Mutagenic Effects Research Articles

Comparative analysis of colchicine and bio-catharanthine as mutagenic agents for polyploid generation in wild passion fruit (Passiflora foetida)

Wild type Passiflora foetida or a bush passion fruit is unappealing plant with small fruit size (2-3 cm) to be cultivated as a fruit crop. Plant breeding by polyploidization may improve plant production including increase the fruit size. Many researchers have used colchicine as plant chromosome-modifying agent for polyploidization. However, this potent mutagen is very expensive in developing countries and toxic. Hence, an alternative mutagen needs to be considered, such as the natural bio-catharanthine. This study aims to evaluate the effectiveness of colchicine and bio-catharanthine mutagens in polyploidization of P. foetida plants. Experiment was arranged in split-plot design with three replications. Main plot was combination of the mutagens and concentrations, the subplot was soaking durations. Twenty-five seeds each were soaked for 1-, 2- and 3-days in distilled water as control, colchicine (0.05%, 0.1%, 0.15%) and bio-catharanthine (0.5%, 1% and 1.5%) solutions. Result showed, bio-catharanthine concentration of 1% at immersion durations of 3-days and 1.5% at 1-, 2- and 3-days could only produce 89, 56, 74, and 71% grade 1 mixoploid plants accordingly. On the other hand, colchicine succeeded in obtaining tetraploid plants at concentration of 0.15% with 3-days soaking time even though at lower result (5%). Lower colchicine concentrations with shorter or the same soaking period could only produce 5% grade 2 mixoploid plants. Colchicine with one-tenth lower concentration than bio-catharanthine concentration is still more efficient in inducing polyploidy. Further research by involving bio-catharanthine concentration and varying the soaking time must be pursued to obtain higher-level ploidy.

The effect of molnupiravir and nirmatrelvir on SARS-CoV-2 genome diversity in severe models of COVID-19.

Immunocompromised individuals are susceptible to severe COVID-19 and potentially contribute to the emergence of variants with altered pathogenicity due to persistent infection. This study investigated the impact of immunosuppression on SARS-CoV-2 infection in k18-hACE2 mice and the effectiveness of antiviral treatments in this context during the first 7 days of infection. Mice were immunosuppressed using cyclophosphamide and infected with a B lineage of SARS-CoV-2. Molnupiravir and nirmatrelvir, alone and in combination, were administered and viral load and viral sequence diversity was assessed. Treatment of infected but immune compromised mice with both compounds either singly or in combination resulted in decreased viral loads and pathological changes compared to untreated animals. Treatment also abrogated infection of neuronal tissue. However, no consistent changes in the viral consensus sequence were observed, except for the emergence of the S:H655Y mutation. Molnupiravir, but not nirmatrelvir or immunosuppression alone, increased the transition/transversion (Ts/Tv) ratio, representative of A>G and C>U mutations and this increase was not altered by the co-administration of nirmatrelvir with molnupiravir.Notably, immunosuppression itself did not appear to promote the emergence of mutational characteristic of variants of concern (VOCs). Further investigations are warranted to fully understand the role of immunocompromised individuals in VOC development, especially by taking persistence into consideration, and to inform optimised public health strategies. It is more likely that immunodeficiency promotes viral persistence but does not necessarily lead to substantial consensus-level changes in the absence of antiviral selection pressure. Consistent with mechanisms of action, molnupiravir showed a stronger mutagenic effect than nirmatrelvir in this model.

A Nonclinical Safety Evaluation of Cold Atmospheric Plasma for Medical Applications: The Role of Genotoxicity and Mutagenicity Studies.

