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Population responses of Daphnia magna, Chydorus sphaericus and Asellus aquaticus in pesticide contaminated ditches around bulb fields
2014
Ieromina, O. | Peijnenburg, W.J.G.M. | de Snoo, G.R. | Vijver, M.G.
The goal of this study was to investigate the effects of ambient concentrations of pesticides combined with abiotic factors on the key aquatic species Daphnia magna, Chydorus sphaericus and Asellus aquaticus by means of 21 days field exposure experiments. In situ bioassays were deployed in ditches around flower bulb fields during spring and autumn 2011–2012. The results showed that phosphate was the most variable parameter followed by pesticides expressed as toxic units, as the main factors explaining differences between sites. Variation in reproduction and growth of cladoceran D. magna was largely explained by nutrients, whereas dissolved oxygen contributed mostly to variations in reproduction of C. sphaericus. Dissolved organic carbon contributed to variations in growth of the detrivore A. aquaticus. It is concluded that abiotic stressors rather than pesticides contributed significantly to the performance of aquatic invertebrates.
Afficher plus [+] Moins [-]Comparison of lead tolerance in Allium cepa with other plant species
1999
Wierzbicka, M. (Environmental Plant Pollution Laboratory, University of Warsaw, Krakowskie Przedmiescie 26/28, 00-927 Warsaw (Poland))
Prediction of biogas and pressure from rumen fermentation using plant extracts to enhance biodigestibility and mitigate biogases
2019
Faniyi, Tolulope O. | Prates, Ênio R. | Adegbeye, Moyosore J. | Adewumi, Micheal K. | Elghandour, Mona M. M. Y. | Salem, Abdelfattah Z. M. | Ritt, Luciano A. | Zubieta, Angel Sánchez | Stella, Laion | Ticiani, Elvis | Jack, Akaninyene A.
Improving digestibility, fermentation characteristics, and reducing greenhouse biogases to protect the environment without the use of synthetic materials is an important goal of modern-day farming and nutritionist. Plant extracts are capable of solving these. This is due to the digestive enzymes and the bioactive components capable of performing antimicrobial functions inherent in these plants. This study was aimed to investigate the effect of standard maize substrate treated with selected herbs and spices extracts on ruminal environmental biogas production and pressure during fermentation via biogas production technique. Herbs (Azadirachta indica leaves (T1), Moringa oleifera leaves (T2), Ocimum gratissimum leaves (T3) and spices (Allium sativum bulb (T4), Zingiber officinale rhizome (T5)) were harvested, air dried, and milled using standard procedures. Methanolic extracts of the herbs and spices were prepared and used as additives at different concentrations (50, 100, and 150 μL) to the maize substrate for in vitro biogas production. Data were analyzed using regression analysis. There were significant (P < 0.05) differences across all the treatments on the volume and pressure of biogas. The pressure and volume of biogas when compared with the levels tested showed differences (P < 0.05) across all the treatments for the prediction of volume from pressure of biogas. The pressure and volume of gas produced in vitro increased (P < 0.05) and biogases decreased (P < 0.05) by the substrate treated with herbs and spices but for the drum stick leaves which was similar for the levels of concentration tested. This means that the level tested had a pronounced mitigation effect on pressure of biogas and volume of biogas produced. It was concluded that the herb and spice extracts have the potential to improve rumen fermentation and reduce the production of biogases in ruminant diet.
