Average Diameter Research Articles

Effect of The Temperature on The Size of Inhibition Zone of the Clindamycin, Levofloxacin, Tetracycline, and Trimethoprim Activity Against Staphylococcus aureus ATCC 25923

Antibiotic sensitivity should be tested. In the sensitivity test, there are technical factors that influence the formation of the inhibition zone diameter. Based on several research one of the technical factors that affect the diameter of the inhibition in the disc diffusion method is the temperature incubation of the media, this must be examined so that it can be controlled to ensure the validity of the sensitivity test results. This study aims to determine the mean, difference, and analyze the diameter of the inhibition zone of the antibiotics namely Clindamycin, Levofloxacin, Tetracycline, and Trimethoprim against Staphylococcus aureus on Mueller-Hinton agar media with incubation temperatures of 33°C, 34°C, 35°C, 36°C and 37°C for 18 hours. This research is observational, with a cross-sectional design. The data used are primary data with 100 data on the diameter of the antibiotic inhibition zone, obtained by measuring the diameter of the inhibition zone with different incubation temperatures. The selection of antibiotics is based on the mechanism of action of antibiotics inhibiting bacteria namely, the cell wall or membranes that surrounds the bacterial cell; the machineries that make the nucleic acids DNA and RNA and the machinery that produce proteins (the ribosome and associated proteins) with a range of inhibition zones based on Internal Quality Control CLSI. The data will be processed univariately and the Repeated Measure statistical test to determine the significance of the difference in the diameter of the formed inhibition zone using the ANOVA test. The results of the measurement of the inhibition zone diameter on the incubation temperature variation showed a significant difference with p-value 0.000 for Levofloxacin, Tetracycline and Trimethoprim, while for p-value Clindamycin is 0.010. Levofloxacin, Tetracycline, and Trimethoprim antibiotics, the higher the incubation temperature, the average diameter of the inhibition zone is smaller, while for Clindamycin the higher the incubation temperature, the higher the average diameter of the inhibition zone is the same. There is an effect of incubation temperature volume on the diameter of the antibiotic inhibition zone in the disc diffusion method antibiotic sensitivity test. The research indicates that incubation temperature affects the diameter of the antibiotic inhibition zone in disc diffusion tests, underscoring the need for standardized and precise testing conditions to ensure accurate and reliable antibiotic sensitivity results.

Janus nanoparticles synthesized from hydrophobic carbon dots and carboxymethyl cellulose: Novel antimicrobial additives for fresh food applications

The aim of this study was to synthesis Janus nanoparticles (JPs) using beeswax-based hydrophobic carbon dots to form the non-polar face and hydrophilic carboxymethyl cellulose to form the hydrophilic face. Size, morphology, composition, and optical properties of the JPs were characterized. Scanning electron microscopy and light scattering analysis showed these nanoparticles were spheroids with average diameters around 4 nm. A cytotoxicity assay (L929 cells) showed that the hydrophobic carbon dots and JPs exhibited significant toxicity (decrease in cell viability) at 1.5 and 5 mg/mL, respectively. For the hydrophobic carbon dots, the minimum inhibitory concentration was 0.02 mg/mL for Escherichia coli and 0.04 mg/mL for Listeria monocytogenes, whereas for the JPs it was 0.04 mg/mL for both bacteria. Both the hydrophobic carbon dots and JPs also exhibited appreciable antioxidant activity. These particles were then incorporated into minced beef as novel preservatives. At 0.05% concentration, both kinds of nanoparticles caused a significant reduction in chemical and microbial degradation of the meat during storage. The JPs had a greater effect on mesophile (3.3 log10 CFU/g reduction) than on psychrophile (2.8 log10 CFU/g reduction) microbial populations within the meat. The preparation of JPs based on carbon dots, reduced cytotoxicity and improved their antimicrobial properties. JPs developed in this study may be used as novel preservatives with antimicrobial and antioxidant properties in foods.

