Agar Disc Diffusion Method Research Articles

Biological Activity of Essential Oil from Two Aromatic Species on the in vitro Control of Colletotrichum gloeosporioides (Penz.) Penz. & Sacc.

Objective: Essential oils (EO) from aromatic and medicinal plants (AMP) are considered a viable alternative for controlling phytopathogenic fungi of agronomic importance. This study evaluated the antifungal activity of thyme (Thymus vulgaris L.) and rue (Ruta graveolens L.) essential oils against Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. Design/Methodology/Approach: The antifungal activity was assessed using the agar disk diffusion method, with concentrations ranging from 10% to 100% of each EO. The phytochemical composition was analyzed using GC-MS. Morphological observations were conducted with a scanning electron microscope (SEM). Results: Significant antifungal activity was observed at concentrations of 50-100% of thyme EO. Rue EO exhibited a fungistatic effect for up to six days. Phytochemical analysis identified carvacrol (35.95%) and p-cymene (41.18%) as the major components in thyme EO, and 2-nonanone (24.24%) and 2-undecanone (68.69%) in rue EO. Findings/conclusions: The evaluated EOs significantly impacted fungal morphology at 60% concentration. The strong antifungal activity of thyme EO against C. gloeosporioides suggests its potential as an eco-friendly control alternative.

Antimicrobial effects of eugenol-based micro- vs. nano-emulsions: Evaluation of shelf-life enhancement in Sikhye

This study investigated the antibacterial properties of micro-emulsions (MEs) and nano-emulsions (NEs) containing eugenol and rice bran oil to enhance the shelf life of Sikhye, a traditional Korean rice beverage. The emulsions were evaluated using the agar disk diffusion method and minimum inhibitory concentration (MIC) tests against Escherichia coli, Bacillus cereus, and Staphylococcus aureus. The results demonstrated that MEs exhibited larger inhibition zones and lower MIC values than NEs, indicating superior antibacterial activity. The application of these emulsions in Sikhye revealed that a higher eugenol content and larger droplet size effectively inhibited bacterial growth. The study also found that, while rice bran oil contributed to physical stability, it did not enhance the antimicrobial effect and, in some cases, promoted bacterial growth. Overall, these findings suggest that eugenol-rich MEs could serve as effective natural preservatives, improving the safety and shelf life of Sikhye and potentially other food products.

Synthesis and application of WO3/PVA nano composite for antibacterial and thermal insulation

Abstract Insulation of glass material is very important for sustainable environment in this real world without compromising its primary function. The aim of this research is to provide robust solution by synthesis the Nano Tungsten trioxide particles via the chemical precipitation method. Developed WO3 NPs Characterized by using x-ray diffraction for; crystal structure, compound composition, and average crystalline size. Scanning Electron Microscopy (SEM) employed to analyze the shape and dimensions of the WO3 NPs. Explored the potential thermal insulation and antibacterial attributes by coating 1%, 3%, 5% and 7% concentration of synthesized WO3 NPs in polyvinyl alcohol onto a sodium silicate glass substrate (4 × 4 inches; 2 mm thickness) by using 50 μm doctor blade. WO3/PVA solution showed the antibacterial properties measure by agar disc diffusion method on gram positive and negative bacterial culture S. coli and E. bacterial culture and the obtained results after incubation were showing very minor zone of incubation as compare to previous studies. Thermal insulation of coated glass samples were increased with % of WO3 NPs concentration in PVA and validate by significant coefficient of determination (R2 = 0.985).

Synthesis, Antimicrobial and Antioxidant Activity with in silico ADMET Prediction, Molecular Docking and Dynamics Studies of Carbazole Ring Containing Thiazole Schiff Bases

AbstractTwelve thiazole hybrids (2 a–2 l) were synthesized in this study incorporating with Schiff base and carbazole scaffolds and characterized by spectral analyses. Antimicrobial activity and antioxidant potency were investigated by agar disc diffusion method and DPPH free radical scavenging assays where trimethyldihydrothiazole 2 c had revealed its higher efficacy in both biological studies. It had displayed IC50 of 25.55±0.40 μg/mL which is higher than the standard ascorbic acid (IC50=41.31±1.83 μg/mL) as well as dihydrothiazoylchromenone 2 e showed promising antioxidant activity with IC50 value of 40.82±0.54. The compound 2 c satisfied all the ADME properties and toxicological parameters with maximum drug score value (0.39) among all derivatives. Molecular docking was undertaken for higher bioactive compounds where 2 c revealed its wide range of interactions with different amino acid residues which was also endorsed with the output of molecular dynamics simulation.

