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1.
The genetic modification in fruit and vegetables could lead to changes in metabolic pathways and, therefore, to the variation of the molecular pattern, with particular attention to antioxidant compounds not well-described in the literature. The aim of the present study was to compare the quality composition of transgenic wheat ( Triticum durum L.), corn ( Zea mays L.), and tomato ( Lycopersicum esculentum Mill.) to the nontransgenic control with a similar genetic background. In the first experiment, Ofanto wheat cultivar containing the tobacco rab1 gene and nontransgenic Ofanto were used. The second experiment compared two transgenic lines of corn containing Bacillus thuringiensis "Cry toxin" gene (PR33P67 and Pegaso Bt) to their nontransgenic forms. The third experiment was conducted on transgenic tomato ( Lycopersicum esculentum Mill.) containing the Agrobacterium rhizogenes rolD gene and its nontransgenic control (cv. Tondino). Conventional and genetically modified crops were compared in terms of fatty acids content, unsaponifiable fraction of antioxidants, total phenols, polyphenols, carotenoids, vitamin C, total antioxidant activity, and mineral composition. No significant differences were observed for qualitative traits analyzed in wheat and corn samples. In tomato samples, the total antioxidant activity (TAA), measured by FRAP assay, and the naringenin content showed a lower value in genetically modified organism (GMO) samples (0.35 mmol of Fe (2+) 100 g (-1) and 2.82 mg 100 g (-1), respectively), in comparison to its nontransgenic control (0.41 mmol of Fe (2+) 100 g (-1) and 4.17 mg 100 g (-1), respectively). On the basis of the principle of substantial equivalence, as articulated by the World Health Organization, the Organization for Economic Cooperation and Development, and the United Nations Food and Agriculture Organization, these data support the conclusion that GM events are nutritionally similar to conventional varieties of wheat, corn, and tomato on the market today.  相似文献   

2.
Insect-protected corn hybrids containing event MON 863 protect corn plants against feeding damage from corn rootworm (Diabrotica), a major North American insect pest. Corn event MON 863 contains a gene that expresses an amino acid sequence variant of the wild-type Cry3Bb1 insecticidal protein from Bacillus thuringiensis. The purpose of this study was to compare the composition of corn containing event MON 863 with that of conventional nontransgenic corn. Compositional analyses were conducted to measure proximates, fiber, amino acids, fatty acids, minerals, folic acid, thiamin, riboflavin, vitamin E, antinutrients, and certain secondary metabolites in grain and proximates and fiber content in forage collected from a total of eight field sites in the U.S. and Argentina. Compositional analyses demonstrated that the grain and forage of event MON 863 are comparable in their nutritional content to the control corn hybrid and conventional corn. These comparisons, together with the history of the safe use of corn as a common component of animal feed and human food, support the conclusion that corn event MON 863 is compositionally equivalent to, and as safe and nutritious as, conventional corn hybrids grown commercially today.  相似文献   

3.
Prospective testing for allergenicity of proteins obtained from sources with no prior history of causing allergy has been difficult to perform. Thus, the objective of this work was to assess the food safety of genetically modified maize with an amaranth globulin protein termed amarantin. Transgenic maize lines evaluated showed, in relation to nontransgenic, 4-35% more protein and 0-44% higher contents of specific essential amino acids. Individual sequence analysis with known amino acid sequences, reported as allergens, showed that none of these IgE elicitors were identified in amarantin. Amarantin was digested within the first 15 min by Simulated Gastric Fluid treatment as observed by Western blot. Expressed amarantin did not induce important levels of specific IgE antibodies in BALB/c mice, as analyzed by ELISA. We conclude that the transgenic maize with amarantin is not an important allergenicity inducer, just as nontransgenic maize.  相似文献   

