Tetraconazole, a chiral triazole fungicide, is widely used for the prevention of plant disease in wheat fields. However, the chirality of pesticides like tetraconazole can cause diverse biological responses. Therefore, it is important that research is conducted to investigate the enantioselective effects of chiral enantiomers in this regard. The absolute configurations of two tetraconazole enantiomers were initially confirmed by ECD (Electrostatic circular dichroism). The bioassay test showed that the fungicidal activity of (R)-(+)-tetraconazole against two pathogens (R. cerealis and F. graminearum) was approximately 1.49–1.98 times greater than that for (S)-(−)- tetraconazole. Following recovery experiments, a modified QuEchERS (Quick, easy, cheap, effective, rugged, safe) method was established using UPLC-MS/MS (ultra-performance liquid chromatography tandem mass spectrometry). The mean recoveries from plant and soil sample ranged from 78.9% to 100.5% with intraday relative standard (RSDᵣ) values of 0.8%–6.9% and interday relative standard (RSDR) values of 3.0%–5.2% respectively. The stereoselective degradation of tetraconazole in wheat meant that (S)-(−)-tetraconazole was more rapidly degraded than (R)-(+)-tetraconazole. Conversely, (R)-(+)-tetraconazole was preferentially degraded in wheat soil. These results will provide us with a greater understanding when assessing future environmental risk assessments and strategies that invoke pesticide reduction.

Azoles are effective antifungal agents used in both medicine and agriculture. They typically work by inhibiting cytochrome P450 enzymes, primarily CYP51 of the ergosterol biosynthesis pathway, thus damaging the fungal cell membrane. However, apart from their desired antifungal properties, several azoles also exhibit endocrine disrupting properties in mammals, both in vitro and in vivo. Here, we have tested two currently used agricultural azole fungicides, triticonazole and flusilazole, for their in vitro anti-androgenic activity and potential effects on reproductive parameters. Both fungicides showed strong androgen receptor (AR) antagonism and disruption of steroid biosynthesis in vitro. Following gestational exposure to flusilazole (15 or 45 mg/kg bw/day) or triticonazole (150 or 450 mg/kg bw/day) in time-mated Sprague Dawley rats, triticonazole induced shorter male anogenital distance (AGD). Flusilazole exposure did not affect the AGD, but altered fetal male blood hormone profile, with increased androstenedione and decreased estrone levels. Flusilazole and triticonazole have dissimilar effects on reproductive parameters in vivo, but both show endocrine disrupting activities.

Following the recent progress in magnetic nanotechnology, concern over the optimal benefits and potential risks of iron oxide nanoparticles (Fe NPs), has increased. Hence, to minimize the negative impacts of inorganic Fe NPs, we report the phyco-synthesis and characterization of superparamagnetic Fe3O4 NPs via reduction of ferric/ferrous chloride solution (2:1 M ratio; 88 °C) with green macroalga, Ulva flexuosa (wulfen) J.Agardh aqueous extract. The biogenic process is clean, eco-friendly, rapid, and facile to handle. These green fabricated magnetite NPs are characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), particle size analysers (PSA), zeta potential (ZP) measurement, and vibrating sample magnetometry (VSM) techniques. The results confirmed that the cubo-spherical, polydisperse of biosynthesized Fe3O4 NPs with an average diameter of 12.3 nm was formed. The antagonistic effects of algal extract, chemo-route and U. flexuosa-derived Fe3O4 MgNPs on selective human pathogenic microbes (i.e. n = 11) resulted in strong antibacterial and moderate antifungal activity. The comparative toxic and reproductive effects of the chemo- and bio-routes of Fe3O4-MgNPs against rotifer B. rotundiformis exhibited low acute toxicity with a lower inducing effect of biogenic nano-magnetite on reduction rotifer reproductive rate than its chemogenic counterpart. In view of the nanoecotoxicity, though the current study covered a wide range of exposure concentrations (10-500 mg/L) of organic and inorganic nano sizes of Fe3O4 in brackish water rotifer, a biotoxicity assay at higher dosage or a comprehensive risk assessment in different aqua-organisms is recommended.

In this study, Curcubita maxima leaves are used as a novel source for green synthesis of reduced graphene oxide — silver nanoparticle composite in a single pot. Characterization of the novel phyto source–driven composite was performed by UV–visible spectroscopy, Fourier transform infrared analysis, X-ray diffraction analysis, and field emission scanning electron microscopic methods. The assessment of degradation effect of chlorpyrifos by the synthesized nanocomposite was performed. The photocatalytic activity of the composite was demonstrated through two different processes as adsorption under room temperature and photocatalysis in the presence of sunlight. Different parameters such as pH, time, photocatalyst dose and pesticide concentration were optimized. The adsorption isotherms governing the photocatalytic adsorption process were investigated to predict the adsorption capacity of the synthesized nanocomposite. In addition, the results of antimicrobial activity of the nanocomposite against gram-positive, gram-negative bacteria and antifungal activity were also been found to be highly promising to utilize this composite for the removal of microbial contaminations in wastewater treatment.

