Effect of Melissa officinalis L. leaf extract on manganese-induced cyto-genotoxicity on Allium cepa L.

Although the antioxidant properties of Melissa officinalis extract (Mox) are widely known, little work has focused on its protective capacity against heavy metal stress. The primary objective of this study was to determine the potential of Mox to mitigate manganese (II) chloride (MnCI2)-induced cyto-genotoxicity using the Allium and comet assays. Physiological, genotoxic, biochemical and anatomical parameters as well as the phenolic composition of Mox were examined in Allium cepa (L.). Application of 1000 µM MnCl2 reduced the rooting percentage, root elongation, weight gain, mitotic index and levels of chlorophyll a and chlorophyll b pigments compared to the control group. However, it increased micronuclei formation, chromosomal abnormality frequencies, tail DNA percentage, proline amount, lipid peroxidation level and meristematic damage severity. The activities of superoxide dismutase and catalase also increased. Chromosomal aberrations induced by MnCl2 were fragment, sticky chromosome, vagrant chromosome, unequal distribution of chromatin and bridge. Application of 250 mg/L Mox and 500 mg/L Mox along with MnCl2 significantly alleviated adverse effects dose dependently. The antioxidant activity bestowed by the phenolic compounds in Mox assisted the organism to combat MnCl2 toxicity. Consequently, Mox exerted remarkable protection against MnCl2 toxicity and it needs to be investigated further as a potential therapeutic option.

Eco-corona formation diminishes the cytogenotoxicity of graphene oxide on Allium cepa: Role of soil extracted-extracellular polymeric substances in combating oxidative stress.

Graphene oxide (GO) is widely acknowledged for its exceptional biological and industrial applications. However, its discharge into the environment negatively impacts the ecosystem. This study aimed to investigate the toxicity of GO in Allium cepa root tip cells and the role of extracellular polymeric substances (EPS) in modulating its toxic effects. To evaluate toxicity, various endpoints like cell viability using Evans blue dye, cytotoxicity (mitotic index), genotoxicity (chromosomal aberrations), and oxidative stress assessments (total ROS, superoxide, hydroxyl radical production, and lipid peroxidation) were considered. The results suggest that pristine GO caused a dose-dependent increase in various toxicity parameters, especially the genotoxic effects. Oxidative stress generation by GO is proposed to be the principal mode of action. The EPS-corona formed on GO could potentially counteract the toxic effects, substantially reducing the oxidative stress within the cells.

Protective effect of quercetin and thymoquinone against genotoxicity and oxidative stress induced by ZnO nanoparticles in the Wistar rat model.

Zinc oxide nanoparticles (ZnO-NPs) are increasingly used in a variety of consumer and other commercial products. Hence, man faces the risk of exposure to ZnO-NPs and the consequent adverse health effects. Mitigation/prevention of such effects using natural products has drawn the attention of scientists. Therefore, the aim of the present study has been to find the toxic effects associated with exposure to ZnO-NPs, and the protective role of the phytochemicals thymoquinone (TQ) and quercetin (QCT) in the rat model. ZnO-NPs were administered to male Wistar rats through oral route; TQ / QCT was concurrently administered through intra-peritoneal route. The response in the animal was analyzed adopting chromosomal aberration test, micronucleus test, and comet assay of bone marrow cells to assess the genotoxicity, and biochemical assays of superoxide dismutase (SOD), catalase (CAT), lipid peroxidation (LPO), total extractable protein of liver, and reduced glutathione (GSH) of liver homogenate to monitor the changes in the antioxidant defense mechanism in response to the oxidative stress. Treatment of 300 mg/kg body weight (bw) of ZnO-NPs produced adverse effects on all aspects analyzed viz., structural chromosomal aberrations, micronuclei formation, DNA damage, SOD, catalase, lipid peroxidation, GSH, and extractable total protein of liver. Co-treatment of TQ / QCT offered protection against the toxicity induced by ZnO-NPs. The most optimum doses of TQ and QCT that offered the best protection were 18 mg/kg bw and 500 mg/kg bw, respectively. The study reveals that TQ / QCT supplementation is beneficial in the context of toxic effects of ZnO-NPs.