Atmospheric nonthermal plasma (ANTP) has rapidly evolved as an innovative tool in biomedicine with various applications, especially in treating skin diseases. In particular, the formation of reactive oxygen species (ROS) and nitrogen species (RNS), which are generated by ANTP, plays an important role in the biological signaling pathways of human cells. Unfortunately, excessive amounts of these reactive species significantly result in cellular damage and cell death induction. To ensure the safe application of ANTP, preclinical in vitro studies must be conducted before proceeding to in vivo or clinical trials involving humans. Our study aimed to investigate adverse effects on genetic substances in murine fibroblast cells exposed to ANTP. Cell viability and proliferation were markedly reduced after exposing the cells with plasma. Both extracellular and intracellular reactive species, especially RNS, were significantly increased upon plasma exposure in the culture medium and the cells. Notably, significant DNA damage in the cells was observed in the cells exposed to plasma. However, plasma was not classified as a mutagen in the Ames test. This suggested that plasma led to the generation of both extracellular and intracellular reactive species, particularly nitrogen species, which affect cell proliferation and are also known to induce genetic damage in fibroblast cells. These results highlight the genotoxic and mutagenic effects of ANTP, emphasizing the need for the cautious selection of plasma intensity in specific applications to avoid adverse side effects resulting from reactive species production.

Research Progress on Electrochemical Sensors based on Metal-Organic Framework Materials for the Detection of Mycotoxins in Food

Mycotoxins, with their teratogenic, carcinogenic, and mutagenic effects, pose a significant threat to food safety, socio-economic development, and human health. They are commonly found in cereal crops at concentrations that are difficult to detect, necessitating rapid, sensitive, and accurate detection methods. Metal-Organic Framework (MOF) boasts advantages such as a high specific surface area, high porosity, tunable structures, good conductivity, and stability, making them widely used as excellent metallic materials. Recently, many have made progress in constructing electrochemical sensors based on MOF in combination with metal nanoparticles, porphyrins, polycyclic aromatic hydrocarbons, graphene, etc., for the detection of mycotoxins in food, achieving promising results. In this review, we discuss the harmful effects of mycotoxins, list the regulatory standards for mycotoxins in food set by different organizations and countries, and highlight the methods for detecting common mycotoxins in food using MOF-based electrochemical sensors, providing a reference for subsequent detection of mycotoxins in food.

Effects of mesterolone on the sex ratio, physiology and liver function of juvenile tambaqui (Colossoma macropomum)

In fish, sex dimorphism generates benefits for farming when one gender displays better production traits than the other. In such cases, farming exclusively one sex becomes more profitable. The tambaqui (Colossoma macropomum) is the Brazilian native species with the highest production in the Brazilian fish industry. In tambaqui farming, it is more lucrative to produce females because they grow faster than males. As the species has the XX/XY genetic sex determination system, the use of XX neomales (masculinized genetic females) as breeders to produce solely all-female populations is the most sustainable approach. With the aim of obtaining tambaqui neomales, we tested three doses of mesterolone (1-α-methylandrosterone; at 10, 20 and 40 mg kg−1) through the diet of pre-differentiated juveniles for three months, to masculinize the females. The sex ratio and immediate and long-term effects on the physiology of the fish were evaluated by hematological and biochemical analyses of the blood plasma at the end of the treatment, and three months later. Possible hepatotoxic and mutagenic effects of mesterolone were assessed via liver histopathology, hepatic enzyme production and the micronucleus test (fragmented DNA) in the erythrocytes. The results indicate that 20 and 40 mg kg−1 of mesterolone produced over 76% phenotypic males, have no influence on growth and on the biochemical parameters, do not cause DNA damage, nor do they have toxic effects in the liver of tambaqui. A decrease in the hepatosomatic index and an increase in some hematological parameters were observed during the treatment, but all values were similar to the control three months after the end of the experiment.

