Maximum Zone Research Articles

The Green Solution: In-Vitro and In-Silico Screening of Fagonia cretica and Berberis lyceum Phytochemicals against Haemophilus influenzae

Haemophilus influenzae (family Pasteurellaceae) is a coccobacillus, which is a non-spore-forming, non-motile, and non-acid-fast Gram-negative bacteria, present in upper respiratory tract causing epiglottitis, chronic bronchitis, meningitis, sinusitis, and community-acquired pneumonia. H. influenzae is resistant to certain antibiotics; novel drug discoveries are needed. In the present study, B. lyceum and F. cretica plant phytochemicals were tested in vitro against H. influenzae. Zones of inhibition were measured after the crude extract was tested using a well diffusion method against H. influenzae cultured on chocolate agar. Methanolic crude extract from B. lyceum showed a maximum zone of inhibition (32 mm) followed by ethanolic extract (30 mm). Similarly, methanolic extract from F. cretica showed maximum zone of inhibition (29 mm) followed by ethanolic extract (27.5 mm). Cytotoxic factor outer membrane protein (OMP) from H. influenzae was docked with the previously identified phytochemicals of these plants. In silico analysis shows that phytic acid from these plants is the most potent inhibitor of outer membrane protein (P6) followed by sindamine and karakuramine. The present study recommends that B. lyceum phytochemicals can be synergistically used as a potential drug against H. influenzae.

Bioactive compound from marine seagrass Streptomyces argenteolus TMA13: combatting fish pathogens with time-kill kinetics and live-dead cell imaging.

Actinobacteria, pervasive in aquatic and terrestrial environments, exhibit a filamentous morphology, possess DNA with a specific G + C content and production of numerous secondary metabolites. This study, focused on actinobacteria isolated from marine seagrass, investigating their antibacterial activity against fish pathogens. Among 28 isolates, Streptomyces argenteolus TMA13 displayed the maximum zone of inhibition against fish pathogens-Aeromonas hydrophila (10mm), Aeromonas caviae (22mm), Edwardsiella tarda (17mm), Vibrio harveyi (22mm) and Vibrio anguillarum (12mm) using the agar plug method. Optimization of this potent strain involved with various factors, including pH, temperature, carbon source and salt condition to enhance both yield production and antibacterial efficacy. In anti-biofilm assay shows the maximum percentage of inhibition while increasing concentration of TMA13 extract. Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC) assays with TMA13 crude extract demonstrated potent activity against fish pathogens at remarkably low concentrations. Time-kill kinetics assay showcased growth curve variations over different time intervals for all fish pathogens treated with a 100µg/ml concentration of crude extract, indicating a decline in cells viability and progression into the death phase. Additionally, fluorescence microscopic visualization of bacterial cells exposed to the extracts emitting green and red fluorescence, enabling live-dead cell differentiation was also studied. Further characterization of the crude extract through GC-MS and FT-IR analyses performed and identified secondary metabolites with functional groups exhibiting significant antibacterial activity. This study elucidates the capacity of Streptomyces argenteolus TMA13 to enhance the production of antibiotic compounds effective against fish pathogens.

A new magneto-plastic coupling model for residual stress description in ferromagnetic materials

The paper addresses the topic of residual stress in magnetic behaviour of the ferromagnetic materials. Carbon steel parts are submitted to several stress loads and the magnetic behaviour is collected at several operating points. After stress load, the hysteresis data are measured and illustrate a complex behaviour in hysteresis morphology where a big belly is observed near coercive field and a short neck in maximum induction zone. In order to describe the B-H curves, a modified Arctangent model is proposed. A comparison between experiments and model signals show a very good accuracy.

