attributed to the novel green synthesis of nano silver by using essential oils as a capping and reducing agent. Clove oil, cinnamon oil, and cardamom oil were selected for the eco-friendly and low-cost fabrication of silver nanoparticles. The prepared nanoparticles were characterized by photoluminescence spectroscopy, FT-IR spectroscopy, X-Ray diffraction, energy dispersive X-ray spectroscopy, dynamic laser light scattering, thermogravimetric analysis, and transmission electron microscopy. It was found that samples prepared by using cinnamon oil (20 nm) and cardamom oil (12 nm) had smaller particle sizes as compared to those synthesized by using clove oil (45 nm). All the prepared samples exhibited very strong antimicrobial activities with a clear zone of inhibition (6-24 mm) against Staphylococcus aureus, Klebsiella pneumoniae, and Candida albicans. Very resilient photocatalytic activities of the samples were observed against Allura red and fast green dyes. It was concluded that the cinnamon oil-based system is the best size reducer and size homogenizer (less chances of agglomeration) as compared to clove oil and cardamom oil (more chances of agglomeration) for the synthesis of silver nanoparticles.

Facile Synthesis and Characterization of Chitosan Functionalized Silver Nanoparticles for Antibacterial and Anti-Lung Cancer Applications.

In the treatment of bacterial contamination, the problem of multi-drug resistance is becoming an increasingly pressing concern. Nanotechnology advancements enable the preparation of metal nanoparticles that can be assembled into complex systems to control bacterial and tumor cell growth. The current work investigates the green production of chitosan functionalized silver nanoparticles (CS/Ag NPs) using Sida acuta and their inhibition efficacy against bacterial pathogens and lung cancer cells (A549). Initially, a brown color formation confirmed the synthesis, and the chemical nature of the synthesized NPs were examined by UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS), and transmission electron microscopy (TEM). FTIR demonstrated the occurrence of CS and S. acuta functional groups in the synthesized CS/Ag NPs. The electron microscopy study exhibited CS/Ag NPs with a spherical morphology and size ranges of 6-45 nm, while XRD analysis demonstrated the crystallinity of Ag NPs. Further, the bacterial inhibition property of CS/Ag NPs was examined against K. pneumoniae and S. aureus, which showed clear inhibition zones at different concentrations. In addition, the antibacterial properties were further confirmed by a fluorescent AO/EtBr staining technique. Furthermore, prepared CS/Ag NPs exhibited a potential anti-cancer character against a human lung cancer cell line (A549). In conclusion, our findings revealed that the produced CS/Ag NPs could be used as an excellent inhibitory material in industrial and clinical sectors.

Phytochemical and Biological Screening of Catholic Vegetable (Jatropha Tanjorensis) Aqueous Extract in Bali, Taraba State, Nigeria

Jatropha tanjorensis has been used as a medicinal herb in treatment and management of disease because they are relatively safer, more affordable and sometimes offers better therapeutic value than synthetic drugs. The study investigated the phytochemical and biological screening of catholic vegetable (Jatropha tanjorensis) aqueous extract with the objectives of evaluating some secondary metabolites in the plant using standard qualitative methods and ascertaining the antimicrobial effect of Jatropha tanjorensis aqueous leave extract on bacteria of medical importance such as Pseudomonas aeruginosa, Klebsiella pneumonia, Staphylococcus aureus, Salmonella typhi and Escherichia coli using the agar well diffusion method. The results revealed that the extract of the leaf of J. tanjorensis contain some important bioactive components (phytochemicals) in a high amount such as saponins followed by flavonoids, alkaloid and tannins in moderate amount whereas phenol, phlobatannins and glycosides are in low amount. It also shows that the extract was active against E. coli, P. aeruginosa, S. aureus, K. pneumonia and S. typhi measuring clear zones of inhibition 30.0mm, 22.0mm, 19.0mm, 18.0mm and 17.0mm respectively. Thus, the exhibition of strong antibacterial activity and phytochemical profiles obtained from the analyses of J. tanjorensis leaf indicated that it might be recommended for human consumption and adequate amount of consumption could contribute greatly towards meeting human nutritional needs for normal body growth and adequate protection and curative measures to common diseases related to the test organisms.