Selenium-Doped Biochar for Removal of Anionic Acid Red and Cationic Crystal Violet Dye

The environmental impact of untreated dye effluent is a concern due to potential mutagenic and allergic effects. This study aims to develop a cost-effective selenium-doped biochar as an adsorbent material to remove acid red (AR) and crystal violet (CV) dyes from water. Selenium nanoparticles (SeNPs) were produced using chemical and biological synthesis methods. The SEM, EDX, XRD, FTIR, and BET surface analysis methods were used to characterize the biochar and selenium-doped biochar (Se-AC and BSe-AC) samples. Surface modification with SeNPs resulted in an increase in surface area to 14.560[Formula: see text]m2/g for Se-AC and 85.456[Formula: see text]m2/g for BSe-AC. Different adsorption isotherms (Langmuir, Freundlich, and Temkin) and adsorption kinetic models (pseudo-firstorder, pseudo-secondorder, and intra-particle diffusion kinetics) were investigated to understand the adsorption patterns of biochar, Se-AC, and BSe-AC. The maximum adsorption capacities of biochar, Se-AC, and BSe-AC for AR and CV dye were found to be between 0.48[Formula: see text]mg[Formula: see text]g[Formula: see text] and 7.51[Formula: see text]mg[Formula: see text]g[Formula: see text], 2.31[Formula: see text]mg[Formula: see text]g[Formula: see text] and 7.86[Formula: see text]mg[Formula: see text]g[Formula: see text], and 6.88[Formula: see text]mg[Formula: see text]g[Formula: see text] and 9.09[Formula: see text]mg[Formula: see text]g[Formula: see text], respectively, at 313[Formula: see text]K. The obtained negative [Formula: see text] indicates effective adsorption, while a positive [Formula: see text] suggests an endothermic reaction for both dyes. BSe-AC is an eco-friendly alternative to biochar for removing AR and CV.

Amantadine mitigates the cytotoxic and genotoxic effects of doxorubicin in SH-SY5Y cells and reduces its mutagenicity

Amantadine (AMA) is a useful drug in neuronal disorders, but few studies have been performed to access its toxicological profile. Conversely, doxorubicin (Dox) is a well-known antineoplastic drug that has shown neurotoxic effects leading to cognitive impairment. The aims of this study are to evaluate the cytotoxic, genotoxic, and mutagenic effects of AMA, as well as its possible protective actions against deleterious effects of Dox. The Salmonella/microsome assay was performed to assess mutagenicity while cytotoxicity and genotoxicity were evaluated in SH-SY5Y cells using MTT and comet assays. Possible modulating effects of AMA on the cytotoxicity, genotoxicity, and mutagenicity induced by Dox were evaluated through cotreatment procedures. Amantadine did not induce mutations in the Salmonella/microsome assay and decreased Dox-induced mutagenicity in the TA98 strain. AMA reduced cell viability and induced DNA damage in SH-SY5Y cells. In cotreatment with Dox, AMA attenuated the cytotoxicity of Dox and showed an antigenotoxic effect. In conclusion, AMA does not induce gene mutations, although it has shown a genotoxic effect. Furthermore, AMA decreases frameshift mutations induced by Dox as well as the cytotoxic and genotoxic effects of Dox in SH-SY5Y cells, suggesting that AMA can interfere with Dox mutagenic activity and attenuate its neurotoxic effects.

Design and synthesis of large Stokes shift DNA dyes with reduced genotoxicity

Despite intensive search over the past decades, only a few small-molecule DNA fluorescent dyes were found with large Stokes shifts. These molecules, however, are often too toxic for widespread usage. Here, we designed DNA-specific fluorescent dyes rooted in benzimidazole architectures with a hitherto unexplored molecular framework based on thiazole-benzimidazole scaffolding. We further incorporated a pyrazole ring with an extended sidechain to prevent cell penetration. These novel benzimidazole derivatives were predicted by quantum calculations and subsequently validated to have large Stokes shifts ranging from 135 to 143 nm, with their emission colors changed from capri blue for the Hoechst reference compound to iguana green. These readily-synthesized compounds, which displayed improved DNA staining intensity and detection limits along with a complete loss of capability for cellular membrane permeation and negligible mutagenic effects as designed, offer a safer alternative to the existing high-performance small-molecule DNA fluorescent dyes.

