Tomato (Lycopersicon esculentum) is one of the widely grown vegetables worldwide. Fusarium oxysporum f. sp. lycopersici (FOL) is the significant contributory pathogen of tomato vascular wilt. The initial symptoms of the disease appear in the lower leaves gradually, trail by wilting of the plants. It has been reported that FOL penetrates the tomato plant, colonizing and leaving the vascular tissue dark brown, and this discoloration extends to the apex, leading to the plants wilting, collapsing and dying. Therefore, it has been widely accepted that wilting caused by this fungus is the result of a combination of various physiological activities, including the accumulation of fungal mycelia in and around xylem, mycotoxin production, inactivation of host defense, and the production of tyloses; however, wilting symptoms are variable. Therefore, the selection of molecular markers may be a more effective means of screening tomato races. Several studies on the detection of FOL have been carried out and have suggested the potency of the technique for diagnosing FOL. This review focuses on biology and variability of FOL, understanding and presenting a holistic picture of the vascular wilt disease of tomato in relation to disease model, biology, virulence. We conclude that genomic and proteomic approachesare greater tools for identification of informative candidates involved in pathogenicity, which can be considered as one of the approaches in managing the disease.

Cinnamomum verum plant extract mediated propellant chemistry route was used for the green synthesis of zinc oxide nanoparticles. Prepared samples were confirmed for their nano regime using advanced characterization techniques such as powder X-ray diffraction and microscopic techniques such as scanning electron microscopy and transmission electron microscopy. The energy band gap of the green synthesized zinc oxide (ZnO)-nanoparticles (NPs) were found between 3.25–3.28 eV. Fourier transmission infrared spectroscopy shows the presence of Zn-O bond within the wave number of 500 cm−1. SEM images show the specific agglomeration of particles which was also confirmed by TEM studies. The green synthesized ZnO-NPs inhibited the growth of Escherichia coli and Staphylococcus aureus with a minimum inhibitory concentration (MIC) of 125 µg mL−1 and 62.5 µg mL−1, respectively. The results indicate the prepared ZnO-NPs can be used as a potential antimicrobial agent against harmful pathogens.

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Purpose The study aimed to find an effective method for fungal-mediated synthesis of zinc oxide nanoparticles using endophytic fungal extracts and to evaluate the efficiency of synthesized ZnO NPs as antimicrobial and anticancerous agents. Methods Zinc oxide nanoparticles (ZnO NPs) were produced from zinc nitrate hexahydrate with fungal filtrate by the combustion method. The spectroscopy and microscopy techniques, such as ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX), dynamic light scattering (DLS), and transmission electron microscopy (TEM) with selected area electron diffraction (SAED), were used to characterize the obtained product. Antibacterial activity on Gram-positive ( Staphylococcus aureus and Bacillus cereus ) and Gram-negative ( Pseudomonas aeruginosa and Escherichia coli ) samples was tested by broth microplate dilution technique. ZnO NPs antifungal activity was determined against plant pathogenic and regular contaminating fungi using the food-poison method. The anticancerous assay of the synthesized ZnO NPs was also investigated by cell uptake, MTT assay, and apoptosis assay. Results The fungal synthesized ZnO NPs were pure, mainly hexagonal in shape and size range of 34–55 nm. The biosynthesized ZnO NPs could proficiently inhibit both Gram-positive and Gram-negative bacteria. ZnO NPs synthesized from fungal extract exhibited antifungal activity in a dose-dependent manner with a high percentage of mycelial inhibition. The cell uptake analysis of ZnO NPs suggests that a significant amount of ZnO NPs (1 μg/mL) was internalized without disturbing cancer cells’ morphology. As a result, the synthesized ZnO NPs showed significant anticancer activity against cancer cells at 1 μg/mL concentration. Conclusion This fungus-mediated synthesis of ZnO NPs is a simple, eco-friendly, and non-toxic method. Our results show that the synthesized ZnO NPs are an excellent novel antimicrobial and anticancer agent. Further studies are required to understand the mechanism of the antimicrobial, anticancerous action of ZnO NPs and their possible genotoxicity.