Fabrication of antibacterial Fe3+-carboxymethylcellulose-polyacrylamide-Ag nanoparticles hydrogel coating for urinary catheters

Catheter-associated urinary tract infections (CAUTIs) are one of the most common hospital-acquired infections. In this study, a new Fe3+-carboxymethylcellulose (CMC)-polyacrylamide (PAAm) - Ag nanoparticles (AgNPs) interpenetrating hydrogel coating with antibacterial properties on the surfaces of latex urinary catheters was prepared with a simple dipping method. The morphology, chemical composition, surface roughness, and contact angles of the coated urinary catheters were characterized by using SEM, EDS, ATR-FTIR, XPS, AFM, and contact angle instruments, respectively. The antibacterial performance of the coated urinary catheters was characterized by the inhibition zone tests. Furthermore, the toxicity profile of the coated urinary catheters was also evaluated in vitro via MTT assay and hemolysis test. The experimental results showed that the Fe3+-CMC-PAAm-AgNPs hydrogel-coated urinary catheters had strong antibacterial effects. The concentration of AgNPs after the release of 30 days was still higher than the effective antibacterial concentration of the total Ag (0.1 ppb) and was lower than the toxic concentration of human cells (10 ppm). The inhibition zone tests of the coated urinary catheter against E. coli (ATCC25922) showed that both the CMC-PAAm-AgNPs hydrogel coatings and the Fe3+-CMC-PAAm-AgNPs hydrogel coatings had clear inhibition zones in the culture medium. The addition of Fe3+ exhibited synergistic antibacterial effects with AgNPs. Moreover, the coatings also showed admirable biocompatibility and hemocompatibility. The synergistic antibacterial mechanism was also proposed. The novel Fe3+-CMC-PAAm-AgNPs hydrogel coatings for urinary catheters would have great potential in reducing CAUTIs.

Phytochemical Analysis on Aqueous Leaf Extract of Justicia carnea (Acanthaceae) and its Antibacterial Activity on Some Isolated Bacterial

The present study was aimed to investigate the bioactive constituents and antibacterial efficacy of Justicia carnea leaf aqueous extracts on some pathogenic organisms involved in causing infections in humans. The antimicrobial and medicinal properties was examined through phytochemical screening of the plants constituents using standard qualitative methods and conducting bioassay on target bacteria of medical importance such as Escherichia coli, Salmonella typhi, Staphylococcus aureus, Klebsiella pneumonia and Pseudomonas aeruginosa using the agar well diffusion method. The screening revealed that tannins, saponins and alkaloids is highly detected followed by flavonoids that is moderately detected whereas phlobatannins, phenol and volatile oils are present in low amount. The result shows that the leaf extract was active against S. aureus, K. pneumonia, S. typhi, E. coli and P. aeruginosa measuring clear zones of inhibition 26.0mm, 22.0mm, 20.0mm, 18.0mm and 18.0mm respectively. Hence, the extracts exhibit strong antibacterial activity and could be used as a preventive and curative measures to common diseases related to the test organisms.

Microbiome protection against Coccidioidesgrowth

Abstract During infection, the host utilizes multiple mechanisms to prevent colonization and dissemination. Protection begins at the surface, often via the commensal community found within our respiratory, skin, and intestinal tract. Microbiota disruption reduces the effectiveness of this protective barrier. Coccidioidomycosis, or Valley fever, is often misdiagnosed as community acquired bacterial pneumonia and treated with antibiotics that alter microbiota density and diversity. Commensal bacteria influence host immune responses to infection, and antibiotic treatment alters host immunity. A soil microbial antagonist related to Bacillus subtilis inhibits in vitro growth of Coccidioides through a clear zone of inhibition between fungi and bacteria. Whether host microbiota also inhibits Coccidioides is unknown. To assess if host microbiota has inhibition capabilities against Coccidioides, we performed two inhibition assays and measured Coccidioides growth area. A 50/50 inhibition assay was performed in which host microbiota and Coccidioides were placed in direct competition on agar plates. A spike in inhibition assay was performed where host microbiota was grown to 80% confluency, to mimic an established in vivo microbiome, before spiking in Coccidioides. Our data indicate that intestinal and respiratory host microbiome species inhibit Coccidioides growth. To assess if host microbiota depletion allows greater Coccidioides growth, in vitro antibiotic disc diffusion assays and in vivo treatments were performed. Our data suggests that host respiratory and intestinal commensals inhibit Coccidioides growth. Antibiotic treatment may kill protective host bacteria that creates a niche for Coccidioides invasion. Supported by grant VFR-19-633952 from University of California Office of the President.