4.
The aim was to determine the fate of transgenic and endogenous plant DNA fragments in the blood, tissues, and digesta of broilers. Male broiler chicks (n = 24) were allocated at 1 day old to each of four treatment diets designated T1-T4. T1 and T2 contained the near isogenic nongenetically modified (GM) maize grain, whereas T3 and T4 contained GM maize grain [cry1a(b) gene]; T1 and T3 also contained the near isogenic non-GM soybean meal, whereas T2 and T4 contained GM soybean meal (cp4epsps gene). Four days prior to slaughter at 39-42 days old, 50% of the broilers on T2-T4 had the source(s) of GM ingredients replaced by their non-GM counterparts. Detection of specific DNA sequences in feed, tissue, and digesta samples was completed by polymerase chain reaction analysis. Seven primer pairs were used to amplify fragments ( approximately 200 bp) from single copy genes (maize high mobility protein, soya lectin, and transgenes in the GM feeds) and multicopy genes (poultry mitochondrial cytochrome b, maize, and soya rubisco). There was no effect of treatment on the measured growth performance parameters. Except for a single detection of lectin (nontransgenic single copy gene; unsubstantiated) in the extracted DNA from one bursa tissue sample, there was no positive detection of any endogenous or transgenic single copy genes in either blood or tissue DNA samples. However, the multicopy rubisco gene was detected in a proportion of samples from all tissue types (23% of total across all tissues studied) and in low numbers in blood. Feed-derived DNA was found to survive complete degradation up to the large intestine. Transgenic DNA was detected in gizzard digesta but not in intestinal digesta 96 h after the last feeding of treatment diets containing a source of GM maize and/or soybean meal.  相似文献   

5.
Cotton plants were genetically modified through the introduction of a synthetic gene that encodes a Bacillus thuringiensis insecticidal protoxin referred to as Cry1F(synpro). This protoxin is a chimeric, full-length delta-endotoxin of 130 kDa, comprised of the core toxin of Cry1Fa2 protein and parts of the nontoxic portions of Cry1Ca3 and Cry1Ab1 proteins, all of which originated from Bacillus thuringiensis. The Cry1F(synpro) expressed in cotton plants confers resistance to lepidopteran pests. The current study was conducted to characterize the Cry1F(synpro) protein expressed in the transgenic cotton event 281-24-236. Results showed that the full-length Cry1F(synpro) produced in the transgenic cotton plants was sensitive to the host cell protease cleavage, resulting in a truncated, biologically active form (core toxin) with an apparent molecular mass of 65 kDa. This truncated toxin was purified by immunoaffinity chromatography from the cotton leaf extract. N-terminal sequencing, peptide mass fingerprinting by MALDI-TOF MS, and internal peptide sequencing by MS/MS confirmed the identity of the truncated core toxin of Cry1F. The mechanism of truncation was explored with Cry1F(synpro) derived from a recombinant Pseudomonas fluorescens. The transgenic cotton-produced Cry1F showed equivalent insecticidal activity to that of Pseudomonas fluorescens-derived Cry1F.  相似文献   

6.
The objective of the study was to track the fate of recombinant Cry1Ab protein in a liquid manure field trial when feeding GM maize MON810 to dairy cows. A validated ELISA was applied for quantification of Cry1Ab in the agricultural chain from GM maize plants, feed, liquid manure and soil to crops grown on manured fields. Starting with 23.7 μg of Cry1Ab g(-1) dry weight GM maize material, a rapid decline of Cry1Ab levels was observed as 2.6% and 0.9% of Cry1Ab from the GM plant were detected in feed and liquid manure, respectively. Half of this residual Cry1Ab persisted during slurry storage for 25 weeks. After application to experimental fields, final degradation of Cry1Ab to below detectable levels in soil was reported. Cry1Ab exhibited a higher rate of degradation compared to total protein in the agricultural processes. Immunoblotting revealed a degradation of the 65 kDa Cry1Ab into immunoreactive fragments of lower size in all analyzed materials.  相似文献   

7.
Insect-protected corn hybrids containing Cry insecticidal proteins derived from Bacillus thuringiensis have protection from target pests and provide effective management of insect resistance. MON 89034 hybrids have been developed that produce both the Cry1A.105 and Cry2Ab2 proteins, which provide two independent modes of insecticidal action against the European corn borer ( Ostrinia nubilalis ) and other lepidopteran insect pests of corn. The composition of MON 89034 corn was compared to conventional corn by measuring proximates, fiber, and minerals in forage and by measuring proximates, fiber, amino acids, fatty acids, vitamins, minerals, antinutrients, and secondary metabolites in grain collected from 10 replicated field sites across the United States and Argentina during the 2004-2005 growing seasons. Analyses established that the forage and grain from MON 89034 are compositionally comparable to the control corn hybrid and conventional corn reference hybrids. These findings support the conclusion that MON 89034 is compositionally equivalent to conventional corn hybrids.  相似文献   