Potential degradation efficiency of Chlorella vulgaris towards methamidophos and diazinon

Pesticides are chemical substances that have become essential for global food production. However, their extensive use has resulted in significant environmental and health costs. Among the most widely used are diazinon and methamidophos, an insecticide and acaricide, respectively. These chemicals are classified as highly hazardous with high toxicity upon contact, ingestion, and inhalation. They are known to cause mutagenic effects, cancer, damage to the endocrine and nervous systems of humans, and their high solubility makes them likely to be found in soil, water, air, and certain foods. In this research, we evaluated the use of the microalga Chlorella vulgaris for phycoremediation of these two pesticides. The first step was to establish and optimize the growth parameters of C. vulgaris to maintain the microalgae in a state of reproduction. Favorable results were obtained at pH 7.0, a dilution ratio of 1:2 for the culture medium, and a photoperiod of 12 h of light and 12 h of darkness. Subsequently, the Minimum Inhibitory Concentration (MIC) and the Half-Maximal Effective Concentration (EC50) of the pesticides diazinon and methamidophos were evaluated. The microalga exhibited a high tolerance rate, with concentrations exceeding those naturally found in the environment. Based on these results, the conditions for assessing the biodegradation of both pesticides by the microalga were established. The outcome showed degradation percentages of 96 % for diazinon (25 mg L−1) and 100 % for methamidophos (500 mg L−1). In addition, the analysis of intermediate metabolites during the biodegradation process of both pesticides revealed the formation of less toxic compounds compared to the precursors and possibly complete mineralization as well; this given the positive response in terms of inorganic phosphate generation during the degradation. Finally, we propose biodegradation pathways for methamidophos and diazinon based on the detected metabolites and available information on biodegradation by certain bacteria.

Induction of genetic diversity in gepak kuning soybean cultivar and M.1.1.3 line using ethyl methane sulfonate in M1 generation

Abstract Genetic diversity is the main determining factor in plant breeding activities. Various breeding methods can be used to induce plant variability, including mutation breeding. The chemical mutagen commonly used for mutagenesis is Ethyl Methane Sulfonate (EMS). This study explores the effects of EMS mutagen on the morphological and agronomic diversity of gepak kuning cultivar and M.1.1.3 soybean line. The research was conducted in Tambon Tunong Village, North Aceh District, Indonesia, using a single-factor Randomized Block Completely Design (RCBD). Concentrations of 0%, 0.05%, 0.075%, and 0.1% EMS were tested on the gepak kuning cultivar and M.1.1.3 line. Treating gepak kuning soybeans with EMS significantly impacted various variables, including harvesting age, pod number, seed weight, leaf appearance, and production. Additionally, the treatment resulted in changes in the morphology of the plant, particularly in the shape of its branches. The EMS treatment on M.1.1.3 line also significantly affected various variables like plant height, flowering age, harvesting age, and yield components. However, it led to sterile plants in the line.

Highly sensitive detection of fluorescent whitening agents in flour using sheathless capillary electrophoresis-electrospray ionization-tandem mass spectrometry