DNA fragmentation and multifaceted toxicity induced by high-dose vanadium exposure determined by the bioindicator Allium test.

In this study, the toxicity of vanadium (VCI3) in Allium cepa L. was studied. Germination-related parameters, mitotic index (MI), catalase (CAT) activity, chromosomal abnormalities (CAs), malondialdehyde (MDA) level, micronucleus (MN) frequency and superoxide dismutase (SOD) activity were investigated. The effects of VCI3 exposure on the DNA of meristem cells were investigated with the help of comet assay, and the relationships between physiological, cytogenetic and biochemical parameters were revealed by correlation and PCA analyses. A. cepa bulbs were germinated with different concentrations of VCI3 for 72 h. As a result, the maximum germination (100%), root elongation (10.4 cm) and weight gain (6.85 g) were determined in the control. VCI3 treatment caused significant decreases in all tested germination-related parameters compared to the control. The highest percentage of MI (8.62%) was also observed in the control. No CAs were found in the control, except for a few sticky chromosomes and unequal distribution of chromatin (p > 0.05). VCI3 treatment caused significant decreases in MI and increases in the frequencies of CAs and MN, depending on the dose. Similarly, the comet assay showed that DNA damage scores increased with increasing VCI3 doses. The lowest root MDA (6.50 µM/g) level and SOD (36.7 U/mg) and CAT (0.82 OD240nmmin/g) activities were also measured in the control. VCI3 treatment caused significant increases in root MDA levels and antioxidant enzyme activities. Besides, VCI3 treatment induced anatomical damages such as flattened cell nucleus, epidermis cell damage, binuclear cell, thickening in the cortex cell wall, giant cell nucleus, damages in cortex cell and unclear vascular tissue. All examined parameters showed significant negative or positive correlations with each other. PCA analysis confirmed the relations of investigated parameters and VCI3 exposure.

Monitoring genotoxic, biochemical and morphotoxic potential of penoxsulam and the protective role of European blueberry (Vaccinium myrtillus L.) extract.

The present study aimed at exploring to explore the penoxsulam toxicity and protective effects of blueberry extract in roots of Allium cepa L. The effective concentration (EC50) of penoxsulam was determined at 20 µg/L by the root growth inhibition test as the concentration reducing the root length by 50%. The bulbs of A. cepa L. were treated with tap water, blueberry extracts (25 and 50 mg/L), penoxsulam (20 µg/L) and combination of blueberry extracts (25 and 50 mg/L) with penoxsulam (20 µg/L) for 96 h. The results revealed that penoxsulam exposure inhibited cell division, rooting percentage, growth rate, root length and weight gain in the roots of A. cepa L. In addition, it induced chromosomal anomalies such as sticky chromosome, fragment, unequal distribution of chromatin, bridge, vagrant chromosome and c-mitosis and DNA strand breaks. Further, penoxsulam treatment enhanced malondialdehyde content and SOD, CAT and GR antioxidant enzyme activities. Molecular docking results supported the up-regulation of antioxidant enzyme SOD, CAT and GR. Against all these toxicity, blueberry extracts reduced penoxsulam toxicity in a concentration-dependent manner. The highest amount of recovery for cytological, morphological and oxidative stress parameters was observed when using blueberry extract at a concentration of 50 mg/L. In addition, blueberry extracts application showed a positive correlation with weight gain, root length, mitotic index and rooting percentage whereas a negative correlation with micronucleus formation, DNA damage, chromosomal aberrations, antioxidant enzymes activities and lipid peroxidation indicating its protecting effects. As a result, it has been seen that the blueberry extract can tolerate all these toxic effects of penoxsulam depending on the concentration, and it has been understood that it is a good protective natural product against such chemical exposures.