Afficher plus [+] Moins [-]Molecular docking and toxicity assessment of spirodiclofen: protective role of lycopene
2021
Çavuşoğlu, Dilek | Yalçin, Emine | Çavuşoğlu, Kültiğin | Acar, Ali | Yapar, Kürşad
In this study, toxic effects of spirodiclofen and protective role of lycopene against toxic effects were investigated by using physiological, cytogenetic, anatomical, and biochemical parameters. Allium cepa L. bulbs were used as test material. The bulbs were divided into six groups as one control and five application groups. Bulb in the control group was germinated with tap water, and in treatment groups, 20-mg L⁻¹ dose of spirodiclofen 215- and 430-mg L⁻¹ doses of lycopene were applied. Spirodiclofen application caused a decrease in physiological parameters such as germination percentage, root length, and weight increase. Spirodiclofen administration caused a decrease in the percentage of mitotic index (MI) and an increase in DNA fragmentation, micronucleus (MN), and chromosomal aberration (CA) frequency. Spirodiclofen application caused an increase in the level of the oxidant compound malondialdehyde (MDA), changes in the level of antioxidant enzymes, and disruption of the oxidant/antioxidant balance in the cell. Molecular interactions between spirodiclofen and antioxidant enzymes were determined by molecular docking analysis. In addition to physiological, biochemical, and genetic abnormalities, spirodiclofen also caused deformations in the anatomy of the A. cepa root tip meristematic cells. Lycopene treatment showed a protective effect by suppressing the toxic effects of spirodiclofen, causing a significant improvement in the values of selected physiological, cytogenetic, anatomical, and biochemical parameters. As a result, spirodiclofen insecticide caused toxic effects on various parameters in A. cepa, which is a eukaryotic model organism. In order to elucidate the toxicity mechanism, each parameter is associated with each other. Molecular docking method has revealed the effects of spirodiclofen on antioxidant enzymes. Lycopene application together with spirodiclofen resulted in the regression of all toxic effects and improvement in the root tissue. This result shows that lycopene has a strong protective property against spirodiclofen toxicity.
Afficher plus [+] Moins [-]Genotoxicity and Anatomical Root Changes in Allium cepa L. (Amaryllidaceae) Caused by the Effluent of the Processing of Ornamental Rocks
2015
Teixeira, Mairy Bitencourt | Fernandes, Ítalo Antônio | de Castro, Evaristo Mauro | Techio, Vânia Helena
The effluent of the ornamental rock industry is characterized by presenting great concentrations of total solids, high contents of iron, and elevated pH, all responsible for the contamination of the superficial and ground waters, destruction of the soil, the vegetation, and the silting of the rivers. The purpose of this study is to assess the cytotoxic and genotoxic effects and the anatomical changes caused by the effluents arising from the ornamental rock polishing industry in root apex cells of Allium cepa L. (Amaryllidaceae). The samples of the effluent were collected in a polishing industry located in Nova Venécia, State of Espírito Santo, and were analyzed by mass spectrometry and atomic emission. Bulbs of A. cepa were exposed to the effluent at 12.5, 25, 37.5, 50, 75, and 100 % concentrations (residue in raw form) (v/v) for a period of 20 days. For the positive control, metilmethanesulfonate (MMS) at 4 × 10⁻⁴-M concentration was used, and distilled water was used for the negative control. The experiment was assessed taking into consideration the following parameters: mitotic index, frequency of chromosomal and nuclear abnormalities in the root apical meristem, and root anatomy. The mitotic index suffered a decrease proportional to the increase in the concentration of effluent. All the concentrations of the effluent led to chromosomal and nuclear abnormalities being stickiness and nuclear shoots the most frequent. The root apex evidenced changes that reflected on the decrease of the percentage area of the protoderm and the fundamental meristem and the increase in the areas of the cap and quiescent center. The symptoms of toxicity are related to the high frequency of cell in cellular death process observed in the roots exposed to the higher concentrations and to the decrease in the mitotic index of the apical root meristem.
