共查询到20条相似文献,搜索用时 46 毫秒
1.
Mayra Carraro Di Gregorio Keliani Bordin Pollyana Cristina Maggio de Castro Souto Carlos Humberto Corassin 《Toxin reviews》2015,34(3):142-150
Aflatoxin B1 (AFB1) is primarily biotransformed in the liver by cytochrome P450 (CYP) enzymes, which can yield either the genotoxic metabolite AFB1-8,9 epoxide that causes liver carcinogenicity or less toxic compounds. The biotransformation of AFB1 is better understood in humans, including gene expression of CYPs involved in the detoxification process. Studies on farm animals have demonstrated genes homologous to human CYPs that play similar roles in AFB1 biotransformation. This review compares the activities of the most important CYPs related to the biotransformation of AFB1 in humans, swine and domestic fowls (chickens, quail, turkeys and ducks), as well the main detoxification mechanisms in these species. 相似文献
2.
The extreme sensitivity of turkeys to aflatoxin B1 (AFB1) is associated with efficient hepatic cytochrome P-450 (P450)-mediated bioactivation, and deficient glutathione S-transferase (GST) mediated detoxification. Butylated hydroxytoluene (BHT) protects against AFB1 toxicity in turkeys through mechanisms that include competitive inhibition of P450-mediated AFB1 bioactivation. To test whether dietary BHT alters hepatic AFB1–DNA adduct formation, excretion, and bioavailability of AFB1 in vivo, turkeys were given diets with BHT (4000 ppm) for 10 days, given a single oral dose of [3H]-AFB1 (0.05 μg/g; 0.02 μCi/g), then sampled at intervals up to 24 h. Radiolabel in serum, red blood cells, liver, and breast meat was frequently lower in BHT-treated compared to control. Hepatic AFB1–DNA adducts in BHT-treated turkeys were significantly lower at 12 and 24 h. BHT-fed birds had significant higher bile efflux, though biliary radiolabel excretion was not different from control. The amount of aflatoxin M1 (AFM1) excreted in the bile was lower than in control, but BHT had no effect on the biliary excretion of AFB1, aflatoxin Q1 or glucuronide and sulfate conjugates. Thus, the chemopreventive properties of BHT may also occur through a reduction in AFB1 bioavailability in addition to inhibition of bioactivation. 相似文献
3.
The extreme sensitivity of turkeys to aflatoxin B1 (AFB1) is associated with efficient epoxidation by hepatic cytochromes P450 (P450) 1A5 and 3A37 to exo-aflatoxin B1-8,9-epoxide (exo-AFBO). The combined presence of 1A5 and 3A37, which obey different kinetic models, both of which metabolize AFB1 to the exo-AFBO and to detoxification products aflatoxin M1 (AFM1) and aflatoxin Q1 (AFQ1), respectively, complicates the kinetic analysis of AFB1 in turkey liver microsomes (TLMs). Antisera directed against 1A5 and 3A37, thereby individually removing the catalytic contribution of these enzymes, were used to identify the P450 responsible for epoxidating AFB1 in TLMs. In control TLMs, AFB1 was converted to exo-AFBO in addition to AFM1 and AFQ1 confirming the presence of functional 1A5 and 3A37. Pretreatment with anti-1A5 inhibited exo-AFBO formation, especially at low, submicromolar (~ 0.1 μM), while anti-3A37, resulted in inhibition of exo-AFBO formation, but at higher (> 50 μM) AFB1 concentrations. Metabolism in immunoinhibited TLMs resembled that of individual enzymes: 1A5 produced exo-AFBO and AFM1, conforming to Michaelis-Menten, while 3A37 produced exo-AFBO and AFQ1 following the kinetic Hill equation. At 0.1 μM AFB1, close to concentrations in livers of exposed animals, 1A5 contributed to 98% of the total exo-AFBO formation. At this concentration, 1A5 accounted for a higher activation:detoxification (50:1, exo-AFBO: AFM1) compared to 3A37 (0.15: 1, exo-AFBO: AFQ1), suggesting that 1A5 is high, while 3A4 is the low affinity enzyme in turkey liver. The data support the conclusion that P450 1A5 is the dominant enzyme responsible for AFB1 bioactivation and metabolism at environmentally-relevant AFB1 concentrations in turkey liver. 相似文献
4.