Assessing the combined toxic effects of metaldehyde mollucide.

The excessive use of metaldehyde in agriculture to combat mollusks endangers both the environment and non-target organisms. The aim of this study is to investigate the toxicity caused by metaldehyde in Allium cepa with the help of physiological, cytogenetic, biochemical and anatomical parameters. Also, DNA fragmentation caused by metaldehyde in root tip cells was measured by the "Comet Assay" method. The control group was germinated with tap water and the application groups were germinated with 20 mg/L metaldehyde, 40 mg/L metaldehyde, 100 mg/L metaldehyde and 200 mg/L metaldehyde for 72 h. The results of the physiological parameters showed that metaldehyde had a growth-limiting effect in A. cepa, depending on the application dose. According to root elongation levels, the EC50 (effective concentration) value for metaldehyde was 60.6 mg/L in A. cepa. As the treatment dose increased, the incidence of micronucleus and chromosomal aberrations gradually increased while mitotic index decreased. Metaldehyde exposure induced damages such as sticky chromosome, fragment, unequal distribution of chromatin, reverse polarization, bridge, and multipolar anaphase. In addition, metaldehyde caused cell damage in epidermis and cortex, thickening of the cortex cell wall and flattened cell nucleus in root meristem. Increasing doses of metaldehyde application also increased malondialdehyde levels, superoxide dismutase and catalase activities. As a result, it has been determined that the toxicity of metaldehyde in plants is versatile and the A. cepa test material is a suitable biological indicator to determine this toxicity.

Evaluation of genotoxicity and 13-week subchronic toxicity of root of Asarum heterotropoides var. seoulense (Nakai) Kitag.

ETHNOPHARMACOLOGICAL RELEVANCE: Asarum heterotropoides var. seoulense (Nakai) Kitag is a traditional herbal medicine used in Korea and China. It is effective in aphthous stomatitis, local anesthesia, headache, toothache, gingivitis, and inflammatory diseases. However, information on the toxicity of the root of Asarum heterotropoides var. seoulense (Nakai) Kitag (AR) is limited. Therefore, preclinical toxicity studies on AR are needed to reduce the risk of excessive intake. AIM OF THE STUDY: We aimed to evaluate genotoxicity and the potential toxicity due to repeated administration of AR powder. MATERIALS AND METHODS: In vitro bacterial reverse mutation assay (Ames), in vitro chromosomal aberration assay (CA), and in vivo micronucleus (MN) assay in ICR mice were conducted. As positive results were obtained in Ames and CA assays, alkaline comet assay and pig-a gene mutation test were conducted for confirmation. For evaluating the general toxicity of AR powder, a 13-week subchronic toxicity test was conducted, after determining the dose by performing a single and a 4-week dose range finding (DRF) test. A total of 152 Sprague-Dawley (SD) rats were orally administered AR powder at doses of 0, 150, 350, 500, 1000, and 2000 mg/kg/day in the 13-week subchronic toxicity test. Hematology, clinical chemistry, urinalysis, organ weight, macro-, and microscopic examination were conducted after rat necropsy. RESULTS: AR powder induced genotoxicity evidenced in the Ames test at 187.5, 750, 375, and 1500 µg/plate of TA100, TA98, TA1537, and E. coli WP2uvrA in the presence and absence of S9, respectively; CA test at 790 µg/mL for 6 h in the presence of S-9; 75 µg/mL for 6 h in the absence of S-9, and 70 µg/mL for 22 h in the absence of S-9 in the stomach in the comet assay but not in MN and pig-a assays. In the 13-week subchronic toxicity study, clinical signs including irregular respiration, noisy respiration, salivation, and decreased body weight or food consumption were observed in males and females in the 2000 mg/kg/day group. In hematology tests, clinical chemistry, urinalysis, organ weight, and macroscopic examination, changes were observed in the dose groups of 500 mg/kg/day and above. Microscopic examination revealed hyperplasia of the stomach as a test-related change. Hepatocellular adenoma and changes in liver-related clinical chemistry parameters were observed. The rat No Observed Adverse Effect Level (NOAEL) was 150 mg/kg/day in males and <150 mg/kg/day in females. CONCLUSIONS: AR powder is potentially toxic to the liver and stomach and should be used with caution in humans. A long-term study on carcinogenicity is necessitated because DNA damage or changes in tissue lesions were observed in SD rats.