Harnessing the power of ternary nanocomposites: Iron oxide, multiwalled carbon nanotubes, and bentonite for superior ciprofloxacin adsorption

Water contamination from antibiotics can have detrimental effects on one’s health. Consequently, treating the polluted water is required to fix this issue. Fe3O4-multiwalled Carbon Nanotubes (MWCNTs)-Bentonite nanocomposite has been successfully prepared using a customized co-precipitation process. The synthesized nanocomposite was used as an adsorbent to extract the ciprofloxacin from aqueous solutions. The synthesized nanocomposite was examined using several characterization methods. Scanning electron microscopy demonstrates that the Fe3O4 nanoparticles and bentonite are well-decorated on MWCNTs. The nanocomposite exhibits a high BET surface area of 221.577 m2/g and a pore volume of 0.411 cm3/g. According to the analysis, the average pore diameter was found to be 3.717 nm. Additionally, the adsorption model agreed with the Jovanovic model, which had a 137.35 mg/g adsorption capacity, with a χ2 of 2.161, and a good nonlinear R2 value of 0.999. Moreover, adsorbent was found to be highly stable even after 4 cycles. The ΔS and ΔH values were found to be positive, which suggested an endothermic process. The synthesized nanocomposite proved to be a viable option for water treatment applications, and there is no literature available on CIP antibiotic adsorption using Fe3O4-MWCNT-Bentonite nanocomposite.

Enhancing Growth of Upland Rice in Low-Phosphorus Soil by Leveraging Root Morphological Traits

Low phosphorus (P) in the upland ecosystems negatively, influence rice growth and causes significant yield losses. In the present study, 9 upland rice genotypes were screened to identify root traits that support the growth in low P soil in a cement tank. Rice genotypes showed significant (p = ≤ 0.05) variation for number of root tips (NRT), number of root branching points (NBP), total root length (TRL), whole root network area (NA), average root diameter, root volume (RV), root surface area (RSA), first order root length (FORL), and second order root length (SORL). BW01 and ITA01 recorded the highest NRT, NBP, TRL, RV, NA, RSA, FORL and SORL while NERICA04 had the lowest representing 5.8, 8.0, 7.6, 6.8, 9.0, 5.8, and 9.3 differences in these traits under low P soil. NRT significantly positively correlated with NBP, TRL, NA, RV, RSA, FORL indicating the role of different root traits in foraging for soil nutrients. The principal component analysis (PCA) showed that the NRT, NBP, TRL, RSA and SORL are important and effective root traits for selection in rice breeding under low P soil supply. BW01 and ITA01 recorded well developed root system indicating that they are P-efficient than P-inefficient NERICA04 under low P soil conditions. Therefore, BW01 and ITA01 can targeted for cultivation in P deficient soils and also used as donor of novel root traits to improve P-inefficient rice cultivars.

A Comparison Study of Photocatalytic Performance of TiO2 Anatase Phase Prepared from Different Procedures

In this work, three TiO2 anatase phase samples, labeled as S1, S2, and S3, were synthesized using varying titanium precursors, solvents, and conditions to compare their photocatalytic performances. The structural and morphological properties of the synthesized samples were characterized through X-ray diffraction (XRD), Raman scattering, field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). The obtained results indicated that all samples exhibited an anatase crystalline phase. Sample S1 notably featured nanowires with an average diameter of 38.6 nm. Meanwhile, samples S2 and S3 comprised nanoparticles, each exhibiting unique average sizes of 12.76 nm and 10.11 nm, respectively. The diffuse reflectance spectra reveal that the S3 sample possesses the lowest bandgap, suggesting its potential as the most promising photocatalyst. Additionally, photocurrent response and electrochemical impedance spectroscopy (EIS) were characterized to elucidate the charge transfer mechanisms within the materials. The degradation efficiencies of Rhodamine B (RhB) for samples S1, S2, and S3 were determined to be 17.40%, 17.93%, and 33.04%, respectively, under visible light irradiation. This study provides valuable insights into the criteria for choosing efficient TiO2 photocatalysts.