Comprehensive analysis of antioxidant and antibacterial activities of water and methanol extracts of Hibiscus flower

This study provides a comprehensive investigation into the antioxidant and antibacterial properties of Hibiscus flower extracts, highlighting their potential for future applications in functional foods. The research addressed key challenges by employing a multi-faceted approach, including four distinct methods for evaluating antioxidant potential: DPPH and FRAP assays, reducing power, and chelating ability of Fe ions. Total phenolic content was quantified using the Folin–Ciocalteu method, while tannins and flavonoids were assessed via vanillin–HCl and aluminum chloride assays. Additional analyses included spectrophotometric measurement of total flavonols and anthocyanins. Antibacterial activity was determined using a modified agar disk diffusion method, with results indicating significant inhibition of Salmonella typhimurium and Staphylococcus aureus by both aqueous and methanolic extracts. Colorimetric analysis revealed a reduction in chroma and hue angles, while FTIR spectroscopy identified key functional groups, such as suberin, lipids, and polysaccharides. Notably, the antioxidant efficacy varied depending on the solvent used, with aqueous extracts showing higher total phenolic content (4325.12 mg GAE/100 g) compared to methanolic extracts (3487.05 mg GAE/100 g). The study concludes that Hibiscus flower extracts, rich in antioxidants like tannins and anthocyanins, possess significant potential for use as natural preservatives and colorants in food products, supporting their role in developing novel functional foods.

Increased incidence of methicillin resistant Staphylococcus aureus and methicillin resistant Staphylococcus epidermidis in the skin and nasal carriage among healthcare workers and inanimate hospital surfaces after the COVID-19 pandemic.

Healthcare workers in hospitals are exposed to infectious diseases that occur in the hospital making them a source of infection for the patients. It is interfaced as cross-contamination agents for MRSA and MR-CoNS, and preventive measures need to be adapted accordingly. The study aimed to assess Methicillin-Resistant Staphylococcus (MRS) on the skin and nasal cavities of healthcare workers (HCWs) and identifying isolates to the species level. Swab samples were cultured on mannitol salt agar (MSA) to obtain MRS and determine their ability to produce coagulase. Their susceptibility to antibiotics were determined by agar screening and disk diffusion methods and further identification was done at the species level. The highest percentage of methicillin resistant coagulase positive Staphylococci (MRCoPS) was reported among skins of male HCWs, (71.4%) were identified as MRSA. The highest levels of methicillin resistant coagulase negative Staphylococci (MRCoNS) were mainly detected in both nasal cavities, (75%) were identified as MRSE. MRSA was reported from doctors (p-value 0.033), whereas the highest incidence of MRSE was obtained from the nurses (p-value 0.048). This study highlighted that incidence of MRSA was mainly detected in doctors and MRCoNS in both nasal cavities. The highest percentage of MRCoNS was recovered from the patients' room followed by the reception table. Moreover, vancomycin is suggested to be highly effective in managing and controlling S. aureus, MRSA- and MRSE related infections.

Ten-year comparison of the efficiency of legal regulations of foodborne pathogens in broilers in Türkiye

