转基因食品及其安全性评价

随着我国转基因农作物进口数量不断增加,以转基因农作物为原料的食品在市场上所占有份额逐渐增大,转基因食品安全性越来越受到人们关注;本文综述转基因食品发展现状、安全性评价、营养问题及各国政府对于转基因食品采取的管理措施和标识管理,并对转基因食品发展前景进行展望。     

转基因食品安全性评价

转基因食品与普通食品的重要差异在于前者含有采用DNA重组技术导入的外源基因。近年来随着大量的转基因食品被批准商业化使用 ,转基因食品的安全性问题也越来越受到关注。本文对影响转基因食品安全性的重要因素———外源基因及其编码蛋白的食品安全性进行了简要的分析讨论     

南瓜叶浓缩蛋白制品的食用安全性初步评价

采用我国《食品安全性毒理学评价程序》中所规定的标准方法和实验模型,对南瓜叶浓缩蛋白制品的食用安全性进行评价.结果显示,该产品小鼠经口LD50值大于21.501g/kg·bw,属无毒级;小鼠30d喂养未显示任何毒副作用.因此,该产品对实验动物不具有急性毒性作用.     

新型转基因植物及其食用安全性评价对策研究进展

随着转基因技术的快速发展,以药用、工业用为代表的新一代转基因植物及复合性状转基因植物不断涌现。与此同时,对其进行食用安全性评价的技术体系却明显滞后。本文主要对药用、工业用及复合性状转基因植物的研究进展进行综述,并对其食用安全评价对策进行阐述和分析,以期为促进我国转基因技术的健康发展提供一定的技术支持。     

南瓜叶浓缩蛋白制品的食用安全性初步评价

采用我国《食品安全性毒理学评价程序》中所规定的标准方法和实验模型,对南瓜叶浓缩蛋白制品的食用安全性进行评价。结果显示,该产品小鼠经口LD50值大于21.501g/kg·bw,属无毒级;小鼠30d喂养未显示任何毒副作用。因此,该产品对实验动物不具有急性毒性作用。      

转基因抗病玉米饲喂Wistar大鼠食用安全性评价

目的:利用不同剂量的转几丁质酶和β-1,3葡聚糖酶基因的转基因抗病玉米粉饲喂Wistar大鼠28d,之后继续用相同剂量未转基因的对照玉米饲喂1w。检测实验期和恢复期Wistar大鼠食用转基因玉米的食用安全性。方法:将Wistar大鼠按体重随机分为1个对照组和饲喂转基因玉米低、中、高剂量组等4个组,每组雌雄各半,经口28d摄入转基因玉米。饲喂期间对大鼠的一般生活状况、体重增长进行观察;大鼠饲喂期和停止饲喂后1w,统计其食物利用率;连续喂饲4w末和停止喂养后1w,对大鼠血清生化学指标进行检查,同时进行解剖学检查。结果:大鼠饲喂转基因玉米后,与对照组比较,一般生活状况无明显差异,无任何中毒症状出现,全部动物健康存活;与对照组同期同性别的大鼠相比,体重增长未见统计学差异(P>0.05);大鼠喂饲4w末和停止喂饲后1w食物利用率未见统计学差异(P>0.05);饲喂转基因玉米期间,大鼠血清谷草转氨酶(AST)/谷丙转氨酶(ALT)、总蛋白(TP)、白蛋白(ALB)、尿素氮(BUN)、天冬氨酸氨基转移酶(AST)等指标与同期对照组比较未见显著差异(P>0.05);大体解剖肉眼观察,各脏器颜色形态未见异常,脏器系数未见异常。结论:实验周期内转几丁质酶和β-1,3葡聚糖酶的转基因抗病玉米对Wistar大鼠生长发育无明显不良影响,转几丁质酶和β-1,3葡聚糖酶的转基因抗病玉米及其亲本玉米对大鼠具有同等的食用安全性。     

来源于转基因植物的食品安全性评价原则和内容

本文介绍了实质等同性等转基因食品安全评价的原则,按国际标准中对来源于重组DNA植物的食品安全评价的框架,从重组DNA植物描述、宿主植物描述、供体生物描述、基因修饰的特征、安全评价、代谢物的评价及需要考虑的其它因素等方面,阐述了对来源于重组DNA植物进行食品安全评价的主要内容。     