Afficher plus [+] Moins [-]Resveratrol ameliorates the physiological, biochemical, cytogenetic, and anatomical toxicities induced by copper(II) chloride exposure in Allium cepa L
2020
Excessive copper (Cu) exposure ultimately results in toxicosis in all organisms. The protective potential of resveratrol compound against the CuCl₂ toxicity was evaluated in Allium cepa L. root tip cells. For this aim, A. cepa bulbs were divided into six groups and the groups were treated with tap water, 400 mg/L resveratrol, 800 mg/L resveratrol, 20 μM CuCl₂, 400 mg/L resveratrol + 20 μM CuCl₂, and 800 mg/L resveratrol + 20 μM CuCl₂ solutions, respectively for 72 h. The first group irrigated with tap water was accepted as control. All groups were screened for the germination percentage, root elongation, total bulb weight gain, micronucleus (MN) frequency, mitotic index (MI), chromosomal aberrations, and anatomical changes. Furthermore, superoxide dismutase (SOD) and catalase (CAT) activities as well as malondialdehyde (MDA) level as an indicator of lipid peroxidation were investigated. It was found that CuCl₂ exposure alone triggered a definite negative effects on all parameters examined. On the other hand, the groups treated with resveratrol did not have statistically different values compared to the control group. Resveratrol doses induced a remarkable recovery in growth parameters including germination percentage, root elongation, and total bulb weight gain when applied with CuCl₂. In these groups, MN frequency, chromosomal aberrations, and anatomical abnormalities were alleviated, whereas the MI levels increased significantly. Moreover, lipid peroxidation level and antioxidant enzyme activities showed a marked amelioration when resveratrol and CuCl₂ were applied together. Copper compounds have become common pollutants due to their direct uses as pesticides in agricultural areas as well as their spreading to natural areas from industrial fields. The study clearly demonstrated the therapeutic potential of resveratrol against the harmful effects of CuCl₂ exposure in Allium roots. So, resveratrol could be considered as a plant-derived restorative agent for the reduction of the risks from the other copper compounds.
Afficher plus [+] Moins [-]Lipopeptides produced by Bacillus subtilis as new biocontrol products against fusariosis in ornamental plants
2018
Mihalache, Gabriela | Balaes, Tiberius | Gostin, Irina | Stefan, Marius | Coutte, François | Krier, François
In this study, we have investigated the effects of three lipopeptides (fengycin, surfactin and mycosubtilin) produced by different strains of Bacillus subtilis against the phytopathogenic fungi Fusarium oxysporum f. sp. iridacearum, which affects the ornamental bulb plant populations of Iris sp. The antifungal effects were tested using minimum inhibitory concentration assay, determination of mycelium growth and spore germination inhibition rates. Also, in vivo tests on infected rhizomes and scanning electron microscopy were employed. Mycosubtilin alone and in combination with fengycin or/and surfactin showed potent inhibitory activity at concentrations as low as 5 μg ml⁻¹ which is 100 times lower compared to Topsin M, a common chemical fungicide frequently used against fusariosis in ornamental plants. An enhancement of mycosubtilin antifungal activity was observed when it was used in combination with surfactin due to a synergistic effect. At a concentration of 20 μg ml⁻¹, mycosubtilin inhibited the growth of the mycelium up to 49% and the spore germination ability up to 26% in comparison to control. In addition, significant changes on the macro- and micro-morphology have been observed. The antifungal activity is related to the inhibition of spore germination and the irreversible damage of the hyphae cell wall. To the best of our knowledge, this is the first attempt to propose the lipopeptides as biopesticides against the fusariosis of ornamental plants.
Afficher plus [+] Moins [-]Genotoxicity assessment of raw and treated water samples using Allium cepa assay: evidence from Perak River, Malaysia
2018
Malakahmad, Amirhossein | Manan, TehSabariah Binti Abd | Sivapalan, Subarna | Khan, Taimur
Allium cepa assay was carried out in this study to evaluate genotoxic effects of raw and treated water samples from Perak River in Perak state, Malaysia. Samples were collected from three surface water treatment plants along the river, namely WTPP, WTPS, and WTPK. Initially, triplicates of equal size Allium cepa (onions) bulbs, 25–30 mm in diameter and average weight of 20 g, were set up in distilled water for 24 h at 20 ± 2 °C and protected from direct sunlight, to let the roots to grow. After germination of roots (0.5–1.0 cm in length), bulbs were transferred to collected water samples each for a 96-h period of exposure. The root physical deformations were observed. Genotoxicity quantification was based on mitotic index and genotoxicity level. Statistical analysis using cross-correlation function for replicates from treated water showed that root length has inverse correlation with mitotic indices (r = − 0.969) and frequencies of cell aberrations (r = − 0.976) at lag 1. Mitotic indices and cell aberrations of replicates from raw water have shown positive correlation at lag 1 (r = 0.946). Genotoxicity levels obtained were 23.4 ± 1.98 (WTPP), 26.68 ± 0.34 (WTPS), and 30.4 ± 1.13 (WTPK) for treated water and 17.8 ± 0.18 (WTPP), 37.15 ± 0.17 (WTPS), and 47.2 ± 0.48 (WTPK) for raw water. The observed cell aberrations were adherence, chromosome delay, C-metaphase, chromosome loss, chromosome bridge, chromosome breaks, binucleated cell, mini cell, and lobulated nuclei. The morphogenetic deformations obtained were likely due to genotoxic substances presence in collected water samples. Thus, water treatment in Malaysia does not remove genotoxic compounds.