Broiler meats are the primary source of foodborne pathogens, such as Campylobacter jejuni and Salmonella spp., and E. coli O157. The illegal use of antibiotics for preventive purposes or the habit of using broad-spectrum antibiotics in farms causes antibiotic resistance in these pathogens. This study compared C. jejuni, Salmonella spp. and E. coli O157 and their antibiotic resistance patterns in broiler meats in 2011-2012 and 2021-2022. The research we conducted in 2011-2012 to observe the effectiveness of the legal regulations enacted in Türkiye in 2014 and 2018 for controlling pathogens and monitoring the use of antibiotics was also repeated with a similar sample set in 2021-2022. The results showed the prevalence of C. jejuni, Salmonella spp., and E. coli O157 in 2011-2012 and 2021-2022 with 68.0%, 30.4%, 0.8% and 10.08%, 7.77%, 0.21%, respectively. The antimicrobial susceptibility tests against gentamicin, streptomycin, erythromycin, ciprofloxacin, enrofloxacin, tetracycline and oxytetracycline were performed by agar disk diffusion method. According to results in 2011-2012, all C. jejuni and Salmonella spp. were resistant to at least one tested antibiotic, with 31.57% Salmonella spp. and 16.47% C. jejuni being multidrug-resistant. In addition, one of the E. coli O157 strains was resistant to one antibiotic, and the other was resistant to two antibiotics. In 2021-2022, 81.3% C. jejuni, 46% Salmonella spp., and only one E. coli O157 were resistant to at least one tested antibiotic. Isolated strains of 8.33% C. jejuni and 21.62% Salmonella spp. were multidrug-resistant. In the past, antibiotics were used for preventative purposes, as indicated by the survey results. Today, it is evident that these rates have decreased to low levels as a result of legal regulations and monitoring.

A comprehensive review on in-vitro methods for anti- microbial activity

Microbes, also referred to as microscopic creatures because of their minuscule size and invisibility to human sight, are single-celled microorganisms. The first microorganism was discovered between 1665 and 1683 by Robert Hooke and Antoni van Leuwenhoek. There are two categories of techniques for examining microbial activity. methods used in vitro and in vivo. Experiments and tests carried out in a laboratory setting, typically without the presence of a living organism, are referred to as in vitro methods. By creating microbial cultures, cell lines, cell cultures, etc., we may do in vitro experiments. Scientists can study biological processes, assess the effects of medications, and understand systems without having to deal with the complexities of a whole organism by employing in vitro techniques. Growing cells outside of the body in a controlled setting for a range of studies is known as cell culture. Tissues are grown and kept in a lab setting for tissue culture. It is essential to research creating anti-infection therapies. To evaluate a substance's antibacterial activity, in vitro methods such as the brothdilution method and discdiffusion method are commonly used. There are different methods available for the testing of antimicrobial activity and the methods are the agar disk diffusion method, Agar well diffusion method, cross streak method, Bioautography, dilution method, Time kill test, ATP bioluminescence etc. Techniques for determining novel antimicrobial agents and testing for antibiotic susceptibility have been employed. Compared to in-vivo procedures, in vitro methods are less costly. To guarantee an accurate experimental approach, these techniques may be the answer.

Comparison of the antibacterial activity of six medicinal plants, sodium hypochlorite, and chlorhexidine against enterococcus faecalis (In vitro study)

Enterococcus faecalis is a gram-positive, facultative anaerobic bacterium recognized for its resistance to various antimicrobial agents. This organism is associated with the failure of endodontic treatments, even when potent antimicrobial irrigants are employed. Numerous medicinal plants have demonstrated antimicrobial properties that could be potentially effective against this bacterium.To evaluate the antibacterial properties of six medicinal plants in comparison to sodium hypochlorite and chlorhexidine against E. faecalis.Antibacterial susceptibility tests against E. faecalis (ATCC 29212) were performed for 200 mg/ml ethanolic extracts of Acacia Senegal, Capparis decidua, Capparis micracantha, Acacia nilotica/ Adansonia, Dobera glabra, and Moringa oleifera by Agar Disc Diffusion method. Chlorhexidine 0.2% and Sodium hypochlorite 1% were used as positive controls, and ethanol 20% as a negative control. The diameters of the inhibition zones were measured. Acacia nilotica/adansonii leaves showed the largest inhibition zone diameter against E. faecalis. It displayed a significantly greater inhibitory effect against E. faecalis than Acacia Senegal (p-value =0.005), Capparis decidua (p-value =0.02), Capparis micracantha branches (p-value =0.000), Dobera glabra leaves (p-value =0.008), and Moringa olifera leaves (p-value =0.000).Acacia nilotica leaves displayed a similar inhibition zone diameter against E. faecalis as chlorhexidine gluconate 0.2%, but it showed no statistical significance. Acacia nilotica leaves (L) and pods (P), as well as Dobera glabra branches (B), displayed a larger inhibition zone diameter against E. faecalis than Sodium hypochlorite 1%, but with no statistical significance. The leaves of Acacia nilotica exhibit the most potent antibacterial properties against E. faecalis when compared to other plants parts. They outperform the antibacterial effectiveness of 1% sodium hypochlorite and demonstrate a similar antibacterial impact to that of 0.2% chlorhexidine. Therefore, Acacia nilotica leaves could serve as an ideal irrigant potentially substituting the chemical options.