Cloud point extraction and characterization of zinc oxide nanoparticles isolated from infant milk formulas

The increasing presence of nanoparticles in food products, especially in those consumed by sensitive populations like infants, raises justified health concerns. The presence of zinc oxide nanoparticles (ZnO-NPs) in three different commercial infant milk formulas were analyzed. In addition, one maternal food supplement was included in this study. Notably, existing regulations lack specificity regarding the size distribution of nanoparticles (NPs) and the maximum permissible concentrations in commercial infant products. Except in one sample, the total zinc content exceeded the reported amount in the nutritional label, which varied from 34 to 119 µg/g. This work validated the cloud point extraction (CPE) technique for the effective isolation of ZnO-NPs from the selected products. CPE was then used to evaluate the ZnO-NPs concentrations in commercially available infant formulas and maternal supplements. Using inductively coupled plasma optical emission spectrometry (ICP-OES), the ZnO-NPs and total Zn concentrations were determined. The ZnO-NPs concentration ranged from 16 to 39 µg/g, representing a considerable portion of the total zinc content. Transmission electron microscopy (TEM) analysis indicated the presence of nanoparticles with an average diameter of 6.3 nm. The NPs size could determine their cell internalization, and thus, the potential cytotoxic effects are discussed. These findings underscore the need for rigorous isolation and quantification of nanoparticles from infant milk formulas, and as an inevitable first step for in vitro and in vivo toxicity studies to address the potential health impact of nanoparticles in food products.

Research on the microscale effects of fuel pellets carrying chemical pesticide distillation residues

To effectively deal with organic hazardous wastes generated in the production processes of chemical pesticide industries. In this study, the strong shear force generated by high-speed rotating blades was utilized to fully mix and stir pasty or viscous liquid organic hazardous wastes with porous solid fuels. The wastes were broken down into small molecular clusters and evenly distributed on the surfaces of the pores of porous solid fuel particles. This study then investigated the thermal characteristics of fuel particles carrying the distillation residues of chemical pesticides under microscale effects, the volatilization and destruction removal characteristics, the formation of pollutants, and the migration and transformation of F and Cl elements. The results showed that when the average diameter of the fuel particles was 6 mm and the mass ratio of the chemical pesticide distillation residue to the fuel particles was 2:3, small molecular clusters of the residue were evenly distributed on the surfaces of the fuel particles, with a dispersity of 67 %. The volatilization rate of the irritating odors in the coated particles was less than 2 %. With an increase in the proportion of the chemical pesticide distillation residue, the ignition temperature of the particles decreased, the thermal stability increased, the burnout temperature rose, and the maximum weight loss rate first increased and then decreased. The Ca and alkali metal oxides in the fuel particles had a significant effect on fixing chlorine and fluorine.

Sustainable extraction of cellulose nanocrystals from empty palm oil bunches via low-acid hydrolysis

The increasing production of empty palm oil bunches (EPOB) poses significant environmental challenges due to waste accumulation. This study aims to convert EPOB into valuable cellulose nanocrystals (CNCs) through a sustainable extraction process utilizing low-acid concentration. The extraction method involves three key steps: alkalization, bleaching, and hydrolysis with 30 % sulfuric acid. The results indicate a high α-cellulose content of 87.04 % and an increase in crystallinity of the extracted CNCs to 60.28 %, as confirmed by X-ray diffraction analysis. The CNCs exhibit a rod-like morphology with an average diameter of 1.66 nm and a length of 9.85 nm. This research demonstrates that EPOB can be effectively transformed into high-quality CNCs, providing a cost-effective and environmentally friendly alternative for utilizing agricultural waste. The findings support the potential application of CNCs in various fields, including biodegradable materials and coatings, contributing to sustainability in the palm oil industry.

Colletotrichum species associated with anthracnose disease on mango (Mangifera indica L.) cv. Azúcar in Colombia

The role of some Colletotrichum species is uncertain in crops of economic importance for Colombia such as mango (Mangifera indica L.) cv. Azúcar. Eight Colletotrichum isolates from asymptomatic plant tissues were characterized by their pathogenicity on fruits and identified by phylogenetic analysis of the sequences of the ITS, GADPH, Tub2, CHs-1 and Act genomic regions. Colletotrichum asianum, C. gloeosporioides and C. tropicale of the C. gloeosporioides species complex and C. karstii of the C. boninense species complex were identified. The highest virulence was observed for isolates of C. asianum, that was the most prevalent species, and for C. tropicale, that showed high and intermediate virulence levels, indicating diversity in pathogenicity within the same species. The isolate of C. karstii, which displayed intermediate virulence, is the first report on mango in Colombia. Colletotrichum gloeosporioides presented intermediate virulence and was isolated at a low frequency in the present research. The mycelial growth rate did not show differences between species and ranged between 6.1 and 8.3 mm per day. Colletotrichum asianum recorded higher values of conidia germination and appressoria formation than other species, at 77% and 79%, respectively (p < 0.001). The shape and size of conidia did not vary between species. Appressoria exhibited different shapes between isolates and the largest average diameter was for C. karstii with 7.6 µm (p < 0.001). There was a diversity of Colletotrichum species associated with mango cv. Azúcar in Colombia, with differential virulence among isolates of the same species.

