Mycosynthesis of bimetallic zinc oxide and titanium dioxide nanoparticles for control of Spodoptera frugiperda

Aspergillus fumigatus-induced biogenic silver nanoparticles' efficacy as antimicrobial and antibiofilm agents with potential anticancer activity: an in vitro investigation

A worldwide hazard to human health is posed by the growth of toxic bacteria that have contaminated fresh, processed, cereal, and seed products in storage facilities. As the number of multidrug-resistant pathogenic microorganisms rises, we must find safe, and effective antimicrobials. The use of green synthesis nanoparticles to combat microbial pathogens has gained a rising interest. The current study showed Aspergillus fumigatus was applied as a promising biomass for the green synthesis of biogenic silver nanoparticles (Ag NPs). The UV-visible spectra of biosynthesized Ag NPs appeared characteristic surface plasmon absorption at 475 nm, round-shaped with sizes ranging from 17.11 to 75.54 nm and an average size of 50.37 ± 2.3 nm. In vitro tests were conducted to evaluate the antibacterial, antioxidant, and anticancer effects of various treatment procedures for Ag NP applications. The synthesized Ag NPs was revealed biological activity against Aspergillus flauvas, A. niger, Bacillus cereus, Candida albicans, Esherichia coli, Pseudomonas aerugonosa, and Staphylococcus aureus under optimum conditions. The test bacteria were sensitive to low Ag NPs concentrations. (5, 10, 11, 8, 7, 10, and 7 mg/mL) was observed for the mentioned-before tested microorganisms, respectively. The bacterial pathogens described above experienced their biofilm formation effectively suppressed by Ag NPs at sub-inhibitory doses. Ag NPs were tested using scanning electron microscopy (SEM) to verify their antibacterial efficacy towards S. aureus and P. aeruginosa. These findings clearly show how harmful Ag NPs are to pathogenic bacteria. The Ag NPs showed antitumor activity with IC50 at 5 μg/mL against human HepG-2 and MCF-7 cellular carcinoma cells, while 50 mg/mL was required to induce 70% of normal Vero cell mortality. These findings imply that green synthetic Ag NPs can be used on cancer cell lines in vitro for anticancer effect beside their potential as a lethal factor against some pathogenic microbes.

Emerging trends to replace pesticides with nanomaterials: Recent experiences and future perspectives for ecofriendly environment

Despite the widespread usage to safeguard crops and manage pests, pesticides have detrimental effects on the environment and human health. The necessity to find sustainable agricultural techniques and meet the growing demand for food production has spurred the quest for pesticide substitutes other than traditional ones. The unique qualities of nanotechnology, including its high surface area-to-volume ratio, controlled release, and better stability, have made it a promising choice for pest management. Over the past ten years, there has been a noticeable growth in the usage of nanomaterials for pest management; however, concerns about their possible effects on the environment and human health have also surfaced. The purpose of this review paper is to give a broad overview of the worldwide trends and environmental effects of using nanomaterials in place of pesticides. The various types of nanomaterials, their characteristics, and their possible application in crop protection are covered. The limits of the current regulatory frameworks for nanomaterials in agriculture are further highlighted in this review. Additionally, it describes how standard testing procedures must be followed to assess the effects of nanomaterials on the environment and human health before their commercialization. In order to establish sustainable and secure nanotechnology-based pest control techniques, the review concludes by highlighting the significance of taking into account the possible hazards and benefits of nanomaterials for pest management and the necessity of an integrated approach. It also emphasizes the importance of more investigation into the behavior and environmental fate of nanomaterials to guarantee their safe and efficient application in agriculture.