Chia-Hung Yen Jung-Hsien Hung Shih-Ping Liu Shih-Yin Chen Hsiao-Han Liu Teh-Ying Chou Ramalakshmi Darbha Ling-Ling Hsieh 《Toxicology and applied pharmacology》2009,235(3):296-187
Previously, we reported that glycine N-methyltransferase (GNMT) knockout mice develop chronic hepatitis and hepatocellular carcinoma (HCC) spontaneously. For this study we used a phosphoenolpyruvate carboxykinase promoter to establish a GNMT transgenic (TG) mouse model. Animals were intraperitoneally inoculated with aflatoxin B1 (AFB1) and monitored for 11 months, during which neither male nor female GNMT-TG mice developed HCC. In contrast, 4 of 6 (67%) male wild-type mice developed HCC. Immunofluorescent antibody test showed that GNMT was translocated into nuclei after AFB1 treatment. Competitive enzyme immunoassays indicated that after AFB1 treatment, the AFB1-DNA adducts formed in stable clones expressing GNMT reduced 51.4% compared to the vector control clones. Experiments using recombinant adenoviruses carrying GNMT cDNA (Ad-GNMT) further demonstrated that the GNMT-related inhibition of AFB1-DNA adducts formation is dose-dependent. HPLC analysis of the metabolites of AFB1 in the cultural supernatants of cells exposed to AFB1 showed that the AFM1 level in the GNMT group was significantly higher than the control group, indicating the presence of GNMT can enhance the detoxification pathway of AFB1. Cytotoxicity assay showed that the GNMT group had higher survival rate than the control group after they were treated with AFB1. Automated docking experiments showed that AFB1 binds to the S-adenosylmethionine binding domain of GNMT. Affinity sensor assay demonstrated that the dissociation constant for GNMT-AFB1 interaction is 44.9 μM. Therefore, GNMT is a tumor suppressor for HCC and it exerts protective effects in hepatocytes via direct interaction with AFB1, resulting in reduced AFB1-DNA adducts formation and cell death. 相似文献
5.
Jun Wu Weiying Xu Caihui Zhang Qing ChangXianqing Tang Kangbai LiYiqun Deng 《Biochemical pharmacology》2013
Aflatoxin B1 (AFB1) is a severe threat to human and animal health. The aflatoxin B1 aldehyde reductase (AFAR) family specifically catalyzes AFB1-dialdehyde, a toxic metabolic intermediate of AFB1, producing a nontoxic dialcohol. Although several AFARs have been found and characterized, the binding specificity of the family for AFB1-dialdehyde remains unclear. Herein, according to the published sequence, we cloned a porcine AFAR gene. Recombinant porcine AFAR was expressed and purified from Escherichia coli as hexa-histidine tagged fusion protein. Using the cloned porcine AFAR as a model, site-directed mutagenesis combined with high performance liquid chromatography studies revealed that the substitution of Trp266 with Ala resulted in almost complete loss of catalytic activity for AFB1-dialdehyde. Interestingly, the substitution of Met86 with Ala exhibited an obviously increased activity to the dialdehyde. Based on these results and by using molecular docking simulations, this work provides a structural explanation for why the AFAR family exhibits high specificity for AFB1-dialdehyde. The Trp266 residue in porcine AFAR plays a critical role in stabilizing the binding of AFB1-dialdehyde in the active pocket through the hydrophobic interaction of the side-chain indole ring of Trp266 with the fused coumarin rings of the dialdehyde molecule. The enhanced activity of M86A may be attributed to the formed π–π stacking interaction between Trp266 and the dialdehyde. In addition, other hydrophobic residues (e.g. Phe and Trp) around the dialdehyde molecule also stabilize the substrate binding. The findings may contribute to understanding the substrate specificity of the AFAR family for AFB1-dialdehyde. 相似文献
6.