In vivo toxicity evaluation and antibacterial assessment of vanadium doped Bi2Se3 synthesized by cost effective method

Bismuth selenide-based nanomaterials are introduced as theranostic agents, primarily enhancing their antimicrobial, anti-cancerous, antitumor, and antioxidant properties. Pure Bi2Se3 and V doped Bi2Se3 with V = 0.07 g, 0.12 g, and 0.15 g were synthesized by using Sol-gel Technique. X-ray Diffraction (XRD) patterns demonstrated that the manufactured samples were crystalline in nature having rhombohedral structure. The average crystallite sizes of VxBi2-xS3 were calculated by Scherrer formula in the range (24.9–11.0 nm). The average crystallite size reduced as doping concentrations increased (0–0.15 g). The FTIR (Fourier transform infrared) spectra confirms that the peaks corresponds to 900–600 cm−1 indicates Bi–Se bond stretching, whereas vibrations exhibit peaks between 704 cm−1 - 830 cm−1 in doped samples correspond to V–O bond. UV–Visible analysis shows that the band gap of doped Bi2Se3 increased from (2.57 eV–2.90 eV) having standard error 0.02, 0.01, 0.02, and 0.02 respectively as the concentrations of doping increased (0.0–0.15 g), respectively. SEM (Scanning electron microscopy) study of pure Bi2Se3 showed nanosized particles, and for doped, a clear change in morphology occurred with the particles tending to agglomerate. EDAX also confirms the purity of synthesized samples. XPS analysis confirms the presence of Bi, Se and Vanadium along with chemisorbed oxygen. Antibacterial potential of synthesized samples was analyzed against Pseudomonas, Escherichia coli and cocci bacteria, which showed that the vanadium doped bismuth selenide has greater zone of inhibition than undoped bismuth selenide. Pseudomonas shows more ZOI (Zone of Inhibition) than E.coli and cocci. The maximum inhibition zone was 25 mm against Pseudomonas for V0.15Bi1.85Se3. The In-Vivo toxicity experiment was also applied on mice's (Swiss Albino) with a higher dosage of 20 mg per kg of the prepared doped sample. The blood samples were collected and examined after 3rd, 7th, 14th and 21st day of treatment. The entire treatment does not cause any severe damage to mice. An evaluation of a p-value based on hematological and biochemical data was non-significant this ensures that vanadium doped Bi2Se3 nanoparticles are non-toxic and biocompatible. This work proves that V-doped Bi2Se3 is good for further study in many other Applications in the biomedical field, such as photo thermal therapy, imaging etc.

Evaluation of Antimicrobial and Antioxidant Potential of Oxalis corymbosa Extracts.

This work aimed to assess the antioxidant and antimicrobial properties of Oxalis corymbosa extracts. Biochemical analyses were conducted on various plant parts, utilizing enzymatic and non-enzymatic assays. Parameters such as total soluble protein, chlorophyll, and carotenoid contents were also evaluated to elucidate the role of bioactive chemical compounds. The antimicrobial screening of extracts was performed against the bacterial and fungal strains Escherichia coli, Staphylococcus aureus, and Candida albicans, respectively. Results indicated that chlorophyll a, chlorophyll b, total chlorophyll, carotenoid content, anthocyanin content, catalase, peroxidase, and superoxide dismutase were most abundant in the O. corymbosa leaves. Moreover, total ascorbate peroxidase content, total phenolic content, and total flavonoid content were found to be higher in the roots compared to other parts. High-performance liquid chromatography analysis identified chlorogenic acid as the major component, followed by gallic acid, caffeic acid, quercetin, and salicylic acid. Regarding antibacterial potential, each extract exhibited significant activity, with methanolic and ethyl acetate extracts demonstrating the maximum inhibition zone against S. aureus and E. coli, respectively. These findings highlight the substantial antioxidant and antibacterial potential of different parts of O. corymbosa, suggesting their promising applications as ingredients in various nutraceutical products.

