Enantioselective toxicity assessment of prothioconazole on earthworms (Eisenia foetida) in artificial soil environments

The chiral fungicide prothioconazole (PTZ) is extensively employed in agricultural practices, prompting serious concern due to its environmental impact. PTZ is prone to undergo metabolism, leading to the formation of chiral prothioconazole-desthio (dPTZ) in the environment. However, limited knowledge exists regarding its enantioselective behavior and toxicity towards invertebrate organisms in soil ecosystems. In this study, R-(-)- and S-(+)- PTZ enantiomers were individually synthesized, and their stereoselective toxicity effects on earthworms (E. foetida) were studied in artificial soil under environmentally relevant concentration exposures. The results showed a significant accumulation of dPTZ in earthworms, surpassing the levels of PTZ. Moreover, the concentration of S-(-)- dPTZ in earthworms was notably higher than that of R-(+)- dPTZ after exposure, reaching peak levels on day 14. Concurrently, oxidative stress induced by S-(+)- PTZ enantiomers in earthworms exhibited a substantial increase compared to R-(-)- enantiomers on day 14, indicating a higher ecological risk associated with the former in non-target organisms. Transcriptome analysis unveiled distinct impacts on earthworm physiology. S-(+)-PTZ exposure significantly affected energy metabolism, immune responses and digestive systems. In contrast, R-(-)-PTZ exposure influenced the synthesis of carbohydrates, proteins, and lipids. These insights contribute to understanding the complex interactions between PTZ enantiomers and soil-dwelling organisms, providing a scientific foundation for advancing the application of high efficiency, low toxicity PTZ monomer pesticides.

Mechanisms of Biological Effects of Ionic Liquids: From Single Cells to Multicellular Organisms

The review presents a detailed discussion of the evolving field studying interactions between ionic liquids (ILs) and biological systems. Originating from molten salt electrolytes to present multiapplication substances, ILs have found usage across various fields due to their exceptional physicochemical properties, including excellent tunability. However, their interactions with biological systems and potential influence on living organisms remain largely unexplored. This review examines the cytotoxic effects of ILs on cell cultures, biomolecules, and vertebrate and invertebrate organisms. Our understanding of IL toxicity, while growing in recent years, is yet nascent. The established findings include correlations between harmful effects of ILs and their ability to disturb cellular membranes, their potential to trigger oxidative stress in cells, and their ability to cause cell death via apoptosis. Future research directions proposed in the review include studying the distribution of various ILs within cellular compartments and organelles, investigating metabolic transformations of ILs in cells and organisms, detailed analysis of IL effects on proteins involved in oxidative stress and apoptosis, correlation studies between IL doses, exposure times and resulting adverse effects, and examination of effects of subtoxic concentrations of ILs on various biological objects. This review aims to serve as a critical analysis of the current body of knowledge on IL-related toxicity mechanisms. Furthermore, it can guide researchers toward the design of less toxic ILs and the informed use of ILs in drug development and medicine.

Density Functional Method Study on the Cooperativity of Intermolecular H-bonding and π-π+ Stacking Interactions in Thymine-[Cnmim]Br (n = 2, 4, 6, 8, 10) Microhydrates

