Allium Cepa Root Research Articles

Cytotoxic and genotoxic effects of clopyralid herbicide on Allium cepa roots.

Clopyralid is one of the synthetic pyridine-carboxylate auxin herbicides and used to control perennial and annual broadleaf weeds in wheat, sugar beets, canola, etc. In this study, dose-dependent cytotoxicity and genotoxicity of clopyralid at different concentrations (25, 50, and 100 μg/mL) have been evaluated on the Allium cepa roots. The evaluation has been performed at macroscopic (root growth) and microscopic levels [mitotic index (MI), chromosome aberrations (CAs) in ana-telophase cells, and DNA damage] using root growth inhibition, Allium ana-telophase, and comet tests. The percentage of root growth inhibition and concentration of reducing root growth by 50% (EC50) of clopyralid were determined compared with the negative control by using various concentrations of clopyralid (6.25-1000 μg/L). The 96 h EC50 of clopyralid was recorded as 50 μg/L. The gradual decrease in root growth and the MI reveals the cytotoxic effects of clopyralid. All the tested concentrations of clopyralid induced total CAs (polyploidy, stickiness, anaphase bridges, chromosome laggards, and disturbed ana-telophase) and DNA damage dose and time dependently. These results confirm the cytotoxic and genotoxic effects of clopyralid on non-target organism.

Cyto-genotoxicity, antibacterial, and antibiofilm properties of green synthesized silver nanoparticles using Penicillium toxicarium.

The fungi are becoming the distinguished organisms utilized in the biological synthesis of metallic nanoparticles because of their metal bioaccumulation ability. Addressed herein, the extracellular synthesis of silver nanoparticles (AgNPs) was carried out by using the cell-free filtrate of Penicillium toxicarium KJ173540.1. P. toxicarium was locally isolated and identified using both classical and molecular methods according to ribosomal internal transcribed spacer area of 18S rDNA. The optimum conditions for the AgNPs synthesis were found as 0.25 mM AgNO3 concentrations with pH 12 values at 45°C after 64 hr incubation in dark. Biosynthesized AgNPs were characterized via microscopic and spectroscopic techniques such as transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray analysis, Fourier transform infrared spectrophotometer, and ultraviolet-visible spectroscopy. Zetasizer measurements presented that the high negative potential value (-18.1 mV) and PDI (0.495) supported the excellent colloidal nature of AgNPs with long-range stability and high dispersity. AgNPs exhibited cyto-genotoxicity in Allium cepa root meristem cells by decreasing mitotic index and increasing chromosome aberrations in a dose-dependent manner. Then, 100 and 50% concentration of biosynthesized AgNPs showed antibacterial activity on Staphylococcus aureus and Bacillus subtilis. A decreasing biofilm formation of Pseudomonas aeruginosa 80.69, 48.32, and 28.41% was also observed at 100, 50, and 25% of mycosynthesized AgNP, respectively.

Cytotoxic and genotoxic evaluation of copper oxychloride through Allium test and molecular docking studies.

Copper oxychloride gained great importance due to its broad-spectrum antifungal action to combat various fungal diseases of plants. However, excess quantity of cupric fungicides on plants causes enzymatic changes and toxic effects. Thus, the current study was aimed to investigate the cytotoxicity and genotoxicity of copper oxychloride on Allium cepa root 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. Furthermore, molecular docking was performed to evaluate binding affinities of two copper oxychloride polymorphs (atacamite and paratacamite) on DNA. In root growth inhibition test, onion root length was statistically significantly decreased by changing the copper oxychloride concentration from lower (2.64±0.11 cm) to higher (0.92±0.12 cm). Concentration- and time-dependent decrease in MI was observed whereas increase in CAs such as disturbed ana-telophase, chromosome laggards, stickiness, anaphase bridges, and DNA damage were caused by the copper oxychloride on A. cepa root cells. Molecular docking results revealed that the two main polymorphs of copper oxychloride (atacamite and paratacamite) bind selectively to G and C nucleotides on the B-DNA structure. It is concluded that the atacamite- and paratacamite-induced DNA damage may be through minor groove recognition and intercalation. Findings of the current study revealed the cytotoxic and genotoxic effects of copper oxychloride on A. cepa root cells. However, further studies should be carried out at the molecular level to reveal the cyto-genotoxic mechanism of action of copper oxychloride in detail.