In-Vitro Management of Erwinia amylovora caused by Fire Blight of Apple with Synthetic Chemicals

Apple (Malus pomila L) belongs to family Rosacea and it is an edible fruit; mostly utilized by different age groups. Apple trees are grown worldwide. It is considered an important fruit in the temperate region of Balochistan, Pakistan. Fire blight is caused by the pathogen Erwinia amylovora the most damaging disease of apple and other pomes orchards in the world. The aim of the present study was conducted to record the incidence of the disease and management through the use of chemicals. For this purpose, survey was conducted for disease samples from the various districts of Balochistan Viz., Quetta, Ziarat, Killa Saifullah and Kalat. Among all the districts Ziarat was found to be most severe by pathogen with 20% incidence followed by Quetta having 18.67%, Kalat14.31% and Killa Saifullah 13.44% incidence, and different chemicals, i.e. Streptomycin, Tetracycline, Gentamicin, Kasugomycin, Oxytetracycline at different doses were tested against the pathogen and all the chemicals shown great effectiveness against Erwiana amylorora In-vitro conditions. The maximum inhibition zone made by chemical streptomycin with value 15.50 and minimum value of tetracycline with 10.90.and there was no inhibition zone observed in control treatment. All the data was statistically analyzed

Effect of typhoon on suspended sediment concentration, bed erosion and sediment transport in the Yangtze Estuary

Annually 5–6 typhoons strike the Yangtze Estuary (YE) as extreme events. However, their high energy and importance for sediment transportation and geomorphic changes are still not fully understood. In this study, high-resolution observations of wind, wave, flow velocity, and suspended sediment concentration (SSC) at two in-situ stations were carried out during the 2022 Hinnamnor typhoon. Additionally, we simulated the change in SSC, estuarine bed erosion/deposition, and flow and sediment transport with and without a typhoon in the YE using MIKE3 numerical model. The findings revealed that the Hinnamnor typhoon-induced waves increased the SSC of the turbidity maximum zone (TMZ) by a factor of 5.6 times (maximum is 2.8 kg/m3). The TMZ area also extended by 2.68 times (maximum is 7880km2, 70.4% of YE) in the YE. Moreover, the typhoon caused a dramatic change in sediment transport and bed erosion/deposition in the YE. First, in the delta front area where the mean water depth is >5 m, the typhoon significantly increased the southward flux of residual flow and sediment, causing sediment transport into Hangzhou Bay to abruptly increase 26.3 times (increase of 52 million tons, accounting for 1/3 of the present annual flux of the Yangtze River (150 million tons)) during a single spring-neap period. The net erosional area and volume extended to 6770km2 (60.4% of YE) and 91.18 × 106 m3. Second, in the delta shoals (where the mean water depth is <5 m, including east Chongming Shoal, Hengsha Shoal, Jiuduansha Shoal, and east-south Nanhui Shoal), residual flow and sediment flux decreased northward from the typhoon and resulted in the erosion of the shoal. Third, in channels with trumpet-shaped mouths (North Branch (NB), North Channel (NC) and South Passage (SP), except for North Passage (NP)), the upward flux of residual flow and sediment increased due to the typhoon, resulting in bed deposition in these channels (NB, NC and SP). This study highlights the important influence of typhoons on flow and sediment transport and bed erosion in estuarine areas.

Calotropis Gigantea Latex-Derived Zinc Oxide Nanoparticles: Biosynthesis, Characterization, and Biofunctional Applications

Latex of C. gigantea was used to synthesize zinc oxide nanoparticles (ZnO NPs) by the green chemistry approach. The crystalline size, shape, and purity of as-synthesized ZnO NPs were characterized through scanning electron microscopy with energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction analysis, and Fourier-transform infrared spectroscopy techniques. Crystalline, spherical ZnO NPs with an average size of 21.8 nm were formed. In addition, the biological properties of the ZnO NPs, such as antioxidant and antibacterial activity, were evaluated by 2,2-diphenyl-1-picrylhydrazyl assay and the agar well-diffusion method. The highest free radical scavenging activities of 83.11 ± 1.89 % were observed at a concentration of 350 μg/mL of C. gigantea latex-mediated ZnO NPs. The latex in the C. gigantea latex-mediated ZnO NPs inhibited the growth of pathogenic bacteria. The maximum zone of inhibition was found in P. aeruginosa and S. aureus. C. gigantea latex-mediated ZnO NPs have significant biocompatibility and broad-spectrum antibacterial properties against wound-causing bacteria and, therefore, can be suggested for use in the formulation of novel creams or gels for healing applications.