Preparation and activity of sodium carboxymethyl cellulose (CMC-Na) and Metarhizium rileyi ZHKUMR1 composite membrane

Improving the adhesion capability of Metarhizium rileyi ZHKUMR1 on leaves enabled by the combination with Carboxymethyl Cellulose (CMCNa) materials is feasible to improve the utilization rate of Metarhizium rileyi. Herein, the CMC-Na-ZHKUMR1 membrane was prepared by simply mixing Carboxymethyl Cellulose (CMCNa) with Metarhizium rileyi. Through compatibility test, it was found that the inhibition rates of spore germination and mycelial growth of ZHKUMR1 were only 1.51 % and 3.13 % when the concentration of Carboxymethyl Cellulose (CMCNa) was 0.5 %. By adding 2 % of Carboxymethyl Cellulose (CMCNa) under UV irradiation for 30 min, the protective rate of spore germination of ZHKUMR1 was up to ~12.44 %, where the wettability on corn leaves was achieved and the retention of ZHKUMR1 spores on corn leaves was increased. After indoor activity determination, it was found that after 3 min of simulated rain washing, the lethal rate of corn leaves pretreated with CMC-Na-ZHKUMR1 on the 2nd instar larvae of Spodoptera frugiperda was 46.67 %, which was much higher than that of ZHKUMR1 spore suspension alone. This work clearly showed that Carboxymethyl Cellulose (CMCNa) effectively improved the field application effect of Metarhizium rileyi ZHKUMR1, and this strategy provided guidance for improving the field efficacy of Metarhizium rileyi ZHKUMR1.

A review of physical, chemical and biological synthesis methods of bimetallic nanoparticles and applications in sensing, water treatment, biomedicine, catalysis and hydrogen storage

This article provides an in-depth analysis of various fabrication methods of bimetallic nanoparticles (BNP), including chemical, biological, and physical techniques. The review explores BNP's diverse uses, from well-known applications such as sensing water treatment and biomedical uses to less-studied areas like breath sensing for diabetes monitoring and hydrogen storage. It cites results from over 1000 researchers worldwide and >300 peer-reviewed articles. Additionally, the article discusses current trends, actionable recommendations, and the importance of synthetic analysis for industry players looking to optimize manufacturing techniques for specific applications. The article also evaluates the pros and cons of various fabrication methods, highlighting the potential of plant extract synthesis for mass production of capped BNPs. However, it warns that this method may not be suitable for certain applications requiring ligand-free surfaces. In contrast, physical methods like laser ablation offer better control and reactivity, especially for applications where ligand-free surfaces are critical. The report underscores the environmental benefits of plant extract synthesis compared to chemical methods that use hazardous chemicals and pose risks to extraction, production, and disposal. The article emphasizes the need for life cycle assessment (LCA) articles in the literature, given the growing volume of research on nanotechnology materials. This article caters to researchers at all stages and applies to various fields applying nanomaterials.

Biosynthesized metal oxide nanoparticles for sustainable agriculture: next-generation nanotechnology for crop production, protection and management

The current agricultural sector is not only in its most vulnerable state but is also becoming a threat to our environment due to expanding population and growing food demands along with worsening climatic conditions. In addition, numerous agrochemicals presently being used as fertilizers and pesticides have low efficiency and high toxicity. However, the rapid growth of nanotechnology has shown great promise to tackle these issues replacing conventional agriculture industries. Since the last decade, nanomaterials especially metal oxide nanoparticles (MONPs) have been attractive for improving agricultural outcomes due to their large surface area, higher chemical/thermal stability and tunable unique physicochemical characteristics. Further, to achieve sustainability, researchers have been extensively working on ecological and cost-effective biological approaches to synthesize MONPs. Hereby, we have elaborated on recent successful biosynthesis methods using various plants/microbes. Furthermore, we have elucidated different mechanisms for the interaction of MONPs with plants, including their uptake/translocation/internalization, photosynthesis, antioxidant activity, and gene alteration, which could revolutionize crop productivity/yield through increased nutrient amount, photosynthesis rate, antioxidative enzyme level, and gene upregulations. Besides, we have briefly discussed about functionalization of MONPs and their application in agricultural-waste-management. We have further illuminated recent developments of various MONPs (Fe₂O₃/ZnO/CuO/Al₂O₃/TiO₂/MnO₂) as nanofertilizers, nanopesticides and antimicrobial agents and their implications for enhanced plant growth and pest/disease management. Moreover, the potential use of MONPs as nanobiosensors for detecting nutrients/pathogens/toxins and safeguarding plant/soil health is also illuminated. Overall, this review attempts to provide a clear insight into the latest advances in biosynthesized MONPs for sustainable crop production, protection and management and their scope in the upcoming future of eco-friendly agricultural nanotechnology.