Extraction, Characterization, and Encapsulation of Cinnamon Hydrosol Obtained via Microwave-Assisted Hydrodistillation: Analysis of Antioxidant and Antimicrobial Activities

Microwave-assisted hydrodistillation (MAHD) method was employed to extract cinnamon oil and hydrosol (a byproduct). The total polyphenol content (TPC) of the cinnamon hydrosol (CH) was determined using the Folin-Ciocalteu method, and its antioxidant power was assessed through the DPPH radical reduction method. Gas chromatography was utilized to quantify the main bioactive compound (cinnamaldehyde). The disc agar diffusion method was applied to evaluate the inhibition of pathogenic microorganisms. To protect the bioactive compound, an encapsulation method involving cross-linking with calcium alginate was utilized. The capsules were examined using environmental scanning electron microscopy (ESEM). The TPC content was found to be 15.63 ± 0.21 mg gallic acid/g dry matter, and the DPPH radical inhibition rate was 84.26 ± 1.35%. CH exhibited a significant inhibitory effect against Escherichia coli, and a moderate inhibition effect against Shigella flexneri, Salmonella spp., Salmonella typhimurium, and Escherichia coli EPEC. Finally, successful encapsulation of CH was achieved using sodium alginate, resulting in bead sizes ranging between 1.75 and 2.75 mm.

Chemical composition and antimicrobial investigation of the essential oil isolated from Montanoa bipinnatifida (Kunth) K. Koch leaves

Montanoa bipinnatifida is a perennial shrub belonging to family Asteraceae and geographically distributed in Mexico, Central America and Northern South America. This study aimed to investigate the chemical composition of the essential oil isolated from M. bipinnatifida leaves through GC-MS analysis accompanied by in-depth investigation of antimicrobial properties against wide arrays of microbial strains via agar diffusion method and disk diffusion method. The GC-MS analysis of the tested oil revealed presence of sixteen components (∼99.99%), predominated by germacrene D (37.22%), β-caryophyllene (30.73%), α-pinene (4.56%) and β-germacrene (4.48%). The undiluted oil exhibits varying levels of activity against different microbes. The leaf oil showed a significant inhibition against Proteus mirabilis, Staphylococcus aureus, Bacillus subtilis (both vegetative and spores), Mycobacterium phlei, and Candida albicans. However, its activity against Sarcina lutea, Escherichia coli, Klebsiella pneumoniae appears to be less pronounced. Thus, the leaf oil of M. bipinnatifida demonstrates broadspectrum antimicrobial activity and is recommended in the pharmaceutical industry to overcome the current problem related to the microbial resistance to antibiotics. Further experimental studies are warranted to investigate the underlying mechanism of action and the responsible individual components.

Enhancing the antioxidant, antimicrobial resistance, and anticancer potency of plant-mediated SnO2 and Se doped P-SnO2 NPs by Justicia adhatoda: An in vitro approach

In this work, plant-mediated SnO2 NPs were green synthesized using Justicia adhatoda plant leaf extract, and the synthesized SnO2 powder was doped with Se nanorods at various concentrations (10 %, 20 %, and 30 %). The synthesized sample was characterized using XRD, HRSEM, SEM-EDAX, SEM-EDS, TEM, UV–Vis, and FTIR spectra. Furthermore, we investigated the antibacterial activity of P-SnO2 NPs and Se-doped P-SnO2 NPs at various concentrations of selenium (10 %, 20 %, and 30 %) against three gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumonia) and one gram-positive bacteria (Staphylococcus aureus) using the agar disc diffusion method. Furthermore, an antioxidant activity (DPHH) and cytotoxicity study (HepG2) were performed. Morphological analysis was used to identify the P-SnO2 nanoparticle shape as spherical in shape and the Se nanoparticle shape as a nanorod. The TEM image reveals that 30 % of the Se-doped P-SnO2 NPs exhibit an inner core structure. The TEM image used to identify the size of P-SnO2 NPs is 64 nm, and the Se nanorod is 4.06 nm. The 30 % Se-doped P-SnO2 NPs demonstrate good bacterial activity compared to P-SnO2, and 10 % and 20 % Se-doped P-SnO2 nanoparticles. Antioxidant activity: 30 % Se-doped P-SnO2 NPs show an excellent IC50 value compared to others; the IC50 values of 30 % Se-doped P-SnO2 NPs are 33.71 µg/ml. The cytotoxicity of 30 % Se-doped P-SnO2 NPs exhibits an IC50 value of 121 µg/ml against the HepG2 cell line. So, it is very useful for medicinal applications.