Screening the toxicity profile and genotoxicity mechanism of excess manganese confirmed by spectral shift.

In this study, the toxicity induced by excessive doses of manganese (MnCl2), which is one of the essential trace elements for the continuation of the metabolic activities of the organisms, was investigated with the help of the Allium test. Toxicity was investigated by using physiological (percent germination, root length, weight gain), cytogenetic [mitotic index (MI), micronucleus (MN), chromosomal abnormalities (CAs)], biochemical [malondialdehyde (MDA), superoxide dismutase (SOD) catalase (CAT)] and anatomical (root tip meristematic cell damage) parameters. Allium cepa L. bulbs were divided into four groups as one control and three treatments. The control group was germinated with tap water, and the treatment groups were germinated with 250, 500 and 1000 µM doses of MnCl2. The germination process was continued for 72 h without interruption. At the end of the period, the root tips were collected, washed in distilled water and made ready for microscopic and spectrophotometric analyzes with the help of routine preparation techniques. As a result, the highest germination percentage, root length, weight gain and MI, and the lowest MN frequency, CAs numbers, MDA level, SOD and CAT enzyme activities were determined in the control group (group I). MnCl2 exposure caused a decrease in physiological parameter values and an increase in cytogenetic (except MI) and biochemical parameter values, depending on the dose. MnCl2 exposure induced MN and CAs such as fragment, sticky chromosome, vagrant chromosome, unequal distribution of chromatin and bridge. This genotoxic effect of MnCl2 was associated with DNA-MnCl2 interaction, and this interaction was also confirmed by bathochromic and hypochromic shifts in spectral analysis. Anatomical damages such as epidermis cell damage, flattened cell nucleus, cortex cell damage and cortex cell wall thickening were observed after MnCl2 treatment. As a result, it has been determined that excessive doses of the trace element Mn cause physiological, cytogenetic, biochemical and anatomical toxicity and A. cepa test material is a reliable bio-indicator in determining this toxicity.

Cyto-genotoxicity evaluation of pyroligneous acid using Allium cepa assay.

Pyroligneous acid (PA) is a highly oxygenated organic condensate obtained by cooling the gases generated from the pyrolysis process. PA has been used in agriculture for several years with multiple beneficial effects, including plant health and yields, pest resilience, and seed germination. It is generally applied to agricultural soils in the dilution of 1:1000 to 1:100, corresponding to 0.1-1% PA concentration. In this study, the cyto-genotoxic potential of PA to Allium cepa meristematic root-tips (where all cells undergo repeated division and form primary root tissues) was examined. Exposure to PA concentrations of 0.1% and above showed a reduction in the mitotic index percentage, and at 5%, a complete arrest in the cell division was recorded. However, chromosomal aberrations at 0.5, 1, and 3% PA were reversible types such as bridges, vagrants, laggards, and multipolar anaphase, with a maximum of only 5.8% chromosomal aberration observed at 3% PA. Comet assay (single-cell gel electrophoresis) for genotoxicity assessment determined using PA exposed A. cepa root tips showed that it was not genotoxic. The absence of cyto-genotoxicity in A. cepa, even at concentrations far above what would be typically encountered in agricultural applications, strongly suggests that PA is unlikely to cause adverse effects on crops and ultimately on the biota and human health.