The exploration of the ionic liquids’ mechanism of action on nucleobase’s structure and properties is still limited. In this work, the binding model of the 1-alkyl-3-methylimidazolium bromide ([Cnmim]Br, n = 2, 4, 6, 8, 10) ionic liquids to the thymine (T) was studied in a water environment (PCM) and a microhydrated surroundings (PCM + wH2O). Geometries of the mono-, di-, tri-, and tetra-ionic thymine (T-wH2O-y[Cnmim]+-xBr−, w = 5~1 and x + y = 0~4) complexes were optimized at the M06-2X/6-311++G(2d, p) level. The IR and UV-Vis spectra, QTAIM, and NBO analysis for the most stable T-4H2O-Br−-1, T-3H2O-[Cnmim]+-Br−-1, T-2H2O-[Cnmim]+-2Br−-1, and T-1H2O-2[Cnmim]+-2Br−-1 hydrates were presented in great detail. The results show that the order of the arrangement stability of thymine with the cations (T-[Cnmim]+) by PCM is stacking > perpendicular > coplanar, and with the anion (T-Br−) is front > top. The stability order for the different microhydrates is following T-5H2O-1 < T-4H2O-Br−-1 < T-3H2O-[Cnmim]+-Br−-1 < T-2H2O-[Cnmim]+-2Br−-1 < T-1H2O-2[Cnmim]+-2Br−-1. A good linear relationship between binding EB values and the increasing number (x + y) of ions has been found, which indicates that the cooperativity of interactions for the H-bonding and π-π+ stacking is varying incrementally in the growing ionic clusters. The stacking model between thymine and [Cnmim]+ cations is accompanied by weaker hydrogen bonds which are always much less favorable than those in T-xBr− complexes; the same trend holds when the clusters in size grow and the length of alkyl chains in the imidazolium cations increase. QTAIM and NBO analytical methods support the existence of mutually reinforcing hydrogen bonds and π-π cooperativity in the systems.

Comparative toxicity of [C8mim]Br and [C8py]Br in early developmental stages of zebrafish (Danio rerio) with focus on oxidative stress, apoptosis, and neurotoxicity

The increasing production and usage of ionic liquids (ILs) have raised global ecotoxicological concerns regarding their release into the environment. While the effects of side chains on the IL-induced toxicity in various aquatic organisms have been well-recognized, the role of cationic cores in determining their ecotoxicity remains to be elucidated. Herein, the comparative bioavailability and toxicity of two ILs with different cationic cores but the same anion and side chain in zebrafish embryos were determined. 1-octyl-3-methylimidazolium bromide ([C8mim]Br) has higher accumulation in zebrafish, and triggered developmental toxicity by inducing oxidative stress and apoptosis. Meanwhile, 1-octyl-1-methylpyridium bromide ([C8py]Br) enhanced SOD activity and upregulated anti-apoptotic bcl-2 gene expression, contributing to its much lower neurodevelopmental toxicity. Our study demonstrates the vital role of cationic core in determining the developmental toxicity of ILs and highlights the need for further investigations into the toxicity of imidazolium and pyridinium based ILs in aquatic ecosystems.

Phthalate induced oxidative stress and DNA damage in earthworms (Eisenia fetida)

Phthalates (phthalic acid esters) have been widely applied as plasticizers. They are ubiquitous contaminants in soils, thereby posing a threat to human health. In this study, ecotoxicological effects of three typical PAEs (dimethyl phthalate-DMP, di-n-octyl phthalate-DOP and butyl benzyl phthalate-BBP) were investigated. As a biological indicator, earthworms (Eisenia fetida) were exposed to phthalates at various doses (0, 0.1, 1, 10 and 50 mg/kg) for different times (7, 14, 21, and 28 d). We evaluated the effects of phthalates on reactive oxygen species (ROS) generation, antioxidant enzymes (superoxide dismutase-SOD, peroxidase-POD and catalase-CAT) activities, glutathione S-transferase enzyme (GST) activity, malondialdehyde (MDA) content and DNA damage. Results showed that ROS content increased with increasing phthalates, whereas ROS content generally increased and then decreased with exposure time. However, antioxidant enzymes activities in earthworms displayed different trends. The GST activity in high-dose treatment group was significantly activated. For DMP and DOP, lipid peroxidation mainly occurred between 14 and 28 d, while for BBP, it primarily existed after 7 d and then disappeared after 28 d. Besides, comet assay indicated that there was a dose-response relationship between the DNA damage and phthalate dose, following DMP > DOP > BBP. Given their toxicity, it is important to understand the mechanisms associated with their eco-toxicity and to reduce their adverse impacts on the environment.