This study was performed to assess the effects of dietary aflatoxin B1 (AFB1) on the growth, antioxidant and immune response, digestive enzyme activities, and intestinal morphology of Lateolabrax maculatus during a 56-day feeding trial. Four diets were formulated including 0, 0.1, 0.5, and 1.0 mg/kg of AFB1. Each diet was randomly assigned to 3 fish tanks with 40 fish per tank. Results indicated that the fish’s final body weight, weight gain rate, specific growth rate, feed intake, condition factor, viscerosomatic index, hepatosomatic index, and intestinesomatic index decreased (p < 0.01) as dietary AFB1 increased. AFB1 levels in diets increased (p < 0.05) serum total antioxidant capacity (TAOC), superoxide (SOD), catalase, malondialdehyde (MDA), alkaline phosphatase (AKP), and lysozyme (LZM), and increased (p < 0.05) the TAOC, SOD, MDA, AKP, LZM, and immunoglobulin M in the livers of the fish. Dietary AFB1 decreased (p < 0.05) intestinal trypsin activity and induced intestinal injury. In summary, dietary AFB1 up to 1.0 mg/kg was toxic to L. maculatus as judged by reduced growth, enhanced antioxidant and immune response, decreased intestinal trypsin activity, and impaired intestinal morphology. 相似文献
7.
Alpha-lipoic acid (α-LA) was evaluated in this study for its molecular mechanisms against liver oxidative damage and inflammatory responses induced by aflatoxin B1 (AFB1). Birds were randomly allocated into four groups with different diets for three weeks: a basal diet, a 300 mg/kg α-LA supplementation in a basal diet, a diet containing 74 μg/kg AFB1, and 300 mg/kg α-LA supplementation in a diet containing 74 μg/kg AFB1. In the AFB1 group, the expression of GSH-PX mRNA was down-regulated (p < 0.05), and the levels of lipid peroxide and nitric oxide were increased (p < 0.05) in the chicken livers compared to those of the control group. Additionally, the mRNA level of the pro-inflammatory factor interleukin-6 was up-regulated significantly (p < 0.05), the protein expressions of both the nuclear factor kappa B (NF-κB) p65 and the inducible nitric oxide synthase were enhanced significantly (p < 0.05) in the AFB1 group. All of these negative effects were inhibited by α-LA. These results indicate that α-LA may be effective in preventing hepatic oxidative stress, down-regulating the expression of hepatic pro-inflammatory cytokines, as well as inhibiting NF-κB expression. 相似文献
8.
Peizhou Yang Wei Xiao Shuhua Lu Suwei Jiang Zhi Zheng Danfeng Zhang Min Zhang Shaotong Jiang Shuying Jiang 《Toxins》2021,13(5)
Aflatoxins seriously threaten the health of humans and animals due to their potential carcinogenic properties. Enzymatic degradation approach is an effective and environmentally friendly alternative that involves changing the structure of aflatoxins. In this study, Trametes versicolor aflatoxin B1-degrading enzyme gene (TV-AFB1D) was integrated into the genome of Pichia pastoris GS115 by homologous recombination approach. The recombinant TV-AFB1D was expressed in engineering P. pastoris with a size of approximately 77 kDa under the induction of methanol. The maximum activity of TV-AFB1D reached 17.5 U/mL after the induction of 0.8% ethanol (v/v) for 84 h at 28 °C. The AFB1 proportion of 75.9% was degraded using AFB1 standard sample after catalysis for 12 h. In addition, the AFB1 proportion was 48.5% using AFB1-contaminated peanuts after the catalysis for 18 h at 34 °C. The recombinant TV-AFB1D would have good practical application value in AFB1 degradation in food crops. This study provides an alternative degrading enzyme for the degradation of AFB1 in aflatoxin-contaminated grain and feed via enzymatic degradation approach. 相似文献
9.