Acute multiple toxic effects of Trifloxystrobin fungicide on Allium cepa L.

Trifloxystrobin (TFS) is a strobilurin-type fungicide that should be investigated due to its risks to non-targeted organisms. The goal of this study was to assess the susceptibility of Allium cepa L. to TFS in a multi-pronged approach. For 72 h, 0.2 g/L, 0.4 g/L and 0.8 g/L doses of TFS were administered to A. cepa bulbs and the control group was treated with tap water. The toxic effects of TFS were tested, considering physiological, cytogenetic, biochemical and anatomical analyses. TFS delayed growth by reducing the rooting ratio, root elongation and weight increase. Following TFS treatments, mitotic index (MI) scores decreased, while the formation of micronucleus (MN) and chromosomal aberrations (CAs) ascended. CAs types induced by TFS were listed according to their frequency as fragment, vagrant chromosome, sticky chromosome, uneven distribution of chromatin, bridge, nucleus with vacuoles, reverse polarization and irregular mitosis. TFS provoked an increment in superoxide dismutase (SOD) and catalase (CAT) enzyme activities as well as an accumulation of malondialdehyde (MDA). Meristematic cells of A. cepa roots treated with TFS had various anatomical damages, including damaged epidermis, flattened cell nucleus, damaged cortex and thickness in the cortex cell wall. All damages arising from TFS treatments exhibited dose-dependency. The findings of the present study revealed the serious toxicity of TFS in a non-targeted plant. It should not be neglected to evaluate the potential hazards of TFS with different toxicity tests.

Cytotoxic and genotoxic evaluation of bisphenol S on onion root tips by Allium cepa and comet tests.

Bisphenol S (BPS) is an analog of bisphenol A, which is used as substitute of BPA in many products like airport luggage tags, baby bottles, plastics, and epoxy resins etc. Bisphenol S can cause toxic effects in different organisms, i.e., mice, rat, zebrafish, and C.elegans, etc. Bisphenol S is also known as "endocrine disruptor" due to its ability to mimic the endocrine receptors. So, the aim of this study was to evaluate the cytotoxic and genotoxic effects of bisphenol S on meristematic cells present in onion root tips through Allium cepa (A.cepa) and comet tests. Root growth inhibition was evaluated by root growth inhibition assay. Mitotic index (MI) and chromosomal aberrations (CAs) were assessed by A.cepa assay. DNA damage was evaluated by comet assay. Root growth of A.cepa was inhibited due to bisphenol S. LC50 value calculated by root growth inhibition assay for bisphenol S was (2.6±0.63, 50 µg/ml). Mitotic index was reduced, and chromosomal aberrations were observed, i.e., stickiness, polyploidy, and disturbed ana-telophase in anaphase and telophase stages of mitosis. In case of comet assay, DNA damage was increased in statistically significant manner (p ≤ 0.05). It was concluded that bisphenol S constitutes cytotoxic and genotoxic effects on A. cepa root meristematic cells. Moreover, it is suggested to explore more toxicity studies of bisphenol S at molecular level.

Modulation of atrazine-induced chromosomal aberrations and cyclin-dependent kinases by aqueous extract of Roylea cinerea (D.Don) Baillon leaves in Allium cepa.