Growth inhibitory properties and antimicrobial evaluation of Aloe schweinfurthii (Baker) leaf rind extract

Cancer and infectious diseases combined are leading cause of death and public health concern. In developing countries, about 80% of the populace depends on medicinal plants for their general health care needs including treatment of infectious diseases and cancer. Aloe schweinfurthii (Aloaceae) is a small medicinal herb that is commonly used for the treatment of cancerous and infectious diseases in South-West Nigeria. The focus of this study was to evaluate the growth inhibitory and antimicrobial activities of the herb. The rind of the herb was collected, air dried, pulverized and extracted into distilled methanol by cold maceration. The dried extract obtained was subjected to growth inhibitory and antimicrobial assays. The extract displayed concentration dependent growth inhibitory activity with IC50 of 484.7±2.16 and 1188±2.32µg/mL compared to cyclophosphamide with IC50 of 174.3±0.19 and 834.5±0.84 µg/mL in Sorghum bicolor radical and Allium cepa root growth inhibitory assays, respectively. The extract displayed concentration dependent antibacterial and antifungal effects with the highest activity against C. freundi (18 mm zone of inhibition) at 50 mg/mL. The extract of Aloe schweinfurthii leaf rind displayed marked growth inhibitory and antimicrobial bioactivities. The extract maybe considered as a viable candidate for discovery of chemotherapeutic agent (s).
 Keywords: Growth inhibition, Antimicrobial, Aloe schweinfurthii, Chemotherapeutic Agent

Effect of Phaulopsis falcisepala (Acanthaceae) Leaves and Stems on Mitotic Arrest and Induction of Chromosomal Changes in Meristematic Cells of Allium Cepa

Phaulopsis falcisepala is an herb found in the forest zone of West Africa. It is applied ethnomedicinally for treating wounds and cancer. This study investigated the chemical constituents, cytotoxicity, and antimitotic activity of P. falcisepala leaves and stems. Chemical constituents were evaluated using phytochemical methods. Cytotoxicity was investigated using brine shrimp lethality and Allium cepa root growth inhibition assays. Antimitotic activity and induction of chromosomal aberrations were assessed by cytological examination of treated A. cepa meristematic cells. Chemical investigation revealed the presence of diverse bioactive chemical groups, including alkaloids, terpenoids, tannins, flavonoids and saponins in various extracts of the leaves and stems of P. falcisepala. Aqueous and methanol extracts contained copious amounts of the phytochemicals while ethyl acetate and n-hexane extracts contained moderate to trace amounts. The extracts demonstrated toxicity against brine shrimps, with LC50 values in the range 13.1–52.2 µg/mL. The extracts significantly inhibited A. cepa root growth, with IC50 values in the range 63.91–87.4 µg/mL and 45.34– 81.15µg/mL for 24 and 48 h treatments. The extracts (IC50 values in the range 46.2–94.23 µg/mL and 30.79–75.81 µg/mL for 24 and 48 h treatments) produced significant antimitotic effect comparable to or greater than that of methotrexate (IC50 value >125 µg/mL). Cytological examinations revealed that the extracts induced mitotic arrest and chromosomal changes. This study reports for the first time the phytoconstituents and cytotoxic activity of P. falcisepala supporting its ethnomedicinal use and could serve as the basis for further pharmacological studies and isolation of bioactive principles.