Aflatoxins (AFs) are biologically active toxic metabolites, which are produced by certain toxigenic Aspergillus sp. on agricultural crops. In this study, five edible mushroom-forming fungi were analyzed using high-performance liquid chromatography fluorescence detector (HPLC-FLD) for their ability to remove aflatoxin B1 (AFB1), one of the most potent naturally occurring carcinogens known. Bjerkandera adusta and Auricularia auricular-judae showed the most significant AFB1 removal activities (96.3% and 100%, respectively) among five strains after 14-day incubation. The cell lysate from B. adusta exhibited higher AFB1 removal activity (35%) than the cell-free supernatant (13%) after 1-day incubation and the highest removal activity (80%) after 5-day incubation at 40 °C. In addition, AFB1 analyses using whole cells, cell lysates, and cell debris from B. adusta showed that cell debris had the highest AFB1 removal activity at 5th day (95%). Moreover, exopolysaccharides from B. adusta showed an increasing trend (24–48%) similar to whole cells and cell lysates after 5- day incubation. Our results strongly suggest that AFB1 removal activity by whole cells was mainly due to AFB1 binding onto cell debris during early incubation and partly due to binding onto cell lysates along with exopolysaccharides after saturation of AFB1 binding process onto cell wall components. 相似文献
10.
It has been proposed that the consumption of lactic acid bacteria capable of binding or degrading foodborne carcinogens would reduce human exposure to these deleterious compounds. In the present study, the ability of eight strains of Lactobacillus casei to bind aflatoxin B1 in aqueous solution was investigated. Additionally, the effect of addition of bile salts to the growth medium on aflatoxin B1 binding was assessed. The eight strains tested were obtained from different ecological niches (cheese, corn silage, human feces, fermented beverage). The strains exhibited different degrees of aflatoxin binding; the strain with the highest AFB1 binding was L. casei L30, which bound 49.2% of the available aflatoxin (4.6 μg/mL). In general, the human isolates bound the most aflatoxin B1 and the cheese isolates the least. Stability of the bacterial–aflatoxin complex was assessed by repeated washings. Binding was to a limited degree (0.6–9.2% release) reversible; the L. casei 7R1–aflatoxin B1 complex exhibited the greatest stability. L. casei L30, a human isolate, was the strain least sensitive to the inhibitory effects of bile salts. Exposure of the bacterial cells to bile significant increased aflatoxin B1 binding and the differences between the strains was reduced. 相似文献
11.
Manqian Cha Erdan Wang Yangyi Hao Shoukun Ji Shuai Huang Lihong Zhao Wei Wang Wei Shao Yajing Wang Shengli Li 《Toxins》2021,13(9)
This study investigated the effect of moderate risk level (8 µg/kg) AFB1 in diet supplemented with or without adsorbents on lactation performance, serum parameters, milk AFM1 content of healthy lactating cows and the AFM1 residue exposure risk in different human age groups. Forty late healthy lactating Holstein cows (270 ± 22 d in milk; daily milk yield 21 ± 3.1 kg/d) were randomly assigned to four treatments: control diet without AFB1 and adsorbents (CON), CON with 8 μg/kg AFB1 (dry matter basis, AF), AF + 15 g/d adsorbent 1 (AD1), AF + 15 g/d adsorbent 2 (AD2). The experiment lasted for 19 days, including an AFB1-challenge phase (day 1 to 14) and an AFB1-withdraw phase (day 15 to 19). Results showed that both AFB1 and adsorbents treatments had no significant effects on the DMI, milk yield, 3.5% FCM yield, milk components and serum parameters. Compared with the AF, AD1 and AD2 had significantly lower milk AFM1 concentrations (93 ng/L vs. 46 ng/L vs. 51 ng/L) and transfer rates of dietary AFB1 into milk AFM1 (1.16% vs. 0.57% vs. 0.63%) (p < 0.05). Children aged 2–4 years old had the highest exposure risk to AFM1 in milk in AF, with an EDI of 1.02 ng/kg bw/day and a HI of 5.11 (HI > 1 indicates a potential risk for liver cancer). Both AD1 and AD2 had obviously reductions in EDI and HI for all population groups, whereas, the EDI (≥0.25 ng/kg bw/day) and HI (≥1.23) of children aged 2–11 years old were still higher than the suggested tolerable daily intake (TDI) of 0.20 ng/kg bw/day and 1.00 (HI). In conclusion, moderate risk level AFB1 in the diet of healthy lactating cows could cause a public health hazard and adding adsorbents in the dairy diet is an effective measure to remit AFM1 residue in milk and its exposure risk for humans. 相似文献
12.