转基因水稻食用安全性评价国内外概况

转基因水稻的研制与开发已经达到了可商业化阶段,但是出于对其食用与环境安全性的忧虑,目前还没有国家批准转基因水稻商品化。我国已经发现有疑似转基因稻种出现在市场上,这就迫切要求我们加快对转基因水稻的安全性评价尤其是食用安全性评价的研究,建立相应的评价标准,以规范转基因水稻的商业化及生产。本文主要从转基因水稻的营养成分实质等同性分析,动物营养学评价,体内及体外毒理学评价,致敏性评价及外源基因的水平转移五个角度对转基因水稻的国内外食用安全性评价工作进行了综述,以期为以后的食用安全性评价及标准体系的建立提供参考。     

转基因食品的安全性评价

转基因食品的安全性一直受到各国政府、科学工作者及广大消费者的重视如何科学地评价该类食品的安全性,FAO/WHO等国际组织提出了一些政策性建议本文就转基因食品安全性评价的发展、评价原则、安全性要求、评价方法等作综述     

转基因大米育种及其食用安全性研究进展

伴随着环境的恶化及资源的短缺,世界范围内正面临着一场粮食危机,转基因育种技术也因此得以迅速发展与应用。主要介绍了转基因大米的育种技术,同时对转基因大米的食用安全性进行了论述。     

发酵法L-丙氨酸大鼠90天喂养试验研究

目的研究发酵法L-丙氨酸对大鼠的亚慢性毒性和最大无作用剂量。方法依据《食品安全性毒理学评价程序和方法》进行试验,采用4周龄清洁级健康离乳SD大鼠96只,雌雄各半,随机分为4组,分别给予发酵法L-丙氨酸0.00、1.25、2.50、5.00 g/kg BW掺入基础饲料连续喂饲90 d。第45天眼内眦静脉采血进行血常规检测;第90天采血测定血常规及生化指标,取肝、脾、肾、睾丸、卵巢称重并计算其脏体比,并对大脑、小脑、心、胸腺、肺、肝、肾、肾上腺、脾、胃、十二指肠、睾丸、卵巢、子宫等进行病理学检查。结果各剂量组动物活动、生长正常,末期体重、总进食量、总食物利用率,以及脏器绝对重量、脏体比与对照组相比差异均无统计学意义(P0.05);试验中、末期血常规和血生化指标均未发现有意义的异常改变;病理学检查未见与受试物有关的病理改变。结论发酵法L-丙氨酸对雌、雄大鼠亚慢性毒性试验未观察到有害作用剂量(NOAEL)分别为5.56、4.58 g/kg BW。     

泽泻60天大鼠喂养试验研究

为评价泽泻的安全性 ,采用大鼠 6 0d喂养的方法 ,动物经口灌胃给予泽泻水煎液 ,以研究其亚慢性毒性。结果显示 :泽泻水煎液的低、中、高 3个给药组 (剂量分别为 8 3、16 7和33 3g kgBW,相当于临床用量的 5 0、10 0和 2 0 0倍 )与对照组相比 ,体重和食物利用率组间的差异无显著性 (P >0 0 5 ) ;血尿素氮 (BUN)有升高的趋势 ,高剂量组与对照组相比 ,差异有显著性 (P <0 0 5 ) ,但均未超出正常范围 ;中、高剂量组大鼠尿γ -谷氨转移酶 (γ -GT)活性高于对照组 ,差异有显著性 (P <0 0 5 ) ,血、尿常规及生化指标无与所给受试物相关的异常变化 ;高剂量组大鼠肝 体比值和肾 体比值高于对照组 ,但病理组织学检查结果表明各实验组大鼠肝脏、肾脏、脾和睾丸均无明显的病理性损伤。以上结果表明在本实验条件下 ,泽泻中、高剂量组大鼠尿γ -GT指标有异常改变 ,但病理组织学检查未见明显病理性损伤。     

Kooroo color: 90-day dietary toxicity study in F344 rats

A subchronic toxicity study on kooroo color was conducted using F344 rats of both genders. Kooroo color is an extract of yam root, Dioscorea matudai Hayata, of which the major components are known to be flavonoid pigments. Use of kooroo as a food color is permitted by the Food Sanitation Law in Japan, but the chronic toxicity has not been evaluated in the literature. Rats were fed the product of kooroo color (PKC) at doses of 0.5%, 1.50%, and 5.0% in basal powder diet, while control groups received PKC-free basal diet, for ninety days. A vehicle control given propylene glycol (PG) alone, at the same dosage that the 5.0% group received, was included, because PKC used in this study contained ca. 80 percent PG, used as an extractant during the manufacturing processes. Daily observation of general behavior, and weekly measurement of body weight as well as food consumption were performed. Hematological, serum biochemical and anatomopathological examinations were conducted at the end of administration. No abnormalities ascribable to the treatment with PKC or PG were noted in any examination in this study. Hence, dietary intake of 5.0% of PKC, i.e., 2,993 mg/kg/day for males, and 3,376 mg/kg/day for females, as a mean daily intake for 90 days, had no observable adverse effect in F344 rats. Therefore, kooroo color has no significant general toxicity, and its toxicity, if any, is of a very low order.     

