Search Results (4)

Omega-3 long-chain (≥C₂₀) polyunsaturated fatty acids (ω3 LC-PUFA) play a critical physiological role in health and are nutritionally important for both humans and animals. The abundance of marine-derived resources of the health-benefitting ω3 LC-PUFA is either static or in some cases declining. This review focuses on the development and deregulation of novel oilseed crops producing ω3 LC-PUFA and their market applications. Genetic engineering of ω3 LC-PUFA into sustainable oilseed crops involving multiple-gene pathways to reach fish oil-like levels of these key nutrients has been extremely challenging. After two decades of collaborative effort, oilseed crops containing fish oil-levels of ω3 LC-PUFA and importantly also containing a high ω3/ω6 ratio have been developed. Deregulation of genetically engineered crops with such novel nutritional traits is also challenging and more trait-based regulations should be adopted. Some ω3 LC-PUFA-producing oilseed crops have been approved for large-scale cultivation, and for applications into feed and food. These genetically engineered oilseed crops can and will help meet the increasing market demand for aquaculture and human nutrition. These new oil seed sources of ω3 LC-PUFA offer a sustainable, safe, cost-effective, and scalable land-based solution, which can have critical and positive health, economic, and environmental impacts. Full article

In contrast to ultra-processed foods that are associated with increased weight gain and obesity risk, nutritionally engineered dietary supplements, including meal replacement (MR) bars and shakes, are generally promoted as healthy. Limited data is available comparing the metabolic and hunger responses of whole food (WF) versus MR meals. The purpose of this study was to directly compare the thermic effect (TEM), respiratory exchange ratio (RER), hunger/taste ratings, and glucose response of two different breakfast meals containing MR and WF products in young healthy women. Eight volunteers completed two iso-caloric (529 kcals)/macronutrient (50% carbohydrates; 26% fat; 24% protein) test meals in a single-blind, randomized crossover design: (1) whole food meal; or (2) meal replacement. TEM was significantly higher following MR compared with WF (percent mean difference: 7.76 ± 3.78%; absolute mean difference: 0.053 ± 0.026 kcal/minute, p = 0.048), whereas WF substrate utilization demonstrated lower carbohydrate oxidation (RER) than MR (mean difference: −0.024 ± 0.008, p = 0.005). No differences existed for blood glucose response and feelings of hunger, desire to eat, and satiety among trials. Consumption of an MR meal increases postprandial thermogenesis and RER compared to a WF meal, which may impact weight control and obesity risk over the long-term. Full article

The low phytic acid (lpa), or “low-phytate” seed trait can provide numerous potential benefits to the nutritional quality of foods and feeds and to the sustainability of agricultural production. Major benefits include enhanced phosphorus (P) management contributing to enhanced sustainability in non-ruminant (poultry, swine, and fish) production; reduced environmental impact due to reduced waste P in non-ruminant production; enhanced “global” bioavailability of minerals (iron, zinc, calcium, magnesium) for both humans and non-ruminant animals; enhancement of animal health, productivity and the quality of animal products; development of “low seed total P” crops which also can enhance management of P in agricultural production and contribute to its sustainability. Evaluations of this trait by industry and by advocates of biofortification via breeding for enhanced mineral density have been too short term and too narrowly focused. Arguments against breeding for the low-phytate trait overstate the negatives such as potentially reduced yields and field performance or possible reductions in phytic acid’s health benefits. Progress in breeding or genetically-engineering high-yielding stress-tolerant low-phytate crops continues. Perhaps due to the potential benefits of the low-phytate trait, the challenge of developing high-yielding, stress-tolerant low-phytate crops has become something of a holy grail for crop genetic engineering. While there are widely available and efficacious alternative approaches to deal with the problems posed by seed-derived dietary phytic acid, such as use of the enzyme phytase as a feed additive, or biofortification breeding, if there were an interest in developing low-phytate crops with good field performance and good seed quality, it could be accomplished given adequate time and support. Even with a moderate reduction in yield, in light of the numerous benefits of low-phytate types as human foods or animal feeds, should one not grow a nutritionally-enhanced crop variant that perhaps has 5% to 10% less yield than a standard variant but one that is substantially more nutritious? Such crops would be a benefit to human nutrition especially in populations at risk for iron and zinc deficiency, and a benefit to the sustainability of agricultural production. Full article

Biofortification of folates in staple crops is an important strategy to help eradicate human folate deficiencies. Folate biofortification using genetic engineering has shown great success in rice grain, tomato fruit, lettuce, and potato tuber. However, consumers’ skepticism, juridical hurdles, and lack of economic model have prevented the widespread adoption of nutritionally-enhanced genetically-engineered (GE) food crops. Meanwhile, little effort has been made to biofortify food crops with folate by breeding. Previously we reported >10-fold variation in folate content in potato genotypes. To facilitate breeding for enhanced folate content, we attempted to identify genes that control folate content in potato tuber. For this, we analyzed the expression of folate biosynthesis and salvage genes in low- and high-folate potato genotypes. First, RNA-Seq analysis showed that, amongst all folate biosynthesis and salvage genes analyzed, only one gene, which encodes γ-glutamyl hydrolase 1 (GGH1), was consistently expressed at higher levels in high- compared to low-folate segregants of a Solanum boliviense Dunal accession. Second, quantitative PCR showed that GGH1 transcript levels were higher in high- compared to low-folate segregants for seven out of eight pairs of folate segregants analyzed. These results suggest that GGH1 gene expression is an indicator of folate content in potato tubers. Full article