Comparable Antibacterial Effects of Silver and Iron Oxide Nanoparticles on Urinary Calculi Obtained After Percutaneous Nephrolithotomy

Background: In recent years, science and industry have focused on preparing nanoparticles (NPs). Due to the resistance of bacteria to antibiotics, there is an overwhelming need to find effective antimicrobials with fewer side effects. Objectives: The aim of this study was to synthesize silver and iron oxide NPs and investigate their antimicrobial effects on bacteria isolated from urinary stones. Methods: Cases of urolithiasis from 45 patients with staghorn stones, extracted through percutaneous nephrolithotomy (PCNL), were included in the study. Urinary stone cultures were performed, and the isolation and identification of bacteria were done using standard microbiological techniques. Silver and iron oxide NPs were synthesized, and the minimum bactericidal concentration (MBC) and minimum inhibitory concentration (MIC) were evaluated for the isolates. Results: Seventeen (60.7%) out of 28 positive cultured cases of the isolated bacteria were gram-negative, and 11 (39.3%) were gram-positive. The most abundant isolated bacterium was Escherichia coli, with 13 cases (46.4%). The antibacterial effects of silver and iron oxide NPs revealed that the maximum inhibitory zone for Ag NPs at 1000 ppm was 23 mm, and for Fe3O4 NPs, it was 18.5 mm. The MIC was 180 µg/mL for Ag and 250 µg/mL for Fe3O4. The MBC was 228 µg/mL for Ag and 300 µg/mL for Fe3O4. Conclusions: Nanoparticles exhibited antibacterial effects on the bacteria studied in a concentration-dependent manner. Ag NPs showed a more pronounced bactericidal effect than Fe3O4 NPs. As a result, these two NPs demonstrated effective antibacterial activity against both gram-positive and gram-negative bacteria.

Green synthesis and characterization of silver nanoparticles from Nigella sativa L seeds and It’s against human pathogenic bacteria and fungi

The green synthesis of silver nanoparticles (SNPs) is the most economical, rapid, facile, and eco-friendly technique. In this study, pathogenic bacteria from human stool were identified, and the antibacterial potency of Nigella sativa L. seed extracts containing SNPs was assessed. The identification of the isolated pathogenic bacteria was achieved through the analysis of their 16 S rDNA sequences. The characterization of SNPs was done by ultraviolet–visible spectroscopy (UV–VIS spectroscopy), scanning electron microscope (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Six pathogenic bacteria were isolated from human stool and isolated bacteria were identified by 16 S rDNA sequencing analysis. SNPs were found in the size range of 30–60 nm and showed good antibacterial and antifungal activity. The maximum zone of inhibition was found against A. spanius at 32.0±0.8 nm. Achromobacter spanius, Pseudomonas geniculate, and Enterobacter asburiae WL115 were extremely sensitive to heated treated nanoparticles at 100 μg ml−1. In the current work, N. sativa L. was investigated because it produced SNPs effectively, may be used as a safe, affordable agent, and may have antibacterial and antifungal properties. The potential biological uses of SNPs will be encouraged by these discoveries, which will drive future research.

Biosynthesis, Structural, Spectroscopic, Photoluminescence, and Antifungal Activity of Ni-doped CeO2 Nanoparticles.

Pedalium Murex leaf extract was used in this study to create Nickel-doped Cerium oxide (Ni-CeO2) nanoparticles at 3mol% and 5mol% molar concentrations. The biosynthesized process was applied for the fabrication of Ni-CeO2 NPs. The X-ray diffraction method was used to identify their crystal structure. The XRD measurements showed that the Ni-CeO2 NPs crystallized into the face-centred cubic system. Fourier transform infrared spectral study was applied to explore the molecular vibrations and chemical bonding. The surface texture and chemical ingredients of Ni-CeO2 NPs were studied using field-emission scanning electron microscopy and energy-dispersive X-ray analysis. The EDX mapping spectra illustrate the uniform dispersal of Ce, Ni, and O atoms over the sample's surface. X-ray photoelectron spectroscopy (XPS) was conducted to confirm the chemical state of the Ni-CeO2 NPs. UV-Vis spectrum study was performed to ascertain the photon absorption, bandgap, and Urbach edge of Ni-CeO2 NPs. Photoluminescence (PL) research has been used to study the light-emitting characteristic of Ni-CeO2 NPs. The emissive intensity transition corresponding to Ni-CeO2 NPs was found to increase with the dopant level. The CIE 1931 chromaticity map was plotted to find the aptness of the samples for optical uses.The antifungal ability of Ni-CeO2 NPs was evaluated against the fungi candida albicans and candida krusein with the agar well-diffusion process. The fungicidal activity of the 3mol% Ni doped CeO2 nanoparticles has shown a maximum zone of inhibition. The experimental findings illustrate the utility of Ni-CeO2 NPs for optical and antifungal applications.