Roylea cinerea (D.Don) Baillon an indigenous medicinal plant of Lamiaceae family used for the treatment of several diseases. In the present study, its aqueous (leaves) extract was tested for genoprotective action against atrazine-induced chromosomal aberrations in the root tip cells of Allium cepa. Atrazine is a herbicide of triazine class commonly used to inhibit the growth of broad leaf and grassy weeds. In order to find the concentration of atrazine that exhibits maximum toxicity, its different concentrations (1, 5 and 10 µg/mL) were tested. It was observed that 10 µg/mL concentration was more toxic as it reduced the mitotic index and also increased the chromosomal aberrations. Among all the tested concentrations of aqueous (leaves) extracts (0.25. 0.5, 1.0, 1.5 and 3.0 µg/mL), the3.0 µg/mL concentration in both modes of experiments i.e. pre and post showed a significant reduction in chromosomal aberrations induced by atrazine. To understand the mechanism of protection by plant extract on atrazine-induced chromosomal abnormalities the RT-qPCR studies were conducted to observe the expression of marker genes Cyclin-dependent kinases (CDKs) (CDKA:1, CDKB2:1 and CDKD1:1. For this, the RNA was extracted from root tips treated with extract along with atrazine by TRIzol®. It was observed that aqueous extract of Roylea cinerea (D.Don) Baillon leaves upregulated the CDKs gene expression in both the modes i.e. pre and post treatments. A critical analysis of results indicated that aqueous extract ameliorated the chromosomal aberrations caused by atrazine which may be be due to the increased expression level of CDKs genes.

Determination of genotoxic damages of picloram and dicamba with comet assay in Allium cepa rooted in tissue culture and distilled water.

BACKGROUND: Many genotoxicity tests allow us to understand the mechanism of damages on genetic material occurring in living organisms against various physical and chemical agents. One of them is the Comet test. The current study aimed to evaluate genotoxic caused by picloram and dicamba to root meristems of Allium cepa utilizing comet assay. METHODS: Two different protocols were used for rooting and auxin/pesticide application. (i) A. cepa bulbs were rooted in MS medium and then treated with Murashige and Skoog (MS) medium (control) and 0.67, 1.34, 2.01, 2.68, 3.35, 4.02, and 8.04 mg/L of picloram and dicamba using aseptic tissue culture techniques. (ii) A. cepa bulbs were then rooted in bidistilled water and treated with 0 (control), 0.67, 1.34, 2.01, 2.68, 3.35, 4.02, and 8.04 mg/L of picloram and dicamba in distilled water. The A. cepa root tip cells in both treatment groups were examined using comet test to find the possible DNA damaging effects of picloram and dicamba. RESULTS: The results obtained at all the concentrations were statistically compared with their control groups. Almost at all the concentrations of Picloram and dicamba increased comet tail intensity (%) and tail moment in roots treated in MS medium. Two highest concentrations revealed toxic effect. On the other hand, DNA damaging effect of both auxins was only noted on the highest (> 4.02 mg/L) in roots treated in distilled water. CONCLUSIONS: This study approve and confirm genotoxic effects of how growth regulators on plants. These findings give an evidence of DNA damage in A. cepa. Therefore, both picloram and dicamba should only be used in appropriate and recommended concentrations in agriculture to conserve ecosystem and to pose minimum threat to life.

Sustainable agronomic response of carbon quantum dots on Allium sativum: Translocation, physiological responses and alternations in chromosomal aberrations.

The revolutionary growth in the usage of carbon quantum dots (CQDs) in different areas have ultimately directed their discharge in the environment and further augmented the exposure of agricultural crops to these released particles. Therefore, the aim of current study is to evaluate the uptake, translocation and phytotoxicity of blue emissive CQDs on Allium sativum plant. The genotoxicity and cytotoxicity assessment of CQDs towards Allium sativum roots was estimated as function of three different concentrations. Considering the role of CQDs in promoting seed germination at 50 ppm concentration, a greenhouse experiment was performed to evaluate their effect on plant growth. Systematic investigations have shown the translocation of CQDs and their physiological response in terms of increased shoot length wherein P-CQDs exhibited more accumulation into Allium sativum parts. Our investigations unfold the opportunity to utilize Aegle marmelos fruit derived CQDs as a growth regulator in variety of other food plants.

Cytogenotoxicity assessment in Allium cepa roots exposed to methyl orange treated with Oedogonium subplagiostomum AP1.

