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Nanotechnology has significant promise in treating microbial diseases by providing precise therapy that targets a broad spectrum of pathogens. Additionally, it plays a pivotal part in the advancement of microbial detection systems, facilitating expedited and precise microbiological diagnoses. The review covers a variety of synthesized nanoparticles (NPs) and different antimicrobial mechanisms that have been explored, with a focus on maintaining scientific rigor in the study. This study also offers significant insights into the synthesis techniques of nanoparticles and the antimicrobial processes investigated, while effectively balancing conciseness and comprehensiveness. Investigated antimicrobial mechanisms include the rupture of bacterial cell membranes, production of reactive oxygen species, and suppression of vital cellular activities. Nanotechnology-produced antimicrobial coatings have shown potential in inhibiting bacterial colonization and decreasing device-associated infections in implanted devices. In addition, nanotechnology-based methods enhance wound healing by enabling the regulated release of medicinal substances and stimulating the regeneration of tissue. This review recognizes the limits and obstacles found in current research while also noting the considerable accomplishments in this subject. These factors include the need for standardized methods of characterizing nanoparticles, enhanced comprehension of nanoparticle toxicity, and comprehensive evaluation of long-term impacts. Examining these constraints enhances the scientific rigor of the analysis.

Recently, the development of skin barrier depend on wound healing, which is one of the most complicated biological processes. As an alternative to conventional antibiotics, nanoparticles (NPs) have become more utilized generally to attack bacteria. Due to their distinct characteristics, potential microbicidal action, and ability to speed up the wound healing process, zinc oxide nanoparticles (ZnO-NPs) have attracted much attention. Biological techniques can solve the restrictions of both physical and chemical approaches for nanoparticles synthesis. Because it does not require expensive chemicals, high temperatures, or a lot of time, biological synthesis is relatively easy, inexpensive, and environmentally benign. The secondary metabolic extract from Escherichia coliwas used in this study to biologically synthesize three distinct quantities of ZnO-NPs, which were then assessed for their effectiveness in wound healing and bacterial infection prevention. The biofabricated ZnO-NPs were fully characterized in terms of particle shape, morphology, and stability against aggregation. Depending on the concentration of the utilized zinc salt, three different samples were fabricated biologically, nominated as ZnO-NPs-1, ZnO-NPs-2, and ZnO-NPs-3. The findings of Uv-vis absorption peaks were obtained at 352 nm, demonstrating the preparation of ZnO-NPs. The results demonstrated the formation of ZnO-NPs with an average particle size of 79.19, 79.83 and 91.57 nm for the three prepared samples (ZnO-NPs-1, ZnO-NPs-2, and ZnO-NPs-3), respectively. Additionally, these samples of ZnO-NPs exhibited zeta potential values around −34.3, −33.7, and −33.4 mV, respectively. Energy dispersive X-ray confirmed the successful formation of ZnO-NPs. It was also observed from the obtained results that, ZnO-NP-3 showed superior antimicrobial potential against selected skin infectious microbes. The effective killing dosage of ZnO-NPs-3 was recorded to be 40 mg/L which can eliminate microbial growth. The dysregulation of skin flora significantly influences the etiology of inflammatory skin disorders.

AbstractAspergillus fumigatusis associated with invasive disease aspergillosis in immunocompromised individuals. The major aim of this study was to investigate the biochemical and immunological responses of male Wistar rats against A. fumigatusexperimentally-induced pulmonary fungal infection. Nostril experimental exposure of male Wistar rats to a high dose of A. fumigatusfreeze-dried preparation for only 24 hr resulted in a significant increase in levels of catalase, nitric oxide and lipid peroxide in lung homogenates, compared to those of the control animals. However, the oxidative status of the lungs of rats challenged with killed fungus did not change significantly, except for the stimulation in the level of lipid peroxide. IgG level was significantly elevated only in rats that received two low doses of fungus, compared to unexposed animals (p< 0.005). Examining the lung of rats exposed to A. fumigatusrevealed no abnormal changes, except for pus in bronchial lumen spaces and per bronchial inflammation. Histologically, large numbers of granuloma cells were evident in the lungs of challenged rats, while no granuloma formation was evident in the lungs of rats exposed to killed fungus.