Evaluation of antimicrobial and anticancer efficacy of silver nanoparticles phytofabricated by Nyctanthes arbor-tristis L. leaf extract

Nyctanthes arbor-tristis L. (Oleaceae), commonly known as harsingar, is a plant with potential medicinal properties. The plant was used in traditional folk medicine and as a pharmacological activity. The present study reports a rapid and eco-accommodating technique to synthesize silver nanoparticles AgNPs with low cost and with no need to heat, using aqueous extracts of N. arbor-tristis L. Phytochemical analysis was conducted to detect the existence of alkaloids, flavonoids, saturated sugar, saponins, glycosides, steroids, tannins, terpenoids, and proteins in the plant. A color change observed in the test confirmed the synthesis of AgNPs. SEM, XRD, EDX, FTIR, and UV – Visible spectrophotometer (DLS) were used to characterize the synthesized AgNPs. The antibacterial potential of AgNPs was further tested against different bacterial strains such as Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Staphylococcus aureus and Klebsiella pneumonia displayed by finding the maximum zone of inhibition observed against S. typhi of 24.6 mm, S. aureus 21.6±0.57 mm, P. aeruginosa 19 mm, K. pneumonia 17 mm and E. coli 15.3±0.57 mm. Furthermore, the synthesized AgNPs were also exhibited as anticancer properties against MDA-231 cell line Human Breast cancer cell line which was determined dose dependent manner and their concentration of 2.5 to 30 μg/mL respectively, and noted the inhibitory range at 30 μg/mL of its concentration, which was further tested in high inhibitory effect on their leaf extract high concentration in cytotoxic, bactericidal experiments.

Keratoconus and Corneal Ectasia with Relatively Low Keratometry.

The study aims to demonstrate and estimate the prevalence of clinical corneal ectasia and keratoconus (KC) in patients with relatively low keratometry (low-K KC). In a retrospective, analytical, and non-interventionist study, one eye was randomly selected from 1054 patients from the original Tomographic Biomechanical Index (TBIv1) study and the external validation (from Rio de Janeiro, Brazil, and Milan, Italy clinics). Patients were stratified into three groups. Group1 included 736 normal patients, and groups 2 and 3 included 318 patients with clinical KC in both eyes, divided into low-K KC (90 patients) and high-K KC (228 patients), respectively. All patients underwent a comprehensive ophthalmological evaluation along with Pentacam and Corvis ST (Oculus, Wetzlar, Germany) examinations. Cases with maximum mean zone 3mm keratometry (Kmax zone mean 3mm) lower than 47.6diopters (D) were considered as low-keratometry keratoconus, and cases with Kmax zone mean 3mm higher than 47.6D were regarded as high-keratometry keratoconus. Ninety (28.30%) of the 318 KC group presented ectasia with low-keratometric values (low-Kmax). The average age in the normal group was 39.28years (range 6.99-90.12), in the low-Kmax KC group it was 37.49 (range 13.35-78.45), and in the high-Kmax KC group it was 34.22years (range 12.7-80.34). Mean and SD values and median (range), respectively, of some corneal tomographic and biomechanical parameters evaluated from the low-Kmax KC group were as follows: Belin-Ambrósio enhanced ectasia display (BAD-D) 3.79 ± 1.62 and 3.66 (0.83-9.73); Pentacam random forest index (PRFI) 0.78 ± 0.25 and 0.91 (0.05-1); corneal biomechanical index (CBI) 0.58 ± 0.43 and 0.75 (0-1); TBI 0.93 ± 0.17 and 1 (0.35-1); and stiffness parameter at A1 (SP-A1) 86.16 ± 19.62 and 86.05 (42.94-141.66). Relatively low keratometry, with a Kmax lower than 47.6D, can occur in up to 28.30% of clinical keratoconus. These cases have a less severe presentation of the disease. Future studies involving larger populations and prospective designs are necessary to confirm the prevalence of keratoconus with low keratometry and define prognostic factors in such cases.