The present study is an attempt to assess the cytogenotoxic effect of untreated and methyl orange treated with Oedogonium subplagiostomum AP1 on Allium cepa roots. On the fifth day, root growth, root length, mitotic index, mitotic inhibition/depression, and chromosomal abnormalities were measured in root cells of Allium cepa subjected to untreated and treated methyl orange dye solutions. Roots exposed to treated dye solution exhibited maximum root growth, root length and mitotic index, whereas roots exposed to untreated dye solution had the most mitotic inhibition and chromosomal abnormalities. Allium cepa exposed to untreated dye solution revealed chromosomal aberrations such as disoriented and abnormal chromosome grouping, vagrant and laggard chromosomes, chromosomal loss, sticky chain and disturbed metaphase, pulverised and disturbed anaphase, chromosomal displacement in anaphase, abnormal telophase, and chromosomal bridge at telophase, spindle disturbances and binucleate cells. The comet test was used to quantify DNA damage in the root cells of A. cepa subjected to untreated and treated methyl orange solutions in terms of tail DNA (percent) and tail length. The results concluded that A. cepa exposed to methyl orange induced DNA damage whereas meager damage was noted in the treated dye solution. As a result, the research can be used as a biomarker to detect the genotoxic effects of textile dyes on biota.

What can the Allium cepa test say about pesticide safety? A review.

The increasing use of pesticides has caused global concerns about the toxic effects and adverse consequences of pesticides on humans and the environment. Among the ways to understand the impact of pesticides, the Allium cepa bioassay stands out. This test is suitable to evaluate different toxic, cytotoxic, genotoxic, and mutagenic outcomes. In this context, the present review aimed to summarize the history of using the A. cepa bioassay to investigate pesticide damages. Data on the experimental conditions were also discussed. The reviewed studies showed the toxicity profile of 113 active ingredients primarily tested in the laboratory, using water for exposure. The most used biomarkers were the mitotic index, chromosomal aberrations, and nuclear abnormalities. All active ingredients caused some toxicity levels in A. cepa, showing the efficiency and sensibility of this bioindicator and the adverse effect of pesticides on humans and the environment. Furthermore, it was evident that pesticides have great potential to damage the mitotic spindle and DNA because almost all active ingredients tested induced chromosomal aberrations and nuclear abnormalities. The current review showed that the A. cepa bioassay is an effective and appropriate model to evaluate pesticide toxicity, and it might indicate research gaps and recommendations for further studies.

Genotoxic and cytotoxic effects of pethoxamid herbicide on Allium cepa cells and its molecular docking studies to unravel genotoxicity mechanism.

Pethoxamid is chloroacetamide herbicide. Pethoxamid is commonly used to kill different weeds in various crops. Pethoxamid can leach in the water and soil and can cause toxic effects to other non-target species. Current study is therefore aimed to perform the investigation of the cytotoxic and genotoxic effects of pethoxamid on Allium cepa cells.The root growth, mitotic index (MI), chromosomal aberrations (CAs), and DNA damage were assessed through root growth inhibition, A. cepa ana-telophase, and alkaline comet assays, respectively. Furthermore, molecular docking was performed to evaluate binding affinity of pethoxamid on DNA and very-long-chain fatty acid (VLCFA) synthases. In root growth inhibition test, onion root length was statistically significantly decreased in a concentration dependent manner. Concentration- and time-dependent decreases in MI were observed, whereas increase in CAs such as disturbed ana-telophase, chromosome laggards, stickiness, anaphase bridges, and DNA damage was caused by the pethoxamid on A. cepa root cells. Molecular docking revealed that pethoxamid binds selectively to GC-rich regions in the minor groove of the DNA structure and showed remarkable binding affinity against all synthases taking part in the sequential biosynthesis of VLCFAs. It was concluded that the pethoxamid-induced genotoxicity and cytotoxicity may be through multiple binding ability of this herbicide with DNA and VLCFA synthases.

Cytotoxic and genotoxic effects induced by associated commercial glyphosate and 2,4-D formulations using the Allium cepa bioassay.