Preparations of Polyurethane Foam Composite (PUFC) Pads Containing Micro-/Nano-Crystalline Cellulose (MCC/NCC) toward the Chemical Mechanical Polishing Process.

Polyurethane foam (PUF) pads are widely used in semiconductor manufacturing, particularly for chemical mechanical polishing (CMP). This study prepares PUF composites with microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC) to improve CMP performance. MCC and NCC were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD), showing average diameters of 129.7 ± 30.9 nm for MCC and 22.2 ± 6.7 nm for NCC, both with high crystallinity (ca. 89%). Prior to preparing composites, the study on the influence of the postbaked step on the PUF was monitored through Fourier-transform infrared spectroscopy (FTIR). After that, PUF was incorporated with MCC/NCC to afford two catalogs of polyurethane foam composites (i.e., PUFC-M and PUFC-N). These PUFCs were examined for their thermal and surface properties using a differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), dynamic mechanical analyzer (DMA), and water contact angle (WCA) measurements. Tgs showed only slight changes but a notable increase in the 10% weight loss temperature (Td10%) for PUFCs, rising from 277 °C for PUF to about 298 °C for PUFCs. The value of Tan δ dropped by up to 11%, indicating improved elasticity. Afterward, tensile and abrasion tests were conducted, and we acquired significant enhancements in the abrasion performance (e.g., from 1.04 mm/h for the PUF to 0.76 mm/h for a PUFC-N) of the PUFCs. Eventually, we prepared high-performance PUFCs and demonstrated their capability toward the practical CMP process.

Radiation Resistance of High-Entropy Alloys CoCrFeNi and CoCrFeMnNi, Sequentially Irradiated with Kr and He Ions.

This work studied the effect of sequential irradiation by krypton and helium ions at room temperature on the composition and structure of CoCrFeNi and CoCrFeMnNi high-entropy alloys (HEAs). Irradiation of the HEAs by 280 keV Kr14+ ions up to a fluence of 5 × 1015 cm-2 and 40 keV He2+ ions up to a fluence of 2 × 1017 cm-2 did not alter their elemental distribution and constituent phases. Blisters formed on the nickel surface after sequential irradiation, where large blisters had an average diameter of 3.8 μm. The lattice parameter of the (Co, Cr, Fe and Ni) and (Co, Cr, Fe, Mn and Ni) solid solutions increased by 0.17% and 0.37% after sequential irradiation, respectively. Irradiation by Kr ions led to a decrease in tensile macrostresses in the HEAs in the region of krypton ion implantation (Region I) and the formation of compressive macrostresses in the region behind the peak of implanted krypton (Region II). Sequential irradiation formed large compressive stresses in Ni and HEAs equal to -131.5 MPa, -300 MPa and -613.5 MPa in Ni, CoCrFeNi and CoCrFeMnNi, respectively, in the Region II. Irradiation by krypton ions decreased the dislocation density by 1.6-2.3 times, and irradiation with helium ions increased it by 11-15 times relative to unirradiated samples for CoCrFeNi and CoCrFeMnNi, respectively. Sequentially irradiated CoCrFeMnNi HEA had higher macrostresses and dislocation density than CoCrFeNi.

The Development of Uniform-Sized Pt-Based Binary Alloy Electrocatalysts for ORR in Polymer Electrolyte Fuel Cells

Developing a highly efficient and durable reduced platinum metal (PtM) alloy catalyst with high oxygen reduction reaction (ORR)activity for polymer electrolyte fuel cells (PEFCs) is of significant interest. In this study, platinum-iron (PtFe), platinum-nickel (PtNi), and platinum-cobalt (PtCo) alloys were prepared with an average diameter of ca. 3 nm, uniformly dispersed on a high surface area carbon. The ORR activity of the prepared PtM/C catalysts was investigated under both RDE and MEA conditions. The resulting PtM/C catalysts demonstrated improved I-V cell performance at low-current density (LCD) and high-current density (HCD) regions. These findings suggest that high ORR activity and enhanced durability can be achieved through the formation of uniform Pt skin with higher electrochemical surface area (ECSA).