Assessment of Genotoxicity and Cytotoxicity of Leached Chemicals from HDPE Plastic Commonly Used by Ambulant Vendors

Plasticizers and additives in plastics like polyethylene terephthalate (PET) bottles have been found to leach – especially when exposed to certain stresses, including temperature. Frequent exposure to these chemicals is associated with a higher risk of developing developmental and reproductive disorders and cancer. In this study, water at varying temperatures (28, 65, 75, and 85 °C) was contained in high-density polyethylene (HDPE) plastic “labo,” a food packaging material common in the Philippines. Gas chromatography–mass spectrometry (GC-MS) analysis showed that the leached chemicals were derivatives of plastic additives and compounds or degradation compounds of these chemicals. Notable leachates include dimethyl sulfoxide, isosorbide, and cyclohexene derivatives. Different compounds leached at different temperatures. The Allium cepa test revealed chromosomal aberrations such as anaphase with bridge, sticky chromosomes, and chromosomal breaks. These signify that the compounds may be genotoxic to Allium cepa root tip cells. The Allium cepa test, brine shrimp lethality assay, and MTT assay on MCF-7 cells were also conducted as preliminary cytotoxicity tests. Results showed an increase in mitotic activity for Allium cepa root tip cells and induced proliferation of MCF-7 cells. Moreover, the mortality rates of Artemia salina were low after 24 h of exposure. These findings provide additional information regarding the leaching from plastic labo – the identity of leached chemicals and the effects of exposure on various cell lines and organisms. These findings may be used as a basis for existing policies regarding the use of plastic as food packaging material.

Clastogenic, anti-clastogenic profile and safety assessment of Camel urine towards the development of new drug target

Camel Urine (CU) is composed of components that have antitumor properties and other therapeutic benefits. Regardless of short-term preliminary CU genotoxicity is reported, comprehensive genotoxic studies are limited. In this study, sensitive in vitro and in vivo genotoxic bioassays such as mitotic index (MI), chromosomal aberrations (CA), micronucleated polychromatic erythrocytes (MPE), and analysis of primary spermatocytes were employed. The adventitious roots of Allium cepa L. and mice (Mus musculus), as an experimental mammalian system, were employed to assess the MI and CA of CU induced by sodium nitrate and cyclophosphamide respectively. In contrast, other clastogenic assays were studied in mice (Mus musculus). Twenty-eight days of four repeated doses (2.5, 5, 25, and 50 mL/kg BW) of CU were tested and compared with three doses (10, 25, and 50 mg/kg BW) cyclophosphamide as a positive control and deionized water as the negative control. The results proved that cytological examination of CU was cytotoxic since a decrease in mitotic activity (16.8–1.1) was observed, since the significant reduction in cell proliferation in A. cepa L. and also in mice bone marrow cells. On the other hand, CU did not induce a clastogenic effect since no significant stickiness, fragment, multinucleoli were observed compared to the control group. Additionally, the data showed that CU decreased the CA when mice had received cyclophosphamide (25 mg BW) followed by CU doses. CU was found to be cytotoxic but no clastogenic effect. Furthermore, it possesses anticlastogenic properties. The observed results suggest that CU in whole or the metabolites present in CU could be a potent drug target. Further research is warranted to study the complete metabolites profiling and to study the molecular mechanisms.

Potentially toxic elements in river water and associated health risks in Ropar Wetland, India and its vicinity

