Effect of formaldehyde exposure on phytochemical content and functional activity of Agaricus bisporus (Lge.) Sing.

In this study, the effect of formaldehyde on phytochemical content and antioxidant activity of Agaricus bisporus was investigated. Synthetic compost based on wheat straw was prepared by fermentation and disinfection. After steam pasteurization, 5 g of A. bisporus mycelia were inoculated into 1 kg of compost. To determine the effects of formaldehyde, 2, 4, and 6% concentrations were added to the composts, while compost without formaldehyde was used for the control group. The harvesting period was set at 10 weeks. Total phenolic and flavonoid content, macro- and microelement profile, and phenolic content were analyzed in the harvested A. bisporus samples. Macro- and microelement content was determined by ICP-OES, and phenolic compound profile was determined by LC-MS/MS analysis. Formaldehyde levels in A. bisporus samples were determined by the acetylacetone spectrophotometry method. The antioxidant capacity of A. bisporus samples was determined by DPPH scavenging activity; antimutagenic effects of samples were determined by Allium test. Application of 2, 4, and 6% formaldehyde resulted in a 1.12-, 1.19-, and 2.07-fold reduction in total phenolic content, respectively. The total phenolic content was reduced between 34.4% and 71.8%. These changes were confirmed by LC-MS/MS analysis. Compounds such as protocatechuic acid, salicylic acid, ferulic acid, and 4-OH benzoic acid, which were detected in the control group, could not be detected in the samples treated with 6% formaldehyde, and it was found that the application of formaldehyde reduced the phenolic content. Similar changes were also observed in macro- and microelements, and significant changes in elemental contents were observed after formaldehyde application. While the presence of formaldehyde at a low level, which may be due to natural production, was detected in the control group, a residue of 11.41 ± 0.93 mg/kg was determined in the 6% FMD applied group. All these changes resulted in a decrease in the antioxidant activity of A. bisporus. The DPPH scavenging activity, which was determined in the range of 21.6-73.3% in the control samples, decreased to 12.3-56.7% in the samples treated with formaldehyde. These results indicate that the application of formaldehyde at different stages of A. bisporus cultivation leads to significant changes in the nutritional value and biological activity of A. bisporus.

Direct and indirect toxicity mechanisms of the natural insecticide azadirachtin based on in-silico interactions with tubulin, topoisomerase and DNA.

Natural pesticides, which attract attention with safe properties, pose a threat to many non-target organisms, so their toxic effects should be studied extensively. In this study, the toxic effects of Azadirachtin, a natural insecticide derived from Azadirachta indica, were investigated by in-vivo and in-silico methods. In-vivo toxic effects were determined using the Allium test and bulbs were treated with 5 mg/L (0.5x EC50), 10 mg/L (EC50), and 20 mg/L (2xEC50) Azadirachtin. In the groups treated with Azadirachtin, there was a decline in germination-related parameters and accordingly growth was delayed. This regression may be related to oxidative stress in the plant, and the increase in malondialdehyde and proline levels in Azadirachtin-applied groups confirms oxidative stress. Azadirachtin toxicity increased dose-dependently and the most significant toxic effect was observed in the group administered 20 mg/L Azadirachtin. In this group, the mitotic index decreased by 43.4% and sticky chromosomes, vagrant chromosomes and fragments were detected at rates of 83.1 ± 4.01, 72.7 ± 3.46 and 65.1 ± 3.51, respectively. By comet analysis, it was determined that Azadirachtin caused DNA fragmentation, and tail DNA, which was 0.10 ± 0.32% in the control group, increased to 34.5 ± 1.35% in the Azadirachtin -treated groups. These cytotoxic and genotoxic effects of Azadirachtin may be due to direct interaction with macromolecules as well as induced oxidative stress. Azadirachtin has been found to interact in-silico with alpha-tubulin, beta-tubulin, topoisomerase I and II, and various DNA sequences. Possible deteriorations in macromolecular structure and functions as a result of these interactions may cause cytotoxic and genotoxic effects. These results suggest that natural insecticides may also be unreliable for non-target organisms, and the toxic effects of compounds presented as "natural" should also be investigated.

Deep neural network and molecular docking supported toxicity profile of prometryn.

In this study, the versatile toxicity profile of prometryn herbicide on Allium cepa was investigated. In this context, 4 different groups were formed. While the control group was treated with distilled water, Groups II, III and IV were treated with 200 mg/L, 400 mg/L and 800 mg/L prometryn, respectively. After 72 h of germination, cytogenetic, biochemical, physiological and anatomical changes were investigated. As a result increase in malondialdehyde levels, decrease in glutathione level, changes in superoxide dismutase and catalase activities in root tip cells show that prometryn causes oxidative stress. The decrease in mitotic index values and the increase in the frequency of micronucleus and chromosomal abnormalities observed after prometryn treatment indicate genotoxic effects. The genotoxic effects may be due to the induced oxidative stress as well as the promethryn-DNA interaction. Molecular docking analyses revealed that prometryn interacts with various bases in DNA. As a result of the Comet assay, exposure to prometryn was found to cause DNA fragmentation. In physiological parameters final weight, germination percentage and root length decreased by 23.8%, 59.1% and 87.3%, respectively, in the 800 mg/L prometryn applied group. Deep neural network (DNN) model was optimized to predict the effects of different doses of prometryn on 4 different endpoints: micronucleus, mitotic index, chromosomal abnormalities and DNA Damage. The predicted data was found to be very similar to the actual data. The performance of the model was evaluated using MAE, MAPE, RMSE and R2, and these metrics indicate that the model performed well. Overall, the findings of this study suggest that the DNN model developed here is a valuable tool for predicting genotoxicity biomarkers in response to the application doses of prometryn, and has the potential to contribute to the development of safer and more sustainable agricultural practices.