Affiner votre recherche
Résultats 1-7 de 7
Fungal biodegradation of the N-nitrosodimethylamine precursors venlafaxine and O-desmethylvenlafaxine in water
2019
Llorca, Marta | Castellet-Rovira, Francesc | Farré, María-José | Jaén-Gil, Adrián | Martínez-Alonso, Maira | Rodríguez-Mozaz, Sara | Sarrà, Montserrat | Barceló, Damià
Antidepressant drugs such as Venlafaxine (VFX) and O-desmethylvenlafaxine (ODMVFX) are emerging contaminants that are commonly detected in aquatic environments, since conventional wastewater treatment plants are unable to completely remove them. They can be precursors of hazardous by-products, such as the carcinogenic N-nitrosodimethylamine (NDMA), generated upon water chlorination, as they contain the dimethylamino moiety, necessary for the formation of NDMA. In this study, the capability of three white rot fungi (Trametes versicolor, Ganoderma lucidum and Pleurotus ostreatus) to remove both antidepressants from water and to decrease NDMA formation potential was investigated. Furthermore, transformation by-products (TPs) generated along the treatment process were elucidated and also correlated with their NDMA formation potential.Very promising results were obtained for T. versicolor and G. lucidum, both being able to remove up to 100% of ODMVFX. In the case of VFX, which is very recalcitrant to conventional wastewater treatment, a 70% of removal was achieved by T. versicolor, along with a reduction in NDMA formation potential, thus decreasing the associated problems for human health and the environment. However, the NDMA formation potential remained practically constant during treatment with G. lucidum despite of the equally high VFX removal (70%). This difference was attributed to the generation of different TPs during both fungal treatments. For example, G. lucidum generated more ODMVFX, which actually has a higher NDMA formation potential than the parent compound itself.
Afficher plus [+] Moins [-]Protective effects of Ganoderma lucidum triterpenoids on oxidative stress and apoptosis in the spleen of chickens induced by cadmium
2019
Teng, Xiangqi | Zhang, Weiqian | Song, Yangyang | Wang, Haibin | Ge, Ming | Zhang, Ruili
Cadmium (Cd) is a heavy metal that poses a huge potential threat to human and animal health. Therefore, it is necessary to study its damage mechanism. In the present study, we have examined the protective effects of Ganoderma lucidum triterpenoids on oxidative stress and apoptosis in the spleen of chickens induced by Cd. One hundred and twenty healthy Hailan white chickens (7-day-old) were randomly divided into the following four groups: control group, Cd group, triterpenoid group, and Cd–triterpenoid group. The chickens were euthanized on the 20th, 40th, and 60th days, and the spleens were removed. Cd and malondialdehyde (MDA) content, antioxidant enzyme (superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px)) activities, and inflammatory factor (tumor necrosis factor alpha (TNF-α) and interleukin (IL-1β and IL-6)) and apoptotic factor (caspase-3, BAX, and Bcl-2) expressions were detected. The results showed that Ganoderma lucidum triterpenoids could reduce the content of Cd and MDA; increase the antioxidant enzyme activities (SOD and GSH-Px); decrease the expression of inflammatory factors (TNF-α) and interleukin (IL-1β and IL-6); increase the expression of apoptotic factor (Bcl-2); and decrease the expression of apoptotic factors (caspase-3 and Bax). It showed that the triterpenoids of Ganoderma lucidum had significant protective effects on oxidative stress and apoptosis of chicken spleen, which provided a theoretical basis for further prevention and treatment of cadmium poisoning.
Afficher plus [+] Moins [-]Decolourization of Congo Red by Ganoderma lucidum Laccase: Evaluation of Degradation Products and Toxicity
2015
Mota, Thatiane Rodrigues | Kato, Camila Gabriel | Peralta, Rosely Aparecida | Bracht, Adelar | de Morais, Gutierrez Rodriguez | Baesso, Mauro Luciano | de Souza, Cristina Giatti Marques | Peralta, Rosane Marina
Several laccases from different sources have been used in dye decolourization processes. However, only in a reduced number of studies have efforts been done to identify the metabolites produced by the enzymatic treatment as well as to evaluate the toxicity of degradation products. Taking these gaps into account, the objective of this work was to use a laccase from Ganoderma lucidum in the decolourization of the synthetic dye Congo red (C.I. No. 22120, Direct Red 28), largely used in the textile industry. After 6 h of treatment at pH 4.0 and 40 °C, the enzyme was able to decolourize 80 % of Congo red. Fourier transform infrared spectroscopy (FTIR), photoacoustic spectroscopy (PAS) and mass spectrometry allow concluding that laccase effectively changed the structure of Congo red, reducing the colour by modifying the chromophore groups and other parts of the molecule. Several degradation products with m/z ⁺ ranging from 298 to 745 were identified. It is proposed that the first degradation step could be an asymmetric cleavage of the azo bond present in the Congo red structure forming the intermediate with m/z ⁺ 298. The results also suggest a reduction in the toxicity of Congo red after laccase treatment, as indicated by the lettuce seed germination model. In conclusion, G. lucidum laccase could be used in a novel azo dye bioremediation strategy.