Fluorescent whitening agents (FWAs) are dyes that emit visible blue or blue-purple fluorescence upon ultraviolet-light absorption. Taking advantage of light complementarity, FWAs can compensate for the yellow color of many substances to achieve a whitening effect; thus, they are used extensively in various applications. FWAs are generally stable, but their presence in the environment can lead to pollution and accumulation in the body through the food chain. Recent studies have revealed that some types of FWAs, such as coumarin-based FWAs, may exhibit photo-induced mutagenic effects that can trigger allergic reactions in humans and even pose carcinogenic risks. Hence, the development of an accurate and highly sensitive method for detecting FWAs in food-related samples is a crucial endeavor. Owing to the high polarity and structural similarity of FWAs, the accurate determination of these substances in complex food samples requires an analytical method that offers both efficient separation and sensitive detection. Capillary electrophoresis (CE) exhibits essential features such as high separation efficiency, short analysis times, very small sample injection requirements, minimal use of organic solvents, and simple operation. Thus, it is often used as an effective alternative to liquid chromatographic techniques. Over the past few decades, electrospray ionization mass spectrometry (ESI-MS) has been utilized as a highly sensitive and accurate detection method in numerous chemical analytical fields because it enables the analysis of molecular structures. By combining the high separation efficiency of CE with the high sensitivity of ESI-MS, a powerful tool for identifying and quantifying trace amounts of FWAs in food samples may be obtained. In this study, we present a method based on sheathless CE coupled with electrospray ionization tandem mass spectrometry (ESI-MS/MS) for the simultaneous detection of six trace FWAs in flour. In the proposed method, the CE separation device is directly coupled to the mass spectrometer through a sheathless interface without the need for a sheath liquid for electric contact, thereby avoiding the dilution of the analytes and improving detection sensitivity. Various conditions that could affect extraction recovery, separation efficiency, and detection sensitivity were evaluated and optimized. The FWAs were effectively extracted from the sample matrix with reduced matrix effects by ultrasonic-assisted extraction at a temperature of 30 ℃ for 20 min using CHCl3-MeOH (3∶2, v/v) as the extraction solvent. The extract was centrifuged, dried under N2, and reconstituted in CHCl3-MeOH (1∶4, v/v) for subsequent analysis. During the detection process, the CE device was coupled to the ESI-MS/MS instrument via a highly sensitive porous spray needle, which served as the sheathless electrospray interface. The target FWAs were scanned in positive-ion mode (ESI+) to ensure the stability and intensity of the obtained signals. Additionally, multiple-reaction monitoring (MRM) mode and MS/MS analysis were used to simultaneously quantify the six targets with high selectivity. The developed sheathless CE-ESI-MS/MS method detected the FWAs with high sensitivity over wide linear ranges with low method limits of detection (0.04-0.67 ng/g). The recoveries of the six target FWAs at three spiked levels were between 77.5% and 97.2%, with good interday (RSD≤11.5%) and intraday (RSD≤10.2%) precision. Analyses of the six target FWAs in eight commercial flour samples were performed using this method, and four positive samples were identified. These results demonstrate that the proposed CE-ESI-MS/MS method is a promising strategy for the determination of trace FWAs in complex food sample matrices with efficient separation and high sensitivity.

A Review on Toxicity and Degradation of Ethidium Bromide (EtBr)

Ethidium bromide (EtBr) serves as an interpolating agent utilized for its fluorescent properties in gel electrophoresis, aiding in the detection of various DNA fragments. However, its usage has been associated with DNA mutations, inhibition of mitochondrial protein synthesis and other alterations, particularly at high concentrations. Due to its remarkable stability in the environment and propensity to degrade into mutagenic compounds, especially when exposed to bleaching agents, there are significant concerns regarding its widespread use. Given the potential toxic and mutagenic effects of EtBr and the possibility of its entry into the food chain, it becomes crucial to monitor its concentration at emission sources across different ecosystems, including aquatic, terrestrial, and plant environments. Improper disposal of EtBr poses substantial risks, including the induction of mutations and cancer. Various disposal methods have been explored, such as phytoremediation and employing bacteria capable of degrading this chemical. Proper management of EtBr disposal is paramount to mitigate its harmful impact on the environment and living organisms.

Patulin alters alpha-adrenergic receptor signalling and induces epigenetic modifications in the kidneys of C57BL/6 mice