Assessment of Wavefront Aberrations in Children with Myopia Against the Background of Ocular Surface Disorders in Combination with Computer Vision Syndrome Digital and Eye Strain

Purpose: to assess the state of the wavefront in children with myopia, who have various manifestations of digital eye strain and symptoms of ocular surface disorders, and to evaluate the diagnostic significance of wavefront criteria for assessing the state of the ocular surface.Patients and methods. The study involved 76 children (152 eyes) with myopia aged 8 to 18 years who used gadgets and computers for more than 2 hours a day. All patients used glasses as a method of optical correction and were constantly worn. The patients were divided into 2 groups: 1st with symptoms of ocular surface disorder, 2nd — comparison group. Subjective signs were studied using the online questionnaire “State of the ocular surface”. Using the “Keratograph 5M Oculus” the following parameters were assessed: non­invasive tear film breakup time (NTBR), including the first tear film breakup time, average tear film breakup time, breakup time gradient and maximum tear film breakup zone, the same device was used to perform infrared meibography and study of the lipid layer of the tear film. All patients underwent wavefront aberrometry in a darkened room without cycloplegia.Results. It was found that in the group of patients with the presence of subjective phenomena of disturbance of the state of the ocular surface, identified using the online questionnaire “State of the ocular surface”, rotor aberrations were statistically significantly higher than in the comparison group. At the same time, the indicators of higher­order corneal aberrations have comparable values. Correlation analysis between indicators of the state of the ocular surface and parameters of the wavefront in the group of children with disturbances of the state of the ocular surface showed that a higher level of corneal aberrations corresponds to a higher number of points on the questionnaire of disturbances of the ocular surface and the state of visual comfort, in turn, when comparing data on non­invasive tear film breakup time, a negative correlation was established, which means that with a higher number of points on the questionnaire, and therefore, with a more significant degree of impairment of the ocular surface, the tear film breakup time was shorter.Conclusion. The structure of the wavefront in children with myopia against the background of a disorder of the ocular surface in combination with CVS and digital eye strain is significantly different from the structure of the wavefront in the comparison group.

Investigation of bioactive constituents and evaluation of in vitro bioactivities of different Setaria glauca extracts

The aim of this research was to look at the various biological potentials and phytochemical components of S. glauca. Utilizing FT-IR spectroscopy, different functional groups were identified. Tests for total reducing power (TRP), total antioxidant capacity (TAC), and DPPH were employed to assess the antioxidant qualities of a specific medicinal plant. The antibacterial activity of five different strains of bacteria were assessed using the disc diffusion method. Laboratory-cultured nauplii were killed in the brine shrimp lethality experiment to assess the cytotoxic capability. Statistical software version 8.1 was utilized to conduct an analysis of variance (ANOVA), with each experiment being repeated three times. In S. glauca, ten distinct functional groups were found. TAC (SGM = 20.07 AAE/g) and DPPH scavenging capacity (IC50 = 28.38 µg/mL) were noted in the methanol extract of S. glauca (SGM) as well as the total reducing power (TRP) of 62.87 GAE/g was found in SGM. The antibacterial activity was evaluated using several types of bacteria. The maximum zone of inhibition (MI) against P. aeruginosa (ATCC) was found in SGC (12 ± 1.0 mm mean value). The chloroform extract of S. glauca (SGC) exhibited the highest cytotoxic potential, with an LC50 of 31.12 µg/mL. The present investigation examined the remarkable biological capabilities exhibited by S. glauca. Future research in therapeutic development could potentially be enhanced by the isolation and characterization of these bioactive compounds through further research.