Afficher plus [+] Moins [-]Metal concentration and health risk assessment of wild mushrooms collected from the Black Sea region of Turkey
2020
Sarikurkcu, Cengiz | Akata, Ilgaz | Guven, Gulsen | Tepe, Bektas
Mushrooms are rich sources of organic nutrients (especially proteins). However, they can excessively accumulate metals in their fruiting bodies that pose a risk to human health. The aim of this study was the determination of Cd, Co, Cu, Fe, Mn, Ni, Pb, and Zn contents, daily intake, and health risk index values of some mushroom species collected from the eastern Black Sea region of Turkey (Arsin, Trabzon). The samples were collected from hazelnut gardens that are free from industrial pollution and have a low population density. As a result of elemental analysis, it was determined that the concentration ranges of Cd, Co, Cu, Fe, Mn, Ni, Pb, and Zn in the mushrooms were as follows: 0.29–9.11, 0.04–3.70, 0.01–8.29, 0.18–20.82, 3.1–79.8, 5.2–673.0, 14.9–752.0, 63.0–7769.0 mg/kg dry weight. Daily intakes of all the elements were found to be below the reference dose in Fistulina hepatica, Hydnum repandum, Macrolepiota procera, and Tapinella atrotomentosa. Amanita caesarea, Agrocybe praecox, Amanita vaginata, Cantharellus cibarius, Craterellus cornucopioides, Daedalea quercina, Gymnopus dryophilus, Ganoderma lucidum, and Infundibulicybe gibba were found to have high risk index values especially with respect to Cd, Co, and Pb. According to Pearson correlation analysis, the correlations between Fe–Mn (0.840, p < 0.01) and Pb–Ni (0.7540, p < 0.01) couples are significant.
Afficher plus [+] Moins [-]Optimization of mycoremediation treatment for the chemical oxygen demand (COD) and ammonia nitrogen (AN) removal from domestic effluent using wild-Serbian Ganoderma lucidum (WSGL)
2021
Mooralitharan, Silambarasi | Hanafiah, Zarimah Mohd | Manan, Teh Sabariah Binti Abd | Hasan, Hassimi Abu | Jensen, Henriette S. | Wan-Mohtar, Wan Abd Al Qadr Imad | Mohtar, Wan Hanna Melini Wan
The fungi-based technology, wild-Serbian Ganoderma lucidum (WSGL) as myco-alternative to existing conventional microbial-based wastewater treatment is introduced in this study as a potential alternative treatment. The mycoremediation is highly persistent for its capability to oxidatively breakdown pollutant substrates and widely researched for its medicinal properties. Utilizing the nonhazardous properties and high degradation performance of WSGL, this research aims to optimize mycoremediation treatment design for chemical oxygen demand (COD) and ammonia nitrogen (AN) removal in domestic wastewater based on proposed Model 1 (temperature and treatment time) and Model 2 (volume of pellet and treatment time) via response surface methodology (RSM). Combined process variables were temperature (⁰C) (Model 1) and the volume of mycelial pellets (%) (Model 2) against treatment time (hour). Response variables for these two sets of central composite design (CCD) were the removal efficiencies of COD (%) and AN (%). The regression line fitted well with the data with R² values of 0.9840 (Model 1-COD), 0.9477 (Model 1-AN), 0.9988 (Model 2-COD), and 0.9990 (Model 2-AN). The lack of fit test gives the highest value of sum of squares equal to 9494.91 (Model 1-COD), 9701.68 (Model 1-AN), 23786.55 (Model 2-COD), and 13357.02 (Model 2-AN), with probability F values less than 0.05 showing significant models. The optimized temperature for Model 1 was at 25 °C within 24 h of treatment time with 95.1% COD and 96.3% AN removals. The optimized condition (temperature) in Model 1 was further studied in Model 2. The optimized volume of pellet for Model 2 was 0.25% in 24-h treatment time with 76.0% COD and 78.4% AN removals. Overall, the ascended sequence of high volume of pellet considered in Model 2 will slow down the degradation process. The best fit volume of pellet with maximum degradation of COD and AN is equivalent to 0.1% at 25 °C in 24 h. The high performance achieved demonstrates that the mycoremediation of G. lucidum is highly potential as part of the wastewater treatment system in treating domestic wastewater of high organic loadings.