Patulin (PAT) is a food-borne mycotoxin produced by Penicillium and Byssochlamys species. It is widely known for its mutagenic, carcinogenic, and genotoxic effects and has been associated with kidney injury; however, the mechanism of toxicity remains unclear. To address this gap, we conducted a study to explore the changes in α-adrenergic receptor signalling pathways and epigenetic modifications induced by PAT in the kidneys of C57BL/6 mice during acute (1 day) and prolonged (10 days) exposure. The mice (20–22 g) were orally administered PAT (2.5 mg/kg; at 1 and 10 days), and post-treatment, the kidneys were harvested, homogenised and extracted for RNA, DNA, and protein. The relative gene expression of the α-adrenergic receptors (ADRA1, ADRA2A, ADRA2B) and associated signalling pathways (MAPK, MAPK14, ERK, PI3K, and AKT) was assessed by qPCR. The protein expression of ERK1/2 and MAPK was determined by western blot. The impact of PAT on DNA methylation was evaluated by quantifying global DNA methylation; qPCR was used to determine gene expression levels of DNA methyltransferases (DNMT1, DNMT3A, and DNMT3B) and demethylase (MBD2). PAT downregulated the expression of ADRA1, ADRA2A, ADRA2B, PI3K, and AKT and upregulated ERK1/2 and MAPK protein expression. Furthermore, PAT induced alterations in DNA methylation patterns by upregulating DNMT1 and MBD2 expressions and downregulating DNMT3A and DNMT3B expressions, resulting in global DNA hypomethylation. In conclusion, PAT disrupts α-1 and α-2 adrenergic receptor signalling pathways and induces epigenetic modifications, that can lead to kidney injury.

Oral Administration of a Specific p300/CBP Lysine Acetyltransferase Activator Induces Synaptic Plasticity and Repairs Spinal Cord Injury.

TTK21 is a small-molecule activator of p300/creb binding protein (CBP) acetyltransferase activity, which, upon conjugation with a glucose-derived carbon nanosphere (CSP), can efficiently cross the blood-brain barrier and activate histone acetylation in the brain. Its role in adult neurogenesis and retention of long-term spatial memory following intraperitoneal (IP) administration is well established. In this study, we successfully demonstrate that CSP-TTK21 can be effectively administered via oral gavage. Using a combination of molecular biology, microscopy, and electrophysiological techniques, we systematically investigate the comparative efficacy of oral administration of CSP and CSP-TTK21 in wild-type mice and evaluate their functional effects in comparison to intraperitoneal (IP) administration. Our findings indicate that CSP-TTK21, when administered orally, induces long-term potentiation in the hippocampus without significantly altering basal synaptic transmission, a response comparable to that achieved through IP injection. Remarkably, in a spinal cord injury model, oral administration of CSP-TTK21 exhibits efficacy equivalent to that of IP administration. Furthermore, our research demonstrates that oral delivery of CSP-TTK21 leads to improvements in motor function, histone acetylation dynamics, and increased expression of regeneration-associated genes (RAGs) in a spinal injury rat model, mirroring the effectiveness of IP administration. Importantly, no toxic and mutagenic effects of CSP-TTK21 are observed at a maximum tolerated dose of 1 g/kg in Sprague-Dawley (SD) rats via the oral route. Collectively, these results underscore the potential utility of CSP as an oral drug delivery system, particularly for targeting the neural system.

Emerging innovative pre‐ and post‐harvest management practices to mitigate patulin‐linked food safety risks in apple and its products

AbstractPatulin, a toxic secondary metabolite produced by certain molds (Penicillium, Aspergillus, and Byssochlamys), poses a significant health risk when present in apple juice products above permissible levels. Its presence is a major concern for both consumers and regulatory bodies due to its potential carcinogenic and mutagenic effects. Minimizing patulin concentration in apple juice products requires a multifaceted approach involving various stages of apple fruit production, from orchard management to processing and storage. This review explores the pre‐ and postharvest strategies associated with minimizing patulin concentration in apple juice products. It examines the role of good agricultural practices in reducing mold contamination in orchards and discusses the importance of proper postharvest handling, including fruit sorting and washing to remove contaminated apples before processing. During processing, factors such as temperature, pH, and processing time play crucial roles in minimizing patulin levels. Innovative processing technologies, such as pulsed electric fields (PEF), ultraviolet (UV) radiation, high‐pressure processing, enzymatic, and chemical degradation have shown promise in reducing patulin concentration while preserving the sensory and nutritional quality of the juice. Furthermore, effective storage practices, such as maintaining proper temperature and humidity levels, are essential for preventing patulin formation during storage. Continuous monitoring and analytical testing for patulin content throughout the production chain are necessary to ensure compliance with regulatory standards and to guarantee the safety of apple juice products. Despite advancements in technology and production practices, challenges remain in effectively minimizing patulin concentration. These include the need for further research to develop more efficient detection methods, the adoption of sustainable and eco‐friendly practices in orchard management, and the dissemination of knowledge and best practices to stakeholders across the apple juice supply chain. In conclusion, minimizing patulin concentration in apple juice products requires a holistic approach that integrates preventive measures, innovative processing technologies, and stringent quality control measures. By addressing these challenges, the apple juice industry can ensure the production of safe and high‐quality products that meet regulatory standards and consumer expectations.