Beyond energy crises, biodiesel offers renewable and unlimited option to the challenges associated with fossil fuels depletion. Biodiesel could reduce the carbon foot print and gas emissions. Therefore, China has set an audacious goal of carbon neutrality by 2060. In order to reduce the cost of biodiesel production, it is critical to look for alternative feedstocks and unconventional resources. Biodiesel can be produced from renewable and sustainable feedstocks like edible and non-edible oils, insect, municipal sewage sludge, and oleaginous microorganisms. Existing life cycle assessments of yeast-based biodiesel production are required to assess potential environmental impacts and obtain a holistic picture. The circular economy paradigm has recently emerged as a viable alternative to linear, unsustainable production and consumption systems. Given the legislative requirements and the circular economy principle, the use of textile azo dye wastewater is a promising alternative for its management. The annual disposal of 4,500,000 tons of textile dyes is an environmental and socioeconomic concern due to their carcinogenic potential. Azo dyes account for over 70% of global industrial demand. Biological-mediated azo dye degradation is thought to be cost-effective, and environmentally friendly when compared to physical and chemical approaches. To this end, yeasts can play a significant role, owing to their high growth rate, tolerance to extreme conditions, and ability to effectively degrade lignin and aromatic compounds, concurrently representing a highly promising feedstock for biodiesel production. Interestingly, an emphasis has been recently given on novel symbiotic yeasts isolatedfrom termite gutsas promising microbiomes for multiple biotechnological applications. Therefore, this review focuses on recent findings of biodiesel production from azo dye degrading yeasts inhabiting termite guts. While capturing recent research advancements for sustainable biodiesel production, this review emphasizes a novel concept for using azo dyes/aromatic wastes as a feedstock for biodiesel production.

Aspergillus nigerisolated from Allium sativumwas used at large scale fermentation (150 mg flavone/200 mlmedium) to obtain suitable amounts of the products, efficient for identification. Then spectral analysis (UV, IR, 1 H-NMR, 13 C-NMR) and mass spectrometry were performed for the two products, which contributed to the identification process. The metabolite (1) was identified as 2'-hydroxydihydrochalcone, and the metabolite (2) was identified as 2'-hydroxyphenylmethylketone, which were more active than flavone itself. Antioxidant activities of the two isolated metabolites were tested compared with ascorbic acid. Antioxidant activity of metabolite (1) was recorded 64.58% which represented 79% of the antioxidant activity of ascorbic acid, and metabolite (2) was recorded 54.16% (67% of ascorbic acid activity). However, the antioxidant activity of flavone was recorded 37.50% which represented 46% of ascorbic acid activity. The transformed products of flavone have antimicrobial activity against Pseudomonas aeruginosa, Aspergillus flavusand Candida albicans, with MIC was recorded 250 μg/mlfor metabolite (2) against all three organism and 500, 300, and 300 μg/mlfor metabolite (1) against tested microorganisms (P. aeruginosa, Escherichia coli, Bacillus subtilis, and Klebsiella pneumonia, Fusarium moniliforme, A. flavus, Saccharomyces cerviceae, Kluveromyces lactisand C. albicans) at this order.

Ganoderma resinaceumtolerated sodium chloride salt stress within a range of 0 mM till 300 mM. It responded to salt stress with fluctuation in proline formation at different NaCI concentrations. However, the mycelial dry weight, total protein contents and exopolysaceharides did not changed considerably. Increasing sodium chloride concentration led to morphological alteration in fungal mycelia with disappearance of fungal cell wall, plasmolysis, and vacuolation as indicated with electron microscopic examination of the fungal growth.

Toxicity of the fungicide Flutolanil was in vitrotested against 20 isolates of Macrophomina phaseolinaand cotton seedlings of ten commercial cotton cultivars. The isolates were recovered from roots of cotton plants obtained from different cotton-growing areas in Egypt. Most of the tested isolates were sensitive to Flutolanil; however, they varied in sensitivity. Twenty-five percent of the isolates were highly sensitive where IC50ranged from < 1 to 5.1 μg/ml,20% of the isolates were sensitive where IC50ranged from 15 to 30 μg/ml,45% of the isolates were moderately sensitive where 1C50ranged from 46 to 58.5 μg/ml, and 10% of the isolates were not much sensitive (tolerant) where 1C50was > 100 μg/ml.Flutolanil was very safe on both shoots and roots of the tested eultivars (1C50> 100 μg/ml).Treating cotton seeds with Flutolanil resulted in highly significant (P < 0.01) reductions in pathogenicity of 18 isolates and a significant reduction (P < 0.05) in pathogenicity of isolate M29. M1was the only isolate, which was insensitive to the application of Flutolanil. In vivotoxicity to Flutolanil was not correlated with its in vitrotoxicity. However, a highly significant correlation (r = 0.60, P < 0.01) was observed between pathogenicity of isolates and the in vivotoxicity of the fungicide.

