Search

Omega-3 long-chain polyunsaturated fatty acids (n-3 LC PUFAs) and vitamin D3 are essential components of human nutrition. A regular human diet is highly deficient in n-3 LC PUFAs. Fish like salmon are highly recommended in the human diet as they are a major source of high-value n-3 LC PUFAs and vitamin D3. The levels of these nutrients have been decreasing over the last few years in farmed salmon, whose production urgently needs sustainable sources of these nutrients. The microalga Nannochloropsis gaditana (NG) is known for its naturally high potential for the production of eicosapentaenoic (EPA, 20:5 n-3) fatty acid. A commercial diet for Atlantic salmon was supplemented with 1% and 10% of spray-dried NG grown under controlled conditions for a high EPA content. Salmon were harvested on day 49, following which, boneless and skinless salmon meat was recovered from fish and analyzed for the fatty acid profile, total fat, and vitamin D3. Vitamin D3, EPA, and docosapentaenoic fatty acid (DPA, 22:5 n-3) levels were significantly increased (p < 0.05) by supplementing the basal diet with 10% NG, thus, NG represents a novel, functional, natural ingredient and a sustainable source of n-3 LC-PUFAs that can raise the levels of healthy fats and vitamin D3 in farmed salmon meat.

Consumption of legumes is associated with a number of physiological and health benefits. Legume proteins complement very well those of cereals and are often used to produce gluten-free products. However, legume seeds often contain antinutritional compounds, such as phytate, galactooligosaccharides, phenolic compounds, lectins, enzyme inhibitors, whose presence could affect their nutritional value. Screening natural and induced biodiversity for useful traits, followed by breeding, is a way to remove undesirable components. We used the common bean cv. Lady Joy and the lpa1 mutant line, having different seed composition for absence/presence of lectins,α-amylase inhibitor, (α-AI) and phytic acid, to verify the advantage of their use to make biscuits with improved nutritional properties. We showed that use of unprocessed flour from normal beans (Taylor's Horticulture and Billo) must be avoided, since lectin activity is still present after baking, and demonstrated the advantage of using the cv. Lady Joy, lacking active lectins and having active α-AI. To assess the contribution of bean flour to biscuit quality traits, different formulations of composite flours (B12, B14, B22, B24, B29) were used in combinations with wheat (B14), maize (gluten-free B22 and B29), or with both (B12 and B24). These biscuits were nutritionally better than the control, having a better amino acid score, higher fiber amount, lower predicted glycemic index (pGI) and starch content. Replacement of cv. Lady Joy bean flour with that of lpa1, having a 90% reduction of phytic acid and devoid of α-AI, contributed to about a 50% reduction of phytic acid content. We also showed that baking did not fully inactivate α-AI, further contributing to lowering the pGI of the biscuits. Finally, data from a blind taste test using consumers indicated that the B14 biscuit was accepted by consumers and comparable in terms of liking to the control biscuit, although the acceptability of these products decreased with the increase of bean content. The B22 gluten-free biscuits, although received liking scores that were just above the middle point of the hedonic scale, might represent a good compromise between health benefits (absence of gluten and lower pGI), expectations of celiac consumers and likeness.

Wheat, like many other staple cereals, contains low levels of the essential micronutrients iron and zinc. Up to two billion people worldwide suffer from iron and zinc deficiencies, particularly in regions with predominantly cereal-based diets. Although wheat flour is commonly fortified during processing, an attractive and more sustainable solution is biofortification, which requires developing new varieties of wheat with inherently higher iron and zinc content in their grains. Until now most studies aimed at increasing iron and zinc content in wheat grains have focused on discovering natural variation in progenitor or related species. However, recent developments in genomics and transformation have led to a step change in targeted research on wheat at a molecular level. We discuss promising approaches to improve iron and zinc content in wheat using knowledge gained in model grasses. We explore how the latest resources developed in wheat, including sequenced genomes and mutant populations, can be exploited for biofortification. We also highlight the key research and practical challenges that remain in improving iron and zinc content in wheat.

An iterative approach to optimising the accumulation of non-native long chain polyunsaturated fatty acids in transgenic plants was undertaken in Arabidopsis thaliana. The contribution of a number of different transgene enzyme activities was systematically determined, as was the contribution of endogenous fatty acid metabolism. Successive iterations were informed by lipidomic analysis of neutral, polar and acyl-CoA pools. This approach allowed for a four-fold improvement on levels previously reported for the accumulation of eicosapentaenoic acid in Arabidopsis seeds and also facilitated the successful engineering of the high value polyunsaturated fatty acid docosahexaenoic acid to 10-fold higher levels. Our studies identify the minimal gene set required to direct the efficient synthesis of these fatty acids in transgenic seed oil., Highlights ► Successful iteration of EPA and DHA accumulation in transgenic plants. ► Systematic identification of optimal genes for accumulation of DHA. ► Demonstration of the utility of lipidomic-driven plant metabolic engineering.

Numerous crops have been bred or engineered to increase carotenoid levels in an effort to develop novel strategies that address vitamin A deficiency in the developing world. The pioneering work in rice (not covered in this review) has been followed up in many additional crops, some of which are staples like rice whereas others are luxury products whose impact on food security is likely to be marginal. This review surveys the progress that has been made in carotenoid breeding and metabolic engineering, focusing on β-carotene enhancement in crops other than rice. We ask if these efforts have the potential to address vitamin A deficiency in developing countries by comparing bioavailable pro-vitamin A levels in wild type and enhanced crops to determine whether nutritional requirements can be met without the consumption of unrealistic amounts of food. The potential impact of carotenoid enhancement should therefore be judged against benchmarks that include the importance of particular crops in terms of global food security, the amount of bioavailable β-carotene, and the amount of food that must be consumed to achieve the reference daily intake of vitamin A. Research in our laboratory is supported by the Ministry of Science and Innovation (MICINN) Grant BFU2007- 61413; European Research Council Advanced Grant BIOFORCE; Center Consolider, MICINN, Spain; COST Action FA0804, Associated Unit CAVA; and the SmartCell, FP7 Integrated Project.