Biodegradable polymer poly(3-hydroxybutyrate) (P3HB) has been used as a matrix to construct slow-release formulations of the fungicide tebuconazole (TEB). P3HB/TEB systems constructed as films and pellets have been studied using differential scanning calorimetry, X-ray structure analysis, and Fourier transform infrared spectroscopy. TEB release from the experimental formulations has been studied in aqueous and soil laboratory systems. In the soil with known composition of microbial community, polymer was degraded, and TEB release after 35 days reached 60 and 36 % from films and pellets, respectively. That was 1.23 and 1.8 times more than the amount released to the water after 60 days in a sterile aqueous system. Incubation of P3HB/TEB films and pellets in the soil stimulated development of P3HB-degrading microorganisms of the genera Pseudomonas, Stenotrophomonas, Variovorax, and Streptomyces. Experiments with phytopathogenic fungi F. moniliforme and F. solani showed that the experimental P3HB/TEB formulations had antifungal activity comparable with that of free TEB.

Pure NiO and NiO thin films doped with 0.1 to 25% Cu were grown on pre-heated soda-lime glass substrates via spray pyrolysis technique. The surface roughness of the NiO:Cu thin films decreased as Cu/Ni ratio was increased. Antifungal activity of these thin films against Aspergillus niger (A. niger) which affects some of the fruits, and Macrophomina phaseolina (M. phaseolina) which is a soil borne fungus responsible for the infection of root and lower stem of several plants, was then investigated by bioassay and broth dilution methods. The antifungal response of pure NiO thin film was weak but it improved considerably on doping with copper. The higher the copper content in NiO:Cu thin film, the better was its antifungal response. Moreover, for the given Cu/Ni ratio range of 0–25%, the optical density (OD) of Potato Dextrose (PD) broth inoculated with A. niger and containing NiO:Cu material was reduced or antifungal ability was enhanced by 8.3, 9.9, 11.7, and 13.4 times for the exposure time of 6, 8, 10, and 12 days, respectively. Similarly, the OD of PD broth inoculated with M. phaseolina and containing NiO:Cu material was reduced or antifungal ability was enhanced by 16–37 times in the exposure temperature range of 20–40 °C. A linear relationship of OD with crystallite size and lattice strain of the thin films showed that NiO:Cu material possessed memory of the structural modifications induced by the dopant atoms though its phase changed from crystalline to non-crystalline state. These results can be utilized in agricultural sector. Graphical abstract

This study is focused on the analysis of regional variation of the chemical compositions of three Clinopodium menthifolium subsp. ascendens (Jord.) Govaerts Tunisian accession, as well as their inhibition toward fungi and insect pests. The diversity of the chemical constituents and biological activities in front of the aforementioned variations was found to be remarkable. Essential oils were obtained by hydrodistillation of the aerial parts and analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 41, 42, and 30 compounds were identified respectively from Clinopodium menthifolium essential oils harvested from three Tunisian regions, namely Ain-Draham (ADEO), Babouch (BEO), and Tabarka (TEO). All analyzed oils were rich in oxygenated monoterpenes with different major constituents. Piperitenone (34.5%), cis-piperitone oxide (26.1%), and pulegone (47.9%) were the dominant compounds in the three volatile oils, respectively. The antifungal activity was investigated in vitro using six targeted fungal strains (Aspergillus flavus, Aspergillus terreus, Candida albicans, Microsporum canis, Microsporum gypseum, and Trichophyton mentagrophytes). The toxicity and repellency of essential oils were evaluated against the stored product pest Tribolium confusum. The tested samples were differently effective toward the target fungi and the pest depending on the variability of their chemical compositions. BEO exhibited the highest fungitoxic properties toward A. terreus mold, M. canis dermatophyte, and C. albicans yeast (the MIC values ranged from 40 to 400 μg mL⁻¹). In addition, the data showed that TEO repelled T. confusum moderately (PR = 42.5% at 2 h after exposure). Concerning the contact treatment, both ADEO and BEO were proved to possess slightly toxic effects toward T. confusum pest (% of mortality 27.5–32.5% at 5% concentration). The results showed that the geographic origin greatly influenced the chemical composition and the associated bioactivities of Clinopodium menthifolium subsp. ascendens.