To study the anti-microbial effect of groundnut shell extract when applied on cotton fabric

Antimicrobial textile products are becoming increasingly popular as consumers seek fresh-smelling, skin-friendly, and high-performance fabrics. By imbuing the fabric with antimicrobial properties, we can increase the comfort and hygiene factor, making it more pleasant to wear. Odors can be neutralized, and skin problems caused by microbial growth can be reduced, emphasizing the treated product's hygiene. This research looks at extracting an antimicrobial finish from groundnut shells and applying it to cotton fabric. The hydrous (water) and solvent extraction processes were used for the extraction (methanol, ethanol). The Agar Diffusion Plate Method was used to test the antimicrobial efficacy of groundnut shell extract at different concentrations (20%, 40%, and 60%) with ethanol, methanol, and water. 20% methanolic extract for the Escherichia coli, the inhibition zone is greater than at other concentrations. For application, the fabric was desized and an iodine test was performed to check for the presence of starch before the finish was applied using the exhaustion and pad-dry-cure methods. The results show that for Escherichia coli, the fabric treated with groundnut shell extract along with 12% citric acid performed better than the extract alone. Until the fifth wash, the fabric sample treated with extract and 12% citric acid showed a clear zone of inhibition. The clarity decreased after the sixth, seventh, and eighth washes.

Bio-fabrication of zinc oxide nanoparticles from Picea smithiana and their potential antimicrobial activities against Xanthomonas campestris pv. Vesicatoria and Ralstonia solanacearum causing bacterial leaf spot and bacterial wilt in tomato.

Due to an inevitable disadvantage of chemical or physical synthesis routes, biosynthesis approach to nanoparticles, especially metallic oxide is attractive nowadays. Metallic oxides nanoparticles present a new approach to the control of plant pathogens. ZnO nanoparticles (ZNPs) have very important role in phytopathology. In current study, biosynthesized ZNPs were tested against two devastating bacterial pathogens including Xanthomonas campestris pv. vesicatoria and Ralstonia solanacearum causing bacterial leaf spot and bacterial wilt in tomato. ZNPs were produced using a new extract from the plant Picea smithiana using an environmentally friendly, cost-effective and simple procedure. Zinc acetate was added to P. smithiana extract, stirred and heated to 200°C. The white precipitation at the bottom were clear indication of synthesis of nanoparticles, which were further dried by subjecting them at 450°C. X-ray diffraction pattern determined that the ZNPs had a crystallite size of about 26nm, Fourier transform infrared spectroscopy indicated a peak between 450 and 550cm-1 and the particle size estimated by dynamic light scattering was about 25nm on average. Scanning electron microscopic analysis indicated that the particles were hexagonal in shape 31nm in diameter. Antibacterial tests showed ZNPs synthesized by P. smithiana resulted in clear inhibition zones of 20.1 ± 1.5 and 18.9 ± 1.5mm and 44.74 and 45.63% reduction in disease severity and 78.40 and 80.91% reduction in disease incidence in X. compestris pv. vesicatoria and R. solanacearum respectively at concentration of 100µg/ml. Our findings reveal that the concentration of ZNPs was important for their efficient antibacterial activity. Overall, the biosynthesized ZNPs have been found to have effective antimicrobial activities against bacterial wilt and bacterial leaf spot in tomato.