Studies assessing the toxicity of glyphosate and 2,4-dichlorophenoxyacetic acid mixture are scarce. The aim of this study was to evaluate the cytotoxicity and genotoxicity of the mixture of these herbicides using Allium cepa. Roots were exposed to glyphosate (1.56 and 11.66 mg mL-1), 2,4-D (0.28 and 17.5 mg mL-1) and mixture for 24 h, based on the average concentration applied in the field and the acute reference dose (ARfD) established in Brazil. Both isolated and associated herbicides induced a significative decrease in mitotic index (MI) (P < 0.0001) in all tested concentrations. Regarding the genotoxicity results, 2,4-D and the mixture showed, at concentrations applied in the field, a significative increase of chromosomal anomalies (CA) index compared to control (P < 0.0001) and glyphosate (P = 0.024 and P = 0.0002, respectively). All tested groups from the ARfD showed a significative difference compared to the control group (P < 0.0001), as well as glyphosate and 2,4-D isolated compared to the mixture (P = 0.0005 and P < 0.0001, respectively). The most observed CA were apoptotic bodies, giant cells, and nuclear erosions. We emphasize the need for further studies assessing the toxicity of these herbicides' mixture due to the distinct effects caused in different organisms.

Mutagenic and teratogenic toxicity evaluation of Forsythia suspensa leaves aqueous extract.

Forsythia suspensa leaves (FSL), rich in phillyrin, forsythiaside A, phillygenin, rutin, and other compounds, is a known traditional Chinese medicine (TCM). It has been effective in heat retreat and detoxification. In this study, we performed the mutagenic and teratogenic toxicity evaluation of FSL aqueous extract (FSLAE) using the bacterial reverse mutation assay (Ames test), mouse bone marrow micronucleus assay, spermatocyte chromosomal aberration assay in mice. Kunming mice and SD rats were used were for the mutagenic and the teratogenic studies, respectively. We found that FSLAE was not mutagenic and did not induce unfavorable chromosomal events. Additionally, the Ames test revealed FSLAE was not genotoxic and showed no mutagenic activity in histidine dependent strains of Salmonella typhimurium at concentrations up to 5000 µg/plate. Likewise, in vivo test revealed no induced micronucleus of mouse bone marrow or chromosome aberration in spermatocytes up to the dose of 10.00 g/kg BW. For the teratogenic evaluations, pregnant rats were treated with 1.04, 2.08, and 4.17 g/kg FSL, and fetuses were examined on the 6-15 day of pregnancy. We observed no maternal toxicity and embryotoxicity related to the treatment. Based on these in vitro and in vivo studies, we concluded the genotoxic and teratogenic safety of FSL.

A toxicological evaluation of lithium orotate.

Lithium orotate, the salt of lithium and orotic acid, has been marketed for decades as a supplemental source of lithium with few recorded adverse events. Nonetheless, there have been some concerns in the scientific literature regarding orotic acid, and pharmaceutical lithium salts are known to have a narrow therapeutic window, albeit, at lithium equivalent therapeutic doses 5.5-67 times greater than typically recommended for supplemental lithium orotate. To our knowledge, the potential toxicity of lithium orotate has not been investigated in preclinical studies; thus, we conducted a battery of genetic toxicity tests and an oral repeated-dose toxicity test in order to further explore its safety. Lithium orotate was not mutagenic or clastogenic in bacterial reverse mutation and in vitro mammalian chromosomal aberration tests, respectively, and did not exhibit in vivo genotoxicity in a micronucleus test in mice. In a 28-day, repeated-dose oral toxicity study, rats were administered 0, 100, 200, or 400 mg/kg body weight/day of lithium orotate by gavage. No toxicity or target organs were identified; therefore, a no observed adverse effect level was determined as 400 mg/kg body weight/day. These results are supportive of the lack of a postmarket safety signal from several decades of human consumption.