Assessing polylactic acid nanofibers with cellulose and chitosan nanocapsules loaded with chamomile extract for treating gram-negative infections.

This study presents the development and characterization of a novel nanocomposite wound dressing material based on polylactic acid (PLA) nanofibers incorporating chitosan nanocapsules loaded with chamomile extract and cellulose nanoparticles. The nanofibers were fabricated using a three-step synthesis and electrospinning techniques, resulting in uniform, bead-free fibers with an average diameter of 186 ± 56nm. Fourier-transform infrared spectroscopy confirmed the successful incorporation of all components, while tensile strength tests demonstrated improved mechanical properties by adding nanoparticles. Water contact angle measurements revealed enhanced surface wettability of the PLA-Cellulose-Chitosan complex compared to pure PLA nanofibers. In vitro biocompatibility assessments using MTT assays showed excellent cell viability and proliferation, with the optimized composite exhibiting the best performance. Scanning electron microscopy imaging confirmed robust cell adhesion and interaction with the nanofibers. The nanocomposite demonstrated significant antimicrobial activity against Escherichia coli, with a 20mm inhibition zone observed for chamomile extract-loaded samples. Additionally, the material showed superior hemostatic ability compared to commercial gauze and high hemocompatibility. These comprehensive results indicate that the developed nanocomposite is a promising candidate for advanced wound management applications, offering a multifunctional approach to wound healing by combining antimicrobial activity, cell compatibility, and hemostatic properties.

Effects of volatile fatty acids on soil properties, microbial communities, and volatile metabolites in wheat rhizosphere of loess

The Loess Plateau faces critical challenges due to soil degradation. In this context, using volatile fatty acids (VFAs) from biowaste as readily available soil conditioners offer promising sustainable solutions to restore soil quality and enhance agricultural productivity. The study examined how applying different VFAs as soil amendments in arid and high-salt loess soil affected wheat plant growth, soil properties, soil microbial community diversity, volatile metabolites in soil and root exudate. The non-targeted analysis was used to identify and classify 49 soil volatile organic compounds (VOCs) and 63 root exudate VOCs to seek further specific functional volatile metabolites and explore the interaction mechanisms among plants, microorganisms, and soil. The results showed that acetic acid increased soil EC by 21.0% and decreased soil organic matter by 14.4%. Propionic acid reduced soil organic matter by 14.7%. Valeric acid increased the average root diameter by 15.1%. Further analysis revealed that rhizosphere bacterial communities, but not fungal communities, showed greater sensitivity to VFAs application. Bacterial α diversity was significantly reduced in the acetic acid treatment. The main contribution of VOCs in soil with acetic acid and propionic acid applications was alcohol, and its relative percentage was 50.06% and 43.54%, respectively, which has a significantly negative correlation with the α diversity of soil bacteria. On the contrary, the content of acylamides in soil with butyric acid and valeric acid applications was higher and significantly positively correlated with the average root diameter. It was concluded that soil microbial communities respond rapidly to acetic acid, propionic acid, butyric, and valeric acid applications by adjusting the concentration of alcohols and acylamides as secondary metabolites, respectively. This study revealed the close relationship between VFAs application type and soil properties, soil microbial community diversity, soil VOCs, and root exudates VOCs. VFAs derived from biowaste will contribute to restoring loess soil quality and achieving sustainable agriculture.