8.
The persistence of Cry1Ac protein in the soil and its effect on soil microbial communities are a core issue in assessing the ecological risk of transgenic Bacillus thuringiensis (Bt) cotton. In this study a field experiment was conducted on the cultivation of transgenic Bt cotton (Jin 26 and BtJi 668) with the immediate returning of residues to the fields, in order to quantify the Cry1Ac protein content in the fields and investigate its effects on the functional diversity of soil microbial communities. Cry1Ac protein in the residue-soil mixture was gradually degraded in the transgenic Bt cotton fields. After transgenic Bt cotton straw was returned to the fields for 30 d, 63.73% and 58.33% of the initial amounts of Cry1Ac protein were degraded in the Jin 26 and BtJi 668 fields, respectively. Before the crops were sown in the following year (180 d after returning the straw), no Cry1Ac protein was detected in the fields. After returning the cotton straw to the fields for 30 d, the Shannon-Wiener and McIntosh indices of soil microbial communities in the transgenic Bt cotton fields were significantly higher than those in the non-transgenic cotton fields. Meanwhile, the utilization of carbon sources including amino acids, amines, and carbohydrates by the soil microbial communities significantly increased. Both the McIntosh index and the utilization of carbohydrates increased until 180 d. Principal component analysis revealed that amino acids, amides, and carbohydrates were the main carbon sources distinguishing the two principal component factors. These findings indicated that Cry1Ac protein did not accumulate in the fields after transgenic Bt cotton was planted for one year and the residues were immediately returned to the fields; however, the original functional diversity of soil microbial communities was affected continuously.  相似文献   

9.
Cry34Ab1 and Cry35Ab1 proteins, identified from Bacillus thuringiensis strain PS149B1, act together to control corn rootworms. Transgenic corn lines coexpressing the two proteins were developed to protect corn against rootworm damage. Large quantities of the two proteins were needed to conduct studies required for assessing the safety of this transgenic corn crop. Because it was technically infeasible to obtain sufficient quantities of high purity Cry34Ab1 and Cry35Ab1 proteins from the transgenic corn plants, the proteins were produced using a recombinant Pseudomonas fluorescens (Pf) production system. The two proteins from both the transgenic corn and the Pf were purified and characterized. The proteins from each host had the expected molecular mass and were immunoreactive to specific antibodies in enzyme-linked immunosorbent assay and Western blot analysis. Data from N-terminal sequencing, tryptic peptide mass fingerprinting, internal peptide sequencing, and biological activity provided direct evidence that the Cry34Ab1 and Cry35Ab1 proteins produced in Pf and transgenic corn were, respectively, comparable or equivalent molecules. In addition, neither protein had detectable glycosylation regardless of the host.  相似文献   

10.
A stilbene synthase gene along with the selectable marker gene bar for herbicide resistance was transferred via Agrobacterium tumefaciens mediated transformation into apple (Malus domesticaBorkh.) cvs. 'Elstar' and 'Holsteiner Cox'. The stilbene synthase catalyzes the conversion of 1 molecule of p-coumaroyl-CoA and 3 molecules of malonyl-CoA into 3,4',5-trihydroxystilbene, commonly known as resveratrol. This phytoalexin has implications in both phytopathology and human health. Greenhouse-grown transgenic and nontransformed control plants were grafted onto dwarfing rootstock M27. Flowering and fruiting occurred within the following years, offering the opportunity to analyze transgenic apple fruit and fertility of transgenic plants as well as inheritance of the transgenes into the seedling progeny. Molecular analysis revealed that the stilbene synthase is expressed in transgenic plants and in the skin and flesh of transgenic apple fruit. After formation, resveratrol is modified by the addition of a hexose sugar. The resulting component was characterized as piceid. With the aim of characterizing the influence of the novel biosynthetic pathway on the accumulation of other phenolic compounds naturally present in apple fruit, the amounts of flavanols, flavonols, phloretin derivatives and hydroxycinnamic acids in wild type and transgenic fruit were determined by HPLC. In all investigated transformed lines that accumulated piceid, no negative correlation between levels of piceid and the above-mentioned compounds was observed, except for the flavonol contents, which slightly decreased. Inheritance of the transgenes was confirmed in the seedling progeny, which were obtained after pollination of transgenic plants with nontransgenic pollen and vice versa after pollination of nontransgenic plants with pollen obtained from transgenic plants. The fertility of stilbene synthase transgenic plants was demonstrated. To the authors' knowledge this is the first time that data are available on piceid synthesis in transgenic apple fruit and the effects of its accumulation on levels of other phenolic compounds present in the fruit.  相似文献   