Afficher plus [+] Moins [-]Elemental distribution including toxic elements in edible and inedible wild growing mushrooms from South Africa
2019
Rasalanavho, Muvhango | Moodley, Roshila | Jonnalagadda, Sreekantha B.
Macro-elements (Ca, Fe, K, Mg and Na) and trace elements including some toxic (As, Be, Cd, Co, Cu, Mn, Ni, Pb, Se and Zn) were determined in edible and inedible wild-growing mushrooms (Amanita rubescens, Auricularia polytricha, Boletus edulis, Boletus mirabilis, Clavulina cristata, Helvella crispa, Lactarius deliciosus, Suillus luteus, Termitomyces microcarpus, Termitomyces reticulatus, Termitomyces clypeatus, Termitomyces umkowaanii, Amanita foetidissima, Amanita muscaria, Amanita pantherina, Aseroe rubra, Chlorophyllum molybdites, Ganoderma lucidum, Gymnopilus junonius, Hypholoma fasciculare, Lentinus villosus, Lepista caffrorum, Pycnoporus sanguineus, Panaeolus papilionaceus, Pisolithus tinctorius, Pleurotus ostreatus, Podaxis pistillaris, Russula sardonia, Scleroderma citrinum, Scleroderma michiganense). Analyses of samples were carried out using inductively coupled plasma-optical emission spectrometry. The elemental content in both edible and inedible mushrooms, in decreasing order, was found to be K >> Na > Ca > Mg > Fe > Mn > Zn > Cu > Se > Co > Ni > Be > Pb ≥ Cd > As. Our study revealed that the accumulation of metals from the soil is independent of whether mushrooms are edible or inedible as uptake is dependent on the soil quality and its environment. Edible mushroom species studied were found to be rich in Se (145–836% towards the RDA) with B. edulis being rich in it, C. cristata in Cu, S. luteus in Fe and H. crispa in Zn, and all contained low concentrations of toxic metals making them suitable for human consumption.
Afficher plus [+] Moins [-]Bio-based degradation of emerging endocrine-disrupting and dye-based pollutants using cross-linked enzyme aggregates
2017
Vēlāyutan̲, T. A. | Asgher, Muhammad | Iqbal, Hafiz M. N. | Hu, Hongbo | Zhang, Xuehong
In this study, manganese peroxidase (MnP) from an indigenous white-rot fungus Ganoderma lucidum IBL-05 was insolubilized in the form of cross-linked enzyme aggregates (CLEAs) using various aggregating agents, i.e., acetone, ammonium sulfate, ethanol, 2-propanol, and tert-butanol, followed by glutaraldehyde (GA) cross-linking. The precipitant type, MnP, and GA concentrations affected the CLEAs activity recovery and aggregation yield. Among precipitants used, acetone appeared to be the most efficient aggregation agent, providing the highest activity recovery and aggregation yield of 31.26 and 73.46%, respectively. Optimal cross-linking was noticed using 2.0% (v/v) GA and 8:1 (v/v) MnP to GA ratio at 3.0 h cross-linking time under continuous agitation at 4 °C. The highest recovered activity and aggregation yield were determined to be 47.57 and 81.26%, respectively. The MnP-CLEAs, thus synthesized, were tested to investigate their bio-catalytic capacity for removing two known endocrine-disrupting chemicals (EDCs), e.g., nonylphenol and triclosan in a packed bed reactor system. The insolubilized MnP efficiently catalyzed the biodegradation of both EDCs, transforming over 80% in the presence of MnP-based system. A maximal of 100% decolorization was recorded for Sitara textile (SIT-based) effluent, followed by 95.5% for Crescent textile (CRT-based) effluent, 88.0% for K&N textile (KIT-based) effluent, and 84.2% for Nishat textile (NIT-based) effluent.
Afficher plus [+] Moins [-]