Ecotoxicological effects of fertilizers made from pulping waste liquor on earthworm Eisenia fetida

In recent years, increasing efforts have focused on production of organic-inorganic compound fertilizers using ammonium sulfite pulping waste liquor. However, their ecological effects on soil have not been studied. In this study, earthworm Eisenia fetida was exposed to various doses (0, 0.13, 0.26 and 0.52 kg/m²) for different time (7, 14, 21, and 28 d) to evaluate the effects of fertilizers made from pulping waste liquor, including reactive oxygen species (ROS) generation, antioxidant enzymes activities, glutathione S-transferase enzyme (GST) activity, malondialdehyde (MDA) content and DNA damage. Results showed that there were significant increase of ROS and MDA levels after 14 d, inducing production of antioxidant enzymes (superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT)) as well as GST. Before 14 d, excess ROS and MDA caused damage to the DNA of earthworms, leading to gradual increase of Olive tail moment (OTM) in the comet assay. With the exposure time extended to 28 d, owing to the combined effects of elimination of free radicals by antioxidant enzymes and detoxification enzymes as well as self-repairing function of cells, ROS and MDA levels declined slightly and OTM gradually decreased. In summary, this study indicated that there was a toxicological effect on earthworms when fertilizers made from pulping waste liquor were applied to soil, which needs more attention.

Exposed zebrafish (Danio rerio) to imidazolium-based ionic liquids with different anions and alkyl-chain lengths

Ionic liquids (ILs) were considered new "green solvents" in consideration of the low volatility. Since their inception, ionic liquids (ILs) have attracted widespread attention. However, ILs were not safe enough as what we thought. The toxicity of 1-ethyl-3-methylimidazolium ILs ([C₂mim]R, R = Cl^-, Br^-, BF₄^-) and 1-alkyl-3-methylimidazolium bromine ([C_nmim]Br, n = 2, 4, 8, 10, 12) using 50% lethal concentration (LC₅₀) were studied in the present study to enrich the toxicological information. Besides the LC₅₀ values, the sensitivity test using potassium dichromate (K₂Cr₂O₇) and residue determinations of the tested ILs were also performed. The sensitivity and dynamic changes of IL doses both catered for the stipulation that declared the accuracy of the toxicological test results, which illustrated that the alkyl-chain lengths contributed more than anions to the toxicity of the ILs described above to zebrafish. Additionally, the present study also enriched the toxicological information on imidazolium-based ILs to aquatic systems.

The acute toxic effects of 1-alkyl-3-methylimidazolium nitrate ionic liquids on Chlorella vulgaris and Daphnia magna

Given their increasingly widespread application, the toxic effects of ionic liquids (ILs) have become the subject of significant attention in recent years. Therefore, the present study assessed the acute toxic effects of 1-alkyl-3-methylimidazolium nitrate ([C_nmim]NO₃ (n = 2, 4, 6, 8, 10, 12)) on Chlorella vulgaris and Daphnia magna. The sensitivity of the tested organism Daphnia magna and the investigated IL concentrations in water using high-performance liquid chromatography (HPLC) were also evaluated to demonstrate the reliability of the present study. The results illustrated that Daphnia magna is indeed sensitive to the reference toxicant and the investigated ILs were stable in the aquatic environment. The 50% effect concentration (EC₅₀) was used to represent the acute toxic effects on Chlorella vulgaris and Daphnia magna. With the increasing alkyl-chain lengths, the toxicity of the investigated ILs increased in both the test organisms. Accordingly, the alkyl-chain lengths can cause significantly toxic effects on aquatic organisms, and Daphnia magna are much more sensitive than Chlorella vulgaris to the imidazolium-based ILs used in the present study. Furthermore, the present study provides more information on the acute toxic effects of 1-alkyl-3-methylimidazolium nitrate.