The novelty of the present research is conducting a new method in the systemic resistance of plant diseases by using distinct marine extracts. The ability of two octopus extracts to reduce the wilt disease caused by Fusarium oxysporum was observed. The applied methods are soaked roots (SR) and foliar shoots (FS). The antioxidant enzyme activities, percent disease index (PDI), and growth parameters were measured. In vitro antifungal potential of the octopus extracts against F. oxysporum was examined. The obtained result shows that SR extracts reduced PDI. Additionally, all the tested treatments promoted the growth and photosynthetic pigments of the infected plants. SR (in ethanolic extracts) was the most prominent inducer which offered a high advancement in the total soluble protein contents. Also, SR (in methanolic extracts) was the most suitable inducer which provided a very necessary development not only in the total phenol but also in the peroxidase (POD) and polyphenol oxidase (PPO) activities. GC-MS investigation of the octopus extracts exhibited that the compounds which possess antifungal activity were furoscrobiculin B and/or eugenol. They demonstrated a notable antifungal potential against F. oxysporum with a maximum activity of 38.5 and 12.7 mm ZOI after the treatment with the ethanolic and methanolic extract, respectively. FTIR results illustrated the functional group of the compound responsible for the antifungal activity. Additionally, an atomic absorption result reveals that there are traces of metals detected such as Pb, Ag, Cu, Zn, and Mg. The antifungal activity was decreased as the concentrations were reduced. Accordingly, the present extracts may be used as the vital agents in the agricultural field to restrain the plant pathogenic fungi, especially F. oxysporum from a proliferation.

Biological methods offer eco-friendly and cost-effective alternatives for the synthesis of silver nanoparticles (AgNPs). The present study highlights a green process where AgNPs were synthesized and optimized by using silver nitrate (AgNO₃) and the aqueous extract of Piper betle (Pbet) leaf as the reducing and capping agent. The stable and optimized process for the synthesis of Pbet-AgNPs was exposure of reaction mixture into the sunlight for 40 min, pH 9.0, and 2 mM AgNO₃ using 1:4 diluted Pbet leaf aqueous extract. The optimized Pbet-AgNPs were characterized by UV–visible spectroscopy, high-resolution field emission scanning electron microscopy (FE-SEM), X-ray diffractometry (XRD), and Fourier-transform infrared spectroscopy (FTIR). The prepared Pbet-AgNPs were spherical in shape with size in the range of 6–14 nm. These nanoparticles were stable for 6 months in aqueous solution at room temperature under dark conditions. The biogenic synthesized Pbet-AgNPs are found to have significant antifungal activity against plant pathogenic fungi, Alternaria brassicae and Fusarium solani. Synthesized Pbet-AgNPs potentially reduced the fungal growth in a dose-dependent manner. Microscopic observation of treated mycelium showed that Pbet-AgNPs could disrupt the mycelium cell wall and induce cellular permeability. Protein leakage assay supports these findings. Overall, this study revealed the efficacy of green synthesized AgNPs to control the plant fungal pathogens. Pbet leaves are a rich source of phenolic biomolecule(s). It was hypothesized that these biomolecule(s) mediated metal reduction reactions. In this context, the present work investigates the phytobiomolecule(s) of the aqueous extract of Pbet leaves using high-resolution liquid chromatography–mass spectroscopy (HR-LCMS) method. The analysis revealed that eugenol, chavicol, and hydroxychavicol were present in the Pbet aqueous extract.

Ester-functionalized pyridinium ionic liquids (ILs), 1-decyloxycarbonylmethylpyridinium chloride (PyrСOOC₁₀-Cl), and 1-dodecyloxycarbonylmethylpyridinium chloride (PyrСOOC₁₂-Cl) have been synthesized and studied for their environmental toxicity. Simple long-chain pyridinium ILs, 1-dodecylpyridinium chloride (PyrC₁₂-Cl), and commercial disinfectant cetylpyridinium chloride (CPC) were used as reference compounds. Both ester-functionalized ILs and CPC showed significantly reduced antibacterial activity compared to PyrC₁₂-Cl. However, ester-functionalized ILs were found to have excellent antifungal activity towards Candida albicans fungus strains, similar to PyrC₁₂-Cl and much higher than for CPC. The molecular docking of ILs in the active site of the known antifungal target N-myristoyltransferase (Nmt) C. albicans has been conducted. The obtained results indicate the possibility of ILs binding into the Nmt pocket. The high stability of the complexes, especially for PyrCOOC₁₀-Cl, is ensured by hydrogen bonding, electrostatic anion-pi interactions, as well as hydrophobic pi-alkyl and alkyl interactions that was confirmed by calculated binding energy values. The acute toxicity studies of ester-functionalized ILs on D. rerio (zebrafish) hydrobiont have shown their dramatically reduced ecotoxicity compared to PyrC₁₂-Cl and CPC. Thus, LD₅₀ values of 15.2 mg/L and 16.8 mg/L were obtained for PyrCOOC₁₀-Cl and PyrCOOC₁₂-Cl, respectively, whereas CPC had LD₅₀ value of 0.018 mg/L. The primary biodegradation test CEC L-33-A93 of ILs indicated an improved biodegradability of ester-functionalized compounds compared to simple long-chain ILs. Based on the obtained results, PyrCOOC₁₀-Cl may be considered as very promising cationic biocide due to the combination of soft antimicrobial activity and reduced ecotoxicity, as well as improved biodegradability.