Alma Vzquez-Durn María de Jesús Nava-Ramírez Daniel Hernndez-Patln Bruno Solís-Cruz Víctor Hernndez-Gmez Guillermo Tllez-Isaías Abraham Mndez-Albores 《Toxins》2021,13(11)
Adsorption of the carcinogen aflatoxin B1 (AFB1) onto agro-waste-based materials is a promising alternative over conventional inorganic binders. In the current study, two unmodified adsorbents were eco-friendly prepared from kale and lettuce agro-wastes. A dynamic gastrointestinal tract-simulated model was utilized to evaluate the removal efficiency of the sorptive materials (0.5%, w/w) when added to an AFB1-contaminated diet (100 µg AFB1/kg). Different characterization methodologies were employed to understand the interaction mechanisms between the AFB1 molecule and the biosorbents. Based on adsorption results, the biosorbent prepared from kale was the best; its maximum adsorption capacity was 93.6%, which was significantly higher than that of the lettuce biosorbent (83.7%). Characterization results indicate that different mechanisms may act simultaneously during adsorption. Non-electrostatic (hydrophobic interactions, dipole-dipole interactions, and hydrogen bonding) and electrostatic interactions (ionic attractions) together with the formation of AFB1-chlorophyll complexes appear to be the major influencing factors driving AFB1 biosorption. 相似文献
13.
Aflatoxins B1 (AFB1), deoxynivalenol (DON), fumonisin B1 (FB1), T-2 toxin (T-2), and zearalenone (ZEA) are the major foodborne mycotoxins of public health concerns. In the present study, the multiple toxic endpoints of these naturally-occurring mycotoxins were evaluated in Caenorhabditis elegans model for their lethality, toxic effects on growth and reproduction, as well as influence on lifespan. We found that the lethality endpoint was more sensitive for T-2 toxicity with the EC50 at 1.38 mg/L, the growth endpoint was relatively sensitive for AFB1 toxic effects, and the reproduction endpoint was more sensitive for toxicities of AFB1, FB1, and ZEA. Moreover, the lifespan endpoint was sensitive to toxic effects of all five tested mycotoxins. Data obtained from this study may serve as an important contribution to knowledge on assessment of mycotoxin toxic effects, especially for assessing developmental and reproductive toxic effects, using the C. elegans model. 相似文献
14.
Eduardo Madrigal-Bujaidar José Antonio Morales-González Manuel Sánchez-Gutiérrez Jeannett A. Izquierdo-Vega Alicia Reyes-Arellano Isela álvarez-González Ricardo Pérez-Pasten Eduardo Madrigal-Santillán 《Toxins》2015,7(6):2145-2158
Aflatoxins are a group of naturally-occurring carcinogens that are known to contaminate different human and animal foodstuffs. Aflatoxin B1 (AFB1) is the most genotoxic hepatocarcinogenic compound of all of the aflatoxins. In this report, we explore the capacity of β-d-glucan (Glu) to reduce the DNA damage induced by AFB1 in mouse hepatocytes. For this purpose, we applied the comet assay to groups of animals that were first administered Glu in three doses (100, 400 and 700 mg/kg bw, respectively) and, 20 min later, 1.0 mg/kg of AFB1. Liver cells were obtained at 4, 10 and 16 h after the chemical administration and examined. The results showed no protection of the damage induced by AFB1 with the low dose of the polysaccharide, but they did reveal antigenotoxic activity exerted by the two high doses. In addition, we induced a co-crystallization between both compounds, determined their fusion points and analyzed the molecules by UV spectroscopy. The data suggested the formation of a supramolecular complex between AFB1 and β-d-glucan. 相似文献
15.