The acute toxic effects of imidazolium-based ionic liquids with different alkyl-chain lengths and anions on zebrafish (Danio rerio)

With the increasing applications of ionic liquids (ILs), the toxicity of ILs has drawn increasing attention in recent years, especially the influences of different anions and alkyl-chain lengths on the acute toxicity to aquatic organisms. We performed a study on the acute toxicity of 1-alkyl-3-methylimidazolium nitrate ([C_nmim]NO₃ (n=2, 4, 6, 8, 10, 12)), 1-hexyl-3-methylimidazolium ILs ([C₆mim]R (R=Cl^-, Br^-, BF₄^-, PF₆^-)) to zebrafish (Danio rerio). We also evaluated the sensibility of the investigated animals and the stability of ILs in water via high performance liquid chromatography (HPLC, Agilent 1260, Agilent Technologies Inc., USA) to prove the reliability of the present study. The results illustrated that the test zebrafish (Danio rerio) were sensitive to the reference toxicant and that the investigated ILs in water were stable. The 50% lethal concentration (LC₅₀) was used to represent the acute toxicity to zebrafish (Danio rerio). The present study showed that the highest toxic IL is [C₁₂mim]NO₃ and the lowest toxic IL is [C₂mim]NO₃ on Danio rerio. The LC₅₀s for ILs with different anions had similar values. Accordingly, we believe that ILs with different alkyl-chain lengths cause greater effects than other anions on acute toxicity to aquatic organisms. Furthermore, the present study can also provide scientific methods for future studies to select and assess ILs.

Acute toxicity, biochemical toxicity and genotoxicity caused by 1-butyl-3-methylimidazolium chloride and 1-butyl-3-methylimidazolium tetrafluoroborate in zebrafish (Danio rerio) livers

The present study examined the potential toxicity of 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) and 1-butyl-3- methylimidazolium tetrafluoroborate ([Bmim]BF₄) in the liver cells of zebrafish (Danio rerio) with different doses (20-160mg/L) on 7 and 14days. The effects of [Bmim]Cl and [Bmim]BF₄ on acute toxicity, reactive oxygen species (ROS), antioxidant enzymes, glutathione S-transferase (GST), malondialdehyde (MDA), and DNA damage degree in livers of zebrafish were determined. The 50% lethal concentration (LC₅₀) values after a 96-h exposure to [Bmim]Cl and [Bmim]BF₄ were 632.8±67.4 and 604.6±56.2mg/L, respectively, which indicated that the substances were practically harmless. The minor discrepancy may be caused by the different anions. The ROS levels were dose-dependent, which may cause the inhibition of antioxidant enzyme activity, lipid peroxidation, DNA damage and the stimulation of detoxifying enzyme activity. The present study can also provide scientific support for the future selection and evaluation of ionic liquids (ILs).

Biological Activity of Ionic Liquids and Their Application in Pharmaceutics and Medicine

Ionic liquids are remarkable chemical compounds, which find applications in many areas of modern science. Because of their highly tunable nature and exceptional properties, ionic liquids have become essential players in the fields of synthesis and catalysis, extraction, electrochemistry, analytics, biotechnology, etc. Apart from physical and chemical features of ionic liquids, their high biological activity has been attracting significant attention from biochemists, ecologists, and medical scientists. This Review is dedicated to biological activities of ionic liquids, with a special emphasis on their potential employment in pharmaceutics and medicine. The accumulated data on the biological activity of ionic liquids, including their antimicrobial and cytotoxic properties, are discussed in view of possible applications in drug synthesis and drug delivery systems. Dedicated attention is given to a novel active pharmaceutical ingredient-ionic liquid (API-IL) concept, which suggests using traditional drugs in the form of ionic liquid species. The main aim of this Review is to attract a broad audience of chemical, biological, and medical scientists to study advantages of ionic liquid pharmaceutics. Overall, the discussed data highlight the importance of the research direction defined as "Ioliomics", studies of ions in liquids in modern chemistry, biology, and medicine.