Formulation and characterization of polyherbal anti-acne gel containing Citrus aurantifolia and Aloe barbadensis extracts for the management of acne vulgaris

The antibiotic used to treat acne may develop antibiotic resistance and side effects. Meanwhile, treating acne-causing bacteria by applying Citrus aurantifolia juice to the skin immediately is ineffective. Citrus aurantifolia juice was employed in an anti-acne gel formulation to treat acne that was caused by Cutibacterium acnes and Staphylococcus epidermidis has no synergistic therapeutic effect shown. Additionally, polyherbal formulations are currently in high demand in the global market. The herbal industry's global market value has risen dramatically from US$60 billion in 2000 to US$105 billion in 2017. The worldwide market will increase at a rate of 7.6% each year until it reaches $5 trillion in 2050. This study aims to formulate a polyherbal anti-acne gel containing C. aurantifolia and Aloe barbadensis, and to characterize the formulated gel for its physicochemical properties. The phytoconstituents found in plant extracts were also analysed. The antibacterial activity of plant extracts against Staphylococcus aureus was also investigated using an agar well diffusion method. After plant extracts were discovered, gels with varying concentrations of plant extracts, and excipients were prepared along with compatibility studies. Parameters like colour, odour, homogeneity, phase separation, consistency, washability, pH, viscosity, spreadability and antibacterial activity were evaluated. The results showed that the levels of phenol, tannins, and flavonoids in plant extracts varied, the antibacterial activity of plant extracts was studied with a clear inhibition zone demonstrated, and plant extracts were compatible with all excipients. Gel formulations containing C. aurantifolia, A. barbadensis, the excipients Carbopol-940, methylparaben, propyl paraben, propylene glycol-400, triethanolamine and water have been developed. The formulated gels were clear, odourless, uniform, consistent, without lumps, and washable. It was found that pH was closer to the skin, good viscosity and spreadability. The formulated gel, F4 has greater antibacterial activity than plant extracts and other formulations with a larger diameter inhibition zone. It is concluded that the polyherbal anti-acne gel containing C. auranfolia and A. barbadensis can be formulated which has a high potential for halal cosmetics product development. However, more research should be done before it can be commercialised by comparing it to commercially available marketed formulations to treat acne vulgaris.

Tungsten-based hybrid nanocomposite thin film coated fabric for gamma, neutron, and X-ray attenuation

Ionizing radiation such as x-ray, γ-ray and neutron ray have serious negative health effects on human being. Hence, new and smart textile fabric nanocoating was facilely developed and coated on lab coat cloth. The newly hybrid nanocoatings were fabricated from uniform dispersion of PbWO4 NPs and Bi2WO6 NPs of an average sizes of 47.38 ± 7.6 and 9.1 ± 1.8 nm, respectively in chitosan solution. The dispersion of tungsten-based nanoparticles was performed using ultrasonication process, then well dispersed hybrid nanocoatings were coated on textile fabrics derived lab coat. The mass ratio of nanoparticles in nanocoatings were altered and optimized. The attenuation properties of x-ray/gamma ray and neutron ray were studied and achieving good shielding properties compared to uncoated fabrics. Additionally, the antibacterial and mechanical properties of coated fabrics were evaluated. The coated textile fabrics achieved clear inhibition zone of 4 mm compared to zero clear inhibition zone for uncoated ones against E-Coli. Moreover, the developed coating layer achieved good reinforcement effect recording superior tensile strength by 11.5% than uncoated sample. The dispersion properties of nanoparticles in coating nanocomposites were investigated using microscopic tools.

Levofloxacin HCl-Incorporated Zein-Based Solvent Removal Phase Inversion In Situ Forming Gel for Periodontitis Treatment.