Bovine serum albumin and lysozyme nanofibers as versatile platforms for preserving loaded bioactive compounds

In this study, the electrospinning procedure was optimized to create polyethylene oxide (PEO) NFs highly enriched in proteins with non-structural functions while preserving their activity. For this purpose, several immune-related proteins of low, medium and high molecular weights were used as molecular models. Initially, the electrospinning parameters were adjusted using 3 % w/w PEO and bovine serum albumin (BSA, 5–20 % w/w). As determined by FESEM, their average diameters ranged from 301 to 752 nm, and those with higher protein content (15–20 %) yielded more uniform NFs in both size and morphology terms. Protein integrity remained stable as determined by SDS-PAGE and FTIR. Similar results were observed for the polypeptide lysozyme (LYZ) when incorporated in NFs under these settings. To further explore the potential of these materials, the antimicrobial peptide piscidin (PIS) and an antibody (Ab, HRP-IgG) were used to produce BSA/PIS, LYZ/PIS and BSA/Ab NFs and evaluate the preservation of their activity. The antibacterial assays showed that, in most bacterial species, the activity of PIS remained consistent after being incorporated into the NFs. Furthermore, the activity of HRP-IgG was maintained within the NFs, with enhanced preservation observed in BSA/Ab NFs. These findings expand the possibilities of protein utilization across various applications through nanomaterials.

Study of the kinetics and mechanisms of rare earth elements leaching from end-of-life NdFeB magnets through Hydro-Nd process

With the growing demand for REEs in numerous high-tech and energy transition-related applications, recycling these elements from secondary sources, mainly from end-of-life permanent magnets, has become crucial for responsible sourcing of raw materials from a circular economy. To date, numerous processes have been developed and optimized to allow this recovery to be sustainable from both an economic and environmental point of view. In this context, hydrometallurgy is one of the most promising avenues. Through an innovative hydrometallurgical process (Hydro-Nd), this research investigated the kinetics and mechanisms involved in leaching REEs from end-of-life permanent magnets. This process involves the use of citric acid in the leaching phase. Through systematic experimentation and analysis, the article elucidates key factors influencing leaching kinetics, providing insight into critical mechanisms of the process. In particular, ANOVA was used to study the influence of important factors (temperature, particle size, and agitation) on the recovery yields of the elements of interest. The shrinking core model studied the leaching mechanisms to identify a possible rate-determining step. Thanks to the results obtained, the Arrhenius parameters were estimated for the different heterogeneous reactions involved in the process, and the trend of the time constants versus the average diameter of the solid particles was identified. Also, the results showed that 100 % of Nd, Fe, Dy, B, and Pr from small PM particles (0–40 µm) in 4 h and more than 90 % of the mentioned metals from large particles (1000–1700 µm) within 5 h of leaching time were dissolved by citric acid solution. This research not only contributes to the development of an even more sustainable rare earth recovery process thanks to the optimization of several factors but also clarifies fundamental aspects of leaching kinetics and mechanisms, paving the way for future advances in the recovery of REEs from different sources.

UV-crosslinked collagen-chondroitin sulfate nanofibers: Insights on production, characterization, in-vitro digestibility

Electrospun polymer nanofibers have significant attention in various fields. In this study, collagen/chondroitin sulfate (Col/CS) nanofibers were fabricated by electrospinning, the effect of solution and processing parameters on fiber morphology was investigated. The resulting fibers were exposed to UV light for the crosslinking process. Granola bars with Col/CS nanofibers were prepared and subjected to in vitro digestion. The electrospun Col/CS nanofibers, fabricated at a 95:5 (w/w) ratio under 26 kV voltage, 0.8 mL/h feeding rate, and a 15 cm tip-to-collector distance, exhibited a smooth, bead-free fibrous morphology with an average diameter of 79.88 ± 6.01 nm. After UV-crosslinking, no new bands were observed in the FTIR spectrum, but notable changes occurred in the Amide I and II regions. Granola bars containing Col/CS nanofibers exhibited significantly higher Col content in the intestinal digestion fraction of in vitro digestion compared to the control group (free Col + CS). On the other hand, no significant difference was observed between the CS content of the samples after intestinal digestion. These findings demonstrate that electrospinning followed by UV crosslinking is an effective method for producing Col/CS fibers without the use of harsh solvents, highlighting Col/CS nanofibers as promising candidates for the development of novel functional foods.

Polymer functionalized antimony sulfide quantum dots for broadband optical limiting.