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

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

Evaluating the Antibacterial and Anti‐Biofilm Properties of Chitosan Nanoemulsion Containing Euphorbia hebecarpa Plant Extract Against Escherichia coli and Staphylococcus aureus

ABSTRACTThe use of nanoparticles as drug‐carrying systems in medicine has received much attention, and on the other hand, the use of plants with medicinal properties has advantages over synthetic drugs. This study aims to improve the antibacterial and anti‐biofilm properties of Euphorbia hebecarpa plant extract using chitosan nanoparticles. Extraction were performed using the modified maceration and methanol solvent. The agar disc diffusion method was carried out to investigate the antimicrobial effects and MIC at an optical density (OD) of 630 nm. The anti‐biofilm agent's influence was measured at OD 570 nm, and the metabolic activity of bacteria in the damaged biofilm was determined using triphenyl tetrazolium chloride (TTC) staining. The nanoparticles were obtained by following the ionic gelation method and its characteristics were evaluated. Chitosan nanoparticles loaded with plant extract were found to be spherical shape with hydrodynamic diameter of 142 nm, a polydispersity index (PDI) of 0.184, a zeta potential of +28.6 mV. It was determined that the loading capacity (% LC) and encapsulation efficiency (% EE) percentages were 33% and 40%, respectively. The diameter of the inhibition zone in the agar disc diffusion test for both bacteria using nanoparticles loaded with the extract increased compared with control groups. Also, at a concentration of 4 mg/mL of loaded nanoparticles, 49.33% of Escherichia coli biofilm and 62.7% of Staphylococcus aureus biofilm were destroyed. The data obtained from the tests performed in this study show that the use of Euphorbia plant extract in the form of chitosan nanoparticles can have more antimicrobial and anti‐biofilm effects.

Phytochemical Characterization and Synergistic Antibacterial Effects of Colebrookea Oppositifolia Essential Oil as Adjuvants to Modern Antibiotics in Combating Drug Resistance.

The global threat of multi-drug-resistant bacteria has severely limited the options available for effective antibiotics. This study focuses on the antimicrobial activity and phytochemical characterization of C. oppositifolia extracts, aiming to identify novel plant-based therapeutic agents. C. oppositifolia specimens-leaves and inflorescence. Specimens were cleaned, sterilized, dried, and ground into a fine powder. Extracts were obtained using methanol and petroleum ether via a Soxhlet apparatus, followed by fractionation with chloroform, n-butanol, and ethyl acetate. Volatile oil was extracted through hydro distillation using a Clevenger apparatus. Phytochemical analysis was conducted to identify bioactive compounds. Biophysical techniques, including UV-visible spectrophotometry, TLC, HPLC, GC-MS, FTIR, and NMR, were employed for characterization. Antimicrobial activity was tested against S. aureus ATCC25922 and E. coli ATCC25922 using agar well and disc diffusion methods, and synergistic effects were assessed with erythromycin and amoxicillin. Methanol extract exhibited bacteriostatic activity with inhibition zones of 13.0 ± 0.2 mm for both S. aureus and E. coli. Petroleum ether, chloroform, n-butanol, and ethyl acetate fractions showed varying inhibition zones. Erythromycin demonstrated bactericidal activity, which was enhanced synergistically when combined with methanol extract and volatile oil, increasing inhibition zones against S. aureus. Phytochemical analysis identified phenols, flavonoids, tannins, coumarins, alkaloids, terpenoids, saponins, and glycosides. FTIR analysis revealed functional groups such as amines, aldehydes, nitriles, alkenes, and sulfones. GC-MS identified 24 compounds, with α-pinene, caryophyllene, and carene as major components. NMR spectra indicated no complex formation between oils and antibiotics, suggesting the compounds act as synergists. The C. oppositifolia extracts possess significant antimicrobial activity and synergistic potential, particularly against S. aureus. The presence of various bioactive compounds suggests a promising role in developing new plant-based therapeutics.