11.
Understanding the impact of genetic diversity on crop biochemical composition is a prerequisite to the interpretation and potential relevance of biochemical differences experimentally observed between genotypes. This is particularly important in the context of comparative safety assessments for crops developed by new technologies such as genetic engineering. To interrogate the natural variability of biochemical composition, grain from seven maize hybrids grown at four geographically distinct sites in Europe was analyzed for levels of proximates (fat, protein, moisture, ash, and carbohydrates), fiber, amino acids, fatty acids, four vitamins, nine minerals, and secondary metabolites. Statistical evaluation of the compositional data at the p < 0.05 level compared each hybrid against every other hybrid (head-to-head) for all analytes at each site and then across all sites to understand the factors contributing to variability. Of the 4935 statistical comparisons made in this study, 40% (1986) were found to be significant. The magnitude of differences observed, as a percent, ranged between 0.84 and 149% when all individual sites and the combined sites were considered. The large number of statistically significant differences in the levels of these analytes between seven commercial hybrids emphasizes the importance of genetic background and environment as determinants of the biochemical composition of maize grain, reflects the inherent natural variability in those analytes across a representative sampling of maize hybrids, and provides a baseline of the natural range of these nutritional and antinutritional components in maize for comparative compositional assessments.  相似文献   

12.
The composition of glyphosate-tolerant (Roundup Ready) corn event NK603 was compared with that of conventional corn grown in the United States in 1998 and in the European Union in 1999 to assess compositional equivalence. Grain and forage samples were collected from both replicated and nonreplicated field trials, and compositional analyses were performed to measure proximates, fiber, amino acids, fatty acids, vitamin E, nine minerals, phytic acid, trypsin inhibitor, and secondary metabolites in grain as well as proximates and fiber in forage. Statistical analysis of the data was conducted to assess statistical significance at the p < 0.05 level. The values for all of the biochemical components assessed for corn event NK603 were similar to those of the nontransgenic control or were within the published range observed for nontransgenic commercial corn hybrids. In addition, the compositional profile of Roundup Ready corn event NK603 was compared with that of traditional corn hybrids grown in Europe by calculating a 99% tolerance interval to describe compositional variability in the population of traditional corn varieties in the marketplace. These comparisons, together with the history of the safe use of corn as a common component of animal feed and human food, support the conclusion that Roundup Ready corn event NK603 is compositionally equivalent to, and as safe and nutritious as, conventional corn hybrids grown commercially today.  相似文献   

13.
γ-Linolenic acid (GLA) has been used as a general nutraceutical for pharmacologic applications, particularly in the treatment of skin conditions such as eczema. Four transgenic soybean lines that produce GLA at high yields (4.21% of total fatty acids, up to 1002-fold) were generated through the stable insertion of the Delta-6-fatty acid desaturase gene isolated from Borago officinalis into the genome of a conventional soybean cultivar. As part of the safety assessment of genetically engineered crops, the transgenic soybean seeds were compared with their parental soybean seeds (nontransgenic) by applying the principle of substantial equivalence. Compositional analyses were conducted by measuring the fatty acids, proximate analysis (moisture, crude protein, crude fat, carbohydrates, TDF, and ash contents), amino acids, lectins, and trypsin inhibitor activity. The present results showed that the specific transgenic cultivar studied was similar to the conventional control.  相似文献   