For the first time, different morphologies of zinc oxide (ZnO) superstructures are synthesized by a simple and environmental friendly route using Nerium oleander leaf extract as fuel. Powder X-ray diffraction, scanning electron microscopy, UV−visible spectroscopy, and photoluminescence studies are performed to ascertain the formation and characterization of ZnO. X-ray diffraction confirmed the crystalline nature of the compound with hexagonal Wurtzite structure. When the concentration of the leaf extract is varied, different morphologies are formed. ZnO are tested for antifungal using soybean seed-borne fungi by food-poison method and antibacterial activity against bacterial human pathogens by a broth microplate dilution method using 96-well plates. Among the screened soybean seed-borne fungi, Fusarium equisiti was found to be more susceptible, which was followed by Macrophomina phaseolina for ZnO nanoparticles (NPs) prepared using 0.2188 mol/dm 3 N. oleander leaf extract. It was observed that NPs exhibited pronounced antifungal activity in a dose-dependent manner with a relatively high percentage of mycelial inhibition. ZnO obtained with the concentration of 0.2188 mol/dm 3 leaf extract showed both minimum inhibitory concentration and minimum bactericidal concentration effectiveness compared to other synthesized compounds. It is observed that the samples with small crystallite size show greater antibacterial activity than those of larger crystallite size. Further, we found that crystallite size and morphology significantly affects the antibacterial activity of ZnO. Prepared compounds showed significant inhibition against Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Pseudomonas aeurginosa. Among the tested bacteria, P. aeurginosa is more susceptible and E. coli is the least effective against bacterial pathogens. The antibacterial activities of the as-formed ZnO are preliminarily studied against Gram-positive (B. subtilis and S. aureus) and Gram-negative (E. coli and P. aeruginosa) bacteria and are found to be dependent on the shape of the nanostructures.

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Dillenia indica L. is a traditional medicinal plant well known for its ability to cure various human diseases. In the current study, silver nanoparticles have been synthesized by simple and eco‐friendly method using Dillenia indica extract. The green synthesized nanoparticles were characterized by Fourier transform infrared (FTIR), UV–visible spectroscopy, Atomic force microscopy (AFM), High‐resolution transmission electron microscopy (HR‐TEM), Zeta Potential and Size Distribution. UV–visible and FTIR spectra, AFM, HR‐TEM and Zeta Potential readings and size distribution conformed that the synthesized silver particles were in the size of nano. The green synthesized silver nanoparticles were subjected for antibacterial activity against Gram‐positive bacteria Enterococcus faecalis and Gram‐negative bacteria Escherichia coli by agar well diffusion method. The synthesized AgNPs exhibited significant inhibition of 27 and 16 mm against the test bacteria at 0.25 mg/ml. Further the antibacterial activity was confirmed by live and dead cell assay by fluorescence microscopy and morphological changes of bacteria were studied by Scanning electron microscope (SEM). The study recommends that the synthesized silver nanoparticles using Dillenia indica extract have potential application in inhibition of bacteria owing to their potent antibacterial activity.

Fusarium graminearum is a leading plant pathogen that causes Fusarium head blight, stalk rot, and Gibberella ear rot diseases in cereals and posing the immense threat to the microbiological safety of the food. Herein, we report the green synthesis of zinc oxide nanoparticles from Syzygium aromaticum (SaZnO NPs) flower bud extract by combustion method and investigated their application for controlling of growth and mycotoxins of F. graminearum . Formation of SaZnO NPs was confirmed by spectroscopic methods. The electron microscopic (SEM and TEM) analysis revealed the formation of triangular and hexagonal shaped SaZnO NPs with size range 30–40 nm. The synthesized SaZnO NPs reduced the growth and production of deoxynivalenol and zearalenone of F. graminearum in broth culture. Further analysis revealed that treatment of mycelia with SaZnO NPs resulted in the accumulation of ROS in the dose-dependent manner. Also, SaZnO NPs treatment enhanced lipid peroxidation, depleted ergosterol content, and caused detrimental damage to the membrane integrity of fungi. Moreover, SEM observations revealed that the presence of diverged micro-morphology (wrinkled, rough and shrank surface) in the macroconidia treated with SaZnO NPs. Taken together, SaZnO NPs may find a potential application in agriculture and food industries due to their potent antifungal activity.