Zein is composed of nonpolar amino acids and is a water-insoluble protein used as the matrix-forming agent of localized in situ forming gel (ISG). Therefore, this study prepared solvent removal phase inversion zein-based ISG formulations to load levofloxacin HCl (Lv) for periodontitis treatment using dimethyl sulfoxide (DMSO) and glycerol formal (GF) as the solvents. Their physicochemical properties were determined, including viscosity, injectability, gel formation, and drug release. The topography of dried remnants after drug release was revealed using a scanning electron microscope and X-ray computed microtomography (μCT) to investigate their 3D structure and % porosity. The antimicrobial activities were tested against Staphylococcus aureus (ATCC 6538), Escherichia coli ATCC 8739, Candida albicans ATCC 10231, and Porphyromonas gingivalis ATCC 33277 with agar cup diffusion. Increasing zein concentration or using GF as the solvent notably enhanced the apparent viscosity and injection force of the zein ISG. However, its gel formation slowed due to the dense zein matrix barrier's solvent exchange: the higher loaded zein or utilization of GF as an ISG solvent prolonged Lv release. The SEM and μCT images revealed the scaffold of dried ISG in that their % porosity corresponded with their phase transformation and drug release behavior. In addition, the sustainability of drug diffusion promoted a smaller antimicrobial inhibition clear zone. Drug release from all formulations was attained with minimum inhibitory concentrations against pathogen microbes and exhibited a controlled release over 7 days. Lv-loaded 20% zein ISG using GF as a solvent exhibited appropriate viscosity, Newtonian flow, acceptable gel formation and injectability, and prolonged Lv release over 7 days with efficient antimicrobial activities against various test microbes; thus, it is the potential ISG formulation for periodontitis treatment. Consequently, the Lv-loaded solvent removal zein-based ISGs proposed in this investigation offer promising potential as an efficacious drug delivery system for periodontitis treatment by local injection.

Reinforcement and Antibacterial Properties of Hand Embroidery Threads Based on Green Nanocoatings

This paper presents a novel design and synthesis strategy for smart antibacterial and reinforcement coatings for hand embroidery threads. For the first, time molokhia stem extract was prepared and utilized as a reducing and capping agent for the synthesis of a uniform narrow-sized dispersion of ZnONPs, with an average size of 10 nm. This was then wrapped with starch chains and coated on hand embroidery threads. The ZnONP size and dispersion were elucidated using microscopic techniques. The tensile strength and antibacterial properties for the developed cotton threads were studied. The new green nanocoatings enhance the tensile strength of hand embroidery threads by 7% and record potential antibacterial behavior. The developed threads inhibit the growth of bacteria and record a clear antibacterial inhibition zone of 8.5 mm compared to zero for the uncoated one. The dispersion and morphology of the nanocoating on the surface cotton threads were investigated using SEM-EDS. The current study affords a green and scalable approach for the new generation of safe and green hand embroidery products.

Biosynthesis and Characterization of CdO: Ag NPs using Moringa Leaves Extract for Use as Anti-microbial Activity

The current research focuses on synthesizing cadmium oxide (CdO), CdO: Ag nanoparticle (NPs) by green method using the Moringa leaves Extract (MLE) and its anti-microbial activity. Using UV-vis spectroscopy to determine the formation of CdO: Ag NPs where the energy gap of the prepared samples was 2.79, 2.67, and 2.46 for CdO, CdO: Ag 3% and CdO: Ag 5%, respectively. The biological substances in responsibility of capping the produced NPs were identifi ed using FTIR. The NPs were further characterized by X-ray diff ractograms (XRD). The average grain size for CdO, CdO: Ag (3 and 5%) were 15.322, 15.5, and 36.84 nm, respectively, scanning electron microscope (SEM), energy dispersive X-ray (EDX) and atomic force microscope (AFM), were obtained the average diameter 18.88, 43.48, 99.15 nm for CdO, CdO: Ag 3% and CdO: Ag 5%, respectively. The anti-bacterial activity of green synthesized CdO: Ag(NPS) was investigated against (Staphylococcus aureus, Escherichia coli, and Klebsiella pneumonia) at diff erent concentrations, showing clear inhibition zones from 30 to 38 mm, thereby indicating its inhibitory activity.

Nanoporous carbon doped with metal oxide microsphere as renewable flame retardant for integrating high flame retardancy and antibacterial properties of thermoplastic polymer composites