Fukuronori (Gloiopeltis furcata) extract: 90-day dietary toxicity study in F344 rats

Fukuronori extract (FE), which is mainly composed of polysaccharides, and is an extract of the seaweed Gloiopeltis furcata, is permitted for use as a food thickening agent by the Ministry of Health and Welfare, Japan. In order to study the subchronic toxicity of FE, F344 rats of both genders were administered FE at concentrations of 0% (basal diet, control group), 0.5%, 1.5% and 5.0% in basal powder diet for 90 days, and observation of general condition, recording of body weight and food consumption, examination of hematology and blood chemistry, measurement of organ weight, and pathological examination were performed. Food consumption tended to increase in both sexes given FE at 1.5% and 5.0% throughout most of the experimental period. This was, however, considered not to be a toxic effect because the differences in body weight were small. Total cholesterol and triglycerides in serum decreased significantly (p < 0.05) and not significantly, respectively, in males of the 5.0% group. These changes were considered to be related to the intake of FE, but the differences were slight and within physiological ranges. Hematological and pathological examination revealed neither any particular adverse effect nor any significant difference from the control. Hence, dietary intake of 5.0% of FE, 3,362 mg/kg/day for males and 3,594 mg/kg/day for females as mean daily intake, for 90 days was considered to be a no observable adverse effect level in rats.     

Mitigation of methane production from cattle by feeding cashew nut shell liquid

The effects of cashew nut shell liquid (CNSL) feeding on methane production and rumen fermentation were investigated by repeatedly using 3 Holstein nonlactating cows with rumen fistulas. The cows were fed a concentrate and hay diet (6:4 ratio) for 4 wk (control period) followed by the same diet with a CNSL-containing pellet for the next 3 wk (CNSL period). Two trials were conducted using CNSL pellets blended with only silica (trial 1) or with several other ingredients (trial 2). Each pellet type was fed to cows to allow CNSL intake at 4g/100kg of body weight per day. Methane production was measured in a respiration chamber system, and energy balance, nutrient digestibility, and rumen microbial changes were monitored. Methane production per unit of dry matter intake decreased by 38.3 and 19.3% in CNSL feeding trials 1 and 2, respectively. Energy loss as methane emission decreased from 9.7 to 6.1% (trial 1) and from 8.4 to 7.0% (trial 2) with CNSL feeding, whereas the loss to feces (trial 1) and heat production (trial 2) increased. Retained energy did not differ between the control and CNSL periods. Digestibility of dry matter and gross energy decreased with CNSL feeding in trial 1, but did not differ in trial 2. Feeding CNSL caused a decrease in acetate and total short-chain fatty acid levels and an increase in propionate proportion in both trials. Relative copy number of methyl coenzyme-M reductase subunit A gene and its expression decreased with CNSL feeding. The relative abundance of fibrolytic or formate-producing species such as Ruminococcus flavefaciens, Butyrivibrio fibrisolvens, and Treponema bryantii decreased, but species related to propionate production, including Prevotella ruminicolla, Selenomonas ruminantium, Anaerovibrio lipolytica, and Succinivibrio dextrinosolvens, increased. If used in a suitable formulation, CNSL acts as a potent methane-inhibiting and propionate-enhancing agent through the alteration of rumen microbiota without adversely affecting feed digestibility.     