AbstractIn a previous study, we reported six flavonoids isolated from the methanol extract of Urtica urens L. Patuletin, the major component, was found to have powerful anti-inflammatory and antimicrobial activity. We have now investigated whether patuletin also has antioxidant activity and free radical scavenging effects in rats treated with aflatoxin B1 (AFB1). Male Sprague-Dawley rats (60) were assigned to 6 experimental groups including a control group and groups treated for 10 days with patuletin at low dose (7.5 mg/kg b.w) or high dose (10 mg/kg b.w) with or without AFB1 (2 mg/kg b.w). Blood samples were collected at the end of the experimental period for biochemical analysis. The results showed significant changes typical to aflatoxicosis in rats treated only with AFB1. Patuletin at the two tested doses caused an increase in glutathione peroxidase (GPx) and superoxide dismutase (SOD); high doses also caused an increase in liver and kidney enzymes, except total bilirubin (TB), which was in the normal value of the control animals. On the other hand, these enzymes were comparable to the controls in rats treated with low doses. Cotreatment of AFB1 and patuletin resulted in a significant improvement in all parameters tested. We conclude that patuletin possesses an antioxidant activity and free radical scavenging effects in AFB1-treated rats that can be observed at a dose as low as 7.5 mg/kg b.w. 相似文献
16.
17.
Alessandra V. Jager Fernando G. Tonin Pollyana C. M. C. Souto Rafaela T. Privatti Carlos A. F. Oliveira 《Toxins》2014,6(7):1996-2007
In the present study, a longitudinal assessment was carried out to evaluate the short-term human exposure to aflatoxins in Pirassununga region, São Paulo, Brazil, by determination of urinary aflatoxins by a liquid chromatography coupled to mass sprectrometry (UPLC-MS/MS) method. Sixteen volunteers with ages ranging from 14 to 55 years old were instructed to collect the early morning first urine four times every three months, from June 2011 to March 2012, totaling 64 samples. Aflatoxin M1 (AFM1) was found in 39 samples (61%) at levels ranging from 0.19 to 12.7 pg·mg−1 creatinine (mean: 1.2 ± 2.0 pg·mg−1 creatinine). Residues of aflatoxins B1, B2, G1, G2 and aflatoxicol were not identified in any urine sample. No significant difference was found among the AFM1 mean levels in urine samples collected in the four sampling periods. The levels of AFM1 found in urine samples indicate a low short-term exposure of the population studied to aflatoxins through the diet, although further investigations are needed to assess other long-term biomarkers of exposure to AFB1. 相似文献
18.
Xing Qin Xiaoyun Su Tao Tu Jie Zhang Xiaolu Wang Yaru Wang Yuan Wang Yingguo Bai Bin Yao Huiying Luo Huoqing Huang 《Toxins》2021,13(6)
The co-occurrence of multiple mycotoxins, including aflatoxin B1 (AFB1), zearalenone (ZEN) and deoxynivalenol (DON), widely exists in cereal-based animal feed and food. At present, most reported mycotoxins degrading enzymes target only a certain type of mycotoxins. Therefore, it is of great significance for mining enzymes involved in the simultaneous degradation of different types of mycotoxins. In this study, a dye-decolorizing peroxidase-encoding gene BsDyP from Bacillus subtilis SCK6 was cloned and expressed in Escherichia coli BL21/pG-Tf2. The purified recombinant BsDyP was capable of oxidizing various substrates, including lignin phenolic model compounds 2,6-dimethylphenol and guaiacol, the substrate 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid), anthraquinone dye reactive blue 19 and azo dye reactive black 5, as well as Mn2+. In addition, BsDyP could efficiently degrade different types of mycotoxins, including AFB1, ZEN and DON, in presence of Mn2+. More important, the toxicities of their corresponding enzymatic degradation products AFB1-diol, 15-OH-ZEN and C15H18O8 were significantly lower than AFB1, ZEN and DON. In summary, these results proved that BsDyP was a promising candidate for the simultaneous degradation of multiple mycotoxins in animal feed and food. 相似文献
19.