Innovative, renewable and cost-effective porous composites were developed for integrating high fire safety and antibacterial properties for thermoplastic polymers. Sustainable porous carbon sheets were developed from plum stones as fruits-by-products via single carbonization step affording dual environmental and economic benefits. The as-developed porous carbon own specific surface area of 165 m2 g−1 which is characteristic of mesoporous feature of an average mesopore size of 2.1 nm, in addition to naturally doped nitrogen species. The obtained porous carbons sheets were dispersed in different mass loadings in to polystyrene matrix-producing polymer composites. Interestingly, SnO2 microsphere of an average size of 2 µm was synthesized on the surface of developed porous carbon sheets producing new porous composites. The new composites were elucidated using XRD, FT-IR and SEM–EDS. Then, the developed composites were dispersed in polystyrene. The mass loadings were altered and studied. The progress in fire safety, thermal stability and antibacterial properties for developed polymer composites was studied. The flame retardancy of the new composites was significantly improved achieving rate of burning of 20.5 mm min−1 compared to 46.5 mm min−1 for blank polymer. This superior flame retardancy was corroborated by recording LOI value of 24.5% compared to 18% for virgin polymer. This attained flame retardancy was ascribed to the synergistic effect between porous carbon sheets contained nitrogen and SnO2 microsphere. The new composites afford promising inhibition for bacterial growth achieving clear antibacterial inhibition zone of 11 mm compared to zero for blank sample. The flame retardancy action was studied and elucidated.

Chemical Synthesis of a Polyvinylpyrrolidone-Capped Silver Nanoparticle and Its Antimicrobial Activity against Two Multidrug-ResistantAeromonas Species

This study investigated the antimicrobial activity of polyvinylpyrrolidone-capped silver nanoparticles (PVP-AgNPs) in vitro against two antibiotic-resistant isolates of Aeromonas hydrophila and A. caviae. Solid crystal silver nanoparticles were synthesized by the chemical reduction approach employing polyvinylpyrrolidone (PVP) as a neutral stabilizer, glucose as a reducing agent, and sodium hydroxide as a catalyst. The crystallinity and purity of the prepared PVP-AgNPs were investigated using the X-ray diffraction spectrometer (XRD). Transmission electron micrograph analysis demonstrated the formation of irregular spherical shapes PVP-AgNPs with average crystallite size diameters ranging from 5.07 to 9.74 nm. By phenotypic and gene sequence analysis, A. hydrophila and A. caviae isolates were identified from diseased Nile tilapia. Our findings showed that all A. hydrophila and A. caviae isolates were multidrug-resistant (MDR) and showed resistance to four antimicrobial classes. The PVP-AgNPs displayed 15 mm and 14 mm clear inhibition zones for A. hydrophila and A. caviae, respectively. In addition, the minimum inhibitory concentrations for PVP-AgNPs were estimated to be 6.25 μg/ml and 7.5 μg/ml for A. hydrophila and A. caviae, respectively. The chemically synthesized PVP-AgNPs were found to possess a strong antimicrobial effect against A. hydrophila and A. caviae with the possibility to be used as a commercialized antimicrobial agent in the aquaculture industry.

Probiotics in dermatological therapy and skincare

Probiotics are characterised as “live microorganisms'' and use of probiotics has shown promising effects on the prevention and treatment of different inflammatory skin disorders such as acne and atopic dermatitis. The Lactobacillus sp. were isolated using fermented rice water. Fermented rice water was serially diluted and plated on MRS Medium plates in which the bacterial isolates were observed to be round, flat, slightly mucoid, creamy in colour. The Lactobacilli was confirmed by Gram staining and the slide was observed to be gram positive rod shaped. Biochemical test was also performed in which TSI slant was observed with red slant, yellow butt without gas and H2S formation. Screening was done for Lactobacillus sp. for probiotic properties. Optimal growth was determined at 560 nm at pH 5.5. NaCl concentration tolerance at 4% was observed to be optimal. The antimicrobial activity of the isolated Lactobacillus was identified by a well diffusion method and was diameter up to 0.8, 0.6 & 1.2 cm. Supernatants of each sample of Lactobacillus were monitored for antibacterial activity against indicator bacteria Bacillus, Pseudomonas inoculated on Nutrient agar and presence of clear zones of inhibition around the wells were observed. Antibiotics sensitivity test Disk diffusion method was performed and zones of inhibition around the disks were observed. Shea butter, raw honey and aloe vera gel along with that Pellets of Lactobacillus species were added and tea tree oil and essential oils were added drop by drop and this probiotic face serum was stored. The lab made face serum was further dissolved insterilised distilled water and a loopful was inoculated to the Nutrient medium containing petri plates for determining the viability of lactobacillus species after incubation.