Hematological and genotoxic biomarkers in a natural population of freshwater turtles Trachemys dorbigni (Duméril & Bibron, 1835) (Testudines: Emydidae) living in an urban area in Southern Brazil.

The present study aimed to report the morphometric and hematological indices and genotoxicity of a free-life population of D'Orbigny's slider turtles (Trachemys dorbigni) living in an urban area in Southern Brazil. For that, 16 specimens were randomly captured in an urban canal that receives irregular releases of wastewater. Biometrics and external visual changes were analyzed, such as turtle shell deformities, and the presence of parasites. Blood samples were collected to evaluate the hematological profile and the presence of micronuclei and other erythrocyte nuclear abnormalities as potential mutagenic and genotoxic effects. Water physicochemical parameters were also measured. Organisms with ectoparasites (31.25%) and small carapace deformations (56.25%) were observed, but maximum carapace length and weight were considered normal for the species according to the literature. The blood profile indicated low hemoglobin and hematocrit and a high number of total leukocytes, particularly eosinophils which characterize parasitic infections. A frequency of 0.12% for the micronucleus was considered basal, but the frequency of other erythrocyte abnormalities was evident, mainly of blebbed nuclei (63.79%), indicating chromosomal damage in the early stage. The results of this study suggest that natural populations of chelonian inhabiting urbanized areas are impacted by anthropogenic activities in the surrounding environment. Furthermore, it provides comprehensive data which can serve as a comparative model for environmental monitoring studies involving turtles.

The natural anthraquinone dye emodin: Eco/genotoxicological characterization for aquatic organisms

Emodin is an anthraquinone secondary metabolite produced by several species of plants and fungi. Emodin is known for its pharmacological versatility, and, in the textile industry, for its good dyeing properties. However, its use in the textile industry can result in the formation and disposal of large volumes of wastewater. Emodin mutagenicity has been shown in bacteria and in human cells, but little is known about its possible toxic, genotoxic, or mutagenic effects in aquatic organisms. We have evaluated the eco/genotoxicity of emodin to aquatic organisms. Emodin was toxic to Daphnia similis (EC50 = 130 μg L−1) and zebrafish embryos (LC50 = 25 μg L−1). No toxicity was observed for Raphidocelis subcapitata, Ceriodaphnia dubia, or Parhyale hawaiensis. Additional biochemistry/molecular studies are needed to elucidate the toxic/mutagenic pathways of emodin in aquatic organisms. The PNEC value for emodin was 0.025 μg L−1. In addition to mutagenicity in the Salmonella/microsome assay, emodin was mutagenic in the micronucleus assay in the amphipod P. hawaiensis. Among the anthraquinone dyes tested to date, natural or synthetic, emodin was the most toxic to aquatic species.

Synthesis and characterization of iron oxide nanoparticles from Lawsonia inermis and its effect on the biodegradation of crude oil hydrocarbon.