14.
对转cry1Ab基因抗虫水稻矮秆突变体的品质性状与原亲本秀水11进行了对比分析,发现在最高粘度、热浆粘度和冷胶粘度等RVA谱特征值上两者有显著差异,而在外观品质、碾磨品质、表观直链淀粉含量、胶稠度和淀粉粘滞特性的崩解值、消减值等淀粉食用品质方面基本相同,在蛋白、脂肪、灰分、矿物质和氨基酸等关键营养成分上也不存在显著差异,在蒸煮后的矮杆突变体米粒中也未检测到Cry1Ab杀虫蛋白。  相似文献   

15.
Understanding natural variation in the composition of conventional crop germplasms is critical in establishing a baseline for comparison of biotechnology-derived crops. This is particularly relevant to such traits as tolerance to drought stress. Thus, there is both a need to understand the contribution of stress conditions to natural variation in plant nutritional components and to determine whether levels of small molecule metabolites such as osmoprotectants and stress metabolites are also affected. As a first step in developing such information for maize, seven conventional hybrids were grown under different moisture regimens and the impact of moisture on composition was assessed. The regimens included well-watered conditions, water restriction during the vegetative phase, and water restriction during grain fill. Compositional analyses of the harvested grain included assessments of the levels of proximates (moisture, protein, oil, starch) and small molecule metabolites such as fatty acids, free amino acids, organic acids, sugars, total glycerol, glycine betaine, and abscisic acid. Ranges for these analytes were determined across all moisture regimens, and the effect of the different water regimens on these analytes was also evaluated. The number and type of grain analytes that showed statistically significant differences in levels between different water regimens differed quite markedly by maize hybrid. However, the magnitude of mean differences between well-watered and water-restricted samples was typically small, and statistically significant differences for any given analyte were typically observed in only one to three of the seven maize hybrids. Only two analytes, free glutamine and free proline, showed a significant drought-induced difference in at least four maize hybrids.  相似文献   

16.
Adsorption on a soil matrix of the insecticidal protein from Bacillus thuringiensis ( Bt) transgenic plants affects their accumulation and release and, hence, bioavailability in soil. Cry1Ab protein isolated from Bt transgenic rice was used to evaluate the adsorption and desorption on bentone, kaolin, and humic acids (HAs). The adsorption equilibrium of Cry1Ab protein was reached within 1-2 h for bentone and kaolin and within 4-8 h for HAs. The adsorption isotherms were better described by linear expressions ( R (2) >/= 0.973) rather than by the Freundlich model. No saturation was observed, even at the maximum concentration used (3.71 microg mL (-1)). The adsorbed protein was not easily desorbed at the used protein concentrations (0.18-3.71 microg mL (-1)); more than 50-70%, 70-80%, and 90% of the adsorbed protein remained on HAs, kaolin, and bentone, respectively, after washing with water. Adsorption and desorption of the Cry1Ab protein were further studied using five soils, and the isotherms were also well-described by linear equations ( p < 0.05). Adsorption of the Cry1Ab protein on soils was positively related to the soil organic matter content.  相似文献   

17.
Transgenic rice TT51-1 (BT63) is an insect resistant strain that was granted for safety certificate in China in 2009. This study characterizes the transgenic event TT51-1 using a GenomeWalker strategy. The organization of the transgenes indicated that the transgenes on two plasmids, pFHBT1 and pGL2RC7, had been integrated at the same locus. The sequence of the event TT51-1 spanned 8725 bp, including a truncated Cry1Ab/Ac cassette, an intact Cry1Ab/Ac cassette, two Amp gene segments, and an Hph gene segment. The 5' and 3' plant flanking sequences were isolated and used to locate the transgenes to chromosome 10 in TT51-1. The isolated TT51-1 fragment and a fragment of the rice PLD gene were integrated into a plasmid vector, to create plasmid pK-TT51 as a calibrator for detecting rice containing TT51-1. Analysis of unknown samples indicated that the reference plasmid was a reliable alternative to TT51-1 genomic DNA.  相似文献   