AbstractMycobiota including Alternaria alternata, Fusariumverticillioides and Aspergillus pulvérulentswere tested for their ability to uptake radiocobalt (Co-60) and radiocesium (Cs-137) from radionuclide containing medium. A. alternatawas the most efficient fungal species for uptake of radioisotopes, followed by A. pulverulents,whereas F. verticilliodiescame in the last rank. The conditions of radioisotope uptake were optimized such as the form of the fungal organism either spores or mycelium, inoculum age and pH of growing medium. Furthermore the total pigments of the tested fungi were extracted and tested for their ability to bind with radioisotope, where melanin of A. alternataproduced about 60% for radioisotope uptake out of total added radioisotope radioactivity. Moreover, transmission electron microscopic examination of radioisotope exposed spores showed high precipitation of melanin granules in the spore wall and within the cell as comparing to untreated spores.

Bee propolis ethanolic extract with some plant essential oils was investigated for its antidermatophytic properties. The tested plant essential oils included jasmine, clove, lemon, Arabian jasmine, mint, rosa, olive and basil. The antidermatophytic activity has been compared to Naftiflne-HCl and Clotrimazole used for dermatophyte treatment. Experimental model has been tested using sheep hoof plate for the in vitrotests to stimulate human nails. Mint, clove and basil with 4 mg/mlof bee propolis have a comparable efficacy to those of Naftifine-HCl and Clotrimazole. There is a great necessity for new effective low price and safe antidermatophyte agents to avoid recurrent infection. Propolis synergistic could be of great importance with essential oils of plants in dermatophyte therapy.

AbstractAquatic fungi from four brackish water lakes; Edku, Burullus and Manzala lakes which are located at the northern region of Egypt and Qarun lake that located in El-Fayoum city are reported in this manuscript. Twenty-nine fungal species which belong to 19 genera of aquatic fungi were recovered from water samples collected from the studied lakes. The most frequently isolated fungal species were Chytridium conferrop, Allomyces throughoutand Rhizoclosmatium globosum. Thraus- tochytrium amoeboidumand Leptolegniella exoosporushave a moderately occurrence frequency. The maximum fungal count of recovered aquatic fungi was recorded in Burrullus lake followed by EdKu, Manzala and Qarun lakes. This study was extended to test the ability of six selected aquatic fungi (Brevilegniella keratinophila, Blastocladiella cystogena, Chytridium conferrop, Entophlyctis variabilis, Schizochytrium mangroveiand Thraustochytrium rosii),to uptake the radionuclide from their culture medium as a step to biologically treat the waste water or solution with radio-cesium and radio-cobalt. Fifty seven % of Cs-137 and 35% of Co-60 could be removed from liquid waste by the selected aquatic fungi.

Experimental Hypersensitivity Pneumonitis Induced by Fusarium kyushuensein Mice: Koichi Harada, et al. Department of Hygiene, Kumamoto University School of Medicine—Arecently described Fusariumspecies, Fusarium kyushuense, was isolated from dead leaves of egg plant in a greenhouse where a female farmer who developed hypersensitivity pneumonitis (HP) with progressing lung lesions had been working. The freeze dried fungus was exposed to specific pathogen-free, 6-week-old female C57Black/6J mice under light ether anesthesia. Each mouse received 40 µlof the suspended fungal solution by dropping it onto its nostrils in 5 consecutive days a week for 4 wk. The control group received 40 µlof 0.1 M sterilized phosphate buffered saline. The mice were killed on the 4th day after the final exposure. The lung indices increased dose dependently in the fungus exposed mice groups. The specific IgG anti-F.kyushuenselevels in sera of the high dose group were significantly higher than in the control group (P <0.05 by Ryan’s multiple comparison test). Histologically, the lungs of both low and high dose groups showed signs of atelectasis with granulomatous lesions containing multinuclear giant cells and activated macrophages. This is the first report that mice developed HP induced by repeated exposure to freeze dried F. kyushuense.