In the present study, quality of surface water from five different locations on the banks of river Sutlej in Ropar wetland was determined by estimation of physico-chemical parameters; water quality indices; contents of arsenic, cadmium, cobalt, chromium, copper, iron, manganese, lead and zinc; determination of genotoxic potential of water samples using Allium cepa root chromosomal aberration assay and plasmid pBR322 DNA nicking assay; and assessment of associated possible human health risks for adults and children. River water was slightly alkaline, moderate to very hard, non-saline, genotoxic and unsuitable for both drinking and irrigation. Among 20 surface water samples analysed, contents of Cd, Cr, Cu, Fe, Mn and Pb in 11, 7, 3, 15, 14 and 13 samples exceeded the safe limits (mg/L) of 0.003, 0.05, 0.05, 0.30, 0.10 and 0.01, respectively. Ingestion of surface posed higher health risk than dermal contact, where Co was major contributor to mean hazard index (3.26–10.72 for adults and 4.22–13.87 for children). Hazard index for dermal contact in both age groups was < 1.00. Cr was found to be primarily responsible for high total cancer risk posed by both routes of exposure, i.e. ingestion (6.83E−04 to 2.03E−03 for adults and 7.58E−05 to 2.25E−04 for children) and dermal contact (5.15E−05 to 2.02E−04 for adults and 6.23E−06 to 2.44E−05 for children). Prolonged exposure to contaminated surface water may elevate the human health risk in the study area; therefore, pre-treatment of river water is necessary before its utilization by human population of the study area.

Effect of Engineered Nickel Oxide Nanoparticle on Reactive Oxygen Species-Nitric Oxide Interplay in the Roots of Allium cepa L.

Scientists anxiously follow instances of heavy metals augmenting in the environment and undergoing bioaccumulation and trace their biomagnification across food webs, wary of their potent toxicity on biological entities. Engineered nanoparticles supplement natural pools of respective heavy metals and can mimic their effects, exerting toxicity at higher concentrations. Thus, a thorough understanding of the underlying mechanism of this precarious interaction is mandatory. Most urban and industrial environments contain considerable quantities of nickel oxide nanoparticles. These in excess can cause considerable damage to plant metabolism through a significant increase in cellular reactive oxygen species and perturbation of its cross-talk with the reactive nitrogen species. In the present work, the authors have demonstrated how the intrusion of nickel oxide nanoparticles (NiO-NP) affected the exposed roots of Allium cepa: starting with disruption of cell membranes, before being interiorized within cell organelles, effectively disrupting cellular homeostasis and survival. A major shift in the reactive oxygen species (ROS) and nitric oxide (NO) equanimity was also observed, unleashing major altercations in several crucial biochemical profiles. Altered antioxidant contents and upregulation of stress-responsive genes, namely, Catalase, Ascorbate peroxidase, Superoxide dismutase, and Rubisco activase, showing on average 50–250% rise across NiO-NP concentrations tested, also entailed increased cellular hydrogen peroxide contents, with tandem rise in cellular NO. Increased NO content was evinced from altered concentrations of nitric oxide synthase and nitrate reductase, along with NADPH oxidase, when compared with the negative control. Though initially showing a dose-dependent concomitant rise, a significant decrease of NO was observed at higher concentrations of NiO-NP, while cellular ROS continued to increase. Modified K/Na ratios, with increased proline concentrations and GABA contents, all hallmarks of cellular stress, correlated with ROS–NO perturbations. Detailed studies showed that NiO-NP concentration had a significant role in inducing toxicity, perturbing the fine balance of ROS–NO, which turned lethal for the cell at higher dosages of the ENP precipitating in the accumulation of stress markers and an inevitable shutdown of cellular mechanisms.

Effect of Setophoma terrestris, Sclerotium cepivorum, and Trichoderma spp. on in vitro onion (Allium cepa) root tissues and the final yield at the field

