Canola transgenic

The food technologist may be especially interested in the fate of the carotenoids in the seed oil. Like red palm oil, the resulting carotenoid-pigmented canola oil may be more stable due to the antioxidant properties of carotenoids and may be more attractive to consumers. Alternatively, for food security concerns, transgenic soybean or canola oils and seed meals that are genetically modified for more efficient bio-diesel production may be bio-safety marked with lipid-soluble carotenoids and water-soluble anthocyanins, respectively. Potatoes are excellent potential sources of dietary carotenoids, and over-expression of CrtB in tubers led to the accumulation of P-carotene. Potatoes normally have low levels of leaf-type carotenoids, like canola cotyledons. 

Glufosinate has a broad weed spectrum (little to no selectivity), and is therefore sometimes marketed along with genetically engineered glufosinate-resistant crops (cotton, canola, maize, and rice). While this raises some concern in some parts of the world, transgenic technology has been widely accepted in the western hemisphere. Nevertheless, neither... 

Altenbach, S.B., Kuo, C.C., Staraci, L.C. et al. 1992. Accumulation of a Brazil nut albumin in seeds of transgenic canola results in enhanced levels of seed protein methionine. Plant Mol Biol 18 235-245. 

Nie, L., Shah, S., Rashid, A., Burd, G.I., Dixon, D.G., andGlick, B.R. 2002. Phytoremediation of arsenate contaminated soil by transgenic canola and the plant growth-promoting bacterium Enterobacter cloacae CAL2. Plant Physiology and Biochemistry, 40(4) 355-61. 

In a similar fashion, the EIQ has been applied to Canadian canola cultivation in order to estimate the environmental impact of the adoption of herbicide tolerant canola, which includes transgenic varieties. In recent years, herbicide tolerant canola varieties (glyphosate-, glufosinate-, and imidazolinone-tolerant) have been adopted by Canadian fanners at a larges scale, accounting for 80% of the national canola acreage in 2000. The adoption of these herbicide tolerant varieties has been associated with a concomitant decrease in herbicide use on canola. The environmental impact of herbicide use on canola determined by the EIQ method decreased in correlation with the decreased amounts of herbicide applied to the crops, rather than this would be due to different intrinsic properties (EIQ) of the herbicides involved [23]. 

Wang, Y., Nowak, G., Gulley, D., Hadwiger, L.A. and Fristensky B. (1999) Constitutive expression of pea defense gene DRR206 confers resistance to blackleg Leptosphaeria maculans) disease in transgenic canola (Brassica napus). Mol. Plant Microbe Interact., 12, 410-8. 

Ecological concern exists about transmission of pollen from some types of plant, such as the Brassicas and tree crops, either into weedy relatives or into crops grown at some distance. This problem is not limited to transgenic plants. Canola, a rape-seed cultivar bred to produce low glucosinolates and low erucic acid, must be planted in isolation from industrial rapeseed, as each crop will result in seed with altered composition from the ideal that is, excessive erucic acid in the canola and less erucic acid in the industrial rapeseed. Because the products of industrial crops are not intended for consumption, and may even be noxious, risk management and containment, including the prevention of intercrop cross-pollination, is... 

In the study of complex solid and semi-solid foods, solid-state NMR becomes of valuable use. 13C CPMAS NMR has been used to characterize the insoluble deposits in aromatic bitters.275 MAS has been successfully used to characterize and quantify the oil fraction present in intact seeds, and several publications have focused on this subject, e.g. to compare the oil composition of hybrid and transgenic canola seeds.276 In addition, the HR-MAS method has become an important new tool for the study of semi-solids such as flour doughs or intact fruits, as described in section 6.3. 

Fig. 11. Genetic engineering of rapeseed oil. A high level of lauric acid was achieved by expressing a medium-chain acyl-ACP thioesterase (MCTE) from California Bay in the transgenic seeds. This enzyme intercepts the fatty acid synthesis pathway at 12 carbons and hydrolyzes the fatty acid from its ACP carrier. MoI% of major fatty acids in a typical canola cultivar are compared to the composition achieved through genetic engineering.

February 2002 however, Bayer CropScience, the OXY 235 transgene patent holder at that time, decided to withdraw bromoxynil-tolerant double-low rapeseed (canola) and rapeseed from the Canadian market in April 2002. As a consequence, bromoxynil-tolerant HEAR cultivars were not commercialized in Canada. 

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