Optical, structural and antibacterial properties of phase heterostructured Fe2O3–CuO–CuFe2O4 nanocomposite

The synthesis of the Fe2O3–CuO–CuFe2O4 nanocomposite was effectively achieved through the sol–gel technique, utilizing ethanol as a reactive fuel. Investigation of the nanocomposite’s structure via X-ray Diffraction confirmed the coexistence of Fe2O3, CuO, and CuFe2O4 phases within the material. The Scherrer equation was applied to determine an average crystallite size ranging from 60 to 95 nm. UV–visible spectroscopy studies suggested the material possesses an approximate energy bandgap of 4 eV. Scanning Electron Microscopy provided insights into the nanocomposite’s surface morphology, which exhibited a porous and heterogeneous aggregation of particles in various sizes and shapes. When tested for antibacterial efficacy, the nanocomposite exhibited activity against gram-positive S. aureus with a maximum zone of inhibition (ZOI) measuring 9 mm at the highest concentration, whereas no inhibitory effect was detected against gram-negative E.coli.

CHARACTERISTICS OF MUTUAL ACTIVATION OF AN INTERGEL SYSTEM BASED ON HYDROGEL POLYMETHACRYL ACID AND POLY-4-VINYL PYRIDINE

The electrochemical properties of mutual activation of polymer networks as a result of remote interaction in an intergel system have been studied. An intergel system consisting of hydrogels of rare crosslinked polymethacrylic acid (hPMAA) and poly-4-vinylpyridine (hP4VP) was chosen as the object of study [1,2]. The purpose of the work is to study the mutual activation features of the intergel system of rare crosslinked hPMAA: hP4VP. The obtained results as the contact time of hydrogels with water increased, zones of maximum and minimum conductivity were observed at the highest points of initial conductivity for different ratios of hPMAA:hP4VP hydrogel systems. In the 6:0 ratio of hPMAA hydrogel, the specific conductivity of the aqueous medium reached its maximum value after one day, and the pH value of the medium decreased relatively to about 4.95. The swelling degree of hPMAA hydrogel was constant at 6:0 different time intervals. In this system, only one polymer, namely hPMAA showed that the hydrogel's water absorption capacity was limited. In the 5:1 ratio of the intergel system, the specific conductivity of the medium reached a high value, and the pH value decreased in the 5:1 ratio. After 2.5 hours of study, a decrease in the conductivity of the aqueous medium was observed at 4:2 hydrogel ratio. After 6 hours, the highest degree of swelling was maintained at 1:5 ratio. In the presence of hP4VP hydrogel at a ratio of 0:6, the pH of the medium increased from 5 to a maximum value of 6.6 within 24 hours. Conclusion. The electrochemical properties of hPMAA:hP4VP hydrogel system were studied by remote interaction. Based on the systematic work, we synthesized the required acidic hydrogel hPMAA:hP4VP and carried out various studies on their properties. To create an intergel system, the obtained hydrogels in seven different proportions were made into an intergel system and their interactions were studied using various physicochemical methods. As a result of the study, the remote interaction of hydrogels in the intergel system leads to conformational changes in their intercellular bonds which undergo additional swelling. As a result of mutual activation, the hydrogels move to a highly ionized state.

Biogenic silver nanoparticles from fungal sources: Synthesis, characterization, and antifungal potential