Trichoderma is a rhizosphere fungus widely used in agriculture due to the variety of mechanisms of biological control. It can establish a direct relationship with the plant root cells, modifying the morphology and physiological processes, conferring a better defensive capacity against the attack of pathogens in the soil. This research aimed to study the interaction of T. asperellum, T. harzianum, T. virens, Setophoma terrestris and Sclerotium cepivorum on onion roots (Allium cepa), both in vitro and in field trials, to evaluate the histological modifications and the effect on in vitro growth promotion, and to test the effect of Trichoderma in the field, over the incidence of these pathogens and the crops harvest. In vitro plant promotion assay was made using T. asperellum, T. harzianum, and T. virens to test their effect on the development of onion seedlings from disinfected seeds. Roots of these plants were subjected to histological analysis using Transmission Electronic Microscopy (TEM) to examine changes in cell structure. This analysis also included the pathogens S. cepivorum and S. terrestris, the major soilborne pathogens of onion worldwide. To verify the effect of the Trichoderma species used in the study, a field experiments were performed where the fresh and dry weight of onion bulbs and the incidence of pathogens were measured. Histological modifications were observed in the root cells in the different treatments and were related to the effects caused for Trichoderma. It was shown that although T. asperellum did not stimulate in vitro root growth it can have an important effect in the field by reducing the incidence of S. cepivorum and S. terrestris while improving the onion’s harvest. On the contrary, species that have a root promoting effect do not necessarily improved yield. Besides, rather than this study, there are no other histological studies published in the onion- S. terrestris pathosystem.

A Comparative Analysis of Bark and Leaf Essential Oil and their Chemical Composition, Antioxidant, Anti-inflammatory, Antimicrobial Activities and Genotoxicity of North East Indian Cinnamomum zeylanicum Blume

Background: Cinnamomum zeylanicum Blume ( Lauraceae) bark and leaf essential oil possesses eugenol as the major component. Both the essential oils have the potential antioxidant, anti- inflammatory, antimicrobial and negligible genotoxicity. Objective: A comparative chemical composition and biological evaluation of Cinnamomum zeylanicum Blume, bark and leaf essential oils, originated from North-East India has been investigated in the present study. Methods: Gas chromatography/mass spectroscopy analysis was used to investigate the chemical composition of the essential oil samples. DPPH free radical scavenging activity, and reducing power assay were used for antioxidant activity evaluation. Similarly, egg albumin denaturation assay, protease inhibitory activities were used for anti-inflammatory activity, while genotoxicity was evaluated by using Allium cepa assay and antimicrobial activities using disc diffusion and minimum inhibitory concentration assay. Results: The GC/MS results showed that eugenol is the major component of C. zeylanicum bark (84.48%) and leaf (48.78 %) essential oil. Significant antioxidant activity was observed for both essential oils in the DPPH free radical scavenging assay (IC50= 103.2 μg/mL, bark; IC50= 234.7 μg/mL, leaf), and reducing power assay (absorbance of 1.802 nm, 0.907 nm in 48 μg/mL for bark and leaf essential oil respectively). In-vitro anti-inflammatory activity revealed strong potential of leaf essential oil (protein denaturation assay, IC50= 0.05279 μg/mL; protease inhibitory activity IC50= 3.607 μg/mL) in comparison to bark essential oil (protein denaturation assay IC50= 0.1491, protease inhibitory activity IC50= 61.06). Allium cepa root growth test, mitotic index, and chromosomal aberration test were performed to investigate the genotoxicity of C. zeylanicum bark and leaf essential oil, which resulted in no toxic nature of both the essential oils. Antimicrobial activity against eight bacterial and fungal strains revealed good antimicrobial properties with the MIC value of Staphylococcus aureus at 5 μL/mL (bark), Aspergillus niger at 2.5 μL/mL (bark); Bacillus cereus at 5 μL/mL (leaf) and Aspergillus niger at 2.5 μL/mL (leaf). Conclusion: Collectively, these findings indicated the strong biological potential of both essential oils, although bark essential possesses better biological activities than the leaf essential oil and could be used in the food and beverage industries.

Cytogenetic toxicity from pesticide and trace element mixtures in soils used for conventional and organic crops of Allium cepa L.