18.
Protein-based detection methods, enzyme-linked immunosorbent assay (ELISA) and lateral flow strip, have been widely used for rapid, spot, and sensitive detection of genetically modified organisms (GMOs). Herein, one novel quantum dot-based fluorescence-linked immunosorbent assay (QD-FLISA) was developed employing quantum dots (QDs) as the fluorescent marker for the detection of the Cry1Ab protein in MON810 maize. The end-point fluorescent detection system was carried out using QDs conjugated with goat anti-rabbit secondary antibody. The newly developed Cry1Ab QD-FLISA assay was highly specific to the Cry1Ab protein and had no cross-reactivity with other target proteins, such as Cry2Ab, Cry1F, and Cry3Bb. The quantified linearity was achieved in the value range of 0.05-5% (w/w). The limits of detection (LOD) and quantification (LOQ) of the QD-FLISA were 2.956 and 9.854 pg/mL, respectively, which were more sensitive than the conventional sandwich ELISA method. All of the results indicated that QD-FLISA was a highly specific and sensitive method for the monitoring of Cry1Ab in GMOs.  相似文献   

19.
Use of transgenic crops, including those expressing the insecticidal Cry protein from Bt, is increasing at a rapid rate in worldwide. Field and laboratory studies of transgenic Bt crops have been carried out to detect the persistence and activity of the Cry protein in soil and its effect on soil microorganisms to assess their risks to environment. However, there were few studies that evaluate the seasonal effects of Bt rice on rhizosphere soil microbial communities compared to those of insecticides commonly applied in paddy soil for the control of lepidopteran insects. In this study, seasonal effects of transgenic rice expressing the Cry1Ab insecticidal protein active against lepidoperan pests and the insecticide triazophos [3-(o,o-diethyl)-1-phenyl thiophosphoryl-1,2,4-triazol] on soil enzyme activities and microbial communities were compared under field conditions. During a 2-year field study, rhizosphere soil samples of transgenic-Bt rice (Bt), non-Bt parental rice (Ck) and non-Bt parental rice with triazophos (Ckp) applied were taken at four stages in the rice developmental cycle: seedling, booting, heading and maturing. Microbial processes were investigated by measuring different biochemical activities including those involved in C and P cycling. Denaturing gradient gel electrophoresis (DGGE) and terminal-restriction fragment length polymorphism (T-RFLP) analyses were used to compare rhizosphere microbial compositions. Some occasional and inconsistent effects of the application of triazophos on the bacterial composition in the rhizosphere soil of rice plant were found at the booting and heading stages as compared with that of transgenic-Bt rice. There were no statistically significant differences (P>0.05) in phosphatase activity, dehydrogenase activity, respiration, methanogenesis or fungal community composition in rhizosphere soil between Bt, Ck and Ckp over the rice cropping cycle. However, seasonal variations in the selected enzyme activities and microbial community composition in the rhizosphere soil of Bt, Ck and Ckp were clearly detected. These results suggested that the changes in rhizophere soil microbial community composition associated with the crop growth stage overweighed the application of triazophos and the cry1Ab gene transformation. KMD1 (Bt) rice expressing the cry1Ab gene had no measurable adverse effect on the key microbial processes or microbial community composition in rhizophere soil over 2 years of rice cropping.  相似文献   

20.
Earthworms, which play a key role in biogeochemical processes in soil ecosystems, could be negatively affected by the cultivation of transgenic Bt crops. Studies to date have found few effects of Bt maize on earthworm species. If adverse effects occur, they are likely to be chronic or sub-lethal and expressed over large spatial and temporal scales. Our objective in the present study was to investigate potential effects on earthworm populations in soil cultivated with Bt maize in a large multiple-year field study. We surveyed the earthworm populations in 0.16-ha experimental field plots of two varieties of Cry1Ab Bt maize, one variety of Cry3Bb1 Bt maize, and three non-transgenic control varieties cultivated for four years. Four earthworm species were found in our sample: Aporrectodea caliginosa, Aporrectodea trapezoides, Aporrectodea tuberculata (collectively, the A. caliginosa species complex), and Lumbricus terrestris. We found no significant differences in the biomass of juveniles and adults for all four species between Bt and non-Bt maize varieties. From this and previous studies, we conclude that the effects of Cry1Ab and Cry3Bb1 Bt maize on the A. caliginosa species complex and L. terrestris are small. Nonetheless, general conclusions about the effects of Bt maize on earthworm populations are not warranted due to the small number of species tested. In future laboratory studies, earthworm species should be selected according to their association with a Bt crop and the impact of that species to valued soil ecosystem processes.  相似文献   

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