Most people believe they eat enough fiber, but research shows at least 9 out of 10 don’t. That means 90% of Americans are falling short on a key part of a diet that protects against a range of illnesses.
Fiber fuels the trillions of microorganisms in our guts, helping them flourish. In return, they support our digestion and immune system, and even our brain health.
For those of us who consume too much processed food in our diet, which are often low in fiber or lacking fiber entirely, meeting the daily recommended intake can be particularly challenging. However, an ongoing collaborative study involving researchers from Â鶹ӳ» may help bridge that gap.
The research, led by Steven Frese, an assistant professor in the Department of Nutrition at the University’s College of Agriculture, Biotechnology & Natural Resources, has identified three previously undocumented enzymes that separate complex carbohydrates from proteins, whether those proteins are from plant- or animal-derived sources. One example of these examples is whey or soy protein, commonly used to boost the protein content of processed foods and baked goods.
When incorporated into food processing, these enzymes, known as ENGases, could release those carbohydrates attached to dietary proteins. By releasing the sugars sooner, they can become more accessible for the gut microbiome as fiber and may enhance their effectiveness in supporting overall health.
The research team published their findings on April 8 in the journal "." The team consisted of researchers from the Â鶹ӳ» and Çanakkale Onsekiz Mart University in Turkey. Frese was the lead researcher, and his doctoral student Matt Bolino was the lead author.
“This project challenged my critical thinking and exposed me to new microbiology skills that I will carry into my next endeavor,” Bolino said. “Collaborating across labs opened the door to new partnerships that I hope continue, and working under Professor Frese’s mentorship was especially rewarding. His industry perspective and support helped me grow into a more independent scientist.”
Frese, who leads the , where Bolino conducts his research, brings about a decade of industry experience in developing dietary products. His lab’s latest findings contribute to an ongoing effort to improve the nutritional value of processed foods, an essential challenge for those struggling to meet fiber intake recommendations.
“A healthy diet can help manage many chronic conditions, such as diabetes, high cholesterol and high blood pressure, but for many people, trying to add in fiber-added processed foods can be expensive or unappealing,” said Frese, who also conducts research as part of the University’s . “For some people who struggle to get enough fiber-rich foods, I think it makes sense to try to make foods – especially the processed ones – healthier where we can, and that has been a big goal of our research.”
Identification, cloning and production of the novel enzymes
The researchers identified the enzymes as part of an ongoing survey of human fecal samples collected from adults in Â鶹ӳ». Participants provided diaries detailing their dietary intake, lifestyle habits and demographic backgrounds, and agreed to submit fecal samples.
The study's selection criteria were designed to yield fecal samples rich in gut bacterial variety, reflecting Â鶹ӳ»'s socioeconomic and demographic diversity. This approach also provided the researchers with the flexibility to perform exhaustive tests on the various gut microbiomes.
Using advanced DNA sequencing and shotgun metagenome sequencing, the researchers reconstructed the genes of the sampled gut bacterial communities, identifying and predicting their enzyme functions. After pinpointing potential sequences, they used Escherichia coli (E. coli) to produce the enzymes for more robust analyses, confirming the sequence and activity of the predicted enzymes. Further tests showed that the enzymes were able to release the complex carbohydrates found attached to glycoproteins.
With further research needed, the researchers will next study whether these released carbohydrates function effectively as fiber within diverse microbial environments, such as the gut. The goal is to demonstrate that these enzymes can indeed be used in food processing to help increase the bioavailability of fiber already found in our food.
"Rather than simply supplementing fiber, we’re exploring how to unlock fiber that is already present in food,” Frese said. “This research is just the beginning of understanding what’s possible in bridging the gap between dietary recommendations and real-world consumption patterns.”
Other members of the research team from the Â鶹ӳ» include nutrition master’s student Odunayo Abiodun, as well as Associate Professor Amilton de Mello and his doctoral student Nadini Haththotuwe Gamage in the Department of Agriculture, Veterinary & Rangeland Sciences. Members of the research team from Çanakkale Onsekiz Mart University in Çanakkale, Turkey, include Professor Sercan Karav and Hatice Duman in Molecular Biology and Genetics.
This research was supported by a New Investigator Seed Grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture (NIFA), the Â鶹ӳ» IdEA Network for Biomedical Research Excellence (INBRE), and the National Institute of General Medical Sciences (NIGMS) of the National Institutes of Health. Additional support came from the Â鶹ӳ»’s Department of Nutrition; College of Agriculture, Biotechnology & Natural Resources; Experimental Station; and Office of the Vice President for Research and Innovation.
