Soybean is the second most important agricultural commodity and the number one oil seed crop in the United States (US). It occupies more than 28% of the total acreage of crops planted in the US with an estimated value of over $18 billion. The global demand for food-grade soybean has increased significantly for human consumption, primarily due to health benefits and nutritional value of soybean and soybean products. Soybeans have inherent benefits in agricultural production (e.g., biological nitrogen fixation) and documented health benefits (e.g., the anticancer benefits of phytoestrogens). Our lab, as part of the National Center for Soybean Biotechnology, is using various tools of genomics and molecular breeding with an aim towards development of superior soybean varieties that will help US farmers maintain their competitiveness and expand utilization of soybean crops (e.g. functional foods, industrial uses, biodiesel, etc).
Some of our research efforts are highlighted below:
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| I. Metabolomics |
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In addition to being one of the richest sources of protein and oil, soybean seed is also one of the key sources of phytochemicals and has considerable potential as a source of several compounds and small molecules for human health. Another important factor is that various environmental stresses, such as drought and temperature, regulate the soybean metabolome. Thus metabolic fingerprinting during different developmental stages under stress conditions can lead to the discovery of chemical diversity.
With the focus on soybean seed composition, our overall goal is the identification of novel soybean metabolites for human health and nutrition which eventually contribute to improved soybean nutritional value using metabolic engineering. Specific objectives include: development of soybean metabolic fingerprinting technologies for the identification of potential compounds and small molecules for human health and nutrition, and the application of metabolite profiling to understand the alteration in the soybean metabolite composition due to natural variation and abiotic stress responses.
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| II. Functional Food Ingredients for Human Health: |
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Development of modified soybeans with dietary supplements will extend to a interdisciplinary research team having skills in human physiology, nutrition, and plant genomics to explore new vistas in nutritional genomics. Recent studies point out major bioactive compounds from soybeans including phytosterol, polyphenols, and small peptides are affected by the genotype and the planting location. Research is in progress to survey diverse soybean germplasm to obtain a comprehensive picture of the natural genetic variation in terms of the extent of accumulation of these molecules in soybean seeds. Identification of exotic germplasm will allow the introgression of genes regulating major functional food traits and bioactive compounds into adapted elite soybean cultivars. Streamlining of extraction and identification procedures for a high throughput breeding and selection of specific components will improve the rapid commercialization of varieties with high expression of desired components for food and pharmaceutical uses.
Recent developments in plant functional genomics and genetics helps us to select ideal tools including metabolomics to develop soybeans with higher amounts of dietary supplements or bioactive molecules. Our lab focuses on major functional food ingredients from soybeans including isoflavones, phytosterols, anthocyanins, and small peptides including the anticancer peptide soybean lunasin and the discovery of novel molecules with potential human health benefits. Â Collaborations with researchers from animal nutrition, animal physiology, and biochemistry, will allow us to test the effects of these bioactive compounds in animal and cell culture models. |
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| III. Genetic Manipulation of Seed Oil: |
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There is a wide range of genetic variation in protein and oil content among more than18,000 accessions of USDA soybean germplasm collections. The protein content among these collections varies between 34-56% with a median of approximately 42%, whereas oil content ranges from 8-27% with a median value of approximately 20%. In the United States (US), more than 13 billion pounds of soy oil is consumed in food-based products, whereas the industrial application of soy oil accounts for approximately 4% of the total soy oil consumption in the US. Given the flexibility of the world market for oil seed products, the development of soybean having superior oil traits (quantity and quality) has great promises to expand its competitiveness. The long term goal is to apply discoveries in breeding programs and biotechnology for the development of improved soybean cultivars with increased oil content that will make soybean more competitive in end-use applications.Â
Our multidisciplinary approaches include traditional Quantitative Trait Loci (QTL) mapping, association mapping, bioinformatics, and transgenics by developing new resources and utilizing already available resources such as mapping populations, diverse germplasm collections, genome sequence information, and transgenes. In addition to total oil content, we are focusing on improving quality traits such as oleic acid which has direct human health benefits and application in biodiesel production. The surplus oil from genetically modified soybean can be diverted towards biodiesel production or other industrial applications. In the genetic engineering element of this project, we are using Arabidopsis as an experimental tool to speed up the process of trait discovery. We are over-expressing different combinations of genes from heterologous sources in a seed specific manner to get the desired phenotype. Additionally efforts are also underway to explore the metabolic roles of some of the genes predicted to be associated with lipid/sterol metabolism in order to impart useful traits in soybean.
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