Assessment of cytotoxic and genotoxic effects of enniatin-A in vitro

Enniatin A (EN-A) is a Fusarium mycotoxin which is a common contaminant in grains and especially in maize and it causes serious loss of product. The aim of this study was to investigate the cytotoxic effects using 3-(4,5-dimethylthiazolyl-2)-2,5 diphenyltetrazolium bromide (MTT) assay in human cervix carcinoma (HeLa) cell line, and genotoxic effects of EN-A using chromosome aberrations (CAs), sister chromatid exchanges (SCEs), micronuclei (MN) and comet assays in human lymphocytes. The cells were treated with 0.07, 0.14, 0.29, 0.57, 1.15, 2.29, 4.59 and 9.17 μM concentrations of EN-A. It exhibited cytotoxic effects in HeLa cell lines especially when the concentrations were increased. The half-inhibitory value (IC₅₀) was determined as 1.15 μM concentration for 24 h and 0.57 μM concentration for 48 h. However, EN-A failed to affect the frequency of CAs, SCEs and MN in human lymphocytes. Only a slight increase was observed in the frequency of SCEs at 0.57 μM concentration over 48 h. The replication (RI) and nuclear division (NDI) indices were not affected. On the contrary, EN-A decreased the mitotic index (MI) significantly at all concentrations compared to the negative control and solvent control (except at 0.29 μM for 24 h, and except at 0.14, 0.29 and 0.57 μM for 48 h). Treatments over 2.29 μM showed toxic effects in human lymphocytes. EN-A significantly increased comet tail intensity (except at 0.07 and 0.57 μM) in isolated human lymphocytes. The results of this study demonstrate that EN-A has an obvious cytotoxic effect especially when the EN-A concentration was increased. In addition, EN-A could exhibit a mild genotoxic effect.     

A whole cell electrochemical biosensor for water genotoxicity bio-detection

This work presents a novel micro-fluidic whole cell biosensor for water toxicity analysis. The biosensor presented here is based on bacterial cells that are genetically “tailored” to generate a sequence of biochemical reactions that eventually generate an electrical signal in the presence of genotoxicants. The bacterial assay was affected by toxicant contaminated water for an induction time that ranged between 30 min and 120 min. Enzymatic substrate (pAPP) was added to the assay generating the electrochemical active material (pAP) only when toxicants are sensed by the bacteria. The bacteria were integrated onto a micro-chip that was manufactured by MEMS technology and comprises various micro-chambers with volume ranging between 2.5 nl and 157 nl with electrode radius between 37.5 μm and 300 μm. We describe the biochip operation, its electrochemical response to calibration solutions as well as to the whole cell assays. The potential use of the whole cell biochip for toxicity detection of two different genotoxicants, nalidixic acid (NA) and 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), is demonstrated. We demonstrate minimal toxicant detection of 10 μg/ml for NA using 30 min for induction and 0.31 μM for IQ using 120 min for induction, both 3 min after the addition of the substrate material.     

王浆酸冻干粉的安全性毒理学评价

研究王浆酸冻干粉的食用安全性,为促进其合理开发利用提供科学依据。根据《保健食品检验与评价技术规范》对王浆酸冻干粉进行急性经口毒性试验,遗传毒性试验(Ames试验、小鼠骨髓细胞微核试验、小鼠精子畸形试验)和大鼠30 d喂养试验对王浆酸冻干粉的食用安全性进行毒理学评价。王浆酸冻干粉对雌、雄小鼠的急性经口LD_(50)20 mg/kg.bw;Ames试验、小鼠骨髓微核试验和小鼠精子畸形试验3项遗传毒性试验结果均为阴性;大鼠30 d喂养实验中,实验动物生长情况良好,血液学检查结果、生化学检查结果、主要脏体比及组织学检查结果与对照组相比,均无明显差异(p0.05)。病理组织学检查未发现王浆酸对大鼠主要脏器产生组织结构的改变。王浆酸冻干粉无毒,无遗传毒性及亚急性毒性作用,具有较高的食用安全性。     

Effect of ozone and ozone/activated carbon treatments on genotoxic activity of naphthalenesulfonic acids

Naphthalenesulfonic compounds are widely used, mainly by the textile industry in the synthesis of azoic colorants. The presence of the sulfonic group is known to endow these compounds with high water‐solubility and low biodegradability, although its influence on their genotoxic activity is unknown. The use of energetic oxidants is recommended for the degradation of organic compounds which are refractory to biological treatment. Ozone and ozone/activated carbon have been proposed as the best alternatives to remove these compounds. The results showed that the more sulfonic groups there are on the aromatic ring of this family of contaminants, the lower is their genotoxic activity. All the compounds studied presented genotoxic activity at elevated concentrations. Ames test results indicate that DNA damage was produced by substitution of nitrogenated bases. The system based on the combined use of ozone and activated carbon was the most efficacious in the depuration of water containing these contaminants. This approach rapidly degraded the naphthalenesulfonic acids, eliminated their genotoxic activity and reduced their organic material content using low doses of ozone. © 2002 Society of Chemical Industry     

