Functional crops are coming-A A +A
Sunday, May 4, 2014
COMING SOON: Food products that contain higher levels of phytosterols for reduced cholesterol, crops with higher levels of carotenoids for increased vitamin A, potato loaded with antioxidants, low-linolenic soybean, and high-lysine corn.
These may be farfetched but the possibilities are endless. Thanks to genetic engineering, the crops of the future will no longer be just dreams but realities. Already, the world has seen eggplant and corn that defy pests, vitamin A-rich rice, herbicide tolerant soybean, virus resistant papaya, and high laureate canola.
They are called genetically modified (GM) crops, which are products of biotechnology, a "technique that makes use of organism (or parts of it) to make or modify products, to improve plants or animals, or to develop microorganisms for specific purposes."
GM crops are made through a process called genetic engineering. Dr. Antonio Alfonso, a plant breeder at the Philippine Rice Research Institute (PhilRice) and the Crops Biotechnology Center director said genetic engineering is employed because of the following reasons: the trait is not present in the germplasm of the plant; the trait is very difficult to incorporate using conventional breeding methods; and it would take a very long time to introduce and/or improve such trait in the crop through conventional breeding.
In 1994, Calgene's delayed-ripening tomato became the first GM food crop to be produced and consumed in an industrialized country. Other GM crops -- corn, soybean, cotton, canola, and eggplant -- followed. These are called "first generation" crops which have proven their ability to lower farm-level production costs.
Now, research is focused on "second generation" GM crops that will feature increased nutritional and/or industrial traits. These crops will have more direct benefits to consumers. Examples include: potatoes with higher starch content and inulin; edible vaccines in corn, banana, and potatoes; corn varieties with low phytic acid and increased essential amino acids; healthier oils from soybean and canola; and allergen-free nuts.
These are called functional foods. It is defined as "foods or dietary components that claim to provide health benefits aside from basic nutrition." These foods contain biologically active substances such as antioxidants that may lower the risks from certain diseases associated with aging.
"Diet and health are closely related," explains the International Service for the Acquisition of Agri-biotech Applications (ISAAA). "Thus crops are now being enhanced through biotechnology to increase levels of important biologically active substances for improved nutrition, to increase body's resistance to illnesses, and to remove undesirable food components."
Linoleic acid (LA), alpha-linolenic acid (ALA), and polyunsaturated fatty acids (PUFAs) are some of the essential fatty acids. These are considered essential because they cannot be synthesized by the human body. A large number of scientific research studies suggest that higher dietary essential fatty acid intakes are associated with reductions in cardiovascular disease risk.
The main food sources of the long-chain Omega-3 fatty acids are fish. Plants lack the enzymes to make long-chain fatty acids needed by human beings. Scientists at the University of Bristol modified Arabidopsis thaliana to produce long-chain PUFAs.
"The transgenic plants were modified with three genes encoding different enzymes that convert linoleic and alpha-linoleic acids to the long-chain PUFAs," the ISAAA briefing paper said. "This experiment opened the possibility for the improvement of crops."
Antioxidants are important biological compounds that can protect the body by neutralizing the activity of the harmful free radicals, which are generated by pollution, radiation, cigarette smoke and herbicides.
Antioxidants come in different forms with phenolic compounds -- like flavonoids and tocopherols -- being in the most common. They are found in most fruits and vegetables such as cabbage, carrots, broccoli, aubergine, berries, and potatoes. They are plentiful in coffee, tea, and red wine.
To enhance the flavonoid content of potatoes, some scientists conducted single and multiple-gene transformations for the enzymes in the biosynthesis of flavonoids. The result of the study: GM plants exhibited significantly increased levels of phenolics and improved antioxidant capacity.
"Functional foods through biotechnology can provide developing countries food sources with increased nutritional value," the ISAAA briefing paper noted. "Staple starchy crops such as cassava and yams have been modified to lower the amylopectin content of starch, which has been associated with diet-related conditions such as type 2 diabetes.
"In areas of drought and poor soil quality, where high quality proteins are scarce, genetic modification has been undertaken on some legumes and in soybean to increase the levels of high proteins," the briefing paper added.
Despite all these, people are still worried about eating GM products. Are they safe to eat? Here's what the Geneva-based World Health Organization says: "The potential direct health effects of GM foods are generally comparable to the known risks associated with conventional foods, and include, for example, the potential of allergenicity and toxicity of components present, and the nutritional quality and microbiological safety of the food."
Published in the Sun.Star Davao newspaper on May 05, 2014.