Pesticides and trace elements occur in complex mixtures in agroecosystems, affecting soil health and food security. Hence, it is necessary to determine their toxicity in field conditions and to develop monitoring approaches to assess conventional and organic agriculture. The aim of this research was to evaluate the associations between Allium cepa L. cytogenetic biomarkers and the realistic mixture of pesticides and trace elements found in soils of conventional, conversion, and organic crops in an intensive agricultural region in Colombia. Pesticide screening was conducted using GC-MS/MS and LC-MS/MS methods. Arsenic, cadmium, lead, and zinc were analyzed by ICP-MS; chromium, copper, nickel, and selenium by ICP-OES; and mercury by a direct analyzer. The meristematic cells in roots of Allium cepa L. were analyzed through microscopic observations to quantify cytogenetic effects. In conventional crops, 26 pesticides were detected in the soil samples, and those were below the limit of quantification in organic crops. The mean levels of As, Cd, Cr, Ni, Pb, and Se were also greater in soils of conventional crops compared to the organics. In addition, the biomarkers of cytotoxicity and genotoxicity appeared augmented in conventional samples, and those were correlated with pesticide and trace element concentrations, pollution indices, and hazard quotients. Subsequently, a discriminant function based on the mitotic index, chromosomal aberrations, and nuclear abnormalities was suitable to classify the samples by crop type. These results demonstrate the sensitivity of Allium cepa L. to the toxicity of complex mixtures in field crops and its potential as an in-situ approach for soil health monitoring in organic and conventional crop systems.

Chemical composition and phytotoxicity of essential oil from invasive plant, Ambrosia artemisiifolia L.

Essential oils have been evaluated as appropriate phytotoxins with mechanisms of action that are different from those of synthetic herbicides applied in weed management activities, but little is known about the effect of Ambrosia artemisiifolia essential oil (EO) on weeds. Here, the chemical composition of A. artemisiifolia EO was analyzed using a Gas Chromatography-Mass Spectrometry system. and the phytotoxic activities of the EO against monocot (Poa annua, Setaria viridis) and dicot (Amaranthus retroflexus, Medicago sativa) species are evaluated under laboratory and green-house conditions for the first time. The EO was rich in sesquiterpenes (62.51%), with germacrene D (32.92%), β-pinene (15.14%), limonene (9.90%), and caryophyllene (4.49%) being the major compounds based on Gas Chromatography-Mass Spectrometry analysis results. A. artemisiifolia EO inhibited seed germination and seedling development significantly in the tested species even at low concentrations (0.25 mg mL−1). In addition, bioassay results for the activities of superoxide dismutase (SOD) and peroxidase (POD) increased and then decreased with an increase in EO concentration. Unlike the enzymatic activity, root cell viability declined significantly in the tested weeds in all EO treatments. Besides, a foliar spray experiment resulted in visible injury in leaves and a decrease in chlorophyll content and eventually led to wilting of all tested weeds. The EO (0.25–5.00 mg mL−1) altered Allium cepa root tip cells with a decline in mitotic index and an increase in chromosomal aberrations after 24 h treatment. The cytotoxic evaluation confirmed the mitotic inhibitory effect of EO, although the intensity varied under different concentrations. According to the results, A. artemisiifolia EO has the potential applications as a natural herbicide owing to its phytotoxic activity; which also helps to explain their potential involvement in allelopathic interaction of volatile compounds present in the EO that facilitate the invasion success of the exotic species.

Cytotoxic and genotoxic assessment of tungsten oxide nanoparticles in Allium cepa cells by Allium ana-telophase and comet assays.

Tungsten oxide nanoparticles or nanopowder (WO3NPs) is commonly used in various industries and also in biomedical applications such as additives, pigments, and biomedical sensors. Non-judicious excessive use of these nanoparticles (NPs) could be a serious human health concern. Therefore, the current study aimed to explore the cytotoxic and genotoxic assessment of WO3NPs through Allium cepa anaphase-telophase and comet assays. Nanoparticles were characterized through the scanning and transmission electron microscopy (TEM), zetasizer, and energy-dispersive X-ray spectroscopy. The mean size and the average diameter of WO3NPs were determined as 21.57 ± 2.48nm and 349.42 ± 80.65nm using TEM and a Zetasizer measurement system, respectively. Five concentrations (12.5mg/L, 25mg/L, 50mg/L, 75mg/L, and 100mg/L) of WO3NPs were employed on the Allium cepa (A. cepa) roots for 4h. Significant (p≤ 0.05) decrease in mitotic index (MI) was shown by WO3NPs at all concentrations. The increase of chromosomal aberrations (CAs) was also observed in a concentration-dependent manner due to the WO3NPs exposure. There was a significant increase (p≤ 0.05) in DNA damage at all concentrations of WO3NPs on the A. cepa cells. It was concluded that WO3NPs had cytotoxic and genotoxic effects on A. cepa meristematic cells. Moreover, further cytogenetic effects of WO3NPs should be investigated at the molecular level to assess its safety margin.

