Improving health through stevia research

Two Fort Valley State University researchers are investigating ways to remove the aftertaste

Jul. 16, 2019

Fort Valley State University scientists study ways small farmers can grow and sell stevia in the U.S.

D’Amber Jones, a biotechnology graduate student, assists Dr. Steven Samuels in the laboratory and field.

Two Fort Valley State University researchers are investigating ways to help local farmers grow a naturally sweet plant that could have a huge impact on human health.

“Stevia possesses anti-inflammatory properties and is an all-around health additive that we are going to use as a sweetener,” said FVSU research professional Dr. Steven Samuels. He is working with Dr. Bipul Biswas, assistant professor of plant science, who received a grant to study stevia for four years on FVSU’s campus.

“It is non-caloric, so it does not cause weight gain. It regulates insulin and glucose levels, which Americans have high incidents of that. We use a lot of sugar,” Samuels explained. “By having this as a product that we produce and promote, it will change the way people diet.”

For this reason, the FVSU graduate, who earned a bachelor’s degree in plant science-biotechnology, and Biswas plan to develop cultivars of stevia that can effectively grow in Georgia’s climate and soil. Furthermore, they are working on developing secondary glycosides (sweet tasting products) that do not have a bitter aftertaste.

Samuels explained that currently on the shelves in grocery stores, stevia products contain rebaudioside A, which is a secondary metabolite that is nearly 200 to 300 times sweeter than sugar.“It starts out sweet, but then at the end, it is a bit tangy. That is rebaudioside A. The plant naturally produces a high amount of it,” Samuels said.

The leaves also produce rebaudiosides D and M in very low quantities. “They are just as sweet but have none of the bitter aftertaste,” he said. The goal is to increase the production of D and M. “We believe we can do it because rebaudioside A is a precursor for D and M,” Samuels said.

To pull this scientific endeavor off, this will require Samuels and Biswas to breed those specific plants. First, they will plant several different lines in the field on campus and observe them as they grow. “We are collaborating with researchers from Michigan State University (MSU). They have the capability to quantify and identify each individual rebaudioside,” Samuels said. MSU will also do a genetic analysis to support their testing.

“When they identify other samples that fit the perimeters, we will breed those, plant the seeds and do the analysis again,” he added. “It’s a process of doing that until we identify lines phenotypically. The genetic information validates what we see and taste.”

The Thomson, Georgia, native said this project will benefit consumers and producers. The purpose is to develop a product that small farmers can grow and sell in the United States. To kick off the research process, Samuels said they have already started intercropping studies in the peach field on campus by growing stevia and strawberries underneath the peach trees.

“You are using the same amount of land and the same amount of time to increase your revenue,” Samuels said. “Once you plant stevia, it regrows the next season after harvesting.” He said this could especially benefit small farmers who may have multiple peach trees.

“Your peach leaves fall, decay and add nutrients to the soil for the stevia to grow. This increases overall farm profitability,” he advised.

In addition to growing stevia in the field, the Tuskegee University alumnus, who earned a doctorate in integrative biosciences through a joint program with the University of California, Davis, said they are looking at using hydroponics to promote sustainable agriculture.

“Less soil, less land, less water,” he noted. “Growing outside, you’re subject to the seasons, so you have a limited amount of time to generate profit. Growing hydroponically, you can grow all year round.”

Furthermore, Samuels said it is fulfilling to return to his alma mater as an employee and work on a project that allows him to work in both the laboratory and field.

“I enjoy being back here where I received my degree. It means a lot to me to be able to help others and impart the knowledge that I have gained,” he said, proudly.

FVSU biotechnology graduate student D’Amber Jones and five undergraduates are assisting Samuels and Biswas on the project. Their responsibilities range from cleaning and maintenance of the greenhouse, laboratories and fields to participating in germination experiments.

Biswas received $345,406 from a $3,208,657 grant awarded to MSU for his project, “Developing a sustainable stevia industry in the United States.” The U.S. Department of Agriculture’s (USDA) National Institute of Food and Agriculture (NIFA) is funding the project through its Specialty Crop Research Initiative (SCRI) program.

For more information, contact Samuels at (478) 825-3134 or steven.samuels@fvsu.edu, or Biswas at (478) 825-6827 or biswasb@fvsu.edu.