Magnesium borate-glasses for biomedical application: Physicochemical and in vitro bioactive properties, antibacterial activity and cell viability

Borate bioactive glasses doped with magnesium oxide (MgO) were synthetized by melt-quenching method and evaluated their physicochemical and in vitro bioactive properties. The glasses were characterized by volumetric density, DTA, XRD and FTIR techniques. In vitro bioactivity was evaluated by SBF immersion test. Cytocompatibility tests were performed on RAW-247 murine macrophage cells. Antibacterial activity was evaluated by the agar disk diffusion method. The XRD results confirm the amorphous nature of the glasses. FTIR analysis showed that the MgO addition modifies the glass network, causing changes in the volumetric density, molar volume, and thermal properties. The in vitro bioactivity was confirmed by XRD, FTIR, and SEM-EDS analyses; all samples showed the formation of biological apatites. All samples are non-cytotoxic and presented good antibacterial activity against S. aureus and P. aeruginosa bacteria. Therefore, all samples are good candidates for biomedical applications, mainly in bone regeneration.

Assessing β-Carboline Analogues As Antibiotic Agent Using In Vitro Studies

The mortality rate caused by bacterial diseases and bacterial antimicrobial resistance (AMR) is a significant concern in global public health. There is an urgent demand for new therapeutic agents that not only offer improved efficiency but also entail fewer secondary effects, addressing the challenges posed by the currently available drugs used in clinical practice. In this study, 40 analogues of β-carboline were subjected to solubility tests to determine their solubility. Among them, 22 analogues proved to be soluble and were subsequently tested for in vitro antibacterial activity using the agar disc diffusion method against S. aureus and E. coli to evaluate their effectiveness. The results of the in vitro antibacterial studies revealed that compounds 1h, 7d, and 1l displayed appreciable growth-inhibitory effects against E. coli, while compounds 1a, 1f, 1l, and 1j exhibited appreciable growth-inhibitory effects against S. aureus. Notably, compounds 1j and 1l displayed the highest growth-inhibitory potency against S. aureus and E. coli, respectively, out of the 22 compounds tested. Of all the analogues examined, 1l and 1j demonstrated the most substantial growth-inhibitory effects against E. coli and S. aureus, respectively, underscoring their potential as inhibitors.

Metabolic and Antioxidant Responses of Different Control Methods to the Interaction of Sorghum sudangrass hybrids-Colletotrichum boninense.

Colletotrichum boninense is the main pathogenic fungus causing leaf spot disease in Sorghum sudangrass hybrids, which seriously impairs its quality and yield. In order to find an efficient and green means of control, this study used the agar disk diffusion method to screen for a fungicide with the strongest inhibitory effect on C. boninense from among several bacteria, fungi, and chemicals. Then, the changes in the plant's antioxidant system and metabolic levels after treatment were used to compare the three means of control. The lowest inhibitory concentration of Zalfexam was 10 mg/mL, at which point C. boninense did not grow, and the inhibition rates of Bacillus velezensis (X7) and Trichoderma harzianum were 33.87-51.85% and 77.86-80.56%, respectively. Superoxide dismutase (SOD) and chitinase were up-regulated 2.43 and 1.24 folds in the Trichoderma harzianum group (M group) and SOD activity was up-regulated 2.2 folds in the Bacillus velezensis group (X7 group) compared to the control group (CK group). SOD, peroxidase (POD), and chitinase activities were elevated in the Zalfexam group (HX group). The differential metabolites in different treatment groups were mainly enriched in amino acid metabolism and production, flavonoid production, and lipid metabolism pathways. Compared with the diseased plants (ZB group), the M, X7, HX, and CK groups were co-enriched in the tryptophan metabolic pathway and glutamate-arginine metabolic pathway, and only the CK group showed a down-regulation of the metabolites in the two common pathways, while the metabolites of the common pathways were up-regulated in the M, X7, and HX groups. In addition, the salicylic acid-jasmonic acid pathway and ascorbic acid-glutathione, which were unique to the M group, played an important role in helping Sorghum sudangrass hybrids to acquire systemic resistance against stress. This study fills the gap in the control of Colletotrichum boninene, which causes leaf spot disease in Sorghum sudangrass hybrids. This paper represents the first reported case of biological control for leaf spot disease in Sorghum sudangrass hybrids and provides a reference for the control of leaf spot disease in Sorghum sudangrass hybrids as well as other crops infected with Colletotrichum boninense.