Experimental Hypersensitivity Pneumonitis Induced by Fusarium kyushuensein Mice: Koichi Harada, et al. Department of Hygiene, Kumamoto University School of Medicine—Arecently described Fusariumspecies, Fusarium kyushuense, was isolated from dead leaves of egg plant in a greenhouse where a female farmer who developed hypersensitivity pneumonitis (HP) with progressing lung lesions had been working. The freeze dried fungus was exposed to specific pathogen‐free, 6‐week‐old female C57Black/6J mice under light ether anesthesia. Each mouse received 40 piof the suspended fungal solution by dropping it onto its nostrils in 5 consecutive days a week for 4 wk. The control group received 40 μlof 0.1 M sterilized phosphate buffered saline. The mice were killed on the 4th day after the final exposure. The lung indices increased dose dependently in the fungus exposed mice groups. The specific IgG anti‐Fkyushuenselevels in sera of the high dose group were significantly higher than in the control group (P <0.05 by Ryan's multiple comparison test). Histologically, the lungs of both low and high dose groups showed signs of atelectasis with granulomatous lesions containing multinuclear giant cells and activated macrophages. This is the first report that mice developed HP induced by repeated exposure to freeze dried F. kyushuense.

Expression of inducible nitric oxide (NO) synthase (iNOS) and related enzymes of arginine metabolism in the mouse lung exposed to filamentous fungus Fusarium kyushuensewas studied by RNA blot, immunoblot, and histological analyses. When mice were exposed intranasally to the fungi only once, no induction of iNOS mRNA was observed. However, when the animals were infected again 6 days after the first exposure, iNOS mRNA was induced, reached a maximum 12–24 h after the exposure, and decreased to an undetectable level at 48 h. mRNAs for cationic amino acid transporter-2 (CAT2) and argininosuccinate synthetase were induced gradually, reached a maximum at 24 h, and decreased at 48 h. Arginase II mRNA increased at 24 h and decreased markedly at 48 h. On the other hand, arginase I mRNA started to increase at 24 h and reached to a much higher level at 48 h. Ornithine decarboxylase and ornithine aminotransferase mRNAs were also induced. Immunoblot analysis showed that iNOS, argininosuccinate synthetase, and arginase I and II proteins were induced with similar kinetics as those of their respective mRNAs. In histological examination, fungal elements were observed in the bronchoalveolar lumen at 3–6 h, decreased at 12 h, and almost disappeared at 48 h. Small granuloma appeared 3 h after the infection and their size increased with time. These results suggest that NO is produced in the mouse lung in response to F. kyushuenseexposure and that the NO production is regulated by CAT2, the citrulline-NO cycle, and arginase isoforms. Enhanced synthesis of polyamines and proline (and thus collagen) is also suggested.

Fatty acid synthetase has been purified from Cryptococcus neoformans 450 fold to a specific activity of 3.6 units per mg protein with an overall yield of 23%. The purified enzyme contained two non-identical subunits, Mr approximately 2.1×105 and 1.8×105. Under optimum conditions, 100 mM KCl and pH 7.5, apparent Km values for the substrates were: Acetyl CoA, 19 µM; Malonyl CoA, 5 µM; and NADPH, 6 µM. Product inhibition patterns were determined to be: CoA, competitive versus acetyl CoA and malonyl CoA, uncompetitive versus NADPH; NADP, competitive versus NADPH, uncompetitive versus acetyl CoA and malonyl CoA; Palmitoyl CoA, competitive versus malonyl CoA, noncompetitive versus acetyl CoA and NADPH; Bicarbonate, uncompetitive versus malonyl CoA. These product inhibition patterns are consistent with the multisite ping-pong mechanism previously proposed for the avian fatty acid synthetase complex. The cryptococcal fatty acid synthetase was inhibited by the polyanionic polymers, heparin and dextran sulfate, an effect never before demonstrated for a fatty acid synthetase. This inhibition exhibited a marked dependence on the length of the polymer chain, with dextran sulfate fractions with Mr of 6×105 and above having Ki values below 100 nanomolar. A model is presented that involves initial binding of the anionic polymer to the enzyme complex at a region of high positive charge density, followed by interaction of the end of the tethered polymer with the catalytic site. This study represents the first purification of fatty acid synthetase from a basidiomycete.

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