The rapid development of zero-dimensional quantum dots-based nanotechnology has motivated the design and synthesis of novel nano-functional materials for optoelectronic and photonic devices in recent years. Antimony sulfide (Sb2S3) quantum dots (SQDs), with an average diameter of 3.22 nm, were prepared via a top-down liquid ultrasonication exfoliation technique. Highly soluble poly(N-vinylcarbazole)-covalently functionalized SQDs (SQDs-PVK) were synthesized in situ by reversible addition fragmentation chain transfer polymerization, and embedded into a non-optically active poly(methylmethacrylate) (PMMA) matrix giving the SQDs-PVK/PMMA film. The annealed SQDs-PVK/PMMA film showed exceptional nonlinear optical performance, with large nonlinear absorption coefficients of 713.71 cm GW-1 at 532 nm and 913.60 cm GW-1 at 1064 nm, and small limiting thresholds of 1.44 J cm-2 at 532 nm and 1.08 J cm-2 at 1064 nm. These advantages make SQDs-PVK one of the promising candidates for a broadband optical limiter in both the near-infrared and visible ranges.

Biosynthesis of gold nanoparticles from Martynia annua aqueous leaves extract, its antioxidant potential and antimicrobial ability against selected wound pathogens

The field of nanotechnology has great potential within the realm of modern nanoscience and technology. Ecologically responsible nanoparticle production requires the careful selection of a solvent that is ecologically acceptable, together with the use of reducing and stabilizing chemicals that are also environmentally beneficial. The utilization of gold nanoparticles has been widely investigated in the fields of separation sciences and illness diagnosis for biological purposes. The objective of this study is to synthesize gold nanoparticles utilizing a Water-based Leaf Extract from the Martynia annua Plant in an ecologically sustainable manner. X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) were employed to analyze the morphological characteristics, stability, and crystalline structure of the produced nanoparticles. The experimental results validate the commencement of the gold ion reduction process by the detected change in color of the reaction mixture to a deep purple colour. Moreover, the synthesis was confirmed by the use of UV–visible spectrometry, within the wavelength region of 584 nm. The zeta potential of the produced nanoparticles is reported to be −31 mV, while the average diameter of the particles is about 21 nm. The synthesized particles exhibit significant antioxidant capacity in comparison to the standard. Further AuNPs shows strong antibacterial potential against Escherichia coli, Staphylococcus aureus, Streptococcus sp, Bacillus subtilis, and Enterococcus sp was 53.94 µg/mL, 78.02 µg/mL, 55.47 µg/mL, 55.83 µg/mL, and 95.24 µg/mL respectively Synthesized particles demonstrate substantial cytotoxicity against A549 human lung cancer cells and it shows the inhibitory concentration at 20 µg/ml. The results indicated a significant decrease in cell viability, which was directly linearly related to the dosage of particles. The Martynia annua plant mediated gold nanoparticles exhibit potent antioxidant and antibacterial properties effectively combating specific wound infections.

Extrusion pre-treatment of cowpea (Vigna unguiculata (L.) Walp.) lignocellulosic sidestream to produce cellulose fibres.

Various agricultural sidestreams have been demonstrated as feedstock to produce cellulose. To the best of our knowledge, there is no research work on the potential of agricultural sidestream from cowpea (Vigna unguiculata (L.) Walp.), a neglected and underutilised crop to produce cellulose fibres. Conventional methods to produce cellulose consume large amounts of chemicals (NaOH) and produce a high amount of effluent waste. Herein, we investigated extrusion pre-treatment without and with an alkali followed by bleaching as an alternative method to conventional alkaline pre-treatment followed by bleaching to produce cellulose fibres from cowpea sidestream. Cellulose extracted by extrusion without and with mild alkali followed by bleaching consumed about 20 times less NaOH compared to the conventional method and produced less effluent waste. Extrusion with mild alkali followed by bleaching resulted in higher cellulose yield, purity, and crystallinity compared to extrusion without an alkali followed by bleaching. However, the conventional method resulted in higher cellulose yield, purity and crystallinity compared to extrusion pre-treatment followed by bleaching. Scanning electron microscopy revealed that micro-sized cellulose fibres with an average diameter of 10-15 μm were extracted using both methods. Notably, cellulose fibres extracted using extrusion pre-treatment were shorter than those extracted using the conventional method. Extrusion pre-treatment is a promising continuous alternative to alkaline pre-treatment to produce micro-sized cellulose fibres from low-value, underutilised cowpea lignocellulosic sidestream, for potential use as a filler in composite plastics. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.