Antibacterial, Mechanical, and Thermal Properties of Ag, ZnO, TiO2 Reinforced PVA Nanocomposite Fibers

AbstractThis study investigated the effects of concentration and electrospinning parameters on the production of poly (vinyl alcohol) (PVA) nanofibers and examined the impact of reinforcing additives like nano‐sized silver (Ag), titanium oxide (TiO2), and zinc oxide (ZnO) on these nanofibers. The PVA concentration was varied between 3 % and 10 % wt./v, while the flow rate was adjusted to 0.5, 1, and 5 ml/h. The optimal conditions for producing PVA nanofibers are a concentration of 10 % wt./v at a flow rate of 0.5 ml/h and an applied voltage of 9 kV, resulting in nanofibers with an average diameter of 502±0.10 nm. PVA nanofibers reinforced with nano‐sized 3 % wt. Ag, TiO2, and ZnO and electrospun at optimum conditions. The morphological properties were determined using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM), and the average fiber diameter was measured with the Image J program. The presence of nanoparticles within the nanofibers was confirmed through Energy Dispersive Spectrometry (EDS) and X‐ray diffraction (XRD). Chemical interactions of functional groups between PVA and ZnO, TiO2, and Ag NPs were analyzed with Fourier Transform Infrared Spectroscopy (FTIR), and thermal behaviors were studied with Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). Among the water absorption, Ag‐reinforced PVA nanofibers showed maximum absorbance. Mechanical properties, evaluated through tensile testing, showed the elastic modulus of the nanocomposite fibers to be 38.07±12.01 MPa for PVA/Ag, 88.98±27.5 MPa for PVA/TiO2, and 30.56±9.77 MPa for PVA/ZnO. The antimicrobial activity of the nanoparticle‐reinforced PVA nanofibers was tested using the agar disc diffusion method. The results showed that both Ag and TiO2 reinforced PVA nanocomposite fibers exhibited significant antimicrobial activity (gram–(Escherichia coli) and gram+(Staphylococcus aureus)), with inhibition zones of 8.48±0.08 cm against E. coli and 9.98±0.47 cm against S. aureus for Ag, and 4.32±0.02 cm against E. coli and 3.56±0.05 cm against S. aureus for TiO2.

Anticandidal effect of cinnamic acid characterized from Cinnamomum cassia bark against the fluconazole resistant strains of Candida.

Candida spp., causes invasive fungal infections, especially in immune-compromised patients and the propensity of antifungal resistance against azole-based drugs need to be addressed. This study is thus aimed to characterize the anticandidal effect of the cinnamic acid extracted from the barks of Cinnamomum cassia. Five species of Fluconazole-resistant Candida sp. were retrieved from the department repertoire. The extraction of CA was performed by three different methods followed by silica gel column chromatography. Eluant was subjected to FTIR and XRD analysis for confirmation. The anticandidal activity of the CA was checked by the agar disc diffusion method and the MIC and MFC were determined. The anti-biofilm effect of CA was assessed using the CLSM technique followed by the biocompatibility check using MTT assay in normal HGF cell lines. CA was best extracted with the hot maceration method using ethanol with a maximum yield of 6.73mg. Purification by column chromatography was achieved using benzene, acetic acid, and water (6:7:3) mobile phase. CA was confirmed by FTIR with absorption peaks and by XDR based on strong intensity. CA was found to possess promising anticandidal activity at 8µg/mL with MIC and MFC values determined as 0.8µg/mL and 0.08µg/mL respectively. Antibiofilm activity by CLSM analysis revealed biofilm inhibition and was biocompatible at 8.5µg/ml concentrations in HGF cell lines until 24h. The study findings conclude that CA is the best alternative to treat candidal infection warranting further experimental preclinical studies.