Nano-biotechnology is quickly developing as an important field of modern research, generating the most promising applications in medicine and agriculture. Biosynthesis of silver nanoparticles using biogenic or green approach provide ecofriendly, clean and effective way out for the synthesis of nanoparticles. The main aim of the study was to synthesize silver nanoparticles (AgNPs) from Aspergillus niger, Aspergillus flavus and Pencillium chrysogenum using a green approach and to test the antifungal activity of these synthesized AgNPs against a variety of pathogenic fungi. The characterization of samples was done by using UV–visible spectroscopy, SEM (scanning electron microscopy), FTIR (Fourier transmission infrared spectroscopy), and XRD (X-ray diffractometry). The investigation confirmed the creation of AgNPs by the fungi Aspergillus niger, Aspergillus flavus and Pencillium chrysogenum, as evidenced by prominent plasmon absorbance bands at 420 and 450 nm.The biosynthesized AgNPs were 80–100 nm in size, asymmetrical in shape and became spherical to sub-spherical when aggregated. Agar well diffusion method was performed to evaluate the antifungal activity of AgNPs against various plant pathogenic fungi. An efficient and strong antifungal activity was shown by these biosynthesized nanoparticles against serious plant pathogenic fungi, viz. Aspergillus terreus, Fusarium oxysporum, Penicillium citrinum, Rhizopus stolonifer and Mucor mucedo. The biosynthesized AgNPs at various concentrations caused significant zone of inhibition in the test fungal pathogens. Silver nanoparticles (AgNPs) biosynthesized from Aspergillus niger at highest concentrations showed maximum zone of inhibition against Penicillium citrinum (19.33 ± 0.57 mm) followed by Rhizopus stolonifer (17.66 ± 0.57), Aspergillus terreus (16.33 ± 1.54 mm), Fusarium oxysporum (14.00 ± 1.00 mm) and Mucor mucedo (13.33 ± 1.15 mm) respectively. Therefore, the findings clearly indicate that silver nanoparticles could play a significant role in managing diverse plant diseases caused by fungi.

Evaluation of Antimicrobial Effect of Ginger, Apple Cider Vinegar against Streptococcus Mutans, Enterococcus Faecalis and Candida Albicans.

Oral infections are most frequently caused by three oral microorganisms: Streptococcus mutans (S. mutans), Enterococcus faecalis (E. faecalis), and Candida albicans (C. albicans). To evaluate antimicrobial potential of 10% ginger extract (GE) and apple vinegar against S. Mutans, E. faecalis, and C. albicans. The GE and apple cider vinegar (ACV) were tested for microbiological evaluation to identify the inhibitory zone using the agar disk diffusion test against S. mutans, C. albicans, and E. faecalis. The 10% ethanolic GE and ACV showed a maximum zone of inhibition zone against S. mutans, E. Faecalis, and C. albicans. The intragroup comparison was insignificant. Apple vinegar and 10% ethanolic GE were shown to have good antimicrobial properties against all three tested pathogens.

Plastic zone characteristics and rapid stability evaluation indexes of circular tunnels subjected to non-hydrostatic stress: A novel complex variable solution incorporating 3D rock mass strength

The morphological characteristics and distribution range of the plastic zone around tunnels, influenced by the true three-dimensional high geostress environment in deep engineering, constitute fundamental reference data for both tunnel design and the control of surrounding rock stability. Based on the GZZ three-dimensional rock mass strength criteria and the complex variable method, a novel semi-analytical method for solving the plastic zone of a circular tunnel subjected to non-hydrostatic stress is presented. The conformal mapping is employed to intricately transform the complex boundaries of plastic zones characterized by diverse shapes onto the unit circle boundary within the image plane. This framework proves invaluable for the precise analytical process of the complex plastic zone morphology and the plastic influence range within the surrounding rock under complex stress conditions. In contrast to traditional analytical methods, the efficacy and versatility of our proposed approach are substantiated. Notably, it demonstrates unique advantages, particularly in the context of non-hydrostatic stress fields and varied rock mass parameters, with respect to predicting both surrounding rock stability and plastic zone morphology. Through the analysis of numerous cases, the study reveals the systematic patterns of influence that in-situ stress and surrounding rock characteristic parameters have on the shape and maximum depth of the plastic zone. The results indicate that (1) there are notable disparities in the morphology and extent of the plastic zone between the GZZ and GHB criteria; (2) the transition of the plastic zone in surrounding rock from U-shaped to V-shaped is significantly influenced by the geostress-to-strength ratio Kσ; (3) there is a notable linear correlation observed between the maximum plastic zone thickness rmax and both Kσ and the stress concentration factor KSCF, importantly, this correlation is independent of far-field stress and the brittleness characteristics of the surrounding rock. These findings provide a novel discriminative method for the rapid analysis of surrounding rock stability in deep circular tunnels.