Assessment of Toxic Effects of Titanium Dioxide and Zinc Oxide Nanoparticles in Allium cepa Roots

Assessment of Toxic Effects of Titanium Dioxide and Zinc Oxide Nanoparticles in Allium cepa Roots

Comparative Account of the Genotoxic and Antimicrobial Effects of Silver Nanoparticles Synthesized from Extract of Pleurotus Ostreatus and Chemically Synthesized Nanoparticles

Recently, metallic nanoparticles have gained attention for its potential as antibacterial agent. However, because of the risk it poses towards environment, biologically synthesised nanoparticles have got the preference. Green synthesis of silver nanoparticles (AgNPs) from edible mushrooms are considered to be cost effective and eco-friendly. In this study, we found that biologically synthesised AgNPs from the water extracts of Pleurotus ostreatus exhibited less cytotoxic effect on mitotic chromosomes of Allium cepa root meristem, when compared to chemically synthesised AgNPs. The synthetic AgNPs possesses high genotoxic effect including spindle disruption, sticky metaphase chromosomes, multipolarity, early and late anaphase etc. Results also prove that these biologically synthesised AgNPs possess better antimicrobial properties than the chemically synthesized one against both the gram-positive (Bacillus, Staphylococcus) and the gram-negative bacteria (Escherichia coli, Klebsiella).

Chromosomal aberrations induced by cassava industrial effluent using Allium Cepa assay

This study assessed the heavy metal compositions and chromosome aberrations induced by cassava industrial effluent using Allium cepa meristem assay. Effluent collected at the point of discharge from the cassava processing factory located at Lokoja, Kogi State Nigeria was analyzed for quantity of Cadmium (Cd), Chromium (Cr), Copper (Cu), Manganese (Mn), Iron (Fe), Nickel Ni, Cobalt (Co) and Lead (Pb) using Atomic Absorption Spectrophotometer method. Onion (Allium cepa) roots were allowed to grow in beakers containing different concentrations of cassava industrial effluent (i.e. 25%, 50%, 75% and 100%) and the control for 24 hours. Harvesting of the tips for chromosome observations was carried out between 8:00 to 9:00am West Africa Time. Data pooled under X400 magnification of the light microscope for mitotic phases and chromosome aberrations were analyzed using Analysis of Variance (ANOVA) while means with significant difference across concentrations were separated using Duncan Multiple Range Test (DMRT). The results revealed that only Cadmium (Cd) and Lead (Pb) concentrations in the effluent were higher than the minimum values recommended by World Health Organization. The effluent also produce binucleate cells, variant chromosomes, C-mitosis, vacuolated cells, tripolar anaphase and anaphase bridge which suggests the mutagenic and cytotoxic activities of the industrial effluent. The decrease in the Mitotic Indices (MI) of effluent-treated root cells compared to the control indicates mito-depressive ability of the effluent at every concentration. Regular monitoring of industries for compliance to treatment of effluent before releasing them into the environment is recommended.

