On the Chemistry,Toxicology and Genetics of the Cyanobacterial Toxins,Microcystin, Nodularin,Saxitoxin and Cylindrospermopsin

The cyanobacteria or “blue-green algae”, as they are commonly termed, comprise a diverse group of oxygenic photosynthetic bacteria that inhabit a wide range of aquatic and terrestrial environments, and display incredible morphological diversity. Many aquatic, bloom-forming species of cyanobacteria are capable of producing biologically active secondary metabolites, which are highly toxic to humans and other animals. From a toxicological viewpoint, the cyanotoxins span four major classes: the neurotoxins, hepatotoxins, cytotoxins, and dermatoxins (irritant toxins). However, structurally they are quite diverse. Over the past decade, the biosynthesis pathways of the four major cyanotoxins: microcystin, nodularin, saxitoxin and cylindrospermopsin, have been genetically and biochemically elucidated. This review provides an overview of these biosynthesis pathways and additionally summarizes the chemistry and toxicology of these remarkable secondary metabolites.     

节约环保型食品毒理学综合性·设计型实验教学体系构建

为进一步适应社会和学科发展需要,提高食品毒理学的实验教学效果,分析了食品毒理学实验教学设计现状,从实验教学内容、方法、技能训练等体系进行了节约环保型食品毒理学综合性、设计型实验教学改革,充分开发实验动物使用价值,采用视频教学法和模拟仿真实验室教学,增加探索性实验设计,进一步增强学生的技能训练,为我国的食品质量与安全专业培养优秀人才。     

Establishment of the Rex Rabbit Fluorosis Model and Detection of the Fluoride Content in Organs

In order to study the influence of different doses of sodium fluoride on rex rabbit,rex rabbit fluorosis model was established and the fluorine contents of blood,bone,liver,kidney and other organs in rex rabbit were examined to provide a theoretical reference for the further research. Rex rabbits (age (30±5) days,weight (1.1±0.2) kg) were divided into three groups:Control group,test group Ⅰ (10 mg/(kg·d) NaF group) and test group Ⅱ (20 mg/(kg·d) NaF group). The tests lasted 100 d. The results showed that,on the 100th day,fluoride contents of bone and tooth were significantly different (P<0.05),and they were positively correlated with the time and intake of fluoride;The fluoride contents of kidney and liver were slightly different (P>0.05),and they were not significantly different between both test groups (P>0.05).The fluoride contents of blood were not significantly different between group Ⅰ and group Ⅱ (P>0.05),but both had no significant changes compared with control group (P<0.05). Sodium fluoride as a fluoride source could be used to simulate the natural state of rex rabbit fluorine poisoning. The fluoride accumulating ability in bone and tooth were stronger while the ability in blood,liver and kidney were weaker.     

獭兔氟中毒模型的建立及各器官氟含量测定

为研究不同剂量氟化钠对獭兔的影响,试验建立獭兔氟中毒模型并对獭兔血液、骨骼、肝脏、肾脏等器官氟含量进行测定。试验獭兔日龄（30±5） d,体重（1.1±0.2） kg,数量24只,分为3组：对照组、试验Ⅰ组（10 mg/（kg·d）氟化钠组）和试验Ⅱ组（20 mg/（kg·d）氟化钠组）,试验共100 d。结果表明,试验第100天测定的骨骼和牙齿氟含量在各组之间均差异显著（P<0.05）,且骨骼和牙齿的含氟量随时间和摄入氟剂量的增加而递增;肾脏和肝脏氟含量在各组之间均差异不显著（P>0.05）;试验Ⅰ、Ⅱ组间血液氟含量差异不显著（P>0.05）,但都与对照组差异显著（P<0.05）。氟化钠作为氟化物来源可用来建立獭兔自然状态氟中毒症,骨骼和牙齿累积氟能力强,血液、肝脏和肾脏累积氟能力弱。本试验为进一步研究獭兔氟中毒及其防制提供了理论参考。     

含铬鱼肉质遗传毒理学检测与评价

以氯化铬0．5mgCr/kg饵料喂饲鲤二个月,以全鱼为受试物,不同剂量给小鼠一次灌胃,观察2周。急性毒性实验证明该样品为无毒物质。遗传毒理学检测,小鼠骨髓嗜多微核试验为阴性;小鼠睾丸染色体畸变分析末见染色体损伤;小鼠伤寒沙门氏菌/微粒体试验（Ames）在不加与加S9代谢活化系统的条件下,对Ames试验菌球均呈阴性结果。上述三项检测结果表明：铬对鱼无致突变作用,从遗传毒理学角度认为食用是安全的。     

华南野生蔬菜守宫木的毒理学研究

试验以华南主要野生蔬菜守宫木为材料,对其毒理学进行了探讨.结果表明:小鼠经口服LD50大于10.00 g.kg-1;守宫木引起小白鼠的精子畸形率增多;守宫木30 d喂养对SD大白鼠的肝、肾、脾、心、肺、睾丸等器官有损伤,且组间差异显著,呈一定的剂量反映关系,试验表明30 d喂养守宫木最大无作用剂量组应小于2.5 g.kg-1.说明守宫木可能具有蓄积毒性,不适宜作为蔬菜长期日常食用.     

甲醛对波斯顿蕨生长的毒理学

以波斯顿蕨为材料,通过测定其在不同浓度甲醛处理下的各种生理指标的变化情况,研究蕨类植物吸收室内甲醛的能力。结果表明,在不同浓度甲醛的处理下,叶绿素含量呈先升后降趋势,而叶绿素a/b比值呈先降低后升高的趋势,MDA含量逐渐累积,脯氨酸含量呈增加趋势。波斯顿蕨对低浓度的甲醛具有一定的抗性。     

丝胶蛋白滋养润白保湿面膜的毒理学试验结果

本品以丝胶蛋白为主要配料,经特殊工艺提取处理和配制,研制成功产品"丝胶蛋白滋养润白保湿面膜"。依据卫生部《化妆品卫生规范》(2007),对它进行了毒理学试验。本文简要介绍了丝胶蛋白滋养润白保湿面膜的毒理学试验检测结果。