Pilot study on combined process of catalytic ozonation and biological activated carbon for organic pollutants removal

A combined process of catalytic ozonation in the presence of a novel heterogeneous catalyst and biological activated carbon was investigated for the removal of priority control organic pollutants, the reduction of genotoxicity, and the improvement of biodegradable dissolved organic carbon (BDOC). Results confirm that the catalytic ozonation has higher effectiveness for the removal of refractory harmful organic pollutants, the reduction of genotoxicity and the increase of bio-degradability of organics than ozonation alone, which results in lower pollution load for subsequent biological activated carbon process, and then leads to less organic pollutants penetrating biological activated carbon. The novel catalytic ozonation with this combined process exhibits excellent performance to guarantee the safety of drinking water.     

丙烯酰胺代谢机理及其体内毒性防护的研究进展

丙烯酰胺是一种潜在的致癌物,自2002年被报道在热加工食品中高含量存在后,引起了国际社会的广泛关注.有研究发现,丙烯酰胺对人体的危害主要是由于其代谢产物环氧丙酰胺造成的.本文综述了近年来在环氧丙酰胺的分析方法、代谢机理、基因毒性等方面的研究进展;并结合利用天然产物抑制丙烯酰胺体内毒性的研究成果,对其危害的深层次防护提出...     

Molecular Toxicology of Substances Released from Resin�CBased Dental Restorative Materials

Resin-based dental restorative materials are extensively used today in dentistry. However, significant concerns still remain regarding their biocompatibility. For this reason, significant scientific effort has been focused on the determination of the molecular toxicology of substances released by these biomaterials, using several tools for risk assessment, including exposure assessment, hazard identification and dose-response analysis. These studies have shown that substances released by these materials can cause significant cytotoxic and genotoxic effects, leading to irreversible disturbance of basic cellular functions. The aim of this article is to review current knowledge related to dental composites’ molecular toxicology and to give implications for possible improvements concerning their biocompatibility.     

体外生物测定法在食品接触材料安全性评价中的应用研究进展

体外生物测定法是利用酵母、细菌、细胞等进行的生物体外短期毒性实验,可以有效针对生物体某一特异性效应,评价测试物的危害性以及探索其毒性作用机制。由于体外生物测定法可以提供食品接触材料迁移物（混合物）整体实际危害的综合信息,因此,近年来被越来越多地应用于食品接触材料的危害评估,尤其集中在细胞毒性、遗传毒性和内分泌干扰这3 类毒理学终点。本文重点综述了这3 类体外生物测定方法的基本原理,以及近20年来其在食品接触材料提取物危害评价中的应用研究进展,以期为今后食品接触材料生物学安全性评价的相关研究提供理论参考。     

赤霉素GA3急性毒性和遗传毒性

目的：研究赤霉素GA3的急性毒性和遗传毒性,为合理使用赤霉素以及赤霉素残留限量标准的制定提供参考。方法：采用最大剂量耐受法测定赤霉素GA3的急性毒性,采用蚕豆根尖细胞微核实验、小鼠骨髓细胞微核实验和小鼠精子畸形实验测定赤霉素GA3的遗传毒性。结果：给昆明种小鼠经口灌胃赤霉素GA3,LD50＞15 000 mg/kg;赤霉素GA3在质量浓度为0.1～2.0 mg/L范围内时,蚕豆根尖细胞微核率呈上升趋势,与阴性对照组相比均存在极显著差异,且微核指数均＞1.5;7.5 g/kg赤霉素GA3对雌、雄小鼠的骨髓细胞微核率分别为7.47‰、7.07‰,小鼠精子畸形率为5.47%,与阴性对照组相比均存在极显著差异（P＜0.01）。结论：赤霉素GA3的急性毒性虽然比较低,属于无毒级,但是在较高剂量条件下对植物细胞、动物的体细胞与生殖细胞均具有遗传毒性,应尽快制定赤霉素GA3使用限量标准。     

Human Hazard Assessment Using Drosophila Wing Spot Test as an Alternative In Vivo Model for Genotoxicity Testing—A Review

Genomic instability, one of cancer’s hallmarks, is induced by genotoxins from endogenous and exogenous sources, including reactive oxygen species (ROS), diet, and environmental pollutants. A sensitive in vivo genotoxicity test is required for the identification of human hazards to reduce the potential health risk. The somatic mutation and recombination test (SMART) or wing spot test is a genotoxicity assay involving Drosophila melanogaster (fruit fly) as a classical, alternative human model. This review describes the principle of the SMART assay in conjunction with its advantages and disadvantages and discusses applications of the assay covering all segments of health-related industries, including food, dietary supplements, drug industries, pesticides, and herbicides, as well as nanoparticles. Chemopreventive strategies are outlined as a global health trend for the anti-genotoxicity of interesting herbal extract compounds determined by SMART assay. The successful application of Drosophila for high-throughput screening of mutagens is also discussed as a future perspective.