Afficher plus [+] Moins [-]Aneugenic, clastogenic, and multi-toxic effects of diethyl phthalate exposure
2020
Demirtaş, Güray | Çavuşoğlu, Kültiğin | Yalçin, Emine
Diethyl phthalate (DEP) is a compound which is used in many industrial fields, especially in cosmetic sector and causes contamination in air, water, and soil due to its widespread usage. In this study, the potential toxic effects of DEP were investigated by using physiological, anatomical, biochemical, and cytogenetic parameters in Allium cepa. The micronucleus (MN) test specifically aimed to elucidate the aneugenic and clastogenic effects of DEP. Physiological effects were determined by germination percentage, root length, weight gain parameters, and cytogenetic effects were investigated by mitotic index (MI) and chromosomal abnormality (CA) test. Malondialdehyde (MDA) level, catalase (CAT), and superoxide dismutase (SOD) activities were investigated as oxidative damage indicators and structural changes were investigated with anatomical cross sections. For this purpose, Allium cepa bulbs were divided into four groups as control and application groups and the application groups were germinated with 1.0, 2.2, and 4.4 μM DEP for 72 h. As a result, it was determined that germination percentage, weight gain and root length decreased, CA frequency, MDA level, SOD, and CAT activities were increased in DEP-treated groups when compared with the control group. DEP has been found to induce CA in root tip cells such as fragment, chromosome bridge, c-mitosis, sticky chromosome, and unequal chromatin distribution. When MN formations induced by DEP application were examined, both large-scale and small-scale MNs were determined. MN formation in both sizes indicates that DEP has both clastogenic and aneugenic effects. And also, it was found that DEP application caused structural changes and especially anatomic damages such as necrosis in 4.4 μM DEP application. As a result, it was found that DEP caused various toxic effects depending on the dose and that A. cepa test material was a useful indicator in determining these effects.
Afficher plus [+] Moins [-]Antioxidant-oxidant balance and vital parameter alterations in an eukaryotic system induced by aflatoxin B2 exposure
2019
Çavuşoğlu, Kültiğin | Yalçin, Emine
This study was performed to evaluate the toxic effects of aflatoxin B₂ (AFB₂) on antioxidant-oxidant balance and vital parameters such as physiological, cytogenetic, and anatomical alterations in Allium cepa L. root tip cells. Toxic effects of AFB₂ on vital parameters were investigated by using the changes in weight gain, germination percentage, chromosomal aberrations (CAs), mitotic index (MI), micronucleus frequency (MN), and anatomical structure. Malondialdehyde (MDA) and reduced glutathion (GSH) levels and superoxide dismutase (SOD) and catalase (CAT) activities in root cells were investigated as antioxidant-oxidant parameters. For this aim, A. cepa bulbs were seperated into five groups as negative control, positive control, and AFB₂ treatment groups. In results, while the rate of germination percentage, weight gain, and MI rates decreased, MN and CA frequency increased in AFB₂-treated groups compared with the negative control. Most common CAs observed in AFB₂-treated groups were fragment and chromosome bridges. It was determined that in 160 μg L⁻¹ AFB₂-treated group there was a 70.8% increase in MDA and a 78.1% decrease in GSH level compared with the negative control group and these changes indicate oxidative damage. In 160 μg L⁻¹ AFB₂ treatment group, SOD and CAT activities decreased importantly due to inhibition. In anatomical examinations, it was determined that AFB₂ treatment caused some anatomical damages in A. cepa root cells such as necrosis, cell deformation, and thickening in cell wall. This study showed that AFB₂, which has the least data among aflatoxins, causes serious in vivo toxic effects in A. cepa root cells.
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