Crude oil hydrocarbons are considered major environmental pollutants and pose a significant threat to the environment and humans due to having severe carcinogenic and mutagenic effects. Bioremediation is one of the practical and promising technology that can be applied to treat the hydrocarbon-polluted environment. In this present study, rhamnolipid biosurfactant (BS) produced by Pseudomonas aeruginosa PP4 and green synthesized iron nanoparticles (G-FeNPs) from Lawsonia inermis was used to evaluate the biodegradation efficiency (BE) of crude oil. The surface analysis of G-FeNPs was carried out by using FESEM and HRTEM to confirm the size and shape. Further, the average size of the G-FeNPs was observed around 10nm by HRTEM analysis. The XRD and Raman spectra strongly confirm the presence of iron nanoparticles with their respective peaks. The BE (%) of mixed degradation system-V (PP4+BS+G-FeNPs) was obtained about 82%. FTIR spectrum confirms the presence of major functional constituents (C=O, -CH3, C-O, and OH) in the residual oil content. Overall, this study illustrates that integrated nano-based bioremediation could be an efficient approach for hydrocarbon-polluted environments. This study is the first attempt to evaluate the G-FeNPs with rhamnolipid biosurfactant on the biodegradation of crude oil.

PAHs in franciscana dolphins from the Southwestern Atlantic Ocean: Concentration and maternal transfer assessments

Polycyclic aromatic hydrocarbons (PAHs) are organic compounds ubiquitous in the environment and known for their toxic, mutagenic, and carcinogenic effects. These compounds can bioaccumulate in the biota and be transferred through trophic webs. The franciscana dolphin (Pontoporia blainvillei), as top predators, can be an environmental sentinels. Thus, this study aimed to provide data about PAHs concentration in their hepatic tissue collected on the coast of Espírito Santo (Franciscana Management Area, FMA Ia), Rio de Janeiro (FMA IIa), and São Paulo states (FMA IIb), in Southeastern Brazil. PAHs were detected in 86 % of franciscana dolphins (n = 50). The highest ∑PAHsTotal median concentration was reported in FMA Ia followed by FMA IIb and FMA IIa (1055.6; 523.9, and 72.1 ng.g-1 lipid weight, respectively). Phenanthrene was detected in one fetus and two neonates, showing maternal transfer of PAHs in these dolphins. Evaluating PAHs with potential toxic effects is of utmost importance for the conservation of a threatened species.

Effects of pH-varying thermal modification on sewage sludge: A focus on releasing nitrogen- and phosphorus-containing substances

Sewage sludge is promising for the recovery and utilisation of nutrient components, but its complex nature hinders the release of these components. The combination of pH and thermal modifications shows promise for the release of nutrient components from sludge. However, comprehensive studies on the full spectrum of pH levels and corresponding mechanisms of pH-varying thermal modification are lacking. In this study, the main nutrient components, physicochemical properties, molecular structure, and noncovalent interactions of sludge were comprehensively investigated through pH-varying thermal modification (within a pH range of 2.0 to 12.0 under the same thermal condition). The experimental results showed that the release of main organics, particularly nitrogen (N)-containing organics, was well-fitted, with a tick-like function (R2: 0.74–0.96). The thermal protons exhibited a notable accumulative mutagenic effect on the N-containing organics release, while the thermal hydroxyl ions had a more direct effect, as revealed by the changes in multivalent metals and molecular structures with the protonation–deprotonation of carboxyl groups. The driving force for the release of N-containing organics was identified as the fluctuation of electrostatic interactions at the solid–liquid interface of the sludge. However, the release of phosphorus (P)-containing substances exhibited a contrasting response to that of N-containing substances with varying pH, likely because the reaction sites of thermal protons and thermal hydroxyl ions for P-containing substances were different. Moreover, high concentrations of thermal protons and hydroxyl ions collapsed the Lifshitz–van der Waals interactions of sludge, resulting in a decrease in viscoelasticity and binding strength. These propositions were further confirmed through statistical analyses of the main indicators of the main nutrient components, physicochemical properties, and noncovalent interactions of sludge. These findings can provide a basis for optimising characteristic-specific methods to recovery nutrient components (N/P) from sludge.