河南省居民肉及肉制品中铜摄入水平及其风险评估

目的以河南省肉及肉制品中铜为例,演示采用简单分布评估方法,评价河南省居民肉及肉制品饮食中铜摄入情况及其潜在的健康风险。方法 2014—2015年在河南省16个省辖市随机采集肉及肉制品309份,按照食品中铜测定的原子吸收光谱法标准操作程序进行检测,结合河南省2010—2012年开展的居民营养与健康状况监测中肉及肉制品的消费量数据,采用简单分布模型(确定性评估)方法,借鉴文献发表的肉及肉制品对膳食中铜的贡献率,计算河南省不同年龄组人群全膳食中铜摄入水平及其潜在的健康风险。结果肉及肉制品中铜的平均含量为0.556 mg/100 g,中位数为0.060 mg/100 g,不同肉及肉制品中铜平均含量最高为内脏(1.561 mg/100 g),铜平均含量最低的为猪肉(0.068 mg/100 g)。河南省居民每天通过进食肉及肉制品的铜平均摄入量为0.046 mg/d,高端(P95)摄入量为0.144 mg/d。利用文献报道的肉及肉制品贡献率外推全膳食中铜摄入量后发现,河南省居民全膳食中铜的平均和P95摄入量分别为0.638和1.977 mg/d。个体评估结果显示,全人群铜摄入量处于推荐摄入量(RNI)与可耐受最高摄入量(UL)之间的个体比例为21.12%(801/3 792),处于EAR和RNI之间的个体比例为8.10%(307/3 792),而低于平均需要量(EAR)、大于UL的人群比例分别为69.75%(2 645/3 792)和1.03%(39/3 792)。结论河南省全人群膳食中铜摄入量缺乏的风险较高,铜过量的风险较低。     

Toxicological evaluation of transgenic rice flour with an Escherichia coli phytase gene appA by sub‐chronic feeding study in Wistar rats

BACKGROUND: Phytase is increasingly used as an ingredient in swine and poultry feeds to improve the bioavailability of phytate‐bound phosphorus and reduce the supplement of elemental phosphorus in feeds. Recently, a transgenic rise (TGR) with phytase appA gene from E. coli has been developed in Taiwan. To assure the food safety of this TGR, we performed a sub‐chronic whole‐food feeding study with Wistar rats. RESULTS: Weaned feeding male and female rats were divided into TGR and non‐TGR (NTGR) groups (20 rats per group), and fed diets containing 76.8% rice flour of TGR and NTGR, respectively. After 93 days feeding, although some hematological findings and blood chemistry values differed significantly between the TGR and NTGR groups, all values were still within the normal range for rats of this age and sex. No adverse effects of TGR were observed in terms of animal behavior, weight gain, or feed utilization rate. Necropsy at the end of the experiment indicated that neither pathological lesions nor histopathological abnormalities were present in organs such as liver, kidney, intestines and testes of rats in TGR and NTGR groups. In addition, no significant differences (P > 0.05) were observed in relative organ weights, hemograms and blood indices of rats between the two groups. CONCLUSION: These results demonstrated that in a 93‐day feeding study with Wistar rats a diet containing 76.8% of TGR flour having a phytase activity of about 1500 U kg^?1 body weight per day has no adverse effects. Copyright © 2007 Society of Chemical Industry     

浅析肉制品中植物源性转基因成分风险

肉制品种类繁多, 是人们日常饮食中重要的组成部分。在现代肉类产品加工过程中, 为改善肉制品的品质、优化产品质量、确保营养均衡, 植物源的成份如植物蛋白、淀粉、膳食纤维、食用胶、植物油以及各种调味品等被广泛运用。伴随着当前全球范围内转基因作物的商品化, 导致肉制品中不可避免地面临植物源性转基因成分风险。本文主要对我国肉制品的现状、肉制品中植物源性成分的使用、肉制品中植物源转基因成分风险以及转基因成分检测进行了概述。旨在引起社会对来自于转基因农作物成分在肉制品下游加工环节中使用情况加以关注, 从而推动转基因食品追溯体系的建立, 进一步规范标识。     

Detection of mechanically recovered meat and head meat from cattle in ground beef mixtures by multivariate analysis of isoelectric focusing protein profiles

The present work investigates the possibility of constructing a multivariate calibration model for predicting the composition of ground beef with respect to different meat quality types, based on intensity profiles from isoelectric focusing of water-soluble proteins. Beef mixtures containing various amounts of mechanically recovered meat, head meat and production meat from beef, were analysed by isoelectric focusing in immobilised pH-gradients. The gels were photographed and the images transferred to a digital format. By simple image processing procedures, background colour was virtually eliminated and signal strength was improved to a considerable degree. Multivariate analysis of protein profiles from the gels gave models explaining 75 to 90% of variance in sample composition. Manually deboned meat was explained to the highest degree, and with a precision of 7%. Two different qualities of mechanically recovered meat could be detected even when treated as one category. The present approach needs further refinement, but seems applicable for detecting intentional substitution of high quality meat products with low-price raw materials. One advantage of the approach is that evaluation of samples is not dependent on specific knowledge on the individual components to be analysed, so that such analytical methods are relatively easy to implement in any standard laboratory.