Biosynthesis and characterization of silver nanoparticles from symbiotic bacteria Xenorhabdus nematophila and testing its insecticidal efficacy on Spodoptera litura larvae

Spodoptera litura, one of the polyphagous pests, causes huge economical lose and use of chemical pesticide causes impact to the environmental. The present study deals with the use of cell- free supernatant of bacteria Xenorhabdus nematophila NP-1 strain for synthesizing silver nanoparticles and analyzing its larvicidal ability against Spodoptera litura. Color change from yellow to dark brown specifies the synthesis of AgNPs. UV-Vis spec indicates the presences of AgNPs at 440 nm λ_max and functional groups; alcohols, carboxylic acids, aromatics, alkylhalides, ethers and phenols were confirmed by FTIR. SEM revealed the synthesized AgNPs is in spherical shape, EDaX confirms the elemental composition and the crystalline nature were observed using XRD. GC-MS analysis showed presence of Benzencepropanoic acid, 1, 3, 5 Trichloropent-2-ene, 1,1-Dichloro-2,3- dicmethycycloprone and 1,2-benzenedicarboxylic acid bioactive compounds some of which may be responsible for insecticidal and antibacterial activity. The antibacterial activity against S. aureus, B. subtilis and K. pneumoniae showed maximum zone of inhibition at 100 µL/mL. Larvicidal activity of S. litura shows highest mortality at 48 h. In potted plant experiment, AgNPs treated plants showed less damage, with less leaf consumption by S. litura larvae. Further, the synthesis of AgNPs were targeted to zebrafish embryos (non- target organism) and it didn't exhibit any toxic effect even at higher concentration. Our experiment concludes that, AgNPs synthesized using NP-1 strain has highest antimicrobial and insecticidal activity, which can be used in biomedical and biopesticides.

Dissolution kinetics and solubility of copper oxide nanoparticles as affected by soil properties and aging time

Nano copper oxide (CuO NP) was added to eight soils to study the effect of aging time of copper on the concentration of diethylenetriaminepentaacetic acid (DTPA)-extracted copper (DTPA-Cu), with bulk copper oxide (CuO BP) and copper nitrate [Cu(NO₃)₂] used for comparison. Moreover, the effect of soil properties on the dissolution of CuO NP was studied. A dissolution model was used to quantitatively describe the dissolution kinetics of CuO NPs in different soils. The results showed that the concentration of DTPA-Cu decreased with increasing aging time in soils spiked with Cu(NO₃)₂, while the concentration increased to varying degrees in soils spiked with CuO NPs or CuO BPs. In acidic soils, the equilibrium concentrations of DTPA-Cu were 93.3-98.7 mg·kg^-1 for CuO NP treatments, 65.5-94.3 mg·kg^-1 for CuO BP treatments, and 81.4-90.0 mg·kg^-1 for Cu(NO₃)₂ treatments, which were greater than those in alkaline soils (43.4-56.9 mg·kg^-1, 6.26-8.61 mg·kg^-1, and 73.9-80.0 mg·kg^-1, respectively). In acidic soils, DTPA-Cu equilibrium concentration ranked the different forms of copper treatments as CuO NPs > Cu(NO₃)₂ > CuO BPs, while in alkaline soils, the order was Cu(NO₃)₂ > CuO NPs > CuO BPs. The dissolution rate constants and solubility of CuO NPs were 0.33-6.42 and 37.1-100.1 mg·kg^-1, respectively. Pearson correlation analysis indicated that the dissolution parameters of CuO NPs were negatively correlated with soil pH and positively correlated with the contents of organic matter, clay, iron oxides, and aluminum oxides. Further, the dissolution rate constant and solubility of CuO NPs could be well predicted by soil pH and the content of free or amorphous aluminum. Our study identified the main factors controlling the dissolution of CuO NPs in farmland soils and highlighted the higher availability of CuO NPs in acidic soils.