Umberto Bernabucci Luciana ColavecchiaPier Paolo Danieli Loredana BasiricòNicola Lacetera Alessandro NardoneBruno Ronchi 《Toxicology in vitro》2011,25(3):684-691
Mycotoxins are secondary metabolites having a high cytotoxic potential. They are produced by molds and released in food and feed. To date, the mechanisms underlying the mycotoxin-induced cytotoxicity have not been fully clarified. The induction of oxidative stress, as a possible mechanism, has been postulated. This in vitro study was focused on the effect of two widely occurring mycotoxins, aflatoxin B1 (AFB1) and fumonisin B1 (FB1), on the oxidative status of bovine peripheral blood mononuclear cells (PBMC) incubated for 2 and 7 days at different levels of AFB1 (0, 5 and 20 μg/ml) and FB1 (0, 35 and 70 μg/ml). Reactive oxygen metabolites (ROM), intracellular thiols (SH), malondialdehyde (MDA) and gene expression of cytoplasmic superoxide dismutase (SOD) and glutathione peroxidase (GSHPX-1) were measured on PBMC after incubation. The highest concentration of AFB1 and all concentrations of FB1 caused an increase (p < 0.05) of intracellular ROM without any time dependent effect. Intracellular SH decreased with 20 μgAFB1/ml (p < 0.05) and the effect was particularly marked after 7 days of exposure. Intracellular SH were not affected by FB1 even though a lower (p < 0.05) SH level after 2 days exposure than after 7 days was observed. MDA increased (p < 0.05) in AFB1 or FB1 treated PBMC. The exposure to FB1 for 7 days increased MDA (p < 0.05) only in cells treated with 70 μg/ml. Exposure of PBMC to AFB1 reduced SOD mRNA while FB1 decreased both SOD and GSHPX-1 mRNA abundance. These results demonstrate that, even though by different mechanisms, AFB1 and FB1 may induce cytotoxicity through an impairment of the oxidative status of PBMC. 相似文献
20.
Le Wang Wei Huang Yu Sha Haicheng Yin Ying Liang Xin Wang Yan Shen Xingquan Wu Dapeng Wu Jinshui Wang 《Toxins》2021,13(7)
Bacillus sp. H16v8 and Bacillus sp. HGD9229 were identified as Aflatoxin B1 (AFB1) degrader in nutrient broth after a 12 h incubation at 37 °C. The degradation efficiency of the two-strain supernatant on 100 μg/L AFB1 was higher than the bacterial cells and cell lysate. Moreover, degradations of AFB1 were strongly affected by the metal ions in which Cu2+ stimulated the degradation and Zn2+ inhibited the degradation. The extracellular detoxifying enzymes produced by co-cultivation of two strains were isolated and purified by ultrafiltration. The molecular weight range of the detoxifying enzymes was 20–25 kDa by SDS-PAGE. The co-culture of two strains improved the total cell growth with the enhancement of the total protein content and detoxifying enzyme production. The degradation efficiency of the supernatant from mixed cultures increased by 87.7% and 55.3% compared to Bacillus sp. H16v8 and HGD9229, individually. Moreover, after the degradation of AFB1, the four products of the lower toxicity were identified by LC-Triple TOF-MS with the two proposed hypothetical degradation pathways. 相似文献