Cytotoxic and Genotoxic Effects of Some Azo Dyes in Allium cepa Root Tip Cells

Azo dyes (AD-1, AD-2) were synthesized from the reaction diazonium salts of the aromatic amines salt with the enaminone derivative. The chemical structure of the synthesized novel azo dye (AD-2) was characterized by elemental analysis and other spectral techniques (FTIR, 1H NMR and 13C NMR). Azo dyes are used frequently in the industry and pose a great danger especially for water resources. In this respect, azo dyes threaten many products indirectly in agricultural applications. In this study, the cytotoxic and genotoxic effects of potential azo dyes (AD-1, AD-2) that can be used in industrial applications were determined using Allium test system in five different concentrations (6.25, 12.5, 25, 50, and 100 µM). As a result of the cytogenetic analyzes, it was determined that both azo dyes significantly reduced the number of divisions of A. cepa cells and caused chromosomal abnormalities in dividing cells. As a result, in this research, it is emphasized that the azo dyes (AD-1, AD-2), which are potentially used in the industry, cause genotoxic and cytotoxic effects in the living structures.

Evaluation of Cyto-genotoxicity of Perfluorooctane Sulfonate (PFOS) to Allium cepa.

Per- and polyfluoroalkyl substances (PFAS) have emerged as contaminants of global concern. Among several PFAS, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are persistent and bioaccumulative compounds. We investigated the cyto-genotoxic potential of PFOS to Allium cepa root meristem cells. The A. cepa root tips were exposed to 6 different concentrations (1-100 mg L-1 ) of PFOS for 48 h. Reduction in mitotic index and chromosomal aberrations was measured as genotoxic endpoints in meristematic root cells. Exposure to PFOS significantly affected cell division by reducing the miotic index at higher concentrations (>10 mg L-1 ). The median effect concentration of PFOS to elicit cytotoxicity based on the mitotic index was 43.2 mg L-1 . Exposure to PFOS significantly increased chromosomal aberrations at concentrations >25 mg L-1 . The common aberrations were micronuclei, vagrant cells, and multipolar anaphase. The alkaline comet assay revealed a genotoxic potential of PFOS with increased tail DNA percentage at concentrations >25 mg L-1 . To our knowledge, this is the first study to report the cyto-genotoxic potential of PFOS in higher plants. Environ Toxicol Chem 2021;40:792-798. © 2020 SETAC.

Phorbol 12-Myristate 13-Acetate Induced Toxicity Study and the Role of Tangeretin in Abrogating HIF-1α-NF-κB Crosstalk In Vitro and In Vivo.

Phorbol 12-myristate 13-acetate (PMA) is a potent tumor promoter and highly inflammatory in nature. Here, we investigated the toxic effects of PMA on different model system. PMA (10 μg) caused chromosomal aberrations on the Allium cepa root tip and induced mitotic dysfunction. Similarly, PMA caused embryonic and larval deformities and a plummeted survivability rate on zebrafish embryo in a dose-dependent manner. Persistently, PMA treatment on immortalized human keratinocyte human keratinocyte (HaCaT) cells caused massive inflammatory rush at 4 h and a drop in cell survivability at 24 h. Concomitantly, we replicated a cutaneous inflammation similar to human psoriasis induced by PMA. Herein, we used tangeretin (TAN), as an antagonist to counteract the inflammatory response. Results from an in vivo experiment indicated that TAN (10 and 30 mg/kg) significantly inhibited PMA stimulated epidermal hyperplasia and intra-epidermal neutrophilic abscesses. In addition, its treatment effectively neutralized PMA induced elevated reactive oxygen species (ROS) generation on in vitro and in vivo systems, promoting antioxidant response. The association of hypoxia-inducible factor 1-alpha (HIF-1α)-nuclear factor kappa-light-chain-enhancer of activated b cells (NF-κB) crosstalk triggered by PMA enhanced PKCα-ERK1/2-NF-κB pathway; its activation was also significantly counteracted after TAN treatment. Conclusively, we demonstrated TAN inhibited the nuclear translocation of HIF-1α and NF-κB p65. Collectively, TAN treatment ameliorated PMA incited malignant inflammatory response by remodeling the cutaneous microenvironment.